LIDAR sensor frost detection

• US 10,209,709 B2
• Filed: 08/15/2016
• Issued: 02/19/2019
• Est. Priority Date: 08/15/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Peters, Cindy Anne, Nichols, Mark Edward, Peczonczyk, Sabrina Louise, Holguin, Kerrie Nikaido, Kayser, Elyssa
• Primary Examiner(s): Weber, Tamara L
• Application Number:
  US15/236,701
• Publication Number:
  US 20180046183A1
• Time in Patent Office: 918 Days
• Field of Search: None
• CPC Class Codes: B60S 1/56 specially adapted for cleaning other parts or devices than front windows or windscreens rear-view mirror arrangements mounted on vehicle exterior including cleaning devices B60R1/0602
• CPC Class Codes: B60W 2050/0043 Signal treatments, identification of variables or parameters, parameter estimation or state estimation
• CPC Class Codes: B60W 2050/0215 Sensor drifts or sensor failures
• CPC Class Codes: B60W 2420/408 Radar; Laser, e.g. lidar
• CPC Class Codes: B60W 2555/20 Ambient conditions, e.g. wind or rain
• CPC Class Codes: B60W 30/182 Selecting between different operative modes, e.g. comfort and performance modes
• CPC Class Codes: B60W 50/0205 Diagnosing or detecting failures; Failure detection models
• CPC Class Codes: B60W 50/0225 Failure correction strategy
• CPC Class Codes: B60W 50/032 Fixing failures by repairing failed parts, e.g. loosening a sticking valve
• CPC Class Codes: B60W 60/0059 Estimation of the risk associated with autonomous or manual driving, e.g. situation too complex, sensor failure or driver incapacity
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 17/95 for meteorological use
• CPC Class Codes: G01S 2007/4977 including means to prevent or remove the obstruction
• CPC Class Codes: G01S 7/497 Means for monitoring or calibrating
• CPC Class Codes: G05D 1/0061 for transition from automatic pilot to manual pilot and vice versa

Abstract

A vehicle system includes a processor programmed to receive sensor signals from a LIDAR sensor. The processor estimates frost accumulation on the LIDAR sensor from the sensor signals and compares the estimated frost accumulation to a predetermined threshold. The processor further prevents a host vehicle from operating in an autonomous mode if the estimated frost accumulation exceeds the predetermined threshold.

Claims

1. A vehicle system comprising:

a LIDAR sensor having a lens; and

a processor programmed to receive sensor signals from the LIDAR sensor, estimate frost accumulation on the LIDAR sensor from the sensor signals, compare the estimated frost accumulation to a predetermined threshold representing an amount of frost accumulation on the lens of the LIDAR sensor, output a defrost signal to the LIDAR sensor to command the LIDAR sensor to execute a defrost operation as a result of determining that the frost accumulation exceeds the predetermined threshold, prevent a host vehicle from operating in an autonomous mode as a result of determining that the estimated frost accumulation exceeds the predetermined threshold, and output a signal to a user interface located in the host vehicle instructing a vehicle occupant to manually remove the frost from the lens of the LIDAR sensor to resume autonomous operation of the host vehicle,

wherein the processor is programmed to prevent the host vehicle from operating in the autonomous mode by outputting a signal instructing an autonomous mode controller to prohibit autonomous operation of the host vehicle, and

wherein the LIDAR sensor executes the defrost operation to melt the frost on the lens of the LIDAR sensor.

2. The vehicle system of claim 1, wherein the processor is programmed to periodically receive sensor signals from the LIDAR sensor while the host vehicle is operating in a non-autonomous mode.

3. The vehicle system of claim 2, wherein the processor is programmed to periodically estimate the frost accumulation on the LIDAR sensor while the host vehicle is operating in the non-autonomous mode.

4. The vehicle system of claim 3, wherein the processor is programmed to permit the host vehicle to operate in the autonomous mode while the frost accumulation is below the predetermined threshold.

5. The vehicle system of claim 1, wherein the processor is programmed to periodically receive sensor signals from the LIDAR sensor while the host vehicle is operating in the autonomous mode.

6. The vehicle system of claim 5, wherein the processor is programmed to periodically estimate the frost accumulation on the LIDAR sensor while the host vehicle is operating in the autonomous mode.

7. The vehicle system of claim 6, wherein the processor is programmed to permit the host vehicle to remain operating in the autonomous mode so long as the frost accumulation is below the predetermined threshold.

8. A method comprising:

detecting an environmental condition including at least one of an ambient temperature and an ambient humidity;

receiving sensor signals from a LIDAR sensor;

estimating frost accumulation on the LIDAR sensor from the sensor signals as a result of detecting the environmental condition;

comparing the estimated frost accumulation to a predetermined threshold representing an amount of frost accumulation associated with interfering with an accuracy of the LIDAR sensor;

activating a defrost operation of the LIDAR sensor as a result of determining that the frost accumulation exceeds the predetermined threshold;

preventing a host vehicle from operating in an autonomous mode as a result of determining that the estimated frost accumulation exceeds the predetermined threshold, wherein preventing the host vehicle from operating in the autonomous mode includes instructing an autonomous mode controller to prohibit autonomous operation of the host vehicle; and

outputting a signal to a user interface located in the host vehicle instructing a vehicle occupant to manually remove the frost from the lens of the LIDAR sensor to resume autonomous operation of the host vehicle.

9. The method of claim 8, wherein activating the defrost operation includes outputting a defrost signal commanding the LIDAR sensor to execute the defrost operation if the estimated frost accumulation exceeds the predetermined threshold.

10. The method of claim 8, wherein receiving the sensor signals includes periodically receiving sensor signals from the LIDAR sensor while the host vehicle is operating in a non-autonomous mode.

11. The method of claim 10, wherein estimating the frost accumulation includes periodically estimating the frost accumulation on the LIDAR sensor while the host vehicle is operating in the non-autonomous mode.

12. The method of claim 11, further comprising permitting the host vehicle to operate in the autonomous mode while the frost accumulation is below the predetermined threshold.

13. The method of claim 8, wherein receiving the sensor signals includes periodically receiving sensor signals from the LIDAR sensor while the host vehicle is operating in the autonomous mode.

14. The method of claim 13, wherein estimating the frost accumulation includes periodically estimating the frost accumulation on the LIDAR sensor while the host vehicle is operating in the autonomous mode.

15. The method of claim 14, further comprising permitting the host vehicle to remain operating in the autonomous mode so long as the frost accumulation is below the predetermined threshold.

16. A vehicle computer comprising a processor and a memory storing instructions executable by the processor, the instructions including:

detecting an environmental condition including at least one of an ambient temperature and an ambient humidity;

receiving sensor signals from a LIDAR sensor;

estimating frost accumulation on the LIDAR sensor from the sensor signals as a result of detecting the environmental condition;

comparing the estimated frost accumulation to a predetermined threshold representing an amount of frost accumulation associated with interfering with an accuracy of the LIDAR sensor;

activating a defrost operation of the LIDAR sensor as a result of determining that the frost accumulation exceeds the predetermined threshold;

preventing a host vehicle from operating in an autonomous mode if the estimated frost accumulation exceeds the predetermined threshold, wherein preventing the host vehicle from operating in the autonomous mode includes instructing an autonomous mode controller to prohibit autonomous operation of the host vehicle; and

outputting a signal to a user interface located in the host vehicle instructing a vehicle occupant to manually remove the frost from the lens of the LIDAR sensor to resume autonomous operation of the host vehicle.

17. The vehicle computer of claim 16, wherein activating the defrost operation includes outputting a defrost signal commanding the LIDAR sensor to execute the defrost operation as a result of determining that the estimated frost accumulation exceeds the predetermined threshold.

18. The vehicle computer of claim 16, wherein receiving the sensor signals includes periodically receiving sensor signals from the LIDAR sensor while the host vehicle is operating in a non-autonomous mode, and wherein estimating the frost accumulation includes periodically estimating the frost accumulation on the LIDAR sensor while the host vehicle is operating in the non-autonomous mode, the instructions further comprising permitting the host vehicle to operate in the autonomous mode while the frost accumulation is below the predetermined threshold.

19. The vehicle computer of claim 16, wherein receiving the sensor signals includes periodically receiving sensor signals from the LIDAR sensor while the host vehicle is operating in the autonomous mode, and wherein estimating the frost accumulation includes periodically estimating the frost accumulation on the LIDAR sensor while the host vehicle is operating in the autonomous mode, the instructions further comprising permitting the host vehicle to remain operating in the autonomous mode so long as the frost accumulation is below the predetermined threshold.