Title: Dynamic simulation of serial robots under force control

Authors: Arun Dayal Udai; Subir Kumar Saha

Addresses: Department of Mechanical Engineering, Birla Institute of Technology, Mesra, Ranchi, India ' Department of Mechanical Engineering, Indian Institute of Technology Delhi, New Delhi, India

Abstract: The advantages of using force control in industrial robots are well known. Study of such systems in virtual environments in the form of simulation is of great help as most of the force controlled task works in close contact with the environment. In this paper, we show how to simulate different force control algorithms of a typical serial robot used in industries before deciding to choose a suitable one for real implementation. Hence, a proper dynamic model of the robot is essential which should be able to emulate the real robot, particularly if the robot moves at relatively higher speeds. This is done here using the concept of the decoupled natural orthogonal complement (DeNOC) matrices which is known to provide a recursive forward dynamic algorithm that is not only efficient but also numerically stable. Such simulation of robots under force control will allow users to tune the control gains without stopping the real robot on the production floor. Besides, such simulation can be used as an education tool as well to help beginners to explore various types of control algorithms and their performances. In addition, the framework for simulation proposed in this paper can work as a good test bench to test the performances of either a new control law or a different dynamic algorithm. As an illustration, the DeNOC based dynamics was substituted with MATLAB's SimMechanics which can also perform dynamic simulation. The comparison of the results validated the concept and correctness of the numerical simulations.

Keywords: simulation; force control; decoupled natural orthogonal complement; DeNOC.

DOI: 10.1504/IJIMR.2018.090946

International Journal of Intelligent Machines and Robotics, 2018 Vol.1 No.1, pp.79 - 108

Received: 09 Mar 2017
Accepted: 06 Apr 2017
Published online: 04 Apr 2018 *