This paper describes the control system for an eight-degree-of-freedom biped robot built at the University of Salford. The controller enables the robot to walk in the sagittal plane on smooth level terrain and is essentially an observer-based controller utilising state feedback, integral action and feedforward control. The robot posture is controlled by selecting constant reference set points for the control system. Locomotion is achieved by suitably modifying the reference set points. The robot walks with a step length of approximately 0.3 m and a speed of about 0.03 m/s.

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Vol 19, Issue 1, 1997