Study On Key Technologies Of A Dual-Butterfly Structure Gyroscope

MEMS gyroscope has been playing an important role in both military and civilian fields and are widely used in consumer electronics,automotive safety and inertial navigation.Based on the research of the Butterfly gyroscope developed in our laboratory,a new coupling mechanism is designed to connect two separate butterfly gyroscopes,and the dual-butterfly structure gyroscope prototype is successfully realized.The structural characteristics,processing technology and measurement and control circuit of the new gyroscope are also studied.The main contents include:1.The domestic and foreign high-performance gyroscope were studied,and the directions of improvement to the given the traditional butterfly gyroscope were given,which are symmetrical structure,multi-sensitive mass and multiple differential.2.The Coriolis force and the working principle of angular vibration gyroscope are analyzed.The structure and working principle of the traditional butterfly gyroscope,tangential-driven butterfly gyroscope,and symmetrical structure-based butterfly gyroscope are introduced respectively.The characteristics of the coupling connection mechanism are analyzed and it is found that the coupling mechanism can increase the frequency of the in-phase mode and reduce the anti-phase mode frequency.Finally,the tangential driving torque and the Coriolis force of the micro-gyroscope are deduced,and the dynamic equation of the new butterfly wing gyroscope is established,so as the expression of the mechanical sensitivity.3.Based on the structural characteristics of the rectangular section of the new gyroscope,the silicon structure processing using the deep reactive ion etching(DRIE)was determined.The DRIE process and its "load effect" and "groove effect" are introduced,and then the processing scheme of the micro-gyroscope is determined around these two problems.The "island" mask design is adopted,and the metal Aluminum is used as an etched mask and base film.Then the glass electrode processing technology,anode bonding process are introduced,and finally gives the prototype of the gyroscope prototype package.4.Several methods of weak capacitance detection are investigated and compared,and the weak capacitance detection based on double high-frequency carriers and its phase relation are analyzed in detail.Then,the closed-loop drive control based on PID controller and phase control technology are introduced,as well as the angular velocity demodulation module.Finally,the method of calculating the actual working parameters of gyroscope by circuit method is introduced.5.The static capacitance test,modal test,scale factor test and zero bias stability test of the gyroscope were carried out.The test results show that the two new butterfly wing gyro prototypes can achieve the desired gyro function,and they two can reach 111.0aF / ° / s and 104.2aF / ° / s in mechanical sensitivity,respectively,and the zero bias stability can reach 24.15°/h and 23.75°/h respectively.