Method for measuring three-dimensional position of object to be captured and method for capturing the object

• US 5,280,436 A
• Filed: 04/17/1991
• Issued: 01/18/1994
• Est. Priority Date: 04/18/1990
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Anezaki, Takashi, Inoue, Hiroyuki, Kubota, Hitoshi, Yamane, Manabu, Maruo, Tomohiro
• Primary Examiner(s): Cosimano, Edward R.
• Application Number:
  US07/686,390
• Time in Patent Office: 1,007 Days
• Field of Search: 33/297, 356/375, 364/559, 382/8, 901/47
• US Class Current: 700/302
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• CPC Class Codes: G01S 17/46 Indirect determination of position data
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G05B 2219/36404 Adapt teached position as function of deviation 3-D, 2-D position workpiece
• CPC Class Codes: G05B 2219/37275 Laser, interferometer
• CPC Class Codes: G05B 2219/40621 Triangulation sensor
• CPC Class Codes: G05B 2219/45034 Adjusting, trimming circuits on printed boards

Abstract

A method for measuring the three-dimensional position of an object to be captured. A laser measuring unit is provided having an image recognition camera confronting the object, first and second laser light emitting sources respectively irradiating from a slant direction a lateral slit light onto the object relative to a vertical axis of a vision coordinate system and irradiating a vertical slit light onto the object relative to a lateral axis of the vision coordinate system, one slit image on the vertical axis of the object and one slit image on the lateral axis of the object and one of the slit images on the vertical and lateral axes formed before and after the laser measuring unit is moved a predetermined amount in a direction of a camera optical axis relative to the object are taken into the camera, and the three-dimensional position is calculated from the relationship between the predetermined moving distance amount and the deviation of the slit images on the vision coordinates of the coordinate system. This method can be used to locate an electric adjustment position of an electronic component and to move the hand of an industrial robot carrying an electric adjustment member to the electronic component for adjusting the electronic component in the electric adjustment position.

Claims

1. A method for measuring a three-dimensional position of an object to be captured comprising providing a laser measuring unit having an image recognition camera confronting the object and a first and a second laser emitting light source, emitting from the first laser emitting light source laser light for irradiating a lateral slit light onto the object from a slant direction relative to a vertical axis of a vision coordinate system, and emitting from the second laser emitting light source further laser light for irradiating a vertical slit light from a slant direction relative to a lateral axis of the vision coordinate system, one slit image on the vertical axis of the object and one slit image on the lateral axis thereof and one of the slit images on the vertical and lateral axes thereof formed before and after the laser measuring unit is moved a predetermined amount in a direction of a camera optical axis relative to the object are taken into the camera, and calculating the three-dimensional position of the object from the relationship between a predetermined moving amount of the laser measuring unit and deviation of the slit images on vision coordinates of the coordinate system.

2. A method for measuring a three-dimensional position of an electronic component to be captured by an electric adjustment member at an electric adjustment position of the electronic component, comprising the steps of:

providing in a control of a servo-driven industrial robot an initial position of an electric adjustment member mounted on a hand portion of the industrial robot;

calculating, as an electric adjustment position for the electronic component, the three-dimensional position of the electronic component to be captured by said electric adjustment member and mounted on a workpiece, said calculating step being constituted by providing a laser measuring unit having an image recognition camera confronting the electronic component and a first and second laser emitting light source, emitting from the first laser emitting light source laser light for irradiating a lateral slit light onto the electronic component from a slant direction relative to a vertical axis of a vision coordinate system, and emitting from the second laser emitting light source further laser light for irradiating a vertical slit light onto the electronic component from a slant direction relative to a lateral axis of the vision coordinate system, one slit image on the vertical axis of the electronic component and one slit image on the lateral axis thereof and one of the slit images on the vertical and lateral axes thereof formed before and after the laser measuring unit is moved a predetermined amount in a direction of a camera optical axis relative to the object are taken into the camera, and calculating the three-dimensional position of the electronic component from the relationship between a pre-taught moving distance of the laser measuring unit and deviation of the slit images on vision coordinates of the coordinate system;

compensating the initial position of the electric adjustment member on the hand portion of the industrial robot by the amount of deviation of the electric adjustment position of the electronic component from the initial position so as to move the electric adjustment member to the electric adjustment position of the electronic component.

3. The method as claimed in claim 2 further comprising the steps of:

providing at least two claws with tapered portions and movable between closed and open states for capturing an electronic component by holding an end face of the electronic component onto the electric adjustment member mounted on the hand portion of the industrial robot;

moving the electric adjustment member according to the deviation of the electric adjustment position of the electronic component to the electric adjustment position of the electronic component with the claws normally closed;

causing the claws to be opened as they are moved over end edges of the electronic component after contact of the tapered portions therewith and then to be closed at a final capturing position after the tapered portions have passed the end edges;

detecting the closed state and open state of the capturing claws as the tapered portions thereof are moved over end edges of the electronic component;

stopping movement of the industrial robot when all of the capturing claws have been detected as having been shifted from the closed state through the open state to the closed state again; and

determining the position of the industrial robot when all of the capturing claws have reached the closed state again as the captured position of the electronic component.

4. The method as claimed in claim 3 further comprising the steps of:

cutting off a servo power source for only the axis of the industrial robot perpendicular to the end face of the electronic component when the industrial robot is determined to be at the captured position so as to release stress on the electronic adjustment member and the hand portion of the industrial robot at the captured position so that the industrial robot is in a state free from servo control as to said axis; and

determining the position of the industrial robot in the servo-free state as the final captured position of the electronic component, and servo-locking the servo power source for said axis of the industrial robot.