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Various rehabilitation robots have been developed to assist the movement training of the upper limbs of stroke patients, among which some have been used to evaluate the motor recovery. However, how to understand the recovery of motor function from the quantitative assessment following robot-assisted rehabilitation training is still not clear. The objective of this study is to propose a quantitative assessment method of motor function based on the force and trajectory characteristics during robotic training to reflect motor functional recovery. To assist stroke patients who are not able to move voluntarily, an assistive training mode was developed for the robot-assisted rehabilitation system based on admittance control. Then, to validate the relationship between characteristic information and functional recovery, a clinical experiment was conducted, in which nine stroke patients and nine healthy subjects were recruited. The results showed a significant difference in movement range and movement smoothness during trajectory tracking tasks between stroke patients and healthy subjects. The two parameters above have a correlation with the Fugl-Meyer Assessment for Upper Extremity (FMU) of the involved patients. The multiple linear regression analysis showed FMU was positively correlated with parameters (R2=0.91,p&lt, 0.005). This finding indicated that the above-mentioned method can achieve quantitative assessment of motor function for stroke patients during robot-assisted rehabilitation training, which can contribute to promoting rehabilitation robots in clinical practice.

Dual-electrode capacitively coupled plasma discharges are investigated here to lower the non-uniformity of plasma density. The dual-electrode structure proposed by Jung splits the electrode region and increases the flexibility of fine tuning non-uniformity. Different RF voltages, frequencies, phase-shifts and electrode areas are simulated and the influences are discussed. RF voltage and electrode area have a non-monotonic effect on non-uniformity, while frequency has a monotonic effect. Phase-shift has a cyclical influence on non-uniformity. A special combination of 224 V voltage and 11% area ratio with 10 MHz lowers the non-uniformity of the original set (200 V voltage and 0% area ratio with 10 MHz) by 46.5%. The position of the plasma density peak at the probe line has been tracked and properly tuning the phase-shift can obtain the same trace as tuning frequency or voltage.

Objective To investigate trunk muscle activity patterns in a person with thoracic spinal cord injury when walking with different un-powered exoskeletons, and to explore how different un-powered exoskeletons affect trunk muscle activity patterns. Case report Data were recorded from a subject with complete spinal cord injury at T10, using an electromyography system on 4 pairs of trunk muscles and a motion capture system simultaneously. Results The participant generated large muscle force to laterally bend and rotate trunk, and swung his leg through the moments generated, not only by trunk flexion and extension, but by trunk rotation. In an energy-stored exoskeleton without springs condition, the energy generated by erector spinae contraction was stored in the energy-stored component in the stance phase and released in the swing phase to compensate for energy generated by the obliquus externus abdominis and avoid overuse of the obliquus externus abdominis. Conclusion These findings prompt further development of un-powered exoskeletons and investigation into trunk muscle functions in patients with spinal cord injury when walking with un-powered exoskeletons.

An organism grows from very small to the whole body, while an engineering product is assembled from elements. An organism is formed autonomously and adaptable to his/her/its environment, while an engineering product can only execute very limited actions. The formation of a product determines its functionality. Nature is the best teacher for learning how structures are formed for specific functionality. This paper compares the design process with the developmental process of embryo and proposes a qualitative development framework that simulates the gene transcription and translation in biology. The key step in design is transforming behaviors to structures. This is a process from information to the form and it bears some similarity with the process from DNA to the protein in embryogenesis. Three basic steps are required from DNA to the protein: gene transcription, transport and protein synthesis, which is named as gene expression. Key mechanisms contributing to this transformation process are investigated and a qualitative development framework are constructed for a growth design process. Simple examples are presented for illustration of proposed methods.Copyright © 2015 by ASME

Robot-assisted therapy has been proved more effective for treating neurological conditions than conventional therapy. It is known that early training can enhance motor learning and improve functional abilities more than chronicphase training. But there is almost no such lower-limb rehabilitation robot for patients within three months after stroke in clinical. This article introduces such a new robot for acute and subacute stroke patients, which can increase joint flexibility, prevent muscle disuse atrophy, help neural plasticity, enhance motor learning and improve functional abilities by providing patients simulating-gait-training. We did randomized controlled trials including total 8 subjects (4 healthy, 4 patients). At the end of rehabilitation training, the patients’ conditions were assessed by nursing and training staff using the Fugl-Meyer Assessment score. After four weeks of robot-assisted therapy, experimental results showed that the patients’ score and their activities of daily living improved a lot. It is proved that the lower-limb rehabilitation robot for acute and subacute patients is effective.

It is generally accepted that early treatment is an effective way in improving body’s function of the stroke patients. This paper reviews the background of the rehabilitation theory and some typical products of lower limb rehabilitation robots. Lower limb rehabilitation robots have been drawn into rehabilitation training. Researchers have done large amounts of rehabilitation training experiments based on these rehabilitation robots. This paper reviews some representative articles. Abundant clinical trials show that robot-assisted rehabilitation therapy is more effective than conventional therapy in Functional Ambulatory Capacity (FAC), walking speed, step length, etc. However, there are few lower limb rehabilitation robots directing at patients in early stage (the first 3 months after illness) in the domestic and international markets. Therefore, lower limb rehabilitation robot for acute and subacute stroke patients is a promising research area in the future.

Quantitative evaluation for estimating motor function is a prerequisite for clinical application of rehabilitation robot. The current clinical evaluations, such as Fugl-Meyer assessment, still have some deficiency. The study provided an innovative evaluation method, which contrasted the physiological character of impaired limb with the contralateral upper limb of post stroke hemiplegic patients, and investigate the comparability of surface Electromyography (sEMG) between patients and healthy persons during robot-assisted motor recovery training possess similar track and equivalent velocity. There is much comparability of sEMG characteristic in healthy limb of patients compare with healthy person, yet less comparability exist in the impaired limb. The results in the study imply that the method depend on contralateral limb sEMG characteristic have potential capacity in clinical quantitative evaluation of rehabilitation and may competent to associate with other physiological character.

A convenient designing tool is developed aiming at providing a Thinking Assistant for innovative and creative designing. The tool is easy to develop by a designer himself following his own thought pattern. Neural networks are used to develop potential new structure patterns by changing connection properties of substructures. Design examples are provided to validate the method.

Our goal is to apply robotics and automation technology to assist, quantify, enhance, and verify neuro-rehabilitation. In this paper a novel robot neuro-rehabilitation for upper limb, with many merits, is developed. Mechanism and control of the robot are introduced in detail. By a clinical trial involving 30 stroke patients with three months at Rehabilitation Center of China, some results are obtained 1) robot-aided therapy does not have adverse effects, 2) patients can accept the procedure, 3) the therapy may reduce muscular tension, and 4) manipulation of the impaired upper limb may influence brain recovery. Some new ideas are also presented to make rehabilitation therapy more effectively. These ideas will be helpful to further quicken the development of the robot neuro-rehabilitation.

Joint clearance is one of important factors which affect motion precision of machines. In this paper the mathematical model of a new-type joint, tripod-ball sliding joint, is established, and the new concepts of basal system and active system are put forward. Based on the mode-change criterion established here, the consistent equations of motion in full-scale are derived by using Kane method. The dynamic behavior of the crank-slider mechanism with clearance in the tripod-ball sliding joint is investigated. The results including motion error and impact acceleration are obtained and the advantage of this new joint is shown.

In order to estimate the effect of neural rehabilitation robot for improving the upper extremity motor function, 23 hemiplegia patients who are BrunnstromTII at least receive clinical rehabilitation training by the upper extremity compound movements rehabilitation training robot. The assistance models of the neural rehabilitation robot and the programming of the clinical rehabilitation training are studied in this dissertation. The clinical assessment results make clear that after a period of rehabilitation treatment, the function of most patients, which could be assessed by Fugl-Meyer method, improved to a certain extent, and the rehabilitation effect is better than the traditional rehabilitation training. The outcome indicates that, the upper extremity compound movements rehabilitation training robot has a significant application prospect in clinical rehabilitation.

In order to improve the effect of robotic rehabilitation therapy, we need to find out which elements of robot training influence it. Our aim is to analysis the relation between the patients-active force and the effect. This paper reviews a clinical therapy involving 6 hemiplegia patients with the upper extremity compound movements rehabilitation training robot developed by Tsinghua University, Beijing. By processing the collected data, we get the evidence that the elevated scores after training and the patients' active force are high correlated. The larger the patient's active force, the better the training effect.

As one of the core components of IC manufacturing equipment, the electrostatic chuck (ESC) has been widely applied in semiconductor processing such as etching, PVD and CVD. The clamping force of the ESC is one of the most important technical indicators. A multi-physics simulation software COMSOL is used to analyze the factors influencing the clamping force. The curves between the clamping force and the main parameters such as DC voltage, electrode thickness, electrode radius, dielectric thickness and helium gap are obtained. Moreover, the effects of these factors on the clamping force are investigated by means of orthogonal experiments. The results show that the factors can be ranked in order of voltage, electrode radius, helium gap and dielectric thickness according to their importance, which may offer certain reference for the design of ESCs.

Clearance is inevitable in the kinematic joints of mechanisms. In this paper the dynamic behavior of a crank-slider mechanism with clearance in its tripod-ball sliding joint is investigated theoretically and experimentally. The mathematical model of this new-type joint is established, and the new concepts of basal system and active system are put forward. Based on the mode-change criterion established in this paper, the consistent equations of motion in full-scale are derived by using Kane method. The experimental rig was set up to measure the effects of the clearance on the dynamic response. Corresponding experimental studies verify the theoretical results satisfactorily. In addition, due to the nonlinear elements in the improved mathematical model of the joint with clearance, the chaotic responses are found in numerical simulation.