ROBOT WITH JOINTS OF VARIABLE RIGIDITY AND METHOD FOR CALCULATING SAID OPTIMIZED RIGIDITY

摘要

A jointed robot capable to move on a surface is provided. It is known to limit to a predefined fixed value the torque that the motors of the joints of the robot can develop. A rigidity coefficient corresponding to the limit torque is calculated by solving a dynamic equilibrium model of the robot. The contact points of the characteristic effectors are determined by a selection from a list of potential effectors, notably as a function of a criterion of distance from a virtual ground plane. The contact forces for said effectors are calculated by optimal resolution of the equilibrium equations. Finally the torques applied in the dynamic equilibrium model of the robot and the coefficients of corresponding rigidity are calculated.

主权项

1. A robot with capabilities of displacement on at least one jointed chain comprising at least one sensor of contact of the end of said chain with the displacement surface, said chain comprising at least one joint, said joint driven by an electric motor controlled by an order determined based on position and/or velocity and by means for limiting the current and/or the torque applied to said motor, wherein said limiting means are controlled as a function of the torque applied to said at least one joint, said torque being calculated as a solution of an equation modeling the dynamic equilibrium of the robot between, on the one hand, the sum of the difference of the inertial forces due to the angular acceleration of the joint and of the gravitational acceleration and of the effect of the Coriolis and centrifugal forces and, on the other hand, the sum of the torque and of the contact, friction and perturbation forces, said torque and force being applied to said joint, a part of the effects of the inertial forces due to the angular acceleration of the joint, of the Coriolis and centrifugal forces and of the friction forces being modeled by an offset.