Design and analysis of rope driven joint for upper limb rehabilitation robot
1. School of Agricultural Equipment Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2. State Key Laboratory of Robotics, Shenyang Institute of Automation CAS, Shenyang, Liaoning 110016, China
Abstract：To solve the problems of easy slippage by elasticity and easy accumulation of errors in rope driving, a generalized driving method of "rope+toothed belt" was proposed to convert the traditional rigid power transmission of motor plus gear and reducer into flexible transmission. The pull force of wire rope was calculated, and the friction coefficient between wire rope and outer hose was analyzed by the friction compensation method to obtain the relationship between friction force of steel wire rope and load. The combination of the same steel wire rope and the rope jacket was tested for different bending degrees. The length of steel wire rope in the hose was changed, and the load was applied at the end. The steel wire rope was installed on the fixing plate, and the size of wire rope was determined by measuring the pulling force and the friction force. The ADAMS was used to simulate the wire ropes of rope-driven joints. The results show that the influence of bending degree on the friction force of steel wire rope is negligible, and the friction force of steel wire rope is proportional to the length and load. The correctness of the theoretical analysis is verified by the simulation. The maximum tight edge pressure of rope is 8 N, and the actual friction force is 7.6 N. The 304 stainless steel is adopted for wire rope with the diameter of 1.5 mm and the maximum load of 25 kg.
2018, Vol. 39 
