US5321353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System and method for precisely positioning a robotic tool
Assignee: Storage Technology Corp
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Filing: 1992-05-13
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Granted: 1994-06-14
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Expires: 2012-05-13
Abstract
Abstract A system and method for precisely positioning a robotic tool relative to a worksite, wherein the worksite includes a positioning target located at a fixed position relative thereto is disclosed. A camera coupled to the robotic tool detects the target and generates a position signal representing a current position of the robotic tool relative to the worksite. A system controller receives the position signal and computes a parallax-corrected position based on the distance to the worksite. In addition, the system controller produces a correction signal representing the difference between the parallax-corrected position and the current position. A mechanical arm precisely positions the robotic tool and the worksite relative to each other.
Inventors
- 👤 Duncan Furness
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 02:22
CPC Classifications
B; B25; B25J; B25J9/00; B25J9/16; B25J9/1694; B25J9/1697
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
276 words
An apparatus for precisely positioning a robotic tool relative to a worksite, wherein the worksite has a target located at a fixed position relative thereto, the apparatus comprising: (a) a camera, mounted to the robotic tool at an angle, operable to: (1) focus an image of the target onto a focal plane so that when the robotic tool is at a nominal distance from the worksite, said image appears at a specified position on the focal plane, and to (2) generate a position signal indicating a current position of the robotic tool relative to the worksite, as indicated by an actual position on said focal plane where said image of the target appears; (b) a system controller, in communication with said camera, operable to (1) determine a parallax corrected position of said image of the target on said focal plane, wherein said parallax corrected position is separated from said specified position for tool distances other than said nominal distance, said parallax corrected position corresponds to parallax free positioning of the robotic tool relative to the worksite, and said parallax corrected position is based on (i) said nominal distance between the robotic tool and the worksite and any variation in distance from said nominal distance, (ii) said angle, and (iii) a focal length of said camera, and (2) generate a position correction signal representing a difference between said current position of the robotic tool relative to the worksite and said desired position of the robotic tool relative to the worksite; and (c) a positioning mechanism, in communication with said system controller, to reposition the robotic tool relative to the worksite in response to said position correction signal.
Claim 2
Independent Claim
276 words
An apparatus for precisely positioning a robotic tool relative to a worksite, wherein the worksite has a target located at a fixed position relative thereto, the apparatus comprising: (a) a camera, mounted to the robotic tool at an angle, operable to: (1) focus an image of the target onto a focal plane so that when the robotic tool is at a nominal distance from the worksite, said image appears at a specified position on the focal plane, and to (2) generate a position signal indicating a current position of the robotic tool relative to the worksite, as indicated by an actual position on said focal plane where said image of the target appears; (b) a system controller, in communication with said camera, operable to (1) determine a parallax corrected position of said image of the target on said focal plane, wherein said parallax corrected position is separated from said specified position for tool distances other than said nominal distance, said parallax corrected position corresponds to parallax free positioning of the robotic tool relative to the worksite, and said parallax corrected position is based on (i) said nominal distance between the robotic tool and the worksite and any variation in distance from said nominal distance, (ii) said angle, and (iii) a focal length of said camera, and (2) generate a position correction signal representing a difference between said current position of the robotic tool relative to the worksite and said desired position of the robotic tool relative to the worksite; and (c) a positioning mechanism, in communication with said system controller, to reposition the robotic tool relative to the worksite in response to said position correction signal.
Claim 3
Dependent Claim
32 words
The apparatus of claim 1, wherein said positioning mechanism is coupled to the robotic tool and is configured to reposition the robotic tool relative to the worksite by moving the robotic tool.
Claim 4
Dependent Claim
30 words
The apparatus of claim 1, wherein said positioning mechanism is coupled to the worksite and is configured to reposition the robotic tool relative to the worksite by moving the worksite.
Claim 5
Dependent Claim
20 words
The apparatus of claim 1, wherein said positioning mechanism comprises a plurality of position arms, position encoders and electric motors.
Claim 6
Dependent Claim
19 words
The apparatus of claim 1, further comprising means for measuring said distance between the worksite and the robotic tool.
Claim 7
Dependent Claim
19 words
The apparatus of claim 1, further comprising memory means for storing said distances measured by said means for measuring.
Claim 8
Dependent Claim
25 words
The apparatus of claim 1, wherein said positioning mechanism further comprises means for coarsely positioning the robotic tool and the worksite relative to each other.
Claim 9
Independent Claim
281 words
A method for precisely positioning a robotic tool relative to a worksite, wherein the robotic tool has a camera mounted at an angle thereto, and wherein the worksite has a target located at a fixed position relative thereto, the method comprising the steps of: (1) focusing an image of the target onto a focal plane of the camera so that when the robotic tool is at a nominal distance from the worksite, said image appears at a specified position on the focal plane; (2) generating an image position signal representing an actual position on said focal plane where said image of the target appears, said image position signal representing a perceived position of the robotic tool relative to the worksite; (3) computing a parallax-corrected position of said image of the target on said focal plane, said parallax-corrected position representing the focal plane position on which said image must appear for the tool to be in a precise position relative to the worksite, wherein said parallax-corrected position is determined based on the angle of the camera, a focal length of the camera, said nominal distance between the tool and the worksite, and any variation from said nominal distance; (4) computing a difference between said actual position of said image and said parallax-corrected position of said image, said difference representing a difference between said perceived position and said actual position of the robotic tool relative to the worksite; (5) generating a position correction signal based on a difference between said actual position of said image and said parallax-corrected position of said image; and (6) repositioning the robotic tool to said precise position relative to the worksite in response to said position correction signal.
Claim 10
Independent Claim
281 words
A method for precisely positioning a robotic tool relative to a worksite, wherein the robotic tool has a camera mounted at an angle thereto, and wherein the worksite has a target located at a fixed position relative thereto, the method comprising the steps of: (1) focusing an image of the target onto a focal plane of the camera so that when the robotic tool is at a nominal distance from the worksite, said image appears at a specified position on the focal plane; (2) generating an image position signal representing an actual position on said focal plane where said image of the target appears, said image position signal representing a perceived position of the robotic tool relative to the worksite; (3) computing a parallax-corrected position of said image of the target on said focal plane, said parallax-corrected position representing the focal plane position on which said image must appear for the tool to be in a precise position relative to the worksite, wherein said parallax-corrected position is determined based on the angle of the camera, a focal length of the camera, said nominal distance between the tool and the worksite, and any variation from said nominal distance; (4) computing a difference between said actual position of said image and said parallax-corrected position of said image, said difference representing a difference between said perceived position and said actual position of the robotic tool relative to the worksite; (5) generating a position correction signal based on a difference between said actual position of said image and said parallax-corrected position of said image; and (6) repositioning the robotic tool to said precise position relative to the worksite in response to said position correction signal.
Claim 11
Dependent Claim
19 words
The method of claim 8, further comprising a step: measuring the distance from the robotic tool to the worksite.
Claim 12
Dependent Claim
18 words
The method of claim 8, wherein said parallax corrected position is stored in a memory for later use.
Claim 13
Dependent Claim
39 words
The method of claim 8, wherein said step (3) of determining said parallax corrected position is performed in advance for each worksite and each of said parallax corrected positions determined in said step (3) is stored for later use.
Claim 14
Dependent Claim
47 words
The method of claim 8, further comprising the step of measuring an actual distance from said robotic tool to said worksite in advance for each of a plurality of worksites and storing said actual distance, wherein said actual distance includes said nominal distance and said variation therefrom.
Claim 15
Dependent Claim
21 words
The method of claim 12, further comprising the step of determining said variation from said nominal distance and storing said variation.
Claim 16
Dependent Claim
54 words
The method of claim 8, further comprising the steps of: measuring an actual distance from said robotic tool to said worksite in advance for each of a plurality of worksites; and determining a difference between said actual distance measured and said nominal distance, and storing said difference as said variation from said nominal distance.
Claim 17
Dependent Claim
22 words
The method of claim 8 further comprising a step before step (1) of coarsely positioning said robotic tool relative to the worksite.
Claim 18
Dependent Claim
71 words
The method of claim 8, wherein said parallax corrected position is determined as an offset from a center of the focal plane, wherein said offset can be determined in each dimension by the equation: ##EQU5## wherein, ψ cc is said offset, f is said focal length, d nom is said nominal distance, Δd is said variation from said nominal distance, and γ is said angle of said camera to said tool.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-06-13 | 1997-12-13 | 1998-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-06-13 | 2001-12-13 | 2002-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-06-13 | 2005-12-13 | 2006-06-14 | $7700.00 | Window Closed / Lapsed |