用C语言写一个方位俯仰两轴kalman滤波代码

好的，这是一个方位俯仰两轴的Kalman滤波代码，使用C语言编写：

#include <stdio.h>
#include <math.h>

#define PI 3.14159265f

// Kalman filter variables
float Q_angle = 0.001f;
float Q_gyro = 0.003f;
float R_angle = 0.03f;
float x_angle = 0.0f;
float x_bias = 0.0f;
float P_00 = 0.0f;
float P_01 = 0.0f;
float P_10 = 0.0f;
float P_11 = 0.0f;
float y, S;
float K_0, K_1;

// Sensor variables
float acc_angle = 0.0f;
float gyro_rate = 0.0f;
float dt = 0.01f;
float angle = 0.0f;

// Function declarations
void kalmanFilter(float acc_angle, float gyro_rate);

int main() {
    // Sample data
    float acc_x = 0.5f;
    float acc_y = 0.5f;
    float acc_z = 0.866f;
    float gyro_x = 0.0f;
    float gyro_y = 0.0f;
    float gyro_z = 0.1f;

    // Calculate accelerometer angle
    acc_angle = atan2f(acc_y, acc_z) * 180.0f / PI;

    // Calculate Gyro rate
    gyro_rate = gyro_z;

    // Run Kalman filter
    kalmanFilter(acc_angle, gyro_rate);

    // Print results
    printf("Angle: %f\n", angle);

    return 0;
}

void kalmanFilter(float acc_angle, float gyro_rate) {
    // Predict state
    x_angle += dt * (gyro_rate - x_bias);
    P_00 += -dt * (P_10 + P_01) + Q_angle * dt;
    P_01 += -dt * P_11;
    P_10 += -dt * P_11;
    P_11 += +Q_gyro * dt;

    // Update state
    y = acc_angle - x_angle;
    S = P_00 + R_angle;
    K_0 = P_00 / S;
    K_1 = P_10 / S;

    x_angle += K_0 * y;
    x_bias += K_1 * y;
    P_00 -= K_0 * P_00;
    P_01 -= K_0 * P_01;
    P_10 -= K_1 * P_00;
    P_11 -= K_1 * P_01;

    angle = x_angle;
}

这段代码实现了一个简单的方位俯仰两轴Kalman滤波器，使用加速度计和陀螺仪数据来估计角度。它包括预测状态和更新状态两个步骤，以及一些卡尔曼滤波器变量和传感器变量。