Method for producing a precision 3-D measuring apparatus

• US 6,015,473 A
• Filed: 11/01/1996
• Issued: 01/18/2000
• Est. Priority Date: 08/07/1995
• Status: Expired due to Term

• Current Assignee: Immersion Corporation
• Original Assignee: Immersion Corporation
• Inventors: Schena, Bruce M., Rosenberg, Louis B., Brave, Scott B., Jackson, Bernard G.
• Primary Examiner(s): Maki, Steven D.
• Application Number:
  US08/744,725
• Time in Patent Office: 1,173 Days
• Field of Search: 156/60, 156/293, 156/294, 156/296, 156/423, 156/305, 901/15, 901/28, 702/95
• US Class Current: 156/293
• CPC Class Codes: A63F 2300/1037 being specially adapted for converting control signals received from the game device into a haptic signal, e.g. using force feedback
• CPC Class Codes: B25J 9/1692 Calibration of manipulator
• CPC Class Codes: G01B 21/04 by measuring coordinates of points
• CPC Class Codes: G01B 21/042 Calibration or calibration artifacts G01B3/30, G01B9/02072 take precedence
• CPC Class Codes: G01B 5/008 using coordinate measuring machines
• CPC Class Codes: G05B 19/4207 in which a model is traced or scanned and corresponding data recorded
• CPC Class Codes: G05B 2219/37021 Robot controls position of touch probe
• CPC Class Codes: G05B 2219/37043 Touch probe, store position of touch point on surface
• CPC Class Codes: G05B 2219/39015 With different manipulator configurations, contact known sphere, ballbar
• CPC Class Codes: G05B 2219/39021 With probe, touch reference positions
• CPC Class Codes: G05B 2219/39024 Calibration of manipulator
• CPC Class Codes: G05B 2219/39048 Closed loop kinematic self calibration, grip part of robot with hand
• CPC Class Codes: G05B 2219/45055 Assembly
• CPC Class Codes: G05B 2219/45061 Measuring robot
• CPC Class Codes: G06F 2203/015 Force feedback applied to a joystick
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: H01H 2003/008 with a haptic or a tactile feedback controlled by electrical means, e.g. a motor or magnetofriction

Abstract

A method for assembling a linkage assembly for a 3-D Digitizing Probe Apparatus. A linkage assembly for incorporation into the probe apparatus includes a linkage and a joint member provided at each end of the linkage. Joint fixtures for receiving and holding the joints are provided at a desired distance and orientation apart. The joint members are loosely coupled to the linkage and are moved relative to the linkage so that the joint members fit in the joint fixtures and so that the linkage provides a desired length between the joints. The joint members are bonded to the linkage while the assembly is in the fixtures, thus fastening the components of the assembly together with minimal stress to the assembly and providing a precise linkage length and orientation of joints in the assembly.

Claims

1. A method for assembling a linkage assembly of a probe apparatus for measuring three-dimensional coordinates and for calibrating the probe apparatus, the linkage assembly including a plurality of rotatable joint members and a linkage, the method comprising:

providing two joint fixtures positioned a precise distance apart and having a precise predetermined orientation with respect to each other, each of said fixtures for receiving and holding one of said rotatable joint members of said linkage assembly;

loosely connecting a portion of each of said rotatable joint members to an associated end of a linkage so that said portions of said joint members can each be moved along said linkage to different positions at said end of said linkage;

moving said loosely connected portion of said rotatable joint member along said linkage to one of said positions to provide a distance between said portions of said joint members that allows each of said joint members to fit in a respective joint fixture;

placing and holding each of said joint members of said linkage assembly in an associated one of said joint fixtures such that said linkage has a precise desired length between said portions of said joint members;

bonding said portions of said joint members to said linkage while said joint members are held in said joint fixtures, thereby providing joints at both ends of said linkage at a precise distance apart from each other;

including said linkage assembly in said probe apparatus; and

calibrating said probe apparatus which includes said joint linkage assembly and a probe, wherein said calibrating includes positioning said probe at an arbitrary location within a selected volume, sampling a plurality of orientations of said probe at said arbitrary location, and determining calibration parameters based on error values determined between said sampled orientations, wherein said calibration parameters are used when determining a position and orientation of said probe during use of the probe apparatus.

2. A method as recited in claim 1 wherein said linkage is made of graphite.

3. A method as recited in claim 1 wherein said joint members are positioned in said joint fixtures relative to each other as would allow rotation by each of said joint members in a single plane when not held by said joint fixtures.

4. A method as recited in claim 1 wherein each of said portions is an extended portion of the joint member for receiving an end of said linkage.

5. A method as recited in claim 1 wherein said two joint fixtures are coupled together by a rigid member.

6. A method as recited in claim 1 wherein each of said joint members is configured to enclose a sensor device for measuring rotation of said joint member.

7. A method for precisely assembling a joint-linkage assembly of a probe apparatus used for measuring three-dimensional coordinates and for calibrating the probe apparatus, the method comprising:

providing two joint fixtures at a predetermined precise distance apart from each other and having a predetermined precise orientation with respect to each other, said joint fixtures being connected together by a support member, wherein said predetermined distance is a desired length of a portion of an arm in said probe apparatus;

providing a joint-linkage assembly, said assembly including a linkage and a portion of a rotatable joint member loosely coupled at each of said linkage;

adjusting at least one of said member portions relative to said linkage by moving said at least one joint member portion along said linkage until said joint member portions are at a distance apart as to allow the joint members to fit in said fixtures;

placing said joint-linkage assembly in said fixtures such that said joint members are held at said predetermined precise distance apart and at said precise orientation with respect to each other;

bonding said joint member portions to said linkage while said joint-linkage assembly is held in said joint fixtures;

including said joint-linkage assembly in said probe apparatus and

calibrating said probe apparatus which includes said joint linkage assembly and a probe, wherein said calibrating includes positioning said probe at an arbitrary location within a selected volume, sampling a plurality of orientations of said probe at said arbitrary location, and determining calibration parameters based on error values determined between said sampled orientations, wherein said calibration parameters are used when determining a position and orientation of said probe during use of the probe apparatus.

8. A method as recited in claim 7 wherein said linkage is made of graphite.

9. A method as recited in claim 7 wherein each of said joint members is configured to enclose a sensor device for measuring rotation of said joint member.

10. A method as recited in claim 7 wherein said joint members are positioned in said joint fixtures relative to each other as would allow rotation by each of said joint members in a single plane when not held by said joint fixtures.

11. A method for assembling a joint-linkage assembly of a probe apparatus coupled to a computer system, and for calibrating the probe apparatus, said joint-linkage assembly including two rotatable joint members and a linkage coupled to said joint members, said probe apparatus for measuring three-dimensional coordinates and including a probe moveable within a selected volume, and wherein sensors coupled to said joint-linkage assembly are operative to sense joint angles related to a position and orientation of said probe and provide joint angle data to said computer system, the method comprising:

providing two joint fixtures positioned a precise distance apart, each of said fixtures being adapted to receive and hold a portion of one of said rotatable joint members of said joint-linkage assembly, wherein said precise distance is a desired length of a portion of an arm in said probe apparatus;

adjusting at least one of said joint members relative to said linkage by moving said joint member along said linkage until said joint members are at a distance apart so as to allow said joint members to fit in said fixtures, and placing said joint-linkage assembly in said fixtures such that said joint member portions are held at said predetermined precise distance apart;

bonding said joint members to said linkage while said joint members are held in said joint fixtures, thereby providing joints at both ends of said linkage at a precise distance apart; and

including said joint linkage assembly in said probe apparatus and calibrating said probe apparatus, wherein said calibrating includes positioning said probe at an arbitrary location within said selected volume, sampling a plurality of orientations of said probe at said arbitrary location, and determining calibration parameters based on error values determined between said sampled orientations, wherein said calibration parameters are used when determining a position and orientation of said probe during use of said probe apparatus.

12. A method as recited in claim 11 wherein a known point on said probe is maintained at said arbitrary location while varying said orientation of said probe to move the joints of said joint linkage assembly and while sampling said plurality of orientations.

13. A method as recited in claim 12 wherein spatial coordinates are determined for said known point on said probe at each of said plurality of orientations, and determining said error values between said spatial coordinates.

14. A method as recited in claim 11 wherein said rotatable joint members are moved such that said joint members fit in said fixtures.