Wearable Robot Helps Paralytic People Walk

Scientists have designed a wearable lower limb robot exoskeleton with natural knee movement to help stroke and spinal cord injury patients regain the ability to walk and strengthen their muscles. Wearable “robot-assisted training” is quickly emerging as a method to improve gait rehabilitation. Researchers from Beihang University in China and Aalborg University in Denmark said that the robotic exoskeleton was intended to help stroke patients strengthen their physical fitness, aid the rehabilitation training of paralyzed patients, or to assist those who need help performing daily activities. The team focused on the knee joint, one of the most complex mechanical systems within the human body and a critical player during gait. The knee joint’s motion is actuated by several skeletal muscles along its articular surfaces and its centre of rotation moves. Researchers wondered if a parallel mechanism similar to skeletal muscles would be useful for designing a bionic knee joint. This design features a parallel knee joint to improve the bio-imitability and adaptability of the exoskeleton. The exoskeleton taps a hybrid serial parallel kinematic structure consisting of a one degree of freedom (DOF) hip joint module and a 2-DOF knee joint module in the sagittal plane. A planar 2-DOF parallel mechanism helps to fully accommodate the motion of the human knee – enabling rotation and relative sliding. When wearing the exoskeleton, its movement should be synchronized and consistent with a patient’s natural movement.