LINEAR DRIVEN X-Z ROBOT

• US 20090088912A1
• Filed: 09/28/2007
• Published: 04/02/2009
• Est. Priority Date: 09/28/2007
• Status: Abandoned Application

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.), Anorad Corporation (Rockwell Automation, Inc.)
• Original Assignee: Anorad Corporation (Rockwell Automation, Inc.)
• Inventors: Rajaraman, Devarajan
• Application Number:
  US11/864,796
• Publication Number:
  US 20090088912A1
• Time in Patent Office: Days
• US Class Current: 701/19
• CPC Class Codes: B25J 9/106 with articulated links
• CPC Class Codes: G05B 2219/40252 Robot on track, rail moves only back and forth
• CPC Class Codes: G05B 2219/41337 Linear drive motor, voice coil
• CPC Class Codes: Y10T 74/20305 Robotic arm

Abstract

Systems and methods of positioning a tool using a linear motor with a plurality of stages on a single path. A single rail and a plurality of trucks containing stages can comprise a linear motor. The trucks can connect to a tool through a linkage such as a four bar linkage or a scissor jack. The global position of the stages can be manipulated to effectuate motion along the path; the relative position, velocity, and acceleration of the trucks can be manipulated to effectuate motion in another direction such as a direction perpendicular to the path.

Claims

1. A linear motor drive, linear positioning system, comprising:

a rail that defines the path of motion of the positioning system;

a first truck and a second truck that together with the rail define a linear motor;

a plurality of arms that extend between the first and second trucks to a tool, relative motion of the first and second trucks causes motion of the tool in a direction substantially perpendicular to the path of motion of the positioning system.

2. The system of claim 1, further comprising a control component that controls the relative motion of the trucks.

3. The system of claim 2, the control component prevents the first and second trucks from exceeding at least one of a minimum or a maximum relative distance along the path.

4. The system of claim 2, the control component prevents the trucks from undesirable contact with and end of the rail.

5. The system of claim 1, coordinated motion of the first and second trucks causes movement in a direction along the path of motion of the positioning system.

6. The system of claim 1, the arms comprise substantially rigid connectors that are rotatably connected to the trucks at one end, and to the tool at another end.

7. The system of claim 1, the arms comprise a plurality of substantially rigid members that comprise a scissor-jack mechanism.

8. The system of claim 1, the relative motion of the first and second trucks, the arms, and the tool comprise a four bar linkage.

9. The system of claim 1, the arms are rotatable connected to the first and second trucks, the angular position of the arms is selectively fixed with respect to the trucks.

10. The system of claim 1, further comprising a mechanical limiter that limits motion of the first and second trucks from exceeding at least one of a minimum or maximum relative distance.

11. The system of claim 10, further comprising a control component that prevents the trucks from exceeding at least one of maximum or minimum relative distance.

12. The system of claim 11, the control component senses at least one of position, velocity, or acceleration of at least one of the first or second trucks to prevent exceeding at least one of maximum or minimum relative distance.

13. The system of claim 1, the rail comprises a magnetic path and the trucks comprise the stages to form an iron core, attraction force linear motor.

14. The system of claim 1, the rail includes the windings and the trucks include U-shaped magnetic channels to form a zero attraction force, balanced type linear motor.

15. A method of positioning a tool using a linear motor driven, linear positioning system with a plurality of stages on a single path, comprising:

determining a target and a location of the target, the location of the target comprising a distance in an X-direction along the path and a Z-direction;

determining a relative Z-direction height difference (Ah) between a current position and the target;

determining a center-to-center distance (AC) between the current position and the target;

directing movement of a front stage the distance Δ

C+(∂

/2), and a rear stage a distance Δ

C+(∂

/2), where ∂

is an X-direction difference between the stages that produces the height difference Δ

h.

16. The method of claim 15, the X-direction and the Z-direction are substantially perpendicular.

17. The method of claim 15, further comprising directing the front and rear stages to move to alter the Z-direction position to acquire the target.

18. The method of claim 15, further comprising directing relative movement of the stages to account for obstacles in the path.

19. The method of claim 15, further comprising manipulating an angular position of an arm that connects at least one of the front and rear stage to a tool.

20. A system for positioning a tool relative to an object, comprising:

means for positioning a first stage along a linear path;

means for positioning a second stage along a linear path;

means for connecting the first and second stages to a tool, global movement of the first and second stages in a first direction moves the tool in the first direction, and relative movement of the first and second stages moves the tool in a second direction; and

means for acting upon the object.