Automated robotic measuring system

• US 7,441,341 B2
• Filed: 12/21/2006
• Issued: 10/28/2008
• Est. Priority Date: 01/14/2004
• Status: Expired due to Term

• Current Assignee: Romer Incorporated (Hexagon AB)
• Original Assignee: Romer Incorporated (Hexagon AB)
• Inventors: Eaton, Homer
• Primary Examiner(s): Bennett; G. Bradley
• Assistant Examiner(s): Johnson; Amy Cohen
• Application Number:
  US11/614,932
• Publication Number:
  US 20070163136A1
• Time in Patent Office: 677 Days
• Field of Search: 335/03, 33/1.M, 73/17.9, 414/680, 414/735, 901/15, 901/28, 7449001-49006, 31856811-56821, 318/568.25, 700/245, 301/15, 301/18, 31556811-56821, 315/568.25
• US Class Current: 33/503
• CPC Class Codes: G01B 5/004 for measuring coordinates of points
• CPC Class Codes: Y10T 74/20329 Joint between elements

Abstract

An automated coordinate measuring system comprising a measuring arm used for acquisition of geometry data that incorporates an exoskeletal structure resilient to physical perturbations including thermal changes and vibrations which may affect coordinate data acquisition. The system may be adapted to a portable platform allowing for convenient positioning and alignment of the measuring arm in a wide variety of environments.

Claims

1. A positioning system comprising:

an articulated supporting arm comprising a plurality of jointedly interconnected support arm segments moveable about a plurality of axes;

a plurality of compliant members positioned on said supporting arm;

an articulated measuring arm comprising a plurality of jointedly interconnected measuring arm segments capable of a plurality of degrees of freedom of movement and supported by said compliant members wherein said compliant members provide a yielding characteristic that resists a degree of compressibility of each compliant member when a force is applied to one of the articulated supporting arm and the articulated measuring arm; and

at least one alignment detector configured to detect the alignment between the articulated supporting arm and the articulated measuring arm, wherein the alignment detector comprises at least one encoder configured to measure the angular displacement between the articulated supporting arm and the articulated measuring arm.

2. A positioning system comprising:

an articulated supporting arm comprising a plurality of jointedly interconnected support arm segments moveable about a plurality of axes;

a plurality of compliant members positioned on said supporting arm;

an articulated measuring arm comprising a plurality of jointedly interconnected measuring arm segments capable of a plurality of degrees of freedom of movement and supported by said compliant members wherein said compliant members provide a yielding characteristic that resists a degree of compressibility of each compliant member when a force is applied to one of the articulated supporting arm and the articulated measuring arm; and

at least one alignment detector configured to detect the alignment between the articulated supporting arm and the articulated measuring arm, wherein the alignment detector comprises a first encoder for detecting angular displacement in a selected support arm segment of the articulated supporting arm and a second encoder for detecting angular displacement of a selected measuring arm segment in the articulated measuring arm.

3. A positioning system comprising:

an articulated supporting arm comprising a plurality of jointedly interconnected support arm segments moveable about a plurality of axes;

a plurality of compliant members positioned on said supporting arm;

an articulated measuring arm comprising a plurality of jointedly interconnected measuring arm segments capable of a plurality of degrees of freedom of movement and supported by said compliant members wherein said compliant members provide a yielding characteristic that resists a degree of compressibility of each compliant member when a force is applied to one of the articulated supporting arm and the articulated measuring arm; and

at least one actuator that mechanically positions the articulated supporting arm.

4. The positioning system of claim 3, wherein the actuator is remotely located with respect to the support arm segment it is configured to position.

5. The positioning system of claim 4, wherein a flexible drive cable transmits a positioning force generated by the remotely located actuator to the support arm segment.

6. The positioning system of claim 5, wherein the positioning of the remotely located actuator reduces heat, vibration, and weight along the articulated supporting arm.

7. The positioning system of claim 4, wherein a flexible drive cable transmits a positioning torque generated by the remotely located actuator to the support arm segment.

8. The positioning system of claim 7, wherein the positioning of the remotely located actuator reduces heat, vibration, and weight along the articulated measuring arm.

9. An accurate positioning system comprising:

an articulated supporting arm comprising a plurality of jointedly interconnected support arm segments moveable about a plurality of axes;

a plurality of compliant members positioned about said supporting arm;

an articulated measuring arm comprising a plurality of jointedly interconnected measuring arm segments capable of a plurality of degrees of freedom of movement and supported by said compliant members wherein said compliant members provide a yielding characteristic that resists a degree of compressibility of each compliant member when a force is applied to one of the articulated supporting arm and the articulated measuring arm;

a controller configured to direct positioning of the articulated supporting arm;

a datastore containing information that is accessible by the controller and used to resolve the alignment of the articulated supporting arm with respect to the articulated measuring arm; and

at least one actuator that mechanically positions the articulated supporting arm as directed by the controller.

10. An accurate positioning system comprising:

an articulated supporting arm comprising a plurality of jointedly interconnected support arm segments moveable about a plurality of axes;

a plurality of compliant members positioned about said supporting arm;

an articulated measuring arm comprising a plurality of jointedly interconnected measuring arm segments capable of a plurality of degrees of freedom of movement and supported by said compliant members wherein said compliant members provide a yielding characteristic that resists a degree of compressibility of each compliant member when a force is applied to one of the articulated supporting arm and the articulated measuring arm;

a controller configured to direct positioning of the articulated supporting arm;

a datastore containing information that is accessible by the controller and used to resolve the alignment of the articulated supporting arm with respect to the articulated measuring arm; and

at least one alignment detector configured to generate alignment information characterizing the alignment of the articulated supporting arm and the alignment of the articulated measuring arm and further configured to provide the alignment information to the controller.

11. The positioning system of claim 10, wherein the at least one alignment detector comprises an encoder configured to detect the alignment of the articulated supporting arm and the articulated measuring arm.

12. The positioning system of claim 10, wherein the at least one alignment detector comprises a first encoder configured to ascertain the position of the articulated supporting arm and a second encoder is configured to ascertain the position of the articulated measuring arm.

13. The positioning system of claim 12, wherein the controller receives information from the first and second encoders and determines the alignment of the articulated supporting arm with respect to the articulated measuring arm on the basis of the encoder information evaluated against pre-determined encoder information contained in the datastore.