# US 11,441,629 B2 · Residual braking torque indication devices, systems, and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,441,629 B2 - Document ID: US11441629B2 - Status: Granted - Kind: B2 - Application number: 16/584,429 - Filed: 2019-09-26 - Published: 2020-03-19 - Granted: 2022-09-13 - Earliest claimed: 2016-07-25 - Assignees: ITT Italia S.r.l. - Applicants: ITT ITALIA S.r.l. - Inventors: Mattia Solari; Marco Terranova - Web page: https://patentgrep.com/patent/US11441629B2 ## CPC - F16D 66/021: {using electrical detection or indication means} - B60T 17/22: Devices for monitoring or checking brake systems; Signal devices - B60T 17/221: {Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems (hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M)} - F16D 65/08: for internally-engaging brakes - B60T 2201/12: Pre-actuation of braking systems without significant braking effect; Optimizing brake performance by reduction of play between brake pads and brake disc - F16D 2066/001: {Temperature} - F16D 2066/005: {Force, torque, stress or strain} - F16D 2066/006: {without direct measurement of the quantity monitored, e.g. wear or temperature calculated form force and duration of braking} - F16D 2121/28: using electrostrictive or magnetostrictive elements, e.g. piezoelectric elements - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES ## Abstract Various residual braking torque indication devices, systems, and methods are described. The devices, systems, and methods can include a sensorized brake pad. An output signal of the sensorized brake pad can be processed to provide an indication of a residual braking torque. The residual braking torque indicator can be calibrated to reference data to provide an actual measurement of the residual braking torque. ## Claims ### Claim 1 A device for measuring residual braking torque applied by a brake pad to a brake rotor of a vehicle, the device comprising: a force sensor positioned on the brake pad, the force sensor configured to output signals indicating at least one of shear force and pressure applied by the brake pad to the brake rotor; and an electrical circuit connecting the force sensor to an electronic control unit, the electronic control unit configured to receive the signals from the force sensor, wherein the electronic control unit is configured to: perform at least one of frequency domain and time domain analysis of the signals from the force sensor to determine a residual braking torque indicator that indirectly indicates the residual braking torque applied by the brake pad to the brake rotor, without direct measurement of the residual braking torque, wherein the determination of the residual braking torque indicator includes detection of a structure of oscillations of the intensity of the signals over time, wherein the oscillations are associated with an angular velocity of rotation of a wheel of the vehicle; and convert the residual braking torque indicator to a measurement of residual braking torque applied by the brake pad to the brake rotor using a calibration comprising a relationship between the residual torque indicator and residual braking torque. ### Claim 2 (depends on 1) The device according to claim 1, wherein the measurements of residual braking torque are from 0.1 Nm to 30 Nm. ### Claim 3 (depends on 1) The device according to claim 1, wherein the electronic control unit is configured to perform an analysis based on at least one of frequency and time. ### Claim 4 (depends on 1) The device according to claim 1, wherein the electronic control unit is configured to determine the residual braking torque based on the frequency spectrum of the signals provided by the force sensor. ### Claim 5 A device for measuring residual braking torque applied by a brake pad of a vehicle, the device comprising: a force sensor positioned on the brake pad, the force sensor configured to output signals indicating at least one of shear force and pressure applied by the brake pad; and an electrical circuit connecting the force sensor to an electronic control unit, the electronic control unit configured to receive the signals from the force sensor, wherein the electronic control unit is configured to: perform a frequency domain analysis of the signals from the force sensor to determine a residual braking torque indicator that indirectly indicates the residual braking torque applied by the brake pad, without direct measurement of the residual braking torque, wherein the determination of the residual braking torque indicator includes detection of a specific peak structure within a frequency spectrum of the signals, wherein the specific peak structure is associated with an angular velocity of rotation of a wheel of the vehicle that indirectly indicates the residual braking torque applied by the brake pad; and convert the residual braking torque indicator to a measurement of the residual braking torque applied by the brake pad using a calibration comprising a relationship between the residual torque indicator and residual braking torque. ### Claim 6 A device for measuring residual braking torque applied by a brake pad of a vehicle, the device comprising: a force sensor positioned on the brake pad, the force sensor configured to output signals indicating at least one of shear force and pressure applied by the brake pad; a band-pass filter operating at around 50 Hz; and an electrical circuit connecting the force sensor to an electronic control unit, the electronic control unit configured to receive the signals from the force sensor, wherein the electronic control unit is configured to: perform at least one of frequency domain and time domain analysis of the signals from the force sensor to determine a residual braking torque indicator that indirectly indicates the residual braking torque applied by the brake pad, without direct measurement of the residual braking torque; convert the residual braking torque indicator to a measurement of the residual braking torque applied by the brake pad using a calibration comprising a relationship between the residual torque indicator and residual braking torque. ### Claim 7 (depends on 1) The device according to claim 1, wherein the electronic control unit further comprises at least one friction material wear indicator. ### Claim 8 (depends on 1) The device according to claim 1, wherein a connector is integrated into the brake pad, and the connector is connected to the electrical circuit and the electronic control unit via an electric cable. ### Claim 9 (depends on 1) The device according to claim 1, wherein a connector is integrated into the brake pad, and the connector is connected to the electrical circuit by integrating a wireless data transmission module in order to communicate with at least one vehicle on board computer via at least one dedicated communication system. ### Claim 10 (depends on 1) The device according to claim 1, wherein the electronic control system is further configured to activate an alarm in response to the residual braking torque on the wheel exceeding a threshold value. ### Claim 11 (depends on 1) The device according to claim 1, wherein the force sensor comprises a piezoceramic sensor. ### Claim 12 (depends on 1) The device according to claim 1, wherein the residual braking torque is determined based on empirical test data of measured residual braking torque. ### Claim 13 (depends on 5) The device according to claim 5, wherein the residual braking torque is determined based on empirical test data of measured residual braking torque. ### Claim 14 (depends on 6) The device according to claim 6, wherein the residual braking torque is determined based on empirical test data of measured residual braking torque. ### Claim 15 (depends on 5) The device according to claim 5, wherein the electronic control system is further configured to activate an alarm in response to the residual braking torque on the wheel exceeding a threshold value. ### Claim 16 (depends on 5) The device according to claim 5, wherein the electronic control unit further comprises at least one friction material wear indicator. ### Claim 17 (depends on 6) The device according to claim 6, wherein the electronic control unit further comprises at least one friction material wear indicator. ### Claim 18 (depends on 5) The device according to claim 5, wherein a connector is integrated into the brake pad, and the connector is connected to the electrical circuit and the electronic control unit via an electric cable. ### Claim 19 (depends on 6) The device according to claim 6, wherein a connector is integrated into the brake pad, and the connector is connected to the electrical circuit and the electronic control unit via an electric cable. ### Claim 20 (depends on 5) The device according to claim 5, wherein a connector is integrated into the brake pad, and the connector is connected to the electrical circuit by integrating a wireless data transmission module in order to communicate with at least one vehicle on board computer via at least one dedicated communication system.