Abstract
In this article, the author aimed to design a lower limb orthosis for the person whose lower limb can emerge the normal electromyography. According to the motion intention method, using the electromyography signal and upper limb angle as the trigger signals of motion. The lower limb electromyography signal is processed by linear envelope method, and the signal was sent to the controller. The system used PI current feedback control to give the wearer’s knee appropriate aids. This orthosis is an exoskeleton with four flat EC motors as the actuators mounted on the outer of the wearer’s both knees and hips, and using a battery as the power source. While motor rotating, motor sends the torque to wearer’s knee, so that, the wearer will use less force when he/she is sitting down or standing up, and reach the aid purpose.