Analysis of Novel Magnetic-Spring Actuators for Portable Units

휴대장치용 새로운 자기 스프링 액추에이터의 해석

  • 한인환 (홍익대학교 기계정보공학과)
  • Published : 2004.12.01


SLA(Scanned Linear Array) is a portable display unit for implementing next-generation virtual realities, utilizes a design that light generated by a line of LEDs is reflected from the rapidly oscillating mirror to generate a raster display. Reaction forces generated by the motions of the mirror and counter-balance mass cancel each other at the device base, reducing vibration. Metal leaf springs have been extensively applied in such portable units. Magnetic springs have been developed and adopted that can replace the metal spring and can avoid many disadvantages of metal springs. We model and analyze the dynamics of the structure with magnetic springs and present the simulation and experimental analysis results, which can be utilized for identifying and eliminating possible problem sources in removing shaking forces and moments, and oscillating the mirror at the required amplitude and frequency. Finally, we present the improved novel magnetic actuator model which can be applied in portable display units.


Portable Display Unit;Shaking Forces;Balance;Magnetic Springs


  1. Han, I., 1998, Dynamic Analysis and Optimum Design of the Actuator for SLA Apparatus, KETI-RD-98050, MIC
  2. Zang, S.M. and Chen, J.H., 1995, 'The Optimum Balance of Shaking Force and Shaking Moment of Linkage,' Mech. Mach. Theory, Vol. 30, No.4, pp. 589-597
  3. Lee, T.W. and Cheng, C., 1984, 'Optimum Balancing of Combined Shaking Force, Shaking Moment, and Torque Fluctuations in High-Speed Linkages,' ASME Journal of Mechanisms, Transmissions, and Automation in Design, Vol. 106, pp. 242-251
  4. Tricamo, S.J. and Lowen, G.G., 1981, 'A New Concept for Force Balancing Machines for Planar Linkages. Part 1: Theory,' ASME Journal of Mechanical Design, Vol. 103, pp. 637-642
  5. Bagci, C., 1983, 'Complete Balancing of Space Mechanisms-Shaking Force Balancing,' ASME Journal of Mechanisms, Transmissions, and Automation in Design, Vol. 105, pp. 609-616
  6. Yu, Y.-Q. and Lin, J., 2003, 'Active Balancing of a Flexible Linkage with Redundant Drives,' ASME Journal of Mechanical Design, Vol. 125, pp. 119-123
  7. Idlani, S., Streit, D.A. and Gilmore, B.J., 1993, 'Elastic Potential Synthesis-A Generalized Procedure for Dynamic Synthesis of Machine and Mechanism Systems,' ASME Journal of Mechanical Design, Vol. 115, pp. 568-575
  8. Shin, E. and Streit, D.A., 1997, 'Harmonic Synthesis Theory for Dynamic Spring Balancing,' ASME Journal of Dynamic Systems, Measurement, and Control, Vol. 119, No.1, pp. 61-68
  9. Wells, B.A., 1990, 'Low Vibration Resonant Scanning Unit for Miniature Optical Display Apparatus,' United States Patent 4902083
  10. Qian, K.-X., Zeng, P., Ru, W.-M. and Yuan, H.-Y., 2003, 'Novel Magnetic Spring and Magnetic Bearing,' IEEE Trans. on Magnetics, Vol. 39, No.1, pp. 559-561