Self calibrating lighting control system
US5381074A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1993 |
| Grant date | Jan 10, 1995 |
| Priority date | — |
| Expiry date | Jun 1, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60K2360/349
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A lighting control system with self calibration for employing the entire physical travelling range of a dimmer switch. A lookup table and linear interpolation are used in conjunction with the voltage output of the dimmer switch in order to identify the appropriate duty cycle of a Pulse Width Modulated signal which drives the lamps in the system. Two of the values in the lookup table are default minimum and maximum values of voltage which can be expected from a worst case switch device. The system dynamically determines and stores any new maximum or minimum voltage which is received from the dimmer switch. These dynamically determined minimum and maximum values are used to replace the default values in the lookup table thus calibrating the lookup table. The calibrated lookup will take into account the operating parameters of the actual switch in the vehicle and will therefore always produce a corresponding change in illumination intensity over the entire physical range of the dimmer switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.