Application Of Auto-tracking System To Extend The Range Of Displacement Measurement With Hore Sensor

According to More Effect,when the Hore component is placed in a gradient field,at the same time the direction of the current is perpendicular to the direction of the voltage,then between the two parallel side face come out the Hore voltage. When Hore component is set in this kind of uni-gradient magnetic field and the electric current is unchanged,the voltage output of Hore component will be proportional to the position of the Hore component in the magnetic field. So we can use the Hore component to measure the movement of Hore component against magnetic field.Compared to other means,using Hore component to measure the displacement of object has some advantages including smaller transient response,better dynamic properties,non-contact and higher accuracy of measurement. However,the magnetic field produced by common magnet can keep the gradient unchanged only in a small area. So,if we use common magnet and Hore component to measure the movement of the object,we can only measure in a small area. If we want to compose in a larger area a uni-gradient magnetic field,the device will be too complicated and unfit for move. It will restrict the application of Hore component in displacement measuring. In order to change this situation,in this dissertation,a kind of auto-tracking measuring system is introduced. The Hore component is set on the tracking mechanical system to detect the magnetic field's movement. Under this situation,the Hore component will always keep up with the target's movement and keep in the magnet's unitary gradient magnetic field.On this subject,Chen Wenxiang's Using feedback servo mechanism to scale-up the measurement range on the shift by Hore sensor and Chen Dongjun's Study of a kind of Hore shift sensor with feedback servo mechanism have achieve the rudimental results. It shows that using self-tracking or servo system to scale-up the measurement range of the Hore sensor is reasonable. However,there is still some problems in their study:1. Because their application of alternating current channel,their system can't be applied under static situation. And when the system is applied under dynamic situation,there will be a great phase discrepancy;2. Temperature influence the Hore sensors greatly. In their study,they didn't give out the ways to compensate the temperature error;3. Their study on the structure of the servo mechanism is still too simple;In order to resolve the problems in their study,I have done these jobs:1. Applying a direct current channel to the system to make it possible that the system be used under both static and dynamic situation. And the phrase discrepancy will be limited between 0 - 15 under dynamic situation;2. Applying a temperature compensating system to the whole system. The temperature error be limited to 2%;3. Using "Voice-coil motor" to define the servo mechanism,and give out a deeper study of the structure of the servo mechanism.4. By the way,a displaying system and a communicating system is added.This dissertation is divided into four chapters altogether:chapter one is the introduction,introducing the Hore component and its important characteristic and putting forward the basic task;Chapter two introduce the principle of the auto-tracking system and respective parts of the auto-tracking system;Chapter three introduce the applications of auto-tracking system under static condition and dynamic condition and give out the experiment results;Chapter four introduced the displaying system,communicating system and the applicability of the auto-tracking system to other sensors.