Of exoskeletons and service robots – the future of rehabilitation

For most people, enjoying a good quality of life means having the ability to move freely, safely and independently. Intensive and costly rehabilitation is needed if this is no longer an option after a stroke for example. We are introducing some projects that deliver innovative robotic solutions.

As part of the RoSylerNT project, the Institute of Biomechanics and Orthopedics at the German Sport University Cologne develops robotic training systems for physical and cognitive stimulation. The idea is to not just apply the devices in rehabilitation, but to also use them to promote disease prevention.

KUKA Deutschland GmbH provides a robotic arm for the project, which works as a strength training machine that is able to create resistance in all directions. The device features different types of handles, levers, plates and sensor technology users must move. Learning algorithms collect data pertaining to the patient's physical capacity and strength and adjust the device accordingly. This allows the patient to train under optimal conditions. Real-time diagnostics protects against overload and overstress even in unexpected situations. This allows the system to adapt to the needs and capabilities of older adults or severely impaired patients. The goal is to have an interactive training partner that identifies the user’s posture, movement, and strain and responds accordingly.

The RWTH Aachen University also uses a KUKA robot as part of its inRehaRob project (click here for the video report about inRehaRob on REHACARE.com). The robot guides the patient's forearm in this particular scenario. The system is designed to enable stroke patients to perform exercise repetitions independently and subsequently reinforce the efficiency of the therapy and solidify long-term recovery. DIERS International GmbH is responsible for the human-machine interface that allows intuitive interaction. Sensors made by EvoSense Development GmbH capture and analyze the movements and muscle activation levels. This technology resembles the innovative end effector-based approach, where the robot merely guides the distal end of the arm - the hand - while the patient independently performs the movements of the proximal joints - shoulder and elbow motions.

Until early 2018, the Recupera REHA project by the German Research Center for Artificial Intelligence (DFKI) developed a mobile whole-body exoskeleton and an active independent subsystem unit to support robot-assisted neurological rehabilitation. The exoskeleton is self-supporting and designed to capture nearly the entire range of motion of the human body whereas the subsystem is attached to a wheelchair and mimics the kinematics of the human arm, thus supporting the patient in performing daily living activities. The mechatronic approaches were combined with a new system to analyze EEG and EMG signals online. This allows an assessment of the patient's condition and status and facilitates a multi-level control structure of the exoskeleton.

The system has three modes of control: In the first mode, the movement of one arm allows the other arm to move in synchrony. This offers both visual and proprioceptive stimulation, which also improves body awareness. The second mode performs the movement that was indicated by a third person – the therapist for example. Movements can subsequently be repeated multiple times, promoting relearning. In the third mode, the exoskeleton can be controlled using the patient's still limited muscle activity. This is done by measuring EMG signals, from which the system infers the patient's movement intention, allowing it to offer intuitive support. The project leaders plan to enhance the exoskeletons in the future and make them even more lightweight and flexible. The Research Center has teamed up with rehaworks GmbH for this project.

Motor skill recovery is not the only purpose of rehabilitation and the use of robotics. Post-stroke rehabilitation also includes self-training programs for patients. Not only does this make economic sense because it doesn't require as much staff involvement, but it also has a therapeutic effect. Self-guided running helps patients to gradually recover their independence. Patients often don't feel confident to train without a therapist by their side, or they are scared they might lose their bearings and balance. ROREAS is an interactive robotic rehabilitation assistant designed to help stroke patients recover their walking and spatial orientation skills. The device was developed as part of a project by the Technical University Ilmenau and MetraLabs GmbH and was clinically tested until 2016 at the m & i-Fachklinik Bad Liebenstein.

This talking service robot meets patients at their room, stays behind the patient during gait training exercises, points the way, gives simple instructions and indicates seating options for resting. The robot measures training times and gait performance, making progress palpable and boosting motivation. Over the course of the rehabilitation process, the device gradually provides less guidance and merely follows the patient. The robot supports patients with self-guided training designed to help them recover and live a self-determined life as soon as possible. The clinical trial results confirm that ROREAS motivates patients to increase their training time and progressively walk longer distances.

Apart from their primary medical condition, patients in intensive care units frequently suffer from circulation issues and muscle weakness thanks to being bedridden for an extended amount of time. This slows down their rehabilitation and recovery process, which is also why regular and early mobilization should always be an integral part of intensive care interventions. Unfortunately, in reality there is never enough time and available staff to address this need.

Led by the Schön Klinik Bad Aibling, the MobIPaR project (Mobilization of Intensive Care Patients via Adaptive Robotics) aims to develop a robotic assistance system to offer mobility support for intensive care patients in vertically adjustable hospital beds. The project goal is to promote the recovery process of critically ill patients during the different stages and environments. Early mobilization benefits patients by supporting physiological systems and reducing secondary complications. It also provides physical support to caregivers, therapist and family members. Technical research and development are aided by the Reactive Robotics GmbH in cooperation with faculties of several German universities.

Each of these solutions includes robotic technology that's intended to be a resource for trained staff.  The overarching goal of all projects is to use robotics to help reduce the physical burden of therapists and caregivers and free up time. In the long-term, this will bridge the skills gap, meet the ever-increasing need for rehabilitation services and, ultimately, improve the quality and efficiency of the overall health care system.