# US 10,766,494 B2 · Road surface characterization based upon filter coefficients > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,766,494 B2 - Document ID: US10766494B2 - Status: Granted - Kind: B2 - Application number: 15/932,267 - Filed: 2018-02-16 - Published: 2019-08-22 - Granted: 2020-09-08 - Earliest claimed: 2018-02-16 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Timothy J. Roggenkamp; Christopher A. Stirlen; Frank C. Valeri - Web page: https://patentgrep.com/patent/US10766494B2 ## CPC - B60W 40/06: Road conditions - B60W 40/068: Road friction coefficient - B60W 40/10: related to vehicle motion - B60W 40/105: Speed - B60W 10/04: including control of propulsion units - B60W 2050/0052: {Filtering, filters} - B60W 2050/0059: {Signal noise suppression} - B60W 2400/00: Indexing codes relating to detected, measured or calculated conditions or factors - B60W 2420/54: Audio sensitive means, e.g. ultrasound - B60W 2552/35: Road bumpiness, e.g. potholes - B60W 2710/10: Change speed gearings - B60W 2710/18: Braking system - B60W 2710/20: Steering systems - B60W 2710/30: Auxiliary equipments - B60W 2720/10: Longitudinal speed - B60W 2900/00: Indexing codes relating to the purpose of, or problem solved of road vehicle drive control systems not otherwise provided for in groups B60W30/00 - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT ## Abstract A system that determines a road surface profile based upon filter coefficient data from noise cancellation systems is disclosed. The system includes a filter coefficient monitoring module that is configured to receive a first set of filter coefficient data from an noise cancellation module. The system also includes a road surface profile module that is configured to receive an input representing a road surface type and generate a road surface profile based upon the road surface type and the first set of filter coefficient data and to store the road surface profile including a correspondence between the road surface type and the first set of filter coefficient data. ## Claims ### Claim 1 A road profile detection system for a vehicle, comprising: a noise cancellation module including a plurality of taps with a plurality of filter coefficients, respectively and configured to adjust values of the plurality of filter coefficients during operation of the vehicle; a filter coefficient monitoring module configured to sample the plurality of filter coefficients from the noise cancellation module; and a road surface determination module configured to receive the plurality of filter coefficients and to determine a road surface type based on the plurality of filter coefficients. ### Claim 2 (depends on 1) The road profile detection system as recited in claim 1, wherein the road surface determination module is further configured to: compare the plurality of filter coefficients to filter coefficients of a plurality of stored entries; and in response to the plurality of filter coefficients corresponding to one of the plurality of stored entries, select a road surface type corresponding to the one of the plurality of stored entries. ### Claim 3 (depends on 2) The road profile detection system as recited in claim 2, further comprising a look-up table including the plurality of stored entries. ### Claim 4 (depends on 1) The road profile detection system as recited in claim 1, further comprising a control module configured to modify an operating parameter of a vehicle based upon the road surface type as determined by the road surface determination module. ### Claim 5 (depends on 4) The road profile detection system as recited in claim 4, wherein the operating parameter comprises at least one of applying a brake, adjusting a body mount, and adjusting an active filter associated with the noise cancellation module. ### Claim 6 (depends on 1) The road profile detection system as recited in claim 1, wherein the noise cancellation module is further configured to adjust values of the plurality of filter coefficients during operation of the vehicle based on outputs of at least one vibration sensor of the vehicle and at least one microphone in the vehicle. ### Claim 7 A system, comprising: a filter coefficient monitoring module that is configured to receive a first set of filter coefficient data from a noise cancellation module; a road surface profile module that is configured to: receive an input representing a road surface type and generate a road surface profile based upon the road surface type and the first set of filter coefficient data; store the road surface profile including a correspondence between the road surface type and the first set of filter coefficient data; and perform a matrix calculation on the first set of filter coefficient data to represent the road surface profile; and a road surface determination module that is configured to: receive a second set of filter coefficient data and determine the road surface type based upon the second set of filter coefficient data, the second set of filter coefficient data different from the first set of filter coefficient data; and access a look-up table, provide the second set of filter coefficient data to the look-up table, and receive the road surface type from the look-up table. ### Claim 8 A method, comprising: receiving a second set of filter coefficient data; retrieving a road surface profile based upon the second set of filter coefficient data, the road surface profile including a road surface type that corresponds to a first set of filter coefficient data; determining the road surface type based upon the second set of filter coefficient data, the second set of filter coefficient data different from the first set of filter coefficient data; accessing a look-up table, providing the second set of filter coefficient data to the look-up table, and receiving the road surface type from the look-up table; and performing a matrix calculation on the first set of filter coefficient data to represent the road surface profile. ### Claim 9 A method for detecting a road profile in a vehicle, comprising: performing noise cancellation using a plurality of taps with a plurality of filter coefficients, respectively; adjusting values of the plurality of filter coefficients during operation of the vehicle; and determining a road surface type based on the plurality of filter coefficients. ### Claim 10 (depends on 9) The method as recited in claim 9, wherein determining the road surface type includes: comparing the plurality of filter coefficients to filter coefficients of a plurality of stored entries; determining that the plurality of filter coefficients corresponds to one of the plurality of stored entries; and selecting a road surface type corresponding to the one of the plurality of stored entries. ### Claim 11 (depends on 9) The method as recited in claim 9, further comprising modifying an operating parameter of a vehicle based upon the road surface type. ### Claim 12 (depends on 11) The method as recited in claim 11, wherein the operating parameter at least one of controls a brake, controls a body mount, and adjusts an active filter associated with noise cancellation. ### Claim 13 (depends on 9) The method as recited in claim 9, further comprising adjusting values of the plurality of filter coefficients during operation of the vehicle based on outputs of at least one vibration sensor of the vehicle and at least one microphone in the vehicle.