Vision system with environmental control

• US 4,652,133 A
• Filed: 07/17/1985
• Issued: 03/24/1987
• Est. Priority Date: 07/17/1985
• Status: Expired due to Fees

• Current Assignee: AEG Westinghouse Industrial Automation Corporation
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Sciulli, Frank J., Clements, Jack W., Taft, Jeffrey D., Antoszewski, Richard S.
• Primary Examiner(s): Evans, F. L.
• Application Number:
  US06/756,002
• Time in Patent Office: 615 Days
• Field of Search: 356/375, 356/376, 219/124.34, 358/101
• US Class Current: 356/606
• CPC Class Codes: B25J 19/0079 using an internal pressure system
• CPC Class Codes: B25J 19/021 Optical sensing devices
• CPC Class Codes: B25J 9/1684 Tracking a line or surface by means of sensors
• CPC Class Codes: G01S 17/42 Simultaneous measurement of distance and other co-ordinates indirect measurement G01S17/46

Abstract

A vision sensor for tracking includes a light stripe vision sensor for use in harsh environments. This light stripe generator is light source independent and produces a light stripe without the use of lenses. Additionally, the enclosure in which the light stripe generating and detecting means are mounted includes an environmental control system which provides pressurized, conditioned air into the apparatus enclosure in order to control the affects of dust, humidity and temperature variations countered in many working environments. This vision system is particularly well suited for use in welding applications and can be easily used in combination with an industrial manipulator to provide automated vision sensor capabilities.

Claims

1. A vision sensor system comprising in combination a vision sensor apparatus and an environmental control system for said vision sensor apparatus which apparatus comprises:

a sensor enclosure means including a base member having ports therein;

light detecting means mounted within said enclosure means and capable of selectively focusing onto a predetermined point on a work surface;

means for generating a light beam for propagation along a first predetermined path, mounted within said enclosure means;

first mirror means mounted in said enclosure means for directing said light beam from said first predetermined path to a second predetermined path;

convex mirror means disposed in said enclosure means along the second path for reflecting said light beam, wherein said light beam strikes said convex mirror means at multiple points thereon and is reflected as a stripe directed along a third predetermined path; and

second mirror means mounted in said enclosure means for reflecting said stripe from said third predetermined path to the work surface for detection thereon by said light detector means wherein features of the work surface are evidenced by the geometry of the light stripe projected thereon wherein the light detecting means, light generating means, convex mirror means and first and second mirror means disposed within the enclosure means are mounted on said sensor enclosure means base member and wherein the base member is removably secured to the enclosure means such that the above-identified components mounted on said base member can be removed from said enclosure means while mounted on said base member for test and alignment;

and wherein said environmental control system is in communication with said sensor enclosure means for delivering pressurized conditioned air thereto, said environmental control system comprising;

means for sensing the temperature within said sensor enclosure means;

means for selectively providing a source of filtered dry hot air, filtered dry cold air and/or filtered ambient air; and

valve means in communication with the air providing means and responsive to the sensing means for effecting the delivery of conditioned air under pressure to said sensor enclosure wherein the environment within the housing is maintained within a predetermined temperature range despite temperature variations in the environment and said ports in said base member direct the flow of pressurized conditioned air about the outside of said base member.

2. The system of claim 1 wherein the means for generating a light beam is a laser.

3. The system of claim 1 wherein the first and second mirror means and the convex mirror means are adjustable.

4. The system of claim 1 in combination with a robotic system of the type having an X, Y and Z axes assembly supported in gantry type configuration with an overhead X axis supported by vertical structural members, a Y axis assembly extending from the X axis assembly and a vertical Z axis assembly supported by the Y axis and wherein the vision system is operatively associated with the Z axis.

5. The system of claim 1 wherein the convex mirror means is a cylindrical lens overcoated with aluminum on the curved surface thereof.