我必须从陀螺仪的智能手机输出中计算 Android 偏航、滚动、俯仰,我编写了以下代码:
if(event.sensor.getType()==Sensor.TYPE_GYROSCOPE){
float xgyr=event.values[0]; //rotation around x-axis [rad/sec]
float ygyr=event.values[1]; // rotation around y-axis
float zgyr=event.values[2]; // rotation around z-axis
// This timestep's delta rotation to be multiplied by the current rotation
// after computing it from the gyro sample data.
double EPSILON = 0.0; //EPSILON value to be defined
if (timestamp != 0) {
final float dT = (event.timestamp - timestamp) * NS2S;
// Axis of the rotation sample, not normalized yet.
float axisX = event.values[0];
float axisY = event.values[1];
float axisZ = event.values[2];
// Calculate the angular speed of the sample, teta is the vector length
float omegaMagnitude = (float) Math.sqrt(axisX*axisX + axisY*axisY + axisZ*axisZ);
// Normalize the rotation vector if it's big enough to get the axis
if (omegaMagnitude > EPSILON) { //EPSILON TO BE DEFINED
axisX /= omegaMagnitude;
axisY /= omegaMagnitude;
axisZ /= omegaMagnitude;
}
你好,我必须使用陀螺仪的输出来计算偏航角和俯仰角,我写了这段代码:
float thetaOverTwo = omegaMagnitude * dT / 2.0f; //Insert initial value for orientation omegaMagnitude
float sinThetaOverTwo = (float) Math.sin(thetaOverTwo);
float cosThetaOverTwo = (float) Math.cos(thetaOverTwo);
/*rotation vector, a non-normalized three-dimensional vector the direction of which specifies the rotation axis,
and the length of which is teta, Combining two consecutive quaternion rotations is therefore just as simple as using the rotation matrix.
Remember that two successive rotation matrices, A1 , A2 are combined A3 = A2*A1*/
//Quaternions
deltaRotationVector[0] = sinThetaOverTwo * axisX;
deltaRotationVector[1] = sinThetaOverTwo * axisY;
deltaRotationVector[2] = sinThetaOverTwo * axisZ;
deltaRotationVector[3] = cosThetaOverTwo;
}
timestamp = event.timestamp;
float[] deltaRotationMatrix = new float[9];
SensorManager.getRotationMatrixFromVector(deltaRotationMatrix, deltaRotationVector);
// User code should concatenate the delta rotation we computed with the current rotation
// in order to get the updated rotation.
// rotationCurrent = rotationCurrent * deltaRotationMatrix; The initial rotation has to be computedand then at each step updated
/*Rotation current is a vector with rotation on pitch, roll, yaw (3x1) multiplied by 3x3 rotation matrix i have the new orientation*/
/*In the "xyz (pitch-roll-yaw) convention," theta is pitch, psi is roll, and phi is yaw. */
double pitch = Math.atan2(deltaRotationMatrix[6], deltaRotationMatrix[7]);
double roll = Math.acos(deltaRotationMatrix[8]);
double yaw = - Math.atan2(deltaRotationMatrix[2], deltaRotationMatrix[5]);
我不知道问题出在哪里,但是我使用此代码获得的偏航、滚动、俯仰值是错误的,因为即使手机处于相同的方向,我也获得了完全不同的值。我从最后三行代码中的旋转矩阵计算它们。还有偏航的值,公式中写的俯仰滚转,是弧度吗?