Search International and National Patent Collections

1. (WO2018219952) COLLISION HANDLING BY A ROBOT

Pub. No.:    WO/2018/219952    International Application No.:    PCT/EP2018/064075
Publication Date: Fri Dec 07 00:59:59 CET 2018 International Filing Date: Wed May 30 01:59:59 CEST 2018
IPC: B25J 9/16
Applicants: FRANKA EMIKA GMBH
Inventors:
Title: COLLISION HANDLING BY A ROBOT
Abstract:
The invention relates to a method for collision handling for a robot (1) with a kinematic chain structure comprising at least one kinematic chain, wherein the kinematic chain structure comprises: a base, links, joints connecting the links, actuators and at least one end-effector, a sensor Sdistal.i. in the most distal link of at least one of the kinematic chains for measuring/estimating force/torque, and sensors Si, for measuring/estimating proprioceptive data, wherein the sensors Si, are arbitrarily positioned along the kinematic chain structure, the method comprising the steps of: provide (SI) a model describing the dynamics of the robot (1), measure and/or estimate (S2) with sensor Sdistal.i force/torque Fext S,distal,i in the most distal link of at least one of the kinematic chains, - measure and/or estimate (S3) with the sensors Si, proprioceptive data: base and robot generalized coordinates q (t) and their time derivative (I), generalized joint motor forces (II), external forces Fs, a base orientation φB(t) and a base velocity (III), generate (S4) an estimate (IV) of the generalized external forces (V) with a momentum observer (3) based on at least one of the proprioceptive data and the model, generate (S5) an estimate (VI) of a second derivative of base and robot generalized coordinates (VII), based on (VIII) and (II), estimate (S6) a Cartesian acceleration (IX) of point D on the kinematic chain structure based on (VI), compensate (S7) the external forces Fs for rigid body dynamics effects based on (IX) and for gravity effects to obtain an estimated external wrench (X), compensate (S8) (IV) for the Jacobian (XI); transformed Fext S.distal.i to obtain an estimation (XII) col of generalized joint forces originating from unexpected collisions, detect (S9) a collision based on given thresholds (XIII)