Torque distribution in a six-legged robot

Erden M. S. , Leblebicioglu K.

IEEE TRANSACTIONS ON ROBOTICS, vol.23, no.1, pp.179-186, 2007 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23 Issue: 1
  • Publication Date: 2007
  • Doi Number: 10.1109/tro.2006.886276
  • Page Numbers: pp.179-186
  • Keywords: force distribution, legged locomotion, robot dynamics, six-legged robot, torque distribution, FORCE DISTRIBUTION EQUATIONS, EFFICIENT FORMULATION, OPTIMIZATION, LOCOMOTION


In this paper, distribution of required forces and moments to the supporting legs of a six-legged robot is handled as a torque-distribution problem. This approach is comparatively contrasted to the conventional approach of tip-point force distribution. The formulation of dynamics is performed by using the joint torques as the primary variables. The sum of the squares of the joint torques on the supporting legs is considered to be proportional to the dissipated power. The objective function is constructed as this sum, and the problem is formulated as to minimize this quadratic objective function with respect to linear equality and inequality constraints. It is demonstrated that the torque-distribution scheme results in a much more efficient distribution compared with the conventional scheme of force distribution. In contrast to the force distribution, the torque-distribution scheme makes good use of interaction forces and friction in order to minimize the required joint torques.