Detecting falls using a mobile device

1. A method comprising:

obtaining, by a mobile device, sample data generated by one or more sensors over a period of time, wherein the one or more sensors are worn by a user;

determining, by the mobile device, that the user has fallen based on the sample data;

determining, by the mobile device based on the sample data, a severity of an injury suffered by the user; and

generating, by the mobile device, one or more notifications based on the determination that the user has fallen and the determined severity of the injury.

2. The method of claim 1 , wherein the one or more sensors comprise at least one of an accelerometer, an orientation sensor, or an altimeter.

3. The method of claim 2 , wherein the sample data comprises motion data indicating a motion of the user over the period of time, and

wherein determining that the user has fallen comprises:

determining, based on the motion data, a first impact experienced by the user during the period of time, and

determining, based on the motion data, a change in orientation of a portion of the user's body during the period of time.

4. The method of claim 3 , wherein the portion of the user's body comprises the user's wrist.

5. The method of claim 3 , wherein the motion data comprises:

a first signal indicating an acceleration measured by the accelerometer over the period of time, and

a second signal indicating an orientation measured by the orientation sensor over the period of time.

6. The method of claim 5 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, a severity of the first impact experienced by the user.

7. The method of claim 6 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, that the user experienced multiple impacts including the first impact during the period of time.

8. The method of claim 7 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, a first set of characteristics associated with the first impact;

determining, based on the first signal and the second signal, a second set of characteristics associated with a second impact experienced by the user during the period of time; and

determining a similarity between the first set of characteristics and the second set of characteristics.

9. The method of claim 7 , wherein the motion data further comprises a third signal indicating an altitude measured by the altimeter over the period of time.

10. The method of claim 9 , wherein determining the severity of the injury suffered by the user further comprises:

determining, based on the third signal, a distance fallen by the user over the period of time.

11. The method of claim 10 , wherein determining the severity of the injury suffered by the user further comprises:

determining the severity of the injury based on the determined severity of the impact experienced by user and the determined distance fallen by the user.

12. The method of claim 1 , wherein generating the one or more notifications comprises:

transmitting a first notification to a communications device remote from the mobile device, the first notification comprising an indication that the user has fallen and an indication of the determined severity of the injury suffered by the user.

13. The method of claim 12 , wherein the communications device is an emergency response system.

14. The method of claim 1 , wherein the mobile device is a wearable mobile device.

15. The method of claim 1 , wherein at least some of the one or more sensors are disposed on or in the mobile device.

16. The method of claim 1 , wherein at least some of the one or more sensors are remote from the mobile device.

17. A system comprising:

one or more processors; and

one or more non-transitory computer readable media storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:

obtaining, by a mobile device, sample data generated by one or more sensors over a period of time, wherein the one or more sensors are worn by a user;

determining, by the mobile device, that the user has fallen based on the sample data;

determining, by the mobile device based on the sample data, a severity of an injury suffered by the user; and

generating, by the mobile device, one or more notifications based on the determination that the user has fallen and the determined severity of the injury.

18. The system of claim 17 , wherein the one or more sensors comprise at least one of an accelerometer, an orientation sensor, or an altimeter.

19. The system of claim 18 , wherein the sample data comprises motion data indicating a motion of the user over the period of time, and

wherein determining that the user has fallen comprises:

determining, based on the motion data, a first impact experienced by the user during the period of time, and

determining, based on the motion data, a change in orientation of a portion of the user's body during the period of time.

20. The system of claim 19 , wherein the portion of the user's body comprises the user's wrist.

21. The system of claim 19 , wherein the motion data comprises:

a first signal indicating an acceleration measured by the accelerometer over the period of time, and

a second signal indicating an orientation measured by the orientation sensor over the period of time.

22. The system of claim 21 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, a severity of the first impact experienced by the user.

23. The system of claim 22 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, that the user experienced multiple impacts including the first impact during the period of time.

24. The system of claim 23 , wherein determining the severity of the injury suffered by the user comprises:

determining, based on the first signal and the second signal, a first set of characteristics associated with the first impact;

determining, based on the first signal and the second signal, a second set of characteristics associated with a second impact experienced by the user during the period of time; and

determining a similarity between the first set of characteristics and the second set of characteristics.

25. The system of claim 23 , wherein the motion data further comprises a third signal indicating an altitude measured by the altimeter over the period of time.

26. The system of claim 25 , wherein determining the severity of the injury suffered by the user further comprises:

determining, based on the third signal, a distance fallen by the user over the period of time.

27. The system of claim 26 , wherein determining the severity of the injury suffered by the user further comprises:

determining the severity of the injury based on the determined severity of the impact experienced by user and the determined distance fallen by the user.

28. The system of claim 17 , wherein generating the one or more notifications comprises:

transmitting a first notification to a communications device remote from the mobile device, the first notification comprising an indication that the user has fallen and an indication of the determined severity of the injury suffered by the user.

29. The system of claim 28 , wherein the communications device is an emergency response system.

30. The system of claim 17 , wherein the mobile device is a wearable mobile device.

31. The system of claim 17 , wherein at least some of the one or more sensors are disposed on or in the mobile device.

32. The system of claim 17 , wherein at least some of the one or more sensors are remote from the mobile device.