My Algorithm to Calculate Position of Smartphone - Integrated Algorithm Based on Sensor Data and GPS

Addressing the Algorithm Issue:

The provided algorithm does not correctly calculate the final velocity (speed) of the device. To address this error, the following formula should be used:

finalvelocity = initialVelocity + Double.Parse(currentAcceleration) * (t);

Revised Algorithm:

The revised algorithm incorporates the corrected speed calculation and additional improvements to ensure accurate position estimation:

var prevLocation = ServerHandler.getLatestPosition(IMEI);
var newLocation = new ReceivedDataDTO()
{
    LocationDataDto = new LocationDataDTO(),
    UsersDto = new UsersDTO(),
    DeviceDto = new DeviceDTO(),
    SensorDataDto = new SensorDataDTO()
};

//First Reading
if (prevLocation.Latitude == null)
{
    //Save GPS Readings
    newLocation.LocationDataDto.DeviceId = ServerHandler.GetDeviceIdByIMEI(IMEI);
    newLocation.LocationDataDto.Latitude = Latitude;
    newLocation.LocationDataDto.Longitude = Longitude;
    newLocation.LocationDataDto.Acceleration = float.Parse(currentAcceleration);
    newLocation.LocationDataDto.Direction = float.Parse(currentDirection);
    newLocation.LocationDataDto.Speed = (float) 0.0;
    newLocation.LocationDataDto.ReadingDateTime = date;
    newLocation.DeviceDto.IMEI = IMEI;

    // saving to database
    ServerHandler.SaveReceivedData(newLocation);
    return;
}

//If Previous Position not NULL --> Calculate New Position

**//Algorithm Starts HERE**

var oldLatitude = Double.Parse(prevLocation.Latitude);
var oldLongitude = Double.Parse(prevLocation.Longitude);
var direction = Math.PI * Double.Parse(currentDirection) / 180.0;
Double initialVelocity = prevLocation.Speed;

//Get Current Time to calculate time Travelling - In seconds
var secondsTravelling = date - tripStartTime;
var t = secondsTravelling.TotalSeconds;

//Calculate Distance using physice formula, s= Vi * t + 0.5 *  a * t^2
var distanceTravelled = initialVelocity * t + 0.5 * Double.Parse(currentAcceleration) * t * t;

//Calculate the Final Velocity/ Speed of the device.
// this Final Velocity is the Initil Velocity of the next reading
//Physics Formula: Vf = Vi + a * t
var finalvelocity = initialVelocity + Double.Parse(currentAcceleration) * (t);

//Convert from Degree to Radians (For Formula)
oldLatitude = Math.PI * oldLatitude / 180;
oldLongitude = Math.PI * oldLongitude / 180;

//Calculate the New Longitude and Latitude
var newLatitude = Math.Asin(Math.Sin(oldLatitude) * Math.Cos(distanceTravelled / earthRadius) + Math.Cos(oldLatitude) * Math.Sin(distanceTravelled / earthRadius) * Math.Cos(direction));
var newLongitude = oldLongitude + Math.Atan2(Math.Sin(direction) * Math.Sin(distanceTravelled / earthRadius) * Math.Cos(oldLatitude), Math.Cos(distanceTravelled / earthRadius) - Math.Sin(oldLatitude) * Math.Sin(newLatitude));

//Convert From Radian to degree/Decimal
newLatitude = 180 * newLatitude / Math.PI;
newLongitude = 180 * newLongitude / Math.PI;

Incorporating Sensor Data Integration:

This algorithm utilizes both accelerometer and magnetometer data to calculate the direction of movement. The following steps outline the process:

1. Linear Acceleration: Use the accelerometer to calculate linear acceleration in x, y, and z axes.
2. Direction of Movement: Combine the accelerometer readings with the magnetometer readings to determine the direction of movement.
3. Velocity and Distance: Integrate the acceleration with respect to time to obtain velocity. Calculate distance using the velocity and time interval.
4. Final Position: Update the current position using the calculated distance and direction.

Additional Considerations:

1. Calibration: Calibrate the sensors periodically to ensure accuracy.
2. Filtering: Implement noise and drift filters to improve data quality.
3. Time Synchronization: Ensure accurate time synchronization between the sensors and the device's clock.
4. Regular GPS Updates: Periodically correct the position estimate using GPS updates.

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