Laser obstacle detection method and sensor
US5970433A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1997 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Feb 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05D1/0272
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor detects the presence or the absence of an obstacle by radiating a laser beam to the outside of a casing through a light projecting mirror and by letting the reflected light from an obstacle enter a light receiving element through a light receiving mirror. A light projecting window with a light projecting mirror positioned and a light receiving window with a light receiving mirror are positioned in the casing with a space therebetween to prevent reflected light from directly entering the light projecting window. The mirrors are attached to a rotation shaft of a motor, or rotation shafts of motors, synchronously rotatable provided between both mirrors. The optical axis of light radiated to the outside of the casing is set to face in a higher direction than horizontal to radiate in a cone-shaped form. By comparing a received light signal from a light receiving circuit to an output signal from a circuit for a previously set threshold, which has a correlation between detected distance and light intensity, a light receiving trigger is output. The distance is calculated when a signal is greater than the threshold. The presence or the absence of an obstacle is determined by the de…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.