Robot hand and robot

A robot comprising a robot hand, the robot hand includes a plurality of fingers and a base provided with the plurality of fingers and grasps an object by using the plurality of fingers, the robot hand comprising:

• a resultant reaction force detector that detects a resultant reaction force that is a combination of reaction forces exerted by the plurality of fingers on the base;
• and
• a finger driver that drives the plurality of fingers to approach the object or move away from the object, wherein the plurality of fingers include a contact sensing finger that senses contact with the object, and
• the finger driver moves the plurality of fingers toward the object when the resultant reaction force is not detected and the contact sensing finger does not sense the contact, and
• switches a force that drives the plurality of fingers to a force corresponding to a grasp force exerted to grasp the object when the contact sensing finger senses the contact, and
• wherein, when the contact sensing finger does not sense the contact but the resultant reaction force is detected, the driving of the plurality of fingers is stopped, the position of the base is changed by moving the base in a direction in which the resultant reaction force is not detected any more, and the plurality of fingers are again moved toward the object.

A method of controlling a robot hand that includes a plurality of fingers and a base provided with the plurality of fingers and grasps an object by using the plurality of fingers, the method comprising:

• providing the plurality of fingers with a contact sensing finger that senses contact with the object,
• detecting a resultant reaction force that is a combination of reaction forces exerted by the plurality of fingers on the base;
• and
• driving the plurality of fingers to approach the object or move away from the object,
• the driving step including:
• moving the plurality of fingers toward the object when the resultant reaction force is not detected and the contact sensing finger does not sense the contact, and
• switching a force that drives the plurality of fingers to a force corresponding to a grasp force exerted to grasp the object when the contact sensing finger senses the contact, and
• wherein, when the contact sensing finger does not sense the contact but the resultant reaction force is detected:
• stopping the driving of the plurality of fingers;
• changing the position of the base by moving the base in a direction in which the resultant reaction force is not detected any more;
• and
• thereafter moving the plurality of fingers toward the object.