- 作者:老汪软件技巧
- 发表时间:2024-11-01 21:02
- 浏览量:
因为项目需要利用到了Android手机中的加速度传感器来获取三个加速度轴的加速度大小,同时也可以实现自定义采样频率,这个我写了一个类,通过类来控制。
获取加速度数据总体来说比较简单,首先获取服务:
SensorManager sm = (SensorManager) getSystemService(SENSOR_SERVICE);
然后在onResume()方法中注册监听器,开始使用加速度传感器:
sm.registerListener(this, SensorManager.SENSOR_ORIENTATION
| SensorManager.SENSOR_ACCELEROMETER,
simpleRate.get_SENSOR_RATE_FAST());
接着是很重要的一步,在onDestory()方法中解除监听器,不然加速度传感器会一直工作,很浪费电。还有需要注意的是,手机屏幕暗掉的时候,加速度传感器还是会工作的,如果想要屏幕暗掉的时候加速度传感器步工作,则需要在onPause()方法中解除监听器。
@Override
protected void onStop() {
// unregister listener
sm.unregisterListener(this);
super.onStop();
}
接下来是自定义采样频率:
注册监听器的时候最后一个参数是延迟时间,其实也就是采样频率,单位是微秒。只需要写入数字即可控制采样频率,这里通过一个类实现:
SimpleRate.java
package com.llp.classdifine;
/**
* 加速度传感器采样率设定
*
* @author Liu_Longpo
*
*/
public class SimpleRate {
/**
* 50Hz
*/
private int SENSOR_RATE_NORMAL = 20000;
/**
* 80Hz
*/
private int SENSOR_RATE_MIDDLE = 12500;
/**
* 100Hz
*/
private int SENSOR_RATE_FAST = 10000;
public SimpleRate() {
};
/**
* 50Hz
* @return
*/
public int get_SENSOR_RATE_NORMAL() {
return this.SENSOR_RATE_NORMAL;
}
/**
* 80Hz
*
* @return
*/
public int get_SENSOR_RATE_MIDDLE() {
return this.SENSOR_RATE_MIDDLE;
}
/**
* 100Hz
*
* @return
*/
public int get_SENSOR_RATE_FAST() {
return this.SENSOR_RATE_FAST;
}
}
MainActivity.java 代码如下:
package com.llp.acceleration;
import java.io.File;
import java.util.ArrayList;
import android.app.Activity;
import android.hardware.SensorListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.llp.classdifine.FileService;
import com.llp.classdifine.SimpleRate;
public class MainActivity extends Activity implements SensorListener {
SensorManager sm = null;
TextView acx = null;
TextView acy = null;
TextView o = null;
EditText fileName;
EditText contentWrite;
Button btnSave;
Button btnRead;
EditText contentRead;
String mfileName;
private FileService fileService;
double ax = 0;
double ay = 0;
double oy = 0;
double oz = 0;
double axp = 0;
double ayp = 0;
double g = 10;
double gp = 0;
/**
* 采样频率设定
*/
public SimpleRate simpleRate;
// ArrayList mDataListX = new ArrayList();
// ArrayList mDataListY = new ArrayList();
// ArrayList mDataListZ = new ArrayList();
double tmp1 = 0, tmp2 = 0, tmp3 = 0, tmp4 = 0;
/**
* 获取X轴加速度
*
* @return
*/
public double getAccelerationX() {
return axp;
}
/**
* 获取Y轴加速度
*
* @return
*/
public double getAccelerationY() {
return ayp;
}
/**
* 获取Z轴加速度
*
* @return
*/
public double getOrientation() {
return Math.asin(tmp4) / Math.PI * 180.0;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// get reference to SensorManager
simpleRate = new SimpleRate();
sm = (SensorManager) getSystemService(SENSOR_SERVICE);
setContentView(R.layout.activity_main);
/**
* 创建文件夹
*/
File sd = Environment.getExternalStorageDirectory();
String mPath = sd.getPath() + "/datas";
File file = new File(mPath);
if (!file.exists()) {
file.mkdir();
}
/**
* 控件初始化
*/
initView();
btnSave.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
mfileName = fileName.getText().toString();
// saveAcceleration(mfileName);
}
});
}
/**
* 保存加速度数据
*
* @param FileName
* @param content
*/
public void saveAcceleration(String FileName, String content) {
try {
// 判断sd卡是否存在手机上并且可以进行读写
if (Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED)) {
fileService.write2Path(FileName, content);
} else {
}
} catch (Exception e) {
Log.v("test", e.toString());
}
}
public void initView() {
acx = (TextView) findViewById(R.id.xbox);
acy = (TextView) findViewById(R.id.ybox);
o = (TextView) findViewById(R.id.obox);
fileName = (EditText) findViewById(R.id.fileName);
contentWrite = (EditText) findViewById(R.id.content);
btnSave = (Button) findViewById(R.id.btnsave);
btnRead = (Button) findViewById(R.id.btnread);
contentRead = (EditText) findViewById(R.id.contentread);
}
public void onSensorChanged(int sensor, float[] values) {
synchronized (this) {
if (sensor == SensorManager.SENSOR_ORIENTATION) {
oy = values[1];
oz = values[2];
}
if (sensor == SensorManager.SENSOR_ACCELEROMETER) {
ax = values[0];
ay = values[1];
}
tmp1 = Math.sin(oz * Math.PI / 180.0);
tmp2 = Math.sin(Math.abs(oy) * Math.PI / 180.0);
tmp3 = Math.sqrt(tmp1 * tmp1 + tmp2 * tmp2);
tmp4 = tmp1 / tmp3;
gp = 10 * tmp3;
axp = ax * Math.cos(tmp4) + ay * Math.sin(tmp4);
ayp = -ax * Math.sin(tmp4) + ay * Math.cos(tmp4) + gp;
acx.setText("a X: " + getAccelerationX());
acy.setText("a Y: " + getAccelerationY());
o.setText("Orientation : " + getOrientation());
// mDataListX.add(getAccelerationX() + "\n");
// mDataListY.add(getAccelerationY() + "\n");
// mDataListZ.add(getOrientation() + "\n");
}
}
public void onAccuracyChanged(int sensor, int accuracy) {
}
@Override
protected void onResume() {
super.onResume();
// register this class as a listener for the orientation and
// accelerometer sensors
sm.registerListener(this, SensorManager.SENSOR_ORIENTATION
| SensorManager.SENSOR_ACCELEROMETER,
simpleRate.get_SENSOR_RATE_FAST());
}
@Override
protected void onStop() {
// unregister listener
sm.unregisterListener(this);
super.onStop();
}
}
通过采集的x\y\z方向的数据计算出角度的算法如下
方法1:
fun calculation(x: Float, y: Float, z: Float): Float {
val value = (abs(x.toDouble()) / 10f).toFloat()
var angle: Float
//值大于1 反三角函数无法计算需要特殊处理
angle = if (value >= 1) {
90f
} else {
Math.toDegrees(asin(value.toDouble())).toFloat()
}
if (isLeft(x)) {
if (angle>15){
angle=15f
}
angle = -angle
}
return angle
}
/**
* 是否向左倾
*
* @return true 向左倾 false向右倾
*/
fun isLeft(x: Float): Boolean {
return x < 0
}
方法2:
fun calculateAngle(px: Float, py: Float): Double {
val value = (abs(px.toDouble()) / 10f).toFloat()
var angle =Math.toDegrees(value.toDouble())
if (px<0){
if (Math.abs(angle)>mMaxAngle){
angle= (-45).toDouble()
}
angle=-angle
}else{
if (Math.abs(angle)>mMaxAngle){
angle= (45).toDouble()
}
}
return angle
}
方法3:
private fun calculationHorizontal(x: Float): Float {
val value = (abs(x.toDouble()) / 10f).toFloat()
var angle: Float
//值大于1 反三角函数无法计算需要特殊处理
angle = if (value >= 1) {
90f
} else {
Math.toDegrees(asin(value.toDouble())).toFloat()
}
val isLeft = x < 0
if (isLeft) {
angle = -angle
}
return angle
}
最后打印效果