Quantitative Investigation of Hand Grasp Functionality: Hand Joint Motion Correlation, Independence, and Grasping Behavior

Table 1

Summary of selected precious studies on grasp classification for describing hand grasp functionality.

Study	Total number of hand grasps	Classification definition	Description
Schlesinger [11]	6	Object shape	Six typical postures are proposed to describe hand grasp functionality according to the object shape.
Napier [12], Kamakura et al. [13]	14	Action goals (power, precision, intermediate grasp)	Power grasp holds object stably, while precision grasp imparts the object motion [12].; Intermediate grasp represents the postures with contact areas of finger-side aspect [13].
Iberall and Iberall and Bingham [14]-[16]	25	Oppositional force and virtual finger	For a given manual task, the grasp can be classified by the oppositional force exerted between virtual finger surfaces. Palm, pad, and side opposition means oppositional force along a direction perpendicular, parallel, and transverse to the palm, respectively.
Cutkosky [17]	16	Synthesis	Cutkosky [17] proposed a hierarchical tree of grasps, totally listing 16 different grasps.; The grasp type, action goal, and VF oppositional force are synthetically considered.
Stival et al. [18], Jarque-Bou [19]	20	Synthesis	Stival et al. and Jarque-Bou et al. [18, 19] built a taxonomy that contained 20 grasp types.; The grasp type, action goal, and VF oppositional force are synthetically considered.
Feix et al. [20]	33	Synthesis	Feix et al. [20] constructed a grasp taxonomy that contained 33 human grasp types.; The grasp type, action goal, and VF oppositional force are synthetically considered.