Robot system and control method of robot system for taking out workpieces loaded in bulk

A robot system for taking out each of workpieces loaded in bulk inside a container, the robot system comprising:

• a hand including a plurality of claw parts and configured to grip the workpiece by using the claw parts;
• a robot configured to move the hand;
• a three-dimensional sensor configured to acquire information about a distance to the workpiece;
• and
• a controller configured to control the hand and the robot;
• wherein
• the claw parts include grip regions having a shape for gripping the workpiece,
• the controller includes
• an acquisition unit for acquiring three-dimensional information of the workpiece on the basis of an output of the three-dimensional sensor,
• a selection unit for selecting a target workpiece to be taken out by the robot, on the basis of the three-dimensional information of the workpiece,
• a collision detecting unit for stopping the robot in response to the hand colliding with the workpiece while the robot is moving to a target position for gripping the target workpiece,
• a position detecting unit for detecting a stop position of the robot stopped by the collision detecting unit,
• a determination unit for determining, on the basis of the target position and the stop position of the robot, whether or not the target workpiece is able to be pressed by a part other than the grip regions of the hand, and
• a movement control unit for controlling the robot so as to move the workpiece inside the container, and
• when the determination unit determines that the target workpiece is able to be pressed by the part other than the grip regions, the movement control unit controls the robot so as to move the hand in the horizontal direction without driving the claw parts, and press the workpiece by the hand.

A control method of a robot system including a robot and a hand provided with a plurality claw parts, for taking out each of workpieces loaded in bulk inside a container, the control method comprising:

• an image capturing step for capturing an image of the workpiece by using a three-dimensional sensor configured to acquire information about a distance to the workpiece;
• an acquisition step for acquiring three-dimensional information about the workpiece on the basis of an output of the three-dimensional sensor;
• a selection step for selecting a target workpiece to be taken out by the robot on the basis of the three-dimensional information of the workpiece;
• a stopping step for stopping the robot in response to the hand colliding with the workpiece while the robot is moving to a target position for gripping the target workpiece;
• a detection step for detecting a stop position of the robot stopped in the stopping step;
• a determination step for determining, on the basis of the target position and the stop position of the robot, whether or not the target workpiece is able to be gripped by a part other than grip regions of the hand, the grip regions having a shape for gripping the workpiece;
• and
• a movement step for controlling the robot so as to move the workpiece inside the container after the hand collides with the workpiece;
• wherein
• when it is determined in the determination step that the target workpiece is able to be gripped by the part other than the grip regions, the movement step includes a step for gripping the target workpiece by the hand and releasing the target workpiece after moving the target workpiece.

A control method of a robot system including a robot and a hand provided with a plurality claw parts, for taking out each of workpieces loaded in bulk inside a container, the control method comprising:

• an image capturing step for capturing an image of the workpiece by using a three-dimensional sensor configured to acquire information about a distance to the workpiece;
• an acquisition step for acquiring three-dimensional information about the workpiece on the basis of an output of the three-dimensional sensor;
• a selection step for selecting a target workpiece to be taken out by the robot on the basis of the three-dimensional information of the workpiece;
• a stopping step for stopping the robot in response to the hand colliding with the workpiece while the robot is moving to a target position for gripping the target workpiece;
• a detection step for detecting a stop position of the robot stopped in the stopping step;
• a determination step for determining, on the basis of the target position and the stop position of the robot, whether or not the target workpiece is able to be pressed by a part other than grip regions of the hand, the grip regions having a shape for gripping the workpiece;
• and
• a movement step for controlling the robot so as to move the workpiece inside the container after the hand collides with the workpiece;
• wherein
• when it is determined in the determination step that the target workpiece is able to be pressed by the part other than the grip regions, the movement step includes a step for controlling the robot so as to move the hand in the horizontal direction without driving the claw parts, and press the workpiece by the hand.