Development of Wearable Micro-actuator Array for 3-D Virtual Tactile Displays


A novel 4 by 4 array of electromagnetic micro-actuators operating on the principle of voice-coil actuators is presented. The intended application of the array is dynamic tactile stimulation, where multiple actuators generate an illusion of touching a moving pattern. In comparison to earlier designs [1-3], the device has smaller dimensions of 2.28 mm in diameter and 7 mm in length, which allowed its use in an array capable of hosting up to a 5 by 5 set of actuators with a rectangular shape covering an area of 18 mm by 21 mm. Using finite element analysis of several conceptual designs of actuators [1,4,5], it was established that the voice-coil type device (where the coil is the moving part) has most beneficial characteristics for the envisioned application. These include sufficient force over a relatively large distance, allowing tactile stimulation of surfaces with irregular shape, fast response, and small foot-print that matches the density of the tactile sensory neurons in the human finger. Eexperimental evaluation of the operation of neighboring actuators spaced at 3.3 mm apart, indicates that there is no crosstalk between the actuators. The resulting density exceeds that of previously reported alternative designs based on moveable permanent magnets [4,6]. Static force measurement indicate that each micro-actuator can produce at least 26 mN of repulsive force over a stroke of 2100 μm with a peak force of 34 mN. The driving circuit operates at 13.5V and generates a vibration frequency of up to 265 Hz without significant change of the force-displacement characteristics. In the higher frequency range (above 100 Hz) the actuator provides at least 15 mN of force over a slightly reduced stroke of 2300 μm, and a peak force of 21 mN. All of the above parameters meet the required threshold values of tactile human perception known from [2] and [3].

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Z. Szabo and E. Enikov, "Development of Wearable Micro-actuator Array for 3-D Virtual Tactile Displays," Journal of Electromagnetic Analysis and Applications, Vol. 4 No. 6, 2012, pp. 219-229. doi: 10.4236/jemaa.2012.46031.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] F. M. Vidal-Verdu, “Graphical Tactile Displays for Visually-Impaired People,” IEEE Transactions on Neural Systems and Rehabilitation Engineering, Vol. 15, No. 1, 2007, pp. 119-130. doi:10.1109/TNSRE.2007.891375
[2] J. C. Stevens, “Aging and Spatial Acuity of Touch,” Journal of Gerontology: Psychological Sciences, Vol. 47, No. 1, 1992, pp. 35-40.
[3] K. B. Shimoga, “A Survey of perceptual Feedback Issues in Dexterous Telemanipulation: Part II. Finger Touch Feedback,” Virtual Reality Annual International Symposium, Seattle, 18-22 September 1993, pp. 271-279. doi:10.1109/VRAIS.1993.380769
[4] K. Deng and E. T. Enikov, “Design and Development of a Pulsed Electromagnetic Micro-Actuator for 3D Virtual Tactile Displays,” Mechatronics, Vol. 20, No. 4, 2010, pp. 503-509. doi:10.1016/j.mechatronics.2010.04.011
[5] M. Shimojo, et al., “Human Shape Recognition Performance for 3-D Tactile Display,” IEEE Transactions on Systems, Man, and Cybernetics—Part A: Systems and Humans, Vol. 29, No. 6, 1999, pp. 637-645. doi:10.1109/3468.798067
[6] M. Benali-Khoudja, M. Hafez and A. Kheddar, “VITAL: An Electromagnetic Integrated Tactile Display,” Displays, Vol. 28, No. 3, 2007, pp. 133-144. doi:10.1016/j.displa.2007.04.013
[7] K. Deng, E. T. Enikov and H. Zhang, “Development of a Pulsed Electromagnetic Micro-Actuator for 3D Tactile Displays,” IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Zurich, 4-7 September 2007, pp. 1-5. doi:10.1109/AIM.2007.4412457
[8] J. C. Bliss, et al., “Optical-to-Tactile Image Conversion for the Blind,” IEEE Transactions on Man-Machine Systems, Vol. 11, No. 1, 1970, pp. 58-65. doi:10.1109/TMMS.1970.299963
[9] C. C. Collins, “Tactile Television-Mechanical and Electrical Image Projection,” IEEE Transactions on ManMachine Systems, Vol. 11, No. 1, 1970, pp. 65-72. doi:10.1109/TMMS.1970.299964
[10] H. Iwata, et al., “Project FEELEX: Adding Haptic Surface to Graphics,” Proceedings of the 28th Annual Conference on Computer Graphics and Interactive Techniques, Los Angeles, 12-17 August 2001, pp. 469-476. doi:10.1145/383259.383314
[11] Y. Kawai and F. Tomita, “Interactive Tactile Display System—A Support System for the Visually Disabled to Recognize 3D Objects,” Proceedings of International ACM Conference on Assistive Technologies, Vancouver, 1996, pp. 45-50.
[12] T. Iwamoto, M. Tatezono, H. Shinoda, “Non-contact method for producing tactile sensation using airborne ultrasound,” Proceeding EuroHaptics ‘08 Proceedings of the 6th International Conference on Haptics: Perception, Devices and Scenarios, Madrid, 10-13 June 2008, pp. 504-513. doi:10.1007/978-3-540-69057-3_64
[13] M. I. Koo, et al., “Development of Soft-Actuator-Based Wearable Tactile Display,” IEEE Transactions on Robotics, Vol. 24, No. 3, 2008, pp. 549-559. doi:10.1109/TRO.2008.921561
[14] T. Fukuda, et al., “Micro Resonator Using Electromagnetic Actuator for Tactile Display,” Proceedings of the International Symposium on Micromechatronics and Human Science, Nagoya, 5-8 October 1997, pp. 143-155. doi:10.1109/MHS.1997.768872
[15] H. K. Kim, et al., “Fabrication and Test of a Micro Electromagnetic Actuator,” Sensors and Actuators A: Physical, Vol. 117, No. 1, 2005, pp. 8-16. doi:10.1016/j.sna.2003.10.079
[16] A. T. Kern, “Engineering Haptic Devices, A Beginner’s Guide for Engineers,” Springer-Verlag, Berlin, 2009.
[17] K. Deng, “Development of Virtual 3D Tactile Display Based on Electromagnetic Localization,” Ph.D. Thesis, Graduate College the University of Arizona, Tucson, 2009.
[18] M. Critchley, “Tactile Thought, with Special Reference to the Blind,” Proceedings of the Royal Society of Medicine, Vol. 46, No. 1, 1952, pp. 27-30.
[19] A. Pascual-Leone and F. Torres, “Plasticity of the Sensorimotor Cortex Representation of the Reading Finger in Braille Readers,” Brain, Vol. 116, No. 1, 1993, pp. 39-52. doi:10.1093/brain/116.1.39
[20] A. K. Kaczmarek, et al., “Electrotactile and Vibrotactile Displays for Sensory Substitution Systems,” IEEE Transactions on Biomedical Engineering, Vol. 38, No. 1, 1991.

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