Sensor cleaning device

Abstract

To satisfactorily clean the outer surface of an on-vehicle sensor using air jets while considering the influence of travel wind.SOLUTION: A sensor cleaning device which cleans an outer surface of an on-vehicle sensor, Includes: the on-vehicle sensor; a plurality of air nozzles facing the outer surface from multiple directions; a pump; a plurality of actuators that adjust a flow amount of air; and an electronic control unit. In air cleaning control, when dirt on the outer surface is detected by the on-vehicle sensor, the electronic control unit controls the pump and the plurality of actuators so that the first air jet of jetting air from all of the plurality of air nozzles is executed. Meanwhile, when residual dirt on the outer surface is detected by the on-vehicle sensor after the first air jet, the electronic control unit determines the flow amount of the air for the second air jet on the basis of distribution information of the residual dirt acquired by the on-vehicle sensor, and controls the pump and the plurality of actuators so that the second air jet is executed.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a sensor cleaning device that is installed outside the vehicle cabin and cleans the surface of an in-vehicle sensor that recognizes the surrounding situation of the vehicle.

Background Art

[0002] Patent Document 1 discloses a sensor cleaning device. This device includes a set of liquid nozzles for injecting liquid onto the lens of the sensor and a slit opening for injecting air onto the lens.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When having a structure for cleaning an in-vehicle sensor with air like the device described in Patent Document 1, if the vehicle is traveling at high speed, the cleaning by air injection may be greatly affected by the traveling wind. As a result, a situation may occur where it is difficult to clean the outer surface of the in-vehicle sensor well using air injection.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a sensor cleaning device that can clean the outer surface of an in-vehicle sensor well using air injection while considering the influence of the traveling wind.

Means for Solving the Problems

[0006] The sensor cleaning device according to the present disclosure is configured to clean the outer surface of an in-vehicle sensor. The in-vehicle sensor is installed outside the vehicle cabin and recognizes the surrounding situation of the vehicle. The sensor cleaning device includes, together with the in-vehicle sensor, a plurality of air nozzles, a pump, a plurality of actuators, and an electronic control unit. The plurality of air nozzles are arranged so as to face the outer surface from a plurality of directions. The pump supplies air to the plurality of air nozzles. The plurality of actuators adjust the flow rate of the air supplied to the plurality of air nozzles. The electronic control unit executes air cleaning control for cleaning the outer surface. In the air cleaning control, when dirt on the outer surface is detected by the in-vehicle sensor, the electronic control unit controls the pump and the plurality of actuators so that a first air injection for injecting air from all of the plurality of air nozzles is executed. On the other hand, when remaining dirt on the outer surface is detected by the in-vehicle sensor after the first air injection, the electronic control unit determines the flow rate of the air supplied to each of the plurality of air nozzles for the second air injection based on the distribution information of the remaining dirt acquired by the in-vehicle sensor, and controls the pump and the plurality of actuators so that the second air injection is executed.

Effects of the Invention

[0007] According to the sensor cleaning device according to the present disclosure, by executing the above-described air cleaning control, it is possible to satisfactorily clean the outer surface of the in-vehicle sensor by using air injection while considering the influence of the traveling wind.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Modes for Carrying Out the Invention

[0009] Embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0010] 1. Configuration of Sensor Cleaning Device FIG. 1 is a diagram schematically showing an example of the configuration of a sensor cleaning device 10 according to an embodiment. The sensor cleaning device 10 is mounted on a vehicle 1. The vehicle 1 includes a Lidar sensor 2 disposed outside the vehicle compartment as shown in FIG. 1. The Lidar (Laser imaging detection and ranging) sensor 2 is an example of an "in-vehicle sensor for recognizing the surrounding situation of the vehicle". The vehicle 1 is, for example, an autonomous vehicle capable of performing autonomous driving using sensor information such as the Lidar sensor 2. As an example, the Lidar sensor 2 is installed at a location such as the roof of the vehicle 1 so as to face the front of the vehicle. In other examples, the "in-vehicle sensor" may be a camera.

[0011] The sensor cleaning device 10 is a device for cleaning the outer surface (or sensor surface) 3 of the Lidar sensor 2. The sensor cleaning device 10 includes the Lidar sensor 2, a plurality of air nozzles 12, a pump 14, an air hose 16, a plurality of solenoid valves 18, and an electronic control unit (ECU) 20. In the example shown in FIG. 1, the number of air nozzles 12 and solenoid valves 18 is five each, but may be a plurality other than five.

[0012] The five air nozzles 12 are arranged to face the sensor surface 3 from five directions corresponding to the number of air nozzles 12. More specifically, as shown in FIG. 1, each air nozzle 12 is arranged to face the center of the sensor surface 3.

[0013] The pump 14 is, for example, an electric pump. Each air nozzle 12 is connected to the pump 14 via the air hose 16. The pump 14 operates based on a command from the ECU 20 and pumps air toward each air nozzle 12. Each air nozzle 12 injects (sprays) the air supplied from the pump 14 onto the sensor surface 3.

[0014] The five solenoid valves 18 adjust the flow rate Ga of the air supplied to the five air nozzles 12 respectively. The adjustment of the air flow rate Ga by each solenoid valve 18 includes closing the solenoid valve 18 to make the flow rate Ga zero. The solenoid valve 18 is configured to be adjustable continuously or stepwise, for example. Alternatively, the solenoid valve 18 may be configured to be switchable between an open state and a closed state. The five solenoid valves 18 correspond to an example of the "plurality of actuators" according to the present disclosure.

[0015] The ECU 20 includes a processor and a memory, and executes "air cleaning control" for cleaning the sensor surface 3. In the present embodiment, the ECU 20 is an ECU that performs automatic driving control of the vehicle 1. However, the ECU 20 may be provided separately from the ECU that performs automatic driving control and be an ECU that performs air cleaning control.

[0016] 2. Air cleaning control FIG. 2 is a flowchart showing an example of the process related to the air cleaning control according to the embodiment. The process of this flowchart is executed by the ECU 20, for example, during the execution of the automatic driving of the vehicle 1.

[0017] In step S100, the ECU 20 determines whether the dirt on the sensor surface 3 is detected by the Lidar sensor 2. The dirt here is, for example, raindrops or dust. Specifically, the Lidar sensor 2 is configured to analyze the point cloud data to detect the dirt attached to the sensor surface 3. When the dirt is detected, the Lidar sensor 2 transmits the dirt detection information to the ECU 20. When receiving this dirt detection information, the ECU 20 determines that the dirt is detected. As a result, the process proceeds to step S102.

[0018] In step S102, the ECU 20 controls the pump 14 and each solenoid valve 18 so that the first air injection (the first-time air injection) is executed. The "first air injection" mentioned here is to inject air from all the air nozzles 12. Specifically, for the execution of the first air injection, the ECU 20 operates the pump 14 and controls each solenoid valve 18 to open at a predetermined opening degree (for example, the maximum opening degree). As a result, air is injected from each air nozzle 12 toward the sensor surface 3. Additionally, for example, the "predetermined opening degree" is an equal opening degree among the solenoid valves 18. As a result, air of equal strength is injected from each air nozzle 12.

[0019] In step S104 following step S102, the ECU 20 determines whether residual dirt on the sensor surface 3 is detected by the Lidar sensor 2. That is, it is determined whether dirt remains on the sensor surface 3 despite the previous air injection (the first or second air injection) performed by the process of step S102 or step S108 described later. Also in this step S104, when the ECU 20 receives dirt detection information from the Lidar sensor 2, it determines that residual dirt is detected. As a result, the process proceeds to step S106. On the other hand, when the dirt detection information is not received, that is, when no residual dirt is detected, the process proceeds to the end. As a result, the current air cleaning control ends.

[0020] In step S106, the ECU 20 determines the air flow rate Ga supplied to each air nozzle 12 for the second air injection (the second-time or subsequent air injection) based on the distribution information of the residual dirt acquired by the Lidar sensor 2.

[0021] The distribution information of the residual dirt is used as follows for the determination of the flow rate Ga. That is, it can be said that the distribution information of the residual dirt indicates the dirt removal result by the previous air injection. Therefore, the Lidar sensor 2 (its processor) executes a process of analyzing the influence of the traveling wind on the air cleaning based on the distribution information.

[0022] Specifically, the Lidar sensor 2 analyzes the influence of the traveling wind and obtains information indicating the direction and strength of the traveling wind. For example, if it is known from the distribution information that there is a lot of dirt distributed near the injection port of a certain air nozzle 12, it can be determined that there is an influence of the traveling wind flowing toward the side of the air nozzle 12. Also, for example, when the dirt density at a position near the injection port of a certain air nozzle 12 is high, it can be determined that there is an influence of a strong traveling wind compared to when the density is low. Also, for example, when the position of the dirt relative to the injection port of a certain air nozzle 12 is close, it can be determined that there is an influence of a strong traveling wind compared to when the position is far. The Lidar sensor 2 detects, based on the distribution information, the position and density of dirt such as described above, and as a result of the analysis, generates information indicating, for example, the direction and strength of the traveling wind. Then, the Lidar sensor 2 transmits the generated information to the ECU 20. Note that the processing for the analysis may be executed on the side of the ECU 20.

[0023] Furthermore, in this step S106, the ECU 20 determines the flow rate Ga of the air supplied to each air nozzle 12 based on the above-described analysis result of the influence of the traveling wind (for example, information on the direction and strength of the traveling wind). For example, the ECU 20 controls the opening degree of each solenoid valve 18 so that the flow rate Ga supplied to the air nozzle 12 having an injection port facing the direction opposite to the direction of the traveling wind based on the analysis result is larger than that of the other air nozzles 12. Alternatively, for example, the ECU 20 may control the opening degree of each solenoid valve 18 so that the stronger the traveling wind flowing in the direction facing the injection port, the larger the flow rate Ga supplied to the air nozzle 12 having the injection port is compared to the other air nozzles 12. The flow rate Ga mentioned here includes 0. For example, the ECU 20 may set the flow rate Ga supplied to the air nozzle 12 that is not affected or is less affected by the traveling wind to 0. That is, the ECU 20 may close the solenoid valve 18 corresponding to the air nozzle 12.

[0024] In step S108 following step S106, the ECU 20 controls the pump 14 and each solenoid valve 18 so that a second air injection according to the flow rate Ga determined in step S106 is executed.

[0025] After step S108, the process returns to step S104. As a result, when residual dirt is detected again in step S104, the processes of steps S106 and S108 are executed. On the other hand, when residual dirt is no longer detected in step S104 (step S104; No), the air cleaning control ends. Thus, while residual dirt is detected, a second air injection (the second air injection) is repeatedly executed.

[0026] As described above, according to the air cleaning control according to the present embodiment, it is possible to satisfactorily clean the outer surface 3 of the Lidar sensor 2 (in-vehicle sensor) using air injection while considering the influence of the traveling wind. Thereby, it is possible to realize the sensor cleaning device 10 that is less affected by the traveling wind.

Explanation of Signs

[0027] 1 Vehicle, 2 Lidar sensor (in-vehicle sensor), 3 Sensor surface, 10 Sensor cleaning device, 12 Air nozzle, 14 Pump, 16 Air hose, 18 Solenoid valve, 20 Electronic control unit (ECU)

Claims

【Claim 1】 A sensor cleaning device for cleaning the outer surface of an in-vehicle sensor installed outside the vehicle cabin to recognize the situation around the vehicle, comprising: the in-vehicle sensor; a plurality of air nozzles arranged to face the outer surface from a plurality of directions; a pump for supplying air to the plurality of air nozzles; a plurality of actuators for adjusting the flow rate of the air supplied to the plurality of air nozzles; an electronic control unit for executing air cleaning control for cleaning the outer surface; and in the air cleaning control, the electronic control unit controls the pump and the plurality of actuators so that a first air injection for injecting air from all of the plurality of air nozzles is executed when dirt on the outer surface is detected by the in-vehicle sensor; when remaining dirt on the outer surface is detected by the in-vehicle sensor after the first air injection, based on the distribution information of the remaining dirt acquired by the in-vehicle sensor, determines the flow rate of the air supplied to each of the plurality of air nozzles for a second air injection, and controls the pump and the plurality of actuators so that the second air injection is executed sensor cleaning device.

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