Posts Tagged Exoskeleton

[Abstract] Automated design of a custom-made hand rehabilitation robot – Full Text PDF


A frequent consequence of stroke is a limited hand function. Numerous studies have shown, that repetitive passive training enhances the rehabilitation process. As there are high anthropometric variances in hand and finger anatomy, this contribution presents a custom-made hand rehabilitation robot. The individual design is proposed to ensure an ergonomic interface which allows long-time wearing. To provide a cost-effective production, we present an automated design process. The individual fingers are manufactured monolithically using the selective laser sintering of polyamide. The presented device is portable and can be used for training as well as for grasping things.


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via Automated design of a custom-made hand rehabilitation robot | Transactions on Additive Manufacturing Meets Medicine

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[Abstract] Wearable Hand Exoskeleton Systems for Virtual Reality and Rehabilitation


The aim is to overcome the limitations of conventional systems in terms of both wearability and portability. As the hand receives diverse physical information and manipulates different type of objects, conventional systems contain many sensors and actuators, and are both large and heavy. Thus, hand exoskeleton systems exhibiting high wearability and portability while measuring finger motions and delivering forces would be highly valuable. For VR hand exoskeleton systems, a wearable hand exoskeleton system with force-controllable actuator modules was developed to ensure free finger motion and force mode control. The linkage structure ensures motion with three degrees of freedom (DOF) and provides a large fingertip workspace; the finger postures assumed when interacting with objects are appropriate. A series elastic actuator (SEA) with an actuator and an elastic element was used to fabricate compact actuator modules. Actuator friction was eliminated using a friction compensation algorithm. A proportional differential (PD) controller, optimized by a linear quadratic (LQ) method featuring a disturbance observer (DOB), was used to ensure accurate force mode control even during motion. The force control performance of the actuator module was verified in force generation experiments including stationary and arbitrary end-effector motions. The forces applied to the fingertips, which are the principal parts of the hand that interact with objects, were kinematically analyzed via both simulations and experiments. To overcome the weak point of previous system, a wearable hand exoskeleton system featuring finger motion measurement and force feedback was developed and evaluated in terms of user experience (UX). The finger structures for the thumb, index, and middle fingers, which play important roles when grasping objects, satisfy full range of motion (ROM). The system estimates all joint angles of these three digits using a dedicated algorithm; measurement accuracy was experimentally evaluated to verify system performance. The UX performance was evaluated by 15 undergraduate students who completed questionnaires assessing usability and utilitarian value following trials conducted in the laboratory. All subjects were highly satisfied with both usability and the utilitarian nature of the system, not only because control and feedback were intuitive but also because performance was accurate. For rehabilitation, a highly portable exoskeleton featuring flexion/extension finger exercises was developed. The exoskeleton features two four-bar linkages reflecting the natural metacarpophalangeal (MCP) and proximal phalangeal (PIP) joint angles. During optimization, the design parameters were adjusted to reflect normal finger trajectories, which vary by finger length and finger joint ROM. To allow for passive physical impedance, a spring was installed to generate the forces that guided the fingers. The moments transmitted to the MCP and PIP joints were estimated via finite element method (FEM) analysis and the cross-sectional areas of the links were manually designed by reference to the expected joint moments. Finger motion and force distribution experiments verified that the system guided the fingers effectively, allowed for the desired finger motions, and distributed the required moments to the joints (as revealed by FEM analysis).; This thesis reports the development of hand exoskeleton systems, for use in virtual reality (VR) environments and for hand rehabilitation

via ScholarWorks: Wearable Hand Exoskeleton Systems for Virtual Reality and Rehabilitation

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[Abstract] Exoskeleton design and adaptive compliance control for hand rehabilitation

An adaptive robotic system has been developed to be used for hand rehabilitation. Previously developed exoskeletons are either very complex in terms of mechanism, hardware and software, or simple but have limited functionality only for a specific rehabilitation task. Some of these studies use simple position controllers considering only to improve the trajectory tracking performance of the exoskeleton which is inadequate in terms of safety and health of the patient. Some of them focus only on either passive or active rehabilitation, but not both together. Some others use EMG signals to assist the patient, but this time active rehabilitation is impossible unless different designs and control strategies are not developed. The proposed mechanical structure is extremely simple. The middle and the proximal phalanxes are used as a link of consecutively connected two 4-bar mechanisms, respectively. The PIP and MCP joints are actuated by a single electro mechanical cylinder to produce complex flexion and extension movements. It is simpler than similar ones from aspect with the mechanical structure and the biodynamic fit of the hand, making it practicable in terms of production and personal usage. Simple design lets to implement adaptive compliance controller for all active and passive rehabilitation tasks, instead of developing complex and different strategies for different rehabilitation tasks. Furthermore, using the Luenberger observer for unmeasured velocity state variable, an on-line estimation method is used to estimate the dynamic parameters of the system. This makes possible to estimate the force exerted by the patient as well, without a force sensor.


via Exoskeleton design and adaptive compliance control for hand rehabilitation – Gazi Akgun, Ahmet Emre Cetin, Erkan Kaplanoglu,

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[Abstract + References] Upper-Limb Exoskeletons for Stroke Rehabilitation – Conference paper


Upper-limb exoskeletons provide high-intensity, repetitive, task-specific, interactive and individualized training, making effective use of neuroplasticity for functional recovery in neurological patients. Most exoskeletons have robot axes aligned with the anatomical axes of the subject and provide direct control of individual joints. Recently, novel mechanical structures and actuation mechanisms have been proposed, but still result in bulky and heavy exoskeletons, limiting their applicability into clinical practice. Technological efforts are needed to promote light and wearable exoskeletons that implement active-assistive controllers, providing “assisted-as-needed” rehabilitation therapy, towards patient’s motivation and self-esteem. An overview of upper-limb exoskeletons, including mechanical design and control algorithms, will be provided. Special focus will be put on the current evidence about the efficacy of wearable robotic technologies on motor recovery and about other therapies that can be combined with exoskeletons to improve their therapeutic effects.


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via Upper-Limb Exoskeletons for Stroke Rehabilitation | SpringerLink

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[Abstract] Robotic Exoskeleton for Wrist and Fingers Joint in Post-Stroke Neuro-Rehabilitation for Low-Resource Settings


Robots have the potential to help provide exercise therapy in a repeatable and reproducible manner for stroke survivors. To facilitate rehabilitation of the wrist and fingers joint, an electromechanical exoskeleton was developed that simultaneously moves the wrist and metacarpophalangeal joints.
The device was designed for the ease of manufacturing and maintenance, with specific considerations for countries with limited resources. Active participation of the user is ensured by the implementation of electromyographic control and visual feedback of performance. Muscle activity requirements, movement parameters, range of motion, and speed of the device can all be customized to meet the needs of the user.
Twelve stroke survivors, ranging from the subacute to chronic phases of recovery (mean 10.6 months post-stroke) participated in a pilot study with the device. Participants completed 20 sessions, each lasting 45 minutes. Overall, subjects exhibited statistically significant changes (p < 0.05) in clinical outcome measures following the treatment, with the Fugl-Meyer Stroke Assessment score for the upper extremity increasing from 36 to 50 and the Barthel Index increasing from 74 to 89. Active range of wrist motion increased by 190 while spasticity decreased from 1.75 to 1.29 on the Modified Ashworth Scale.
Thus, this device shows promise for improving rehabilitation outcomes, especially for patients in countries with limited resources.

via Robotic Exoskeleton for Wrist and Fingers Joint in Post-Stroke Neuro-Rehabilitation for Low-Resource Settings – IEEE Journals & Magazine

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[VIDEO] Hocoma Lokomat Product Presentation | UK – YouTube

Relearn how to walk from the beginning with Hocoma’s Lokomat, a robotic-assisted therapy solution that enables intensive gait training. The Lokomat uses an individually adjustable exoskeleton combined with dynamic body weight support. Summit Medical and Scientific are UK distributors for Hocoma. Contact us about the Hocoma Lokomat in the UK, and read more on our website:…


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[Systematic Review] Exoskeletons With Virtual Reality, Augmented Reality, and Gamification for Stroke Patients’ Rehabilitation: Systematic Review – Full Text


Background: Robot-assisted therapy has become a promising technology in the field of rehabilitation for poststroke patients with motor disorders. Motivation during the rehabilitation process is a top priority for most stroke survivors. With current advancements in technology there has been the introduction of virtual reality (VR), augmented reality (AR), customizable games, or a combination thereof, that aid robotic therapy in retaining, or increasing the interests of, patients so they keep performing their exercises. However, there are gaps in the evidence regarding the transition from clinical rehabilitation to home-based therapy which calls for an updated synthesis of the literature that showcases this trend. The present review proposes a categorization of these studies according to technologies used, and details research in both upper limb and lower limb applications.

Objective: The goal of this work was to review the practices and technologies implemented in the rehabilitation of poststroke patients. It aims to assess the effectiveness of exoskeleton robotics in conjunction with any of the three technologies (VR, AR, or gamification) in improving activity and participation in poststroke survivors.

Methods: A systematic search of the literature on exoskeleton robotics applied with any of the three technologies of interest (VR, AR, or gamification) was performed in the following databases: MEDLINE, EMBASE, Science Direct & The Cochrane Library. Exoskeleton-based studies that did not include any VR, AR or gamification elements were excluded, but publications from the years 2010 to 2017 were included. Results in the form of improvements in the patients’ condition were also recorded and taken into consideration in determining the effectiveness of any of the therapies on the patients.

Results: Thirty studies were identified based on the inclusion criteria, and this included randomized controlled trials as well as exploratory research pieces. There were a total of about 385 participants across the various studies. The use of technologies such as VR-, AR-, or gamification-based exoskeletons could fill the transition from the clinic to a home-based setting. Our analysis showed that there were general improvements in the motor function of patients using the novel interfacing techniques with exoskeletons. This categorization of studies helps with understanding the scope of rehabilitation therapies that can be successfully arranged for home-based rehabilitation.

Conclusions: Future studies are necessary to explore various types of customizable games required to retain or increase the motivation of patients going through the individual therapies.



Stroke refers to a sudden, often catastrophic neurological event that can lead to long-term adult disability. The American Heart Association (AHA) is responsible for providing up-to-date statistics related to heart disease and stroke. According to Benjamin et al [1], the AHA released a 2017 statistics report on heart disease and stroke that stated that approximately 795,000 stroke episodes occur in the US each year. With current advancements in medical technology there has been a decrease in the rate of stroke incidents, but it can still cause paralysis and muscle weakness. Such impairments can result in motor deficits that disturb a stroke survivor’s capacity to live independently.

There are several reasons for stroke occurrence, which could be related to an increased risk of a collection of symptoms caused by disorders affecting the brain (eg, dementia) [2]. Various rehabilitation techniques have been used in the area of rehabilitation-based interactive technology to assist patients in recovering from impairments, and those techniques come under the umbrella of conventional therapy, exoskeleton or robot-aided therapy, virtual reality (VR) or augmented reality (AR) therapy, games-based therapy, or a combination of any of these. These forms of therapy can be done either in the clinic or in an in-home setting. In addition to these, there is a new technology known as telerehabilitation [3] that leverages the use of VR in home settings by providing patients access to real-time rehabilitation services through the internet while they sit at home.

One of the most effective techniques is robot-aided therapy, which has been gradually increasing in use primarily because patients may consider traditional rehabilitation therapy to be tiring and exhaustive. This may decrease their motivation and cohesion to the treatment, thus resulting in only minor improvement in the health of poststroke patients [46]. Various experimental evidence suggests that robot-assisted (or exoskeleton) rehabilitation has been effective in keeping patients motivated and interested in treatment for both upper or lower limb impairments [7,8]. With advancements in technology, there has also been an uptake of VR, AR, and Gamification for the purposes of rehabilitation [9], along with robotic rehabilitation [10,11], primarily to increase engagement, immersion and motivation on behalf of the patient. Both Colombo et al and Alankus et al [12,13] concluded and showed the positive effect of exoskeleton robots and games in poststroke rehabilitation. Wearable devices such as exoskeletons can also relay real-time feedback for any VR-based interactions [14].

Apart from these studies, Housman et al [15] showed user satisfaction survey results in which 90% of participants agreed to the fact that robot- or games-assisted therapies were less confusing, and improvements were very easy to track compared to traditional or conventional therapies. Further, it is thought that gamification can increase repetition, engagement, and range of care within the context of rehabilitation [16,17]. Games are not only useful for the field of rehabilitation, but they are also considered to be highly impactful and relevant in other medical and health fields. Russoniello et al [18] conducted a randomized controlled trial (RCT) study in which the effects of video games on stress-related disorders were tested, with the conclusion being that games were beneficial for their prevention and treatment. In another study, children who had cerebral palsy made use of a game (EyeToy) which was able to improve their upper extremity functions over time [19].



Continue —->  JRAT – Exoskeletons With Virtual Reality, Augmented Reality, and Gamification for Stroke Patients’ Rehabilitation: Systematic Review | Mubin | JMIR Rehabilitation and Assistive Technologies

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[Abstract] An Elbow Exoskeleton for Upper Limb Rehabilitation With Series Elastic Actuator and Cable-Driven Differential


Movement impairments resulting from neurologic injuries, such as stroke, can be treated with robotic exoskeletons that assist with movement retraining. Exoskeleton designs benefit from low impedance and accurate torque control. We designed a two-degrees-of-freedom tethered exoskeleton that can provide independent torque control on elbow flexion/extension and forearm supination/pronation. Two identical series elastic actuators (SEAs) are used to actuate the exoskeleton. The two SEAs are coupled through a novel cable-driven differential. The exoskeleton is compact and lightweight, with a mass of 0.9 kg. Applied rms torque errors were less than 0.19 Nm. Benchtop tests demonstrated a torque rise time of approximately 0.1 s, a torque control bandwidth of 3.7 Hz, and an impedance of less than 0.03 Nm/° at 1 Hz. The controller can simulate a stable maximum wall stiffness of 0.45 Nm/°. The overall performance is adequate for robotic therapy applications and the novelty of the design is discussed.

via An Elbow Exoskeleton for Upper Limb Rehabilitation With Series Elastic Actuator and Cable-Driven Differential – IEEE Journals & Magazine

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[Abstract] Robotic Techniques Used for Increasing Improvement Rate In The Rehabilitation Process Of Upper Limb Stroke Patients – Full Text PDF


The rate of stroke patients in Pakistan is increasing, resulting in the decrease mobility of the patients. The movement of upper limb stoke patient is decreased due to the weakness and loss of joint control in his upper body. To improve the coordination of movement of the upper limb stroke patients, many methods e.g. passive and active modes for improving the disrupted mobility are introduced. The objectives of this paper are to first review the studies on upper limb stroke patients and the techniques used for increasing the improvement rate through physical therapy by exoskeleton and evaluation of the performance of the patient using methods such as quantification and graphical representations so that it can be shown to the patient for his motivation to improve further. The paper introduces a mechanical design of exoskeleton with 1 degree of freedom for elbow and 2 degrees of freedom for shoulder movement for rehabilitation of joints of stoke patients. It also mentions the safety that will be taken in the process so that the exoskeleton is safe to use when it is in contact with human. The model of the exoskeleton has the characteristic of being modular and easily operable and use admittance control strategy. Control strategy of the exoskeleton is discussed to maintain the position and orientation of the device and also is able to cater the gravitational attraction which plays an important part in the movement of the actuators. The mathematical model of motion attained due to the degrees of freedom of the exoskeleton is then evaluated and the lastly areas where the future work of exoskeleton can be done are discussed.

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via Robotic Techniques Used for Increasing Improvement Rate In The Rehabilitation Process Of Upper Limb Stroke Patients | Sukkur IBA Journal of Computing and Mathematical Sciences

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[WEB PAGE] Ekso Bionics Unveils the EksoNR Neurorehabilitation Device

EksoNR, the latest exoskeleton from Ekso Bionics, features EksoView, a new touchscreen controller that allows therapists to intuitively adapt assistance to challenge patients using real-time feedback. (Photo courtesy of Ekso Bionics Holdings Inc)

EksoNR, the latest exoskeleton from Ekso Bionics, features EksoView, a new touchscreen controller that allows therapists to intuitively adapt assistance to challenge patients using real-time feedback. (Photo courtesy of Ekso Bionics Holdings Inc)

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The EksoNR is a next-generation EksoGT exoskeleton device developed by Ekso Bionics Holdings Inc to aid the neurorehabilitation of patients recovering from stroke and spinal cord injury, and to help them learn to walk again with a more natural gait.

Among the EksoNR’s new features and enhancements is EksoView, a new touchscreen controller that allows therapists to intuitively adapt assistance to challenge patients using real-time feedback and perform outcome measures during use.

Held in the palm of a therapists’ hand, EksoView provides visualization of various exercises beyond gait training, such as balancing, squatting from sit-to-stand positioning, lifting one leg, or standing in place, to actively engage patients and enhance the use of these beneficial features.

Another feature is the optimized SmartAssist software, developed to enable EksoNR to have a smoother and more natural gait path when transitioning between steps.

SmartAssist also gives gait symmetry and posture feedback and allows therapists to track patient progress with the upgraded EksoPulse, a cloud-based analytics solution. EksoPulse now uses rehabilitation data to generate insightful metrics and graphs for therapists and administrators to monitor patient progress and outcomes, Ekso Bionics notes in a media release.

“Ekso Bionics is committed to developing the latest exoskeleton advances for rehabilitation. We continue to innovate to ensure physical therapists have access to the latest tools to deliver better patient outcomes and superior care in neurorehabilitation,” says Jack Peurach, chief executive officer and president of Ekso Bionics, in the release.

“EksoNR is a full neurorehabilitation tool that is effective, intuitive, and differentiating. There is an increasing demand for adoption, as our technology sets rehabilitation centers apart,” he adds.

EksoNR is cleared by the US Federal Drug Administration for stroke and spinal cord injury rehabilitation. The device is also CE-marked and available in Europe.

Ekso Bionics will begin taking orders for EksoNR immediately. Existing customers will have the option to upgrade, the release continues.

[Source: Ekso Bionics]


via Ekso Bionics Unveils the EksoNR Neurorehabilitation Device – Rehab Managment

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