UGV System Reliability Modeling & Improvement

Principal Investigators: Judy Jin, University of Michigan, jhjin(at)umich.edu
A. Galip Ulsoy, University of Michigan, ulsoy(at)umich.edu
Student: Amir Sadrpour, Rob Brown, University of Michigan
Government: Matthew Castanier (Point of contact), Greg Hudas, U.S. Army TARDEC
Industry: Rainer Gasche, Jason Suchman, iRobot

Energy Reliable Dynamic Path PlanningWork began in 2010 and was completed in 2013.

Despite significant developments in robotics and autonomous vehicles, insufficient attention has been paid to ensuring reliability under difficult and uncertain operating conditions in the field.

The project goal is to develop methods to improve the reliability of unmanned ground vehicles (UGVs). This research produced methods for performance validation, and operational failure modeling and analysis based on UGV simulation-based acceptance testing, and system reliability modeling and assessment, including the varying roles of the UGV mission. We also developed methods for UGV end-of-mission energy prediction based on real-time data and prior knowledge. This was extended to methods for real-time prediction of mission energy and adaptive task planning for preventing UGVs from unanticipated power depletion failures in 2013, and incorporated into the 2013 robotics case study.

A second specific focus was to improve the reliability, utility and efficiency of the electromechanical design of a robot arm attached to a UGV. DC motors wears out relatively quickly if operated at or near their stall torque. Therefore, if a simple redesign of the mechanical system, such as adding a torsional spring, can result in an arm where the motors need not use so much torque, then the UGV is made more reliable. Alternatively, if a smaller torque is needed to lift a given load, then the total load that can be lifted increases, thus the utility of the UGV is increased. This redesign can potentially reduce the amount of energy required to perform a given maneuver, thus increasing the efficiency. The work on robust design of passive assist systems for robot arms was completed during 2010-2012.

Publications:

  • D. M. Tilbury, A. G. Ulsoy, "A New Breed of Robots That Drive Themselves", ASME Mechanical Engineering Magazine, Vol. 133, No. 2, pp 28-33, February 2011.
  • W. R. Brown, A. G. Ulsoy, "A Maneuver Based Design of a Passive-Assist Device for Augmenting Active Joints", Journal of Mechanisms and Robotics 5(3), 031003, 2013.
  • A. Sadrpour, A. G. Ulsoy, J. Jin, "Mission Energy Prediction for Unmanned Ground Vehicles Using Real-time Measurements and Prior Knowledge", Journal of Field Robotics, Volume 30, Issue 3, pages 399–414, May/June 2013.
  • A. Sadrpour, J. Jin, A. G. Ulsoy, "Mission Energy Prediction for Unmanned Ground Vehicles Using Real-time Measurements and Prior Knowledge", Journal of Field Robotics, vol. 30, is. 3, pp. 399-414, 2013.
  • A. Sadrpour, H. J. Lee, J. Jin, A. G. Ulsoy, "Simulation-Based Acceptance Testing For Unmanned Ground Vehicles", International Journal of Vehicle Autonomous Systems, Vol. 11, No. 1, pp. 62-85, 2013.
  • W. R. Brown, A. G. Ulsoy, "A Passive-Assist Design Approach for Improved Reliability and Efficiency of Robot Arms", Proceedings of the IEEE International Conference on Robotics and Automation (ICRA 2011), Shanghai, China, May 2011.
  • W. R. Brown, A. G. Ulsoy, "Experimental Verification of a Passive-Assist Design Approach for Improved Reliability and Efficiency of a Robot Arms", Proceedings of the ASME 5th Dynamic Systems and Control Conference, Paper No. DSCC2012-MOVIC2012-8798, pp. 113-122, 2012.
  • W. R. Brown, A. G. Ulsoy, "Experimental Verification of a Passive-Assist Design Approach for Improved Reliability and Efficiency of a Robot Arms", Proceeding of the ASME DSCC, Fort Lauderdale, October 2012.
  • A. Sadrpour, J. Jin, A. G. Ulsoy, "Mission Energy Prediction for Unmanned Ground Vehicles", Proceedings of the IEEE International Conference on Robotics and Automation (ICRA), Minneapolis, MN, 14-18 May 2012.
  • A. Sadrpour, J. Jin, A. G. Ulsoy, "Experimental Validation of Mission Energy Prediction Model for Unmanned Ground Vehicles ",Proceedings of the American Control Conference (ACC), pp. 5960-5965, Washington, DC, June 2013.
  • W. R. Brown, A. G. Ulsoy, "Maneuver Based Design of a Passive-Assist Device for Augmenting Linear Motion Drives", Proceedings of the American Control Conference (ACC), pp. 4530 - 4537, Washington, DC, June 2013.
  • A. Sadrpour, J. Jin, A. G. Ulsoy, "Real-Time Energy-Efficient Path Planning for Unmanned Ground Vehicles Using Mission Prior Knowledge", Proceedings of the ASME Dynamic Systems and Control Conference, pp. V003T47A002-V003T47A002, 2013.