Patent ID: 7324872

Claim:
An external force estimation system for estimating an external force acting upon a robot apparatus which includes a machine body which in turn includes a plurality of movable joints, comprising: distribution type contacting state detection means configured to detect a contacting state of an arbitrary portion of said machine body with the external world; actuator current state measurement means configured to measure a position, a speed and a generation force at present of each of said joint actuators; motion state measurement means configured to measure an acceleration and an angular speed at least at one portion of said machine body; motion equation setting means configured to set a motion equation of said robot apparatus; known term calculation means configured to calculate a known term of the motion equation from the current states of said joint actuators obtained from said actuator current state measurement means and the current state of said robot apparatus obtained from said motion state measurement means; and external force estimation means configured to estimate an acting state of the external force as an unknown term of the motion equation.