Measuring system for testing the position of a vehicle and sensing device therefore

• US 5,745,235 A
• Filed: 03/26/1997
• Issued: 04/28/1998
• Est. Priority Date: 03/26/1996
• Status: Expired due to Fees

• Current Assignee: Naamloze Vennootschap Egemin
• Original Assignee: Egemin Naamloze Vennootschap
• Inventors: De Feyter, Walter Maria Alfons, Vercammen, Jan Maria Ludovicus
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): KIM, ROBERT H
• Application Number:
  US08/824,742
• Time in Patent Office: 398 Days
• Field of Search: 356/372, 356/373, 356/375, 356/385, 356/138, 356/139, 356/140, 356/141
• US Class Current: 356/623
• CPC Class Codes: B66F 9/24 Electrical devices or systems
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 5/163 Determination of attitude using inertial means G01C9/00; control of attitude G05D1/49

Abstract

A measuring system for testing the position of a vehicle (1) includes a number of optical beacons (6 and 7), a sensing device (10) which is mounted on the vehicle (1) and which generates a position signal when sensing light reflected from a beacon (65 or 7), and a computer processing unit (14) for calculating, starting from the information received from the sensing device (10), the deviation of the vehicle relative to the desired position and driving direction of the vehicle. The sensing device (10) includes two cameras which are mounted on the vehicle, namely, a first camera which is directed approximately along the driving direction, and a second camera which is directed along a direction vertically upward or downward relative to the plane including the path of travel of the vehicle. At least one of the beacons (6) is placed in such a way that, during the motion of the vehicle approximately along the desires path, the beacon can be seen by the sensing device (10) along the driving direction of the vehicle. At least another one of the beacons (7) is positioned along the desired path, but is observable in the direction above or below the aforementioned plane of the path, and is situated above or below the sensing device (10), depending whether the second camera is directed upwards or downwards relative to the plane of the path or travel, each camera may include its own light projector.

Claims

1. A measuring system for detecting the actual position and driving direction of a computer guided vehicle relative to a desired position and driving direction for the vehicle along a predetermined desired path of travel for the vehicle, comprising:

a plurality of first optical beacons located and orientated adjacent the path of travel of the vehicle such that they will be observable in a first viewing direction from said vehicle while said vehicle is moving approximately along said desired path of travel;

a plurality of second optical beacons located above or in the plane of travel of the vehicle and along the desired travel path, said second beacons oriented such that they will be observable in a second viewing direction from said vehicle while said vehicle is moving along said desired path;

sensors on board the vehicle for optically detecting said beacons and generating signals indicative of the angular directions of said beacons relative to reference axes that are related to the desired position and direction of travel of the vehicle;

a computer for receiving said signals from said sensors and processing said signals in accordance with a program that calculates the actual position and driving direction of the vehicle relative to a desired position and driving direction of travel of the vehicle;

said sensors comprising a first camera aimed in a first viewing direction approximately along the driving direction of the vehicle and a second camera directed in a second viewing direction extending perpendicular to the plane of the vehicle travel path, said cameras including optical systems adapted to view and image the location of said beacons.

2. The measuring system according to claim 1, including a separate guide system for the vehicle including a second vehicle actual position and driving direction measuring system.

3. The measuring system according to claim 1, wherein said cameras are electronic random access type cameras.

4. The measuring system according to claim 1, wherein said beacons comprise planar reflectors.

5. The measuring system according to claim 1, wherein a light projector is separately associated with each of said cameras and projects light rays to illuminate said beacons and to which the sensor of each camera is uniquely responsive.

6. The measuring system according to claim 1, including a housing for enclosing said cameras, said housing being transparent to the light projected by said light projectors at least along the line of sight of said cameras.

7. The measuring system according to claim 1, wherein said cameras are oriented to view along directions that are approximately perpendicular to each other.