METHOD AND SYSTEM FOR LOW SPEED CONTROL OF A VIDEO SURVEILLANCE SYSTEM MOTOR

摘要

The present invention provides a method and system that improve the low-s peed control stability of a video camera assembly, including a video camera, a tilt motor operable to tilt the video camera and a pan motor operable to pan the video camera. A first encoder is coupled to one of the tilt motor an d pan motor. The first encoder outputs a plurality of signals having corresp onding signal edges, based on a rotation speed of the one of the tilt motor and pan motor. A first controller is in electrical communication with the fi rst encoder. The first controller determines a speed of the one of the tilt motor and pan motor at least in part by correlating a time period between de tection of the first edge and detection of the second edge to the speed of t he at least one tilt motor and pan motor.