Patent ID: 8112179
Filing Date: 2012-02-07
Classification: B25J,G05B

Abstract:
1. A multi-joint robot having a multi-joint robot mechanism and a controller, wherein: the multi-joint robot mechanism includes plural links, plural joints, and plural actuators, wherein adjacent links are connected by a joint and each of the actuators drives a respective joint, whereby the robot is capable of varying the state of an end link; and the controller includes: a storage unit that stores a target state vector of the end link and a priority set to each component of the target state vector; a load estimate unit that estimates a magnitude and a direction of a load acting on a drive axis of each joint; an overloaded joint specifying unit that specifies an overloaded joint of which the estimated magnitude of the load is greater than a threshold and a non-overloaded joint of which the estimated magnitude of the load is not greater than the threshold; a first drive quantity calculating unit that calculates a target drive quantity for driving the overloaded joint in the same direction as the direction of the load acting on the overloaded joint; a second drive quantity calculating unit that extracts the same number of components as that of the non-overloaded joints from the components of the target state vector in the order of having higher priority, and calculates target drive quantities for driving the non-overloaded joints so as to realize the values of the extracted components; and a driver that controls the actuators based on the target drive quantities calculated by the first drive quantity calculating unit and the second drive quantity calculating unit.