Integrated enclosure and controller for video surveillance camera
US6913403B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2004 |
| Grant date | Jul 5, 2005 |
| Priority date | — |
| Expiry date | Dec 15, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N23/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A controller for a video surveillance camera enclosure including a method and apparatus for controlling a stepper motor by decoding a command for a specific camera action, setting the state of a state machine, and instructing a position control process and a speed control process based upon the state of the state machine. A drive signal is send from said position control process to a motor current process and a phase control process to generate the current and phase signals to control the stepper motor. The stepper motor drive current is preferably a non-linear current. The speed control signal includes ramp up and ramp down speed control for gradually increasing motor speed and gradually decreasing motor speed, respectively. Another aspect of the invention detects a plurality of pan and/or tilt positions to reset the pan and/or tilt motor step count to a known count associated with a known location without the need to pan and/or tilt past a preselected home position. Another aspect controls a dome enclosure heater to operate over two different thermostat ranges to provide for manual de-fogging of the dome bubble.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.