即使 phone 精度很高，使用 GPS 的距离计算错误

Question

我在为我的一个应用 P-Cab 计算以公里为单位的距离时遇到问题。对于 driver 应用程序，我输入了上车地点，然后 driver 开始开车。并根据 "KM" 次出行，向用户收取出租车费。为了获得最佳结果，我每隔一分钟计算一次距离，这样我每隔一分钟就会得到一次取件位置，并且我会在每一分钟内添加所覆盖的距离。我遇到的问题是大多数时候，GPS 定位错误，因此对于 5 公里的骑行，它给出的结果为 10KM 或 15KM。

以下是我用来获取 GPS 的服务：

// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 4; // 10 meters

// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 10 * 1; // 1 minute

// Declaring a Location Manager
protected LocationManager locationManager;

public GPSTracker(Context context) {
    this.mContext = context;
    getLocation();
}

public Location getLocation() {
    try {
        Criteria criteria = new Criteria();
        criteria.setAccuracy(Criteria.ACCURACY_FINE);
        locationManager = (LocationManager) mContext
                .getSystemService(LOCATION_SERVICE);
        String provider = locationManager.getBestProvider(criteria, true);
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

        }
        // getting GPS status
        isGPSEnabled = locationManager
                .isProviderEnabled(LocationManager.GPS_PROVIDER);

        // getting network status
        isNetworkEnabled = locationManager
                .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

        if (!isGPSEnabled && !isNetworkEnabled) {
            // no network provider is enabled
        } else {
            this.canGetLocation = true;
            // First get location from Network Provider
            if (isNetworkEnabled) {
                locationManager.requestLocationUpdates(
                        LocationManager.NETWORK_PROVIDER,
                        MIN_TIME_BW_UPDATES,
                        MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                Log.d("Network", "Network");
                if (locationManager != null) {
                    location = locationManager.getLastKnownLocation(provider);
                    if (location != null) {
                        latitude = location.getLatitude();
                        longitude = location.getLongitude();
                    }
                }
            }
            // if GPS Enabled get lat/long using GPS Services
            if (isGPSEnabled) {
                if (location == null) {
                    locationManager.requestLocationUpdates(
                            LocationManager.GPS_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                    Log.d("GPS Enabled", "GPS Enabled");
                    if (locationManager != null) {
                        location = locationManager.getLastKnownLocation(provider);
                        if (location != null) {
                            latitude = location.getLatitude();
                            longitude = location.getLongitude();
                        }
                    }
                }
            }
        }

    } 
    return location;
   }
}

Answer 1

您计算距离的方法给出了空中距离。直接从源头到目的地，而不是路线距离。您将不得不使用 google 个地方 API:

字符串 url=https://maps.googleapis.com/maps/api/distancematrix/json";

这里需要传入origin,destinations,mode三个参数，产地：原产地，目的地：目的地位置，模式：在你的情况下它将是驾驶。

完整的 url 将是：

https://maps.googleapis.com/maps/api/distancematrix/json?units=imperial&origins=Washington,DC&destinations=New+York+City,NY&key=YOUR_API_KEY

即使 phone 精度很高，使用 GPS 的距离计算错误

Distance calculation error by using GPS even though phone is on high accuracy

java

gps

android

android-gps