Methods and systems for driver identification
A method of determining a position of a mobile device in a vehicle during a drive includes measuring at least one first acceleration magnitude of the mobile device in a gravity direction with at least one sensor of the mobile device, measuring at least one second acceleration magnitude of the mobile device in the gravity direction with the at least one sensor of the mobile device, the at least one second acceleration magnitude separated in time from the at least one first acceleration magnitude, comparing the at least one first acceleration magnitude with the at least one second acceleration magnitude, and based on a result of the comparing, predicting the position of the mobile device in the vehicle.
1. A method of determining a position of a mobile device in a vehicle during a drive, the method comprising:
receiving, from an accelerometer of the mobile device, at least one first acceleration magnitude of the mobile device in a direction of a gravity vector;
detecting that a front axle of the vehicle encountered a bump when the at least one first acceleration magnitude exceeds a first threshold value;
receiving, from the accelerometer of the mobile device, at least one second acceleration magnitude of the mobile device in the direction of the gravity vector, wherein the at least one second acceleration magnitude is received after the at least one first acceleration magnitude;
detecting that a rear axle of the vehicle encountered the bump when the at least one second acceleration magnitude exceeds a second threshold value;
predicting, in response to detecting that the front axle of the vehicle encountered the bump and the rear axle of the vehicle encountered the bump, the position of the mobile device in the vehicle using the at least one first acceleration magnitude and the at least one second acceleration magnitude, wherein predicting the position of the mobile device in the vehicle includes:
predicting that the mobile device is positioned in a front portion of the vehicle when a maximum value of the at least one first acceleration magnitude is approximately equal to a maximum value of the at least one second acceleration magnitude; and
predicting that the mobile device is positioned in a rear portion of the vehicle when the maximum value of the at least one first acceleration magnitude is less than a maximum value of the at least one second acceleration magnitude; and
storing, in memory, the prediction of the position of the mobile device in the vehicle.
2. The method of claim 1 , wherein the at least one first acceleration magnitude of the mobile device is received after an initial entry signal.
3. The method of claim 1 , wherein the at least one first acceleration magnitude of the mobile device is received prior to a terminal exit signal.
4. The method of claim 1 , further comprising:
identifying a time interval that occurs between detecting that the front axle of the vehicle encountered the bump and detecting that the rear axle of the vehicle encountered the bump; and
determining that the time interval is less than a threshold time interval.
5. The method of claim 1 , wherein the first threshold and the second threshold are different.
6. The method of claim 4 , wherein the threshold time interval is based on a speed of the vehicle and the a wheelbase of the vehicle.
7. The method of claim 1 , wherein the mobile device is not oriented to a reference frame of the vehicle.
8. The method of claim 1 , wherein first acceleration magnitudes of the at least one first acceleration magnitude received prior to an initial entry signal are discarded.
9. A mobile device, comprising:
an accelerometer; and
a processor, the processor configured to perform operations including:
receiving, from the accelerometer while the mobile device is disposed in a vehicle, at least one first acceleration magnitude of the mobile device in a direction of a gravity vector during a drive;
detecting that a front axle of the vehicle encountered a bump when the at least one first acceleration magnitude exceeds a first threshold value;
receiving, from the accelerometer, at least one second acceleration magnitude of the mobile device in a direction of the gravity vector, wherein the at least one second acceleration magnitude is received after the at least one first acceleration magnitude;
detecting that a rear axle of the vehicle encountered the bump when the at least one second acceleration magnitude exceeds a second threshold value; and
generating, in response to detecting that the front axle of the vehicle encountered the bump and the rear axle of the vehicle encountered the bump, a prediction of a position of the mobile device in the vehicle using the at least one first acceleration magnitude and the at least one second acceleration magnitude, wherein generating the prediction of the position of the mobile device in the vehicle includes:
predicting that the mobile device is positioned in a front portion of the vehicle when a maximum value of the at least one first acceleration magnitude is approximately equal to a maximum value of the at least one second acceleration magnitude; and
predicting that the mobile device is positioned in a rear portion of the vehicle when the maximum value of the at least one first acceleration magnitude is less than the maximum value of the at least one second acceleration magnitude; and
storing, in memory, the prediction of the position of the mobile device in the vehicle.
10. The mobile device of claim 9 , wherein the at least one first acceleration magnitude of the mobile device is received after an initial entry signal.
11. The mobile device of claim 9 , wherein the at least one first acceleration magnitude of the mobile device is received prior to a terminal exit signal.
12. The mobile device of claim 9 , wherein the operations further include:
identifying a time interval that occurs between detecting that the front axle of the vehicle encountered the bump and detecting that the rear axle of the vehicle encountered the bump; and
determining that the time interval is less than a threshold time interval.
13. The mobile device of claim 12 , wherein the threshold time interval is based on a speed of the vehicle and the a wheelbase of the vehicle.
14. The mobile device of claim 9 , wherein the mobile device is not oriented to a reference frame of the vehicle.
15. The mobile device of claim 9 , wherein first acceleration magnitudes of the at least one first acceleration magnitude received prior to an initial entry signal are discarded.
16. The mobile device of claim 9 , wherein the first threshold and the second threshold are different.