Armin stands straight out the window in front of the open-plan office. The sturdy, green-silver machine with a long, articulated gripper arm seems to come from a factory for assembling cars. But it is located in a multi-storey research building opposite Insel Hospital Bern. A few years ago, Armin developed ETH Zurich by Robert Riener and Tobias Nef to train the hand and arm movements of patients with post-stroke paralysis. Now the 39-year-old professor at the University of Berne's Competence Center for Biomedical Engineering (Artorg) is working on tailoring robot rehabilitation to individual needs.
Every year, nearly 16,000 people in Switzerland suffer. Survivors of such cerebral infarction often argue over the ongoing failure of the motor system. Globally, the disease is one of the most common causes of paralysis. Intensive physical and occupational activities can often restore a lot of flexibility. However, such treatment is usually very time consuming and time consuming. Because patients must be supported or guided to regain grip and walk again.
"The longer the patient is inactive, the harder it is for him to recover mobility," says Marchal-Crespo. It is also important to repeat exercises continuously so that the structures of the brain can regenerate themselves. However, rehabilitation robots have never been intended as a replacement for conventional therapies, but rather as a useful supplement. People and machines with the help of robot and virtual reality. He was especially interested in helping paralytic people after a stroke. Prior to ETH he studied and obtained his doctorate at the University of California at Irvine. In 201
"We improve the ability to move by reinforcing faults," says the engineer. It would be weird. However, if a stroke patient, for example, wants to take something, but is inaccurate, the rehab robot reinforces this inaccuracy by creating a slight objection. In this way, the patient has to work harder. The learning algorithm developed by Marchal-Crespo independently determines which patient complicates the task and which makes it easier.
In training, the robot decides whether to assist or prevent it. Photo: Adrian Moser
In addition to Armin, there is also a horizontal walking machine in Bern's open-plan office. Marchal-Crespo can then assess a patient even during exercise on a magnetic resonance tomograph. He lied, actively or actively moved his legs there with a knee-jerk robot. Researchers want to know which areas of the brain are stimulated by such specific exercises and how neurons reconnect after a stroke. He is currently trying to mimic the feeling of walking as low as he can, so that the pressure on the feet is felt.
He originally came from the suburbs of Barcelona, so to speak, laughing. He was fortunate that he received a scholar for the USA at that time. Because his parents were not academic, and his father made money as a taxi driver. Her mother has always supported her and her two sisters in every way, she added. One is now a mechanical engineer in Australia, the other a chemist in Barcelona.
Since the man of Marchal-Crespo also came from the capital of Catalonia, he speaks Catalan to three children aged three to seven as he speaks Spanish to them. Daily life with family and work is a challenge, but also exciting and a privilege, he finds. Her husband works as an engineer at ABB in Zurich. While the family lives there, he talks to Bern four days a week. "Whenever possible, we will all be doing outdoor activities over the weekend and either walking or biking." also fascinated by the sheer possibilities of the virtual world. So one of his doctoral students is now releasing a glass of VR. If you open it, you are in a virtual room where suddenly there is an apple, then a pear or other apple hangs in the air. In a controller you will need to control a ball exactly with these fruits and at the same time count the fruits.
"It looks very light," says the scientist. But for patients after a stroke, the combination of motor activity and a cognitive task is difficult. Because they need to focus on both, and only recover these capabilities. For example, a special joystick that allows you to drive a small ball to different rough, smooth, soft, soft, hilly or like canyon surfaces and feel the specific material in hand that you hold only in the virtual world. "We try to be as active as possible in order to achieve the greatest possible success in training," he said.
Its purpose is to encourage patients to exercise longer and more intensively. Of course, this is exhausting and often frustrating, he emphasizes. When a child learns to walk, drop it, but get up again, try again and again. But it comes from the inner drive. Those who have to practice walking again after a stroke will need more strength and endurance.
He is currently investigating whether he can increase patient motivation in special games. "I also want to make the training sessions exciting," the researcher said.
Created: 09.11.2019, 21:04