Collision-free shape control of a plane tensegrity structure using an incremental dynamic relaxation method and a trial-and-error process

Abstract

The application of tensegrity structures has been extended to deployable structures, smart structures, and robots. In these applications, large displacement shape control is usually involved. The problem of finding a collision-free path for the shape control emerges. In this article, a preliminary study on the collision-free shape control of tensegrity structures is carried out based on a representative two-dimensional tensegrity system. An incremental procedure based on dynamic relaxation method is proposed to track the trajectory of the movement during shape control. For every increment along the trajectory, collision is checked by a method based on geometrical analysis. The effect of the size of the obstacle to the number of feasible paths is investigated. It is found that when the size of the obstacle reaches a critical value, the structure is no longer able to move to the target configuration by a single step. As a result, a relay point is added in the free space. Via the relay point, free paths connecting the initial configuration and the target configuration are found.

Keywords

Tensegrity shape control collision check path plan

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