Variable beam detection using a dynamic detection threshold
US5567931A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1994 |
| Grant date | Oct 22, 1996 |
| Priority date | — |
| Expiry date | Oct 25, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66B13/26
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for detecting obstructions includes a plurality of emitters for radiating beams of energy, a plurality of detectors for providing detector signals in response to the beams of energy radiated by the plurality of emitters and a controller for determining if the beams of energy are obstructed by analyzing the detector signals and implementing a dynamic detection threshold. The controller generates an average beam strength and current beam strength from which said controller means determines if an obstruction is present by determining if the current beam strength is within a predetermined range of the average beam strength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.