Multijoint grasping movements. Simulated and observed effects of object location, object size, and initial aperture.

摘要: Studies of human prehension have revealed characteristic patterns grasping kinematics. We sought to gain insight into the determinants those by means a computer simulation and accompanying behavioral experiment concerning multijoint, planar behavior. The was based on recent theory posture-based motion planning which hypothesizes that movement preparation entails time-limited, multiple task-constraint satisfaction. Prehension modeled with stick-figure animation involving 12 series 81 movements. Circular objects be grasped were located at three angles (45°, 90°, 135°) distances (20 cm, 30 40 cm) relative initial location hand in workplane. Additionally, object sizes (2 4 6 cm diameter) aperture (0.3 3.3 7.0 used. Analyses simulated movements focused time course opening, tangential velocity wrist, rotations joints arm, hand, fingers. results showed model accurately mimicked detailed kinematics observed earlier studies. With respect frequently reported relationship between size simulations further an effect aperture. This predicted confirmed four participants performed analogous tasks. An analysis opening maximum covaried A conclusion this work is major determinant avoidance collisions are grasped.