Calibrated vision based robotic system
View Patent ↗A method of calibrating a vision based robotic system. The method includes engaging a calibration pin with a robotic tool and moving the calibration pin to a calibration block that includes at least one set of optical sensors having an optical transmitter to transmit an optical beam and an optical receiver to receive the optical beam. Further, the transmitted optical beam includes a center point. The method further includes: moving the calibration pin to the center point of the transmitted optical beam; determining a calibration pin center position relative to the robotic tool; and commanding a machine vision assembly having a camera to capture an image of a plurality of camera reading points of the calibration block and to determine a camera center position.
1. A method of calibrating a vision based robotic system comprising:
engaging a calibration pin with a robotic tool;
moving the calibration pin to a calibration block, the calibration block including at least one set of optical sensors having an optical beam transmitter to transmit an optical beam and an optical beam receiver to receive the optical beam, wherein the transmitted optical beam includes a center point;
moving the calibration pin to the center point of the transmitted optical beam of the calibration block;
determining, at a processor, a calibration pin center position relative to the robotic tool; and
commanding, by the processor, a machine vision assembly having a camera to capture an image of a plurality of camera reading points of the calibration block and to determine a camera center position.
2. The method of claim 1 , wherein the at least one set of optical sensors are in perpendicular alignment with one another such that the transmitted optical beam intersects at a center point.
3. The method of claim 1 , further comprising calculating a camera to tool offset value, the camera to tool offset value being calculated as the difference between the camera center position and the calibration pin center position.
4. The method of claim 3 , wherein the camera center position includes a pixel to distance calibration.
5. The method of claim 3 , wherein the camera center position is calculated by forming a geometric arrangement from the captured images of the camera reading points and calculating a center of the geometric arrangement.
6. The method of claim 3 , wherein the plurality of camera reading points include four holes on the calibration block that are aligned with the two sets of optical sensors, respectively, and the camera center position is calculated by capturing an image of each of the four holes to form a square and calculating a center of the square.
7. The method of claim 3 , wherein the robotic tool is one of a vacuum gripper or a three jaw gripper.
8. The method of claim 3 , further comprising:
utilizing the robotic tool as a pick and place station to engage a workpiece and to store the workpiece to a selected portion of a device;
aligning the workpiece with the robotic tool to the selected portion of the device based upon a captured image of the selected portion of the device from the machine vision assembly and the camera to tool offset value; and
moving the robotic tool to the device to place the aligned workpiece onto or into the selected portion of the device.
9. The method of claim 8 , wherein the device is a disk drive.
10. The method of claim 8 , wherein the workpiece is one of a head stack assembly, a ramp, or a disk.
11. A calibrated vision based robotic system comprising:
a robotic tool to engage a calibration pin;
a servo motor assembly configured to move the robotic tool;
a machine vision assembly including a camera;
a calibration block including a plurality of camera reading points and at least two sets of optical sensors, each set of optical sensors comprising an optical beam transmitter to transmit an optical beam and an optical beam receiver to receive the optical beam, wherein the two sets of optical sensors are in alignment with one another such that the transmitted optical beams intersect at a center point; and
a controller coupled to the servo motor assembly and the machine vision assembly, the controller operable to:
command the servo motor assembly to move the calibration pin to the center point of the transmitted optical beams of the calibration block;
determine a calibration pin center position relative to the robotic tool; and
command the camera to capture an image of the plurality of camera reading points and to determine a camera center position.
12. The robotic system of claim 11 , wherein the two sets of optical sensors are in perpendicular alignment with one another such that the transmitted optical beams intersect at a center point.
13. The robotic system of claim 11 , wherein the controller further calculates a camera to tool offset value, the camera to tool offset value being calculated as the difference between the camera center position and the calibration pin center position.
14. The robotic system of claim 13 , wherein the camera center position includes a pixel to distance calibration.
15. The robotic system of claim 13 , wherein the camera center position is calculated by forming a geometric arrangement from the captured images of the camera reading points and calculating a center of the geometric arrangement.
16. The robotic system of claim 13 , wherein the plurality of camera reading points include four holes on the calibration block that are aligned with the two sets of optical sensors, respectively, and the camera center position is calculated by capturing an image of each of the four holes to form a square and calculating a center of the square.
17. The robotic system of claim 13 , wherein the robotic tool is one of a vacuum gripper or a three jaw gripper.
18. The robotic system of claim 13 , wherein the robotic tool is utilized as a pick and place station to engage a workpiece and to store the workpiece to a selected portion of a device, the controller operable to control the servo motor assembly to move the robotic tool to: align the workpiece to the selected portion of the device based upon a captured image of the selected portion of the device from the machine vision assembly and the camera tool offset value and place the aligned workpiece onto or into the selected portion of the device.
19. The robotic system of claim 18 , wherein the device is a disk drive.
20. The robotic system of claim 18 , wherein the workpiece is one of a head stack assembly, a ramp, or a disk.
21. A calibrated vision based robotic system comprising:
a robotic tool to engage a calibration pin;
a servo motor assembly configured to move the robotic tool;
a machine vision assembly including a camera;
a calibration block including a plurality of camera reading points and at least two sets of optical sensors, each set of optical sensors comprising an optical beam transmitter to transmit an optical beam and an optical beam receiver to receive the optical beam, wherein the two sets of optical sensors are in perpendicular alignment with one another such that the transmitted optical beams intersect at a center point, and wherein the plurality of camera reading points include four holes on the calibration block that are aligned with the two sets of optical sensors; and
a controller coupled to the servo motor assembly and the machine vision assembly, the controller operable to:
command the servo motor assembly to move the calibration pin to the center point of the transmitted optical beams of the calibration block;
determine a calibration pin center position relative to the robotic tool; and
command the camera to capture an image of the plurality of camera reading points and to determine a camera center position, wherein the camera center position includes a pixel to distance calibration; and
calculate a camera to tool offset value, the camera to tool offset value being calculated as the difference between the camera center position and the calibration pin center position;
wherein the robotic tool is further utilized as a pick and place station to engage a workpiece and to store the workpiece to a selected portion of a device based upon a captured image of the selected portion of the device by the machine vision assembly and the camera tool offset value.
22. The robotic system of claim 21 , wherein the camera center position is calculated by capturing an image of each of the four holes to form a square and calculating a center of the square.
23. The robotic system of claim 21 , wherein the robotic tool is one of a vacuum gripper or a three jaw gripper.
24. The robotic system of claim 21 , wherein, the controller is operable to control the servo motor assembly to move the robotic tool to: align the workpiece to the selected portion of the device based upon a captured image of the selected portion of the device from the machine vision assembly and the camera tool offset value and place the aligned workpiece onto or into the selected portion of the device.
25. The robotic system of claim 24 , wherein the device is a disk drive.
26. The robotic system of claim 24 , wherein the workpiece is one of a head stack assembly, a ramp, or a disk.