Taro Maeda

Lead-me interface for a pulling sensation from hand-held devices

When a small mass in a hand-held device oscillates along a single axis with asymmetric acceleration (strongly peaked in one direction and diffuse in the other), the holder typically experiences a kinesthetic illusion characterized by the sensation of being continuously pushed or pulled by the device. This effect was investigated because of its potential application to a hand-held, nongrounded, haptic device that can convey a sense of a continuous translational force in one direction, which is a key missing piece in haptic research. A 1 degree-of-freedom (DOF) haptic device based on a crank-slider mechanism was constructed. The device converts the constant rotation of an electric motor into the constrained movement of a small mass with asymmetric acceleration. The frequency that maximizes the perceived movement offered by the haptic device was investigated. Tests using three subjects showed that for the prototype, the best frequencies were 5 and 10 cycles per second.

Phantom-DRAWN: direction guidance using rapid and asymmetric acceleration weighted by nonlinearity of perception

This paper describes the design of a novel force perception method and the development of a handheld force display based on the method. The method is based on the nonlinear characteristics of human tactile perception; humans feel rapid acceleration more strongly than slow acceleration. The method uses periodic prismatic motion to create asymmetric acceleration leading to a virtual force vector. A prototype of the handheld force display that generates one-directional force using a relatively simple mechanism was built, and its performance tested in terms of both physical and perceptual characteristics. We verify the feasibility of the proposed method through experiments that determine the displays motors rotational frequency that maximizes the perception of the virtual force vector.

Kinesthetic Illusion of Being Pulled Sensation Enables Haptic Navigation for Broad Social Applications

Many handheld force-feedback devices have been proposed to provide a rich experience with mobile devices. However, previously reported devices have been unable to generate both constant and translational force. They can only generate transient rotational force since they use a change in angular momentum. Here, we exploit the nonlinearity of human perception to generate both constant and translational force. Specifically, a strong acceleration is generated for a very brief period in the desired direction, while a weaker acceleration is generated over a longer period in the opposite direction. The internal human haptic sensors do not detect the weaker acceleration, so the original position of the mass is washed out. The result is that the user is tricked into perceiving a unidirectional force. This force can be made continuous by repeating the motions. This chapter describes the pseudoattraction force technique, which is a new force feedback technique that enables mobile devices to create a the sensation of two-dimensional force. A prototype was fabricated in which four slider-crank mechanism pairs were arranged in a cross shape and embedded in a force feedback display. Each slider-crank mechanism generates a force vector. By using the sum of the generated vectors, which are linearly independent, the force feedback display can create a force sensation in any arbitrary direction on a two-dimensional plane. We also introduce an interactive application with the force feedback display, an interactive robot, and a vision-based positioning system.