Use of participative sensing systems to enable enhanced road friction estimation

Patent metadata

Field	Value
Publication number	US-9475500-B2
Application number	US-201414539803-A
Country	US
Kind code	B2
Filing date	Nov 12, 2014
Priority date	Nov 12, 2014
Publication date	Oct 25, 2016
Grant date	Oct 25, 2016

Abstract

Methods and systems are disclosed for participative sensing of road friction conditions by vehicles, collection of the friction data from a large number of vehicles by a central server, processing the data to classify friction conditions by roadway and locale, and sending notifications of the friction conditions to vehicles as appropriate. A large number of vehicles use participative sensing systems to identify road friction estimates which are reported to the central server—where the vehicles use sensor data and vehicle dynamic conditions to estimate friction. The central server stores and aggregates the friction data, filters it and ages it. Vehicles requesting advisories from the central server will receive notices of road friction conditions which may be significant based on their location and heading. Driver warnings can be issued for low friction conditions ahead, and automated vehicle systems may also respond to the notices.

First claim

What is claimed is:

1. A method for estimating road friction conditions using vehicular participative sensing systems, said method comprising:
providing data about road friction conditions by a plurality of participative sensing system vehicles;
collecting, on a server computer including a processor and memory, the data about the road friction conditions from the participative sensing system vehicles;
analyzing the data about the road friction conditions, by the server computer, to determine consensus road friction estimates;
issuing road friction advisories from the server computer to advisory-receiving vehicles and other entities, where the road friction advisories include the consensus road friction estimate for a particular road and location, including issuing advisories of low-friction conditions to a road commission which has responsibility for a road on which the low-friction condition exists, and the advisories to the road commission include advisories of low-friction conditions needing immediate attention including snow plowing and road salt, and electronic sign message content, and advisories of chronic low-friction conditions needing long-term attention including road design changes and permanent road sign changes;
using the road friction advisories as input to traction-related systems in the advisory-receiving vehicles; and
notifying drivers of the advisory-receiving vehicles of any low-friction conditions described in the advisories.

2. The method of claim 1 wherein providing data about road friction conditions includes monitoring data from vehicle sensors and systems, identifying a trigger event, computing a road friction value, and communicating the road friction value and a vehicle location to the server computer.

3. The method of claim 2 wherein monitoring data from vehicle sensors and systems includes monitoring data from vehicle dynamics sensors, data from environmental sensors, and data from vehicle systems available on a vehicle data bus.

4. The method of claim 1 wherein providing data about road friction conditions includes determining whether the participative sensing system vehicle is in an operating regime which is linear or nonlinear, determining whether the participative sensing system vehicle is driving in a path which is straight or curved, and computing a coefficient of friction value in a manner which is dependent on the operating regime and the path.

5. The method of claim 1 wherein analyzing the data about the road friction conditions to determine consensus road friction estimates includes aggregating the data, filtering the data, applying a time-decay to the data and purging the data.

6. The method of claim 1 wherein analyzing the data about the road friction conditions to determine consensus road friction estimates includes computing the consensus road friction estimates as a function of current data about the road friction conditions from the participative sensing system vehicles, historical data about the road friction conditions from the participative sensing system vehicles and friction-relevant data from online sources including weather data.

7. The method of claim 6 wherein the function used to compute the consensus road friction estimates is an intersection-based function which considers only the data about the road friction conditions which are applicable for each particular road and location.

8. The method of claim 1 wherein using the road friction advisories as input to traction-related systems in the advisory-receiving vehicles includes using the consensus road friction estimate contained in the advisories as input to a stability control system, an anti-lock brake system, a traction control system and a transmission mode selection system.

9. A method for estimating road friction conditions using vehicular participative sensing systems, said method comprising:
providing data about road friction conditions by a plurality of participative sensing system vehicles, including monitoring data from vehicle sensors and systems, identifying a trigger event, computing a road friction value, and communicating the road friction value and a vehicle location to the server computer;
collecting, on a server computer including a processor and memory, the data about the road friction conditions from the participative sensing system vehicles;
analyzing the data about the road friction conditions, by the server computer, to determine consensus road friction estimates;
issuing road friction advisories from the server computer to advisory-receiving vehicles, where the road friction advisories include the consensus road friction estimate for a particular road and location;
using the road friction advisories as input to traction-related systems in the advisory-receiving vehicles;
notifying drivers of the advisory-receiving vehicles of any low-friction conditions described in the advisories; and
issuing advisories of low-friction conditions from the server computer to a road commission which has responsibility for a road on which the low-friction condition exists, where the advisories include advisories of low-friction conditions needing immediate attention including snow plowing and road salt, and electronic sign message content, and advisories of chronic low-friction conditions needing long-term attention including road design changes and permanent road sign changes.

10. The method of claim 9 wherein providing data about road friction conditions includes determining whether the participative sensing system vehicle is in an operating regime which is linear or nonlinear, determining whether the participative sensing system vehicle is driving in a path which is straight or curved, and computing a coefficient of friction value in a manner which is dependent on the operating regime and the path.

11. The method of claim 9 wherein analyzing the data about the road friction conditions to determine consensus road friction estimates includes computing the consensus road friction estimates as a function of current data about the road friction conditions from the participative sensing system vehicles, historical data about the road friction conditions from the participative sensing system vehicles and friction-relevant data from online sources including weather data.

12. A vehicular participative sensing system for estimating road friction conditions, said system comprising:
a plurality of participative sensing system vehicles with sensors and a processor configured to provide data about road friction conditions, where the processor monitors data from vehicle dynamics sensors, data from environmental sensors, and data from vehicle systems available on a vehicle data bus, said participative sensing system vehicles also including a wireless communications system for communicating the data about the road friction conditions;
a server computer including a processor and memory, said server computer being configured to receive the data about the road friction conditions from the participative sensing system vehicles, analyze the data about the road friction conditions to determine consensus road friction estimates, and issue road friction advisories to advisory-receiving vehicles and other entities, where the road friction advisories include the consensus road friction estimate for a particular road and location, and where the server computer is configured to issue the advisories to a road commission which has responsibility for a road on which the low-friction condition exists, where the advisories include advisories of low-friction conditions needing immediate attention including snow plowing and road salt, and electronic sign message content, and advisories of chr

Assignees

• Gm Global Tech Operations Llc

Inventors

• Grimm Donald K
• Ghoneim Youssef A
• Bai Fan
• Chen Jinzhu

Classifications

• B60W2552/40

  Coefficient of friction · CPC title

• G08G1/096716

  where the received information does not generate an automatic action on the vehicle control · CPC title

• G08G1/0112 Primary

  from the vehicle, e.g. floating car data [FCD] · CPC title

• B60T8/172

  Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters {(B60T8/17551 takes precedence)} · CPC title

• B60W40/068 Primary

  Road friction coefficient · CPC title