Considering the unnecessary leg dimension and energy consumption problem caused by the redundancy of the actual motion space of hexapod robot respect to the target workspace, an optimal design of the three joint structured leg with mammalian configuration was raised. The relationship between the target workspace and actual motion space was discussed. Thus, a general optimal mechanism design for the target workspace was proposed through the kinematics analysis of the foot tip. A mathematics model of nonlinear programming with inequality constraints was established, and Augmented Lagrangian Genetic Algorithm was used to find out the globally optimal solution. Through the optimization, the structure dimension and joint rotation scope is dwindled obviously and the redundancy of the motion space is improved, And the results illustrate that the optimization can satisfy the demanding of the actual tasks and is in good manipulability. At last, the joint torque and system energy consumption is analyzed, which verified that with the requirement of turning and obstacle overcome satisfied, the total energy consumption can be reduced through decreasing the joint dimension and inertia．
ZHU Ya-guang, JIN Bo, LI Wei, LI Shi-tong. Optimal design of a hexapod robot leg structure based on target workspace. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(5): 770-776.
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