A proposal of grasping information interface for remote pointing task

Grasping-and-moving are fundamental hand operations necessary for performing tasks using modern man-machine interfaces. However, behavioral information associated with grasping, such as force, posture, etc., has not been utilized for traditional interfaces. Although behavioral information should have potential utility in developing task-adaptive and operator-adaptive interfaces; it is known that how people grasp devices is dependent on the purpose of these tasks. This paper describes a computer mouse as a typical pointing device, whose approaching speed, or gain, is adjusted depending on the nature of the task. This paper suggests that the grasping-and-moving tasks should consist of two phases. The first or approaching phase is when the operator moves the mouse pointer close to the target with a small grasping force. The second or positioning phase follows when the operator makes a fine adjustment of the pointer to locate it within the target area using a larger grasping force. This proposed new computer mouse has a sensor to detect the operator´s grasping force and uses it to control the gain of the mouse. Two sets of experiments were conducted; one for confirming the assumption that the grasping force should be small while approaching the target and large while positioning it; and the other for confirming that the proposed mouse should be effective in reducing the time necessary for pointing various kinds of objects.