g_compensation

• This repository contains the g_compensator ROS node.

• The node subscribes to a Wrenched Stamped topic performes a non-dynamical gravitation compensation and publishes another Wrenched Stamped topic

• The correction is based on the parameter mass in kg, com_frame (center of mass) as tf-frame id, gravity_frame (world frame) as tf-frame id with gravity pointing in negative z-direction with g=9.81. All parameters are to be set on the parameter-server

• All calculations are based on PyKDL and tf2

• Some manipulators, like the KUKA iiwa or the Franka Emika Panda, publish the wrench data of their force-torque sensor in the opposite convention. I.e., they publish the wrench with which the environment acts on the manipulator. To convert such a signal into the more usual definition (the wrench with which the manipulator acts on the environment), the parameter negate_wrench can be set to True (default: False).

• A rosservice /tare can be called to tare in the current pose.

Acknowledgements

This project is a result of the LIAA project. http://www.project-leanautomation.eu/

LIAA received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 608604.

Project runtime: 02.09.2013 – 31.08.2017.