Pneumatic, tactile gripper generating a gripping force controlled by the weight of the handled object

A multi-digital gripper to seize and maneuver objects, comprising at least one movable finger (5) driven by a pneumatic jack or actuator (1) of which the two internal chambers (1a, 1b) are connected by feed lines (R1, R2 and R'2) to at least one supply source (S1, S2, S'2), wherein each movable finger comprises:

• a flexible blade (4) solidly joined to the movable member (2) of the actuator (1) so that a free portion of said blade can bend in a direction (.DELTA.) perpendicular to its longitudinal axis, a stop member (5) fastened to the free end of the blade (4) and having a contact surface (5a) that will come to rest against the object to be seized, proximity sensors (7) for the object to be seized and distribution means (6) for the fluid flow to each chamber (1a, 1b) of the actuator (1), said distribution means being controlled by the sensors and being designed to:
• (a) command a relative pressure difference for the two chambers (1a, 1b) of the actuator to drive the movable member (2) of the actuator (1) in the absence of contact between the stop member (5) and the object to be seized,
• (b) command an approximate re-balancing of the relative pressures of the two actuator chambers in the presence of contact between the stop member (5) and the object to be seized,
• at least one pneumatic potentiometer (9) consisting of a fluid container provided with a feed intake (9a) connected to a source (S2) of fluid, of a nozzle provided with a leakage aperture (9c) and a fluid outlet (9b) connected to a chamber (1a) of the actuator (1), the leakage aperture (9c) of said potentiometer being located opposite the free portion of the flexible blade (4) so as to obtain a pneumatic magnitude directly related to the blade bending at the potentiometer outlet (9b).