Research On A Single-Pole Magnetic Encoder Used In The Frame Platform Of The Coordinator

Angle sensor is an important feedback component in close-loop servo control system. The angle inspection quality for infrared guidance missile coordinator's frame-platform will affect the aim searching and tracking directly. Because of special working and installation environment, the angle sensor to be designed should meet some requirements, for example, high precision, high resolution, vibration and pollution resistant, miniaturized, etc. Traditional angle sensors include resolver and optical encoder. But their limitations restrict the uses in the fields of spaceflight and war industry. Magnetic encoder has advantages of vibration, corrosion and pollution resistance, and single-pole magnetic encoder is easier to realize high resolution, high precision, miniaturization and low cost. It is a good substitution for traditional sensors and suitable in harsh environments or limited space. So far, there are some researches in this direction. But they cannot meet the requirements of this task because of many deficiencies. Based on the previous research, and aimed to this task, some further research will be held in this paper. The research has some practical and academic value inspect of in the spaceflight or in the industrial control.Aiming at the special demands of the angle sensor in coordinator's frame-platform, a single-pole limited-angle absolute magnetic encoder is researched and developed and high resolution, high precision, miniaturization and high reliability are realized. Fellow are the concrete contents: Firstly, calibration and look-up table subdivision arithmetic, temperature offset correction arithmetic are expounded. Some error resources that can affect the performance of the encoder are discussed in detail and the error boundaries are derived. Secondly, the design and development are held. The design of signal generator and its air gap optimization are described. With analyzing the error resources, the structure and parameters of the encoder are optimized. The limitation for encoder from AD resolution is broken through using oversampling technology. Incremental output interface is developed using DDA arithmetic. Thirdly, the hardware and software of calibration system are researched and developed and its parameters are stated and checked. Limited-angle calibration is exploited according to the special use. The problems of wrong region points judgment is analyzed and solved. The detecting system is developed to detect the performance of the encoder. Finally, calibration and detecting experiments are carried out.Validated by the experiments for this magnetic encoder, it's calibrated well and it satisfies the demands of the coordinator.