Child seat detection system

• US 6,678,600 B2
• Filed: 12/04/2002
• Issued: 01/13/2004
• Est. Priority Date: 12/04/2001
• Status: Expired due to Term

• Current Assignee: Appy Risk Technologies Limited (Trak Global Group Ltd.)
• Original Assignee: Intelligent Mechatronic Systems Inc. (Trak Global Group Ltd.)
• Inventors: Gueaieb, Wail, Johnson, Brian, Basir, Otman A., Karray, Fakhreddine
• Primary Examiner(s): Camby, Richard M.
• Application Number:
  US10/310,119
• Publication Number:
  US 20030105570A1
• Time in Patent Office: 405 Days
• Field of Search: 280/734, 280/735, 180/272, 342/70, 342/72, 701/45, 701/49
• US Class Current: 701/45
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: B60R 21/01556 Child-seat detection systems

Abstract

A child seat detection system determines the presence of an infant seat and can distinguish between a forward-facing infant seat and a rearward-facing infant seat. The system determines the weight on a vehicle seat and compares the weight on the vehicle seat to a rear-facing infant seat maximum. If the weight on the vehicle seat exceeds the rear-facing infant seat maximum, the system determines whether a forward-facing infant seat is on the seat. If the weight on the vehicle seat does not exceed the rear-facing infant seat maximum, then the system determines whether a rear-facing infant seat is on the seat.

Claims

1. A method for detecting a child seat in a vehicle including the steps of:

a) determining weight on a vehicle seat;

b) comparing the weight on the vehicle seat to a rear-facing infant seat maximum;

c) if the weight on the vehicle seat exceeds the rear-facing infant seat maximum, determining whether a forward-facing infant seat is on the seat;

d) if the weight on the vehicle seat does not exceed the rear-facing infant seat maximum, determining whether a rear-facing infant seat is on the seat.

2. The method of claim 1 further including the steps of:

determining that the seat is empty if the weight on the vehicle seat does not exceed an empty threshold and performing said steps b)-d) only if the weight on the seat exceeds the empty threshold.

3. The method of claim 1 further including the steps of:

determining whether a seatbelt for the vehicle seat is in use and using a belted rear-facing infant seat maximum if the seatbelt is in use and using an unbelted rear-facing infant seat maximum if the seatbelt is not in use, the unbelted rear-facing infant seat maximum less than the belted rear-facing infant seat maximum.

4. The method of claim 1 further including the steps of:

determining a proximity gain of an occupant on the vehicle seat relative to a sensor in the vehicle headliner; and

determining that an infant seat is present based upon the proximity gain.

5. The method of claim 1 further including the steps of:

measuring capacitance from a seat back sensor; and

determining that an infant seat is present based upon the measured capacitance.

6. The method of claim 1 further including the steps of:

measuring weight on a front portion of the vehicle seat; and

determining that an infant seat is present based upon the measured weight on the front portion.

7. A method for detecting a child seat in a vehicle including the steps of:

a) determining a seat weight on a vehicle seat;

b) determining a proximity gain of an occupant on the vehicle seat relative to a sensor in the vehicle headliner;

c) determining that the seat is empty if the seat weight does not exceed an empty threshold;

d) comparing the seat weight to a rear-facing infant seat maximum greater than the empty threshold;

e) if the seat weight exceeds the rear-facing infant seat maximum, determining whether a forward-facing infant seat is on the seat by comparing the seat weight to a forward-facing infant seat maximum and by comparing the proximity gain to a forward-facing infant seat proximity gain threshold; and

f) if the seat is not empty and if the seat weight does not exceed the rear-facing infant seat maximum, determining whether a rear-facing infant seat is on the seat by comparing the proximity gain to a rear-facing infant seat gain threshold.

8. The method of claim 7 further including the steps of:

determining whether a seatbelt for the vehicle seat is in use, wherein the rear-facing infant seat maximum is a belted rear-facing infant seat maximum if the seatbelt is in use and an unbelted rear-facing infant seat maximum if the seatbelt is not in use, the unbelted rear-facing infant seat maximum less than the belted rear-facing infant seat maximum.

9. The method of claim 8 wherein the forward-facing infant seat maximum is a belted forward-facing infant seat maximum if the seatbelt is in use and an unbelted forward-facing infant seat maximum if the seatbelt is not in use, the unbelted forward-facing infant seat maximum less than the belted forward-facing infant seat maximum.

10. The method of claim 9 further including the steps of:

measuring capacitance from a seat back; and

determining that a forward-facing infant seat is present only if the measured capacitance is less than a threshold value.

11. The method of claim 10 further including the steps of:

measuring weight on a front portion of the vehicle seat; and

determining that a forward-facing infant seat is present only if the measured weight on the front portion is less than a front weight threshold.

12. A computer-readable medium storing a computer program which when executed by a computer performs the steps of:

a) determining that a vehicle seat is empty if a seat weight does not exceed an empty threshold;

b) comparing the seat weight to a rear-facing infant seat maximum greater than the empty threshold;

c) if the seat weight exceeds the rear-facing infant seat maximum, determining whether a forward-facing infant seat is on the seat by comparing the seat weight to a forward-facing infant seat maximum and by comparing a proximity gain relative to an overhead sensor to a forward-facing infant seat proximity gain threshold;

d) if the seat is not empty and if the seat weight does not exceed the rear-facing infant seat maximum, determining whether a rear-facing infant seat is on the seat by comparing the proximity gain to a rear-facing infant seat gain threshold.

13. A child seat detection system comprising:

a weight sensor for measuring seat weight on a vehicle seat; and

a controller comparing the seat weight to a rear-facing infant seat maximum and determining whether a forward-facing infant seat is on the seat if the weight on the vehicle seat exceeds the rear-facing infant seat maximum, and determining whether a rear-facing infant seat is on the seat if the weight on the vehicle seat does not exceed the rear-facing infant seat maximum.

14. The child seat detection system of claim 13 further comprising:

a sensor determining a height of the occupant;

the controller determining that a rear-facing infant seat is present only if the height exceeds a rear-facing infant seat height threshold.

15. The child seat detection system of claim 14 wherein the controller determines that a forward-facing infant seat is present only if the height exceeds a forward-facing infant seat height threshold.

16. The child seat detection system of claim 15 further comprising:

a capacitance sensor in a seat back; and

the controller determining that a forward-facing infant seat is present only if the capacitance measured by the capacitance sensor is less than a threshold value.

17. The child seat detection system of claim 16 wherein the weight sensor includes a front weight sensor measuring a front weight on a front portion of the seat independent of a rear portion of the seat, the controller determining that a forward-facing infant seat is present only if the front weight is less than a front weight threshold.