Force and trajectory control of industrial robots in stiff contact

Position-based force control is presented, incorporating compliance in the robot joints and possibly in a force- / torque-sensor and/or the environment. First, the total compliance is identified. Then, in the control phase, the desired pose of the tool center point is computed from the force control error. Thus standard position control may be applied. This leads to an inherently stable control scheme, even with a low sampling rate of the sensor interface and unknown environmental compliance. The method is designed for applications of industrial robots, e.g. assembly tasks. Parallel control considers the existence of a reference trajectory which allows feedforward in force controlled directions. The paper further examines couplings between forces and torques, which are important for partially constrained configurations. A possible impact force is considered when colliding with an unexpected object.

[1]  Lorenzo Sciavicco,et al.  The parallel approach to force/position control of robotic manipulators , 1993, IEEE Trans. Robotics Autom..

[2]  Louis L. Whitcomb,et al.  Adaptive force control of position/velocity controlled robots: theory and experiment , 2001, Proceedings 2001 IEEE/RSJ International Conference on Intelligent Robots and Systems. Expanding the Societal Role of Robotics in the the Next Millennium (Cat. No.01CH37180).

[3]  H. Van Brussel,et al.  Compliant robot motion, I, II , 1988 .

[4]  Luigi Villani,et al.  Force Control , 2021, Springer Handbook of Robotics, 2nd Ed..

[5]  Friedrich Lange,et al.  Assembling wheels to continuously conveyed car bodies using a standard industrial robot , 2010, 2010 IEEE International Conference on Robotics and Automation.

[6]  Gunther Reinhart,et al.  Flexible Automation for the Assembly in Motion , 2007 .

[7]  Chao Liu,et al.  Soft tissue force control using active observers and viscoelastic interaction model , 2012, 2012 IEEE International Conference on Robotics and Automation.

[8]  David Navarro-Alarcon,et al.  Energy shaping control for robot manipulators in explicit force regulation tasks with elastic environments , 2011, 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[9]  Hendrik Van Brussel,et al.  Compliant Robot Motion II. A Control Approach Based on External Control Loops , 1988, Int. J. Robotics Res..

[10]  Paolo Rocco,et al.  Implicit force control for industrial robots in contact with stiff surfaces , 1996, Autom..

[11]  Paolo Rocco,et al.  Toward the implementation of hybrid position/force control in industrial robots , 1997, IEEE Trans. Robotics Autom..

[12]  William Eakins,et al.  Robotic wheel loading process in automotive manufacturing automation , 2009, 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[13]  Alin Albu-Schäffer,et al.  A versatile biomimetic controller for contact tooling and haptic exploration , 2012, 2012 IEEE International Conference on Robotics and Automation.

[14]  Mats Björkman,et al.  Cost-efficient drilling using industrial robots with high-bandwidth force feedback , 2010, Robotics and Computer-Integrated Manufacturing.

[15]  Marcelo H. Ang,et al.  Active compliance control of a PUMA 560 robot , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[16]  Friedrich Lange,et al.  Revised force control using a compliant sensor with a position controlled robot , 2012, 2012 IEEE International Conference on Robotics and Automation.

[17]  Martin Buss,et al.  Force Tracking Impedance Control with Variable Target Stiffness , 2008 .

[18]  J. Grewe,et al.  Compliant-Force-Torque-Sensor , 2001 .

[19]  J. De Schutter,et al.  Compliant Robot Motion II. A Control Approach Based on External Control Loops , 1988 .

[20]  Alexander Verl,et al.  Superimposed Force/Torque-Control of Cooperating Robots , 2010, ISR/ROBOTIK.

[21]  Neville Hogan,et al.  Stable execution of contact tasks using impedance control , 1987, Proceedings. 1987 IEEE International Conference on Robotics and Automation.

[22]  John J. Craig,et al.  Hybrid position/force control of manipulators , 1981 .

[23]  Bruno Siciliano,et al.  Integration for the next generation: embedding force control into industrial robots , 2005, IEEE Robotics & Automation Magazine.