Driving cable design for a cylindrical deployable mechanism based on depth first search

Abstract

Cables are utilized widely to drive deployable mechanism for the advantages of light weight and wide range of arrangement. This paper proposes a novel driving cable design method based on depth first search, which can achieve the optimal cable route to drive a cylindrical deployable mechanism. A deployable mechanism using Bennett linkages which can approximate a given cylindrical surface is constructed. Kinematic model of the mechanism is established to obtain the position of the links and joints during the deployment and retraction process. Principles of driving cable design, which should be followed in the design of driving cable route, are presented. A driving cable route design method based on depth first search algorithm is proposed to find all possible cable routes. Considering the length of cable and installation of pulleys, an integrated evaluation function is introduced to assess the cable route. The optimal deploying and folding driving cable routes of the cylindrical mechanism are obtained with the proposed method. A prototype is fabricated and experiments are conducted to verify the feasibility of the design. The proposed method can be applied in the driving cable route design of other deployable mechanisms.