Electromechanical design for an electrically powered, actively balanced one leg planar robot

Experiments in which actively balanced legged robots perform complex control operations by working in parallel on adequately decomposed tasks have given positive results, but the performance of the prototypes themselves contradicts the essence of the active balance concepts. These concepts aim to ameliorate the power efficiency of the legged systems by use of the systems intrinsic dynamic properties. The reason for this is the utilization of pneumatic and hydraulic actuators for the realisation of the prototypes. These actuators provide high effective power-to-mass ratios, thus facilitating the control task. Yet, the whole system's efficiency (pumps, piping, servovalves, etc) remains poor. The direct implementation of the control concepts in small-scale (e.g. human sized) energy-sufficient systems thus represent a serious engineering problem. The authors propose an electromechanical design for an electrically powered actively balanced one-leg planar machine, capable of operating with an average 48 W power requirement, at a maximum speed of 0.3 m/sec, with 7.5 kg of mass. In order to obtain that, an original mechanical design of an articulated leg and leg attitude control are realised.<>