Method for laser-based two-dimensional navigation system in a structured environment
US4796198A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1986 |
| Grant date | Jan 3, 1989 |
| Priority date | — |
| Expiry date | Oct 17, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D1/0272
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A low power, narrow laser beam, generated by a laser carried by a mobile vehicle, is rotated about a vertical reference axis as the vehicle navigates within a structured environment. At least three stationary retroreflector elements are located at known positions, preferably at the periphery of the structured environment, with one of the elements having a distinctive retroreflection. The projected rotating beam traverses each retroreflector in succession, and the corresponding retroreflections are received at the vehicle and focussed on a photoelectric cell to generate corresponding electrical signals. The signal caused by the distinctive retroreflection serves as an angle-measurement datum. An angle encoder coupled to the apparatus rotating the projected laser beam provides the angular separation from this datum of the lines connecting the mobile reference axis to successive retroreflectors. This real-time angular data is utilized with the known locations of the retroreflectors to trigonometrically compute using three point resection, the exact real-time location of the mobile reference axis (hence the navigating vehicle) vis-a-vis the structured environment, e.g., in terms of two…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.