SENSOR SYSTEMS INTEGRATED WITH VEHICLE TIRES

• US 20160318356A1
• Filed: 04/26/2016
• Published: 11/03/2016
• Est. Priority Date: 04/30/2015
• Status: Active Grant

• Current Assignee: BeBop Sensors, Inc.
• Original Assignee: BeBop Sensors, Inc.
• Inventors: McMillen, Keith A.
• Granted Patent: US 10,082,381 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60C 11/243 Tread wear sensors, e.g. electronic sensors
• CPC Class Codes: B60C 2019/004 Tyre sensors other than for detecting tyre pressure
• CPC Class Codes: B60C 23/064 comprising tyre mounted deformation sensors, e.g. to determine road contact area
• CPC Class Codes: B60T 2210/36 Global Positioning System [GPS]
• CPC Class Codes: B60T 2240/03 Tire sensors
• CPC Class Codes: B60T 8/1725 Using tyre sensors, e.g. Sidewall Torsion sensors [SWT] for tyre pressure and temperature detection B60C23/00
• CPC Class Codes: G01B 7/06 for measuring thickness measuring during the manufacture of coatings C23C14/54
• CPC Class Codes: G01B 7/22 using change in capacitance
• CPC Class Codes: G01L 1/18 using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
• CPC Class Codes: G01L 1/2287 constructional details of the strain gauges adjustable resistors H01C10/00
• CPC Class Codes: G01L 17/005 using a sensor contacting the exterior surface, e.g. for measuring deformation
• CPC Class Codes: G01L 9/0002 using variations in ohmic resistance G01L9/0051 takes precedence

Abstract

Sensor systems using piezoresistive materials are described that may be integrated with vehicle tires for use in a variety applications such as, for example, tire pressure monitoring, tread wear monitoring, anti-lock braking system control, suspension adjustment and/or control, wheel-drive system control, or road surface determination.

Claims

1. A sensor system for use with a vehicle tire, comprising:

a flexible piezoresistive substrate; and

an array of sensors, each sensor including at least two conductive traces formed directly on the piezoresistive substrate, each sensor being positioned on the substrate to align with a region of the vehicle tire, wherein resistance between the conductive traces varies with force applied to the piezoresistive substrate; and

sensor circuitry configured to receive sensor signals from the array of sensors, each sensor signal representing a force associated with a corresponding one of the sensors;

wherein the sensor system is configured to conform to an interior of the vehicle tire.

2. The sensor system of claim 1, wherein the sensor circuitry is further configured to selectively energize the sensors to generate the sensor signals.

3. The sensor system of claim 1, wherein the sensor circuitry is disposed on a printed circuit board that is integrated with the piezoresistive substrate.

4. The sensor system of claim 1, wherein the sensor circuitry is further configured to process the sensor signals corresponding to multiple sensors in the array of sensors to determine a speed and direction of the force.

5. The sensor system of claim 1, wherein the piezoresistive substrate is a piezoresistive fabric.

6. The sensor system of claim 5, wherein the piezoresistive fabric is woven or non-woven.

7. The sensor system of claim 1, wherein the piezoresistive substrate is a piezoresistive rubber.

8. The sensor system of claim 1, wherein the conductive traces comprise conductive ink printed on the piezoresistive substrate.

9. The sensor system of claim 8, wherein the conductive ink comprises a silicone ink having conductive particles suspended therein.

10. The sensor system of claim 1, wherein the conductive traces comprise conductive paint deposited on the piezoresistive substrate.

11. The sensor system of claim 1, wherein the sensor circuitry is configured to generate control information from the sensor signals, the control information being for use by a tire pressure monitoring system, a tread wear monitoring system, an anti-lock braking system, a suspension adjustment and/or control system, a wheel-drive system, or a road surface determination system.

12. A vehicle tire including the sensor system of claim 1.

13. The vehicle tire of claim 12, wherein the vehicle tire comprises a plurality of layers, a first one of the layers including the piezoresistive substrate and sensor array.

14. The vehicle tire of claim 12, further comprising a mounting platform integrated with an inner surface of the tire during vulcanization of the tire, the sensor system being mounted on the mounting platform after vulcanization of the tire.

15. A sensor system for use with a vehicle tire, comprising:

piezoresistive material;

a dielectric substrate aligned and in contact with the piezoresistive material; and

an array of sensors, each sensor including at least two conductive traces formed directly on the dielectric substrate such that the conductive traces are in contact with the piezoresistive material, each sensor being positioned on the dielectric substrate to align with a region of the vehicle tire, wherein resistance between the conductive traces varies with force applied to the piezoresistive material; and

sensor circuitry configured to receive sensor signals from the array of sensors, each sensor signal representing a force associated with a corresponding one of the sensors;

wherein the sensor system is configured to conform to an interior of the vehicle tire.

16. The sensor system of claim 15, wherein the piezoresistive material is a continuous flexible substrate.

17. The sensor system of claim 15, wherein the piezoresistive material is a plurality of patches of piezoresistive material, each patch of the piezoresistive material being aligned with one or more of the sensors.

18. A method for determining locations of each of a plurality of tires on a vehicle, comprising:

receiving turn data representing a plurality of right and left turns of the vehicle;

receiving tire sensor data for each of the tires of the vehicle, the tire sensor data representing forces at a contact patch for the corresponding tire; and

determining a tire location on the vehicle for each of the tires with reference to the turn data and the tire sensor data.

19. The method of claim 18, wherein the turn data comprises global positioning system (GPS) data representing directions of travel for the vehicle.

20. The method of claim 18, wherein determining the tire location for each of the tires includes correlating first portions of the tire sensor data for each of the tires with one or more turns represented in the turn data, and comparing the first portions of the tire sensor data for a first subset of the tires to determine which of the first subset of tires are on a left side of the vehicle and which of the first subset of tires are on a right side of the vehicle.

21. The method of claim 20, wherein the first portions of the tire sensor data for each of the tires represent a slip angle for the corresponding tire, and wherein comparing the first portions of the tire sensor data for the first subset of tires includes comparing the slip angles for the first subset of tires.

22. The method of claim 20, wherein the first portions of the tire sensor data for each of the tires represent at least some of the forces at the contact patch for the corresponding tire, and wherein comparing the first portions of the tire sensor data for the first subset of tires includes comparing the forces represented in the first portions of the tire sensor data.

23. The method of claim 20, further comprising comparing the first portions of the tire sensor data for a second subset of the tires to determine which of the second subset of tires are front tires and which of the second subset of tires are rear tires.

24. The method of claim 23, wherein the first portions of the tire sensor data for each of the tires represent a slip angle for the corresponding tire, and wherein comparing the first portions of the tire sensor data for the second subset of tires includes comparing the slip angles for the second subset of tires.

25. The method of claim 23, wherein the first portions of the tire sensor data for each of the tires represent at least some of the forces at the contact patch for the corresponding tire, and wherein comparing the first portions of the tire sensor data for the second subset of tires includes comparing the forces represented in the first portions of the tire sensor data.

26. The method of claim 20, wherein determining the tire location for each of the tires includes correlating second portions of the tire sensor data for each of the tires with one or more acceleration events, and comparing the second portions of the tire sensor data for a second subset of the tires to determine which of the second subset of tires are front tires and which of the second subset of tires are rear tires.

27. The method of claim 18, further comprising comparing accelerometer data from each of the tires to determine an ordering of the tires from a front to a back of the vehicle.

28. The method of claim 18, further comprising associating the tire sensor data with the corresponding tire with reference to a device identifier associated with a tire sensor system integrated with the corresponding tire.

29. The method of claim 18, wherein determining the tire location for each of the tires includes correlating first portions of the tire sensor data for each of the tires with one or more acceleration events, and comparing the first portions of the tire sensor data for a first subset of the tires to determine which of the first subset of tires are front tires and which of the first subset of tires are rear tires.

30. The method of claim 29, further comprising correlating rotational speeds of the tires with one or more turns represented in the turn data, and comparing the rotational speeds of a second subset of the tires for one or more of the turns to determine which of the second subset of tires are on a left side of the vehicle and which of the second subset of tires are on a right side of the vehicle.

31. The method of claim 18, wherein at least some of the tires of the vehicle are arranged as pairs on a same axle and on a same side of the vehicle, each pair of tires having an inside tire and an outside tire, and wherein determining the tire location for each of the tires includes comparing apparent directions of rotation of the tires in each pair of tires to determine which of the tires in each pair of tires is the inside tire and which is the outside tire.