Sensor based activity detection

• US 8,560,229 B1
• Filed: 09/15/2010
• Issued: 10/15/2013
• Est. Priority Date: 09/15/2010
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Lee, Steven, Park, Timothy Fulton
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US12/882,433
• Time in Patent Office: 1,126 Days
• Field of Search: 701/400, 701408-412, 701/468, 701/500, 701/516, 701433- 4, 345156-158, 340/988
• US Class Current: 701/433
• CPC Class Codes: G01C 21/20 Instruments for performing navigational calculations G01C21/24, G01C21/26 take precedence

Abstract

A sensor is used to detect movement of a mobile device. For example, data received from an accelerometer may be averaged together and compared to a threshold value. If the average of the data is greater than a threshold value, the mobile device may be assumed to be moving. This information may be used to control the frequency of data collection by, for example, a GPS receiver in order to maximize utility and minimize power use.

Claims

1. A method of determining if a client device is moving, the method comprising:

receiving N data points from an accelerometer of the client device;

determining, by a processor of the client device, an average of the N data points;

determining, if the average is greater than a threshold value, that the client device is moving; and

activating, in response to determining that the client device is moving, a location determination device to generate geographic location information associated with the client device.

2. The method of claim 1, wherein the location determination device is a GPS receiver and the generated geographic location information includes GPS latitude and longitude coordinate pairs.

3. The method of claim 2, further comprising determining a path of travel associated with the client device based on the GPS coordinates.

4. The method of claim 3, further comprising storing the path of travel at the client device.

5. The method of claim 3, further comprising displaying the path of travel on a display of the client device.

6. The method of claim 2, further comprising:

determining a location visited by the client device based on the GPS coordinates; and

transmitting the location to a server computer.

7. The method of claim 6, further comprising receiving, from the server, a recommended location based on the transmitted location.

8. The method of claim 1, further comprising:

receiving an additional data point from the accelerometer;

removing an oldest data point from the N data points to obtain N−

1 data points;

determining a second average of the additional data point and the N−

1 data points; and

determining, by a processor of the client device, that the client device is moving if the second average is greater than the threshold value.

9. The method of claim 1, wherein the threshold value describes a limit associated with an average force identified by the accelerometer based on a user'"'"'s motion.

10. A device to detect movement of a user, the device comprising:

an accelerometer for detecting data points;

memory for storing a last N detected data points;

a location determination device; and

a processor coupled to the accelerometer, the memory, and the location determination device, the processor configured to;

receive the last N detected data points from the accelerometer of the device;

store the last N detected data points in the memory;

determine an average of the last N detected data points;

determine, if the average is greater than a threshold value, that the device is moving; and

activate, in response to determining that the device is moving, a location determination device to generate geographic location information associated with the device.

11. The device of claim 10, wherein the location determination device is a GPS receiver and the generated geographic location information includes GPS latitude and longitude coordinate pairs.

12. The device of claim 11, wherein the processor is further configured to determine a path of travel associated with the device based on the GPS coordinates.

13. The device of claim 12, wherein the processor is further configured to store the path of travel in the memory.

14. The device of claim 12, the device further comprising a display, and wherein the processor is further configured to display the path of travel on the display.

15. The device of claim 11, wherein the processor is further configured to:

determine a location visited by the device based on the GPS coordinates; and

transmit the location to a server computer.

16. The device of claim 15, wherein the processor is further configured to receive, from the server computer, a recommended location based on the transmitted location.

17. The device of claim 10, wherein the processor is further configured to:

receive an additional data point from the accelerometer;

remove an oldest data point from the last N detected data points to obtain N−

1 data points;

determine a second average of the additional data point and the N−

1 data points; and

determine that the device is moving if the second average is greater than the threshold value.

18. The device of claim 10, wherein the threshold value describes a limit associated with an average force identified by the accelerometer based on the device'"'"'s motion.