In the University of Michigan Vibration and Acoustics Laboratory, micro-robotics research is currently focused on design, fabrication, and testing of millimeter- to centimeter-scale micro-robots. Research topics include:

  • High-force, large-stroke piezoelectric microactuators
  • Terrestrial microrobot gait analysis and testing
  • Solid-state battery modeling and power electronics optimization
  • Optimization of micro-robotic mechanism designs
  • Ultra-low-power, robust servo control
  • Low-power tactile sensing mechanisms
  • Sensor development for microrobot joint positioning

The key enabling technology for this effort is high-force, low-power piezoelectric micro-actuation, developed in collaboration with the U.S. Army Research Laboratory. Sample actuators are shown in the prototype robotic leg structures below. We seek to harness their unique capabilities through integration with high-aspect ratio micro-structures and ultra-low-power control strategies.



Sample Images: (Top) Prototype hexapod (2.5 mm x 5 mm) micro-robot prior to final release and after release for ground dynamics testing (Dr. Jongsoo Choi, Jinhong Qu); (Bottom left) Multi-degree-of-freedom robot leg joint (Dr. Choong-Ho Rhee); (Bottom Right) Circular actuator array, image courtesy U.S. Army Research Laboratory.


We also perform robot prototyping with a variety of meso-scale robotic systems, primarily to evaluate dynamic models for elastic piezoelectric robots.  Dynamic models is validated with respect to major features of robot motion, such as robot body motion velocity and robot leg bouncing patterns.  Resulting models provided good dynamic representations over various scales, from a few millimeters to several centimeters in size.

Examples of rapid-prototyped piezoelectric robots for ground-interaction dynamics testing (Jinhong Qu, Clark Teeple)



Dr. Ronald G. Polcawich, Jeffrey S. Pulskamp, and Ryan Q. Rudy, U.S. Army Research Laboratory, Adelphi MD

For additional information on Michigan Robotics activities, visit http://robotics.engin.umich.edu/


Army Research Office/Army Research Laboratory
National Science Foundation

Related Publications:

  1. J. Qu, C.B. Teeple, and K.R. Oldham, “Modeling legged micro-robot locomotion based on contact dynamics and vibration in multiple modes and axes,”ASME Journal of Vibration and Acoustics, vol. 193, no. 3, pp. 031013, 2017. (pdf)

  2. J. Choi, M. Shin, R.Q. Rudy, C.Kao, J.S. Pulskamp, R.G. Polcawich, and K.R. Oldham, “Thin-film piezoelectric and high-aspect ratio polymer leg mechanisms for millimeter-scale robotics,”  International Journal of Intelligent Robotics and Applications, vol. 1, no. 2, pp. 180-194, 2017. (pdf)

  3. K. Teichert and K.R. Oldham, “Modeling cyclic capacitive loading of thin-film batteries,” Journal of the Electrochemical Society, vol. 164, no. 2, pp. A360-A369, 2017. (pdf)

  4. M. Shin, J. Choi, R.Q. Rudy, C.  Kao, J.S. Pulskamp, R.G. Polcawich, K.R. Oldham, “Micro-robotic actuation units based on thin-film piezoelectric and high-aspect ratio polymer structures,” Proceedings of the ASME International Design Engineering Technical Conferences, Buffalo, NY, August 2014.

  5. J. H. Ryou and K. R. Oldham, “Dynamic characterization of contact interaction of micro-robotic leg structures,” Journal of Smart Materials and Structures, vol. 23, no. 5, 055014, 2014. (pdf)

  6. B. Edamana and K.R. Oldham, “A near-optimal sensor scheduling strategy for an on-off controller with an expensive sensor,” IEEE/ASME Transactions on Mechatronics, vol. 19, no. 1, pp. 158-170, 2014. (pdf)

  7. B. Hahn and K. Oldham, “Convergence and energy analysis for iterative adaptive On-Off control of piezoelectric microactuators,” IEEE Transactions on Control Systems Technology, vol. 23, no. 3, pp. 1052-1060, 2013. (pdf)

  8. B. Edamana and K. Oldham, “Optimal low-power piezoelectric actuator control with charge recovery for a micro-robotic leg,” IEEE/ASME Transactions on Mechatronics, 18(1), 251-262, 2013. (pdf)

  9. C.S. Casarez, J.H. Ryou, and K.R. Oldham, “Dimensional analysis of dynamic MEMS micro-robotic walking subject to orthogonal actuation and small-scale forces,” Proceedings of the 2013 ASME International Design Exposition and Technical Congress, Portland, OR, August 2013.

  10. C.H. Rhee, J.S. Pulskamp, R.G. Polcawich, and K.R. Oldham, “Multi-degree-of-freedom thin-Film PZT actuated micro-robotic leg,” IEEE Journal of Microelectromechanical Systems, 21(6), 1492-1503, 2012. (pdf)

  11. R. Rudy, A. J. Cohen, J. S. Pulskamp, R. G. Polcawich, and K.R. Oldham, “Antenna-like tactile sensor for thin-film piezoelectric micro-robots,”  Proceedings of the 2013 ASME International Design Exposition and Technical Congress, Portland, OR, August 2013.

  12. B. Edamana, B. Hahn, and K. Oldham, “Modeling and Optimal Low-Power On-Off Control of Thin-Film Piezoelectric Actuators,” IEEE/ASME Transactions on Mechatronics,” 16(5), 884-896 (2011).  (pdf)
  13. B. Hahn and K. Oldham, “A Model-Free On-Off Iterative Adaptive Controller Based on Stochastic Approximation,” IEEE Transactions on Control Systems Technology, 20(1), 196-204 (2012). (pdf)
  14. B. Hahn and K. Oldham, “On-Off Iterative Adaptive Controller for Low-Power Micro-Robotic Step Regulation,” Asian Journal of Control, 14(3) 624-640 (2012) (pdf)
  15. J.H. Ryou and K. Oldham, “Foot-terrain Interaction for a Prototype Silicon Micro-Robot,” Proceedings of ASME Dynamic Systems and Control Conference, Arlington, VA (2011) (pdf)
  16. C.H. Rhee and K. Oldham, “Robust Finite Duration Transient Reponse of a Micro-Electromechanical System,” Proceedings of the American Controls Conference, San Francisco, CA (2011) (pdf)
  17. K. Oldham, J. Pulskamp, R. Polcawich, and M. Dubey, “Thin-film Piezoelectric Lateral Actuators with Extended Stroke,” IEEE Journal of Microelectromechanical Systems, 17(4), 890-899 (2008) (pdf)
  18. K. Oldham, J. Pulskamp, R. Polcawich, P. Ranade, and M. Dubey, “Thin-Film Piezoelectric Actuators for Bio-Inspired Micro-Robotic Applications,” Integrated Ferroelectrics, 95(1), 54-65, (2008) (pdf)