Development of a Human-Display Interface with Vibrotactile Feedback for Real-World Assistive Applications.

It is important to operate devices with control panels and touch screens assisted by haptic feedback in mobile environments such as driving automobiles and electric power wheelchairs. A lot of consideration is needed to give accurate haptic feedback, especially, presenting clear touch feedback to the elderly and people with reduced sensation is a very critical issue from healthcare and safety perspectives. In this study, we aimed to identify the perceptual characteristics for the frequency and direction of haptic vibration on the touch screen with vehicle-driving vibration and to propose an efficient haptic system based on these characteristics.

Investigation on Low Voltage Operation of Electrovibration Display.

This paper presents three methods of input voltage signals that allow low voltage operation of an electrovibration display while preserving the perceptual feel and strength of electrovibration stimuli. The first method uses the amplitude modulation of a high-frequency carrier-signal. The second method uses a dc-offset, and the third method uses a combination of the two methods.

Method for Providing Electrovibration with Uniform Intensity.

Electrovibration is a type of surface haptics that can modulate lateral forces acting between a fingertip and a touch surface. Electrovibration is fast, consumes little power, and does not involve the use of any mechanical actuators. However, it suffers from problems such as nonuniform perceived intensity due to varying environmental impedances, as well as possible electric shock, which have to be solved for commercialization.

Smooth Vibrotactile Flow Generation Using Two Piezoelectric Actuators.

This paper proposes a method for generating a smooth directional vibrotactile flow on a thin plate. While actuating two piezoelectric actuators spatially across the plate, temporal sweeping of the input excitation frequency from zero to the first mode of the resonance frequency can smooth the perceived directional vibrotactile flow, as compared to a vibrotactile flow generated by conventional apparent tactile movement and phantom sensation methods. In order to ascertain important factors in the excitation pattern, a user study was conducted for three factors (amplitude (constant versus modulated), frequency (constant versus swept), and ending shape (sharp versus smooth)).