Disc Varifocal Mechanism to Improve Efficiency of Scene Matching Navigation System

In order to meet special requests of optical imaging sensor in scene matching navigation system, a disc varifocal mechanism is proposed for the flight vehicles of long flying time and range. Within small space occupied, it can obtain real images with various resolutions. Moreover, using plate traveling-wave Ultrasonic Motor as its driven motor can reduce energy loss, improve control precision and ensure image obtaining being real-time and stable. Disc varifocal mechanism driven by plate traveling-wave Ultrasonic Motor is high-response, and variation in load doesn´t affect its performance parameter. Therefore, applying disc varifocal mechanism in scene matching navigation system, combing software and hardware, can obviously improve the accuracy, real-time and robust of scene matching navigation system. The experiment showed that when the weight of mechanism was 1.5kg, the shortest starting was 0.6ms, and the shortest shutoff was 0.5ms.