九轴陀螺仪姿态解算c语言代码

以下是一个九轴陀螺仪姿态解算的C语言代码，基于卡尔曼滤波器，可以实现较为精确的姿态解算。

#include <math.h>

#define PI 3.14159265358979323846

// 加速度计、磁力计、陀螺仪数据
float Accel_X, Accel_Y, Accel_Z; 
float Mag_X, Mag_Y, Mag_Z; 
float Gyro_X, Gyro_Y, Gyro_Z;

// 磁力计校准参数
float Mag_Offset_X, Mag_Offset_Y, Mag_Offset_Z;
float Mag_Scale_X, Mag_Scale_Y, Mag_Scale_Z;

// 卡尔曼滤波器参数
float Q_angle = 0.001;   // 测量误差
float Q_gyro = 0.003;    // 陀螺仪误差
float R_angle = 0.5;     // 估计误差

float Angle_X, Angle_Y;  // 姿态角

float P_00 = 0, P_01 = 0, P_10 = 0, P_11 = 0;
float Q_bias = 0, Angle_err = 0;
float PCt_0, PCt_1, E, K_0, K_1, t_0, t_1;

void Kalman_Filter(float Accel_X, float Accel_Y, float Accel_Z, 
                   float Gyro_X, float Gyro_Y, float Gyro_Z, 
                   float Mag_X, float Mag_Y, float Mag_Z)
{
    float norm;
    float hx, hy, hz, bx, bz;
    float vx, vy, vz;
    float ex, ey, ez;

    // 磁力计校准
    Mag_X = (Mag_X - Mag_Offset_X) * Mag_Scale_X;
    Mag_Y = (Mag_Y - Mag_Offset_Y) * Mag_Scale_Y;
    Mag_Z = (Mag_Z - Mag_Offset_Z) * Mag_Scale_Z;

    // 计算加速度计和磁力计的模
    norm = sqrt(Accel_X * Accel_X + Accel_Y * Accel_Y + Accel_Z * Accel_Z);
    norm = 1.0 / norm;
    Accel_X *= norm;
    Accel_Y *= norm;
    Accel_Z *= norm;

    norm = sqrt(Mag_X * Mag_X + Mag_Y * Mag_Y + Mag_Z * Mag_Z);
    norm = 1.0 / norm;
    Mag_X *= norm;
    Mag_Y *= norm;
    Mag_Z *= norm;

    // 计算磁场的水平分量
    hx = 2 * Mag_X * (0.5 - Accel_Y * Accel_Y - Accel_Z * Accel_Z) + 2 * Mag_Y * (Accel_X * Accel_Y - Accel_Z * Accel_Z) + 2 * Mag_Z * (Accel_X * Accel_Z + Accel_Y * Accel_Z);
    hy = 2 * Mag_X * (Accel_X * Accel_Y + Accel_Z * Accel_Z) + 2 * Mag_Y * (0.5 - Accel_X * Accel_X - Accel_Z * Accel_Z) + 2 * Mag_Z * (Accel_Y * Accel_Z - Accel_X * Accel_Z);
    hz = 2 * Mag_X * (Accel_X * Accel_Z - Accel_Y * Accel_Z) + 2 * Mag_Y * (Accel_Y * Accel_Z + Accel_X * Accel_Z) + 2 * Mag_Z * (0.5 - Accel_X * Accel_X - Accel_Y * Accel_Y);
    bx = sqrt((hx * hx) + (hy * hy));
    bz = hz;

    // 计算陀螺仪的角速度
    Gyro_X -= Q_bias;
    Gyro_Y -= Q_bias;
    Gyro_Z -= Q_bias;
    vx = Gyro_X;
    vy = Gyro_Y;
    vz = Gyro_Z;

    // 计算估计的姿态角
    Angle_X += vx * dt;
    Angle_Y += vy * dt;

    // 计算估计的方差
    P_00 += dt * (dt * P_11 - P_01 - P_10 + Q_angle);
    P_01 -= dt * P_11;
    P_10 -= dt * P_11;
    P_11 += dt * (Q_gyro - P_11 * dt);

    // 计算卡尔曼增益
    PCt_0 = C_0 * P_00;
    PCt_1 = C_1 * P_10;
    E = R_angle + C_0 * PCt_0 + C_1 * PCt_1;
    K_0 = PCt_0 / E;
    K_1 = PCt_1 / E;

    // 计算角度误差
    Angle_err = Angle_X - hx * Angle_Y;

    // 更新估计值和方差
    Angle_X -= K_0 * Angle_err;
    Q_bias += K_1 * Angle_err;
    P_00 -= K_0 * PCt_0;
    P_01 -= K_0 * PCt_1;
    P_10 -= K_1 * PCt_0;
    P_11 -= K_1 * PCt_1;

    // 计算最终的姿态角
    Angle_X = Angle_X * 180 / PI;
    Angle_Y = Angle_Y * 180 / PI;
}

需要注意的是，这个代码只是一个简单的示例，实际应用中需要根据具体情况进行调整和优化。同时，由于九轴陀螺仪姿态解算涉及到多个传感器的数据处理和校准，因此在实际应用中需要注意数据的准确性和稳定性。