KINEMATIC ANALYSIS OF MOUSE CURSOR POSITIONING AS A FUNCTION OF MOVEMENT SCALE AND JOINT SET

This study examined the impact of movement scale and joint set on the trajectories of rapid pointing movement made with a mouse. Participants manipulated a mouse to point a cursor to targets on a display of varying size and distance. The mouse movement was scaled independently of the display size by varying the control gain. Large-scale movements involving proximal joints (forearm) yielded longer movement times than small-scale movements involving distal joints (wrist, fingers). However, participants had particular difficulty placing the cursor on precise targets located in near space. This was evidenced in the kinematic analysis which revealed a relatively shorter distance traveled in the primary submovement and a greater proportion of movement time spent making secondary adjustments. These results suggest that the primary limiting factor in mouse pointing is its affordance of a power grip which limits the mobilization of the fingers for fine-grained movement.