Tactile sensor module for robot-hand and grasping method using the same

A robot-hand, comprising:

• a plurality of fingers, each having a tactile sensor module and a plurality of phalange sensor modules rotatably coupled by link members;
• and
• a base connected with the plurality of fingers by a base link member and having a hand back control unit for controlling a grasping motion of the finger, the base having a cover plate installed at an outer surface thereof,
• wherein the tactile sensor module is configured to measure a normal force applied when the robot-hand is grasping an object,
• the phalange sensor module has an actuator to generate a driving force for a grasping motion and is configured to measure the normal force and a rotational displacement of a motor of the actuator when the robot-hand is grasping the object, and
• the hand back control unit is configured to control a grasping force by receiving the normal force data and rotational displacement data from the tactile sensor module and the phalange sensor module.

A grasping method for grasping an object using a robot-hand having a tactile sensor module at a finger, the grasping method comprising:

• generating a velocity command in a grasping direction so that the tactile sensor module contacts the object, and grasping the object by the robot-hand;
• determining whether any force sensor provided to the tactile sensor module is activated as a normal force over a threshold value is applied to the force sensor;
• counting a number of activated force sensors;
• determining whether the number of activated force sensors is greater than a predetermined value;
• maintaining a grasping motion of the robot-hand during a predetermined time;
• generating a velocity command in a reverse grasping direction to decrease a grasping force of the robot-hand;
• and
• determining whether the number of activated force sensors is equal to the predetermined value.