Abstract: A hydraulic pump assembly (72) comprises: a low-pressure hydraulic pump (74), a high-pressure hydraulic pump (76), and a drive shaft assembly (78) that passes along an axis of the pump assembly (72); wherein both hydraulic pumps (74, 76) are arranged to be rotated simultaneously by the drive shaft assembly (78); and wherein the pump assembly (72) is formed a single unit arranged to fit into a pump chamber (80).

Abstract: A digit mechanism for an artificial hand comprises: a lower digit (44) arranged to be rotatably coupled to a palm unit (12) of the artificial hand; an upper digit (48) rotatably coupled to the lower digit (44); a lower digit rotation mechanism (34, 46, 52, 58) for applying a moment to the lower digit (44) to rotate the lower digit (44) relative to the palm unit (12); an upper digit rotation mechanism (50, 54, 56) for applying a moment to the upper digit (48) to rotate the upper digit (48) relative to the lower digit (44); and a force balancing mechanism (60, 58) for mechanically adjusting the magnitude of the moment applied by the lower digit rotation mechanism (34, 46, 52, 58) and/or the upper digit rotation mechanism (50, 54, 56) in accordance with the magnitude(s) of outside forces resisting rotation of the upper digit (48) and/or the lower digit (44) in order to preferentially apply movement to the digit experiencing lower resistance to movement; wherein the force balancing mechanism is arranged to increa

Abstract: A palm unit for an artificial hand comprises: a palm unit body (70); a motor (68) held by the palm unit body (70); a hydraulic pump assembly (72) held by the palm unit body (70) and comprising a low-pressure hydraulic pump (76) and a high-pressure hydraulic pump (74), wherein both hydraulic pumps (74, 76) are powered simultaneously by the motor (68); and a hydraulic circuit held by the palm unit body (70) and coupled to both hydraulic pumps (74, 76), wherein the hydraulic circuit has a low-pressure configuration in which the discharge sides of both hydraulic pumps (74, 76) are coupled to one or more hydraulic actuator(s) (36, 38) for the artificial hand and a high-pressure configuration in which the discharge side of the low-pressure pump (76) is isolated from the hydraulic actuator(s) (36, 38) and recirculates fluid to the suction side of the low pressure pump (76) with the discharge side of the high-pressure pump (74) remaining coupled to the hydraulic actuator(s) (36, 38), and wherein the hydraulic circuit

Abstract: A digit mechanism for an artificial hand comprises: a lower digit (44) arranged to be rotatably coupled to a palm unit (12) of the artificial hand; an upper digit (48) rotatably coupled to the lower digit (44); a lower digit rotation mechanism (34, 46, 52, 58) for applying a moment to the lower digit (44) to rotate the lower digit (44) relative to the palm unit (12); an upper digit rotation mechanism (50, 54, 56) for applying a moment to the upper digit (48) to rotate the upper digit (48) relative to the lower digit (44); and a force balancing mechanism (60, 58) for mechanically adjusting the magnitude of the moment applied by the lower digit rotation mechanism (34, 46, 52, 58) and/or the upper digit rotation mechanism (50, 54, 56) in accordance with the magnitude(s) of outside forces resisting rotation of the upper digit (48) and/or the lower digit (44) in order to preferentially apply movement to the digit experiencing lower resistance to movement; wherein the force balancing mechanism is arranged to increa

Abstract: A palm unit for an artificial hand comprises: a palm unit body (70); a motor (68) held by the palm unit body (70); a hydraulic pump assembly (72) held by the palm unit body (70) and comprising a low-pressure hydraulic pump (76) and a high-pressure hydraulic pump (74), wherein both hydraulic pumps (74, 76) are powered simultaneously by the motor (68); and a hydraulic circuit held by the palm unit body (70) and coupled to both hydraulic pumps (74, 76), wherein the hydraulic circuit has a low-pressure configuration in which the discharge sides of both hydraulic pumps (74, 76) a re coupled to one or more hydraulic actuator(s) (36, 38) for the artificial hand and a high-pressure configuration in which the discharge side of the low-pressure pump (76) is isolated from the hydraulic actuator(s) (36, 38) and recirculates fluid to the suction side of the low pressure pump (76) with the discharge side of the high-pressure pump (74) remaining coupled to the hydraulic actuator(s) (36, 38), and wherein the hydraulic circui

Abstract: A hydraulic pump assembly (72) comprises: a low-pressure hydraulic pump (74), a high-pressure hydraulic pump (76), and a drive shaft assembly (78) that passes along an axis of the pump assembly (72); wherein both hydraulic pumps (74, 76) are arranged to be rotated simultaneously by the drive shaft assembly (78); and wherein the pump assembly (72) is formed a single unit arranged to fit into a pump chamber (80).