Repetitive overhead tasks during factory work can cause shoulder injuries resulting in impaired health and productivity loss. Soft wearable upper extremity robots have the potential to be effective injury prevention tools with minimal restrictions using soft materials and active controls. We present the design and evaluation of a portable inflatable shoulder wearable robot for assisting industrial workers during shoulder-elevated tasks. The robot is worn like a shirt with integrated textile pneumatic actuators, inertial measurement units, and a portable actuation unit. It can provide up to 6.6 newton-meters of torque to support the shoulder and cycle assistance on and off at six times per minute. From human participant evaluations during simulated industrial tasks, the robot reduced agonist muscle activities (anterior, middle, and posterior deltoids and biceps brachii) by up to 40% with slight changes in joint angles of less than 7% range of motion while not increasing antagonistic muscle activity (latissimus dorsi) in current sample size. Comparison of controller parameters further highlighted that higher assistance magnitude and earlier assistance timing resulted in statistically significant muscle activity reductions. During a task circuit with dynamic transitions among the tasks, the kinematics-based controller of the robot showed robustness to misinflations (96% true negative rate and 91% true positive rate), indicating minimal disturbances to the user when assistance was not required. A preliminary evaluation of a pressure modulation profile also highlighted a trade-off between user perception and hardware demands. Finally, five automotive factory workers used the robot in a pilot manufacturing area and provided feedback.

Chronic impairment in the paretic ankle following stroke often requires that individuals use compensatory patterns such as asymmetric propulsion to achieve effective walking speeds needed for community engagement. Ankle exosuit assistance can provide ankle biomechanical benefit in the lab, but such environments inherently limit the amount of practice available. Community walking studies without exosuits can provide massed practice and benefit walking speed but are limited in their ability to assist proper mechanics. In this study, we combined the positive aspects of community training with those of exosuit assistance. We developed and evaluated a community Robotic Exosuit Augmented Locomotion (cREAL) program. Four participants in the chronic stage of stroke independently used our community ankle exosuit for walking in the community 3-5 days/week for 4 weeks. We performed lab evaluations before and after the 4-week program. Two participants significantly improved their unassisted paretic propulsion by an average of 27% after the program and walked on average 4001 steps/day more in the week following the program. Despite the small number of participants, this study provides preliminary evidence for the potential of exosuits to augment gait training and rehabilitation in the community.

Chronic impairment in the paretic ankle following stroke often requires that individuals use compensatory patterns such as asymmetric propulsion to achieve effective walking speeds needed for community engagement. Ankle exosuit assistance can provide ankle biomechanical benefit in the lab, but such environments inherently limit the amount of practice available. Community walking studies without exosuits can provide massed practice and benefit walking speed but are limited in their ability to assist proper mechanics. In this study, we combined the positive aspects of community training with those of exosuit assistance. We developed and evaluated a community Robotic Exosuit Augmented Locomotion (cREAL) program. Four participants in the chronic stage of stroke independently used our community ankle exosuit for walking in the community 3–5 days/week for 4 weeks. We performed lab evaluations before and after the 4-week program. Two participants significantly improved their unassisted paretic propulsion by an average of 27% after the program and walked on average 4001 steps/day more in the week following the program. Despite the small number of participants, this study provides preliminary evidence for the potential of exosuits to augment gait training and rehabilitation in the community.

As we age, humans see natural decreases in muscle force and power which leads to a slower, less efficient gait. Improving mobility for both healthy individuals and those with muscle impairments/weakness has been a goal for exoskeleton designers for decades. In this work, we discover that significant reductions in the energy cost required for walking can be achieved with almost 50% less mechanical power compared to the state of the art. This was achieved by leveraging human-in-the-loop optimization to understand the importance of individualized assistance for hip flexion, a relatively unexplored joint motion. Specifically, we show that a tethered hip flexion exosuit can reduce the metabolic rate of walking by up to 15.2 ± 2.6%, compared to locomotion with assistance turned off (equivalent to 14.8% reduction compared to not wearing the exosuit). This large metabolic reduction was achieved with surprisingly low assistance magnitudes (average of 89 N, ~ 24% of normal hip flexion torque). Furthermore, the ratio of metabolic reduction to the positive exosuit power delivered was 1.8 times higher than ratios previously found for hip extension and ankle plantarflexion. These findings motivated the design of a lightweight (2.31 kg) and portable hip flexion assisting exosuit, that demonstrated a 7.2 ± 2.9% metabolic reduction compared to walking without the exosuit. The high ratio of metabolic reduction to exosuit power measured in this study supports previous simulation findings and provides compelling evidence that hip flexion may be an efficient joint motion to target when considering how to create practical and lightweight wearable robots to support improved mobility.

Walking and running have fundamentally different biomechanics, which makes developing devices that assist both gaits challenging. We show that a portable exosuit that assists hip extension can reduce the metabolic rate of treadmill walking at 1.5 meters per second by 9.3% and that of running at 2.5 meters per second by 4.0% compared with locomotion without the exosuit. These reduction magnitudes are comparable to the effects of taking off 7.4 and 5.7 kilograms during walking and running, respectively, and are in a range that has shown meaningful athletic performance changes. The exosuit automatically switches between actuation profiles for both gaits, on the basis of estimated potential energy fluctuations of the wearer's center of mass. Single-participant experiments show that it is possible to reduce metabolic rates of different running speeds and uphill walking, further demonstrating the exosuit's versatility.

We present an autonomous and portable hip-only soft exosuit, for augmenting human walking and running that assists hip extension by delivering peak forces of 300N to the user. Different fixed assistance profiles for walking and running were applied based on an online classification algorithm. The approach is based on the biomechanical understanding that the center of mass potential energy fluctuations during walking and running are out of phase. Specifically, we monitor the vertical acceleration with an abdomen-mounted IMU at the moment of maximum hip extension. Validation is demonstrated with six subjects on the treadmill and with eight subjects outdoors. Our results demonstrated a 99.99% accuracy on average over the fourteen participants for various speeds (0.5 - 4m/s), slopes (-10 -20%), treadmill and overground terrain, loaded (13.6 kg) and unloaded, Exo On and Exo Off conditions, and different shoe types. Results from an evaluation outdoors overground on the energetics of eight subjects demonstrated a significant reduction for running when comparing Exo On to No Exo (3.9%) and for walking and running when comparing Exo On to Exo Off (12.2% and 8.2% respectively). This study represents the first demonstration of an autonomous wearable robot reducing the energy cost of running. Significant variation in response across subjects was observed, highlighting further improvements may be possible via assistance profile individualization with human-in-the-Ioop optimization.

Soft exosuits are a new approach for assisting with human locomotion, which applies assistive torques to the wearer through functional apparel. In this paper, we present a new version of autonomous multi-joint soft exosuit for gait assistance, particularly designed for overground walking. The soft exosuit assists with ankle plantarflexion, hip flexion, and hip extension, equally distributing the forces between ankle plantarflexion and hip flexion. A mobile actuation system was developed to generate high assistive forces, and Bowden cables are used to transmit the forces to the exosuit. A sensor harness connects two load cells and three IMUs per leg that are used to measure real-time data for a controller that commands desired force profiles as a function of the walking cycle. In addition, a control adaptation method was developed which adjusts control parameters while walking on irregular surfaces. In preliminary studies, the proposed method substantially improved the force consistency while walking over uneven terrain. Specifically, the number of steps where the peak force deviated from the target force decreased from 100 to 57 out of 250 steps, and RMS error on the peak force decreased from 90.0 N to 76.6 N with respect to 300 N target force. Also, a two-subject case study on country-course walking demonstrated the potential of this soft exosuit to improve human energy economy while walking overground.

The risk of recurrent ankle sprains could be reduced if the ankle joint is positioned in a more closed pack position (eversion and dorsiflexion) with enhanced co-activation of Tibialis Anterior (TA) and Peroneus Longus (PL) around heel contact in walking. We examined whether such alteration can be induced by augmenting ankle position error in the inversion and plantarflexion directions.

We have created a lightweight compliant robotic ankle orthotic designed to rehabilitate patients with chronic ankle instability (CAI) through controlled perturbations during gait. This patient population has deficits in ankle sensorimotor control, making it difficult for them to sense and move the ankle and foot properly. This usually leads to recurrent ankle sprains, a factor that has been linked to an increased risk of osteoarthritis and articular degeneration. Current rehabilitation methods are often static, as clinicians cannot provide perturbation in a dynamic condition such as walking. Our device was developed in response to this issue. It can provide controlled force perturbations to the ankle joint in the sagittal and frontal planes during the swing phase of gait using pneumatic artificial muscles. These artificial muscles are back-drivable and extremely light compared to other types of actuation. These features along with the device being a soft orthotic allow patients to correct the error caused by the perturbations in a proactive or reactive manner. The only rigid component is a foot plate that supports the foot and provides attachments to the pneumatic muscles. The entire device weighs approximately 1.1 kg, this lightweight feature allows patients to walk with their natural gait while wearing the device. The device uses rotary encoders to measure the ankle angles as well as force sensors to determine when the foot is in contact with the ground. Initial results show that while wearing the device, plantarflexion and dorsiflexion were virtually unaffected while eversion was slightly increased during swing phase.

Robotic neurorehabilitation is a rapidly growing field in both research and industry. Robotics offer the ability to create less labor-intensive rehabilitation for therapists, while providing an interactive experience for patients. Furthermore, the ability to implement assistive robotic therapy in the home setting has the potential to increase. the frequency of patient rehabilitation sessions while decreasing the overall cost of therapy. Therefore, the design, control, and initial testing of an actuated 2 degree of freedom hand rehabilitation device is presented.A 2 degree of freedom hand rehabilitation device, named the Navigator, is mechanically capable of assistive or resistive mode exercise for flexion and extension of the fingers, as well as pronation and supination of the wrist. A series elastic actuator incorporating a rack and pinion provides actuation to flexion and extension of the fingers. A belt drive is used to provide actuation to pronation and supination of the wrist. Position and load sensors are integrated into both actuators to provide feedback for the control system.The implementation of an impedance control system utilizing position, force, and torque feedback is also presented. Automated control results as well as preliminary pilot data of resistive mode exercises are presented. The impedance controller interacts with a virtual environment. Preliminary results of the controller confirm the efficacy of the device's mechanical design.

Presented is the design, implementation, and initial gait testing of a lightweight, compliant robotic device for ankle rehabilitation. Many patients with neuromuscular disorders suffer deficits in sensorimotor control of the ankle joint, leading to an abnormal walking pattern. Robotic devices have been used to assist ankle rehabilitation. However, these devices are usually heavy and rigid, which can deviate a natural gait pattern. To address these issues, our team has developed a light weight, compliant ankle robotic device actuated by artificial pneumatic muscles. A total of 3 healthy subjects were recruited to test whether the mechanical structure of the device deviates gait. We used a 3-dimensional (3D) motion analysis system to record and analyze subjects' ankle kinematics during gait while walking barefoot and while wearing the device unpowered. The preliminary results suggest that the device caused some, but minimal changes in ankle kinematics during gait. The changes were mainly caused by the device's rigid footplate, used to support the foot and connect to the pneumatic muscles. The preliminary results will be used for future improvement of the device.

Each year in the US, 628,000 people suffer an ankle sprain, and 795,000 suffer a new or recurrent stroke. Due to improved survival rates after stroke, significant increases in stroke population are projected by 2030. So far, there is no cost-effective robotic ankle/balance trainer in the market. In this paper, we present the Virtually-Interfaced Robotic Ankle and Balance Trainer (vi-RABT), a low-cost robotic system that will improve overall ankle / balance strength, mobility and control. The system is equipped with 2 degrees of freedom (DOF) controlled actuation along with complete means of force and angular measurements. The preliminary results on a single robotic footplate confirm the system design. The system will be used for measurement of ankle kinematics, ankle kinetics and balance function, as well as for retraining motor control and strength of the ankle during plantarflexion / dorsiflexion (PF/DF), ankle inversion / eversion (IN/EV) and circumduction motions.