互补滤波器陀螺仪加速度计

时间:2015-01-06 08:01:27

标签: android filter accelerometer gyroscope azimuth

我使用陀螺和加速度计的互补滤波器只是为了方位角...我已经从这个网站获得了它:http://www.thousand-thoughts.com/2012/03/android-sensor-fusion-tutorial/1/

过滤器的核心是:

         /*
         * Fix for 179° <--> -179° transition problem:
         * Check whether one of the two orientation angles (gyro or accMag) is negative while the other one is positive.
         * If so, add 360° (2 * math.PI) to the negative value, perform the sensor fusion, and remove the 360° from the result
         * if it is greater than 180°. This stabilizes the output in positive-to-negative-transition cases.
         */

        // azimuth
        if (gyroOrientation[0] < -0.5 * Math.PI && accMagOrientation[0] > 0.0) {
            fusedOrientation[0] = (float) (FILTER_COEFFICIENT * (gyroOrientation[0] + 2.0 * Math.PI) + oneMinusCoeff * accMagOrientation[0]);
            fusedOrientation[0] -= (fusedOrientation[0] > Math.PI) ? 2.0 * Math.PI : 0;
            Log.d("test","gyro Is Negative");
        }
        else if (accMagOrientation[0] < -0.5 * Math.PI && gyroOrientation[0] > 0.0) {
            fusedOrientation[0] = (float) (FILTER_COEFFICIENT * gyroOrientation[0] + oneMinusCoeff * (accMagOrientation[0] + 2.0 * Math.PI));
            fusedOrientation[0] -= (fusedOrientation[0] > Math.PI)? 2.0 * Math.PI : 0;
            Log.d("test","accel Is Negative");

        }
        else {
            fusedOrientation[0] = FILTER_COEFFICIENT * gyroOrientation[0] + oneMinusCoeff * accMagOrientation[0];
        }
        gyroMatrix = getRotationMatrixFromOrientation(fusedOrientation);
        System.arraycopy(fusedOrientation, 0, gyroOrientation, 0, 3);

我想将它与漂移的真实陀螺数据进行比较...... 为此,我使用了gyroOreintationReal ...并添加了一些代码来保存gyroOreintation,如下所示:

 if(initState) {
        float[] initMatrix = new float[9];
        initMatrix = getRotationMatrixFromOrientation(accMagOrientation);
        float[] test = new float[3];
        SensorManager.getOrientation(initMatrix, test);
        gyroMatrix = matrixMultiplication(gyroMatrix, initMatrix);
        gyroMatrixReal = matrixMultiplication(gyroMatrixReal, initMatrix);

        initState = false;
    }

    // copy the new gyro values into the gyro array
    // convert the raw gyro data into a rotation vector
    float[] deltaVector = new float[4];
    float[] deltaVectorReal = new float[4];

    if(timestamp != 0) {
        final float dT = (event.timestamp - timestamp) * NS2S;


    System.arraycopy(event.values, 0, gyro, 0, 3);
    System.arraycopy(event.values, 0, gyroReal, 0, 3);


    getRotationVectorFromGyro(gyro, deltaVector, dT / 2.0f);
    getRotationVectorFromGyro(gyroReal, deltaVectorReal, dT / 2.0f);

    }

    // measurement done, save current time for next interval
    timestamp = event.timestamp;

    // convert rotation vector into rotation matrix
    float[] deltaMatrix = new float[9];
    float[] deltaMatrixReal = new float[9];

    SensorManager.getRotationMatrixFromVector(deltaMatrix, deltaVector);
    SensorManager.getRotationMatrixFromVector(deltaMatrixReal, deltaVectorReal);


    // apply the new rotation interval on the gyroscope based rotation matrix
    gyroMatrix = matrixMultiplication(gyroMatrix, deltaMatrix);
    gyroMatrixReal = matrixMultiplication(gyroMatrixReal, deltaMatrixReal);


    // get the gyroscope based orientation from the rotation matrix
    SensorManager.getOrientation(gyroMatrix, gyroOrientation);
    SensorManager.getOrientation(gyroMatrixReal, gyroOrientationReal);     

我保存了结果并用matlab绘制了它们......但是图表显示陀螺的方向是负的...但是fuseOreientation小于+150并且加速方向略大于+150。 ..

我该如何解决问题? 我在补充过滤器的核心添加了一些代码:

//RealGyro
       if (gyroOrientationReal[0] < -0.5 * Math.PI && accMagOrientation[0] > 0.0) {
            gyroOrientationReal[0] =  (float) (gyroOrientation[0] + 2.0 * Math.PI);
            gyroOrientationReal[0] -= (gyroOrientationReal[0] > Math.PI) ? 2.0 * Math.PI : 0;
       }        

它有时候确定但是如果我有负的加速数据和正陀螺数据,我不知道该怎么办?

2 个答案:

答案 0 :(得分:0)

当我试图将手机旋转360度时......我从matlab得到了这个情节: http://www.uppic.com/uploads/14205374821.jpg

绿色单独用于陀螺仪,红色用于融合方向,蓝色用于加速。

  • 为什么Gyro的时间已经抵消?原因是漂移?情节是否正确?
  • 如何使用0-360周期而不是0_180和-180_0?

答案 1 :(得分:0)

您发布的图片的链接不起作用,因此我无法从matlab查看该图。 陀螺仪漂移不会为数据添加任何时间偏移。也许偏移是由一些内部延迟(不可能)引起的,或者更可能是由算法中的延迟引起的。我无法确切地说,因为我看不到,时间偏移有多大。

如果您想要陀螺仪数据,则无需添加到补充滤波器中。所有陀螺仪数据应该已经在gyroOrientationReal向量中。无需进一步处理。真正的陀螺仪数据不应受accMagOrientation的影响(如果gyroOrientationReal更改为accMagOrientation[0] > 0.0,则会影响您。

如果你想从[0,360]期间到[0,180,-180,0]期间,你只需要从你的结果中减去180,你就完成了。

我希望我可以帮助你。