72 results on '"Li, Weiguang"'
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2. Topological arrangement of coronal segments in human callosal fibers in vivo tractography
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Zhang, Hui, Feng, Yuan, Li, Weiguang, Liang, Xili, Huang, Guanglong, and Qi, Songtao
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Cellular and Molecular Neuroscience ,Neuroscience (miscellaneous) ,Anatomy - Abstract
The topography of human callosal fibers in the midsagittal corpus callosum (mid-CC), in terms of cortical termination, is inconsistent in the literature. Despite being a high-profile and controversial topic, heterotopic callosal bundles (HeCBs) have not been studied from a whole-brain perspective. Here, we used multi-modal magnetic resonance imaging data from Human Connectome Project Development to explore these two topographic aspects by combining whole-brain tractography based on multi-shell multi-tissue constrained spherical deconvolution, the post-tractography reducing-false-positive-streamline algorithm of Convex Optimization Modeling for Microstructure Informed Tractography 2, and the new cortex parcellation atlas of Human Connectome Project multi-modal parcellation, version 1.0. We proposed that the callosal streamlines would demonstrate a topological arrangement of coronal segments arranged from anterior to posterior, with each perpendicular to the long axis of the mid-CC following its natural curvature, and the adjacent segments overlapping one another owing to the existence of HeCBs. We found that the cortices connected by the coronal segments, from anterior to posterior, corresponded exactly to the cortices from anterior to posterior in the flattened cortical surfaces of this atlas, indicating the original relative positions of the neocortex before curling and flipping during brain evolution. For each cortical area defined by this atlas, the sum strength of the HeCBs was far greater than that of the homotopic callosal bundle. Our findings on the topography of the whole CC would help in further understanding the network between the bilateral hemispheres and preventing disconnection syndromes in clinical settings.
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- 2023
3. Effect of Slag Gypsum Binder as a Substitute to Cement on the Stability of Backfill Mining
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Yang Xiaobing, Yan Zepeng, Li Weiguang, Wang Leiming, and Yin Shenghua
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Materials Science (miscellaneous) - Abstract
To effectively apply slag-gypsum binder (SGB) to most modern mines. An experimental study is conducted to investigate the feasibility and reliability of slag-gypsum binder (SGB) to replace cement in the mine backfill to effectively apply SGB in modern mines. The optimum parameters of aggregate and SGB fineness were investigated on a laboratory basis and the effect of concentration on the workability was analyzed. Also, industrial tests were carried out to study the cementitious properties of SGB and compared to cement. Finally, the hydration properties of SGB were analyzed using XRD and SEM. The results indicated that the main hydration products of SGB are C-S-H gel and ettringite, while Ca(OH)2 is consumed during the hydration process. In addition, the structure formed in the later stage of SGB is more compact. SGB is beneficial to the strength of the waste rock mixture. The sample prepared with the waste rock-rod milling sand-river sand mixture has a maximum strength of 7.54 MPa at 28 d. Reducing fineness is beneficial to form early strength. However, a specific surface area exceeding 510 m2/kg will harm the later strength. Surface area is less (400 m2/kg), the sample strength decreases when the dosage increases. Comparing the workability of SGB slurry and cement slurry, it is found that there is no essential difference between them under different mass concentration conditions. SGB slurry shows better fluidity and stability at a mass concentration of 80–82%. Industrial backfill experiments show the 3-, 7-, and 28-d strengths of SGB samples under 80% mass concentration conditions are 0.91 times, 1.43 times, and 1.2 times the cement samples. Therefore, using SGB instead of cement to backfill is a good application prospect.
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- 2022
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4. Design and implementation of intelligent traffic and big data mining system based on internet of things
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Li Weiguang, Shuyan Zhang, Yong Zhang, and Juan Zhu
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Statistics and Probability ,World Wide Web ,Artificial Intelligence ,business.industry ,Computer science ,General Engineering ,Internet of Things ,business ,Big data mining - Published
- 2020
5. Additional file 1 of Reactivity and kinetics of 1,3-butadiene under ultraviolet irradiation at 254 nm
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Liang, Min, Yu, Chang, Dai, Suyi, Cheng, Haijun, Li, Weiguang, Lai, Fang, Ma, Li, and Liu, Xiongmin
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Additional file 1: Figure S1. Total ion flow diagram of 1,3-butadiene thermal reaction products measured by GC-MS. Figure S2. Total ion flow diagram of 1,3-butadiene photolysis reaction products measured by GC-MS.
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- 2022
- Full Text
- View/download PDF
6. Combined administration of PTX and S-HM-3 in TPGS/Solutol micelle system for oncotarget therapy
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Li,Weiguang, Xue,Jianpeng, and Xu,Hanmei
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Male ,Paclitaxel ,TPGS ,Mice, Nude ,Solutol ,Antineoplastic Agents ,combination therapy ,Polyethylene Glycols ,anti-multidrug resistance ,Inhibitory Concentration 50 ,International Journal of Nanomedicine ,Cell Movement ,Cell Line, Tumor ,Neoplasms ,Animals ,Humans ,Vitamin E ,Tissue Distribution ,Whole Body Imaging ,Micelles ,Original Research ,Drug Carriers ,Mice, Inbred BALB C ,Cell Death ,Tumor Burden ,angiogenesis inhibitor ,Female ,Stearic Acids - Abstract
Weiguang Li, Jianpeng Xue, Hanmei Xu State Key Laboratory of Natural Medicines, The Engineering Research Center of Synthetic Polypeptide Drug Discovery and Evaluation of Jiangsu Province, Department of Marine Pharmacy, China Pharmaceutical University, Nanjing 211198, PR China Background: S-HM-3 is a tumor angiogenesis inhibitor with short half-life (25 min). In this present, TPGS/Solutol polymeric micelles was prepared to load together insoluble paclitaxel (PTX) and soluble S-HM-3, expecting to together deliver them to the tumor site with long-circulating, targeting function and combating multi-drug resistance (MDR). Materials and methods: PTX and S-HM-3 loaded TPGS/Solutol micelles (PHTSm) were prepared by the method of thin-film evaporation, and characterized by dynamic light scattering, transmission electron microscope (TEM), atomic force microscopy (AFM) and releasing properties. The anticancer effect of the polymeric micelles system was evaluated and confirmed by experiments of in vitro cell uptake study, in vivo pharmacokinetics, and pharmacodynamics studies. Results: Micelles exhibited smooth spherical morphology with 20~30 nm and low critical micelle concentration (CMC) value of 0.000124 mg/mL. Only about 30% of PTX were slowly released from micelles at 48h, which can beneficial to the long circulation in blood. The results of in vitro cell assay proved that S-HM-3 could be easier to get into MDA-MB-231 cell, and its angiogenesis inhibition ability was also enhanced after integrating into micelles. In particular, the results of in vivo studies showed that the half-life of S-HM-3 and PTX was significantly prolonged 25.27 and 5.54 folds, and their AUC0-∞ was enhanced 129.78 and 15.65 times, respectively. Meanwhile 83.05% tumor inhibition rate of PHTSm was achieved compared with 59.99% of PTX. Conclusions: TPGS and Solutol micelles hold promising potential to resolve the conundrum of combined therapy of cytotoxic drug and angiogenesis inhibitor with different physicochemical property and anticancer mechanism in clinical use. Keywords: paclitaxel, angiogenesis inhibitor, combination therapy, TPGS, Solutol, anti-multidrug resistance
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- 2019
7. Effective Removal of Tetracycline by Using Biochar Supported Fe3O4 as a UV-Fenton Catalyst
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Feng Wei, YU Xiaodan, Lin Xinchen, and LI Weiguang
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Scanning electron microscope ,Chemistry ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Catalysis ,law.invention ,law ,Transmission electron microscopy ,Biochar ,Degradation (geology) ,Calcination ,0210 nano-technology ,Electron paramagnetic resonance ,Powder diffraction ,Nuclear chemistry - Abstract
Novel Fe3O4-decorate hierarchical porous carbon skeleton derived from maize straw(Fe3O4@MSC) was synthesized by a facile co-precipitation process and a calcination process, which was developed as a UV assisted heterogeneous Fenton-like catalyst. The as-synthesized catalysts were characterized via X-ray powder diffraction(XRD), scanning electron microscope(SEM), transmission electron microscope(TEM), Brunauer-Emmet-Teller(BET) and vibrating sample magnetometer(VSM) at room temperature. The morphology and structure analysis revealed that the as-prepared Fe3O4@MSC retained the original pore morphology of the maize straw material. The non-uniform polyhedral Fe3O4 grew on the whole surface of the MSC, which reduced the aggragation of Fe3O4 and provided more active sites to strengthen the UV-assisted Fenton-like reaction. As a result, the tetracycline(TC) degradation efficiency after 40 min reaction and total organic carbon(TOC) removal efficiency after 2 h reaction of Fe3O4@MSC catalyzing UV-Fenton system reached 99.2% and 72.1%, respectively, which were more substantial than those of Fe3O4@MSC/H2O2(31.5% and 2%), UV/H2O2 system(68% and 23.4%) and UV/Fe3O4/H2O2(80% and 37.5%). The electron spin resonance(ESR) results showed that the •OH played an important role in the catalytic reaction. A possible degradation pathway of TC was proposed on the basis of the identified intermediates. Overall, the UV assisted heterogeneous Fenton-like process in Fe3O4@MSC improved the cycle of Fe3+/Fe2+ and activated the interfacial catalytic site, which eventually realized the enhancement of degradation and mineralization to tetracycline.
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- 2018
8. Target Tracking Algorithm Combining Improved GMS and Correlation Filtering
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Liu Qihong, Hao Wan, Xuehuan Ji, Dang Delin, Jiaxiang Dong, and Li Weiguang
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Robustness (computer science) ,Computer science ,Feature (computer vision) ,Frame (networking) ,Outlier ,RANSAC ,Tracking (particle physics) ,Grid ,Algorithm ,Blossom algorithm - Abstract
Aiming at the problem that traditional target tracking algorithms cannot detect and track specific targets in the real environment (such as airports) due to the given initial frame target position, this article proposes a target tracking algorithm that combines improved Grid-based Motion Statistics (GMS) matching algorithm and correlation filtering tracking algorithm. First of all, for the problem that GMS cannot adapt to the detection of specific targets in realistic monitoring environment, a template size expansion method is proposed to disperse the centrally gathered feature points and Random Sample Consensus (RANSAC) is introduced to remove outliers in the center of similar areas. Second, the initial template of the tracking algorithm is the target detected by the improved GMS method, and it is used to extract features to train the correlation filter to determine the target position of the video sequence. Finally, two groups of comparative experiments show that not only the improved GMS algorithm has better target detection performance, but also the fusion algorithm has better reliability and robustness for target tracking.
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- 2020
9. TRPV4 Overexpression Promotes Metastasis Through Epithelial–Mesenchymal Transition in Gastric Cancer and Correlates with Poor Prognosis
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Wang,Huafeng, Zhang,Benyan, Wang,Xue, Mao,Jianhua, Li,Weiguang, Sun,Yunwei, Yuan,Yaozong, Ben,Qiwen, Hua,Li, and Qian,Aihua
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OncoTargets and Therapy - Abstract
Huafeng Wang,1,* Benyan Zhang,1,* Xue Wang,1,* Jianhua Mao,2 Weiguang Li,3 Yunwei Sun,3 Yaozong Yuan,3 Qiwen Ben,3 Li Hua,4 Aihua Qian3 1Department of Pathology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 2State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 3Department of Gastroenterology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 4Faculty of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Aihua Qian; Li Hua Email qianaihua1981@126.com; seyhuali@163.comPurpose: Transient receptor potential vanilloid 4 (TRPV4) has been reported to be involved in the progression of several human tumors. Nevertheless, clinical significance and molecular mechanism of TRPV4 in gastric cancer (GC) remain poorly defined.Patients and Methods: Immunohistochemistry assays were used to investigate the correlation between the expression of TRPV4 and epithelial–mesenchymal transition (EMT) markers in human GC tissues. The correlations between TRPV4 expression and clinicopathological features and between TRPV4 expression and survival rates were also examined. TRPV4 knockdown was performed by using small interfering RNAs. In vitro, Cell Counting Kit-8 (CCK-8) assay, colony formation assay, and transwell assay were employed to further explore the biological functions of TRPV4, and Western blotting was used to evaluate the changes in the expression of TRPV4 protein and EMT-related proteins in HGC-27 and MGC-803 human GC cell lines.Results: TRPV4 expression was upregulated in GC tissues and cell lines. TRPV4 overexpression was associated with greater depth of tumor invasion, lymph node metastasis, higher TNM stage, poor overall survival, and worse disease-free survival. TRPV4 expression was inversely correlated with E-cadherin expression and positively correlated with vimentin expression. In vitro, knockdown of TRPV4 inhibited GC cell proliferation, colony formation, and invasion. Furthermore, the knockdown of TRPV4 modulated EMT by upregulating E-cadherin expression and downregulating the expression of N-cadherin and vimentin. In addition, the EMT-related transcription factor Snail was downregulated, whereas the expression levels of other transcription factors such as Slug and Twist did not change.Conclusion: TRPV4 was upregulated in human GC and the overexpression of TRPV4 could promote GC progression, partially through Snail-mediated EMT.Keywords: TRPV4, gastric cancer, epithelial–mesenchymal transition, metastasis, prognosis
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- 2020
10. Pedestrian Target Tracking Algorithm Based on Improved RANSAC and KCF
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Jiale Wu, Hongjie Lu, Li Weiguang, Hao Wan, and Jiaxiang Dong
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Kernel (image processing) ,Computer science ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,0202 electrical engineering, electronic engineering, information engineering ,020207 software engineering ,020201 artificial intelligence & image processing ,02 engineering and technology ,Pedestrian ,RANSAC ,Algorithm ,Classifier (UML) - Abstract
In order to track the specific pedestrian targets in public places, a universal pedestrian tracking algorithm based on improved RANSAC and KCF (Kernel Correlation Filter) was proposed. First, the improved RANSAC algorithm is used to match the SURF descriptor, the surveillance video of the target is automatically identified and the location of the target is marked. Second, the KCF classifier and the foreground-background model based on the color feature are trained respectively to obtain the target confidence map through feature fusion, which are used to predict the location of the next frame of the target. Third, the improved algorithm and the original KCF were tracked on several public data sets respectively, the results show that accuracy of the improved algorithm is higher than the original one. Finally, the target tracking experiments of different public places are carried out, and the versatility of the proposed algorithm are verified.
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- 2020
11. Fault Feature Extraction of Flexible Thin-walled Bearings Based on VMD and MOMEDA
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Xuezhi Zhao, Li Weiguang, Hongjie Lu, Jiale Wu, and Hao Wan
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Bearing (mechanical) ,Correlation coefficient ,020209 energy ,Noise reduction ,Feature extraction ,020206 networking & telecommunications ,02 engineering and technology ,Time–frequency analysis ,law.invention ,law ,0202 electrical engineering, electronic engineering, information engineering ,Kurtosis ,Entropy (information theory) ,Deconvolution ,Algorithm ,Mathematics - Abstract
Aiming at fault feature extraction of thin-walled flexible bearing, a fault diagnosis method based on Variational Mode Decomposition (VMD) and Multipoint Optimal Minimum Entropy Deconvolution Adjusted (MOMEDA) is proposed. Firstly, the number of VMD layers is determined according to the correlation coefficient, and the kurtosis of each intrinsic mode functions (IMF) is calculated. The IMF component with the largest kurtosis is selected as the best component according to the kurtosis maximum criterion. Then the multipoint kurtosis of the best component is calculated to determine the optimal fault period and the MOMEDA is carried out. Finally, do the envelope spectrum analysis. By analyzing the fault signals of the outer and inner rings of flexible thin-walled bearings, it shows that this method can extract the fault feature frequency of flexible thin-walled bearings accurately and effectively. At the same time, this method is compared with the method based on VMD and MED (Minimum Entropy Deconvolution), and the results show that the method proposed in this paper not only has a strong noise reduction effect, but also can extract the fault feature frequency more accurately.
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- 2020
12. Research on Path Planning Method of Factory Intelligent Vehicle Based on RRT and Artificial Potential Field Method
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Li Weiguang, Dang Delin, Ji Xuehuan, Li Guo-chen, Wu Jiale, and Wan Hao
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Computer Science::Robotics ,Mathematical optimization ,Smoothness ,Computer science ,Trafficability ,Path (graph theory) ,Potential field ,Factory (object-oriented programming) ,Point (geometry) ,Terrain ,Motion planning - Abstract
In order to solve the problems of long and tortuous path, poor smoothness and poor trafficability in traditional RRT, this paper proposes a path planning algorithm based on the combination of RRT and artificial potential field. The nodes in RRT path are regarded as dynamic target points. The dynamic target point is always in the target direction of the current path node.The principle of gravity and repulsion of the artificial potential field method is introduced to achieve the path Local planning. The fusion algorithm avoids the problem that the artificial potential field method is easy to fall into local minimum value in pathplanning and planning failure in complex terrain. The simulation results show that the path planning method combining RRT and artificial potential field method has shorter path distance, better smoothness and higher passing ability.
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- 2020
13. Fault Feature Extraction Method for Flexible Thin-Walled Bearings Based on MOMEDA-MCKD
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Hao Wan, Li Weiguang, Chen Ru, and Yan Song
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Bearing (mechanical) ,Computer science ,law ,Feature (computer vision) ,Noise reduction ,Feature extraction ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Deconvolution ,Envelope (mathematics) ,Fault (power engineering) ,Signal ,Algorithm ,law.invention - Abstract
Because of the difference between the flexible thin-walled bearing and the common rolling bearing, there is a background impact load, which makes the fault feature extraction difficult. To solve this problem, a fault feature extraction method of the flexible thin-walled bearing based on MOMEDA-MCKD is proposed. The original fault signal is filtered and de-noising by multi-point optimal minimum entropy deconvolution (MOMEDA), and then the deconvolution signal is further de-noising by maximum correlation kurtosis deconvolution (MCKD). Finally, the envelope analysis of the signal is carried out. Compared with the MCKD algorithm, The improved method proposed in this paper has good noise reduction effect in extracting the fault features of flexible thin-walled bearings. The extracted bearing fault feature frequency is better matched with the theoretical value, which proves the effectiveness and accuracy of the MOMEDA-MCKD algorithm in extracting the fault features of flexible thin-walled bearing.
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- 2020
14. The Fourth International Workshop on Chemical Science and Pharmaceutical Research (CSPR2017)
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Quanquan Liu, Qing Shi, Jianjun Wei, Yajing Shen, Chunbao Wang, Lihong Duan, Sun Tongyang, Zhengzhi Wu, Atsuo Takanishi, Massimiliano Zecca, Li Weiguang, and W.F. Shang
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Pharmacology ,medicine.medical_specialty ,Physical medicine and rehabilitation ,medicine.diagnostic_test ,Chemical science ,business.industry ,medicine ,Motor nerve ,Robot ,Neurological examination ,General Medicine ,Toxicology ,business - Abstract
This paper is closed access. This is an abstract from the Fourth International Workshop on Chemical Science and Pharmaceutical Research (CSPR2017), 17–20 October 2017, Guangzhou, China.
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- 2017
15. Development of a novel paediatric surgical assist robot for tissue manipulation in a narrow workspace
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Quanquan Liu, Bo Zhang, Zhang Xin, Sun Tongyang, Fujie Masakatsu, Lihong Duan, Zhengzhi Wu, Chunbao Wang, Chaoyang Shi, and Li Weiguang
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Universal joint ,0209 industrial biotechnology ,Engineering ,Inverse kinematics ,business.industry ,Mobile manipulator ,SCARA ,0206 medical engineering ,Arm solution ,Control engineering ,02 engineering and technology ,Workspace ,Kinematics ,020601 biomedical engineering ,Industrial and Manufacturing Engineering ,law.invention ,020901 industrial engineering & automation ,Control and Systems Engineering ,law ,Robot ,business ,Simulation - Abstract
Purpose Paediatric congenital esophageal atresia surgery typically requires delicate and dexterous operations in a narrow and confined workspace. This study aims to develop a novel robot assisted surgical system to address these challenges. Design/methodology/approach The proposed surgical robot consists of two symmetrical slave arms with nine degree of freedoms each. Each slave arm uses a rigid-dexterous configuration and consists of a coarse positioning manipulator and a distal fine operation manipulator. A small Selective Compliance Assembly Robot Arm (SCARA) mechanism was designed to form the main component of the coarse positioning unit, ensuring to endure large forces along the vertical direction and meet the operational demands. The fine positioning manipulator applied the novel design using flexible shafts and universal joints to achieve delicate operations while possessing a high rigidity. The corresponding kinematics has been derived and then was validated by a co-simulation that was performed based on the combined use of Adams and MATLAB with considering the real robot mass information. Experimental evaluations for the tip positioning accuracy and the ring transfer tasks have been performed. Findings The simulation was performed to verify the correctness of the derived inverse kinematics and demonstrated the robot’s flexibility. The experimental results illustrated that the end-effector can achieve a positioning accuracy within 1.5 mm in a confined 30 × 30 × 30 mm workspace. The ring transfer task demonstrated that the surgical robot is capable of providing a solution for dexterous tissue intervention in a narrow workspace for paediatric surgery. Originality/value A novel and compact surgical assist robot is developed to support delicate operations by using the dexterous slave arm. The slave arm consists of a SCARA mechanism to avoid experiencing overload in the vertical direction and a tool manipulator driven by flexible shafts and universal joints to provide high dexterity for operating in a narrow workspace.
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- 2017
16. Inertial Sensor-Based Motion Analysis of Lower Limbs for Rehabilitation Treatments
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Quanquan Liu, Qihong Liu, Wanfeng Shang, Zhengzhi Wu, Meng Li, Chunbao Wang, Yulong Wang, Sun Tongyang, Lihong Duan, Li Hua, and Li Weiguang
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Engineering ,Motion analysis ,lcsh:Medical technology ,Inertial frame of reference ,Article Subject ,0206 medical engineering ,Biomedical Engineering ,Hemiplegia ,Health Informatics ,02 engineering and technology ,Motion (physics) ,03 medical and health sciences ,0302 clinical medicine ,Gait (human) ,Inertial measurement unit ,Humans ,Computer vision ,Range of Motion, Articular ,Gait ,Simulation ,lcsh:R5-920 ,business.industry ,Stroke Rehabilitation ,Motion detection ,020601 biomedical engineering ,Biomechanical Phenomena ,Lower Extremity ,lcsh:R855-855.5 ,Surgery ,Artificial intelligence ,lcsh:Medicine (General) ,business ,Range of motion ,Wireless Technology ,Rotation (mathematics) ,030217 neurology & neurosurgery ,Research Article ,Biotechnology - Abstract
The hemiplegic rehabilitation state diagnosing performed by therapists can be biased due to their subjective experience, which may deteriorate the rehabilitation effect. In order to improve this situation, a quantitative evaluation is proposed. Though many motion analysis systems are available, they are too complicated for practical application by therapists. In this paper, a method for detecting the motion of human lower limbs including all degrees of freedom (DOFs) via the inertial sensors is proposed, which permits analyzing the patient’s motion ability. This method is applicable to arbitrary walking directions and tracks of persons under study, and its results are unbiased, as compared to therapist qualitative estimations. Using the simplified mathematical model of a human body, the rotation angles for each lower limb joint are calculated from the input signals acquired by the inertial sensors. Finally, the rotation angle versus joint displacement curves are constructed, and the estimated values of joint motion angle and motion ability are obtained. The experimental verification of the proposed motion detection and analysis method was performed, which proved that it can efficiently detect the differences between motion behaviors of disabled and healthy persons and provide a reliable quantitative evaluation of the rehabilitation state.
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- 2017
17. Development of a New Variable Curvature Flexible Joint Based Surgical Manipulator for a Narrow Workspace
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Zhengzhi Wu, Li Weiping, Xingguang Duan, Haidong Wang, Zhang Xin, Li Weiguang, Jiaxiang Dong, Bo Zhang, Shang Wanfeng, Quanquan Liu, Masakatsu G. Fujie, Lihong Duan, and Wang Chunbao
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0209 industrial biotechnology ,Computer science ,Interface (computing) ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,0211 other engineering and technologies ,Base (geometry) ,Mechanical engineering ,02 engineering and technology ,Bending ,Workspace ,Kinematics ,Robot end effector ,Curvature ,GeneralLiterature_MISCELLANEOUS ,law.invention ,020901 industrial engineering & automation ,law ,Robot ,ComputingMethodologies_COMPUTERGRAPHICS ,021106 design practice & management - Abstract
Minimally invasive surgical space, especially narrow workspace such as throat and oral cavity, require much higher manipulative dexterity. The existing robotic surgical robots still suffer from the inflexible end effector, the coarse robot volume. In this paper, we propose a new minimally invasive surgical manipulator. It consists of a flexible joint and a fast connect interface. The flexible joint, comprised of an elastic machined spring and a rigid base rod, can achieve Omni-orientational bending movement with a variable curvature through adjusting the coupling length between the elastic machined spring and the rigid base rod. The fast connect interface, enabling a quick connection between the surgical manipulator and the drive house, can improve the operative efficiency on surgery. Kinematics and workspace of the flexible joint is presented, and the preliminary experiments demonstrate the bending reachability of the surgical manipulator under different bending curvature to adapt for narrow workspace.
- Published
- 2019
18. Solutol®HS15+pluronicF127 and Solutol®HS15+pluronicL61 mixed micelle systems for oral delivery of genistein
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Ding,Pinggang, Chen,Yuxuan, Cao,Guangshang, Shen,Hongxue, Ju,Jianming, and Li,Weiguang
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Drug Design, Development and Therapy - Abstract
Pinggang Ding,1,2,* Yuxuan Chen,3,* Guangshang Cao,4 Hongxue Shen,1,2 Jianming Ju,1,2 Weiguang Li,51Department of Pharmaceutical Analysis and Metabolomics, Hospital of Integrated Traditional Chinese and Western Medicine Affiliated to Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China; 2Department of Pharmaceutical Analysis and Metabolomics, Jiangsu Province Academy of Traditional Chinese Medicine, Nanjing, People’s Republic of China; 3School of Holistic Integrative Medicine, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China; 4Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, People’s Republic of China; 5Department of Marine Pharmacy, China Pharmaceutical University, Nanjing, People’s Republic of China*These authors contributed equally to this work Purpose: We aimed to prepare two oral drug delivery systems consisting of polyoxyl 15 hydroxystearate (HS15) with pluronicF127 (F127) and HS15 with pluronicL61 (L61) to overcome the challenges of genistein’s poor oral bioavailability. This provides a good strategy for enhancing the potential value of genistein.Methods: We designed two binary mixed micelle systems employing the organic solvent evaporation method using surfactants (HS15, L61, and F127). Formulations (GEN-F and GEN-L) were characterized by transmission electron microscopy. Drug content analysis, including entrapment efficiency (EE%), drug loading (DL%), and the cumulative amount of genistein released from the micelles, was performed using HPLC. The permeability of optimum formulation was measured in Caco-2 cell monolayers, and the oral bioavailability was evaluated in SD rats.Results: The solutions of GEN-F and GEN-L were observed to be transparent and colorless. GEN-F had a lower EE% of 80.79±0.55% and a DL% of 1.69±0.24% compared to GEN-L, which had an EE% 83.40±1.36% and a DL% 2.26±0.18%. TEM results showed that the morphology of GEN-F and GEN-L was homogeneous and resembled a spherical shape. The dilution and storage conditions had no significant effect on particle size and EE%. Genistein demonstrated a sustained release behavior when encapsulated in micelles. Pharmacokinetics study showed that the relative oral bioavailability of GEN-F and GEN-L increased by 2.23 and 3.46 fold while also enhancing the permeability of genistein across a Caco-2 cell monolayer compared to that of raw genistein.Conclusion: GEN-F and GEN-L as a drug delivery system provide an effective strategy for enhancing and further realizing the potential value of GEN.Keywords: genistein, micelles, polyoxyl 15 hydroxystearate, pluronicF127, pluronicL61, oral bioavailability
- Published
- 2019
19. Feature frequency extraction algorithm based on matching pursuit and its application in axis orbit
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Zhen Li, Huang Jian, Cai Wenwei, Xinxin Zhang, and Li Weiguang
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lcsh:GE1-350 ,Rotor (electric) ,Computer science ,020206 networking & telecommunications ,02 engineering and technology ,Sparse approximation ,Matching pursuit ,Signal ,Displacement (vector) ,law.invention ,Feature (computer vision) ,law ,0202 electrical engineering, electronic engineering, information engineering ,Orbit (dynamics) ,020201 artificial intelligence & image processing ,Algorithm ,lcsh:Environmental sciences ,Energy (signal processing) - Abstract
Rotor displacement signal is an important state characteristic parameter of rotating machinery, which contains abundant operation information of rotating machinery. Aiming at the problem of purifying axis orbit in large -scale rotor test-bed, a new method of extracting the characteristic frequency and synthesizing axis orbit is proposed based on the matching pursuit algorithm (MP). In this paper, the sparse decomposition of signals in the algorithm is implemented by MP algorithm. The algorithm can accurately extract single or multiple feature frequencies. The purified curve is clearer and more efficient. Fault types can be found by extracting different characteristic frequency synthetic axis trajectories, so as to understand the operation status of the large-scale rotor test-bed.
- Published
- 2021
20. Fault characteristic frequency analysis of elliptically shaped bearing
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Li Weiguang, Guo Yingying, Wen-Bin Shangguan, Xuezhi Zhao, Hui Lü, and Chunliang Zhang
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Physics ,Frequency analysis ,Bearing (mechanical) ,Applied Mathematics ,020208 electrical & electronic engineering ,010401 analytical chemistry ,Mathematical analysis ,Fast Fourier transform ,02 engineering and technology ,Kinematics ,Condensed Matter Physics ,Fault (power engineering) ,01 natural sciences ,0104 chemical sciences ,law.invention ,Morlet wavelet ,law ,Feature (computer vision) ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,Instrumentation ,Excitation - Abstract
Elliptically shaped bearing (ESB) with complicated kinematics characteristic is easily damaged, there is not a theoretical formula for ESB fault characteristic frequency (FCF) due to its geometrical structure. A theoretical calculation method for ESB FCF based on analysis of the relationship between geometry and kinematics characteristics is proposed. The identification accuracy of fault type can be improved. The continuous Morlet wavelet transform (CMWT) combined with FFT-based Hilbert (FH) analysis (i.e., CMWT-FH) is utilized to extract the fault feature by suppressing the dominant rotational excitation of ESB against the FH method. Experiments are performed to verify the effectiveness of the proposed method. The experimental FCFs identified from the CMWT-FH spectrums of ESB signals are evidently close to the theoretical values calculated by using geometry and kinematics parameters of ESB (the errors are within 2%). The theoretical calculation method for ESB FCF has practical reference for the accurate detection in fault diagnosis.
- Published
- 2020
21. Amplitude filtering characteristics of singular value decomposition and its application to fault diagnosis of rotating machinery
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Li Weiguang, Tang Yalian, Xuezhi Zhao, Guo Mingjun, and Yang Qijiang
- Subjects
Bearing (mechanical) ,Rotor (electric) ,Applied Mathematics ,Feature extraction ,Mathematical analysis ,Condensed Matter Physics ,Fault (power engineering) ,Signal ,law.invention ,Singular value ,Amplitude ,law ,Singular value decomposition ,Electrical and Electronic Engineering ,Instrumentation ,Mathematics - Abstract
In this paper, two important properties of singular value decomposition (SVD) are deduced theoretically: (1) number law of singular values: one frequency corresponds to two singular values; (2) order rule of singular values: the larger the amplitude of signal is, the greater the corresponding two singular values are. The above two properties are collectively referred as amplitude filtering characteristics of SVD, and a signal separation algorithm (SVD-AF) based on this characteristic is proposed. Research shows that the algorithm shows excellent characteristics in both extracting multiple and single frequency components. What’s more, the purified signal does not contain redundant components, nor does phase deviation occur. Finally, the proposed algorithm is used to purify axis orbits of the rotor of large sliding bearing test bed, the obtained axis trajectories are clear and concentrated, and the misalignment as well as rub impact fault of the rotor is identified successfully.
- Published
- 2020
22. Design of 6-DOF Parallel Ankle Rehabilitation Robot
- Author
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Chen Xiaojiao, Wanfeng Shang, Yajing Shen, Jian Huang, Chunbao Wang, Lin Zhuohua, Lu Zhixiang, Xia Jinfeng, Suntong Yang, Li Weiguang, Zhengzhi Wu, Lihong Duan, and Quanquan Liu
- Subjects
musculoskeletal diseases ,medicine.medical_specialty ,Rehabilitation ,Computer science ,medicine.medical_treatment ,Rehabilitation evaluation ,Rehabilitation robot ,medicine.anatomical_structure ,Physical medicine and rehabilitation ,Ankle rehabilitation ,Rehabilitation training ,medicine ,Robot ,Ankle ,Rehabilitation robotics - Abstract
Hemiplegia caused by stroke usually requires a lot of rehabilitation to restore normal motor function. The ankle joint is an important structure for human walking, and its rehabilitation training is the basis for restoring the normal physiological functions of patients with hemiplegia. Compared with traditional manual rehabilitation training led by therapists, the rehabilitation robot can not only complete the repeated training process, but also accurately record the patient’s physiological data and make rehabilitation evaluation. Based on the parallel mechanism with simple structure and precise control characteristics, this paper establishes a prototype model of the ankle joint rehabilitation robot, simulates the ankle joint motion, and realizes the expected function.
- Published
- 2018
23. Robust Spatio-temporal Context Tracking Algorithm Based on Correlation Filter
- Author
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Quanquan Liu, Junkuan Cui, Lihong Duan, Chunbao Wang, Li Weiguang, and Wan Hao
- Subjects
Confidence map ,Computer science ,Motion blur ,Correlation filter ,Temporal context ,020207 software engineering ,02 engineering and technology ,Robustness (computer science) ,Spatial model ,Scale variation ,0202 electrical engineering, electronic engineering, information engineering ,Eye tracking ,020201 artificial intelligence & image processing ,Algorithm - Abstract
Spatio-temporal context (STC) algorithm transforms the tracking process into a series of processes to find the extremum of the confidence map and fully uses the density context information around the target, which makes the algorithm rapidity and robustness. However, STC cannot deal with the situation of scale variation, motion blur and occlusion, which will cause the spatial model update error and result in the failure of the algorithm to accurately extract the target area. To deal with the problem, an improved spatio-temporal context algorithm is proposed in this paper. Firstly, the target sidelobe ratio (PSR) is used to determine the occlusion of the target. The lower the PSR value is, the more serious the target is blocked. PSR can be obtained by analyzing the response map of the target area. Secondly, the scale correlation filter is used to improve the STC algorithm, so that the algorithm can accurately and completely extract the target area. Thirdly, in order to avoid contamination of the target template when the target is occluded, a template update strategy is introduced to adapt to the appearance change of the target. The template update strategy enables our algorithm to locate the target quickly when the occlusion disappearing. Finally, experiment results on public data set are provided to show the effectiveness and robustness of our proposed algorithm.
- Published
- 2018
24. Adaptive Control Strategy for Gait Rehabilitation Robot to Assist-When-Needed
- Author
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Quanquan Liu, Gong Chen, Jing Ye, Zhengzhi Wu, Li Weiguang, Chunbao Wang, and Lihong Duan
- Subjects
0209 industrial biotechnology ,Adaptive control ,Computer science ,0206 medical engineering ,02 engineering and technology ,Rehabilitation robot ,020601 biomedical engineering ,020901 industrial engineering & automation ,Gait (human) ,Inertial measurement unit ,Trajectory ,Robot ,Hidden Markov model ,Rehabilitation robotics ,human activities ,Simulation - Abstract
Conventional assist-as-needed (AAN) control strategies utilize only the deviation of user's limb to a predefined trajectory, but individual condition is not considered. In this paper, the control strategy of assist-when-needed (AWN) is proposed for gait rehabilitation robotics. The robot only provides assistance in any one of the seven gait phases involving the lower-limb impairments but it works in zero force mode in the other phases during walking. A synchronous reference trajectory is generated based on the gait phases. The gait phases are detected with IMU sensors and a hidden Markov model (HMM). The level of assistance is decided independently with the deviations in the seven gait phases. Then the adaptive robotic assistance is given to assist the human walking only when needed. This control strategy has been implemented in an exoskeleton robot and tested on one healthy subject. Experiment results showed that with this control strategy, the robot significantly increased knee joint angle ranges with the existence of external resistance. The experiment results revealed that the proposed control strategy is feasible and effective in delivering flexible assistance to the subjects during overground walking.
- Published
- 2018
25. Weibull Parameter Estimation Algorithm Based on Ant Colony
- Author
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Gong Chen, Wanfeng Shang, Zhen Li, Li Weiguang, Chunbao Wang, Cong Ye, Quanquan Liu, Zhuohua Lin, and Jing Ye
- Subjects
Maximum likelihood ,Ant colony optimization algorithms ,05 social sciences ,02 engineering and technology ,Ant colony ,Running time ,Parameter estimation algorithm ,Distribution (mathematics) ,020204 information systems ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,Method of steepest descent ,Statistics::Methodology ,Applied mathematics ,050211 marketing ,Weibull distribution ,Mathematics - Abstract
The Weibull distribution has high fitting accuracy and applicability to the life distribution of rolling bearings. Based on the assumption that life of rolling bearings obeys the Weibull distribution, the Weibull distribution parameters are estimated by using least-squares method (LSM), steepest descent method (SDA) and maximum likelihood estimation (M-L), meanwhile, the ant colony algorithm (ACO) is introduced to determine 2 parameters in Weibull distribution. The comparison and analysis of the fitting accuracy and operational efficiency of 4 kinds of algorithms under the index of fitness and running time are given. The results show that the applicability of ACO algorithm in estimating extremum parameters is proved.
- Published
- 2018
26. Vulnerabilities in UMTS Location Update Procedure and Its Countermeasures
- Author
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Li Weiguang, Zengshan Tian, and Yujia Yao
- Subjects
Computer science ,business.industry ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,020206 networking & telecommunications ,Denial-of-service attack ,02 engineering and technology ,Mutual authentication ,Universal Mobile Telecommunications System ,Base station ,GSM ,0202 electrical engineering, electronic engineering, information engineering ,ComputerSystemsOrganization_SPECIAL-PURPOSEANDAPPLICATION-BASEDSYSTEMS ,020201 artificial intelligence & image processing ,business ,UMTS frequency bands ,Computer network - Abstract
Mobile communication systems have been developing for decades. Universal Mobile Telecommunications System (UMTS) is a third-generation mobile cellular system for networks based on the GSM standard. As an evolved technology of GSM, UMTS has adopted a more reliable security mechanism. Integrity protection and mutual authentication were added in UMTS. However we carefully analyzed UMTS location update procedure specifications and uncover several vulnerabilities in UMTS. By sending specific types of LOCATION UPDATING REJECT messages during location update procedure, the rogue base station can deny all services to a target UMTS device. We also present several countermeasures including increasing the rate of TMSI reallocation, rebooting or re-inserting the SIM/USIM card and installing the protection application on UE to resist these vulnerabilities.
- Published
- 2018
27. Robust Visual Tracker via Cascade Classifying
- Author
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Li Weiguang, Xing Lin, Hao Wan, Guoqiang Ye, and Huidong Lou
- Subjects
0209 industrial biotechnology ,genetic structures ,Computer science ,business.industry ,Cognitive neuroscience of visual object recognition ,02 engineering and technology ,Visualization ,Statistical classification ,020901 industrial engineering & automation ,Robustness (computer science) ,Video tracking ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,Particle filter ,business ,Cascading classifiers - Abstract
Since the similar background interference and target occlusion, the result of many visual trackers occurred deviation and even lost the target. In this paper, we proposed a robust visual tracker combing with the results of object tracking and target identification to make our algorithm more robust. To do this, we use the cascade classifier to improve the performance of target identification algorithm, then adjust the consequence of object tracking algorithm which based on particle filter. Experiment results show that our method tracks target fast and robustly, and outperform the state-of-the-art tracking methods.
- Published
- 2018
28. An improved spatio-temporal context tracking algorithm
- Author
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Hao Wan, Guoqiang Ye, and Li Weiguang
- Subjects
Context model ,Computer science ,Robustness (computer science) ,010401 analytical chemistry ,Motion blur ,0202 electrical engineering, electronic engineering, information engineering ,Temporal context ,020201 artificial intelligence & image processing ,02 engineering and technology ,01 natural sciences ,Algorithm ,Motion vector ,0104 chemical sciences - Abstract
Spatio-temporal context (STC) algorithm transforms the tracking process into a series of processes to find the extremum of the confidence map and fully uses the density context information around the target, which makes the algorithm rapidity and robustness. However, STC cannot deal with fast motion, motion blur and the rapid change of scale, which will cause the spatial model update error and result in the failure of the algorithm to accurately extract the target area. To deal with the problem, an improved spatio-temporal context algorithm is proposed in this paper. Firstly, the position prediction based on the target motion vector is introduced, the motion information of the target is fully taken into account to improve the accuracy of the STC algorithm in extracting the target current position. Secondly, the scale correlation filter is used to improve the STC algorithm, so that the algorithm can accurately and completely extract the target area. Finally, experiment results on public data set are provided to show the effectiveness and robustness of our proposed algorithm.
- Published
- 2018
29. A numerical simulation on multi-spot pressure tensioning process of circular saw blade
- Author
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Xiaorui Peng, Li Bo, Zhankuan Zhang, and Li Weiguang
- Subjects
Biomaterials ,Stress (mechanics) ,Stress field ,Engineering ,Computer simulation ,Blade (geometry) ,business.industry ,Tension (physics) ,Process (computing) ,Structural engineering ,business ,Finite element method ,Circular saw - Abstract
The multi-spot pressure tensioning process of circular saw blade was built by dynamic/explicit solution module of the finite element software called ABAQUS for avoiding non-convergence and improving the computational efficiency. The stress field of circular saw blade during loading process was calculated based on the finite element model. The model which could both meet the requirement of computational efficiency and accuracy was established by adjusting the step time and density of circular saw blade. The unloading process of circular saw blade was built by static/general solution module of ABAQUS using the stress field of loading process calculated by dynamic/explicit finite element method as initial conditions. The tangential tensioning stress field of circular saw blade tensioned by multi-spot pressure which showed the same trend with the measured result was calculated based on the two above-mentioned models. A more ideal distribution of tangential tensioning stress could be produced by the multi-spot pressure tensioning process. The feasibility of multi-spot pressure tensioning process was theoretically proved in this paper.
- Published
- 2015
30. Effect of Yield Strength of a Circular Saw Blade on the Multi-spot Pressure Tensioning Process
- Author
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Li Bo, Li Weiguang, Zhankuan Zhang, and Xiaorui Peng
- Subjects
Engineering ,Finite element method ,Environmental Engineering ,Blade (geometry) ,business.industry ,lcsh:Biotechnology ,Process (computing) ,High strength steel ,Bioengineering ,Structural engineering ,Stress distribution ,Circular saw blade ,Stress (mechanics) ,Multi-spot pressure tensioning ,lcsh:TP248.13-248.65 ,business ,Waste Management and Disposal ,Circular saw ,High-strength steel - Abstract
In this study, a numerical model of the tangential tensioning stress distribution of a circular saw blade tensioned by multi-spot pressure was established using theoretical analysis, and the tangential tensioning stress distribution of the circular saw blade calculated by the model was shown to be true and reliable. The effect of yield strength of the circular saw blade on the distribution of tangential tensioning stress was studied using the numerical model. The research achievements showed that a circular saw blade made with high-strength or ultra-high-strength steel yielded a better tensioning effect during the multi-spot pressure tensioning process, which could promote the application of a circular saw blade made by high-strength or ultra-high-strength steel.
- Published
- 2015
31. Model for Tangential Tensioning Stress in the Edge of Circular Saw Blades Tensioned by Multi-Spot Pressure
- Author
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Li Weiguang, Zhankuan Zhang, Li Bo, and Xiaorui Peng
- Subjects
Engineering ,Finite element method ,Environmental Engineering ,Blade (geometry) ,business.industry ,lcsh:Biotechnology ,Mechanical Processes ,Bioengineering ,Structural engineering ,Edge (geometry) ,Circular saw blade ,Stress (mechanics) ,Physics::Fluid Dynamics ,Superposition principle ,Compressive strength ,Multi-spot pressure tensioning ,lcsh:TP248.13-248.65 ,business ,Waste Management and Disposal ,Circular saw - Abstract
In this study, a mathematical model of tangential tensioning stress in the edge of a circular saw blade tensioned by multi-spot pressure was established by theoretical analysis for the quality control of circular saw blades. The multi-spot pressure tensioning process was assumed to include three mechanical processes: the one-spot pressure process; the process of elastic deformation of a disk with a through-hole subjected to uniform, radial compressive stress; and the stress superposition process. The tangential tensioning stress on the edge of the circular saw blade could be accurately predicted by the established mathematical model. The model for the tangential tensioning stress on the edge of the circular saw blade tensioned by multi-spot pressure was shown to be correct by measured values.
- Published
- 2015
32. Feature Selection Tracking Algorithm Based on Sparse Representation
- Author
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Qinghe Yao, Guoqiang Ye, Huidong Lou, Hao Wan, Yueen Hou, and Li Weiguang
- Subjects
Article Subject ,business.industry ,lcsh:Mathematics ,General Mathematics ,Computation ,General Engineering ,Pattern recognition ,Feature selection ,Sparse approximation ,lcsh:QA1-939 ,Fast algorithm ,lcsh:TA1-2040 ,Robustness (computer science) ,Sample Label ,Eye tracking ,Artificial intelligence ,lcsh:Engineering (General). Civil engineering (General) ,business ,Algorithm ,Mathematics - Abstract
In order to enhance the robustness of visual tracking algorithm in complex environment, a novel visual tracking algorithm based on multifeature selection and sparse representation is proposed. In the framework of particles filter, particles with low target similarity are first filtered out by a fast algorithm; then, based on the principle of sparsely reconstructing the sample label, the features with high differentiation against the background are involved in the computation so as to reduce the disturbance of occlusions and noises. Finally, candidate targets are linearly reconstructed via sparse representation and the sparse equation is solved by using APG method to obtain the state of the target. Four comparative experiments demonstrate that the proposed algorithm in this paper has effectively improved the robustness of the target tracking algorithm.
- Published
- 2015
33. Kinematics analysis and motion planning of a redundant robotic manipulator for surgical intervention
- Author
-
Quanquan Liu, Li Weiping, Sun Tongyang, Wanfeng Shang, Bo Zhang, Li Weiguang, Masakatsu G. Fujie, Chunbao Wang, Yulong Wang, Xiaorui Li, Yajing Shen, Zhang Xin, Zhengzhi Wu, Lihong Duan, and Lin Zhuohua
- Subjects
Correctness ,Inverse kinematics ,Computer science ,business.industry ,Computation ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Kinematics ,Workspace ,Robot ,Shape optimization ,Computer vision ,Motion planning ,Artificial intelligence ,business ,ComputingMethodologies_COMPUTERGRAPHICS - Abstract
Robotic assisted technologies benefit surgeon for less workload via dexterous manipulation in minimally invasive surgeries (MIS). Redundant manipulator can provide sufficient dexterity and is potential to use in a confined and narrow workspace. We had designed a master-slave paediatric surgical assist robot, which consists of two symmetric slave arms with nine DOFs each for dexterous manipulation. This paper presents the kinematics computation of the redundant manipulator based on its geometrical structure, and then, a shape optimization algorithm is constructed to calculate the posture configuration along the redundant manipulator, subsequently, a collision avoidance algorithm is constructed to perform motion planning in a narrow workspace. The experiments were executed to validate the correctness of the derived inverse kinematics algorithm and the results demonstrated that the redundant manipulator is capable of performing dexterous manipulation with a positioning accuracy within 1.5 mm in a narrow surgical workspace.
- Published
- 2017
34. Development of a mobile APP for the operation monitoring and health management system of a steam turbine
- Author
-
Zhengzhi Wu, Sun Tongyang, Li Weiguang, Quanquan Liu, Chuan Chen, Yajing Shen, Qihong Liu, Qing Shi, Lihong Duan, Wanfeng Shang, and Chunbao Wang
- Subjects
Artificial neural network ,Computer science ,business.industry ,food and beverages ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Fault (power engineering) ,complex mixtures ,GeneralLiterature_MISCELLANEOUS ,Reliability engineering ,Wavelet packet decomposition ,Software ,Terminal (electronics) ,Steam turbine ,Mobile telephony ,State (computer science) ,business ,human activities - Abstract
In order to realize the real-time monitoring of the operation state and predict the possible faults of a steam turbine, a mobile APP based on the steam turbine operation monitoring and health management system is proposed in this paper. Firstly, some common faults which will be encountered in the operation of steam turbine are analyzed and the mechanism and characteristics of the faults are studied. Secondly, the hardware and software platform on the PC are built to diagnose the fault and analyze the trend by combining the methods of wavelet packet decomposition and BP neural network. Finally, the APP on the mobile terminal for the real-time operation monitoring of the steam turbine is developed. Furthermore, the test results of the mobile APP demonstrate that the developed mobile APP can effectively diagnose the fault and predict the trend. It also proved that the developed mobile APP can make the operation monitoring and health management system of the steam turbine run stably and meet the practical application requirements.
- Published
- 2017
35. New results in visual invariant features for improved image based visual servoing
- Author
-
Li Weiguang, Guoqiang Ye, and Hao Wan
- Subjects
Unit sphere ,0209 industrial biotechnology ,business.industry ,02 engineering and technology ,Kinematics ,Visual servoing ,Visualization ,03 medical and health sciences ,symbols.namesake ,Inner product space ,020901 industrial engineering & automation ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Jacobian matrix and determinant ,symbols ,Computer vision ,Artificial intelligence ,Invariant (mathematics) ,business ,Image based ,Mathematics - Abstract
Features selection plays an important role in image based visual servoing, the objective is to determine six independent visual features with nice decoupled and linear properties. Visual invariant is well-known as an ideal kind of features to design an improved IBVS. In this paper, a kind of visual invariant to rotational motions is derived from projection onto surface of a unit sphere, and it is calculated by vector inner product operation. Invariant based feature jacobian can be provided through a simple deduction with operation laws of vector or matrix. Then, six independent visual features are determined with three inner product features and homography-based features, and a decoupled IBVS controller is proposed. Finally, simulations results with a free-flying perspective camera are provided to illustrate the significance of our proposed method.
- Published
- 2017
36. The influences of circular saws with sawteeth of mic-zero-degree radial clearance angles on surface roughness in wood rip sawing
- Author
-
Zhankuan Zhang, Li Weiguang, Li Bo, and Xiaorui Peng
- Subjects
040101 forestry ,Surface (mathematics) ,Materials science ,Radial clearance angle ,Ecology ,Side edge ,[SDV]Life Sciences [q-bio] ,Forestry ,04 agricultural and veterinary sciences ,02 engineering and technology ,Sawtooth wave ,Mechanics ,Edge (geometry) ,021001 nanoscience & nanotechnology ,Radial clearance ,Quality (physics) ,Surface roughness ,0401 agriculture, forestry, and fisheries ,Point (geometry) ,Degree (angle) ,0210 nano-technology ,Sawtooth ,Wood sawing - Abstract
International audience; AbstractKey messageThe sawtooth parameters of the side edges likely affect surface roughness to a large extent in wood sawing. Our results point out the need to optimize the parameters of the side edges in order to maximize wood surface quality.ContextImproving surface roughness of wood in rip sawing by optimizing the sawtooth parameters is a significant topic of focus in the research of wood processing. However, existing research focuses mainly on the optimization of the sawtooth parameters of the major cutting edges without taking into account the influences of length and angle of the side edges on surface roughness. Thus, adaptive parameters for the side edges should be proposed.AimsThis study analyzes how the different parameters of side edges influence surface roughness when circular saws are used, and aims to resolve disparities between high feed speeds and better surface roughness.MethodsIn particular, this article presents the use of a sawtooth with a mic-zero-degree radial clearance angle. Northeast China ash (Fraxinus spp.) serves as the material for conducting this rip-sawing experiment. Nine types of sawtooth geometries at different feed speeds are used to study the influences of both the different radial clearance angles and the straight length of the zero-degree radial clearance angle on surface roughness (Ra).ResultsSurface roughness increases with the increase in feed speed, and the smaller the radial clearance angle of the sawteeth, the smaller the surface roughness. When the sawteeth have a mic-zero-degree radial clearance angle, the sawing surface roughness is lower than that of the value of sawteeth with radial clearance angles, especially when the straight length of the zero-degree radial clearance increases from 0 to 0.5 mm, in which case the decrease is most obvious.ConclusionSurface roughness depends, to a certain extent, on the depth of the saw notch. A small part of the side edge that forms the sawing surface participates in the actual cutting, and the length of this section is approximately equal to the feed per tooth. Sawteeth with mic-zero-degree radial clearance angles can improve the surface quality of sawing. Also, if the other cutting factors remain unchanged, surface roughness can be improved and friction can be reduced between the side edges and the wood by increasing the feed speed.
- Published
- 2017
37. Visual predictive control from distance-based and Homography-based Features
- Author
-
Hao Wan, Li Weiguang, and Guoqiang Ye
- Subjects
0209 industrial biotechnology ,Optimization problem ,Pixel ,business.industry ,Feature extraction ,02 engineering and technology ,Visual servoing ,Model predictive control ,020901 industrial engineering & automation ,Feature (computer vision) ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,business ,Projection (set theory) ,Homography (computer vision) ,Mathematics - Abstract
This paper deals with the issue of improved performance for image based visual servoing combining features selection and constraints handling. Observed object is described as a set of 3D points, corresponding 2D pixel points features in camera view are extracted and transformed to spherical point features through a virtual projection process; then, a set of six independent visual features combining distance-based and Homography-based Features, is determined and the related feature Jacobian is calculated. After features selection, image based visual servoing (IBVS) is formulated into a constrained optimization problem by nonlinear model predictive control (NMPC) method. Visibility constraints, 3D velocities constraints and 3D task space constraints are all considered in the optimization problem. Finally, simulations are provided and demonstrate the effectiveness and improved behavior of proposed method.
- Published
- 2016
38. Uncalibrated visual predictive control using Broyden estimation
- Author
-
Hao Wan, Guoqiang Ye, and Li Weiguang
- Subjects
0209 industrial biotechnology ,Robot kinematics ,Computer science ,business.industry ,Robotics ,02 engineering and technology ,Visual servoing ,Computer Science::Robotics ,Model predictive control ,symbols.namesake ,020901 industrial engineering & automation ,Control theory ,Jacobian matrix and determinant ,0202 electrical engineering, electronic engineering, information engineering ,symbols ,Object model ,Robot ,020201 artificial intelligence & image processing ,Artificial intelligence ,business - Abstract
in order to increase the flexibility and intelligence of robotics visual control system, Broyden estimation of composite Jacobian is combined with nonlinear model predictive control in robotics visual servoing. This method does not require the knowledge of robot model, camera model and object model, while visibility constraints, limitations of joint angles and joint velocities are all considered. Robotics control is achieved by solving the constrained optimization problem over a predictive horizon at each step, corresponding predictive model is designed with estimated composite Jacobian. Finally, simulation results are provided to demonstrate the validity of proposed method.
- Published
- 2016
39. Hip, knee and ankle motion angle detection based on inertial sensor
- Author
-
Li Weiguang, Sun Tongyang, Chen Haoqiu, Meng Li, Lu Zhixiang, Zhengzhi Wu, Hou Anxin, Lihong Duan, Yajing Shen, Lu Zhijiang, Quanquan Liu, Qihong Liu, Wei Chengdong, Chunbao Wang, and Chen Pengfang
- Subjects
0209 industrial biotechnology ,medicine.medical_specialty ,Inertial frame of reference ,Rehabilitation ,Computer science ,medicine.medical_treatment ,0206 medical engineering ,Motion detection ,02 engineering and technology ,Thigh ,020601 biomedical engineering ,Motion (physics) ,Euler angles ,symbols.namesake ,020901 industrial engineering & automation ,Physical medicine and rehabilitation ,medicine.anatomical_structure ,medicine ,symbols ,Rotation (mathematics) ,Gesture - Abstract
Up to now, with the increasing of the elderly population, more and more patients are suffering from hemiplegia. The need for hemiplegic rehabilitation is increasing quickly. As traditional rehabilitation, each patient must be treated by therapist, one by one. However, because of the different levels of therapists, the rehabilitation cannot be performed as the as the same. Normally, the rehabilitation status diagnosing is still be performed by therapists with the subjective experience. It caused the inhomogeneity on rehabilitation evaluation. It also sometimes causes negative influence on the rehabilitation effect. To solve these problems, many researches focusing on assessing the status of the hemiplegic patients quantitatively are proposed rehabilitation evaluation systems. Rehabilitation motion detection is the basis of the evaluation system, and it requires the participation of therapist. In this paper, a method is presented to detect lower limb motion of hemiplegic patients based on inertial sensor technology. The gesture quaternion of lower limb can be obtained through LPMS. With the matrix and Euler angle changing algorithm, combining with the simplified lower limb motion model, the rotation angle of joint can be computed. Finally, the curve of rotation angle of knee is established.1
- Published
- 2016
40. Development of parallel mechanism with six degrees of freedom for ankle rehabilitation
- Author
-
Chen Haoqiu, Zhengzhi Wu, Jianjun Wei, Sun Tongyang, Qihong Liu, Zhuolin Yu, Meng Li, Quanquan Liu, Lu Zhixiang, Lihong Duan, Wei Chengdong, Hou Anxin, Chunbao Wang, Chen Pengfang, Lu Zhijiang, and Li Weiguang
- Subjects
0209 industrial biotechnology ,Engineering ,Rehabilitation ,business.industry ,medicine.medical_treatment ,020208 electrical & electronic engineering ,Degrees of freedom ,Body movement ,02 engineering and technology ,Training effect ,Mechanism (engineering) ,020901 industrial engineering & automation ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Robot ,Six degrees of freedom ,business ,Programmer ,Simulation - Abstract
With the aging population problem getting more and more aggravated, the number of hemiplegia patients increases rapidly, which results in the increasing requirement of rehabilitation training for regaining the body movement function. Taking advantages of rehabilitation robots makes the rehabilitation training more scientific and efficient compared to traditional rehabilitation measures such as manual training. By now, many types of rehabilitation robots have been proposed by researchers. However, from the view of the physiological structure, many of them can't well fit the motion characteristics. Ankle plays an important role in standing, walking and so on. As the motion of these robots is different from the motion characteristics of ankles, it would make an undesired influence on the training effect. Rehabilitation robots have many structures, and they are mainly serial mechanism and parallel mechanism. However, serial mechanism is inconvenient to package. In this paper, a new type of parallel mechanism with six degrees of freedom is proposed. The basic principle structure of the ankle rehabilitation robot in this paper would be done according to the medical requirement and engineering requirement. After determine the programmer of the mechanism, the degrees of freedom of the mechanism would be calculated by the screw theory, and the Solid works software would be used to simulate and analyze the movement of the mechanism so that the torque and power calculation of key positions of the mechanism would be done with the simulation data. At last, the specific design of the mechanism would be finished with the obtained feasible basic principle structure. The function of different components would be introduced and this paper would check the key components to ensure the reliability of the mechanism.
- Published
- 2016
41. Development of a 3 freedom ankle robot to assist the rehabilitation training
- Author
-
Quanquan Liu, Lihong Duan, Qing Shi, Sun Tongyang, Meng Li, Yajing Shen, Chunbao Wang, Zhengzhi Wu, Jianjun Long, Jianjun Wei, Li Weiguang, and Yulong Wang
- Subjects
0209 industrial biotechnology ,Engineering ,medicine.medical_treatment ,02 engineering and technology ,030204 cardiovascular system & hematology ,Degrees of freedom (mechanics) ,Field (computer science) ,03 medical and health sciences ,020901 industrial engineering & automation ,0302 clinical medicine ,medicine ,Torque ,Simulation ,Rehabilitation ,business.industry ,technology, industry, and agriculture ,Robotics ,body regions ,surgical procedures, operative ,medicine.anatomical_structure ,Control system ,Robot ,Artificial intelligence ,Ankle ,business ,human activities - Abstract
With the developments of robotics, more and more rehabilitation robots are used to assist traditional training in rehabilitation field. In this paper, a novel ankle robot combined with 3 degrees of freedom, full fill passive-active training, subjective awareness and objective training requirements was proposed. The requirement of ankle robot was analyzed based on the ankle physical structure and real rehabilitation. Based on traditional rehabilitation therapy, a novel robot-assist rehabilitation therapy to combine subjective awareness with objective training was proposed. In this robot, a novel mechanism structure of cross-circle was proposed to robot movement around ankle center. The mechanical structure includes four parts, adduction/abduction parts, dorsiflexion/plantar flexion parts, inversion/eversion parts and sensing unit. Each part of ankle rehabilitation robot was introduced in detail. Finally, the core control strategy, position control and force control were proposed. With the robot, several primary experiments are performed. The feasibility of the robot was verified.
- Published
- 2016
42. Nonlinear model predictive control for visual servoing from a set of points
- Author
-
Hao Wan, Guoqiang Ye, and Li Weiguang
- Subjects
0301 basic medicine ,0209 industrial biotechnology ,Optimization problem ,business.industry ,Computer science ,030106 microbiology ,02 engineering and technology ,Image plane ,Visual servoing ,03 medical and health sciences ,Improved performance ,symbols.namesake ,Model predictive control ,020901 industrial engineering & automation ,Constrained optimization problem ,Nonlinear model ,Jacobian matrix and determinant ,symbols ,Computer vision ,Artificial intelligence ,business - Abstract
From a set of points in the image plane, six independent image features are designed with nice decoupling and linear properties. Then, nonlinear model predictive control is used to redefine the visual servoing as a constrained optimization problem, where local predictive model is designed based on image jacobian. The necessarity of field-of-view constraint is deceased, thanks to proposed strategy for recovery of disappearing matched point features by projection homography. This helps to reduce the unknown parameters in the optimization problem. On the other hand, proposed constrained visual servoing control is expected to perform well in task space because of selected features. Finally, simulation results are presented to illustrate the effectiveness and improved performance of proposed method.
- Published
- 2016
43. Development of an ankle robot MKA-III for rehabilitation training
- Author
-
Sun Tongyang, Zhengzhi Wu, Lihong Duan, Lu Zhijiang, Chunbao Wang, Yulong Wang, Meng Li, Yajing Shen, Atsuo Takanishi, Li Weiguang, Qing Shi, Jianjun Long, Quanquan Liu, and Jianjun Wei
- Subjects
0209 industrial biotechnology ,medicine.medical_specialty ,Computer science ,medicine.medical_treatment ,02 engineering and technology ,030204 cardiovascular system & hematology ,Degrees of freedom (mechanics) ,Field (computer science) ,03 medical and health sciences ,020901 industrial engineering & automation ,0302 clinical medicine ,Physical medicine and rehabilitation ,medicine ,Mechanism design ,Rehabilitation ,business.industry ,technology, industry, and agriculture ,Robotics ,body regions ,medicine.anatomical_structure ,Control system ,Robot ,Artificial intelligence ,Ankle ,business ,human activities - Abstract
With the developments of robotics, it has become a fashion trend that ankle rehabilitation robots assist traditional training in rehabilitation field. In this thesis, a novel ankle robot combing with 3 degrees of freedom, combining passive-active training, subjective awareness and objective training was proposed. Prior to robot developments, the requirement of ankle robot was analyzed based on the ankle structure and rehabilitation. In order to acquire the range of ankle motion, an experiment was established to detect the physiological data. Based on traditional rehabilitation therapy, a novel robot-assist rehabilitation therapy combing subjective awareness and objective training was proposed. Based on the requirements analysis, a novel mechanism structure of cross-circle was proposed to robot movement around ankle center. The mechanical structure includes four parts, adduction/abduction parts, dorsiflexion/plantar flexion parts, inversion/eversion parts and sensing unit. Each part of ankle rehabilitation robot was introduced in detail. By means of stress analysis and strength check, the feasibility of the structure was verified. After the mechanism design, the hardware configuration of control system was built up. Finally, the core control strategy, position control and force control were proposed.
- Published
- 2016
44. Development of a new parallel mechanism with five degrees of freedom for ankle rehabilitation
- Author
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Zhengzhi Wu, Li Mengjie, Li Weiguang, Jian Qin, Lihong Duan, Jianjun Wei, Jianjun Long, Yajing Shen, Qing Shi, Z.l. Yu, R.x. Luo, Chunbao Wang, Quanquan Liu, Lu Zhijiang, Sun Tongyang, Yulong Wang, and H.q. Chen
- Subjects
0209 industrial biotechnology ,Engineering ,Rehabilitation ,business.industry ,medicine.medical_treatment ,Degrees of freedom (statistics) ,Body movement ,02 engineering and technology ,Training effect ,Motion (physics) ,020501 mining & metallurgy ,Mechanism (engineering) ,020901 industrial engineering & automation ,0205 materials engineering ,Screw theory ,medicine ,Robot ,business ,Simulation - Abstract
With the aging population problem getting more and more aggravated, the number of hemiplegia patients increases rapidly, which results in the increasing requirement of rehabilitation training for regaining the body movement function. Taking advantages of rehabilitation robots makes the rehabilitation training more scientific and efficient compared to traditional rehabilitation measures such as manual training. By now, many types of rehabilitation robots have been proposed by researchers. However, from the view of the physiological structure, many of them can't well fit the motion characteristics. Ankle plays an important role in standing, walking and so on. As the motion of these robots is different from the motion characteristics of ankles, it would make an undesired influence on the training effect. Rehabilitation robots have many structures, and they are mainly serial mechanism and parallel mechanism. However, serial mechanism is inconvenient to package. In this paper, a new type of parallel mechanism with five degrees of freedom was proposed. Compared to serial mechanism, parallel mechanism is convenient to package and it has larger motion area. It enables ankles to rotate around the rotary center of the ankle. With the screw theory, the degree of freedom was calculated. To verify the working space of the mechanism, the working space simulation was carried out by Matlab. Finally, the quantity and position of motors are determined.
- Published
- 2016
45. Development of a robot MKW-II for hand and wrist rehabilitation training
- Author
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Quanquan Liu, Li Mengjie, Lihong Duan, Jian Qin, Zhengzhi Wu, H.q. Chen, Jianjun Long, Qing Shi, Sun Tongyang, Z.l. Yu, Yajing Shen, R.x. Luo, Yulong Wang, Chunbao Wang, Lu Zhijiang, Jianjun Wei, and Li Weiguang
- Subjects
Ageing society ,medicine.medical_specialty ,Engineering ,Rehabilitation ,business.industry ,medicine.medical_treatment ,media_common.quotation_subject ,Rehabilitation robot ,Training (civil) ,Wrist rehabilitation ,Neglect ,Physical medicine and rehabilitation ,Rehabilitation training ,medicine ,Robot ,business ,media_common - Abstract
With the aggravation of ageing society, the number of hemiplegic patients has increased rapidly. As a result, the requirement of rehabilitation training has made a huge increase. In order to help hemiplegic patients to get a better rehabilitation and help occupational therapists to reduce working pressure, series of rehabilitation training robot has been developed. Although the rehabilitation robot has been improved greatly for meeting various requirements, most of rehabilitation robots still just focus on rehabilitation training of single joint and neglect the recovery of damaged nervous system. In order to offer patients comprehensive rehabilitation training and help recovering nervous system, a new MKW series rehabilitation robots are designed to realize wrist and hand independent and cooperative training in our team. As the MKW-I is not convenient for use and its sensors' accuracy would be heavily influenced by environment. Therefore, MKW-II is designed for better rehabilitation effectiveness. For these reasons, we propose the MKW-II, which can perfectly solve these problems. The improvement of mechanism structure and improvement of related sensors will be introduced detailly in this paper.
- Published
- 2016
46. Development of lower limb rehabilitation evaluation system based on virtual reality technology
- Author
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Yajing Shen, Haojian Lu, Chang Gao, Yong Zhao, Zhengzhi Wu, Li Weiguang, Chunbao Wang, Atsuo Takanishi, Jianjun Long, Shihui Shen, Massimiliano Zecca, Jian Qin, Qing Shi, Yulong Wang, Quanquan Liu, and Sun Tongyang
- Subjects
030506 rehabilitation ,medicine.medical_specialty ,Rehabilitation ,Research groups ,Computer science ,medicine.medical_treatment ,Medical rehabilitation ,Rehabilitation evaluation ,Virtual reality ,Lower limb ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Rehabilitation training ,medicine ,Robot ,030212 general & internal medicine ,0305 other medical science ,Simulation - Abstract
Nowadays, with the development of the proportion of the elderly population in the world, several problems caused by the population aging gradually into people's horizons. One of the biggest problems plagued the vast majority of the elderly is hemiplegia, which leads to the vigorous development of the physical therapists. However, these traditional methods of physical therapy mainly rely on the skill of the physical therapists. In order to make up the defects of traditional methods, many research groups have developed different kinds of robots for lower limb rehabilitation training but most of them can only realize passive training which cannot adopt rehabilitation training based on the patients' individual condition effectively and they do not have a rehabilitation evaluation system to assess the real time training condition of the hemiplegic patients effectively. In order to solve the problems above, this paper proposed a lower limb rehabilitation evaluation system which is based on the virtual reality technology. This system has an easy observation of the human-computer interaction interface and the doctor is able to adjust the rehabilitation training direct at different patients in different rehabilitation stage based on this lower limb rehabilitation evaluation system. Compared with current techniques, this novel lower limb rehabilitation evaluation system is expected to have significant impacts in medical rehabilitation robot field.
- Published
- 2016
47. Mechanism design of an ankle robot MKA-III for rehabilitation training
- Author
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Qing Shi, Lihong Duan, Zhengzhi Wu, Yajing Shen, Meng Li, Yulong Wang, Li Weiguang, Sun Tongyang, Jianjun Wei, Lu Zhijiang, Lu Zhixiang, Jian Qin, Chunbao Wang, Jianjun Long, and Quanquan Liu
- Subjects
0209 industrial biotechnology ,Mechanism design ,Engineering ,medicine.medical_specialty ,Rehabilitation ,business.industry ,medicine.medical_treatment ,Motor control ,02 engineering and technology ,Aging society ,030204 cardiovascular system & hematology ,Plantar flexion ,body regions ,03 medical and health sciences ,020901 industrial engineering & automation ,0302 clinical medicine ,medicine.anatomical_structure ,Physical medicine and rehabilitation ,Rehabilitation training ,medicine ,Robot ,Ankle ,business - Abstract
With the development of aging society, the number of hemiplegia patients grows rapidly and over 75% of survivors suffering hemiplegia need rehabilitation training. To assist therapists, series of rehabilitation training robots were carried out. However, most of current researches are only focusing on function training. They ignore the importance of neurological rehabilitation in early phrase of hemiplegia. Early rehabilitation takes a fundamental position in neurological rehabilitation and whole-body rehabilitation. To fulfill all of those requirements, MKA series have been developed. During the experiment, there is some problems including unreliable transmission and dehumanization design. For these reasons, in this paper, we propose the MKA-III. Based on physiological structure and rehabilitation theory, the mechanism was design. In this paper, the detail design of the mechanism is introduced. The mechanical structure includes four parts, adduction/abduction parts, dorsiflexion/plantar flexion parts, inversion/eversion parts and sensing unit. Each part of ankle rehabilitation robot was introduced in detail. In addition, for the motor control and information acquisition, the hard system is introduced.
- Published
- 2016
48. Development of lower limb motion detection based on LPMS
- Author
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Sun Tongyang, Meng Li, Yulong Wang, Qing Shi, Qihong Liu, Jian Qin, Lihong Duan, Quanquan Liu, Yajing Shen, Lu Zhijiang, Li Weiguang, Chunbao Wang, Chen Pengfang, Zhengzhi Wu, and Jianjun Wei
- Subjects
0209 industrial biotechnology ,medicine.medical_specialty ,Rehabilitation ,Computer science ,Quaternions and spatial rotation ,medicine.medical_treatment ,0206 medical engineering ,Wearable computer ,Motion detection ,02 engineering and technology ,020601 biomedical engineering ,Motion (physics) ,020901 industrial engineering & automation ,Physical medicine and rehabilitation ,medicine ,Robot ,Quaternion ,Rotation (mathematics) ,Simulation - Abstract
Up to now, with the increasing of the elderly population, more and more patients are suffering from hemiplegia. It leads to a great need for hemiplegic rehabilitation. In traditional rehabilitation, each patient must be treated by therapist, one by one. However, since the individual differences of therapists, no effectiveness rehabilitation is guaranteed. And the rehabilitation status of patient is still diagnosed by therapists with their subjective experience. This would cause the inhomogeneity on rehabilitation evaluation and sometimes negative influence on the rehabilitation effect. To solve these problems, many research groups proposed rehabilitation evaluation systems to assess the status of the hemiplegic patients quantitatively. Rehabilitation motion detection is the basis of the evaluation system, and it requires the participation of therapist. However, many motion detection methods do not meet the detection requirements, such as mechanical tracking and optical sensor, etc. In this article we present a method to detect lower limb motion of hemiplegic patients based on inertial sensor technology. LPMS, a high performance, easy wearable, portable and large measurement range sensor, is selected as the motion sensor. We obtain the gesture quaternion of lower limb through LPMS, and then use the algorithm to convert quaternion to matrix and Euler angle. Combining with the simplified lower limb motion model, we compute the rotation angle of joint by processing the rotation quaternion in Matlab. Finally, the curve of rotation angle of knee is established. The method detecting the motion of lower limb can be integrated into the rehabilitation robot control system, realizing intelligent detection and evaluation. Thus, the rehabilitation robots could be expected adjusting training parameters based on patient status automatically, expected to have significant impacts in medical rehabilitation robot field.
- Published
- 2016
49. Gait motion analysis based on WB-4 sensor with quaternion algorithm
- Author
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Sun Tongyang, M. Li, C.d. Wei, Massimiliano Zecca, A.h. Hou, Y.l. Wang, P.f. Chen, Li Weiguang, J.j. Long, Q.q. Liu, Jian Qin, Yajing Shen, Qing Shi, Chunbao Wang, L.h. Duan, Zhengzhi Wu, Qihong Liu, Jianjun Wei, and Lu Zhijiang
- Subjects
0209 industrial biotechnology ,Motion analysis ,Rehabilitation ,Computer science ,medicine.medical_treatment ,0206 medical engineering ,Motion detection ,02 engineering and technology ,020601 biomedical engineering ,Motion (physics) ,Euler angles ,symbols.namesake ,020901 industrial engineering & automation ,Gait (human) ,symbols ,medicine ,Quaternion ,Rotation (mathematics) ,Algorithm - Abstract
Up to now, with the increasing of the elderly population, more and more patients are suffering from hemiplegia. The needs for hemiplegic rehabilitation is increasing quickly. As traditional rehabilitation, each patient must be treated by therapist, one by one. However, because of the different levels of therapists, the rehabilitation cannot be performed as the as the same. Normally, the rehabilitation status diagnosing is still be performed by therapists with the subjective experience. It caused the inhomogeneity on rehabilitation evaluation. It also sometimes causes negative influence on the rehabilitation effect. To solve these problems, many researches focusing on assessing the status of the hemiplegic patients quantitatively are proposed rehabilitation evaluation systems. Rehabilitation motion detection is the basis of the evaluation system, and it requires the participation of therapist. In this paper, a method is presented to detect lower limb motion of hemiplegic patients based on inertial sensor technology. The gesture quaternion of lower limb can be obtained through LPMS. With the matrix and Euler angle changing algorithm, combining with the simplified lower limb motion model, the rotation angle of joint can be computed. Finally, the curve of rotation angle of knee is established.
- Published
- 2016
50. Novel hybrid IBVS based on the unified projection model
- Author
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Zhen Li, Hao Wan, Guoqiang Ye, and Li Weiguang
- Subjects
0209 industrial biotechnology ,Robot kinematics ,business.industry ,Perspective (graphical) ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Robotics ,02 engineering and technology ,03 medical and health sciences ,Error function ,020901 industrial engineering & automation ,0302 clinical medicine ,Control theory ,030220 oncology & carcinogenesis ,Control system ,Robot ,Computer vision ,Artificial intelligence ,business ,Mathematics ,Homography (computer vision) - Abstract
In this paper, a novel hybrid IBVS method is proposed to improve the performance of robotics visual control system. In this work, we only consider image features to define the error function. Based on the unified projection model, features are selected to control full-DOF motion of the robot. Spherical projected features are used to control the translational motion, while perspective projected features are used to control the rotational motion. These hybrid projected features ensure nice decoupled properties in control system. In all, two sets of features are proposed to design the IBVS controller. One is based on homography-based features, the other is based on moment invariants features. Simulation results are provided to illustrate the effectiveness and optimal performance of the proposed method.
- Published
- 2016
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