Design and control of an under-actuated robot leg, using state feedback and impulse shaping

This paper is about a novel type mono-pedal robot with a bi-articular spring and a mono-articular electric motor. The mechanism is designed based on the concept of the mono-bi configuration, which effectively reduces the number of actuators and consequently the cost, keeping the advantages of bi-articular actuators such as high compliance, stability, accuracy, and homogeneity of motion. By showing the control strategies of JUMPBiE, it shows the feasibility of the proposed system configuration and gives insights on the under-actuated bi-articular actuation problems. In this work, the background of the robot design and its mathematical model were elaborated, and the simulation results were shown and discussed.