The design and control of Scout I, a simple quadruped robot /

Abstract

A new type of quadruped robot has been developed, the Scout class. Each leg utilizes only one actuated degree of freedom (as opposed to a typical three) to reduce complexity and cost. The design of the first of these robots, Scout I is presented. In modelling Scout, impacts are assumed instantaneous with angular momentum being conserved about the impacting toe. Stance phases are modelled as a double inverted pendulum with one input and a pin joint with the ground. Walking controllers requiring a minimum of sensing are then developed and examined both in simulation and experiments. Small errors in impact modelling coupled with high setpoint sensitivity are found to result in discrepancies. However, despite this stable open loop walking is achieved in all cases examined. Additional behaviors for Scout are presented, including turning, side stepping, sitting and laying down, and step and stair climbing.