CN101893722A

Movatterモバイル変換

Info

Publication number: CN101893722A
Application number: CN 201010216016
Authority: CN
Inventors: 王小秋; 付敬奇
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2010-06-29
Filing date: 2010-06-29
Publication date: 2010-11-24
Anticipated expiration: 2030-06-29
Also published as: CN101893722B

Abstract

本发明涉及了一种基于巨磁阻传感器的地磁横滚角测量系统及方法。该系统主要由地磁测量模块、俯仰角测量模块、信号调理模块和微处理器组成。其中地磁测量模块由巨磁阻传感器进行X轴、Y轴和Z轴的地磁测量；俯仰角测量模块由双轴加速度传感器进行X轴俯仰角测量；信号调理模块进行巨磁阻传感器模拟信号的放大、偏置调零、模数转换；微处理器对地磁和俯仰信息进行多传感器融合处理后得到地磁横滚角。本方法设计了放大器偏置调零电路，减小巨磁阻传感器的零位输出，提高横滚角测量的精度；采用了双轴加速度传感器，解决单轴加速度传感器在俯仰角测量时出现多值问题，实现俯仰角唯一性以及横滚角的测量。

The invention relates to a geomagnetic roll angle measurement system and method based on a giant magnetoresistance sensor. The system is mainly composed of a geomagnetic measurement module, a pitch angle measurement module, a signal conditioning module and a microprocessor. Among them, the geomagnetic measurement module uses the giant magnetoresistance sensor to measure the geomagnetism of the X-axis, Y-axis and Z-axis; the pitch angle measurement module uses the dual-axis acceleration sensor to measure the X-axis pitch angle; the signal conditioning module performs the amplification of the analog signal of the giant magnetoresistance sensor , offset zeroing, analog-to-digital conversion; the microprocessor performs multi-sensor fusion processing on the geomagnetic and pitch information to obtain the geomagnetic roll angle. In this method, an amplifier bias zeroing circuit is designed to reduce the zero output of the giant magnetoresistive sensor and improve the accuracy of roll angle measurement; a dual-axis acceleration sensor is used to solve the problem of multi-value in the pitch angle measurement of the single-axis acceleration sensor The problem is to realize the uniqueness of the pitch angle and the measurement of the roll angle.

Description

Translated fromChinese

一种基于巨磁阻传感器的地磁横滚角测量系统及方法A system and method for measuring geomagnetic roll angle based on giant magnetoresistive sensor

技术领域technical field

本发明涉及一种含有放大器偏置调零电路的地磁传感器系统及方法，特别涉及一种基于巨磁阻传感器的地磁横滚角测量系统及方法。属于传感器技术领域。The invention relates to a geomagnetic sensor system and method including an amplifier bias zeroing circuit, in particular to a geomagnetic roll angle measurement system and method based on a giant magnetoresistance sensor. It belongs to the field of sensor technology.

背景技术Background technique

伴随着人类活动领域的不断扩大，航空、航天、航海、地层勘探、深海探测等领域中，姿态角测量技术已为大多数工程领域所必需。目前用于姿态角测量的方法主要有：无线电导航、陀螺仪、地磁定位、太阳方位角定位、恒星天文定位。由于无线电信号受到地形的限制，陀螺仪测量的精度低，高精度的陀螺仪技术复杂，造价昂贵，天体定位受天气的局限，基于地磁传感器系统的姿态角测量很好的解决上述缺点。一般而言，要求这些地磁传感器的灵敏度高、分辨率高、体积小、功耗低等特点。With the continuous expansion of the field of human activities, in the fields of aviation, aerospace, navigation, stratum exploration, deep sea exploration and other fields, attitude angle measurement technology has become necessary for most engineering fields. At present, the methods used for attitude angle measurement mainly include: radio navigation, gyroscope, geomagnetic positioning, solar azimuth positioning, and stellar astronomical positioning. Due to the limitation of radio signals by terrain, the accuracy of gyroscope measurement is low, the technology of high-precision gyroscope is complex and expensive, and the positioning of celestial bodies is limited by the weather. The attitude angle measurement based on the geomagnetic sensor system can solve the above shortcomings very well. Generally speaking, these geomagnetic sensors are required to have high sensitivity, high resolution, small size, and low power consumption.

常见的地磁传感器主要有以下：Common geomagnetic sensors mainly include the following:

1、永磁体罗盘，这种地磁场测量装置的缺点是永磁体磁矩有限而分辨率不高，难以实现小型化，结构复杂，承载能力差。1. Permanent magnet compass, the disadvantage of this kind of geomagnetic field measuring device is that the permanent magnet has limited magnetic moment and low resolution, it is difficult to realize miniaturization, the structure is complex, and the bearing capacity is poor.

2、磁通门罗盘，如专利200610101789.5 CN1971309描述了“地磁传感器及其方位角计算方法”。这类磁通门地磁传感器缺点结构比较大、动态响应慢、解算比较复杂。2. Fluxgate compass, as described in patent 200610101789.5 CN1971309 "Geomagnetic Sensor and Its Azimuth Calculation Method". The disadvantages of this type of fluxgate geomagnetic sensor are relatively large structure, slow dynamic response, and complicated calculation.

3、磁阻传感器，如专利200580035519.2 CN101044412描述了“使用磁阻传感器测量磁场的方法和设备”。它利用的是镍铁合金的电阻只对某一个方向的磁场敏感的原理。由于电阻的体积可以做的很小而且没有活动部件，所以利用磁阻元件构成的姿态角测量仪体积小，可靠性好。其缺点是对温度比较敏感，需要设法消除外界温度变化带来的影响；此外，磁电阻变化率低、灵敏度低，因此提高测量精度会受到很大限制。3. Magnetoresistive sensors, such as patent 200580035519.2 CN101044412 describes "method and equipment for measuring magnetic field using magnetoresistive sensors". It uses the principle that the resistance of the nickel-iron alloy is only sensitive to a magnetic field in a certain direction. Since the size of the resistor can be made very small and there are no moving parts, the attitude angle measuring instrument formed by the magnetoresistive element is small in size and good in reliability. Its disadvantage is that it is sensitive to temperature, and it is necessary to eliminate the influence of external temperature changes; in addition, the change rate of magnetoresistance is low and the sensitivity is low, so the improvement of measurement accuracy will be greatly limited.

因此，如果没有一个精确的地磁场测量传感器，加上带有误差的俯仰角，则不能很好的补偿横滚角，使得横滚角在计算中就有误差。针对上述体积大，灵敏度低等问题，本发明提供了一种基于巨磁阻传感器的地磁横滚角测量系统及方法，体积小，成本低，精度高，具有很好的使用价值。Therefore, if there is no accurate geomagnetic field measurement sensor, plus the pitch angle with errors, the roll angle cannot be well compensated, so that there will be errors in the calculation of the roll angle. Aiming at the above-mentioned problems of large volume and low sensitivity, the present invention provides a geomagnetic roll angle measurement system and method based on a giant magnetoresistive sensor, which is small in size, low in cost, high in precision, and has good use value.

发明内容Contents of the invention

本发明的目的在于针对已有技术的缺陷，提供一种基于巨磁阻传感器的地磁横滚角测量系统及方法，使得利用巨磁阻传感器测量地磁场更精确和更可靠，实现俯仰角唯一性，并利用俯仰角及地磁场分量解算横滚角。The object of the present invention is to address the defects of the prior art, to provide a system and method for measuring the geomagnetic roll angle based on the giant magnetoresistance sensor, so that the measurement of the geomagnetic field by the giant magnetoresistance sensor is more accurate and reliable, and the uniqueness of the pitch angle is realized. , and use the pitch angle and geomagnetic field components to solve the roll angle.

为达到上述本发明的目的，本发明的构思是：For achieving above-mentioned purpose of the present invention, design of the present invention is:

巨磁阻传感器测量地磁场时，由于巨磁阻传感器电桥偏置的原因，即外磁场为零的情况下，传感器输出不为零，进入A/D转换器内的信号范围被缩小，降低了模数转换器的采样分辨率，从而也降低了地磁场和横滚角测量的精确度。When the giant magnetoresistance sensor measures the geomagnetic field, due to the bias of the bridge of the giant magnetoresistance sensor, that is, when the external magnetic field is zero, the sensor output is not zero, and the signal range entering the A/D converter is reduced, reducing The sampling resolution of the analog-to-digital converter is reduced, which also reduces the accuracy of the measurement of the geomagnetic field and roll angle.

加速度传感器进行俯仰角测量时，由于加速度传感器的输出与被测俯仰角之间为Sinθ的关系，显然，单轴加速度传感器测量俯仰角时会出现多值问题，因此解算出来的横滚角不唯一。When the acceleration sensor measures the pitch angle, since the relationship between the output of the acceleration sensor and the measured pitch angle is Sinθ, obviously, there will be a multi-value problem when the single-axis acceleration sensor measures the pitch angle, so the calculated roll angle is not accurate. only.

根据上述发明构思，本发明采用下述技术方案：According to above-mentioned inventive concept, the present invention adopts following technical scheme:

一种基于巨磁阻传感器的地磁横滚角测量系统由地磁测量模块，俯仰角测量模块，信号调理模块，微处理器组成，其特征在于所述地磁测量模块包括两两正交的X轴、Y轴和Z轴巨磁阻传感器；所述俯仰角测量模块包括互相垂直的X轴和Z轴双轴加速度传感器；所述信号调理模块包括经过一个放大器偏置调零电路，一个仪表放大器，连接一个A/D转换器；所述地磁测量模块经信号调理模块连接所述微处理器，所述俯仰角测量模块连接所述微处理器。A kind of geomagnetic roll angle measurement system based on giant magnetoresistive sensor is made up of geomagnetic measurement module, pitch angle measurement module, signal conditioning module, microprocessor, it is characterized in that described geomagnetic measurement module comprises two orthogonal X axes, Y-axis and Z-axis giant magnetoresistive sensors; the pitch angle measurement module includes mutually perpendicular X-axis and Z-axis biaxial acceleration sensors; the signal conditioning module includes a bias zeroing circuit through an amplifier, an instrument amplifier, connected An A/D converter; the geomagnetic measurement module is connected to the microprocessor via a signal conditioning module, and the elevation angle measurement module is connected to the microprocessor.

所述地磁测量模块采用三轴巨磁阻传感器AAH002-02；所述俯仰角测量模块采用双轴加速度传感器ADXL202；所述信号调理模块中仪表放大器采用INA118，A/D转换器为微处理器自带；所述微处理器采用Atmega128L；所述信号调理模块对地磁测量模块的巨磁阻传感器测得模拟信号进行放大、偏置调零和模数转换；所述微处理器对地磁和俯仰信息进行多传感器融合处理后得到地磁横滚角。The geomagnetic measurement module adopts a three-axis giant magnetoresistive sensor AAH002-02; the pitch angle measurement module adopts a biaxial acceleration sensor ADXL202; the instrumentation amplifier in the signal conditioning module adopts INA118, and the A/D converter is a microprocessor automatic belt; the microprocessor adopts Atmega128L; the signal conditioning module amplifies the analog signal measured by the giant magnetoresistive sensor of the geomagnetic measurement module, offsets zero adjustment and analog-to-digital conversion; the microprocessor performs geomagnetic and pitch information The geomagnetic roll angle is obtained after multi-sensor fusion processing.

所述信号调理模块是将巨磁阻传感器模拟信号经放大器偏置调零电路后由仪表放大器放大，再通过A/D转换器转换为数字信号，最后送入微处理器；所述放大器偏置调零电路是：在所述仪表放大器一个输入端接一个数字电位器R_g，通过控制数字电位器R_g，实现电桥供电电压的调整，达到减小巨磁阻传感器零位输出的目的，提高了模数转换器的采样分辨率，从而提高了地磁场测量的精度。The signal conditioning module is to amplify the analog signal of the giant magnetoresistive sensor through the amplifier bias zeroing circuit, and then convert it into a digital signal through the A/D converter, and finally send it to the microprocessor; The zero circuit is: a digital potentiometer R_g is connected to one input terminal of the instrumentation amplifier, and by controlling the digital potentiometer R_g , the adjustment of the power supply voltage of the bridge is realized to reduce the zero output of the giant magnetoresistive sensor and improve The sampling resolution of the analog-to-digital converter is improved, thereby improving the accuracy of the geomagnetic field measurement.

一种基于巨磁阻传感器的地磁横滚角测量方法，采用上述系统进行测量，其特征在于具体操作步骤如下：A method for measuring geomagnetic roll angle based on a giant magnetoresistive sensor, using the above-mentioned system to measure, is characterized in that the specific steps are as follows:

(1)测量基于巨磁阻传感器的地磁横滚角参数；(1) Measure the geomagnetic roll angle parameter based on the giant magnetoresistive sensor;

(2)采集各轴巨磁阻传感器的测量值，根据测量值计算X轴、Y轴和Z轴上磁场分量H″′_X、H″′_Y、H″′_Z；(2) Collect the measured values of the giant magnetoresistive sensors of each axis, and calculate the magnetic field components H″’_X , H″’_Y , H″’_Z on the X-axis, Y-axis and Z-axis according to the measured values;

(3)采集双轴加速度传感器的输出值，利用该输出值计算俯仰角，实现了俯仰角θ唯一性：(3) Collect the output value of the biaxial acceleration sensor, use the output value to calculate the pitch angle, and realize the uniqueness of the pitch angle θ:

(4)利用X轴、Y轴和Z轴地磁场分量H″′_X、H″′_Y和H″′_Z及俯仰角θ，通过式

进行方位角为零的横滚角

计算；(4) Using the X-axis, Y-axis and Z-axis geomagnetic field components H″′_X , H″′_Y and H″′_Z and the pitch angle θ, through the formula

roll angle with zero azimuth

calculate;

(5)输出横滚角

(5) Output roll angle

上述步骤(2)中，AAH002-02传感器利用的是磁场的变化引起阻值的变化，电阻的变化引起惠斯通电桥输出的变化；利用下式ΔV_out＝KSHV_b分别计算X轴、Y轴和Z轴上磁场分量H″′_X、H″′_Y、H″′_Z。式中ΔV_out为AAH002-02输出量，K为INA118放大倍数，S为AAH002-02灵敏度，V_b为激励电压。In the above step (2), the AAH002-02 sensor uses the change of the magnetic field to cause the change of the resistance value, and the change of the resistance causes the change of the output of the Wheatstone bridge; use the following formula ΔV_out = KSHV_b to calculate the X-axis and Y-axis respectively And the magnetic field components on the Z axis H″′_X , H″′_Y , H″′_Z . In the formula, ΔV_out is the output of AAH002-02, K is the magnification of INA118, S is the sensitivity of AAH002-02, and V_b is the excitation voltage .

所述步骤(3)中，实现俯仰角唯一性的具体步骤如下：In described step (3), the concrete steps that realize pitch angle uniqueness are as follows:

根据单轴加速度测量原理，利用等式gSinθ＝Ax计算出来的俯仰角出现多值问题，不能得到唯一的测量值。本发明利用双轴加速度传感器ADXL202，给出了一种判别俯仰角象限的方法：根据X轴加速度传感器测量值Ax和Z轴测量值Az的正负性判断俯仰角的象限。将X轴加速度传感器测量值Ax代入等式θ＝arcSin(Ax/g)计算俯仰角，当Ax大于0，Az大于0时，则所述θ为俯仰角；当Ax大于0，Az小于0时，则180°-θ为俯仰角；当Ax小于0，Az小于0时，则180°+|θ|为俯仰角；当Ax小于0，Az大于0时；则360°-|θ|为俯仰角。According to the principle of uniaxial acceleration measurement, the pitch angle calculated by the equation gSinθ=Ax has multi-value problems, and a unique measurement value cannot be obtained. The present invention utilizes the dual-axis acceleration sensor ADXL202 to provide a method for judging the quadrant of the pitch angle: judge the quadrant of the pitch angle according to the positive or negative of the X-axis acceleration sensor measurement value Ax and the Z-axis measurement value Az. Substitute the measured value Ax of the X-axis acceleration sensor into the equation θ=arcSin(Ax/g) to calculate the pitch angle. When Ax is greater than 0 and Az is greater than 0, then the θ is the pitch angle; when Ax is greater than 0 and Az is less than 0 , then 180°-θ is the pitch angle; when Ax is less than 0 and Az is less than 0, then 180°+|θ| is the pitch angle; when Ax is less than 0 and Az is greater than 0; then 360°-|θ| is the pitch horn.

本发明与现有的技术相比较，具有如下显而易见的突出实质性特点和显著的优点：Compared with the prior art, the present invention has the following obvious outstanding substantive features and remarkable advantages:

(1)巨磁阻变化率高，灵敏度高，采用巨磁阻传感器测量地磁场精确度高；(1) The change rate of giant magnetoresistance is high, the sensitivity is high, and the accuracy of measuring the earth's magnetic field by using giant magnetoresistance sensor is high;

(2)采用放大器偏置调零电路，减少了巨磁阻传感器零位输出，提高了地磁场测量精度；(2) The amplifier bias zeroing circuit is used to reduce the zero output of the giant magnetoresistive sensor and improve the measurement accuracy of the geomagnetic field;

(3)适合对低磁场的测量；(3) Suitable for the measurement of low magnetic field;

(4)硬件设计电路简单，测量装置体积小；(4) The hardware design circuit is simple, and the measuring device is small in size;

(5)采用象限判别法可以得到唯一的俯仰角，提高横滚角的测量精度；(5) The only pitch angle can be obtained by using the quadrant discrimination method, which improves the measurement accuracy of the roll angle;

(6)成本低，功耗低。(6) Low cost and low power consumption.

附图说明Description of drawings

图1是基于巨磁阻传感器的地磁横滚角测量系统的构造框图。Figure 1 is a structural block diagram of a geomagnetic roll angle measurement system based on a giant magnetoresistive sensor.

图2是图1的地磁横滚角测量系统中设计的信号调理模块电路结构图。Fig. 2 is a circuit structure diagram of a signal conditioning module designed in the geomagnetic roll angle measuring system of Fig. 1 .

图3是一种计算横滚角方法的流程图。Fig. 3 is a flowchart of a method for calculating roll angle.

图4是图3横滚角计算方法中测量地磁场的流程图。Fig. 4 is a flow chart of measuring the earth's magnetic field in the calculation method of the roll angle in Fig. 3 .

图5是图3横滚角计算方法中确定俯仰角唯一性的象限判别流程图。Fig. 5 is a flow chart of quadrant discrimination for determining the uniqueness of the pitch angle in the calculation method of the roll angle in Fig. 3 .

具体实施方式Detailed ways

本发明的优选实施例结合附图说明如下：Preferred embodiments of the present invention are described as follows in conjunction with the accompanying drawings:

实施例一：参见图1，本巨磁阻传感器的地磁横滚角测量系统由地磁测量模块1、俯仰角测量模块2、信号调理模块3和微处理器4组成。Embodiment 1: Referring to FIG. 1 , the geomagnetic roll angle measurement system of the giant magnetoresistive sensor is composed of ageomagnetic measurement module 1 , a pitchangle measurement module 2 , asignal conditioning module 3 and amicroprocessor 4 .

所述地磁测量模块1包含互相正交的X轴、Y轴和Z轴的3轴巨磁阻传感器AAH002-02。AAH002-02输出与外部地磁场相对应的电压值，因此，通过各轴传感器的输出值来获得相对应的地磁场分量。Thegeomagnetic measurement module 1 includes a 3-axis giant magnetoresistive sensor AAH002-02 with mutually orthogonal X-axis, Y-axis and Z-axis. AAH002-02 outputs the voltage value corresponding to the external geomagnetic field, therefore, the corresponding geomagnetic field component is obtained through the output value of each axis sensor.

俯仰角测量模块2包含互相垂直的X轴和Z轴的加速度传感器ADXL202。ADXL202输出与地磁传感器系统主体的倾斜相对应的加速度，它们之间有gSinθ＝Ax，gCosθ＝Az的关系，因此，通过双轴加速度传感器可以进行俯仰角测量，实现俯仰角的唯一性。The pitchangle measurement module 2 includes an acceleration sensor ADXL202 with X-axis and Z-axis perpendicular to each other. ADXL202 outputs the acceleration corresponding to the inclination of the main body of the geomagnetic sensor system. There is a relationship between them gSinθ=Ax and gCosθ=Az. Therefore, the pitch angle can be measured through the dual-axis acceleration sensor to achieve the uniqueness of the pitch angle.

信号调理模块3包含仪表放大器INA118、A/D转换器和放大器偏置调零电路。巨磁阻传感器AAH002-02输出信号通过仪表放大器INA118放大后，进入A/D转换器转换成微处理器Atmega128L能处理的数字信号。Signal conditioning module 3 includes instrumentation amplifier INA118, A/D converter and amplifier bias zeroing circuit. The output signal of the giant magnetoresistive sensor AAH002-02 is amplified by the instrument amplifier INA118, and then enters the A/D converter to convert it into a digital signal that can be processed by the microprocessor Atmega128L.

微处理器Atmega128L 4对地磁和俯仰信息进行多传感器融合处理后得到地磁横滚角。Themicroprocessor Atmega128L 4 performs multi-sensor fusion processing on the geomagnetic and pitch information to obtain the geomagnetic roll angle.

实施例二：本实施例与实施例一相同，特殊之处如下：参见图2所述地磁横滚角测量系统中信号调理模块3电路结构图，巨磁阻传感器AAH002-02模拟信号经偏置调零电路和仪表放大器INA118放大，再通过A/D转换器转换为数字信号，最后送入微处理器Atmega128L。放大器偏置调零电路含有一个数字电位器R_g和两个固定电阻R₂。在地磁场与巨磁阻传感器敏感轴平行时，巨磁阻传感器有偏置电压输出，此时，通过调节数字电位器R_g的阻值给仪表放大器加入一个极性相反的电压，以产生一个相反的直流电压强度消除偏置，其电压大小为供电电压的一半减去电桥的偏置电压。Embodiment 2: This embodiment is the same asEmbodiment 1, and the special features are as follows: Refer to the circuit structure diagram ofsignal conditioning module 3 in the geomagnetic roll angle measurement system described in Fig. 2, the analog signal of giant magnetoresistance sensor AAH002-02 is bias The zero-adjustment circuit and the instrumentation amplifier INA118 amplify, and then convert it into a digital signal through the A/D converter, and finally send it to the microprocessor Atmega128L. The amplifier bias zeroing circuit consists of a digital potentiometer R_g and two fixed resistors R₂ . When the geomagnetic field is parallel to the sensitive axis of the giant magnetoresistance sensor, the giant magnetoresistance sensor has a bias voltage output. At this time, by adjusting the resistance value of the digital potentiometer R_g , a voltage with opposite polarity is added to the instrument amplifier to generate a The opposite DC voltage strength cancels the bias, which is half the supply voltage minus the bridge bias voltage.

实施例三：参见图3，图4，图5，本基于巨磁阻传感器的地磁横滚角测量方法，具体步骤如下：Embodiment three: referring to Fig. 3, Fig. 4, Fig. 5, the method for measuring the geomagnetic roll angle based on the giant magnetoresistive sensor, the specific steps are as follows:

(1)如图3流程1，测量基于巨磁阻传感器的地磁横滚角参数。(1) As shown inprocess 1 of Figure 3, measure the parameters of the geomagnetic roll angle based on the giant magnetoresistive sensor.

(2)如图3流程2，采集各轴巨磁阻传感器的测量值，根据测量值转至图4流程，计算X轴、Y轴和Z轴上磁场分量H″′_X、H″′_Y、H″′_Z。(2)Process 2 as shown in Figure 3, collect the measured values of the giant magnetoresistive sensors of each axis, turn to the process in Figure 4 according to the measured values, and calculate the magnetic field components H″’_X , H″’_Y on the X-axis, Y-axis and Z-axis , H″′_Z .

如图4流程1，系统初始化，包括INA118放大倍数K，AAH002-02灵敏度S，激励电压V_b。Process 1 as shown in Figure 4, system initialization, including INA118 magnification K, AAH002-02 sensitivity S, excitation voltage V_b .

如图4流程2，分别采集X轴、Y轴和Z轴上巨磁阻传感器AAH002-02输出值ΔV_out。As shown inprocess 2 of Figure 4, the output values ΔV_out of the giant magnetoresistive sensor AAH002-02 on the X-axis, Y-axis and Z-axis are collected respectively.

如图4流程3，将ΔV_out、K、S及V_b带入等式ΔV_out＝KSHV_b，分别计算地磁场分量H″′_X、H″′_Y、H″′_Z。As shown inFlowchart 3 of Figure 4, ΔV_out , K, S and V_b are brought into the equation ΔV_out =KSHV_b to calculate the geomagnetic field components H″′_X , H″′_Y , and H″′_Z .

(3)如图3流程3，采集双轴加速度传感器的输出值，利用输出值，转至图5流程，计算俯仰角，实现了俯仰角θ唯一性。(3) As shown inprocess 3 of Figure 3, the output value of the biaxial acceleration sensor is collected, and the output value is used to go to the process of Figure 5 to calculate the pitch angle and realize the uniqueness of the pitch angle θ.

(4)计算横滚角

：(4) Calculate roll angle

:

如图5流程1，采集X轴和Z轴加速度传感器测量值为Ax、Az。As shown inprocess 1 of Figure 5, the measured values of the X-axis and Z-axis acceleration sensors are collected as Ax and Az.

如图5流程2，将Ax代入等式θ＝arcSin(Ax/g)计算俯仰角θ。As shown inprocess 2 of Figure 5, substitute Ax into the equation θ=arcSin(Ax/g) to calculate the pitch angle θ.

如图5流程3，当Ax大于0，Az大于0时，则所述θ为俯仰角。As shown inprocess 3 of FIG. 5 , when Ax is greater than 0 and Az is greater than 0, the θ is the pitch angle.

如图5流程4，当Ax大于0，Az小于0时，则180°-θ为俯仰角。As shown inprocess 4 of Figure 5, when Ax is greater than 0 and Az is less than 0, then 180°-θ is the pitch angle.

如图5流程5，当Ax小于0，Az小于0时，则180°+|θ|为俯仰角。As shown inprocess 5 of Figure 5, when Ax is less than 0 and Az is less than 0, then 180°+|θ| is the pitch angle.

如图5流程6，当Ax小于0，Az大于0时；则360°-|θ|为俯仰角。As shown in process 6 of Figure 5, when Ax is less than 0 and Az is greater than 0; then 360°-|θ| is the pitch angle.

如图3流程4，利用X轴、Y轴和Z轴地磁场分量H″′_X、H″′_Y和H″′_Z及俯仰角θ，通Process 4 as shown in Figure 3, using the X-axis, Y-axis and Z-axis geomagnetic field components H"'_X , H"'_Y and H"'_Z and the pitch angle θ, through

过式

(方位角为零)进行横滚角计算。Passed

(azimuth is zero) for roll angle calculate.

(5)输出横滚角

(5) Output roll angle

Claims

Translated fromChinese

1.一种基于巨磁阻传感器的地磁横滚角测量系统，由地磁测量模块(1)、俯仰角测量模块(2)、信号调理模块(3)和微处理器(4)组成，其特征在于所述地磁测量模块(1)包括两两正交的X轴、Y轴和Z轴巨磁阻传感器；所述俯仰角测量模块(2)包括互相垂直的X轴和Z轴双轴加速度传感器；所述信号调理模块(3)包括经过一个放大器偏置调零电路，一个仪表放大器，连接一个A/D转换器；所述地磁测量模块(1)经信号调理模块(3)连接所述微处理器(4)，所述俯仰角测量模块(2)连接所述微处理器(4)。1. A geomagnetic roll angle measurement system based on giant magnetoresistive sensor, composed of geomagnetic measurement module (1), pitch angle measurement module (2), signal conditioning module (3) and microprocessor (4), its features The geomagnetic measurement module (1) includes pairwise orthogonal X-axis, Y-axis and Z-axis giant magnetoresistive sensors; the pitch angle measurement module (2) includes mutually perpendicular X-axis and Z-axis biaxial acceleration sensors ; The signal conditioning module (3) includes an amplifier bias zeroing circuit, an instrumentation amplifier, and an A/D converter; the geomagnetic measurement module (1) is connected to the micro via a signal conditioning module (3) A processor (4), the pitch angle measurement module (2) is connected to the microprocessor (4).

2.根据权利要求1所述的基于巨磁阻传感器的地磁横滚角测量系统，其特征在于所述地磁测量模块(1)采用三轴巨磁阻传感器AAH002-02；所述俯仰角测量模块(2)采用双轴加速度传感器ADXL202；所述信号调理模块(3)中仪表放大器采用INA118，A/D转换器为微处理器自带；所述微处理器(4)采用Atmega128L；所述信号调理模块(3)对地磁测量模块(1)的巨磁阻传感器测得模拟信号进行放大、偏置调零和模数转换；所述微处理器(4)对地磁和俯仰信息进行多传感器融合处理后得到地磁横滚角。2. the geomagnetic roll angle measurement system based on giant magnetoresistance sensor according to claim 1, is characterized in that described geomagnetic measurement module (1) adopts three-axis giant magnetoresistance sensor AAH002-02; Described pitch angle measurement module (2) adopt biaxial acceleration sensor ADXL202; Instrument amplifier adopts INA118 in the described signal conditioning module (3), and A/D converter is that microprocessor carries; Described microprocessor (4) adopts Atmega128L; Described signal The conditioning module (3) amplifies the analog signal measured by the giant magnetoresistive sensor of the geomagnetic measurement module (1), offsets zeroing and analog-to-digital conversion; the microprocessor (4) performs multi-sensor fusion on the geomagnetic and pitch information After processing, the geomagnetic roll angle is obtained.

3.根据权利要求1所述的基于巨磁阻传感器的地磁横滚角测量系统，其特征在于所述信号调理模块(3)是将巨磁阻传感器模拟信号经放大器偏置调零电路后由仪表放大器放大，再通过A/D转换器转换为数字信号，最后送入微处理器；所述放大器偏置调零电路是：在所述仪表放大器一个输入端接一个数字电位器R_g，通过控制数字电位器R_g，实现电桥供电电压的调整，达到减小巨磁阻传感器零位输出的目的，提高了模数转换器的采样分辨率，从而提高了地磁场测量的精度。3. the geomagnetic roll angle measurement system based on giant magnetoresistance sensor according to claim 1, is characterized in that described signal conditioning module (3) is after the analog signal of giant magnetoresistance sensor is biased and zeroed by amplifier The instrumentation amplifier is amplified, then converted into a digital signal by the A/D converter, and finally sent to the microprocessor; the bias zeroing circuit of the amplifier is: a digital potentiometer R_g is connected to an input terminal of the instrumentation amplifier, and is controlled by The digital potentiometer R_g realizes the adjustment of the power supply voltage of the bridge, achieves the purpose of reducing the zero output of the giant magnetoresistive sensor, improves the sampling resolution of the analog-to-digital converter, and thus improves the accuracy of the geomagnetic field measurement.

4.一种基于巨磁阻传感器的地磁横滚角测量方法，采用根据权利要求1所述的基于巨磁阻传感器的地磁横滚角测量系统进行测量，其特征在于具体操作步骤如下：4. a method for measuring the geomagnetic roll angle based on the giant magnetoresistance sensor, adopting the geomagnetic roll angle measurement system based on the giant magnetoresistance sensor according to claim 1 to measure, is characterized in that the concrete operation steps are as follows:

(3)采集双轴加速度传感器的输出值，利用该输出值计算俯仰角，实现了俯仰角θ唯一性；(3) Gather the output value of the biaxial acceleration sensor, use the output value to calculate the pitch angle, and realize the uniqueness of the pitch angle θ;

进行方位角为零的横滚角

roll angle with zero azimuth

calculate;(5)输出横滚角

(5) Output roll angle

5.根据权利要求4所述的基于巨磁阻传感器的地磁横滚角测量方法，其特征在于所述步骤(2)中，AAH002-02传感器利用的是磁场的变化引起阻值的变化，电阻的变化引起惠斯通电桥输出的变化；利用下式ΔV_out＝KSHV_b分别计算X轴、Y轴和Z轴上磁场分量H″′_X、H″′_Y、H″′_Z。式中ΔV_out为AAH002-02输出量，K为INA118放大倍数，S为AAH002-02灵敏度，V_b为激励电压。5. The geomagnetic roll angle measurement method based on giant magnetoresistive sensor according to claim 4, characterized in that in the step (2), what the AAH002-02 sensor utilizes is that the variation of the magnetic field causes the variation of the resistance value, and the resistance The change of the Wheatstone bridge causes the output of the Wheatstone bridge to change; use the following formula ΔV_out = KSHV_b to calculate the magnetic field components on the X-axis, Y-axis and Z-axis respectively H″′_X , H″′_Y , H″′_Z . In the formula ΔV_out is the output of AAH002-02, K is the magnification of INA118, S is the sensitivity of AAH002-02, and V_b is the excitation voltage.

6.根据权利要求4所述的基于巨磁阻传感器的地磁横滚角测量方法，其特征在于所述步骤(3)中，由于单轴加速度传感器测量俯仰角时出现多值问题，采用双轴加速度传感器ADXL202，实现了俯仰角唯一性；具体步骤如下：设定Ax、Az为X轴和Z轴加速度。6. the geomagnetic roll angle measurement method based on giant magnetoresistive sensor according to claim 4, is characterized in that in described step (3), because multi-value problem occurs when uniaxial acceleration sensor measures pitch angle, adopts biaxial The acceleration sensor ADXL202 realizes the uniqueness of the pitch angle; the specific steps are as follows: set Ax and Az as the X-axis and Z-axis accelerations.

(1)微处理器(4)将Ax代入等式θ＝arcSin(Ax/g)计算俯仰角；(1) microprocessor (4) substitutes Ax into equation θ=arcSin(Ax/g) to calculate pitch angle;

(2)根据gSinθ＝Ax，gCosθ＝Az，有：(2) According to gSinθ=Ax, gCosθ=Az, there are:

当Ax大于0，Az大于0时，则所述θ为俯仰角；When Ax is greater than 0 and Az is greater than 0, then the θ is the pitch angle;

当Ax大于0，Az小于0时，则180°-θ为俯仰角；When Ax is greater than 0 and Az is less than 0, then 180°-θ is the pitch angle;

当Ax小于0，Az小于0时，则180°+|θ|为俯仰角；When Ax is less than 0 and Az is less than 0, then 180°+|θ| is the pitch angle;

当Ax小于0，Az大于0时；则360°-|θ|为俯仰角。When Ax is less than 0 and Az is greater than 0; then 360°-|θ| is the pitch angle.