Rehabilitation robotics are robotic devices that help a patient recover movement, such as walking or using an arm, after a stroke, a spinal injury or an operation. They are used beside other physiotherapy machines in rehabilitation centres, such as electrotherapy and therapeutic ultrasound devices. Rehabilitation means the treatment that helps a person get back abilities they have lost.
Recovery after a stroke depends on practice. The brain relearns a movement by repeating it hundreds or thousands of times. A physiotherapist can move a patient's leg by hand, but only for a limited time before tiring. A robot can repeat the movement for a whole session, in the same way each time, and measure every repetition.
There are two common kinds. A gait trainer helps with walking. The patient wears a harness that takes part of the body's weight, over a treadmill. Robotic leg braces move the hips and knees through each step. An upper-limb robot helps with the shoulder, elbow, wrist or fingers. The patient moves a handle or wears a glove, while a game on a screen sets targets to reach.
The key software idea is called assist-as-needed. Sensors in the robot measure how much force the patient produces. The robot adds only the force that the patient cannot yet produce. As the patient recovers, the robot does less of the work. Each session is recorded: the number of steps or movements, the range of movement of each joint, and how much help the robot gave.
Imagine a 45-year-old shopkeeper in Kozhikode who cannot move his left leg well after a stroke. Three times a week, he walks for 30 minutes on a gait trainer, about 600 steps in each session. In the first week, the robot provides about 80% of the force needed for each step. By the fourth week, it provides 55%. The physiotherapist sees this trend on the session report, and slowly reduces the robot's help. The reports are added to his hospital EHR.
Robots are expensive, so they are used mainly in hospitals and rehabilitation centres. Some makers now design and build them in India, at a lower cost. After the patient goes home, the exercises can continue through digital physiotherapy apps.
A rehabilitation robot's motors and sensors are similar to those in an industrial robot. But this robot moves a human body. So it must limit its force, and stop at once if the patient's limb resists. That requirement is part of its safety certification.