Apparatus for determining pickup pose of robot arm with camera

• US 8,406,923 B2
• Filed: 03/11/2009
• Issued: 03/26/2013
• Est. Priority Date: 03/12/2008
• Status: Expired due to Fees

• Current Assignee: Denso PS Corporation (DENSO Corporation)
• Original Assignee: Denso PS Corporation (DENSO Corporation)
• Inventors: Ueyama, Tsuyoshi, Takahashi, Minoru
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): Amin, Bhavesh V
• Application Number:
  US12/382,228
• Publication Number:
  US 20090234502A1
• Time in Patent Office: 1,476 Days
• Field of Search: None
• US Class Current: 700/259
• CPC Class Codes: B25J 19/023 including video camera means
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• CPC Class Codes: G05B 19/401 characterised by control arrangements for measuring, e.g. calibration and initialisation, measuring workpiece for machining purposes G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/37017 Calibration of vision system, set correct attidude of sensor to workpiece
• CPC Class Codes: G05B 2219/37208 Vision, visual inspection of workpiece

Abstract

In an apparatus, a coordinate obtaining unit drives a robot to move a camera opposing a workpiece in a first direction such that the workpiece is captured in an FOV of the camera. The coordinate obtaining unit obtains second and third coordinates of a preset point of the robot arm in respective second and third axes of a three-dimensional coordinate system with the workpiece being captured in the FOV. The first, second, and third coordinates are defined as coordinates of a temporally defined reference point of the workpiece in the three-dimensional coordinate system. A pose determining unit drives, at a given timing, the robot arm to determine a pose of the preset point based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm.

Claims

1. An apparatus for determining, in a three-dimensional coordinate system, a pickup pose of a robot arm with a camera when an image of a workpiece is to be picked up by the camera, the workpiece being mounted on a reference plane, the apparatus comprising:

an input unit configured to input a first coordinate of the workpiece in a first axis of the three-dimensional coordinate system, the first axis being defined as orthogonal to the reference plane;

a coordinate obtaining unit configured to;

drive the robot to move the camera opposing the workplace in the first direction such that at least part of the workplace is captured in a field of view of the camera; and

obtain second and third coordinates of a preset point of the robot arm in respective second and third axes of the three-dimensional coordinate system with the at least part of the workpiece being captured in the field of view of the camera, the second and third axes being orthogonal to the first axis, the first, second, and third coordinates being defined as coordinates of a temporally defined reference point of the work piece in the three-dimensional coordinate system, the coordinate obtaining unit comprising;

a first driving unit configured to drive the robot to move the camera opposing the workpiece in the first direction such that the at least part of the workpiece is captured in the field of view of the camera;

a specifying unit configured to specify a desired point on the workpiece as the temporally defined reference point;

a second driving unit configured to drive the robot to move the camera such that the optical axis of the camera passes through the specified point; and

an obtaining unit configured to obtain the second and third coordinates of the preset point of the robot arm in the respective second and third axes of the three-dimensional coordinate system with the optical axis of the camera passing through the specified point; and

a pose determining unit configured to drive, at a given timing, the robot arm to determine a pose of the preset point of the robot arm based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm, wherein the specifying unit is configured to;

pick up and display an image of the workpiece with the at least part of the workpiece being captured in the field of view of the camera; and

specify a dot on the displayed image of the workpiece, the specified dot corresponding to the specified point on the workpiece as the temporally defined reference point.

2. The apparatus according to claim 1, wherein the pose determining unit is configured to drive, at a given timing, the robot arm to determine the pose of the preset point of the robot arm based on the positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm such that an optical axis of the camera is directed to the temporally defined reference point of the workpiece.

3. The apparatus according to claim 1, wherein the specified dot is arranged at a substantial center of the displayed image of the workpiece.

4. An. apparatus for determining, in a three-dimensional coordinate system, a pickup pose of a robot arm with a camera when an image of a workpiece is to be picked up by the camera, the workpiece being mounted on a reference plane, the apparatus comprising:

an input unit configured to input a first coordinate of the workpiece in a first axis of the three-dimensional coordinate system, the first axis being defined as orthogonal to the reference plane;

a coordinate obtaining unit configured to;

drive the robot to move the camera opposing the workpiece in the first direction such that at least part of the workpiece is captured in a field of view of the camera; and

obtain second and third coordinates of a preset point of the robot arm in respective second and third axes of the three-dimensional coordinate system with the at least part of the workpiece being captured in the field of view of the camera, the second and third axes being orthogonal to the first axis, the first, second, and third coordinates being defined as coordinates of a temporally defined reference point of the workpiece in the three-dimensional coordinate system, the coordinate obtaining unit comprising

a first driving unit configured to drive the robot to move the camera opposing the workpiece in the first direction such that the at least part of the workpiece is captured in the field of view of the camera;

a specifying unit configured to specify a plurality of desired points on the workpiece; and

a second driving unit configured to drive the robot to move the camera such that the optical axis of the camera passes through each of the plurality of specified points; and

an obtaining unit configured to;

obtain coordinates of the preset point of the robot arm in the respective second and third axes of the three-dimensional coordinate system with the optical axis of the camera passing through each of the plurality of specified points; and

determine, as the second and third coordinates of the preset point of the robot arm, coordinates of a center of a figure, the figure being formed by connecting the coordinates of the preset point of the robot arm for the respective specified points; and

a pose determining unit configured to drive, at a given timing, the robot arm to determine a pose of the preset point of the robot arm based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm, wherein;

the specifying unit is configured to;

pick up and display an image of the workpiece with the at least part of the workpiece being captured in the field of view of the camera; and

specify a plurality of dots on or around the displayed image of the workpiece, the plurality of specified dots corresponding to the plurality of specified points, respectively.

5. An apparatus for determining, in a three-dimensional coordinate system, a pickup pose of a robot arm with a camera when an image of a workpiece is to be picked up by the camera, the workpiece being mounted on a reference plane, the apparatus comprising:

an input unit configured to input a first coordinate of the workpiece in a first axis of the three-dimensional coordinate system, the first axis being defined as orthogonal to the reference plane;

a coordinate obtaining unit configured to;

drive the robot to move the camera opposing the workpiece in the first direction such that at least part of the workpiece is captured in a field of view of the camera; and

obtain second and third coordinates of a preset point of the robot arm in respective second and third axes of the three-dimensional coordinate system with the at least part of the workpiece being captured in the field of view of the camera, the second and third axes being orthogonal to the first axis, the first, second, and third coordinates being defined as coordinates of a temporally defined reference point of the workpiece in the three-dimensional coordinate system, the coordinate obtaining unit comprising;

a first driving unit configured to drive the robot to move the camera opposing the workpiece in the first direction such that the at least part of the workpiece is captured in the field of view of the camera;

a specifying unit configured to specify a plurality of desired points on the workpiece as the plurality of temporally defined reference points; and

a second driving unit configured to drive the robot to move the camera such, that the optical axis of the camera passes through each of the plurality of specified points; and

an obtaining unit configured to obtain the second and third coordinates of the preset point of the robot arm in the respective second and third axes of the three-dimensional coordinate system with the optical axis of the camera passing through each of the plurality of specified points, the first, second, and third coordinates for each of the plurality of specified points being defined as coordinates of a corresponding one of the plurality of temporally defined reference points of the workpiece in the three-dimensional coordinate system; and

a pose determining unit configured to drive, at a given timing, the robot arm to determine a pose of the preset point of the robot arm based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm, wherein the temporally defined reference point is a plurality of temporally defined reference points, and

wherein the specifying unit is configured to;

pick up and display an image of the workpiece with the at least part of the workpiece being captured in the field of view of the camera; and

specify a plurality of dots on the displayed image of the workpiece, the plurality of specified dots corresponding to the plurality of specified points, respectively.

6. An apparatus for determining, in a three-dimensional coordinate system, a pickup pose of a robot arm with a camera when an image of a workpiece is to be picked up by the camera, the workpiece being mounted on a reference plane, the apparatus comprising:

an input unit configured to input a first coordinate of the workpiece in a first axis of the three-dimensional coordinates stem the first axis being defined as orthogonal to the reference plane;

a coordinate obtaining unit configured to;

drive the robot to move the camera opposing the workpiece in the first direction such that at least part of the workpiece is captured in a field of view of the camera; and

obtain second and third coordinates of a preset point of the robot arm in respective second and third axes of the three-dimensional coordinate system with the at least part of the workpiece being captured in the field of view of the camera, the second and third axes being orthogonal to the first axis, the first second, and third coordinates being defined as coordinates of a temporally defined reference point of the workpiece in the three-dimensional coordinate system the coordinate obtaining unit comprising;

a first driving unit configured to drive the robot to move the camera opposing the workpiece in the first direction such that the at least part of the workpiece is captured in the field of view of the camera;

a specifying unit configured to specify a plurality of groups of desired points on the workpiece; and

a second driving unit configured to drive the robot to move the camera such that the optical axis of the camera passes through each of the plurality of groups of specified points; and

an obtaining unit configured to;

obtain coordinates of the preset point of the robot arm in the respective second and third axes of the three-dimensional coordinate system with the optical axis of the camera passing through each of the plurality of groups of specified points; and

determine coordinates of a center of each of a first figure and a second figure, the first figure being formed by connecting the coordinates of the preset point of the robot arm for the respective specified points of the first group, the second figure being formed by connecting the coordinates of the preset point of the robot arm for the respective specified points of the second group, the coordinates of the center of each of the first and second figures representing the second and third coordinates of the reset point of the robot arm for a corresponding one of the plurality of temporarily defined points; and

a pose determining unit configured to drive, at a given timing, the robot arm to determine a pose of the preset point of the robot arm based on a positional relationship between the first, second, and third coordinates of the temporally defined reference point of the workpiece and actual coordinates of the preset point of the robot arm, wherein the temporally defined reference point is a plurality of temporally defined reference points, and

wherein the specifying unit is configured to;

pick up and display an image of the workpiece with the at least part of the workpiece being captured in the field of view of the camera; and

specify a plurality of groups of dots on or around the displayed image of the workpiece, the plurality of groups of specified dots corresponding to the plurality of groups of specified points, respectively.