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Pulling Open Doors and Drawers: Coordinating an Omni-directional Base and a Compliant Arm with Equilibrium Point Control

Video

May 2010

Publication

Abstract

Previously, we have presented an implementation of impedance control inspired by the Equilibrium Point Hypothesis that we refer to as equilibrium point control (EPC). We have demonstrated that EPC can enable a robot in a fixed position to robustly pull open a variety of doors and drawers, and infer their kinematics without detailed prior models.

In this paper, we extend this framework to support autonomous motion of the robot's omni-directional base both before and during pulling. With our new methods, we show that the robot can autonomously approach and open doors and drawers for which only the location and orientation of the handle have been provided. We also demonstrate that EPC can coordinate the movement of the robot's omni-directional base and compliant arm while pulling open a door or drawer, which leads to significantly improved performance.

Through 40 trials with 10 different doors and drawers, we empirically demonstrated the robustness of the system. The robot succeeded in 37 out of 40 trials, and had no more than a single failure for any particular door or drawer.

Code

The Python code associated with this project can be downloaded from:
http://code.google.com/p/gt-ros-pkg/source/browse/#svn/trunk/hrl/code_publications/2010_icra_epc_pull

CAD Model of the Hook End Effector

The CAD model of the hook end effector used in this work can be downloaded from:
http://www.hsi.gatech.edu/hrl-wiki/index.php/Hook_End_Effector