Bin Li, Wenjuan Du, Cong Wang, Wenyuan Liu, and Liangquan Zhang
Mechanism, Motion Control System, Tensegrity Robots
The 6-strut tensegrity robot(TR-6) consists of 6 discrete rigid struts and 24 continuously elastic cables. The TR-6 can roll, crawl or even jump by self-deformations. As the self-weight impacts the stability and deformability of the TR-6, light-weight mechanism design is required, and most of the existing TR-6 are driven by Pneumatic Muscle Actuators. However, the external air supply and the tubes limit the mobility. Electric prototypes solve the problem above, yet they have to sacrifices the controllability by reducing the number of actuators to lower the self-weight.
In this paper, an all actuated electric prototype is designed and three questions in the design of mechanism and motion control system are solved. Firstly, the internal batteries and motors increase the self-weight and requires greater driving torque. Servo motors are used to replace the DC motors for higher torque-weight ratio. Secondly, wireless modules are mounted on the independent struts to communicate between the discrete electric devices. Thirdly, the ratio of the elastic and nonelastic part of the cables and the elastic coefficient of the cables is taken into consideration to guarantee both the deformability and stability.