A multi-DOF robotic exoskeleton interface for hand motion assistance

This paper outlines the design and development of a robotic exoskeleton based rehabilitation system. A portable direct-driven optimized hand exoskeleton system has been proposed. The optimization procedure primarily based on matching the exoskeleton and finger workspaces guided the system design. The selection of actuators for the proposed system has emerged as a result of experiments with users of different hand sizes. Using commercial sensors, various hand parameters, e.g. maximum and average force levels have been measured. The results of these experiments have been mapped directly to the mechanical design of the system. An under-actuated optimum mechanism has been analysed followed by the design and realization of the first prototype. The system provides both position and force feedback sensory information which can improve the outcomes of a professional rehabilitation exercise. © 2011 IEEE

Controlling a knee CPM machine using PID and iterative learning control algorithm

A conventional continuous passive motion (CPM) machine uses simple controller such as On/Off controller. Some better CPMs use PID controller. These kind of CPMs can not distinguish load different due to the different size of the patient leg. This may cause the CPM no longer follow the trajectory or the angle commands. Meanwhile, each patient may have different scenario of therapy from the others. When progress on the patient exists, the range of the flexion may be increased step by step. Therefore, the treatment can be different in term of the range of flexion from time to time. This paper proposes CPM with hybrid proportional integral derivative (PID) and iterative learning controller (ILC). The system has capability in learning the trajectory tracking. Therefore, the CPM will be able to follow any load or trajectory changes applied to it. The more accurate CPM machine can follow the trajectory command, the better its performance for the treatment. The experiment showed that the system was stable due to the PID controller. The tracking performance also improved with the ILC even there exist some disturbances

DESIGN AND DEVELOPMENT OF 3D PRINTED MYOELECTRIC ROBOTIC EXOSKELETON FOR HAND REHABILITATION

The development of dynamic rehabilitation devices can be evaluated as a research fast-growing field. Indeed, robot-assisted therapy is an advanced new technology mainly in stroke rehabilitation. Although patients benefit from this enormous development of technology, including the presence of rehabilitation robots, the therapeutic field still suffering a lack in hand robotic rehabilitation devices. In this context, this work proposes a new design of a 3D printed hand exoskeleton for the stroke rehabilitation. Based on the EMG signals measured from the muscles responsible for the hand motion, the designed mechatronic system detects the intention of hand opening or hand closing from the stroked subject. Based on an embedded controller and five servomotors, the low cost robotic system is able to drive in real time three degrees of freedom (DOFs) for each finger. The real tests with stroked subjects showed that the designed hand exoskeleton architecture has a positive effect on the motion finger range and mainly in the hand ability to perform some simple tasks. The case studies showed a good recovery of the motor functions and consequently the developed system efficiency

Development of a novel robotic system for hand rehabilitation

Rehabilitation Robotics involves the use of robotic systems as an enabling technology for people with kinetic problems, in order to help them recover from a physical trauma. This paper presents the investigation of a robotic system for stroke and post hand-surgery patient rehabilitation, in order to gradually regain flexibility in their finger-joints by passively extending and flexing their fingers. It includes one linear actuator for each finger and a thin-film force sensor at each fingertip as a safety measure against overstraining the finger-joints. Prior to designing the system, kinematic and dynamic models of a human hand have been derived and simulated in MATLAB. Data obtained from this model show a strong correlation to natural human hand movements, recorded in this study using a 6 DoF motion capture system. Design of the robotic system is performed using UGS NX6 software. © 2011 IEEE

Development of a Wearable Mechatronic Elbow Brace for Postoperative Motion Rehabilitation

This thesis describes the development of a wearable mechatronic brace for upper limb rehabilitation that can be used at any stage of motion training after surgical reconstruction of brachial plexus nerves. The results of the mechanical design and the work completed towards finding the best torque transmission system are presented herein. As part of this mechatronic system, a customized control system was designed, tested and modified. The control strategy was improved by replacing a PID controller with a cascade controller. Although the experiments have shown that the proposed device can be successfully used for muscle training, further assessment of the device, with the help of data from the patients with brachial plexus injury (BPI), is required to improve the control strategy. Unique features of this device include the combination of adjustability and modularity, as well as the passive adjustment required to compensate for the carrying angle

Development and Control of a 3-DoF Exoskeleton Robot for Forearm and Wrist Rehabilitation

The research conducted under this project directly contributes to the development of a forearm and wrist rehabilitation robot (UWM-FWRR). Upper extremity impairment following stroke, trauma, sports injuries, occupational injuries, spinal cord injuries, and orthopaedic injuries results in significant deficits in hand manipulation and the performance of everyday tasks. Strokes affect nearly 800,000 people in the United States each year. Rehabilitation programs are the main method of promoting functional recovery in individuals with finger impairment. The conventional therapeutic approach requiring a long commitment by both the clinician and the patient. Robotic devices (RDs) are novel and rapidly expanding technologies in hand rehabilitation. However, existing RDs have not been able to fully restore hand functionality as they cannot provide the independent joint control and levels of velocity and torque required. Our customer discovery [1] reveals that therapists often prescribe therapeutic devices for passive arm/leg movement assistance but no therapeutic devices exist for combined hand, wrist, and forearm movements that can be used at home/clinic. Regaining hand strength and mobility plays an important role in supporting essential activities of daily living, such as eating, and thus has the potential to improve the physical and mental status of both stroke patients and their family caregivers. Therefore, through this research author has develop UWM-FWRR that can provide rehabilitative exercises for forearm and, wrist movements. In contrast to existing RDs, developed UWM-FWRR is a portable, light weight, low cost, and novel powered rehabilitation device that will be developed to provide therapeutic exercises to a wide group of patients with different degrees of impairments. This innovation provides an opportunity for the patients to perform exercises not only with the guidance of a therapist at clinic but also be used at home as a telerehabilitation device through smartphone application (Future works)

A New 4-DOF Robot for Rehabilitation of Knee and Ankle-Foot Complex: Simulation and Experiment

Stationary robotic trainers are lower limb rehab robots which often incorporate an exoskeleton attached to a stationary base. The issue observed in the stationery trainers for simultaneous knee and ankle-foot complex joints is that they restrict the natural motion of ankle-foot in the rehab trainings due to the insufficient Degrees of Freedom (DOFs) of these trainers. A new stationary knee-ankle-foot rehab robot with all necessary DOFs is developed here. A typical rehab training is first implemented in simulation, and then tested on a healthy subject. Results show that the proposed system functions naturally and meets the requirements of the desired rehab training.Comment: 23 pages, 14 figure

State-of-the-Art of Hand Exoskeleton Systems

This paper deals with the analysis of the state-of-the-art of robotic hand exoskeletons (updated at May 2011), which is intended as the first step of a designing activity. A large number of hand exoskeletons (both products and prototypes) that feature some common characteristics and many special peculiarities are reported in the literature. Indeed, in spite of very similar functionalities, different hand exoskeletons can be extremely different for the characteristics of their mechanism architectures, control systems and working principles. The aim of this paper is to provide the reader with a complete and schematic picture of the state-of-the-art of hand exoskeletons. The focus is placed on the description of the main aspects that are involved in the exoskeleton design such as the system kinematics, the actuator systems, the transmission parts and the control schemes. Additionally, the critical issues provided by the literature analysis are discussed in order to enlighten the differences and the common features of different practical solutions. This paper may help to understand both the reasons why certain solutions are proposed for the different applications and the advantages and drawbacks of the different designs proposed in the literature. The motivation of this study is the need to design a new hand exoskeleton for rehabilitation purposes