Educational semi-passive biped walking system

The study of biped walking robots present various challenges because of the complexity of the dynamics of their motion and for the access to experimental work since most walking robots are expensive. This article presents the development of an actuated biped passive walking system adequate to support the learning of basic concepts of walking robots. The development progressively includes dynamical models with rising complexity adequate for testing in an easy to built physical prototype. The system initiates with a simple passive walking device which progresses with the addition of an actuator to excite its natural motion. The analysis of this mode of actuation is presented and a controller to maintain the gait given irregularities in the ground is proposed. As a last phase, the design of a knee mechanism with a blocking system is described. The system has been used for modelling and simulation of gait dynamics, state estimation and control of gait frequency.