Capacitive vehicle entry control

Patent metadata

Field	Value
Publication number	US-9953476-B2
Application number	US-201615204036-A
Country	US
Kind code	B2
Filing date	Jul 7, 2016
Priority date	Jul 7, 2016
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

An illustrative example method of operating a capacitive vehicle entry control device includes: determining a plurality of capacitance values of the vehicle entry control device during a measurement period; determining an average capacitance of the plurality of capacitance values; determining whether the determined average capacitance exceeds an average threshold; determining a range of the plurality of capacitance values; determining whether the determined range exceeds a range threshold; and initiating a vehicle entry process when the determined average capacitance exceeds the average threshold or when the determined range exceeds the range threshold.

First claim

We claim:

1. A method of operating a capacitive vehicle entry control device, the method comprising:
determining a plurality of capacitance values of the vehicle entry control device during a measurement period;
determining an average capacitance of the plurality of capacitance values;
determining whether the determined average capacitance exceeds an average threshold;
determining a range of the plurality of capacitance values;
determining whether the determined range exceeds a range threshold; and
initiating a vehicle entry process when the determined average capacitance exceeds the average threshold or when the determined range exceeds the range threshold, wherein initiating the vehicle entry process comprises attempting to detect a signaling device in a vicinity of the vehicle entry control device, transmitting a signal to an authorization signaling device, and determining that vehicle entry is authorized when an authorizing response is received from the authorization signaling device.

2. The method of claim 1 , comprising
determining that a false positive condition occurs when the vehicle entry process remains incomplete after the initiating; and
increasing at least one of the average threshold or the range threshold from an initial preselected value by a preselected increment when the false positive condition occurs.

3. The method of claim 2 , comprising
increasing the at least one of the average threshold or the range threshold responsive to each of a series of false positive conditions until a preselected upper limit on the at least one of the average threshold or the range threshold is reached.

4. The method of claim 2 , comprising
increasing the at least one of the average threshold or the range threshold responsive to each of a series of false positive conditions until the false positive condition stops occurring.

5. The method of claim 4 , comprising
resetting the at least one of the average threshold or the range threshold to the initial preselected value after a predetermined time has passed since a most recent detection of a change in the capacitance.

6. The method of claim 1 , comprising
determining that the vehicle entry process is successful after the initiating;
determining a first difference between the determined average and the average threshold corresponding to the successful vehicle entry process;
determining a second difference between the determined range and the range threshold corresponding to the successful vehicle entry process; and
decreasing the average threshold by a preselected amount when the first difference is less than the second difference or decreasing the range threshold by a preselected amount when the second difference is less than the first difference.

7. The method of claim 1 , wherein
the capacitive vehicle entry control device is associated with a vehicle door handle;
initiating the vehicle entry process includes determining that an authorized signaling device is near the vehicle door handle prior to unlocking the door; and
the method comprises

determining that a user attempted to manipulate the vehicle door handle before the vehicle door was unlocked;
determining a rate of change in the determined plurality of capacitance values preceding the user attempt to manipulate the vehicle door handle; and
using the determined rate of change for at least one subsequent determination whether to initiate the vehicle entry process.

8. The method of claim 7 , wherein using the determined rate of change for at least one subsequent determination whether to initiate the vehicle entry process comprises:
defining a user rate of change based on the determined rate of change;
determining a subsequent plurality of capacitance values;
determining a subsequent rate of change of at least some of the subsequent plurality of capacitance values; and
initiating the vehicle entry process when the determined subsequent rate of change corresponds to the user rate of change.

9. A capacitive vehicle entry control device, comprising:
at least one capacitive sensor having a capacitance that changes responsive to the presence of a portion of an individual's body; and
a controller comprising a processor and memory associated with the processor, the controller being configured to
determine a plurality of capacitance values of the vehicle entry control device during a measurement period;
determine an average capacitance of the plurality of capacitance values;
determine whether the determined average capacitance exceeds an average threshold;
determine a range of the plurality of capacitance values;
determine whether the determined range exceeds a range threshold; and
initiate a vehicle entry process when the determined average capacitance exceeds the average threshold or when the determined range exceeds the range threshold, wherein the controller is configured to initiate the vehicle entry process by attempting to detect a signaling device in a vicinity of the vehicle entry control device, transmitting a signal to an authorization signaling device, and determining that vehicle entry is authorized when an authorizing response is received from the authorization signaling device.

10. The device of claim 9 , wherein the controller is configured to
determine that a false positive condition occurs when the vehicle entry process remains incomplete after the initiating; and
increase at least one of the average threshold or the range threshold from an initial preselected value by a preselected increment when the false positive condition occurs.

11. The device of claim 10 , wherein the controller is configured to
increase the at least one of the average threshold or the range threshold responsive to each of a series of false positive conditions until a preselected upper limit on the at least one of the average threshold or the range threshold is reached.

12. The device of claim 10 , wherein the controller is configured to
increase the at least one of the average threshold or the range threshold responsive to each of a series of false positive conditions until the false positive condition stops occurring.

13. The device of claim 12 , wherein the controller is configured to
reset the at least one of the average threshold or the range threshold to the initial preselected value after a predetermined time has passed since a most recent detection of a change in the capacitance.

14. The device of claim 9 , wherein the controller is configured to:
determine that the vehicle entry process is successful after the process was initiated;
determine a first difference between the determined average and the average threshold corresponding to the successful vehicle entry process;
determine a second difference between the determined range and the range threshold corresponding to the successful vehicle entry process; and
decrease the average threshold by a preselected amount when the first difference is less than the second difference or decrease the range threshold by a preselected amount when the second difference is less than the first difference.

15. The device of claim 9 , wherein
the capacitive vehicle entry control device is associated with a vehicle door handle; and
the controller is configured to

initiate the vehicle entry process based upon determining that an authorized signaling device is near the vehicle door handle prior to unlocking the door,
determine that a user attempted to manipulate the vehicle door handle before the vehicle door was unlocked,
determine a rate of change in the determined plurality of capacitance values preceding the user at

Assignees

• Delphi Tech Inc

Inventors

• Murphy Morgan D
• Hawes Kevin J
• Stark Kris R

Classifications

• B60R25/246

  characterised by the challenge triggering · CPC title

• G07C9/28 Primary

  the pass enabling tracking or indicating presence · CPC title

• E05F15/73

  responsive to movement or presence of persons or objects · CPC title

• E05B81/78

  as part of a hands-free locking or unlocking operation · CPC title

• G07C2009/00769

  with data transmission performed by wireless means · CPC title