Skip to main content

Surface Haptic Technology Development

About

“Surface haptics” is the creation of programmable haptic effects on physical surfaces such as touch screens. Our lab has pioneered an approach to surface haptics based on controlling the shear force at each fingertip. This enables fingertips to interact with physics-based virtual environments, much like force feedback devices enable the whole hand to do. Ultrasonic vibrations and electrostatic fields are used to produce the fingertip forces.

Active Force Feedback on Fingertips

LateralPaD

The LateralPaD is a surface haptic device that generates lateral (shear) force on a bare finger, by vibrating the touch surface simultaneously in both out-of-plane (normal) and in-plane (lateral) directions at the same ultrasonic frequency. The force that develops on the finger can be controlled by modulating the relative phase of the two  resonances. 

ActivePaD

ActivePadThe ActivePaD is a surface haptic interface that combines a variable friction device (the Large Area TPaD) with an impedance controlled planar mechanism. This device configuration allows control of the frictional force in the static friction regime, control of the direction of force in the kinetic friction regime, as well as a degree of control over the transition between the two regimes. 

ShiverPaD

The ShiverPaD is a haptic surface capable of controlling shear force on a bare finger. At the heart of the ShiverPaD is the TPaD variable friction device. It modulates the friction of a glass surface by using 39 kHz out-of-plane vibrations to reduce friction. To generate shear forces, the TPaD is oscillated in-plane (i.e., “shivered”) while alternating between low and high friction within each cycle.

Electrostatic Tactile Displays

With the ever-increasing presence of touch interfaces on mobile devices, purely electronic tactile displays show promise of practical application. This research pertains to the development of a new display using the principle of electrostatic attraction of fingertip skin to a charged surface. By taking advantage of electrical properties of human fingertips, a force can be generated on the finger with the application of an electric field. 

Electrostatic Tactile DisplayA thin transparent conductor (ITO) runs just beneath the outer surface of the glass, which is charged to attract the finger to screen. Electrostatic displays use the attraction forces to increase the friction force on a finger sliding across the surface. The focus of this work is to fully understand the electrostatic attraction of a finger to a charged surface and its effect on finger-surface interaction.  This work will ultimately lead to optimization in design of future tactile displays using electrostatic attraction.

Fingertip Mechanics 

A clear understanding of both the interaction between the surface and the fingertip and of the propagation of the acoustic energy to the skin and surrounding tissues is crucial for improving the surface-haptic devices and increase forces produced by acoustic emission.

Our lab is equipped with a custom made tribometrer that is able to control the velocity and the normal force of a fingertip exploring a surface. The output of this instrument helps us understand the underpinning of the fingertip friction and its modulation under electrostatic attraction and acoustic emission. On the other hand, we use elastography techniques to measure the transmission and the propagation of acoustic energy into the tissues. Both surface waves and body waves measurement informs on the nature of the tissues and their ability to capture the energy coming provided by the interface.

The output of this research will provide key design parameters for the to the improvement of future surface-haptic displays. Refined models will help us not only to increase the force output but also to be less sensitive to individual specificity and provide the same level of stimulation for everyone.

People

Edward Colgate
Michael Peshkin
Nick Marchuk
Joe Mullenbach
David Meyer
Michael Wiertlewski
Ben Richardson
Rebecca Fenton Friesen
Craig Shultz

Related Publications

Shultz, C., M. A. Peshkin, and E. J. Colgate, "Surface haptics via electroadhesion: Expanding electrovibration with Johnsen and Rahbek", 2015 IEEE World Haptics Conference (WHC)2015 IEEE World Haptics Conference (WHC), Evanston, IL, IEEE, pp. 57 - 62, 2015. Google Scholar 

Meyer, D. J., M. Wiertlewski, M. A. Peshkin, and J. E. Colgate, "Dynamics of ultrasonic and electrostatic friction modulation for rendering texture on haptic surfaces", Haptics Symposium (HAPTICS), 2014 IEEE: IEEE, 2014. Google Scholar 

Meyer, D. J., M. A. Peshkin, and J. E. Colgate, "Fingertip Friction Modulation due to Electrostatic Attraction", World Haptics Conference (WHC), 2013, 2013. Google Scholar

Mullenbach, J., C. Shultz, A. Marie Piper, M. A. Peshkin, and J. E. Colgate, "TPad Fire: Surface Haptic Tablet", HAID Haptic and Audio Interaction Design, Daejeon, Korea, Springer, 04/2013. Google Scholar 

Dai, X., J. E. Colgate, and M. A. Peshkin, "LateralPaD: A surface-haptic device that produces lateral forces on a bare finger", Haptics Symposium (HAPTICS), 2012 IEEE: IEEE, pp. 7–14, 2012. Google Scholar 

Mullenbach, J., D. Johnson, J. E. Colgate, and M. A. Peshkin, "ActivePaD surface haptic device", Haptics Symposium (HAPTICS), 2012 IEEE: IEEE, pp. 407–414, 2012. Google Scholar 

Chubb, E. C., J. E. Colgate, and M. A. Peshkin, "Shiverpad: A glass haptic surface that produces shear force on a bare finger", Haptics, IEEE Transactions on, vol. 3, no. 3: IEEE, pp. 189–198, 2010. Google Scholar 

Chubb, E. C., J. E. Colgate, and M. A. Peshkin, "ShiverPad: A device capable of controlling shear force on a bare finger", EuroHaptics conference, 2009 and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems. World Haptics 2009. Third Joint: IEEE, pp. 18–23, 2009. Google Scholar 

Back to top