Exoskeleton Device Research Articles

Development and Application of A New Graphene Sensing Exoskeleton Device System for Lower Extremity Walking

In view of the phenomenon that the exoskeleton lower limb walking robot is insensitive and wears less compliance, this project proposes the idea of using wearable sensors composed of graphene and its composite materials to realize the lower limb exoskeleton system. Through the lower limb joint movement mechanism combined with the feature of gait analysis, the design is consistent with human body engineering and meet the demand of rehabilitation in patients with lower limb joints more flexible exoskeleton, using graphene excellent mechanical properties and unique electrical characteristics, and material as the ideal two-dimensional structure, realizes the flexibility design of the sensor and preparation, and further perfect the wearable sensor through visual sensor, Various physiological signals of the human body are monitored to help lower extremity X bone aid meet the needs of patients. The multi-modal signals collected during the gait of the subjects are combined with machine learning methods to achieve accurate identification of the motion intention of patients. Meanwhile, gait parameters are analyzed to facilitate real-time adjustment of the robot. Finally, we hope to provide effective means for the rehabilitation of patients with lower limb motor dysfunction.

A review on design mechanism for self-adapting upper-limb rehabilitation device on finger

Stroke is a common cause which is affecting the lives of elderly. These days such cases are common among young generation also. They may result in damaging the lower or upper limb and oftentimes both. In some cases, the patient can regain their natural range of motion by therapeutic exercises. However, these exercises now involve the use of exoskeleton devices. Therefore, to unveil the different types of self-adapting upper limb rehabilitation devices, an attempt has been made in this paper. The paper will serve as a small inventory of distinct rehabilitation devices available for upper limb with in depth advantages and limitations.[copyright information to be updated in production process]

The Effects of Incline Level on Optimized Lower-Limb Exoskeleton Assistance: A Case Series.

For exoskeletons to be successful in real-world settings, they will need to be effective across a variety of terrains, including on inclines. While some single-joint exoskeletons have assisted incline walking, recent successes in level-ground assistance suggest that greater improvements may be possible by optimizing assistance of the whole leg. To understand how exoskeleton assistance should change with incline, we used human-in-the-loop optimization to find whole-leg exoskeleton assistance torques that minimized metabolic cost on a range of grades. We optimized assistance for three non-disabled, expert participants on 5 degree, 10 degree, and 15 degree inclines using a hip-knee-ankle exoskeleton emulator. For all assisted conditions, the cost of transport was reduced by at least 50% relative to walking in the device with no assistance, which is a large improvement to walking comparable to the benefits of whole-leg assistance on level-ground (N = 3). Optimized extension torque magnitudes and exoskeleton power increased with incline. Hip extension, knee extension and ankle plantarflexion often grew as large as allowed by comfort-based limits. Applied powers on steep inclines were double the powers applied during level-ground walking, indicating that greater exoskeleton power may be optimal in scenarios where biological powers and costs are higher. Future exoskeleton devices could deliver large improvements in walking performance across a range of inclines if they have sufficient torque and power capabilities.

Development and Usability Testing of a Finger Grip Enhancer for the Elderly

As people age, their finger function deteriorates due to muscle, nerve, and brain degeneration. While exercises might delay this deterioration, an invention that enhances elderly people’s pinching abilities is essential. This study aims to design and develop a finger grip enhancer that facilitates the day-to-day pinching activities of elderly people. This research is an extension of a previous study that conceptualised a finger grip enhancer. The device facilitates finger flexion on the thumb and index finger, and weighs 520 g, allowing for improved portability and sufficient force exertion (13.9 N) for day-to-day pinching. To test for usability, eleven subjects aged 65 years and above performed a pinch-lift-hold test on various household objects. The pinch force before and after utilising the device was measured. Using Minitab 18, the statistical significance of using this device was analysed with a paired-samples t-test. With this device, the elderly people’s pinching abilities significantly improved in both pinch force and pinch force steadiness (p < 0.05). The proposed device has the potential to enhance elderly people’s quality of life by supporting a firm pinch in the handling of everyday objects. This research has applicational value in developing exoskeleton devices for patients who require rehabilitation.

Effect of Wearing a Negative Pressure Adherent Exoskeleton Device on the Prognosis of Patients with Skull Loss

Effect of Wearing a Negative Pressure Adherent Exoskeleton Device on the Prognosis of Patients with Skull Loss

Robot-Assisted Training for Upper Limb in Stroke (ROBOTAS): An Observational, Multicenter Study to Identify Determinants of Efficacy.

Background: The loss of arm function is a common and disabling outcome after stroke. Robot-assisted upper limb (UL) training may improve outcomes. The aim of this study was to explore the effect of robot-assisted training using end-effector and exoskeleton robots on UL function following a stroke in real-life clinical practice. Methods: A total of 105 patients affected by a first-ever supratentorial stroke were enrolled in 18 neurorehabilitation centers and treated with electromechanically assisted arm training as an add-on to conventional therapy. Both interventions provided either an exoskeleton or an end-effector device (as per clinical practice) and consisted of 20 sessions (3/5 times per week; 6–8 weeks). Patients were assessed by validated UL scales at baseline (T0), post-treatment (T1), and at three-month follow-up (T2). The primary outcome was the Fugl-Meyer Assessment for the upper extremity (FMA-UE). Results: FMA-UE improved at T1 by 6 points on average in the end-effector group and 11 points on average in the exoskeleton group (p < 0.0001). Exoskeletons were more effective in the subacute phase, whereas the end-effectors were more effective in the chronic phase (p < 0.0001). Conclusions: robot-assisted training might help improve UL function in stroke patients as an add-on treatment in both subacute and chronic stages. Pragmatic and highmethodological studies are needed to confirm the showed effectiveness of the exoskeleton and end-effector devices.

Utility of Inter-subject Transfer Learning for Wearable-Sensor-Based Joint Torque Prediction Models.

Generalizability between individuals and groups is often a significant hurdle in model development for human subjects research. In the domain of wearable-sensor-controlled exoskeleton devices, the ability to generalize models across subjects or fine-tune more general models to individual subjects is key to enabling widespread adoption of these technologies. Transfer learning techniques applied to machine learning models afford the ability to apply and investigate the viability and utility such knowledge-transfer scenarios. This paper investigates the utility of single- and multi-subject based parameter transfer on LSTM models trained for "sensor-to-joint torque" prediction tasks, with regards to task performance and computational resources required for network training. We find that parameter transfer between both single- and multi-subject models provide useful knowledge transfer, with varying results across specific "source" and "target" subject pairings. This could be leveraged to lower model training time or computational cost in compute-constrained environments or, with further study to understand causal factors of the observed variance in performance across source and target pairings, to minimize data collection and model retraining requirements to select and personalize a generic model for personalized wearable-sensor-based joint torque prediction technologies.

Flexohand: A Hybrid Exoskeleton-Based Novel Hand Rehabilitation Device.

Home-based hand rehabilitation has excellent potential as it may reduce patient dropouts due to travel, transportation, and insurance constraints. Being able to perform exercises precisely, accurately, and in a repetitive manner, robot-aided portable devices have gained much traction these days in hand rehabilitation. However, existing devices fall short in allowing some key natural movements, which are crucial to achieving full potential motion in performing activities of daily living. Firstly, existing exoskeleton type devices often restrict or suffer from uncontrolled wrist and forearm movement during finger exercises due to their setup of actuation and transmission mechanism. Secondly, they restrict passive metacarpophalangeal (MCP) abduction–adduction during MCP flexion–extension motion. Lastly, though a few of them can provide isolated finger ROM, none of them can offer isolated joint motion as per therapeutic need. All these natural movements are crucial for effective robot-aided finger rehabilitation. To bridge these gaps, in this research, a novel lightweight robotic device, namely “Flexohand”, has been developed for hand rehabilitation. A novel compliant mechanism has been developed and included in Flexohand to compensate for the passive movement of MCP abduction–adduction. The isolated and composite digit joint flexion–extension has been achieved by integrating a combination of sliding locks for IP joints and a wire locking system for finger MCP joints. Besides, the intuitive design of Flexohand inherently allows wrist joint movement during hand digit exercises. Experiments of passive exercises involving isolated joint motion, composite joint motions of individual fingers, and isolated joint motion of multiple fingers have been conducted to validate the functionality of the developed device. The experimental results show that Flexohand addresses the limitations of existing robot-aided hand rehabilitation devices.

Development of Robotic Rehabilitation Device for Spasticity Treatment of Acute Spinal Cord Injury Patients

As spasticity is a major cause of illness in patients that suffer from spinal cord injury (SCI), there are several limitations in the present robotic-based therapy for the treatment of acute SCI patients. A large literature is present for the use of full body exoskeletons, but due to their limitations such as uneasiness due to repetitive motion, does not meet the anthropometric range. As manual therapy is tiresome, a need for ankle-foot therapy exoskeleton was felt and Ankle-Foot Orthosis was developed. This paper presents an ankle-foot therapy exoskeleton device for spasticity treatment of acute SCI patients to reduce the manual efforts of physiotherapists. The proposed device has one Degree of Freedom (DOF) in the sagittal plane in ankle joint. This paper analyses the control design of the prototype and clinical trial results on SCI patients, which show that the proposed prototype is viable in improving the range of ankle motion alleviating the spasticity with p = 0.000365.

YÜRÜME, OTURMA-KALKMA VE MERDİVEN ÇIKMA SIRASINDA YARDIMCI OLAN DİZ DIŞ İSKELETİNİN TASARIMI

In this study, we present a knee exoskeleton that assists weight acceptance in walking, sit-to-stand and stair ascending. Working principle of the exoskeleton device is inspired from the bio-mechanical data of natural human gait, sit to stance and stair ascent motions. First, we analyze the natural gait data to identify the weight acceptance behavior of the knee joint. Then we build a model for sit to stand motion with an elastic element. After that, stair ascent data is analyzed in a similar manner. Then, we define the appropriate elastic elements, their coefficients and motor requirements if necessary, for these specific tasks. Finally, we present the CAD model of the proposed knee exoskeleton.

Physiologic signaling and viability of the muscle cuff regenerative peripheral nerve interface (MC-RPNI) for intact peripheral nerves

Background. Robotic exoskeleton devices have become a promising modality for restoration of extremity function in individuals with limb loss or functional weakness. However, there exists no consistent or reliable way to record efferent motor action potentials from intact peripheral nerves to control device movement. Peripheral nerve motor action potentials are similar in amplitude to that of background noise, producing an unfavorable signal-to-noise ratio (SNR) that makes these signals difficult to detect and interpret. To address this issue, we have developed the muscle cuff regenerative peripheral nerve interface (MC-RPNI), a construct consisting of a free skeletal muscle graft wrapped circumferentially around an intact peripheral nerve. Over time, the muscle graft regenerates, and the intact nerve undergoes collateral axonal sprouting to reinnervate the muscle. The MC-RPNI amplifies efferent motor action potentials by several magnitudes, thereby increasing the SNR, allowing for higher fidelity signaling and detection of motor intention. The goal of this study was to characterize the signaling capabilities and viability of the MC-RPNI over time. Methods. Thirty-seven rats were randomly assigned to one of five experimental groups (Groups A–E). For MC-RPNI animals, their contralateral extensor digitorum longus (EDL) muscle was harvested and trimmed to either 8 mm (Group A) or 13 mm (Group B) in length, wrapped circumferentially around the intact ipsilateral common peroneal (CP) nerve, secured, and allowed to heal for 3 months. Additionally, one 8 mm (Group C) and one 13 mm (Group D) length group had an epineurial window created in the CP nerve immediately preceding MC-RPNI creation. Group E consisted of sham surgery animals. At 3 months, electrophysiologic analyses were conducted to determine the signaling capabilities of the MC-RPNI. Additionally, electromyography and isometric force analyses were performed on the CP-innervated EDL to determine the effects of the MC-RPNI on end organ function. Following evaluation, the CP nerve, MC-RPNI, and ipsilateral EDL muscle were harvested for histomorphometric analysis. Results. Study endpoint analysis was performed at 3 months post-surgery. All rats displayed visible muscle contractions in both the MC-RPNI and EDL following proximal CP nerve stimulation. Compound muscle action potentials were recorded from the MC-RPNI following proximal CP nerve stimulation and ranged from 3.67 ± 0.58 mV to 6.04 ± 1.01 mV, providing efferent motor action potential amplification of 10–20 times that of a normal physiologic nerve action potential. Maximum tetanic isometric force (F o) testing of the distally-innervated EDL muscle in MC-RPNI groups produced F o (2341 ± 114 mN–2832 ± 102 mN) similar to controls (2497 ± 122 mN), thus demonstrating that creation of MC-RPNIs did not adversely impact the function of the distally-innervated EDL muscle. Overall, comparison between all MC-RPNI sub-groups did not reveal any statistically significant differences in signaling capabilities or negative effects on distal-innervated muscle function as compared to the control group. Conclusions. MC-RPNIs have the capability to provide efferent motor action potential amplification from intact nerves without adversely impacting distal muscle function. Neither the size of the muscle graft nor the presence of an epineurial window in the nerve had any significant impact on the ability of the MC-RPNI to amplify efferent motor action potentials from intact nerves. These results support the potential for the MC-RPNI to serve as a biologic nerve interface to control advanced exoskeleton devices.

QS7: Physiologic Signaling of the Muscle Cuff Regenerative Peripheral Nerve Interface (MC-RPNI) During Volitional Behavior

Purpose:Exoskeletons have become a promising device to restore extremity function to those with limb weakness. However, these devices have not become widely adopted due to the inadequacy of current nerve interfacing methods. The Muscle Cuff Regenerative Peripheral Nerve Interface (MC-RPNI) was developed as a potential solution to this problem. Consisting of a segment of autologous free muscle secured around an intact nerve, the MC-RPNI is able to regenerate and reinnervate, amplifying its contained nerve’s signals through generation of EMG signals. These amplified, high-fidelity signals can then be used to intuitively and accurately control exoskeletons. The purpose of this study was to characterize MC-RPNI physiologic signaling during volitional behavior and determine long-term effects on the associated nerve.Methods:Eighteen rats were randomly assigned to one of three groups: (1) sham surgery/control; (2) nerve transection; and (3) MC-RPNI. MC-RPNIs were surgically fabricated by wrapping isogenic donor muscle graft circumferentially around the common peroneal (CP) nerve. At six months, CP nerve cuff electrodes were implanted in Groups 1 and 2,and patch electrodes were placed on all MC-RPNIs. Gait analysis and electrophysiological evaluations were performed the following day. Rats were trained to walk on a treadmill, and electrode recordings were obtained and correlated with gait videocapture. All rats had their proximal CP nerve stimulated, with efferent signals obtained at (1) downstream nerve (CSNAP), (2) MC-RPNI (CMAP), and (3) downstream-innervated extensor digitorum longus (EDL) muscle (CMAP). EDL muscle force testing was also performed following stimulation of the CP nerve.Results:All MC-RPNIs remained viable and demonstrated appropriate regeneration, revascularization, and reinnervation on histology. The MC-RPNI was found to generate large-amplitude CMAPs (2.77+/-0.926mV), amplifying its associated nerve’s signal (50.5+/-8.18µV) over 50-fold on average. The MC-RPNI was not found to affect muscle function when evaluating downstream-innervated EDL CMAPs (control: 13.4+/-2.33mV vs MC-RPNI: 14.1+/-1.44mV) or maximal twitch force (control: 562+/-70.8mN vs MC-RPNI: 653+/-34.6mN). On gait analysis, recordings from the MC-RPNI correlated with the toe-off phase of gait; for the control groups, nerve signaling could not be differentiated from background noise. When comparing MC-RPNI to control animal gait, no significant differences were noted on qualitative or joint-angle analysis.Conclusion:The MC-RPNI has the ability to chronically amplify physiologic nerve signals from intact peripheral nerves by several magnitudes while avoiding functional impairment of downstream-innervated muscle. This amplification has the capability to facilitate high accuracy detection of motor intent in order to intuitively and reliably control advanced exoskeleton devices.

Finger Exoskeleton in Simple Motor Rehabilitation Therapy on Arm and Hand Muscle Ability of Post-Stroke Sufferers

Post-stroke sufferers will generally experience weakness on one side of the body, balance, vision, sensory, motor, and cognitive. In West Kalimantan, the estimated stroke sufferer in 2013 was 25,195 people. Based on data from the Public Hospital of Dr. Soedarso Pontianak shows a significant increase from January 2018 to December 2018 totaling 722 people. The research objective was to assess the effectiveness of the finger exoskeleton tool in simple motor therapy on the ability of the client's arm and hand muscles after a stroke. This study used a quantitative approach with a quasi-experimental design. Pre-test and Post-test Nonequivalent Control Group with two groups, which were the control group of 12 people and the intervention group of 12 people with finger exoskeleton tools. The statistical test used was the independent t test and paired t test. Measurement of muscle ability with the Action Research Arm Test. Analysis of the difference in total scores between before and after treatment in the intervention group using Paired T-Test obtained a p-value of 0.000 (p value &lt;0.05) and in the control group using the Wilcoxon test a p-value of 0.016 (p value &lt;0.05). It shows that there is a significant difference in the total score between before and after finger exoskeleton therapy and range of motion. Intervention of finger exoskeleton assistive devices in simple motor rehabilitation therapy is effective in increasing the ability of the client's arm and hand muscles after stroke. It is recommended to make another finger rehabilitation tool with a more optimal design according to the parameters, which are the severity of the client after stroke, subject kinematics, control of movement torque and adaptation between the subject and the robotic device used.

Output Tracking Performance of Active Exoskeleton Robot Using Sliding Mode Control

Background:: Assistive exoskeleton robot is required to improve the control of exoskeleton joints. The robust response of all joint controls is planned to improve the performance of joint tracking control. Recent patents of an assistive exoskeleton robot concern to explore the system design and integration have been used. Objective:: To design and improve the control performance for gain more stability locomotion of exoskeleton device by using the Sliding Mode Control (SMC) technique, and to explore the recent patents of an assistive exoskeleton robots and methods. Methods:: The recent patents of assistive exoskeleton robots currently investigate in this research. The trajectory generation of gait cycle is approximated using a polynomial equation of the ninth order in the curve fitting of the Human Clinical Gait Cycle (CGC) of lower limb joints. The position and velocity control along the gait cycle are controlled using SMC methods. The robust design of controller performance of position and velocity control for each joint is established via design simulation in three cases. Results:: The output tracking performance of hip, knee, and ankle joint’s position and velocity shows the controller performance. Three cases of control design study are validated by simulation methods. Conclusion:: The SMC controller significantly improves the motion control of exoskeleton robot, even with disturbance affecting the system. Thus, it is robust to external forces with humans in the loop system. A steepest command trajectory will cause a lower output tracking response and vice versa.

Evaluation of a passive low-back support exoskeleton (Ergo-Vest) for manual waste collection

The purpose of study was to determine the biomechanical, physiological, and subjective effect of a Passive Exoskeleton device (called Ergo-Vest) among 20 waste collectors in the working environment. Compression force and moment on L4/L5 related to 400 critical postures of the participants were estimated using the 3DSSPP software. The heart rate and energy expenditure are measured as the physiological strain using the Polar RS400 Heart Rate Monitor. Borg scale perceived exertion, system usability scale, and ergonomic design indicators of the device were collected as the subjective parameters. Compression force and moment on L4/L5 disc were decreased when the Ergo-Vest was utilised. There was no significant difference in energy expenditure and heart rate with and without the device. The workers' perceived physical exertion was decreased while using the Ergo-Vest. From the perspective of end users, the usability and ergonomic design features of the Ergo-Vest was acceptable. Practitioner summary: The prevalence of musculoskeletal disorders is high among the Iranian waste collectors. To mitigate this occupational problem, the effect of a passive exoskeleton for lower-back support (Ergo-Vest) was investigated on the workers' spine loading, physiological parameters, and perceived physical exertion. The result shows spine force reduction and lower subjective responses.

A Review: Sensory System, Data Processing, Actuator Type on a Hand Exoskeleton Design

A rehabilitation device for a post-stroke is essential because stroke attacks can cause disable to part or half of the human body. An exoskeleton could be a vital device for rehabilitation for a post-stroke patient. Several studies have proposed the exoskeleton design for rehabilitation purposes to a human limb disorder. This study aims to review the state-of-the-art of hand exoskeleton devices based on myoelectric or any other sensors. This paper is expected to contribute to design a hand exoskeleton device using both myoelectric and force sensors. This was achieved by reviewing several articles related to the development of the exoskeleton, especially in the sensor system, data processing, and actuator system. The results show that the use of Ag electrode disposable Ag (AgCl) is still commonly found to detect the movement of the fingers on the hand because this sensor can reduce the artifact noise. The use of myo-armband is also found in several studies because it has wireless properties so that it is easy to use. In terms of processors, Arduino microcontrollers are more widely used than others. In order to activate the hand exoskeleton, servo motors are more widely used to actuate the finger joints, which is more precise than other actuators. In a further development, integration between exoskeleton systems and information systems will be an expected challenge. Furthermore, hopefully, the development of this exoskeleton can be applied as a rehabilitation device for patients with malfunction or hand paralysis.

Effects of robot-assisted gait training on postural instability in Parkinson's disease: a systematic review.

Postural instability is a cardinal feature of Parkinson's disease, together with rest tremor, rigidity and bradykinesia. It is a highly disabling symptom that becomes increasingly common with disease progression and represents a major source of reduced quality of life in patients with Parkinson's disease. Rehabilitation aims to enable patients with Parkinson's disease to maintain their maximum level of mobility, activity and independence. To date, a wide range of rehabilitation approaches has been employed to treat postural instability in Parkinson's disease, including robotic training. Our main aim was to conduct a systematic review of current literature about the effects of robot-assisted gait training on postural instability in patients with Parkinson's disease. A systematic search using the following MeSH terms "Parkinson disease," "postural balance," "robotics," "rehabilitation" AND string "robotics [mh]" OR "robot-assisted" OR "electromechanical" AND "rehabilitation [mh]" OR "training" AND "postural balance [mh]" was conducted on PubMed, Cochrane Library and Pedro electronic databases. Full text articles in English published up to December 2020 were included. Data about patient characteristics, robotic devices, treatment procedures and outcome measures were considered. Every included article got checked for quality. Level of evidence was defined for all studies. Three authors independently extracted and verified data. In total, 18 articles (2 systematic reviews, 9 randomized controlled trials, 4 uncontrolled studies and 3 case series/case reports) were included. Both end-effector and exoskeleton devices were investigated as to robot-assisted gait training modalities. No clear relationship between treatment parameters and clinical conditions was observed. We found a high level of evidence about the effects of robot-assisted gait training on balance and freezing of gait in patients with Parkinson's disease. This systematic review provides to the reader a complete overview of current literature and levels of evidence about the effects of robot-assisted gait training on postural instability issues (static and dynamic balance, freezing of gait, falls, confidence in activities of daily living and gait parameters related to balance skills) in patients with Parkinson's disease.

고령자 및 편마비 환자를 대상으로 강력 파지 동작에 최적화된 외골격 보조 장치의 개발

본 연구에서는 고령자 및 편마비 환자를 대상으로 하는 양방향 외골격 장치의 개발을 목표로 한다. 개발된 장치는 강력 파지 동작을 중점으로 제작, 장비의 부피, 무게, 제작 단가를 낮췄으며, 엄지의 위치 제어 및 파지 동작 시 힘의 세기 조절을 통해 일상생활 속 활용도를 증가시켰다. 장비제공힘 10 N, ROM 40 degree 이상의 성능을 가지며, CATIA 기반의 3D 모델링을 활용하여 설계를 진행하였다. 장비의 각 부분은 용도에 따라 개별적으로 설계되었으며, PLA, TPU, 실리콘 소재를 활용하여 제작되었다. 힘 데이터의 직접 측정 및 쉬운 조작을 통해 사용자 피드백 및 치료사의 판단을 보조할 수 있을 것으로 예상된다.

Observations of human muscle response during daily life activities of biped kinematics using a musculoskeletal simulator

Research in biomechanics has numerous applications including rehabilitation which helps in the fabrication of assistive devices. The Assistive devices or exoskeletons are used to serve the patients affected by stroke and spinal cord malfunctioning. These devices are programmed to follow a fixed redundant gait cycle and are lacking in producing natural movement of the gait. To overcome this limitation and make the device more user comfortable during usage of their daily life activities, a thorough study was done using an open source software that contributed to the design of exoskeleton device for the subject. In the current study, a simulation of various daily life activities are thoroughly studied using a musculoskeletal simulator package like OpenSim. The paper presents the observations of muscle responses from ground reaction forces with minimized metabolic cost function in various activities of daily living such as sitting to standing, standing to sitting, jumping, twisting suddenly while walking and turning suddenly. The study deliberates the inputs for developing more comfortable exoskeletons in performing tasks in a more sophisticated manner.

67553 Exoskeleton dynamics alter upper-limb coordination in a virtual reality reaching task

ABSTRACT IMPACT: This proof-of-concept study demonstrates that systematically altering limb dynamics with two exoskeleton devices alters ingrained, bilateral upper-limb coordination with the potential to rehabilitate functional reaching in chronic stroke survivors OBJECTIVES/GOALS: Advances in virtual reality and exoskeleton technologies have allowed researchers to alter upper limb coordination with more precision than ever before. The goal of this study was to systematically enhance the use of the nondominant limb during a bimanual reaching task, with an eye towards improving rehabilitative strategies post stroke. METHODS/STUDY POPULATION: Healthy, right-handed volunteers performed a bimanual reaching task in virtual reality (VR) space while simultaneously moving under the influence of two exoskeleton devices. The VR task had participants move a shared cursor, displayed at the midpoint between the hands, to targets arranged at shoulder and eye levels and located at 70% of full arm extension. Two exoskeleton devices applied either resistive torque to the dominant limb or assistive torque to the non-dominant limb. Three-dimensional hand position data were recorded at 50 Hz and analyzed offline. The primary outcome measure was relative contribution, calculated as the ratio of dominant/non-dominant displacement. RESULTS/ANTICIPATED RESULTS: Preliminary results from 3 participants showed that during baseline trials, when no torque was applied by the exoskeletons, relative contribution was 50.6% in favor of the dominant hand, with the dominant hand reaching on average 1.1cm farther than the left. When the exoskeletons resisted movement in the dominant limb while simultaneously assisting movement in the non-dominant limb, relative contribution was 49.7% indicating an increase in non-dominant limb usage. Further analysis showed that this effect was driven by one participant who reached 3.7cm farther with her non-dominant hand compared to baseline. DISCUSSION/SIGNIFICANCE OF FINDINGS: These pilot data suggest our testing platform is capable of altering normal coordination patterns and is likely the result of participants adopting an optimal control strategy imposed by the shared cursor. These findings will form the basis for a rehabilitation intervention to promote the use of the paretic limb in chronic stroke survivors.