Optimal Driving Forces Distribution for a Six-parallel-legged Robot Based on Dual Quadratic Programming Method

doi:10.3901/JME.2018.07.020

Abstract

Abstract: The active forces distribution algorithm for improving bearing capability and minimizing energy consumption is proposed to solve the redundant actuation problem of a six-parallel-legged robot. The transformation between active joint forces and foot contact forces is established based on the kinematic model and dynamic model. After analyzing the force/moment equilibrium equations of the robot, the quadratic programming optimization model is obtained considering the constraints of friction cone, unilateral constraint and the limits of motors' torques. The solving time of the quadratic programming is reduced by eliminating and simplifying equality and inequality constraints using elimination method based on QR decomposition and dual method. The difference between the objective function of multi-legged robots and multi-finger hands is pointed out because of the difference of their dynamic models. Compared with the traditional method, the proposed algorithm has great advantages in improving bearing capability and minimizing energy consumption due to the efficient utilizing of the contact friction forces.

Key words: dual method, force distribution, quadratic programming, six-parallel-legged robot

CLC Number:

TP242

XIN Guiyang, ZHONG Guoliang, WANG Hengsheng, DENG Hua. Optimal Driving Forces Distribution for a Six-parallel-legged Robot Based on Dual Quadratic Programming Method[J]. Journal of Mechanical Engineering, 2018, 54(7): 20-27.

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