Steve Shen

Mechanical Engineering

  • (206) 543-5718
  • MEB 313


  • Ph.D., University of California, Berkeley, 1991
  • M.S., National Taiwan University, Taipei, 1986
  • B.S., National Taiwan University, Taipei, 1981

Research Statement

Professor Shen's general research areas include vibration, dynamics, sensing, and actuation. Currently, his research focuses on the following subjects: (a) lead-zirconate-titanate (PZT) thin-film technologies, (b) medical devices, (c) insect wing/flight dynamics, and (d) vibration of rotary machines.

In the area of PZT thin-film technologies, his research team develops and manufactures two types of PZT thin films for sensors and actuators. One is a homogenous PZT thin film on silicon (rigid) substrate, and the other is a PZT-silane nano-composite thin film on polymer (flexible) substrate. The homogeneous PZT thin films are sol-gel derived, and the thin-film sensors or actuators are fabricated in clean rooms. The PZT-silane composite thin films are fabricated via various methods, such as 3-D printing, ink-jet printing, spin coating, and drop casting. Applications include medical devices and structural health monitoring sensors, for example.

In the area of medical devices, his research team designs and develops (a) introcochlear acoustic microacutators for hybrid cochlear implants, (b) introcochlear microphones for totally implantable cochlear prostheses, (c) diagnostic tools to evaluate stability of dental implants, and (d) futuristic ultrasound devices. Professor Shen not only studies the dynamics of these medical devices, but also instruments these devices with calibrated experiments. For example, his research team analyzed and measured vibration of intracochlear microactuators in aqueous environments. Moreover, acute animal tests were performed to prove the concept of the intracochlear microactuators.

In the area of insect wing/flight dynamics, his research objectives are (a) to dynamically model the complicated mechanisms crucial for highly versatile insect flight, (b) to use the models to advance design of micro-aerial vehicles (MAV), and (c) to develop key sensors and actuators for better guidance and control of MAV. For example, his research team has developed and validated an inertial-elastic model of the insect forewing in air and in vacuum (and also won a best paper award). Moreover, his research team has concluded that modest changes in stroke deviation can significantly affect steering. Both aerodynamic and inertial torques are critical to maneuverability, while the former dominates in steady-state flights and the latter is significant during short transients.

In the area of rotary machines, his research team has developed computational algorithms to predict vibration and understand the physics of complex rotating machines, such as (a) hard disk drives (HDD), (b) cyclic symmetric rotors (e.g., turbines), and (c) mistuned rotors. For HDD, his research focuses on spindle vibration, fluid-dynamics bearing technologies, actuators, suspensions, and heads. For cyclic symmetric rotors, he studies interaction between the spinning rotor and a stationary housing via multiple bearing supports. For mistuned rotors, he studies formation of mode localization phenomena and how presence of bearings and housing affects mode localization.

More about Professor Shen's research

Select publications

  1. M. Jankauski and I. Y. Shen, 2016: Experimental Studies of an Inertial-Elastic Rotating Wing in Air and Vacuum, International Journal of Micro Air Vehicles, vol. 8, pp. 53-63.
  2. Weiwei Xu, Hsien-Lin Huang, Yifeng Liu, Chuan Luo, G. Z. Cao, I.Y Shen, 2016, “Fabrication and Characterization of PZT-Silane Nano-Composite Thin-Film Sensors,” Sensors and Actuators A—Physical, vol. 246, pp. 102-113.
  3. Chuan Luo, Irina Omelchenko, Robert Manson, Carol Robbins, Elizabeth C. Oesterle, G. Z. Cao, I. Y. Shen, Clifford R. Hume, 2015 “Direct Intracochlear Acoustic Stimulation using a PZT Microactuator,” Trends in Hearing, Vol. 19, pp.1-14.
  4. W. C. Tai, and I. Y. Shen, 2015: Ground-Based Response of a Spinning, Cyclic Symmetric Rotor Assembled to a Flexible Stationary Housing via Multiple Bearings. ASME Journal of Vibration and Acoustics, Vol. 137, pp. 041011-1 to 041011-12.
  5. Y. F. Chen and I. Y. Shen, 2015: Mathematical Insights of Mode Localization in Nearly Cyclic Symmetric Rotors with Mistune, ASME Journal of Vibration and Acoustics, Vol. 137, pp. 041007-1 to 041007-13.
  6. Hsien-Lin Huang, G. Z. Cao, and I. Y. Shen, 2014: Hydrothermal Synthesis of Lead Zirconate Titanate (PZT) Nano-Particles Using Controlled Ramping and Cooling Rates. Sensors and Actuators A—Physical, Vol. 214, pp. 111-119.
  7. Chuan Luo, G. Z. Cao, and I. Y. Shen, 2013: Development of a Lead-Zirconate-Titanate (PZT) Thin-Film Microactuator Probe for Intracochlear Applications. Sensors and Actuators A—Physical, Vol. 201, pp. 1-9.
  8. I. Y. Shen, Liu Mengjun, Gao Feng, Lee Chong Wee, Lin Wuzhong, and Ong Eng Hong, 2013: Extraction of Bearing Coefficients of Fluid-Dynamic Bearing Spindle Motors Using a Proof Mass and a Hammer—A Refined Approach. IEEE Transaction of Magnetics, Vol. 40, pp. 2755-2761.
  9. Q. Guo, G. Z. Cao, and I. Y. Shen, 2013: Measurements of Piezoelectric Coefficient d33 of Lead Zirconate Titanate (PZT) Thin Films Using a Mini Force Hammer. ASME Journal of Vibration and Acoustics, Vol. 135, paper 011003.
  10. Tsung-Liang Wu and I. Y. Shen, 2009: Position Error Predictions of a Hard Disk Drive Undergoing a Large Seeking Motion with Shock Excitations, IEEE Transaction of Magnetics, Vol. 45, pp. 5156-5161.
  11. Hyunchul Kim, Nicholas T. K. Colonnese, and I. Y. Shen, 2009: Mode Evolution of Cyclic Symmetric Rotors Assembled to Flexible Bearings and Housing. ASME Journal of Vibration and Acoustics, pp. 051008, 1-9.

Honors & awards

  • N. O. Myklestad Award, American Society of Mechanical Engineers, 2017
  • Best Paper Award, International Micro Air Vehicle Conference and Competition, Delft, The Netherlands, August 12-15, 2014
  • Valued Reviewer, Sensors and Actuators A – Physical, 2009
  • Distinguished Guest, Data Storage Institute, Singapore, 2007
  • ME Outstanding Faculty of the Year Award, 1998, 2003, 2004
  • IBM Partnership Award, 1998