IMU.c（参考匿名的）

#include "imu.h"#include "MPU6050.h"#include "math.h"#define RtA         57.324841               //弧度到角度#define AtR     0.0174533               //度到角度#define Acc_G   0.0011963               //加速度变成G#define Gyro_G  0.0610351               //角速度变成度   此参数对应陀螺2000度每秒#define Gyro_Gr 0.0010653               //角速度变成弧度   此参数对应陀螺2000度每秒#define FILTER_NUM 20S_INT16_XYZ ACC_AVG;            //平均值滤波后的ACCS_FLOAT_XYZ GYRO_I;             //陀螺仪积分S_FLOAT_XYZ EXP_ANGLE;      //期望角度S_FLOAT_XYZ DIF_ANGLE;      //期望角度与实际角度差S_FLOAT_XYZ Q_ANGLE;            //四元数计算出的角度int16_t ACC_X_BUF[FILTER_NUM],ACC_Y_BUF[FILTER_NUM],ACC_Z_BUF[FILTER_NUM];  //加速度滑动窗口滤波数组//filter是滤波的意思void Prepare_Data(void){    static uint8_t filter_cnt=0;    int32_t temp1=0,temp2=0,temp3=0;    uint8_t i;    MPU6050_Read();    MPU6050_Dataanl();    ACC_X_BUF[filter_cnt] = MPU6050_ACC_LAST.X;//更新滑动窗口数组    ACC_Y_BUF[filter_cnt] = MPU6050_ACC_LAST.Y;    ACC_Z_BUF[filter_cnt] = MPU6050_ACC_LAST.Z;    for(i=0;i<FILTER_NUM;i++)    {        temp1 += ACC_X_BUF[i];        temp2 += ACC_Y_BUF[i];        temp3 += ACC_Z_BUF[i];    }    ACC_AVG.X = temp1 / FILTER_NUM;    ACC_AVG.Y = temp2 / FILTER_NUM;    ACC_AVG.Z = temp3 / FILTER_NUM;    filter_cnt++;    if(filter_cnt==FILTER_NUM)  filter_cnt=0;    //GYRO_I.X += MPU6050_GYRO_LAST.X*Gyro_G*0.001;//0.001是时间间隔,两次prepare的执行周期    //GYRO_I.Y += MPU6050_GYRO_LAST.Y*Gyro_G*0.001;//这里已经使用四元数进行结算，因此不用直接累加    GYRO_I.Z += MPU6050_GYRO_LAST.Z*Gyro_G*0.001;}void Get_Attitude(void){    IMUupdate(MPU6050_GYRO_LAST.X*Gyro_Gr,                        MPU6050_GYRO_LAST.Y*Gyro_Gr,                        MPU6050_GYRO_LAST.Z*Gyro_Gr,                        ACC_AVG.X,ACC_AVG.Y,ACC_AVG.Z); //*0.0174转成弧度=π%180}////////////////////////////////////////////////////////////////////////////////#define Kp 10.0f                        // proportional gain governs rate of convergence to accelerometer/magnetometer#define Ki 0.008f                          // integral gain governs rate of convergence of gyroscope biases#define halfT 0.001f                   // half the sample period采样周期的一半float q0 = 1, q1 = 0, q2 = 0, q3 = 0;    // quaternion elements representing the estimated orientationfloat exInt = 0, eyInt = 0, ezInt = 0;    // scaled integral errorvoid IMUupdate(float gx, float gy, float gz, float ax, float ay, float az){  float norm;//  float hx, hy, hz, bx, bz;  float vx, vy, vz;// wx, wy, wz;  float ex, ey, ez;  // 先把这些用得到的值算好  float q0q0 = q0*q0;  float q0q1 = q0*q1;  float q0q2 = q0*q2;//  float q0q3 = q0*q3;  float q1q1 = q1*q1;//  float q1q2 = q1*q2;  float q1q3 = q1*q3;  float q2q2 = q2*q2;  float q2q3 = q2*q3;  float q3q3 = q3*q3;    if(ax*ay*az==0)        return;  norm = sqrt(ax*ax + ay*ay + az*az);       //acc数据归一化  ax = ax /norm;  ay = ay / norm;  az = az / norm;  // estimated direction of gravity and flux (v and w)              估计重力方向和流量/变迁  vx = 2*(q1q3 - q0q2);                                             //四元素中xyz的表示  vy = 2*(q0q1 + q2q3);  vz = q0q0 - q1q1 - q2q2 + q3q3 ;  // error is sum of cross product between reference direction of fields and direction measured by sensors  ex = (ay*vz - az*vy) ;                                             //向量外积在相减得到差分就是误差  ey = (az*vx - ax*vz) ;  ez = (ax*vy - ay*vx) ;  exInt = exInt + ex * Ki;                                //对误差进行积分  eyInt = eyInt + ey * Ki;  ezInt = ezInt + ez * Ki;  // adjusted gyroscope measurements  gx = gx + Kp*ex + exInt;                                              //将误差PI后补偿到陀螺仪，即补偿零点漂移  gy = gy + Kp*ey + eyInt;  gz = gz + Kp*ez + ezInt;                                          //这里的gz由于没有观测者进行矫正会产生漂移，表现出来的就是积分自增或自减  // integrate quaternion rate and normalise                           //四元素的微分方程  q0 = q0 + (-q1*gx - q2*gy - q3*gz)*halfT;  q1 = q1 + (q0*gx + q2*gz - q3*gy)*halfT;  q2 = q2 + (q0*gy - q1*gz + q3*gx)*halfT;  q3 = q3 + (q0*gz + q1*gy - q2*gx)*halfT;  // normalise quaternion  norm = sqrt(q0*q0 + q1*q1 + q2*q2 + q3*q3);  q0 = q0 / norm;  q1 = q1 / norm;  q2 = q2 / norm;  q3 = q3 / norm;  Q_ANGLE.Z = GYRO_I.Z;//atan2(2 * q1 * q2 + 2 * q0 * q3, -2 * q2*q2 - 2 * q3* q3 + 1)* 57.3; // yaw  Q_ANGLE.Y = asin(-2 * q1 * q3 + 2 * q0* q2)* 57.3; // pitch  Q_ANGLE.X = atan2(2 * q2 * q3 + 2 * q0 * q1, -2 * q1 * q1 - 2 * q2* q2 + 1)* 57.3; // roll}