Flexible Robotic Arms Under Multiple Driving Methods and Their Application Environments

This paper focuses on the field of flexible robotic arms, systematically analyzing the principles, advantages, and disadvantages of five driving methods: rope-driven, shape memory alloy-driven, and pneumatic-driven. Pneumatic drive uses compressed air as power, with a simple structure, good compliance, and safe human-machine interaction, but it has limited output force and insufficient control precision. Hydraulic drive relies on liquid pressure transmission, providing high drive force, control accuracy, and stability, yet it suffers from complex systems, leakage risks, and heavy equipment. Shape memory alloys drive through material deformation, offering compact structure and good concealment, but with low energy conversion efficiency and limited driving stroke. A cable-driven system uses cable stretching and slack to transmit the motion, which allows use over distance and a large range of motion, however, elastic actuation and slack may affect accuracy. The needs in the medical, industrial, deep-sea exploration and home service applications of the driving methods are also mentioned in the paper and the flexibility of each driving approach elucidated. The findings can bring references to the rational use of the flexible robotic arm and these designs can be used to promote the technological development.