Lightweight pointing mechanism and its pointing error analysis based on ultrasonic motor

In the lunar exploration project, in order to achieve multi-target spectrum detection based on space applications, designing a lightweight and highly reliable two-dimensional pointing mechanism is needed. Currently, the ultrasonic motor as a driving source and the precise potentiometer as a position sensor, are gradually applied in precise instruments and positioning technologies due to their excellent performance. Based on this, a two-dimensional pointing mechanism consisting of ultrasonic motor, precise potentiometer and scanning mirror was designed. Besides, in order to validate feasibility of the two-dimensional pointing mechanism in space applications, one-dimensional pointing mechanism model was designed and assembled as the engineering prototype, and functional test was conducted based on the closed-loop control circuit and pointing control mechanism. In order to meet the demand of accuracy test, laboratory test platform was built, several pointing experiments were carried out to measure and solutions to improve accuracy were put forward through error analysis of the test results.