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When learning to use a brain-machine interface (BMI), the brain modulates neuronal activity patterns, exploring and exploiting the state space defined by their neural manifold. Neurons directly involved in BMI control (i.e., direct neurons) can display marked changes in their firing patterns during BMI learning. However, the extent of firing pattern changes in neurons not directly involved in BMI control (i.e., indirect neurons) remains unclear. To clarify this issue, we localized direct and indirect neurons to separate hemispheres in a task designed to bilaterally engage these hemispheres while animals learned to control the position of a platform with their neural signals. Animals that learned to control the platform and improve their performance in the task shifted from a global strategy, where both direct and indirect neurons modified their firing patterns, to a local strategy, where only direct neurons modified their firing rate, as animals became expert in the task. Animals that did not learn the BMI task did not shift from utilizing a global to a local strategy. These results provide important insights into what differentiates successful and unsuccessful BMI learning and the computational mechanisms adopted by the neurons.

Background: Hypertension (HT) is a common chronic disease in older adults. It not only leads to dizziness and other symptoms affecting balance in older adults with HT but also affects the hemodynamics of the cerebral cortex. At present, potential neural mechanisms of balance control in older adults with HT are still unclear. Therefore, this study aimed to explore the differences in the center of pressure (COP) and cerebral cortex activation between older adults with HT and normotension (NT) during standing balance tasks. This study May provide guidance for the early detection of the risk of falls among older adults with HT and the development of clinical rehabilitation strategies. Methods: In this cross-sectional study, 30 older adults with NT (NT group) and 27 older adults with HT (HT group) were subjected to three conditions: task 1, standing with eyes open on a stable surface; task 2, standing with eyes closed on a stable surface; and task 3, standing with eyes open on the surface of the foam pad. Cortical hemodynamic reactions were measured using functional near-infrared spectroscopy, and COP parameters were measured using a force plate. Results: The mean velocity of the COP in the medial–lateral direction in the NT group was significantly higher than that in the HT group (F  =  5.955, p  =  0.018) during task 3. When proprioception was disturbed, the activation of the left premotor cortex and supplementary motor cortex in the HT group was significantly lower than that in the NT group (F  =  14.381, p  <  0.001). Conclusion: The standing balance function of older adults with HT does not appear to be worse based on COP parameters than those of older adults with NT. This study revealed that the changes in the central cortex related to standing balance appear to be more indicative of balance control deficits in older adults with HT than changes in peripheral COP parameters, suggesting the importance of the early evaluation of cortical activation in older adults with HT at risk of falls. [ABSTRACT FROM AUTHOR]

Despite the abundance of studies on the control of standing balance, insights about the roles of biomechanics and neural control have been limited. Previous work introduced an analysis combining the direction and orientation of foot-ground forces. The "intersection point" of the lines of actions of these forces exhibited a consistent pattern across healthy, young subjects when computed for different frequency components of the center of pressure signal. To investigate the control strategy of quiet stance, we applied this intersection point analysis to experimental data of 15 healthy, young subjects balancing in tandem stance on a narrow beam and on the ground. Data from the sagittal and frontal planes were analyzed separately. The task was modeled as a double-inverted pendulum controlled by an optimal controller with torque-actuated ankle and hip joints and additive white noise. To test our prediction that the controller that minimized overall joint effort would yield the best fit across the tested conditions and planes of analyses, experimental results were compared with simulation outcomes. The controller that minimized overall effort produced the best fit in both balance conditions and planes of analyses. For some conditions, the relative penalty on the hip and ankle joints varied in a way relevant to the balance condition or to the plane of analysis. These results suggest that unimpaired quiet balance in a challenging environment can be best described by a controller that maintains minimal effort through the adjustment of relative ankle and hip joint torques. NEW & NOTEWORTHY: This study explored balance control in humans during a challenging task using the novel intersection point analysis, based on foot-ground force direction and point of application. Experimental data of subjects standing on a narrow beam in tandem stance were compared with modeling results of a double-inverted pendulum. The analysis showed that individuals minimized effort by adjusting ankle and hip torques, shedding light on the interplay of biomechanics and neural control in maintaining balance. [ABSTRACT FROM AUTHOR]

Chronic heart failure (CHF) is a complex clinical syndrome, associated with frailty, higher fall rates, and frequent hospitalizations. Heart Failure (HF) and preserved ejection fraction (HFpEF) is defined as a condition where a patient with HF have a diagnosis of left ventricular ejection fraction (LVEF) of ≥ 50%. The risk of HFpEF increases with age and is related to higher non-cardiovascular mortality. The aim of this study was to evaluate static balance and examine the effect of task difficulty on the discriminating power of balance control between patients with HFpEF (Patients with HFpEF) and their healthy controls. Moreover, the associations between static balance parameters, balance confidence, falls, lean muscle mass, and strength were assessed. Seventy two patients with HFpEF (mean age: 66.0 ± 11.6 years) and seventy two age- and gender-matched healthy individuals (mean age: 65.3 ± 9.5 years) participated in this study. Participants underwent a 30 s bilateral stance (BS) test and a 20 s Tandem-Romberg stance (TRS) on a force platform, evaluating the Range and Standard Deviation of Center of Pressure (COP) displacement parameters in both axes. Balance confidence was evaluated by the Activities-Specific Balance Confidence (ABC) Scale, and the number of falls during the last year was recorded. Lower limb strength was measured using an isokinetic dynamometer, isometric leg strength, and a Sit-to-Stand test. Bioelectrical impedance analysis was conducted to assess lean fat mass, lean fat mass index, and lean%. Patients with HFpEF presented with lower static balance in BS and TRS compared to healthy controls (p < 0.05), lower balance confidence by 21.5% (p < 0.05), and a higher incidence of falls by 72.9% (p < 0.05). BS was a better descriptor of the between-group difference. Furthermore, static balance, assessed in controlled lab conditions, was found to have little if no relationship to falls, strength, lean muscle mass, and balance confidence. Although no correlation was noted between the static balance parameters and falls, the fall rate was related to balance confidence, age, muscle strength, and lean fat. [ABSTRACT FROM AUTHOR]

Background: Tai Chi (TC) holds a unique and valued place in promoting the physical and mental health of college students. Its significance is underscored by its incorporation as a compulsory physical education course in every university in China. TC, with its rich tradition, places a strong emphasis on posture control as a core sports ability. However, the students in Tai Chi Elective Course (TCEC) have very poor posture control ability. This study protocol investigates the potential of Tan Tui (TT) to address these issues, as TT is a fundamental skill for beginners of traditional Chinese martial arts and has a track record of enhancing lower limb strength and balance, making it a promising choice for improving posture control in TCEC. Methods/design: To investigate the impact of different intensities of TT exercises on posture control in TCEC students, we have designed a randomized, double-blind, parallel-controlled trial. Seventy-six students in the TCEC will be randomly divided into low-intensity Tan Tui (LTT), medium-intensity Tan Tui (MTT), and high-intensity Tan Tui exercises group (HTT) and control group (CON), each with 19 people. The LTT group, MTT group, and HTT group will be given different intensity of TT exercises, and the CON group will be given regular TCEC. The intervention period will be 6 weeks (2 times a week, 20 min each time). At baseline (before), 4 weeks of intervention (middle), and 6 weeks of intervention (after), the Unipedal Stance Test (UST), the Star Excursion Balance Test (SEBT), 60°/s angular velocity knee joint flexion and extension relative peak torque (RPT), and knee joint position perception (KJPP) will be evaluated. Discussion: This is the first randomized controlled trial protocol from the perspective of training intensity to evaluate the effect of different intensity of TT exercises on posture control of students in TCEC. Should our research reveal a significant intervention effect, the results will offer preliminary, higher-quality evidence supporting the positive impact of varying intensities of Tan Tui exercises on posture control in TCEC students. Trial registration: Chinese Clinical Trial Registry ChiCTR2000039109. Registered on October 17, 2020. [ABSTRACT FROM AUTHOR]

Visual information affects static postural control, but how it affects dynamic postural control still needs to be fully understood. This study investigated the effect of proprioception weighting, influenced by the presence or absence of visual information, on dynamic posture control during voluntary trunk movements. We recorded trunk movement angle and angular velocity, center of pressure (COP), electromyographic, and electroencephalography signals from 35 healthy young adults performing a standing trunk flexion–extension task under two conditions (Vision and No-Vision). A random forest analysis identified the 10 most important variables for classifying the conditions, followed by a Wilcoxon signed-rank test. The results showed lower maximum forward COP displacement and trunk flexion angle, and faster maximum flexion angular velocity in the No-Vision condition. Additionally, the alpha/beta ratio of the POz during the switch phase was higher in the No-Vision condition. These findings suggest that visual deprivation affects cognitive- and sensory-integration-related brain regions during movement phases, indicating that sensory re-weighting due to visual deprivation impacts motor control. The effects of visual deprivation on motor control may be used for evaluation and therapeutic interventions in the future. [ABSTRACT FROM AUTHOR]

Background: Changes in the trunk and lower limbs' sagittal movements may cause patellofemoral pain (PFP) because they influence the forces acting on this joint. Objectives: To compare trunk and lower limb sagittal kinematics between women with and without PFP during functional tests and to verify whether sagittal trunk kinematics are correlated with those of the knees and ankles. Methods: A total of 30 women with PFP and 30 asymptomatic women performed single-leg squat (SLS) and step-down (SD) tests and were filmed by a camera in the sagittal plane. The trunk inclination angle, forward knee displacement, and ankle angle were calculated. Results: The PFP group exhibited less trunk flexion (SLS, p =.006; SD, p =.016) and greater forward knee displacement (SLS, p =.001; SD, p =.004) than the asymptomatic group; there was no significant difference in ankle angle (SLS, p =.074; SD, p =.278). Correlation analysis revealed that decreased trunk flexion was associated with increased forward knee displacement (SLS, r = −0.439, p =.000; SD, r = −0.365, p =.004) and ankle dorsiflexion (SLS, r = −0.339, p =.008; SD, r = −0.356, p =.005). Conclusion: Women with PFP present kinematic alterations of the trunk and knee in the sagittal plane during unipodal activities. Furthermore, the trunk and lower limb sagittal movements were interdependent. [ABSTRACT FROM AUTHOR]

Abstract Background Tai Chi (TC) holds a unique and valued place in promoting the physical and mental health of college students. Its significance is underscored by its incorporation as a compulsory physical education course in every university in China. TC, with its rich tradition, places a strong emphasis on posture control as a core sports ability. However, the students in Tai Chi Elective Course (TCEC) have very poor posture control ability. This study protocol investigates the potential of Tan Tui (TT) to address these issues, as TT is a fundamental skill for beginners of traditional Chinese martial arts and has a track record of enhancing lower limb strength and balance, making it a promising choice for improving posture control in TCEC. Methods/design To investigate the impact of different intensities of TT exercises on posture control in TCEC students, we have designed a randomized, double-blind, parallel-controlled trial. Seventy-six students in the TCEC will be randomly divided into low-intensity Tan Tui (LTT), medium-intensity Tan Tui (MTT), and high-intensity Tan Tui exercises group (HTT) and control group (CON), each with 19 people. The LTT group, MTT group, and HTT group will be given different intensity of TT exercises, and the CON group will be given regular TCEC. The intervention period will be 6 weeks (2 times a week, 20 min each time). At baseline (before), 4 weeks of intervention (middle), and 6 weeks of intervention (after), the Unipedal Stance Test (UST), the Star Excursion Balance Test (SEBT), 60°/s angular velocity knee joint flexion and extension relative peak torque (RPT), and knee joint position perception (KJPP) will be evaluated. Discussion This is the first randomized controlled trial protocol from the perspective of training intensity to evaluate the effect of different intensity of TT exercises on posture control of students in TCEC. Should our research reveal a significant intervention effect, the results will offer preliminary, higher-quality evidence supporting the positive impact of varying intensities of Tan Tui exercises on posture control in TCEC students. Trial registration Chinese Clinical Trial Registry ChiCTR2000039109. Registered on October 17, 2020.

This paper describes the development of an in-pipe inspection robot system designed for large-diameter water pipes. The robot is equipped with a Magnetic Flux Leakage (MFL) sensor module. The robot system is intended for pipes with diameters ranging from 900 mm to 1200 mm. The structure of the in-pipe inspection robot consists of the front and rear driving parts, with the inspection module located centrally. The robot is powered by 22 motors, including eight wheels with motors positioned at both the bottom and the top for propulsion. To ensure that the robot's center aligns with that of the pipeline during operation, lifting units have been incorporated. The robot is equipped with cameras and LiDAR sensors at the front and rear to monitor the internal environment of the pipeline. Pipeline inspection is conducted using the MFL inspection modules, and the robot's driving mechanism is designed to execute spiral maneuvers while maintaining contact with the pipeline surface during rotation. The in-pipe inspection robot is configured with wireless communication modules and batteries, allowing for wireless operation. Following its development, the inspection robot underwent driving experiments in actual pipelines to validate its performance. The field test bed used for these experiments is approximately 1 km in length. Results from the driving experiments on the field test bed confirmed the robot's ability to navigate various curvatures and obstacles within the pipeline. It is posited that the use of the developed in-pipe inspection robot can reduce economic costs and enhance the safety of inspectors when examining aging pipes. [ABSTRACT FROM AUTHOR]

When learning to use a brain-machine interface (BMI), the brain modulates neuronal activity patterns, exploring and exploiting the state space defined by their neural manifold. Neurons directly involved in BMI control (i.e., direct neurons) can display marked changes in their firing patterns during BMI learning. However, the extent of firing pattern changes in neurons not directly involved in BMI control (i.e., indirect neurons) remains unclear. To clarify this issue, we localized direct and indirect neurons to separate hemispheres in a task designed to bilaterally engage these hemispheres while animals learned to control the position of a platform with their neural signals. Animals that learned to control the platform and improve their performance in the task shifted from a global strategy, where both direct and indirect neurons modified their firing patterns, to a local strategy, where only direct neurons modified their firing rate, as animals became expert in the task. Animals that did not learn the BMI task did not shift from utilizing a global to a local strategy. These results provide important insights into what differentiates successful and unsuccessful BMI learning and the computational mechanisms adopted by the neurons. [ABSTRACT FROM AUTHOR]

Purpose: The effects of the combination of strength training and acupuncture on chronic ankle instability have not been studied. This study examined effects of strength training combined with acupuncture on balance ability, ankle motion perception, and muscle strength in chronic ankle instability among college students. Methods: Forty-six chronic ankle instability college students were randomly categorized into the experimental group (n = 24, strength training + acupuncture) and the control group (n = 22, strength training) for an 8-week intervention. Results: For the results at 8 weeks, compared with the baseline, in the experimental group, the chronic Ankle Instability Tool (CAIT) score, ankle dorsiflexion, plantar flex, eversion peak torque (60°/s), and plantar flex peak torque (180°/s) increased by 13.7%, 39.4%, 13.7%, 14.2%, and 12.3%, respectively. Dorsiflexion, plantar flexion, inversion, and eversion kinesthetic sensation test angles decreased by 17.4%, 20.6%, 15.0%, and 17.2%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. Anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 28.9%, 31.6%, 33.3%, and 12.4%, respectively. In the control group, the Cumberland Ankle Instability Tool score and the ankle dorsiflexion peak torque (60°/s) increased by 13.8% and 17.9%, respectively. The inversion kinesthetic sensation test angle decreased by 15.2%, whereas anterior-posterior and medial-lateral displacement, and anterior-posterior and medial-lateral mean velocity decreased by 17.1%, 29.4%, 12.3%, and 16.8%, respectively. 2) For the comparison between the groups after 8 weeks, the values of ankle dorsiflexion and plantar flex peak torque (60°/s) in the experimental group were greater than those in the control group. The values of ankle plantar flex kinesthetic sensation test angle, the anterior-posterior displacement, and anterior-posterior mean velocity in the experimental group were lower than those in the control group. Conclusion: Acupuncture treatment in conjunction with muscle strength training can further improve the balance ability of anterior-posterior, ankle dorsiflexion, and plantar flex strength and plantar flex motion perception in chronic ankle instability participants. [ABSTRACT FROM AUTHOR]

The adaptability of hexapods for various locomotion tasks, especially in rescue and exploration missions, drives their application. Unlike controlled environments, these robots need to navigate ever-changing terrains, where ground irregularities impact foothold positions and origin shifts in contact forces. This dynamic interaction leads to varying hexapod postures, affecting overall system stability. This study introduces a posture control approach that adjusts the hexapod's main body orientation and height based on terrain topology. The strategy estimates ground slope using limb positions, thereby calculating novel limb trajectories to modify the hexapod's angular position. Adjusting the hexapod's height, based on the calculated slope, further enhances main body stability. The proposed methodology is implemented and evaluated on the ATHENA hexapod (All-Terrain Hexapod for Environment Adaptability). Control feasibility is assessed through dynamic analysis of the hexapod's multibody model on irregular surfaces, using computational simulations in Gazebo software. Environmental complexity's impact on hexapod stability is tested on both a ramp and uneven terrain. Independent analyses for each scenario evaluate the controller's effect on roll and pitch angular velocities, as well as height variations. Results demonstrate the strategy's suitability for both environments, significantly enhancing posture stability. [ABSTRACT FROM AUTHOR]

BACKGROUND: The restoration and management of the uninvolved side have been emphasized to prevent a second anterior cruciate ligament (ACL) injury and to ensure that athletes return to sports after ACL reconstruction. OBJECTIVE: To determine the factors influencing the single leg hop test (SLHT) and single leg vertical jump test (SLVJT) at 1 year postoperatively after ACL reconstruction in both the involved and uninvolved sides. METHODS: Ninety-four patients who underwent ACL reconstruction were assessed at 1 year postoperatively. Multiple regression models included eight independent variables with two dependent variables (SLHT and SLVJT.), each on the involved and uninvolved side. RESULTS: On the involved side, the Y balance test (YBT), extensor peak torque per body weight (PT/BW), Biodex balance system anteroposterior index (BBS-API), and sex accounted for 53.9% of the variance in SLHT (P = 0.002), and extensor PT/BW and YBT accounted for 26.3% of the variance in SLVJT (P = 0.027). On the uninvolved side, YBT, sex, age, BBS-API, and flexor PT/BW accounted for 47.0% of the variance in SLHT (P = 0.046), and flexor PT/BW, YBT, and age accounted for 44.9% of the variance in SLVJT (P = 0.002). CONCLUSION: Knee extensor strength on the involved side and flexor strength on the uninvolved side influence the two functional performance tests. The YBT was an important factor in the two functional performance tests in both sides. Anteroposterior stability was the only factor that influenced the SLHT bilaterally. [ABSTRACT FROM AUTHOR]

Chronic heart failure (CHF) is a complex clinical syndrome, associated with frailty, higher fall rates, and frequent hospitalizations. Heart Failure (HF) and preserved ejection fraction (HFpEF) is defined as a condition where a patient with HF have a diagnosis of left ventricular ejection fraction (LVEF) of ≥ 50%. The risk of HFpEF increases with age and is related to higher non-cardiovascular mortality. The aim of this study was to evaluate static balance and examine the effect of task difficulty on the discriminating power of balance control between patients with HFpEF (Patients with HFpEF) and their healthy controls. Moreover, the associations between static balance parameters, balance confidence, falls, lean muscle mass, and strength were assessed. Seventy two patients with HFpEF (mean age: 66.0 ± 11.6 years) and seventy two age- and gender-matched healthy individuals (mean age: 65.3 ± 9.5 years) participated in this study. Participants underwent a 30 s bilateral stance (BS) test and a 20 s Tandem-Romberg stance (TRS) on a force platform, evaluating the Range and Standard Deviation of Center of Pressure (COP) displacement parameters in both axes. Balance confidence was evaluated by the Activities-Specific Balance Confidence (ABC) Scale, and the number of falls during the last year was recorded. Lower limb strength was measured using an isokinetic dynamometer, isometric leg strength, and a Sit-to-Stand test. Bioelectrical impedance analysis was conducted to assess lean fat mass, lean fat mass index, and lean%. Patients with HFpEF presented with lower static balance in BS and TRS compared to healthy controls (p < 0.05), lower balance confidence by 21.5% (p < 0.05), and a higher incidence of falls by 72.9% (p < 0.05). BS was a better descriptor of the between-group difference. Furthermore, static balance, assessed in controlled lab conditions, was found to have little if no relationship to falls, strength, lean muscle mass, and balance confidence. Although no correlation was noted between the static balance parameters and falls, the fall rate was related to balance confidence, age, muscle strength, and lean fat.

Visual information affects static postural control, but how it affects dynamic postural control still needs to be fully understood. This study investigated the effect of proprioception weighting, influenced by the presence or absence of visual information, on dynamic posture control during voluntary trunk movements. We recorded trunk movement angle and angular velocity, center of pressure (COP), electromyographic, and electroencephalography signals from 35 healthy young adults performing a standing trunk flexion–extension task under two conditions (Vision and No-Vision). A random forest analysis identified the 10 most important variables for classifying the conditions, followed by a Wilcoxon signed-rank test. The results showed lower maximum forward COP displacement and trunk flexion angle, and faster maximum flexion angular velocity in the No-Vision condition. Additionally, the alpha/beta ratio of the POz during the switch phase was higher in the No-Vision condition. These findings suggest that visual deprivation affects cognitive- and sensory-integration-related brain regions during movement phases, indicating that sensory re-weighting due to visual deprivation impacts motor control. The effects of visual deprivation on motor control may be used for evaluation and therapeutic interventions in the future.

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Robotic arms with redundant degrees of freedom are known to exhibit characteristics that make them more suitable than their non-redundant counterparts in many manipulation tasks. These redundant degrees of freedom allow for multiple control objectives to be pursued simultaneously leading to increased efficiency, dexterity and versatility. Redundancy however brings about structural complexity, difficulties in tasks specification, challenging kinematics and dynamics and high computational cost. This work tackles kinematic hyper redundancy resolution in the context of posture (shape) control of a modular serial link arm by proposing a new take on formulating and solving the problem. In the proposed formulations, strategic points along the arm (termed control points) are explicitly controlled in such way that their overall motion steers the posture of the arm toward the desired target posture. These control points stem from the modular structure of the arm and are chosen in order to achieve specific control characteristics. Desired target posture outlines are specified intuitively and arbitrarily with continuous spline curves. The proposed method has demonstrated the ability to safely steer the arm towards intermediate postures which reduce the overall posture tracking error. It copes well with singularities and is capable of tracking target postures that are significantly distinct from the arm's initial posture. Numerical simulations on a 40 DOF arm are conducted to assess the validity and performance of the method. [ABSTRACT FROM AUTHOR]

When learning to use a brain-machine interface (BMI), the brain modulates neuronal activity patterns, exploring and exploiting the state space defined by their neural manifold. Neurons directly involved in BMI control (i.e., direct neurons) can display marked changes in their firing patterns during BMI learning. However, the extent of firing pattern changes in neurons not directly involved in BMI control (i.e., indirect neurons) remains unclear. To clarify this issue, we localized direct and indirect neurons to separate hemispheres in a task designed to bilaterally engage these hemispheres while animals learned to control the position of a platform with their neural signals. Animals that learned to control the platform and improve their performance in the task shifted from a global strategy, where both direct and indirect neurons modified their firing patterns, to a local strategy, where only direct neurons modified their firing rate, as animals became expert in the task. Animals that did not learn the BMI task did not shift from utilizing a global to a local strategy. These results provide important insights into what differentiates successful and unsuccessful BMI learning and the computational mechanisms adopted by the neurons.

Abstract Background The posture control deficit is one important dysfunction in adolescent idiopathic scoliosis (AIS) patients, which is related to the development of the disease. However, it is not apparent whether AIS could affect static sitting posture control in late adolescence. Objective This study aims to compare static sitting posture control in idiopathic scoliosis freshmen with normal peers to reveal possible differences in posture stability between them during writing tasks. Methods In total, there were 10 AIS patients and 11 normal college students chosen for the writing task test. Data on the distribution of gluteal pressure during sitting were gathered. The comparison between these two groups was made using the independent sample t-test. Results The total excursion (TE) of the center of pressure (COP) of the AIS group considerably increased in comparison with the control group (CON) (p = 0.029). The AIS group's average COP velocity in the anteroposterior (AP) direction was significantly higher than the CON group (p = 0.048). The peak gluteal pressure on the right side was significantly higher in the AIS group than in the CON group (p = 0.039). The right gluteal contact area dynamic variation was significantly higher in the AIS group compared to the CON group (p = 0.025). Conclusions AIS patients showed increased gluteal pressure and lower sitting posture stability during writing tasks.

In-pipe robots have become popular, allowing for non-destructive testing, visual inspection, and cleaning. In-pipe inspection is crucial for maintaining pipeline integrity, but it is difficult for humans to access pipelines and perform checks. This article focuses on an in-pipe robot navigating various pipeline structures and diameters. It consists of a center module, a tracking module, and an active pantograph mechanism. The hardware components, such as the motorized gear train, screw, pantograph mechanism, springs, track module, and angular sensors, are discussed. Additionally, the control methods employed by the robot, including normal force control and posture control, are explained. Finally, the tracking algorithms used to estimate the robot's position and direction within the pipeline are presented. [ABSTRACT FROM AUTHOR]

Background: The posture control deficit is one important dysfunction in adolescent idiopathic scoliosis (AIS) patients, which is related to the development of the disease. However, it is not apparent whether AIS could affect static sitting posture control in late adolescence. Objective: This study aims to compare static sitting posture control in idiopathic scoliosis freshmen with normal peers to reveal possible differences in posture stability between them during writing tasks. Methods: In total, there were 10 AIS patients and 11 normal college students chosen for the writing task test. Data on the distribution of gluteal pressure during sitting were gathered. The comparison between these two groups was made using the independent sample t-test. Results: The total excursion (TE) of the center of pressure (COP) of the AIS group considerably increased in comparison with the control group (CON) (p = 0.029). The AIS group's average COP velocity in the anteroposterior (AP) direction was significantly higher than the CON group (p = 0.048). The peak gluteal pressure on the right side was significantly higher in the AIS group than in the CON group (p = 0.039). The right gluteal contact area dynamic variation was significantly higher in the AIS group compared to the CON group (p = 0.025). Conclusions: AIS patients showed increased gluteal pressure and lower sitting posture stability during writing tasks. [ABSTRACT FROM AUTHOR]

summary: Purpose: Hemiparesis in stroke survivors has been reported to affect respiratory function. The relationship between trunk control and respiratory function, however, is not well understood. We aimed to map the state of the association between the trunk and respiratory function as well as evaluate the effect of a respiratory function training intervention on trunk control for stroke survivors. Methods: A scoping review and meta-analysis of observational and interventional studies were performed. Cochrane Library, CINAHL with Full Text (EBSCO), Medline (Ovid), and PubMed were searched using the terms stroke, respiratory, and trunk control. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist was used to examine the sections of each report. Results: A total of 102 studies were identified, of which 12, published between 2011 and 2022, were included in the meta-analysis or narrative synthesis. Three studies were included in the meta-analysis of the correlation between trunk control and respiratory function parameters (forced vital capacity [FVC], forced expiratory volume during the first breath [FEV1], maximal inspiratory pressure [MIP], and maximal expiratory pressure [MEP]) with effect sizes (Fisher's z) for all outcomes, which ranged from small to intermediate (between 0.21 and 0.39). Furthermore, five studies were included in the meta-analysis of the effect of respiratory function training intervention on trunk control. An overall effect size (Cohen's d) of 1.47 corresponds to a large effect. We also found significant improvements in MIP and MEP but not in FVC and FEV1 for stroke survivors with the interventions. Conclusions: Respiratory training, use of diaphragmatic resistance exercise or abdominal breathing, use of a pressure threshold-loading device, and the performance of functional strengthening exercises for the trunk muscles were found to increase patients’ trunk control and improve their respiratory muscle strength.

This paper describes the development of an in-pipe inspection robot system designed for large-diameter water pipes. The robot is equipped with a Magnetic Flux Leakage (MFL) sensor module. The robot system is intended for pipes with diameters ranging from 900 mm to 1200 mm. The structure of the in-pipe inspection robot consists of the front and rear driving parts, with the inspection module located centrally. The robot is powered by 22 motors, including eight wheels with motors positioned at both the bottom and the top for propulsion. To ensure that the robot’s center aligns with that of the pipeline during operation, lifting units have been incorporated. The robot is equipped with cameras and LiDAR sensors at the front and rear to monitor the internal environment of the pipeline. Pipeline inspection is conducted using the MFL inspection modules, and the robot’s driving mechanism is designed to execute spiral maneuvers while maintaining contact with the pipeline surface during rotation. The in-pipe inspection robot is configured with wireless communication modules and batteries, allowing for wireless operation. Following its development, the inspection robot underwent driving experiments in actual pipelines to validate its performance. The field test bed used for these experiments is approximately 1 km in length. Results from the driving experiments on the field test bed confirmed the robot’s ability to navigate various curvatures and obstacles within the pipeline. It is posited that the use of the developed in-pipe inspection robot can reduce economic costs and enhance the safety of inspectors when examining aging pipes.

ABSTRACT Objective: The analysis of the X-ray results of surgical treatment performed in patients with post-traumatic thoracolumbar kyphosis and identification of the compensatory mechanism for this deformity. Methods: The data of 140 patients surgically treated for painful post-traumatic kyphosis at the level of T12, L1, and L2 vertebrae was analyzed. Results: In the studied group, the initial kyphotic deformity was 23° to 81°, with a mean of 28.1°. All patients underwent staged surgical intervention in a single surgical session. Post-traumatic kyphosis (LK) was completely corrected, on average, to -0.25°. After kyphosis correction, increased thoracic kyphosis (TK) decreased lumbar lordosis (LL), including at the expense of low lumbar lordosis (LowLL), but no changes in pelvic balance parameters were observed. Statistically significant correlations of local kyphosis correction magnitude of 28.36±8.89°, with magnitudes of lumbar lordosis (LL), thoracic kyphosis (TK), low lumbar lordosis (LowLL) were obtained. The global sagittal and pelvic balance demonstrated no correlations with the magnitude of kyphosis correction. The X-ray parameters were studied in patients of Group I with no signs of initial sagittal imbalance and in Group II patients with signs of sagittal imbalance. The groups demonstrated statistically significant differences in global balance parameters and spinopelvic parameters both before and after correction surgery. Conclusion: The study revealed that the basic compensatory mechanism for post-traumatic thoracolumbar kyphosis is implemented by changes in the curves adjacent to kyphosis - a decrease in thoracic kyphosis and an increase in lumbar lordosis but not by changes in global or spinopelvic balance. Level of Evidence - III; A case-control study.

Older adults are benefited from the continuous tactile information to enhance postural control. Therefore, the aim was to evaluate the effect of the haptic anchors during balancing and walking tasks in older adults. The search strategy (up to January 2023) was based on the PICOT (older adults; anchor system during balance and walking tasks; any control group; postural control measurements; short and/or long-term effect). Two pairs of reviewers independently examined all titles and abstracts for eligibility. The reviewers independently extracted data from the included studies, assessed the risk of bias, and certainty of the evidence. Six studies were included in the qualitative synthesis. All studies used a 125-g haptic anchor system. Four studies used anchors when standing in a semi-tandem position, two in tandem walking on different surfaces, and one in an upright position after plantar flexor muscle fatigue. Two studies showed that the anchor system reduced body sway. One study showed that the ellipse area was significantly lower for the 50% group (reduced frequency) in the post-practice phase. One study showed that the reduction in the ellipse area was independent of the fatigue condition. Two studies observed reduced trunk acceleration in the frontal plane during tandem waking tasks. The studies had low to moderate certainty of evidence. Haptic anchors can reduce postural sway during balance and walking tasks in older adults. Also, positive effects were seen during the delayed post-practice phase after the removal of anchors only in individuals who used a reduced anchor frequency. [ABSTRACT FROM AUTHOR]

Accurate recognition of disabled persons' behavioral intentions is the key to reconstructing hand function. Their intentions can be understood to some extent by electromyography (EMG), electroencephalogram (EEG), and arm movements, but they are not reliable enough to be generally accepted. In this paper, characteristics of foot contact force signals are investigated, and a method of expressing grasping intentions based on hallux (big toe) touch sense is proposed. First, force signals acquisition methods and devices are investigated and designed. By analyzing characteristics of signals in different areas of the foot, the hallux is selected. The peak number and other characteristic parameters are used to characterize signals, which can significantly express grasping intentions. Second, considering complex and fine tasks of the assistive hand, a posture control method is proposed. Based on this, many human-in-the-loop experiments are conducted using human–computer interaction methods. The results showed that people with hand disabilities could accurately express their grasping intentions through their toes, and could accurately grasp objects of different sizes, shapes, and hardness using their feet. The accuracy of the action completion for single-handed and double-handed disabled individuals was 99% and 98%, respectively. This proves that the method of using toe tactile sensation for assisting disabled individuals in hand control can help them complete daily fine motor activities. The method is easily acceptable in terms of reliability, unobtrusiveness, and aesthetics. [ABSTRACT FROM AUTHOR]

Introduction: Patients with chronic low back pain (CLBP) exhibit changes in proprioceptive weighting and impaired postural control. This study aimed to investigate proprioceptive weighting changes in patients with CLBP and their influence on posture control. Methods: Sixteen patients with CLBP and 16 healthy controls were recruited. All participants completed the joint reposition test sense (JRS) and threshold to detect passive motion test (TTDPM). The absolute errors (AE) of the reposition and perception angles were recorded. Proprioceptive postural control was tested by applying vibrations to the triceps surae or lumbar paravertebral muscles while standing on a stable or unstable force plate. Sway length and sway velocity along the anteroposterior (AP) and mediolateral (ML) directions were assessed. Relative proprioceptive weighting (RPW) was used to evaluate the proprioception reweighting ability. Higher values indicated increased reliance on calf proprioception. Results: There was no significant difference in age, gender, and BMI between subjects with and without CLBP. The AE and motion perception angle in the CLBP group were significantly higher than those in the control group (JRS of 15°: 2.50 (2.50) vs. 1.50 (1.42), JRS of 35°: 3.83 (3.75) vs. 1.67 (2.00), pJRS < 0.01; 1.92 (1.18) vs. 0.68 (0.52), pTTDPM < 0.001). The CLBP group demonstrated a significantly higher RPW value than the healthy controls on an unstable surface (0.58 ± 0.21 vs. 0.41 ± 0.26, p < 0.05). Under the condition of triceps surae vibration, the sway length (pstable < 0.05; punstable < 0.001), AP velocity (pstable < 0.01; punstable < 0.001) and ML velocity (punstable < 0.05) had significant group main effects. Moreover, when the triceps surae vibrated under the unstable surface, the differences during vibration and post vibration in sway length and AP velocity between the groups were significantly higher in the CLBP group than in the healthy group (p < 0.05). However, under the condition of lumbar paravertebral muscle vibration, no significant group main effect was observed. Conclusion: The patients with CLBP exhibited impaired dynamic postural control in response to disturbances, potentially linked to changes in proprioceptive weighting. [ABSTRACT FROM AUTHOR]

Background and Aims: Balance is one of the important factors that help to maintain the independent life of people with intellectual disabilities. A variety of methods are used to assess balance in these individuals. However, so far no review study has been conducted to determine what kind of tests are used to assess balance in this group. Therefore, The purpose of this study was to investigate the methods of assessing postural control and balance used in studies on intellectual disabilities.Methods: In this study, a comprehensive search was performed on functional assessment tests of balance in people with intellectual disabilities. PubMed, Medline, Web of Science, ScienceDirect, Cochrane Central Register of Controlled Clinical Trials, Google Scholar, Scopus, Magiran, IranDoc, Iran Medex, MedLib, and SID were searched from 1991 to November 2020. After collecting the search results, first, the title and then the summary of the articles were studied. If the articles met the inclusion criteria, the results were used in the review study and otherwise discarded.Results: Based on the criteria and objectives of the research, 20 articles were selected after the evaluation process. All articles were provided in full text. Then, 23 Functional Balance Assessment Tests were used to measure functional balance in people with intellectual disabilities.Conclusion: Studies had examined the evaluation of functional balance in intellectual disabilities in several ways; therefore, it seems that a specific test cannot be suggested to measure the balance of intellectually disabled people.

Objective: The plantar pressure analysis technique was used to explore the static balance ability and stability of healthy adult males under the influence of visual and step height factors during bipedal and unipedal stances.Methods: Thirty healthy adult males volunteered for the study. Experiments used the F-scan plantar pressure analysis insoles to carry out with eyes open (EO) and eyes closed (EC) at four different step heights. The plantar pressure data were recorded for 10 s and pre-processed to derive kinematic and dynamic parameters.Results: For unipedal stance, most of kinematic parameters of the subjects’ right and left feet were significantly greater when the eyes were closed compared to the EO condition and increased with step height. The differences in toe load between right and left feet, open and closed eyes were extremely statistically significant (p < 0.001). The differences in midfoot load between the EO and EC conditions were statistically significant (p = 0.024) and extremely statistically significant between the right and left feet (p < 0.001). The difference in rearfoot load between EO and EC conditions was extremely statistically significant (p < 0.001) and statistically significant (p = 0.002) between the right and left feet. For bipedal stance, most of kinematic parameters of the subjects’ EO and EC conditions were statistically significant between the right and left feet and increased with step height. The overall load’s difference between EO and EC states was statistically significant (p = 0.003) for both feet. The overall load’s difference between the right and left feet was extremely statistically significant (p < 0.001) in the EC state. The differences between the right and left feet of the forefoot and rearfoot load with EO and EC suggested that the right foot had a smaller forefoot load, but a larger rearfoot load than the left foot (p < 0.001). The differences between the forefoot and rearfoot load of the subjects’ both feet with EO and EC were extremely statistically significant (p < 0.001).Conclusion: Both visual input and step height factors, even the dominant foot, act on kinematic and dynamic parameters that affect the maintenance of static balance ability.

For humans, control of upright standing posture is a prerequisite for many physical activities. Experimentally, this control is often challenged by the motion of the support surface presented as tilt or translation, or some combination thereof. In particular, we have investigated subjects balancing in situations where tilt and translation stimuli were presented in isolation and compared it to a situation where such stimuli occurred simultaneously. Is the human posture control system in the case of two or more superimposed external disturbances responding to these as if it were dealing with one disturbance? Or does it identify the disturbances individually and as such and respond to them specifically, as suggested in a current concept of disturbance-specific estimations and compensations? We had healthy human subjects controlling their balancing of upright stance on a motion platform while we presented them with different combinations of pseudorandom support surface tilt and translation stimuli alone or in superposition (with peak-to-peak amplitude of 0.5° and 1° for tilt, and 0.8 cm and 1.5 cm for translation). In one set of trials they kept their eyes closed and in a second set open. Furthermore, a simulation was performed to qualitatively evaluate the impact of sensory non-linearities and joint stiffness modulation. We found that the experimental conditions 'eyes open' vs. 'eyes closed' always created significant differences (p < 0.05) between the frequency response functions. In contrast to this, with different combinations of the tilt and translation stimuli, significant differences between the responses were observed only in 5 cases over the 24 that have been tested. Significance The superposition of translation and tilt can be used to characterize the responses to both stimuli with one trial. When the amplitude of the stimuli is unbalanced (e.g. very small tilt superimposed with a larger translation) the effect of stiffness modulation can be studied. • Upright stance tested with a superposition of support surface tilt and translation. • Steady state response is characterized by frequency response function. • Interaction between two stimuli absent in most of the cases. • Larger stimuli may create interaction. • Simulations suggest that the observed effects can be due to joint stiffness modulation. [ABSTRACT FROM AUTHOR]

Objectives: To observe the efficacy of botulinum toxin type A (BoNT-A) for the spasticity of the lower-limb post-stroke on gait and posture control. Methods: A total of 46 patients with hemiplegia gait were randomly divided into the experimental group (23 patients) and the control group (23 patients). In patients in the experimental group received injections of BoNT-A by electrical stimulation-guided. At the same time, patients of the two groups received routine physical therapy. Gait analysis, plantar pressure analysis, lower-limb Fugl-Meyer assessment (L-FMA), 10 meter walking test (10MWT), timed "Up and Go" test (TUGT), and modified Ashworth Scale assess (MAS) of the lower limbs were performed at 0, 1, 4, and 12 weeks after treatment. Results: At 1, 4, and 12 weeks after treatment, the L-FMA, stride length, speed, and TUGT significantly improved than 0 week in both groups. The L-FMA and peak of forefoot pressure, and MAS results in the experimental group were better than those in the control group at 4 and 12 weeks. The TUGT, speed, and stride length in experimental group was significantly shortened than that in control group at 1, 4, and 12 weeks. Conclusion: Botulinum toxin type A injection can improve motor functions of the lower limb, gait, spasticity, forefoot pressure, and posture control of patients after stroke. [ABSTRACT FROM AUTHOR]

Abstract Background Functional ankle instability (FAI) of college football players is an important risk factor affecting their training and competition. Physical therapy and appropriate sports intervention can improve the stability of FAI patients. Previous studies have shown that Tai Chi (TC) and Kinesio taping (KT) can improve the posture control ability of FAI patients. However, whether Tai Chi combined with Kinesio taping effect patch can be used as an effective exercise for rehabilitation of college football players with FAI is not yet proven. Methods/design Fifty-three FAI college football players were randomly assigned to 3 groups: TC+KT (n = 20); TC+KTp (placebo Kinesio taping, KTp, placebo) (n = 17), and KT (n = 16). The TC+KT group received TC and KT functional correction technical intervention, the TC+KTp group received TC and placebo KT technical intervention, and the KT group received KT functional correction technical intervention. Each of the three groups received 30 min each time, 3 times a week, for a total of 6 weeks of intervention training. Star Excursion Balance Test (SEBT) and UniPedal Stance Test (UST) at baseline (before), 4 weeks after intervention (middle), and 6 weeks after intervention (after) and Toe Touch Test (TTT) were evaluated. Discussion For the first time in this trial, the impact will be evaluated. If the results are the same as expected, they will provide evidence that Tai Chi combined with Kinesio taping sticking intervention can promote the posture control of college football players with FAI. Trial registration Chinese Clinical Trial Registry ChiCTR1900027253 . Registered on 6 November 2019.

The central nervous system (CNS) dynamically employs a sophisticated weighting strategy of sensory input, including vision, vestibular and proprioception signals, towards attaining optimal postural control during different conditions. Non-specific low back pain (NSLBP) patients frequently demonstrate postural control deficiencies which are generally attributed to challenges in proprioceptive reweighting, where they often rely on an ankle strategy regardless of postural conditions. Such impairment could lead to potential loss of balance, increased risk of falling, and Low back pain recurrence. In this study, linear and non-linear indicators were extracted from center-of-pressure (COP) and trunk sagittal angle data based on 4 conditions of vibration positioning (vibration on the back, ankle, none or both), 2 surface conditions (foam or rigid), and 2 different groups (healthy and non-specific low back pain patients). Linear discriminant analysis (LDA) was performed on linear and non-linear indicators to identify the best sensory condition towards accurate distinction of non-specific low back pain patients from healthy controls. Two indicators: Phase Plane Portrait ML and Entropy ML with foam surface condition and both ankle and back vibration on, were able to completely differentiate the non-specific low back pain groups. The proposed methodology can help clinicians quantitatively assess the sensory status of non-specific low back pain patients at the initial phase of diagnosis and throughout treatment. Although the results demonstrated the potential effectiveness of our approach in Low back pain patient distinction, a larger and more diverse population is required for comprehensive validation.

Reaching movements of the arms are accompanied by anticipatory (APM) and compensatory postural motion (CPM) that counteract the resulting perturbations to body stability. Recent research has shown that these postural actions are also observable in the context of imagined arm movements. As motor imagery (MI) shares many neurophysiological and behavioral characteristics with physical movements, and MI training can affect subsequent performance, MI tasks provide a good setting for studying the anticipatory aspects of postural control. This study investigated APMs and CPMs of the head and hip of healthy young and older adults in the temporal vicinity of physical and imagined forward raises of the dominant and non-dominant arm. When MI of the dominant arm was self-initiated, both age groups showed APM in the anteroposterior plane. When the self-initiated MI was of the non-dominant arm, only the older group showed anteroposterior APM. The older group did not show APM when an expected arm movement (or MI) was made to an external signal. This suggests an age-related deficit in coordinating postural preparation with external events. Only the older group showed mediolateral APM, and only for dominant arm MI, indicating sensitivity to potential perturbation to the weaker, non-dominant side of the body. Overall, the older group showed more anticipatory postural motion at the head. Systematic APM for manual MI suggests that MI training may be an effective intervention for anticipatory postural control. An integrated model of postural support for executed and imagined limb movements is suggested. [ABSTRACT FROM AUTHOR]

In this study, we developed an evaluation method using image analysis for reaching tasks. Using this method, we studied forearm function during the reaching task in rats that received a unilateral injection of 6-OHDA into the striatum. The success ratio of the reaching task reduced to 40.5% seven days after the injection. In addition, significant changes were observed in the pronation angle of the forearm, posture control, and targeting (i.e., the distance between all fingertips and the center of the target pellet). Thus, unilateral injection of 6-OHDA reduces dopaminergic function in the brain and causes deterioration of forearm function and posture control in the reaching task. [ABSTRACT FROM AUTHOR]

Background: Hypertension (HT) is a common chronic disease in older adults. It not only leads to dizziness and other symptoms affecting balance in older adults with HT but also affects the hemodynamics of the cerebral cortex. At present, potential neural mechanisms of balance control in older adults with HT are still unclear. Therefore, this study aimed to explore the differences in the center of pressure (COP) and cerebral cortex activation between older adults with HT and normotension (NT) during standing balance tasks. This study May provide guidance for the early detection of the risk of falls among older adults with HT and the development of clinical rehabilitation strategies., Methods: In this cross-sectional study, 30 older adults with NT (NT group) and 27 older adults with HT (HT group) were subjected to three conditions: task 1, standing with eyes open on a stable surface; task 2, standing with eyes closed on a stable surface; and task 3, standing with eyes open on the surface of the foam pad. Cortical hemodynamic reactions were measured using functional near-infrared spectroscopy, and COP parameters were measured using a force plate., Results: The mean velocity of the COP in the medial-lateral direction in the NT group was significantly higher than that in the HT group ( F  = 5.955, p  = 0.018) during task 3. When proprioception was disturbed, the activation of the left premotor cortex and supplementary motor cortex in the HT group was significantly lower than that in the NT group ( F  = 14.381, p  < 0.001)., Conclusion: The standing balance function of older adults with HT does not appear to be worse based on COP parameters than those of older adults with NT. This study revealed that the changes in the central cortex related to standing balance appear to be more indicative of balance control deficits in older adults with HT than changes in peripheral COP parameters, suggesting the importance of the early evaluation of cortical activation in older adults with HT at risk of falls., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Fan, Zeng, Zheng, Wen, Li, Fan, Huang, Zheng and Luo.)

Abstract Background Sit-to-stand (STS) is a complex movement that requires successful postural control. Aging is a normal part of human life that leads to weakness of sensory capabilities, resulting in diminished postural control. Therefore, STS movement is a challenging task for the elderly. Local tendon vibration (LTV) can be utilized to assist STS of the elderly by improving postural control. Many studies have revealed that the LTV has various physiological positive effect. However, previous studies did not consider subjects’ individual difference for properties of applied LTV. Also, there are almost no studies to assist and to improve elder’s STS movement. Thus, the purpose of this study was to examine the influence of lower limb LTV on postural sway during STS in the elderly, and to examine whether a specific vibration frequency can increase postural control in the elderly. Results The common characteristic differences between the elderly and younger population during STS movement were analyzed. In addition, the effect of vibration on the center of mass (COM) and the center of pressure (COP) variable responses in young adults and the elderly were investigated. As a result, the elderly exhibit larger COP sway area and higher COP mediolateral (ML) displacement than the young adults. In addition, the elderly generally have lower COM velocities in all directions compared to the young adults. It was found that COP and COM related to postural stability are affected when LTV of the 180 Hz, 190 Hz and 250 Hz is applied to the elderly. Particularly, the 190 Hz vibration induced significant reduction in COP sway area and COP ML displacement. Conclusions These results mean that the LTV contributes to stability of elders’ STS movement by reducing postural sway. Furthermore, a reduction of postural sway depends on frequency of the LTV. These findings suggest that individual response to characteristics of vibration must be considered, and imply that the LTV can be used as rehabilitation therapy to improve postural control in the elderly, and utilized in motion assistive devices to deliver apt vibration frequencies. Trial registration CRIS, KCT0005434 , Registered 25 September 2020, Retrospectively registered, https://cris.nih.go.kr/cris/index/index.do

Accurate recognition of disabled persons’ behavioral intentions is the key to reconstructing hand function. Their intentions can be understood to some extent by electromyography (EMG), electroencephalogram (EEG), and arm movements, but they are not reliable enough to be generally accepted. In this paper, characteristics of foot contact force signals are investigated, and a method of expressing grasping intentions based on hallux (big toe) touch sense is proposed. First, force signals acquisition methods and devices are investigated and designed. By analyzing characteristics of signals in different areas of the foot, the hallux is selected. The peak number and other characteristic parameters are used to characterize signals, which can significantly express grasping intentions. Second, considering complex and fine tasks of the assistive hand, a posture control method is proposed. Based on this, many human-in-the-loop experiments are conducted using human–computer interaction methods. The results showed that people with hand disabilities could accurately express their grasping intentions through their toes, and could accurately grasp objects of different sizes, shapes, and hardness using their feet. The accuracy of the action completion for single-handed and double-handed disabled individuals was 99% and 98%, respectively. This proves that the method of using toe tactile sensation for assisting disabled individuals in hand control can help them complete daily fine motor activities. The method is easily acceptable in terms of reliability, unobtrusiveness, and aesthetics.

Young adults reduce their sway in both light touch (LT) and anchor systems (AS), however, the cognitive involvement in these tasks is unknown. This study investigated postural control in young adults standing upright using either LT or AS, concomitantly with a cognitive task (counting). Nine adults (26 ± 7.4 years) stood in the upright tandem stance with eyes closed, with/without LT, AS (force <2 N), and a cognitive task. The mean sway amplitude of the trunk, right wrist, and shoulder ellipse area, as well as the mean force during LT and AS were obtained. The cognitive task did not influence the magnitude of trunk sway or the mean force in the LT and AS conditions. The trunk sway magnitude was reduced in the AS and even further in LT. Wrist and shoulder variability was larger in the AS than in the LT. Based on these results, we conclude that enhanced sensory cues provided by LT and AS reduce trunk sway with little or no attentional demands. [ABSTRACT FROM AUTHOR]

The integrated electric wheel module (IEWM) with large-angle steering capability is blooming which greatly alters the conventional chassis structure over recent years. The IEWM brings challenges to the suspension system due to higher requirements, which includes 360 degrees steering, active adjustment of chassis height and posture, superior ride comfort, and compact mechanical structure. Hence, a novel double trailing arm suspension mechanical system for the aforementioned IEWM and its control strategy are studied to get better driving maneuverability, ride comfort, driving safety, and posture stability of automobiles in this paper. The 6 degree of freedom (DOF) roll model of active suspension vibration with seats and multi-objective optimization controller are constructed for vehicle posture active control to solve the difficult trade-off between suspension dynamic deflection, roll angle, and seat vertical acceleration. The controller weight coefficients are optimized by an improved genetic algorithm (IGA) method, and the fitness function in piecewise form is adopted to reduce the search range. The simulation analysis shows that the combination of IGA and a multi-objective controller can defuse the conflict of goals between different suspension performance evaluation indexes, which also improves the overall suspension performances compared with the experience adjustment method and passive suspension system. In detail, this simple optimization control strategy can reduce the vertical acceleration root mean square value (RMSV) of the left and right seat by 45 % and 11 %, respectively; the left and right tire dynamic load decreased by 13 % and 2 %, respectively; and 25 % reduction in roll angle. These performance improvements only sacrifice part of suspension dynamic deflection RMSV increase, but do not affect driving safety. [ABSTRACT FROM AUTHOR]

This review is the second part of the critical analysis of recent papers of Russian and other authors devoted to the study of the stabilometric parameters in postural control biofeedback training and rehabilitation, associated with psychological functions. The review presents the studies of postural control features in chronic pain syndrome, chronic fatigue syndrome, Parkinson's disease, multiple sclerosis, and depression. The leading role of Russian researchers in the development and application of stabilometric biofeedback in the training of optimal functioning, rehabilitation, and correction of neurological disorders is noted. The paradigm of stabilometric biofeedback training of the cognitive and affective functions is offered. [ABSTRACT FROM AUTHOR]

The cerebellum is a significant motor regulation center under the cerebral cortex. It has strong anatomical and functional connections with different cortical regions of the brain, cooperating with the cerebral cortex to complete the motor function and motor learning of the body. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique. tDCS over the cerebellum can promote corticospinal excitability and modulate the functional connection between the cerebellum and the cerebral cortex through a weak electrical current. Two decades of domestic and foreign literature were collected and systematically reviewed the effects of tDCS over cerebellum in motor performance. Some studies showed that tDCS over the cerebellum can improve posture control, motor adaptation, motor learning and muscle strength performance. However, further research would be explored the physiological mechanism and stimulation intensity, stimulation time, stimulation interval time of tDCS over the cerebellum. In the field of sports science, further research would also be explored on how to apply cerebellar tDCS technique in sports training to help athletes break through the current athletic ability. [ABSTRACT FROM AUTHOR]

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Background: A range of cognitive tasks can interfere with postural control, particularly in older adults. In the case of spatial tasks, the spatial alignment between the task and postural control can incur dual-task costs separately from task load. It has been suggested that spatial tasks incur dual-task costs because accessing the visuospatial sketchpad component of working memory reduces the capacity to utilize external visual information for postural control.Research Question: We investigated whether the spatial alignment between a cognitive and a postural control task can affect postural stability even when visual perception is not involved in either task and task load does not differ between aligned and non-aligned conditions. We predicted that any such effect would be greater in older people and in a more challenging stance.Methods: Fifty healthy adults (27 aged 20-35, 23 aged 59-88) with no history of balance or cognitive difficulties performed a mental navigation task while standing in open or closed stance with eyes closed. The mental navigation task was presented in a reference plane that was either aligned or non-aligned to the horizontal reference plane in which the posture control system controlled the position of the body's center of gravity. Task performance was measured as accuracy and response time and postural sway as anteroposterior (AP) and mediolateral (ML) sway velocity.Results: The older group were less accurate in the mental navigation task, and both groups had higher AP and ML sway velocity in closed stance. When standing in the more challenging stance, the older group had higher AP sway velocity while performing the mental navigation task in the non-aligned than the aligned reference plane condition.Significance: The spatial configuration compatibility between a cognitive task and postural control can affect postural stability even when visual information is not being used for either task and task load is unchanged. [ABSTRACT FROM AUTHOR]