Full-body motion-based game interaction for older adults

Older adults in nursing homes often lead sedentary lifestyles, which reduces their life expectancy. Full-body motion-control games provide an opportunity for these adults to remain active and engaged; these games are not designed with age-related impairments in mind, which prevents the games from being leveraged to increase the activity levels of older adults. In this paper, we present two studies aimed at developing game design guidelines for full-body motion controls for older adults experiencing age-related changes and impairments. Our studies also demonstrate how full-body motion-control games can accommodate a variety of user abilities, have a positive effect on mood and, by extension, the emotional well-being of older adults. Based on our studies, we present seven guidelines for the design of full-body interaction in games. The guidelines are designed to foster safe physical activity among older adults, thereby increasing their quality of life. Copyright 2012 ACM

Feedback Control of an Exoskeleton for Paraplegics: Toward Robustly Stable Hands-free Dynamic Walking

This manuscript presents control of a high-DOF fully actuated lower-limb exoskeleton for paraplegic individuals. The key novelty is the ability for the user to walk without the use of crutches or other external means of stabilization. We harness the power of modern optimization techniques and supervised machine learning to develop a smooth feedback control policy that provides robust velocity regulation and perturbation rejection. Preliminary evaluation of the stability and robustness of the proposed approach is demonstrated through the Gazebo simulation environment. In addition, preliminary experimental results with (complete) paraplegic individuals are included for the previous version of the controller.Comment: Submitted to IEEE Control System Magazine. This version addresses reviewers' concerns about the robustness of the algorithm and the motivation for using such exoskeleton

Personal Mobility With Synchronous Trunk-Knee Passive Exoskeleton: Optimizing Human-Robot Energy Transfer

We present a personal mobility device for lower-body impaired users through a light-weighted exoskeleton on wheels. On its core, a novel passive exoskeleton provides postural transition leveraging natural body postures with support to the trunk on sit-to-stand and stand-to-sit (STS) transitions by a single gas spring as an energy storage unit. We propose a direction-dependent coupling of knees and hip joints through a double-pulley wire system, transferring energy from the torso motion towards balancing the moment load at the knee joint actuator. Herewith, the exoskeleton maximizes energy transfer and the naturalness of the user's movement. We introduce an embodied user interface for hands-free navigation through a torso pressure sensing with minimal trunk rotations, resulting on average $19^{\circ} \pm 13^{\circ}$ on six unimpaired users. We evaluated the design for STS assistance on 11 unimpaired users observing motions and muscle activity during the transitions. Results comparing assisted and unassisted STS transitions validated a significant reduction (up to $68\%$ $p<0.01$) at the involved muscle groups. Moreover, we showed it feasible through natural torso leaning movements of $+12^{\circ}\pm 6.5^{\circ}$ and $- 13.7^{\circ} \pm 6.1^{\circ}$ for standing and sitting, respectively. Passive postural transition assistance warrants further work on increasing its applicability and broadening the user population.Comment: IEEE/ASME Transactions on Mechatronics. 2022. 11 pages. doi: 10.1109/TMECH.2021.313545

A reconfigurable wheelchair for mobility and rehabilitation:Design and development

This paper presents the design and development of a prototype of a reconfigurable wheelchair for rehabilitation and self-assistance to fit the size of a seven years old child (average 35 kg weight). Though the developed prototype is developed at this stage to fit a child, it can be resized, after considering variations in weight and size, to fit an older adult. The developed prototype has a mechanism that enables the user to transform from sit-to-stand (STS) posture and vice versa. With the help of the developed wheelchair, the user will also be able to adjust the posture of his upper body using an adjustable back support using two linear actuators. This configuration will allow the user to use the wheelchair as a mobility device as well as for rehabilitation purposes without the need of external support. The availability of STS and back adjustment mechanisms will allow the user to do regular exercising which will enhance blood circulation as sitting for long periods inflates lower limbs disability. The proposed configuration will help in enhancing the functional capabilities of end-users allowing for increased independence and ultimately quality of life

Standing Assistance That Considers User Posture Tolerance

This paper proposes a novel standing assistance robot, which considers the posture tolerance of its user. In previous studies, conventional assistive robots did not require patients to use their own physical strength to stand, which leads to decreased strength in the elderly. Therefore, an assistive robot that allows patients to maximally use the physical strength they possess is required. To realize this objective, it is important that a robot assists patients according to their body movement and by their intentions. However, in previous studies, general assistive robots helped patients by using a xed motion reference path- way in spite of their original intention, and as a result, these robots failed to use the physical strength of the patients. Therefore, we propose a novel standing assistance robot, which allows its user to move their body within a prescribed degree of posture tolerance during the process of moving from a sitting to a standing position. Our key ndings cover two fundamental research topics. One is the investigation into posture tolerance during a standing motion. The other topic is a novel assistance control algorithm that considers the investigated posture tolerance by combining position control and force control. A prototype assistive robot, based on the proposed idea was fabricated to help patients stand up safely using the maximum of their remaining physical strength

Experience of Robotic Exoskeleton Use at Four Spinal Cord Injury Model Systems Centers

Background and Purpose: Refinement of robotic exoskeletons for overground walking is progressing rapidly. We describe clinicians\u27 experiences, evaluations, and training strategies using robotic exoskeletons in spinal cord injury rehabilitation and wellness settings and describe clinicians\u27 perceptions of exoskeleton benefits and risks and developments that would enhance utility. Methods: We convened focus groups at 4 spinal cord injury model system centers. A court reporter took verbatim notes and provided a transcript. Research staff used a thematic coding approach to summarize discussions. Results: Thirty clinicians participated in focus groups. They reported using exoskeletons primarily in outpatient and wellness settings; 1 center used exoskeletons during inpatient rehabilitation. A typical episode of outpatient exoskeleton therapy comprises 20 to 30 sessions and at least 2 staff members are involved in each session. Treatment focuses on standing, stepping, and gait training; therapists measure progress with standardized assessments. Beyond improved gait, participants attributed physiological, psychological, and social benefits to exoskeleton use. Potential risks included falls, skin irritation, and disappointed expectations. Participants identified enhancements that would be of value including greater durability and adjustability, lighter weight, 1-hand controls, ability to navigate stairs and uneven surfaces, and ability to balance without upper extremity support. Discussion and Conclusions: Each spinal cord injury model system center had shared and distinct practices in terms of how it integrates robotic exoskeletons into physical therapy services. There is currently little evidence to guide integration of exoskeletons into rehabilitation therapy services and a pressing need to generate evidence to guide practice and to inform patients\u27 expectations as more devices enter the market. Background and Purpose: Refinement of robotic exoskeletons for overground walking is progressing rapidly. We describe clinicians\u27 experiences, evaluations, and training strategies using robotic exoskeletons in spinal cord injury rehabilitation and wellness settings and describe clinicians\u27 perceptions of exoskeleton benefits and risks and developments that would enhance utility. Methods: We convened focus groups at 4 spinal cord injury model system centers. A court reporter took verbatim notes and provided a transcript. Research staff used a thematic coding approach to summarize discussions. Results: Thirty clinicians participated in focus groups. They reported using exoskeletons primarily in outpatient and wellness settings; 1 center used exoskeletons during inpatient rehabilitation. A typical episode of outpatient exoskeleton therapy comprises 20 to 30 sessions and at least 2 staff members are involved in each session. Treatment focuses on standing, stepping, and gait training; therapists measure progress with standardized assessments. Beyond improved gait, participants attributed physiological, psychological, and social benefits to exoskeleton use. Potential risks included falls, skin irritation, and disappointed expectations. Participants identified enhancements that would be of value including greater durability and adjustability, lighter weight, 1-hand controls, ability to navigate stairs and uneven surfaces, and ability to balance without upper extremity support. Discussion and Conclusions: Each spinal cord injury model system center had shared and distinct practices in terms of how it integrates robotic exoskeletons into physical therapy services. There is currently little evidence to guide integration of exoskeletons into rehabilitation therapy services and a pressing need to generate evidence to guide practice and to inform patients\u27 expectations as more devices enter the market

Master of Science

thesisManual Material Handing (MMH) is a common activity for many workers in the workplace. Back compressive force has been described as a leading factor causing back injuries and musculoskeletal disorders (MSD) associated with lifting. To prevent such injuries, mechanical Lift Assist Devices (LAD) have been developed. To improve device usability and allow more interaction with human body movements, a significant step has been taken towards developing an automatic feedback control system for a hybrid lift assist device. The control system is highly responsive which would likely result in a reduction of required erector spine muscle force during lifting tasks. The control system is based on multiple input and multiple output (MIMO).This design was chosen to control the outputs of Torque (τ) and Speed (ω) generated from a DC motor from the inputs: hip angle, torso angle and HD (Horizontal Distance from L5/S1 to center of load derived from the Force and Center of Pressure (COP) using Flexi Force Sensors in the shoe insole). All the inputs were derived and compared with parameters of human body movement recorded using Vicon Nexus and 8 Bonita cameras. The Utah Back Compressive model was used to estimate the desired torque required by the LAD. The motor is controlled to generate the amount of torque to lift the load and to assist the body to a specified percent assist (0-100%). The design of the control system was achieved using a proper controller and DC motor with a closed loop feedback system. The control system produces reliable and robust performance for a variety of sagittal plane lifting techniques. This was accomplished by deriving the system input parameters from measurable device features and fine tuning the controller and selected DC motor model. These results indicate that a hybrid lifting assist device is feasible and can be programmed to provide variable assistance during lifting tasks

Universal Design: Planning and Design for All

[Excerpt] This report attempts to develop and illustrate the concept of universal design. The aim of universal design is to develop theory, principles and solutions to enable everybody to use the same physical solutions to the greatest extent possible, whether it be buildings, outdoor-areas, means of communication or household goods. Universal design opposes, ideologically and politically, all unnecessary and stigmatizing specialized solutions, whether they are intended for people with disabilities or other groups of the population. Equal status, equal treatment and equal merit are key concepts. The discussion in this report covers extensive spheres such as planning, architecture and product design. One may object that we try to cover too large an area within a relatively brief report. It is therefore important to emphasise that our main intention is to include more professionals and politicians in the further discussion of universal design or design for all

Trunk Rehabilitation Using Cable-Driven Robotic Systems

Upper body control is required to complete many daily tasks. One needs to stabilize the head and trunk over the pelvis, as one shifts the center of mass to interact with the world. While healthy individuals can perform activities that require leaning, reaching, and grasping readily, those with neurological and musculoskeletal disorders present with control deficits. These deficits can lead to difficulty in shifting the body center of mass away from the stable midline, leading to functional limitations and a decline in the quality of activity. Often these patient groups use canes, walkers, and wheelchairs for support, leading to occasional strapping or joint locking of the body for trunk stabilization. Current rehabilitation strategies focus on isolated components of stability. This includes strengthening, isometric exercises, hand-eye coordination tasks, isolated movement, and proprioceptive training. Although all these components are evidence based and directly correlate to better stability, motor learning theories such as those by Nikolai Bernstein, suggest that task and context specific training can lead to better outcomes. In specific, based on our experimentation, we believe functional postural exploration, while encompassing aspects of strengthening, hand-eye coordination, and proprioceptive feedback can provide better results. In this work, we present two novel cable robotic platforms for seated and standing posture training. The Trunk Support Trainer (TruST) is a platform for seated posture rehabilitation that provides controlled external wrench on the human trunk in any direction in real-time. The Stand Trainer is a platform for standing posture rehabilitation that can control the trunk, pelvis, and knees, simultaneously. The system works through the use of novel force-field algorithms that are modular and user-specific. The control uses an assist-as-needed strategy to apply forces on the user during regions of postural instability. The device also allows perturbations for postural reactive training. We have conducted several studies using healthy adult populations and pilot studies on patient groups including cerebral palsy, cerebellar ataxia, and spinal cord injury. We propose new training methods that incorporate motor learning theory and objective interventions for improving posture control. We identify novel methods to characterize posture in form of the “8-point star test”. This is to assess the postural workspace. We also demonstrate novel methods for functional training of posture and balance. Our results show that training with our robotic platforms can change the trunk kinematics. Specifically, healthy adults are able to translate the trunk further and rotate the trunk more anteriorly in the seated position. In the standing position, they can alter their reach strategy to maintain the upper trunk more vertically while reaching. Similarly, Cerebral Palsy patients improve their trunk translations, reaching workspace, and maintain a more vertical posture after training, in the seated position. Our results also showed that an Ataxia patient was able to improve their reaching workspace and trunk translations in the standing position. Finally, our results show that the robotic platforms can successfully reduce trunk and pelvis sway in spinal cord injury patients. The results of the pilot studies suggest that training with our robotic platforms and methods is beneficial in improving trunk control

Isometric push/pull strength of agricultural workers of Central India

Many manually operated farm tools and equipment require exertion of push/pull force in horizontal plane. However, very few data are available on push/pull strength of agricultural workers of India. &nbsp;A study was therefore, carried out to collect these data on male as well as female agricultural workers in the state of Madhya Pradesh, India. &nbsp;A strength measurement set-up developed at CIAE, Bhopal was used for the purpose. &nbsp;The data were collected on 1701 agricultural workers as subjects from 20 selected districts representing various agro-climatic zones of Madhya Pradesh out of which 944 were male and 757 were female. &nbsp;The mean age, stature and mass of the male subjects were (29.8&plusmn;9.5) years, (1649&plusmn;59) mm and (51.2&plusmn;6.4) kg whereas for female subjects the values were (33.7&plusmn;8.2) years, (1519&plusmn;54) mm and (45.0&plusmn;7.3) kg, respectively. &nbsp;The isometric push/pull strength of male subjects was higher than those of female subjects. The mean values for isometric push and pull strength in standing posture with both hands (in horizontal plane) were (242.4&plusmn;56.4) N and (231.0&plusmn;42.5) N, respectively for male workers and (175.5&plusmn;33.9) N and (159.4&plusmn;42.9) N, respectively for female workers. &nbsp;The mass of the subjects indicated a positive correlation with isometric push/pull strength. &nbsp;The 5th percentile push and pull strength values were &nbsp;149.7 N and 161.2 N for male workers and 119.7 N and 88.8 N for female workers. &nbsp;These values can be used to set a limit in the design of manually operated farm tools and equipment as well as for manual materials handling activities involving push/pull forces depending on the frequency of movement. &nbsp;Considering the ergonomical requirement of 30% of the 5th percentile strength for frequent exertions, the design limits of push and pull strengths for male workers will be 45 N and 48 N and for female it will be 36 N and 27 N. &nbsp;For the occasional exertions, the limit of push and pull strength is 60% of the strength which will be 90 N to 96 N for male and 72 N to 54 N for female workers.Keywords: push/pull strength, agricultural workers, central India, agricultural machinery&nbsp;Citation: Agrawal K. N., P. S. Tiwari, L. P. Gite, and V. Bhushanababu.&nbsp; Isometric push/pull strength of agricultural workers of Central India. &nbsp;Agric Eng Int: CIGR Journal, 2010, 12(1): 115-124.&nbsp;&nbsp