UPWARD JUMP OF A BIPED

Abstract

This paper explores the vertical upward jumping of a planar biped. There are two stance phases and one flight phase in the jump. One stance phase takes place before the flight phase, another one after the flight phase. The stance phase before the flight phase is decomposed into several parts: A crouching, a thrust at the knees, a rotation of both feet (massless) around their toes. The second stance phase (after the flight phase) starts with a touchdown of the toes. It consists of a feet rotation, a touchdown of the whole soles and finally of a straightening up movement of the biped. A mathematical model for this kind of jump is developed. Torques are applied at the hip, knee and ankle joints. The control algorithm is designed to ensure the jump of the biped. The synthesis of the jumping process is supported by simulation, which gives consistent results with human data from biomechanical literature. The stick diagram of the jump derived from simulation results seems natural for the human jumping.