Kinematics-based estimation of contact constraints using only proprioception

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Colleges, School and Institutes

External organisations

  • National Nuclear Laboratory Ltd.


Robots are increasingly being required to perform tasks which involve contacts with the environment. This paper addresses the problem of estimating environmental constraints on the robot's motion. We present a method which estimates such constraints, by computing the null space of a set of velocity vectors which differ from commanded velocities during contacts. We further extend this method to handle unilateral constraints, for example when the robot touches a rigid surface. Unlike previous work, our method is based on kinematics analysis, using only proprioceptive joint encoders, thus there is no need for either expensive force-torque sensors or tactile sensors at the contact points or any use of vision. We first show results of experiments with a simulated robot in a variety of situations, and we analyse the effect of various levels of observation noise on the resulting contact estimates. Finally we evaluate the performance of our method on two sets of experiments using a KUKA LWR IV manipulator, tasked with exploring and estimating the constraints caused by a horizontal surface and an inclined surface.


Original languageEnglish
Title of host publicationProceedings of the 2016 IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids 2016)
Publication statusPublished - 2 Jan 2017
Event2016 IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids) - The Westin Resort & Spa, Cancun, Mexico
Duration: 15 Nov 201617 Nov 2016

Publication series

NameIEEE-RAS International Conference on Humanoid Robots
ISSN (Electronic)2164-0580


Conference2016 IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids)
Internet address