SMART BRAKING DEVICES, SYSTEMS, AND METHODS WITH SIGNAL CONDITIONERS

• US 20170082165A1
• Filed: 09/28/2016
• Published: 03/23/2017
• Est. Priority Date: 05/28/2015
• Status: Active Grant

• Current Assignee: ITT Italia SRL (ITT, Inc.)
• Original Assignee: ITT Italia SRL (ITT, Inc.)
• Inventors: Donzelli, Daniele, Solari, Mattia, Terranova, Marco, Serra, Stefano, Martinotto, Luca
• Granted Patent: US 10,208,822 B2
• Time in Patent Office: Days
• CPC Class Codes: F16D 2066/005 Force, torque, stress or strain
• CPC Class Codes: F16D 2066/006 without direct measurement of the quantity monitored, e.g. wear or temperature calculated form force and duration of braking
• CPC Class Codes: F16D 65/092 for axially-engaging brakes, e.g. disc brakes
• CPC Class Codes: F16D 66/00 Arrangements for monitoring working conditions, e.g. wear, temperature
• CPC Class Codes: F16D 66/021 using electrical detection or indication means
• CPC Class Codes: G01L 1/06 by measuring the permanent deformation of gauges, e.g. of compressed bodies
• CPC Class Codes: G01L 1/16 using properties of piezoelectric devices
• CPC Class Codes: G01L 5/28 for testing brakes

Abstract

Various braking devices, systems, and methods are disclosed. In some embodiments, the braking device includes a support element, a block of friction material supported by the support element, at least one piezoceramic sensor supported by the support element and interposed between the block of friction material (and the support element, and a protective element located at the piezoceramic sensor and embedding the latter. The protective element can have one or more layers of resin-based material applied to protect the piezoceramic sensor and direct a predetermined part of the external compression force onto an area of the support element surrounding the piezoceramic sensor. In some embodiments, a signal transduction device is provided and includes at least one piezoceramic sensor supported on a support element and has an integral protective coating having properties of mechanical and temperature resistance.

Claims

1. A sensorized brake pad comprising:

a backplate;

a block of friction material supported by the backplate;

a piezoelectric sensor configured to generate a sensor signal; and

a passive analog front end configured to generate an analog conditioned signal based on conditioning the sensor signal, wherein the analog conditioned signal is substantially proportional to a time derivative of a charge stored in the piezoelectric sensor.

2. The sensorized brake pad of claim 1, further comprising an active analog front end configured to generate an analog output signal based on processing the analog conditioned signal.

3. The sensorized brake pad of claim 2, further comprising a connector, wherein the active analog front end is integrated with the connector.

4. The sensorized brake pad of claim 2, wherein the active analog front end is separated from the passive analog front end by at least about 2 cm.

5. The sensorized brake pad of claim 2, further comprising a transmitter configured to receive the analog output signal and to transmit a wireless signal representing the analog output signal to a control unit that is remote from the sensorized brake pad.

6. The sensorized brake pad of claim 1, further comprising a connector, wherein the passive analog front end is integrated with the connector.

7. The sensorized brake pad of claim 1, wherein the passive analog front end comprises a resistor electrically connected in parallel with the piezoelectric sensor.

8. The sensorized brake pad of claim 1, wherein the passive analog front end comprises a resistor and a capacitor, wherein a first end of the resistor is electrically connected to a first terminal of the piezoelectric sensor via the capacitor, and wherein a second end of the resistor is electrically connected to a second terminal of the piezoelectric sensor.

9. The sensorized brake pad of claim 1, wherein the passive analog front end is integrated with the backplate.

10. The sensorized brake pad of claim 9, wherein the passive analog front end comprises a passive screen printed component on the backplate.

11. The sensorized brake pad of claim 1, wherein the piezoelectric sensor comprises a piezoceramic sensor.

12. A method of generating brake pad data for a vehicle, the method comprising:

generating a sensor signal using a piezoelectric sensor of a brake pad;

generating an analog conditioned signal based on conditioning the sensor signal using a passive analog front end, wherein the analog conditioned signal is substantially proportional to a time derivative of a charge stored in the piezoelectric sensor;

generating an analog output signal based on processing the analog conditioned signal using an active analog front end;

providing the analog output signal to a control unit that is remote from the brake pad; and

processing the analog output signal using the control unit to generate brake pad data.

13. The method of claim 12, wherein processing the analog output signal using the control unit comprises digitizing the analog output signal to generate a digitized signal, integrating the digitized signal to generate an integrated signal, and generating the brake pad data by low frequency noise filtering of the integrated signal.

14. An electrical system for generating brake pad data for a vehicle, wherein the electrical system comprises:

a piezoelectric sensor configured to generate a sensor signal;

a passive analog front end configured to generate an analog conditioned signal based on conditioning the sensor signal;

an active analog front end configured to generate an analog output signal based on processing the analog conditioned signal; and

a control unit configured to process the analog output signal to generate brake pad data, wherein the brake pad data comprises a digital representation of the sensor signal.

15. The electrical system of claim 14, wherein the active analog front end comprises an operational amplifier configured to buffer the analog conditioned signal.

16. The electrical system of claim 14, wherein the passive analog front end comprises a resistor electrically connected in parallel with the piezoelectric sensor.

17. The electrical system of claim 14, wherein the control unit comprises a digitizer configured to generate a digital signal based on digitizing the analog output signal, a digital integration stage configured to generate a digital integrated signal based on integrating the digital signal, and a low frequency noise filtering stage configured to generate the brake pad data based on filtering the digital integrated signal.

18. The electrical system of claim 14, further comprising a cable, wherein the sensorized brake pad comprises a connector, wherein the cable electrically connects the control unit to the sensorized brake pad via the connector.

19. The electrical system of claim 14, further comprising a transmitter configured to receive the analog output signal and to transmit a wireless signal representing the analog output signal to the control unit.

20. The electrical system of claim 14, wherein the analog conditioned signal is substantially proportional to a time derivative of a charge stored in the piezoelectric sensor.