POSITION DETECTION DEVICE FOR ROBOT, ROBOTIC SYSTEM, AND POSITION DETECTION METHOD FOR ROBOT

• US 20120209430A1
• Filed: 02/14/2012
• Published: 08/16/2012
• Est. Priority Date: 02/15/2011
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: IGARASHI, Katsuji, ASADA, Atsushi, SETSUDA, Nobuyuki, IUCHI, Chieko
• Granted Patent: US 9,457,472 B2
• Time in Patent Office: Days
• US Class Current: 700/259
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• CPC Class Codes: G05B 2219/39397 Map image error directly to robot movement, position with relation to world, base not needed, image based visual servoing

Abstract

A position detection device for a horizontal articulated robot includes a camera for imaging the robot or a work as an imaging object, a control section for calculating a location of the imaging object from an image, an acquisition section (I/O) for obtaining the drive amounts of first and second electric motors of the robot, and a storage section for storing the calculated location of the imaging object and the drive amounts so as to correspond to each other. A common trigger signal for detecting the location of the imaging object is input to the camera and the I/O. The camera starts to image the imaging object in response to the input of the trigger signal. The I/O starts to obtain the drive amounts in response to the input of the trigger signal.

Claims

1. A position detection device for a robot comprising:

an imaging section adapted to image at least one of the robot and a work held by the robot as an imaging object during movement of the robot;

a calculation section adapted to calculate a location of the imaging object from an image taken by the imaging section;

an acquisition section adapted to obtain a drive amount of a drive source of the robot; and

a storage section adapted to store the calculated location of the imaging object and the drive amount so as to correspond to each other,

wherein a common trigger signal for triggering the detection of the location of the imaging object is input to the imaging section and the acquisition section,

the imaging section starts to image the imaging object in response to the trigger signal, and

the acquisition section starts to obtain the drive amount in response to the trigger signal.

2. The position detection device for a robot according to claim 1, further comprising:

a command output section adapted to detect whether one of the robot and the work held by the robot as a detection object reaches a predetermined position, and then output the common trigger signal to the imaging section and the acquisition section in response to the detection object reaching the predetermined position.

3. The position detection device for a robot according to claim 2, wherein

the detection object corresponds to the imaging object of the imaging section, and

the command output section detects whether the detection object reaches an imaging area of the imaging section.

4. The position detection device for a robot according to claim 1, wherein

the imaging object corresponds to the work, and

an end effector adapted to grip the work is optically shielded by the work with respect to the imaging section in an imaging area of the imaging section.

5. The position detection device for a robot according to claim 1, wherein

the storage section stores a target position of the imaging object and the drive amount of the drive source so as to correspond to each other, and

the position detection device further comprises:

a correction section adapted to correct a correspondence relationship between the target position and the drive amount for reaching the target position based on a correspondence relationship between the calculated location and the drive amount stored in the storage section.

6. A robotic system comprising:

a robot adapted to convey a work; and

a position detection device for the robot, the position detection device being adapted to detect one of a location of the robot and a location of the work conveyed by the robot,

wherein the position detection device for the robot comprises the position detection device for a robot according to claim 1.

7. A robotic system comprising:

a robot adapted to convey a work; and

a position detection device for the robot, the position detection device being adapted to detect one of a location of the robot and a location of the work conveyed by the robot,

wherein the position detection device for the robot comprises the position detection device for a robot according to claim 2.

8. A robotic system comprising:

a robot adapted to convey a work; and

a position detection device for the robot, the position detection device being adapted to detect one of a location of the robot and a location of the work conveyed by the robot,

wherein the position detection device for the robot comprises the position detection device for a robot according to claim 3.

9. A robotic system comprising:

a robot adapted to convey a work; and

a position detection device for the robot, the position detection device being adapted to detect one of a location of the robot and a location of the work conveyed by the robot,

wherein the position detection device for the robot comprises the position detection device for a robot according to claim 4.

10. A robotic system comprising:

a robot adapted to convey a work; and

a position detection device for the robot, the position detection device being adapted to detect one of a location of the robot and a location of the work conveyed by the robot,

wherein the position detection device for the robot comprises the position detection device for a robot according to claim 5.

11. A position detection method for a robot comprising:

imaging at least one of the robot and a work held by the robot as an imaging object during movement of the robot;

calculating a location of the imaging object from an image taken in the imaging;

obtaining a drive amount of a drive source of the robot; and

storing the calculated location of the imaging object and the drive amount so as to correspond to each other,

wherein the imaging step and the obtaining step start in response to a common trigger signal for triggering the detection of the location of the imaging object.