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Control device for robot

  • US 8,532,824 B2
  • Filed: 12/27/2010
  • Issued: 09/10/2013
  • Est. Priority Date: 12/28/2009
  • Status: Active Grant
First Claim
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1. A control device for a robot configured to determine a desired driving force to be imparted to each joint of a robot, which has a plurality of links interconnected through joints and actuators which drive the joints, and to control the operation of each of the actuators on the basis of the determined desired driving force in the case where a motion of the robot is effected while causing at least one or more contact portion of the robot to come in contact with an external world of the robot, the control device comprising:

  • a basic parameter group calculating unit which calculates a basic parameter group constituted of an inertia matrix for converting the second-order differential value of a generalized variable vector of the robot, which includes at least the displacement amount of each joint of the robot as a component, into a generalized force vector, and a gravity-dependent generalized force vector value, which is the value of a generalized force vector produced by the gravitational force acting on each link of the robot, or a basic parameter group constituted of the inertia matrix, the gravity-dependent generalized force vector, and a centrifugal force/Coriolis force-dependent generalized force vector value, which is the value of a generalized force vector generated by a centrifugal force and a Coriolis force acting on each link of the robot, on the basis of generalized variable observation information, which includes at least the observed value of an actual displacement amount of each joint of the robot;

    a contact portion Jacobian matrix calculating unit which receives contact state information indicating the contact state of the one or more contact portions and the generalized variable observation information and calculates a contact portion Jacobian matrix, which is a Jacobian matrix expressing a relationship between the motion velocity of a predetermined contact portion representative element set as an element representing the motion of the one or more contact portions in contact with the external world and a first-order differential value of the generalized variable vector on the basis of at least the received contact state information and generalized variable observation information;

    a state amount Jacobian matrix calculating unit which receives the generalized variable observation information and calculates a state amount Jacobian matrix, which is a Jacobian matrix expressing a relationship between a predetermined type of state amount having a value dependent upon the value of the generalized variable vector and the first-order differential value of the generalized variable vector on the basis of at least the received generalized variable observation information;

    a desired driving force determining unit which receives the basic parameter group, the contact portion Jacobian matrix and the state amount Jacobian matrix, which have been calculated, a desired value of a contact portion representative element motion acceleration, which is the desired value of the motion acceleration of the contact portion representative element, the generalized variable observation information, and the desired value of the first-order differential value of the predetermined type of state amount, uses the received data to calculate a component value corresponding to the displacement amount of each joint in a desired generalized force vector τ

    cmd, which is a target of a generalized force vector that satisfies the relationship of expression 01 given below, and determines the calculated component value as a desired driving force to be imparted to the joint; and

    an actuator control unit which controls the operation of the actuator on the basis of at least the determined desired driving force;


    S′

    +(Js*M

    1
    *Tc−

    Js′

    )*q′

    =(Js*M

    1
    *Pc)*(τ

    cmd−

    τ

    cmpn
    ) 



    Expression 01whereq;

    generalized variable vectorq′

    ;

    observed value of first-order differential value of q (=dq/dt)S;

    state amountS′

    ;

    desired value of first-order differential value of S (=dS/dt)M;

    inertia matrixτ

    cmpn;

    vector defined by τ

    cmpn≡

    (N+G)−

    Pc

    1
    *Cc or τ

    cmpn≡

    G−

    Pc

    1
    *CcG;

    gravity-dependent generalized force vector valueN;

    centrifugal force/Coriolis force-dependent generalized force vector valuePc;

    matrix defined by Pc≡

    I−

    JcT*(Jc#)T I;

    unit matrixJc;

    contact portion Jacobian matrixJc#;

    matrix defined by Jc#≡

    (M

    1
    )T*JcT*RcT Rc;

    matrix defined by Rc≡

    ((Jc*M

    1
    *JcT)

    1
    )T Cc;

    vector defined by Cc≡



    JcT*Rc*CC;

    desired value of contact portion representative element motion acceleration (scalar or vector)Tc;

    matrix defined by Tc≡



    JcT*Rc*Jc′

    Jc′

    ;

    matrix obtained by subjecting Jc to first-order differentiation (=dJc/dt)Js;

    state amount Jacobian matrixJs′

    ;

    matrix obtained by subjecting Js to first-order differentiation (=dJs/dt).

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