Can an underactuated leg with a passive spring at the knee achieve a ballistic step?

Abstract

Abstract:In this paper, we present the design and the results of a control scheme aimed at moving an underactuated double pendulum simulating a leg. The system is actuated at the hip and includes a spring at the knee. It interacts with the grou nd, which is in fact a treadmill, through a telescopic foot made of a linear spri ng and a damper. The control scheme is different in the 2 phases, swing and stance, and a repetitive step is achieved by switching between these two controls. The paper describes the used models, the control algorithms and their implementation. It pr esents also experimental results of the approach. Key-words: