1. A method of determining a belt tension value in a vehicle seat belt exerting a downward force on a seat occupant, comprising the steps:
receiving a plurality of seat belt tension signals representing tensile forces in different locations within a seat belt; and
deriving the belt tension value from the plurality of seat belt tension signals.
2. The method of claim 1 wherein the step of deriving the belt tension value further comprises the steps:
deriving an average seat belt tension value from the plurality of seat belt tension signals; and
deriving the belt tension value from the average seat belt tension value.
3. The method of claim 2 wherein the step of deriving an average seat belt tension value further comprises the steps:
distinguishing invalid ones of the plurality of seat belt tension signals from valid ones of the plurality of seat belt tension signals; and
deriving the average seat belt tension value only from the valid ones of the plurality of seat belt tension signals.
4. The method of claim 3 wherein the step of distinguishing invalid ones of the plurality of seat belt tension signals from valid ones of the plurality of seat belt tension signals comprises, for a selected one of the plurality of seat belt tension signals:
for a predetermined period, deriving a seat belt tension variance measure and a time-averaged seat belt tension value from the selected one of the plurality of seat belt tension signals;
for the predetermined period, deriving a vertical acceleration variance measure and a time-averaged vertical acceleration value from a received signal indicative of expected vertical acceleration of the seat occupant;
deriving a seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a vertical acceleration reference value at least from the time-averaged vertical acceleration value, the seat belt reference value representing a greater proportionate variance from the time-averaged seat belt tension value than a proportionate variance from the time-averaged vertical acceleration value represented by the vertical acceleration reference value; and
determining invalidity of the selected one of the plurality of seat belt tension signals if the seat belt tension signal variance measure exceeds the seat belt tension reference value and the vertical acceleration reference value exceeds the vertical acceleration variance measure.
5. The method of claim 4 wherein the seat belt tension reference value and the vertical acceleration reference value are each derived from both the time-averaged seat belt tension value and the time-averaged vertical acceleration value.
6. The method of claim 4 wherein the seat belt tension variance measure is derived from a sum of absolute values of differences between sampled values of the selected one of the plurality of seat belt tension signals.
7. The method of claim 6 wherein the vertical acceleration measure is derived from a sum of absolute values of differences between sampled values of the received signal indicative of expected vertical acceleration of the seat occupant.
8. The method of claim 4 wherein the step of determining invalidity of the seat belt tension signal is not performed unless the time-averaged seat belt tension value is within a first predetermined range indicating no clipping of the seat belt tension signal during derivation of the seat belt tension variance measure.
9. The method of claim 4 wherein the step of determining invalidity of the seat belt tension signal is not performed unless the time-averaged vertical acceleration value is within a second predetermined range indicating no clipping of the received signal indicative of expected vertical acceleration of the seat occupant during derivation of the vertical acceleration variance measure.
10. The method of claim 4 wherein the seat belt tension reference value of claim 4 is a first seat belt tension reference value and the vertical acceleration value of claim 4 is a first vertical acceleration reference value, the method further comprising the steps:
deriving a second seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a second vertical acceleration reference value at least from the time-averaged vertical acceleration value, the second vertical acceleration reference value representing a proportionate variance from the time-averaged vertical acceleration value greater than a proportionate variance from the time-averaged seat belt tension value represented by the second seat belt tension reference value; and
determining invalidity of the seat belt tension signal if the vertical acceleration variance measure exceeds the second vertical acceleration reference value and the seat belt tension reference measure exceeds the second seat belt tension variance measure.
11. The method of claim 4 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents a weight of an occupant on the seat.
12. The method of claim 11 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents a fluid pressure in a fluid filled bladder disposed in the seat below an occupant thereof.
13. The method of claim 4 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents vertical acceleration of the vehicle seat.
14. Apparatus for determining a belt tension value in a vehicle seat belt exerting a downward force on a seat occupant, comprising:
means for receiving a plurality of seat belt tension signals representing tensile forces in different locations within a seat belt; and
means for deriving the belt tension value from the plurality of seat belt tension signals.
15. The apparatus of claim 14 wherein the means for deriving the belt tension value further comprise:
means for deriving an average seat belt tension value from the plurality of seat belt tension signals; and
means for deriving the belt tension value from the average seat belt tension value.
16. The apparatus of claim 15 wherein the means for deriving an average seat belt tension value further comprise:
means for distinguishing invalid ones of the plurality of seat belt tension signals from valid ones of the plurality of seat belt tension signals; and
means for deriving the average seat belt tension value only from the valid ones of the plurality of seat belt tension signals.
17. The apparatus of claim 16 wherein the means for distinguishing invalid ones of the plurality of seat belt tension signals from valid ones of the plurality of seat belt tension signals comprise:
means for selecting one of the plurality of seat belt tension signals;
means for deriving, for a predetermined period, a seat belt tension variance measure and a time-averaged seat belt tension value from the selected one of the plurality of seat belt tension signals;
means for deriving, for the predetermined period, a vertical acceleration variance measure and a time-averaged vertical acceleration value from a received signal indicative of expected vertical acceleration of the seat occupant;
means for deriving a seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a vertical acceleration reference value at least from the time-averaged vertical acceleration value, the seat belt reference value representing a greater proportionate variance from the time-averaged seat belt tension value than a proportionate variance from the time-averaged vertical acceleration value represented by the vertical acceleration reference value; and
means for determining invalidity of the selected one of the plurality of seat belt tension signals if the seat belt tension signal variance measure exceeds the seat belt tension reference value and the vertical acceleration reference value exceeds the vertical acceleration variance measure.
18. The apparatus of claim 17 wherein the seat belt tension reference value and the vertical acceleration reference value are each derived from both the time-averaged seat belt tension value and the time-averaged vertical acceleration value.
19. The apparatus of claim 17 wherein the seat belt tension variance measure is derived from a sum of absolute values of differences between sampled values of the selected one of the plurality of seat belt tension signals.
20. The apparatus of claim 19 wherein the vertical acceleration measure is derived from a sum of absolute values of differences between sampled values of the received signal indicative of expected vertical acceleration of the seat occupant.
21. The apparatus of claim 17 wherein the means for determining invalidity of the seat belt tension signal do not perform this function unless the time-averaged seat belt tension value is within a first predetermined range indicating no clipping of the seat belt tension signal during derivation of the seat belt tension variance measure.
22. The apparatus of claim 17 wherein the means for determining invalidity of the seat belt tension signal do not perform this function unless the time-averaged vertical acceleration value is within a second predetermined range indicating no clipping of the received signal indicative of expected vertical acceleration of the seat occupant during derivation of the vertical acceleration variance measure.
23. The apparatus of claim 17 wherein the seat belt tension reference value of claim 17 is a first seat belt tension reference value and the vertical acceleration value of claim 17 is a first vertical acceleration reference value, the apparatus further comprising:
means for deriving a second seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a second vertical acceleration reference value at least from the time-averaged vertical acceleration value, the second vertical acceleration reference value representing a proportionate variance from the time-averaged vertical acceleration value greater than a proportionate variance from the time-averaged seat belt tension value represented by the second seat belt tension reference value; and
means for determining invalidity of the seat belt tension signal if the vertical acceleration variance measure exceeds the second vertical acceleration reference value and the seat belt tension reference measure exceeds the second seat belt tension variance measure.
24. The apparatus of claim 17 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents a weight of an occupant on the seat.
25. The method of claim 24 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents a fluid pressure in a fluid filled bladder disposed in the seat below an occupant thereof.
26. The method of claim 17 wherein the received signal indicative of expected vertical acceleration of the seat occupant represents vertical acceleration of the vehicle seat.
27. Apparatus for characterizing an occupant of a vehicle seat, the apparatus comprising:
a seat belt disposed in association with the vehicle seat for restraint of the occupant;
a plurality of belt tension sensors providing seat belt tension signals at different points of the seat belt;
a weight sensor disposed on the vehicle seat and responsive to the downward force exerted by the seat occupant as well as a downward force exerted by tension in the vehicle seat belt through the vehicle occupant; forces in different locations within the seat belt; and
means for deriving a belt tension value from the plurality of seat belt tension signals; and
means for characterizing the occupant responsive to a signal from the weight sensor and the belt tension value.
28. The apparatus of claim 27 wherein the means for deriving the belt tension value further comprise:
means for deriving an average seat belt tension value from the seat belt tension signals; and
means for deriving the belt tension value from the average seat belt tension value.
29. The apparatus of claim 28 wherein the means for deriving an average seat belt tension value further comprise:
means for distinguishing invalid ones of the seat belt tension signals from valid ones of the seat belt tension signals; and
means for deriving the average seat belt tension value only from the valid ones of the seat belt tension signals.
30. The apparatus of claim 29 wherein the means for distinguishing invalid ones of the seat belt tension signals from valid ones of the seat belt tension signals comprise:
means for selecting one of the seat belt tension signals;
means for deriving, for a predetermined period, a seat belt tension variance measure and a time-averaged seat belt tension value from the selected one of the seat belt tension signals;
means for deriving, for the predetermined period, a vertical acceleration variance measure and a time-averaged vertical acceleration value from a received signal indicative of expected vertical acceleration of the seat occupant;
means for deriving a seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a vertical acceleration reference value at least from the time-averaged vertical acceleration value, the seat belt reference value representing a greater proportionate variance from the time-averaged seat belt tension value than a proportionate variance from the time-averaged vertical acceleration value represented by the vertical acceleration reference value; and
means for determining invalidity of the selected one of the plurality of seat belt tension signals if the seat belt tension signal variance measure exceeds the seat belt tension reference value and the vertical acceleration reference value exceeds the vertical acceleration variance measure.
31. The apparatus of claim 30 wherein the seat belt tension reference value and the vertical acceleration reference value are each derived from both the time-averaged seat belt tension value and the time-averaged vertical acceleration value.
32. The apparatus of claim 30 wherein the seat belt tension variance measure is derived from a sum of absolute values of differences between sampled values of the selected one of the seat belt tension signals.
33. The apparatus of claim 32 wherein the vertical acceleration measure is derived from a sum of absolute values of differences between sampled values of the received signal indicative of expected vertical acceleration of the seat occupant.
34. The apparatus of claim 30 wherein the seat belt tension reference value of claim 17 is a first seat belt tension reference value and the vertical acceleration value of claim 17 is a first vertical acceleration reference value, the apparatus further comprising:
means for deriving a second seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a second vertical acceleration reference value at least from the time-averaged vertical acceleration value, the second vertical acceleration reference value representing a proportionate variance from the time-averaged vertical acceleration value greater than a proportionate variance from the time-averaged seat belt tension value represented by the second seat belt tension reference value; and
means for determining invalidity of the seat belt tension signal if the vertical acceleration variance measure exceeds the second vertical acceleration reference value and the seat belt tension reference measure exceeds the second seat belt tension variance measure.
35. The apparatus of claim 30 wherein the occupant weight sensor provides the received signal indicative of expected vertical acceleration of the seat occupant.
36. The apparatus of claim 35 wherein the occupant weight sensor comprises a fluid filled bladder disposed in the seat below an occupant thereof and the received signal indicative of expected vertical acceleration of the seat occupant indicates a fluid pressure in the fluid filled bladder.
37. The apparatus of claim 30 wherein an accelerometer fixed with respect to the vehicle seat provides the received signal indicative of expected vertical acceleration of the seat occupant.
38. A method of determining tension in a vehicle seat belt comprising the steps:
providing a plurality of seat belt tension sensors distributed at different locations along the seat belt;
reading tension signals from the plurality of seat belt tension sensors;
calculating an average tension signal from ones of the tension signals presumed to be valid;
identifying an outlier one of the tension signals outside a calibrated tolerance band around the average tension signal;
testing the identified outlier one of the tension signals for valid dynamic variance during vehicle motion;
if the outlier one of the tension signals fails the test, recalculating the average tension signal without the identified outlier one of the tension signals;
repeating the identifying, testing and recalculating steps until all outlier ones of the tension signals failing the test are eliminated and a final recalculated average tension signal is obtained; and
providing the final recalculated average tension signal as the determined tension in the vehicle seat belt.
39. The method of claim 38 wherein the step of testing the identified outlier one of the tension signals for valid dynamic variance during vehicle motion comprises the following steps:
for a predetermined period, deriving a seat belt tension variance measure and a time-averaged seat belt tension value from the identified outlier one of the plurality of seat belt tension signals;
for the predetermined period, deriving a vertical acceleration variance measure and a time-averaged vertical acceleration value from a received signal indicative of expected vertical acceleration of an occupant restrained by the seat belt;
deriving a seat belt tension reference value at least from the time-averaged seat belt tension value and deriving a vertical acceleration reference value at least from the time-averaged vertical acceleration value, the seat belt reference value representing a greater proportionate variance from the time-averaged seat belt tension value than a proportionate variance from the time-averaged vertical acceleration value represented by the vertical acceleration reference value; and
declaring failure of the test if the seat belt tension signal variance measure exceeds the seat belt tension reference value and the vertical acceleration reference value exceeds the vertical acceleration variance measure.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A soft toy comprising:
a soft toy body;
a pressure sensing logic internal to the soft toy body configured to measure a pressure exerted on the soft toy body;
at least one output device; and
control logic configured to generate at least one output at the at least one output device when the pressure sensing logic measures that a pressure exerted on the soft toy body is within a predetermined pressure range.
2. The soft toy of claim 1 further comprising:
a spring, and wherein the pressure sensing logic is configured to measure the pressure exerted on the soft boy toy based, at least in part, a compression of the spring.
3. The soft toy of claim 1 further comprising:
an air bladder inside the soft toy body, and wherein the pressure sensing logic is configured to measure a pressure of air in the air bladder.
4. The soft toy of claim 3 wherein the pressure sensing logic is configured to be activated by air movement from the air bladder into the pressure sensing logic.
5. The soft toy of claim 1 wherein the at least one output device further comprises:
a display configured to display images.
6. The soft toy of claim 5 wherein the soft toy body further comprises:
flexible fabric forming an outside surface of the soft toy body, wherein the display is configured to be mounted in an opening in the flexible fabric.
7. The soft toy of claim 5 wherein the display further comprises:
a display screen in a same plain of flexible fabric surrounding the display screen.
8. The soft toy of claim 5 wherein the display is a liquid crystal display (LCD).
9. The soft toy of claim 5 wherein the display is further configured to display at least one of the group of: graphical images and text messages
10. The soft toy of claim 1 further comprising:
a battery internal inside the soft toy body configured to power the control logic and the pressure sensing logic.
11. The soft toy of claim 1 wherein the at least on output device further comprises:
a speaker configured to generate sounds.
12. The soft toy of claim 10 further comprising:
a speaker, wherein the control logic is configured activate the speaker to generate sounds proportional to pressure measured by the pressure sensing logic.
13. The soft toy of claim 1 wherein the soft toy is sized to be squeezed by at least one of the group of: one human hand, two human hands, one human arm, two human arms, a combination of a human hand and a human body, and a combination of a human arm and a human body.
14. A method for generating outputs at a soft toy comprising:
measuring a toy pressure within the soft toy;
determining if the pressure exceeds a threshold pressure;
when the toy pressure exceeds the threshold pressure, generating at least one output from the soft toy.
15. The method for generating outputs at a soft toy of claim 14 wherein the measuring further comprises:
measuring the toy pressure within an air bladder that is located inside the soft toy.
16. The method for generating outputs at a soft toy of claim 14 wherein the measuring further comprises:
measuring the pressure using an electronic measuring sensor located inside the soft toy
17. The method for generating outputs at a soft toy of claim 14 where the air pressure is a first pressure, the threshold pressure is a first threshold pressure and the at least one output is a first output and further comprising:
measuring a second pressure within the soft toy;
determining if the second pressure exceeds a second threshold pressure; and
when the second pressure exceeds the second threshold pressure, generating at least one second output from the soft toy that is different than the first output.
18. The method for generating outputs at a soft toy of claim 14 further comprising
waiting a predetermined amount of time; and
turning off the at least one output after the predetermined time.
19. The method for generating outputs at a soft toy of claim 14 further comprising
when no change in pressure has been detected for a timer period, placing electronic components in the soft toy in a sleep state to save power.
20. The method for generating outputs at a soft toy of claim 14 further comprising at least one of the group of:
generating an image on a display of the soft toy and generating sounds on a speaker of the soft toy.