SENSOR CLEANING AND COOLING

A system includes a computer including a processor and a memory, the memory storing instructions executable by the processor to determine an amount of occluding material on a vehicle sensor, determine a temperature of the vehicle sensor, and actuate a liquid pump arranged to pump liquid to the vehicle sensor and an air pump arranged to pump air to the vehicle sensor based on the amount of occluding material and the temperature.

BACKGROUND

Vehicles, such as passenger cars, typically include sensors to collect data about a surrounding environment. The sensors can be placed on or in various parts of the vehicle, e.g., a vehicle roof, a vehicle hood, a rear vehicle door, etc. The sensors, e.g., sensor lens covers, may become dirty during operation of the vehicle. Furthermore, the sensors may increase in temperature based on current environmental conditions. During vehicle operation, sensor data and/or environmental conditions around a vehicle can be changing, and such changes can affect sensor operation. It is a problem to process the various factors and to maintain sensors in a usable condition.

DETAILED DESCRIPTION

A system includes a computer including a processor and a memory, the memory storing instructions executable by the processor to determine an amount of occluding material on a vehicle sensor, determine a temperature of the vehicle sensor, and actuate a liquid pump arranged to pump liquid to the vehicle sensor and an air pump arranged to pump air to the vehicle sensor based on the amount of occluding material and the temperature.

The instructions can further include instructions to pump liquid through a liquid tube extending around the vehicle sensor.

The instructions can further include instructions to actuate a diverter valve to pump liquid and air through an opening in a sensor housing onto the vehicle sensor. The instructions can further include instructions to actuate the diverter valve when the amount of occluding material exceeds an occluding material threshold.

The instructions can further include instructions to deactivate the sensor when the temperature exceeds a temperature threshold.

The instructions can further include instructions to actuate the liquid pump to a specified liquid pump duty cycle based on the amount of occluding material and the temperature.

The instructions can further include instructions to actuate the air pump to a specified air pump duty cycle based on the amount of occluding material and the temperature.

The instructions can further include instructions to, when the temperature is above a temperature threshold and the amount of occluding material is above an occluding material threshold, actuate the liquid pump and the air pump to cool the vehicle sensor. The instructions can further include instructions to determine a second temperature of the vehicle sensor and, when the second temperature is below the temperature threshold, actuate a diverter valve to pump liquid and air through an opening in a sensor housing onto the vehicle sensor.

A system includes a sensor housing including a fluid opening, a vehicle sensor disposed the sensor housing, a liquid pump disposed in the sensor housing, an air pump disposed in the sensor housing, a liquid tube connected to the liquid pump extending around the vehicle sensor, an air tube connected to the air pump and the fluid opening, means for determining an amount of occluding material on the vehicle sensor, means for determining a temperature of the vehicle sensor, and means for actuating the liquid pump and the air pump based on the amount of occluding material and the temperature.

The system can further include means for actuating a diverter valve to pump liquid and air through the fluid opening onto the vehicle sensor.

The system can further include means for deactivating the sensor when the temperature exceeds a temperature threshold.

The system can further include means for actuating the liquid pump and the air pump to cool the vehicle sensor when the temperature is above a temperature threshold and the amount of occluding material is above an occluding material threshold.

The system can further include means for determining a second temperature of the vehicle sensor and means for actuating a diverter valve to pump liquid and air through an opening in a sensor housing onto the vehicle sensor when the second temperature is below a temperature threshold.

A method includes determining an amount of occluding material on a vehicle sensor, determining a temperature of the vehicle sensor, and actuating a liquid pump to pump liquid to the vehicle sensor and an air pump to pump air to the vehicle sensor based on the amount of occluding material and the temperature.

The method can further include pumping liquid through a liquid tube extending around the vehicle sensor.

The method can further include actuating a diverter valve to pump liquid and air through an opening in a sensor housing onto the vehicle sensor. The method can further include actuating the diverter valve when the amount of occluding material exceeds an occluding material threshold.

The method can further include deactivating the sensor when the temperature exceeds a temperature threshold.

The method can further include, when the temperature is above a temperature threshold and the amount of occluding material is above an occluding material threshold, actuating the liquid pump and the air pump to cool the vehicle sensor.

To cool and clean a sensor, a computer can selectively actuate a liquid pump, an air pump, and a diverter valve to clean and/or cool the sensor based on the temperature of the sensor and the amount of occluding material on the sensor. When the computer determines to cool the sensor and not to clean the sensor, the computer can actuate the diverter valve to direct liquid into a cooling tube to cool the sensor with convection cooling. When the computer determines to clean the sensor but not to cool the sensor, the computer can actuate the diverter valve to direct the liquid into a mixing tube to mix with air and spray onto a surface of the sensor to clean the sensor. When the computer determines to clean and cool the sensor, the computer can actuate the diverter valve to direct the liquid to both the cooling tube and the mixing tube to cool and clean the sensor. The computer can, based on the temperature of the sensor and the amount of occluding material on the sensor, prioritize one of cleaning and cooling the sensor and actuate the diverter valve, the air pump, and the liquid pump to direct the liquid accordingly. Furthermore, as the sensor cools and is cleaned, the computer can actuate the diverter valve, the air pump, and the liquid pump based on a current amount of occluding material and a current temperature of the sensor.

FIG. 1illustrates an example system100for operating a sensor110in a vehicle101. A computer105in the vehicle101is programmed to receive collected data115from one or more sensors110. For example, vehicle101data115may include a location of the vehicle101, data about an environment around a vehicle, data about an object outside the vehicle such as another vehicle, etc. A vehicle101location is typically provided in a conventional form, e.g., geo-coordinates such as latitude and longitude coordinates obtained via a navigation system that uses the Global Positioning System (GPS). Further examples of data115can include measurements of vehicle101systems and components, e.g., a vehicle101velocity, a vehicle101trajectory, etc.

The computer105is generally programmed for communications on a vehicle101network, e.g., including a conventional vehicle101communications bus. Via the network, bus, and/or other wired or wireless mechanisms (e.g., a wired or wireless local area network in the vehicle101), the computer105may transmit messages to various devices in a vehicle101and/or receive messages from the various devices, e.g., controllers, actuators, sensors, etc., including sensors110. Alternatively or additionally, in cases where the computer105actually comprises multiple devices, the vehicle network may be used for communications between devices represented as the computer105in this disclosure. In addition, the computer105may be programmed for communicating with the network125, which, as described below, may include various wired and/or wireless networking technologies, e.g., cellular, Bluetooth®, Bluetooth® Low Energy (BLE), wired and/or wireless packet networks, etc.

The data store106can be of any type, e.g., hard disk drives, solid state drives, servers, or any volatile or non-volatile media. The data store106can store the collected data115sent from the sensors110.

Sensors110can include a variety of devices. For example, various controllers in a vehicle101may operate as sensors110to provide data115via the vehicle101network or bus, e.g., data115relating to vehicle speed, acceleration, position, subsystem and/or component status, etc. Further, other sensors110could include cameras, motion detectors, etc., i.e., sensors110to provide data115for evaluating a position of a component, evaluating a slope of a roadway, etc. The sensors110could, without limitation, also include short range radar, long range radar, LIDAR, and/or ultrasonic transducers.

Collected data115can include a variety of data collected in a vehicle101. Examples of collected data115are provided above, and moreover, data115are generally collected using one or more sensors110, and may additionally include data calculated therefrom in the computer105, and/or at the server130. In general, collected data115may include any data that may be gathered by the sensors110and/or computed from such data.

The vehicle101can include a plurality of vehicle components120. In this context, each vehicle component120includes one or more hardware components adapted to perform a mechanical function or operation—such as moving the vehicle101, slowing or stopping the vehicle101, steering the vehicle101, etc. Non-limiting examples of components120include a propulsion component (that includes, e.g., an internal combustion engine and/or an electric motor, etc.), a transmission component, a steering component (e.g., that may include one or more of a steering wheel, a steering rack, etc.), a brake component, a park assist component, an adaptive cruise control component, an adaptive steering component, a movable seat, and the like.

When the computer105operates the vehicle101, the vehicle101is an “autonomous” vehicle101. For purposes of this disclosure, the term “autonomous vehicle” is used to refer to a vehicle101operating in a fully autonomous mode. A fully autonomous mode is defined as one in which each of vehicle101propulsion (typically via a powertrain including an electric motor and/or internal combustion engine), braking, and steering are controlled by the computer105. A semi-autonomous mode is one in which at least one of vehicle101propulsion (typically via a powertrain including an electric motor and/or internal combustion engine), braking, and steering are controlled at least partly by the computer105as opposed to a human operator. In a non-autonomous mode, i.e., a manual mode, the vehicle101propulsion, braking, and steering are controlled by the human operator.

The system100can further include a wide-area network125connected to a server130and a data store135. The computer105can further be programmed to communicate with one or more remote sites such as the server130, via the network125, such remote site possibly including a data store135. The network125represents one or more mechanisms by which a vehicle computer105may communicate with a remote server130. Accordingly, the network125can be one or more of various wired or wireless communication mechanisms, including any desired combination of wired (e.g., cable and fiber) and/or wireless (e.g., cellular, wireless, satellite, microwave, and radio frequency) communication mechanisms and any desired network topology (or topologies when multiple communication mechanisms are utilized). Exemplary communication networks include wireless communication networks (e.g., using Bluetooth®, Bluetooth® Low Energy (BLE), IEEE 802.11, vehicle-to-vehicle (V2V) such as Dedicated Short Range Communications (DSRC), etc.), local area networks (LAN) and/or wide area networks (WAN), including the Internet, providing data communication services.

The vehicle101includes a liquid pump140. The liquid pump140can move liquid to the sensors110. The computer105can actuate the liquid pump140to cool and clean the sensors110, as described below. For example, the computer105can actuate the liquid pump140to move the liquid around the sensors110, cooling the sensors110with liquid convection cooling. The liquid pump140can pump, e.g., water, a cleaning liquid, a coolant, etc., to cool and clean the sensors110.

The vehicle101includes an air pump145. The air pump145can move air to the sensors110. The computer105can actuate the air pump145to cool and clean the sensors110, as described below. For example, the computer105can actuate the air pump145to move air across a surface of the sensors110, cooling the sensors110with gas convection cooling. As described below, the computer105can actuate both the liquid pump140and the air pump145to cool and clean the sensors110.

The computer105can actuate the liquid pump140and the air pump145to specified respective duty cycles. As used herein, a “duty cycle” is value between and including 0 and 1, representing a portion of a maximum operation of the liquid pump140and the air pump145. When the duty cycle is 0, the liquid pump140or the air pump145is deactivated. When the duty cycle is 1, the liquid pump140or the air pump145operates at a respective predetermined maximum capacity, e.g., the liquid pump140moves as much liquid as allowed by the predetermined maximum capacity, the air pump145moves as much air as allowed by the predetermined maximum capacity, etc. The predetermined maximum capacity can be determined by, e.g., empirical tests, ratings from a manufacturer, material strength, etc., and can be stored in the data store106and/or the server130. When the duty cycle is a value between 0 and 1, the liquid pump140or the air pump145operates at the proportion of the predetermined maximum capacity specified by the duty cycle, e.g., if the duty cycle is 30%, the liquid pump140or the air pump145operates at 30% of the predetermined maximum capacity.

The computer105can determine the duty cycle for the liquid pump140(i.e., the liquid pump140duty cycle) and the duty cycle for the air pump (i.e., the air pump145duty cycle) based on a temperature of the sensor110and an amount of occluding material on the sensor110, as described below. As used herein, “occluding material” is material that can reduce the data and/or the quality of data collected by the sensors110when present on the sensors110, e.g., dirt, dust, debris, mud, fog, dew, sand, frost, ice, grime, precipitation, moisture, etc.

FIG. 2illustrates an example vehicle101. The vehicle101can be, e.g., an automobile, including a sedan, a pick-up truck, a sport-utility vehicle, etc. The vehicle101can be an autonomous vehicle101. For example, the vehicle101can have a computer105that may control the operations of the vehicle10in an autonomous mode, a semi-autonomous mode, or a non-autonomous mode.

The vehicle101includes a sensor housing200. The sensor housing200is fixed to the vehicle101, e.g., on a vehicle101roof. The sensor housing200is a support structure or the like that can house a plurality of sensors110, e.g., one or more cameras and one or more lidar sensors. The sensor housing200can secure the sensors110in a fixed orientation to collect data115in a specific direction relative to the vehicle101. The sensors110can collect occluding material, reducing the amount of data115and/or the precision of the data115collected by the sensors110.

FIG. 3illustrates an example sensor110in the sensor housing200. The sensor housing200includes a sensor manifold205. The sensor manifold205supports the sensor110. The sensor manifold205can be, e.g., a circular indentation in the sensor housing200into which the sensor110is placed. The sensor manifold205can, as described below, allow air and liquid to move to the sensor110.

The sensor manifold205can include a nozzle210. The nozzle210sprays air and/or liquid onto the sensor110. The nozzle210includes an opening215that allows a fluid (e.g., air, a cleaning liquid, etc.) to move through the nozzle210and onto the sensor110. The nozzle210can be connected to the liquid pump140and the air pump145, as described below. The sensor manifold205can include a plurality of nozzles210, e.g., four nozzles210as shown inFIG. 3, or a different number of nozzles210. The nozzles210can be directed to spray the air and/or the liquid vertically along a surface of the sensor110.

The sensor manifold205can include a liquid tube220. The liquid tube220is connected to the liquid pump140. The liquid tube220allows the liquid pump140to pump the liquid toward and away from the sensor110. The liquid tube220can extend around the sensor110, and the liquid can absorb heat from the sensor110as the liquid moves in the liquid tube220. For example, as shown inFIG. 3, the liquid tube220can wrap around the sensor110to provide convection cooling as the liquid moves in the liquid tube220.

FIG. 4shows a cross-sectional view of the sensor housing200. As inFIG. 3, the vehicle101includes the sensor110, the sensor manifold205, the nozzles210(and the respective openings215), the liquid tube220, the liquid pump140, and the air pump145.FIG. 4shows the sensor110installed in the sensor housing200when the computer105determines not to clean or cool the sensor110.

The vehicle101includes a liquid reservoir225. The liquid reservoir225stores the cleaning liquid. The liquid reservoir225can be connected to the liquid pump140via the liquid tube220. The liquid pump140can thus pump the liquid through the liquid tube220around the sensor110, into the liquid reservoir225, and out from the liquid reservoir225to an inlet of the liquid pump140. The liquid reservoir225can be disposed in the sensor housing200. Alternatively, the liquid reservoir225can be disposed in another part of the vehicle101, e.g., under a front hood, in a rear trunk, etc. The vehicle101can include more than one liquid reservoir225connected to the liquid tube220.

The sensor housing200includes an air tube230. The air tube230connects the air pump145to the sensor manifold205. The air tube230allows air to move from the air pump145to the sensor110through the nozzles210. The air tube230can be constructed of, e.g., a polymer, a metal, etc.

The sensor housing200includes a mixing valve235. The mixing valve235can have an air inlet240connected to the air tube230and a liquid inlet245connected to a mixing tube250, described below. The mixing valve235has an outlet255connected to the sensor manifold205. The mixing valve235allows air and liquid to move from the air tube230and the mixing tube235, respectively, into the sensor manifold205and to the nozzle210. When the computer105determines to clean the sensor110, the computer105actuates a diverter valve265to allow the liquid to move through a mixing tube250, mixing the liquid and the air in the mixing vale235into an air-liquid mixture and allowing the air-liquid mixture to move through the openings215in the nozzles210and onto the sensor110.

The sensor manifold205includes a fluid passage260. The fluid passage260connects the mixing valve235to the nozzles210. The fluid passage260allows the air or the air-liquid mixture to move from the mixing valve235to the nozzles210. The fluid passage260can be, e.g., a cavity formed in the sensor manifold205as shown inFIGS. 4-7, a set of tubes connecting the mixing valve235to each of the nozzles210, etc.

The sensor housing200includes a diverter valve265. The diverter valve265is connected to the liquid tube220and the mixing tube250. The diverter valve235includes a liquid outlet270and a mixing outlet275. The liquid outlet270allows the liquid to move through the liquid tube220to the sensor110. The mixing outlet275is connected to the mixing tube250. The mixing tube250is connected to the mixing valve235. The diverter valve265can be actuated by the computer105to selectively open the liquid outlet270and/or the mixing outlet275to allow the liquid to move through the liquid tube220and/or to allow the fluid to move through the mixing tube250and into the mixing valve235. As described below, the computer105can actuate the diverter valve265to open and/or close the liquid outlet270and/or the mixing outlet275.

As illustrated, the liquid outlet270and the mixing outlet275are closed when the respective portion of theFIGS. 5-7is solidly shaded, and the liquid outlet270and the mixing outlet275when the respective portion of the Figures is unshaded. For example, inFIG. 5, the mixing outlet275is closed (solidly shaded), and the liquid outlet270is open (not shaded). Furthermore, when one of the liquid tube220or the mixing tube250has no liquid flowing through, the respective tube220,250is represented as a dashed line; inFIG. 5, the mixing tube250has no liquid flow, and is represented with a dashed line. Because liquid moves in the liquid tube220, the liquid tube220is shown with a solid line. The flow of liquid is shown in thick arrows, and the flow of air is shown in thin arrows. For example, inFIG. 5, liquid (shown in thick arrows) flows only in the liquid tube220and air (shown in thin arrows) flows only in the fluid passage260. In another example, inFIG. 6, both liquid and air flow through the fluid passage260and through the nozzles210, shown as both thin arrows (representing air) and thick arrows (representing liquid) in the fluid passage260and the nozzles210.

FIG. 5illustrates an example actuation of the diverter valve265. In the example ofFIG. 5, the computer105instructs the diverter valve265to open the liquid outlet270and to close the mixing outlet275. The liquid pump140pumps the liquid through the liquid tube220around the sensor110, and the air pump145pumps air through the fluid passage260and the nozzles210onto the sensor110. The diverter valve265prevents liquid from moving to the mixing tube250and through the fluid passage and the nozzles and onto the sensor110. The computer105can actuate the diverter valve265in the manner shown inFIG. 5when, e.g., the computer105determines to cool the sensor110but not to clean the sensor110and the liquid is not necessary to clean the sensor110.

FIG. 6illustrates another example actuation of the diverter valve265. In the example ofFIG. 6, the computer105instructs the diverter valve265to close the liquid outlet270and to open the mixing outlet275. The liquid pump140pumps the liquid through the diverter valve265and the mixing tube250into the mixing valve235. The mixing valve235allows the air from the air pump145and the liquid from the liquid pump140to mix and to move through the fluid passage260. The air and liquid mixture then moves through the nozzles210through the openings215and onto the sensor110. The computer105can actuate the diverter valve265in the manner shown inFIG. 6when, e.g., the computer105determines to clean the sensor110but not to cool the sensor110and the liquid is not necessary to cool the sensor110.

FIG. 7illustrates another example actuation of the diverter valve265. In the example ofFIG. 7, the computer105instructs the diverter valve265to open the liquid outlet270and to open the mixing outlet275. The liquid pump140pumps the liquid through the diverter valve265, and the liquid moves through both the liquid tube220and the mixing tube250. The liquid moving through the liquid tube220cools the sensor110, and the liquid moving through the mixing tube250is mixed with the air in the mixing valve235and moves through the fluid passage260and the nozzles210though the openings215onto the sensor110. The computer105can actuate the diverter valve265in the manner shown inFIG. 7when, e.g., the computer105determines to both clean and cool the sensor110.

The computer105can determine an amount of occluding material on the sensor110. The computer105can actuate the sensor110to collect data115and determine the amount of occluding material on the sensor110from the collected data115. For example, the computer105can apply a conventional blur detection technique to the data115to determine if an image from the data115is blurred. The computer105can measure a pixel-to-pixel contrast of the image from the data115and determine a blurred pixel when the pixel, when convolved with a predetermined Laplacian kernel, has a statistical variance σ2(i.e., the square of the standard deviation σ as used in statistical analysis) greater than a predetermined threshold. Alternatively, the computer105can use a different blur detection technique to determine a number of blurred pixels. The computer105can determine the amount of occluding material as a fraction of the number of blurred pixels (determined based on a blur detection technique such as described above) to the total number of pixels in the image from the data115.

As another example, the computer105can use a conventional light attenuation technique on the image from the data115to determine an amount of occluding material on the sensor110. The computer105can detect an attenuation of incoming light, i.e., an amount of light lost when traveling through the occluding material to the sensor110, and a scattering of stray light towards the sensor110by the occluding material on the sensor110. The computer can apply conventional natural image statistics techniques (e.g., Bayesian de-noising) to the image to determine pixels where a scene radiance is reduced by the occluding material and pixels where the occluding material contributes radiance to the sensor110by scattering the light from another direction. The computer105can determine a number of pixels in the image from the data115where the attenuation of the light is reduced, and the computer105can determine the amount of occluding material as a fraction of the number of pixels with reduced attenuation to the total number of pixels in the image from the data115.

The computer105can use a conventional image comparison technique to determine the amount of occluding material on the sensor110. The computer105can compare the image from the data115to an estimated background image based on, e.g., data115from another sensor110, data115from the server130, etc. The computer105can determine a number of pixels that differ from the estimated background image, i.e., the pixel “differs” from the estimated background image when a difference between the red-green-blue (RGB) or grayscale values of the pixel from the image from the data115and the RGB or grayscale values of the corresponding pixel from the estimated background image is greater than a difference threshold. The difference threshold can be a predetermined value stored in the data store106and determined by, e.g., empirical testing, known statistical standards, etc. The computer105can determine the amount of occluding material as a fraction of the number of pixels that differ from the estimated background image to the total number of pixels in the image from the data115.

The computer105can use a conventional stereovision image comparison technique to determine the amount of occluding material on the sensor110. The sensor110can be a stereovision image sensor110, i.e., the sensor110can have two lenses separated by a fixed distance and captures two images simultaneously when collecting data115. The computer105can compare the two simultaneously collected images and determine a number of pixels that differ between the two images, e.g., as described above for the image comparison technique. The computer105can determine the amount of occluding material as a fraction of the number of pixels that differ between the two images to the total number of pixels in the one of the images from the data115.

Based on one or more of the above-described techniques, the computer105can determine the amount of occluding material on the sensor110. A measurement of an amount of occluding material can be provided as a number between and including 0 and 1, representing a fraction of a number of pixels in an image collected by the sensor110that are obstructed by the occluding material. When the amount of occluding material is 0, the sensor110collects data115with no pixels obstructed by occluding material. When the amount of occluding material is 1, all of the pixels in the data115are obstructed by occluding material. The techniques described above illustrate one of a plurality of techniques for identifying pixels that are obstructed by occluding material, and upon identifying the pixels that are obstructed, the computer105can determine a fraction of the obstructed pixels to the total number of pixels, resulting in a number between 0 and 1, inclusive. That number is one example of the amount of occluding material on the sensor110.

The computer105can determine a temperature of the sensor110. The sensor110can include a temperature sensor110(e.g., a thermocouple, a thermistor, etc.) that can collect data115about the temperature of the sensor110. The temperature sensor110, while not shown in the Figures, can be fixed to the sensor110in the sensor housing200. The computer105can, based on the temperature data115, actuate the liquid pump140, the air pump145, and the diverter valve265.

The computer105can compare the amount of occluding material to an occluding material threshold. The occluding material threshold can be a predetermined value, e.g., between and including 0 and 1, stored in the data store106and/or the server130. The occluding material threshold can be based on an amount of occluding material beyond which the sensor110operation is reduced more than the reduction of sensor110operation based on the temperature threshold (described below). For example, the occluding material threshold can be a fraction of a total number of pixels from an image from collected data115from the sensor110beyond which the computer105determines that the sensor110is no longer collecting enough data115(i.e., enough pixels are obstructed) to operate the components120. The occluding material threshold can be determined based on, e.g., empirical tests of sensor110operation, manufacturer specifications, etc. The occluding material threshold can be, e.g., 0.7, i.e., 70% of the pixels in an image from the data115are obstructed by occluding material.

The computer105can compare the temperature to a temperature threshold. The temperature threshold can be a predetermined value stored in the data store106and/or the server130. The temperature threshold can be based on a temperature beyond which operation of the sensor can be reduced, e.g., 105° C. The temperature threshold can be determined based on, e.g., empirical tests of sensor110operation, manufacturer specifications, etc.

Based on an amount of occluding material and the temperature, the computer105can the computer105can actuate the liquid pump140and the air pump145to specified respective duty cycles. For example, the computer105can actuate the liquid pump140and the air pump145in one of four modes based on the temperature threshold and the occluding matter threshold. Each of the four modes specifies a liquid pump140duty cycle for the liquid pump140and an air pump145duty cycle for the air pump145.

The computer105can actuate the diverter valve, the liquid pump140, and the air pump145in a first mode when the amount of occluding matter on the sensor110is below the occluding matter threshold (as described above) and the temperature of the sensor110is below the temperature threshold (as described above). In the first mode, the computer105determines not to immediately clean or cool the sensor110, and can operate the diverter valve265such that the liquid outlet270is open and the mixing outlet275is closed, e.g., as shown inFIG. 5. The computer105can determine to clean the sensor110and can open the mixing outlet275to allow liquid to mix with the air and spray through the nozzles210onto the sensor110, e.g., as shown inFIG. 7. When the computer105determines to stop cleaning the sensor110, the computer105can instruct the mixing outlet275to close. The computer105can specify a first liquid pump140duty cycle and a first air pump145duty cycle to allow cleaning the sensor110upon request by the vehicle101user.

The computer105can actuate the diverter valve265, the liquid pump140, and the air pump145in a second mode when the amount of occluding matter on the sensor110is below the occluding matter threshold and the temperature of the sensor110is above the temperature threshold. In the second mode, the computer105can determine that cooling the sensor110has priority over cleaning the sensor110. The computer105can close the mixing outlet275, open the liquid outlet270, and increase the duty cycle of the liquid pump140to a second liquid pump140duty cycle to increase cooling of the sensor110with liquid convection cooling, as shown inFIG. 5. The computer105can actuate the air pump145to a second air pump145duty cycle to increase air flow further cool the sensor110with air convection cooling. If the computer105receives a request to clean the sensor110from the vehicle101user, the computer105can open the mixing outlet275to allow liquid to mix with the air and spray through the nozzles onto the sensor110, e.g., as shown inFIG. 7. When the computer105no longer receives the request, the computer105can instruct the mixing outlet275to close. That is, the second liquid pump140duty cycle is greater than the first liquid pump140duty cycle to accommodate the increased liquid flow for cleaning of the sensor110upon request by the vehicle101user and for cooling the sensor110. The computer105can deactivate the sensor110upon determining that the temperature of the sensor110is above the temperature threshold.

The computer105can actuate the diverter valve265, the liquid pump140, and the air pump145in a third mode when the amount of occluding matter on the sensor110is above the occluding matter threshold and the temperature of the sensor110is above the temperature threshold. In the third mode, the computer105can determine to both clean and cool the sensor110and that both cooling and cleaning the sensor110should not be performed simultaneously. The computer105can deactivate the sensor110and actuate one or more vehicle components120to move the vehicle101away from a roadway (e.g., to a roadway shoulder) and stop the vehicle101. The computer105can then actuate the liquid pump140to a third liquid pump140duty cycle and the air pump145to a third air pump145duty cycle. The computer105can actuate the diverter valve265to close the mixing outlet275and open the liquid outlet270, allowing the liquid to move through the liquid tube220and cool the sensor110, as shown inFIG. 5. When the computer105determines that the temperature of the sensor110is below the temperature threshold, the computer105can actuate the diverter valve265to open the mixing outlet275and close the liquid outlet270, allowing the liquid to move through the mixing tube250to mix with the air and spray onto the sensor110, cleaning the sensor110as shown inFIG. 6. When the computer105determines that the amount of occluding material on the sensor110is below the occluding material threshold, the computer105can activate the sensor110and actuate one or more vehicle components120to move the vehicle101.

The computer105can actuate the diverter valve265, the liquid pump140, and the air pump145in a fourth mode when the amount of occluding matter on the sensor110is above the occluding matter threshold and the temperature of the sensor110is below the temperature threshold. In the fourth mode, the computer105can determine that cleaning the sensor110has priority over cooling the sensor110. The computer105can actuate the liquid pump140to a fourth liquid pump140duty cycle and the air pump145to a fourth air pump145duty cycle. The computer105can actuate the diverter valve265to open the mixing outlet275and to close the liquid outlet270, as shown inFIG. 6, to clean the sensor110.

Rules governing actuation of the diverter valve265, liquid pump140, and the air pump145can be included as a look-up table stored in the data store106and/or the server130accessible by the computer105via the network125. An example table is shown below in Table 1.

FIG. 8illustrates an example process800for cleaning and cooling a sensor110in a vehicle101. The process800begins in a block805, in which the computer105determines an amount of occluding material on a sensor110. As described above, the computer105can use a conventional image processing technique to determine a number of pixels in an image from the data115obstructed by occluding material to determine the amount of occluding material on the sensor110.

Next, in a block810, the computer105determines a temperature of the sensor110. The sensor housing can include a temperature sensor110that can collect temperature data115from the sensor110. The computer105can determine the temperature of the sensor110from the temperature data115.

Next, in a block815, the computer105compares the amount of occluding material to an occluding material threshold and the temperature to a temperature threshold. As described above, based on whether one or both of the amount of occluding material and the temperature exceeds their respective thresholds, the computer105can actuate components120in a specified manner to cool and clean the sensor110.

Next, in a block820, the computer105actuates the diverter valve265based on the amount of occluding material and the temperature. For example, when the amount of occluding material is above the occluding material threshold and the temperature is below the temperature threshold, the computer105can actuate the diverter valve265to open the mixing outlet275and to close the liquid outlet270, as shown inFIG. 6, to clean the sensor110.

Next, in a block825, the computer105actuates the liquid pump140to a specified duty cycle. As described above, the computer105can determine the liquid pump140duty cycle based on the amount of occluding material and the temperature. For example, when the temperature is above the temperature threshold and the amount of occluding material is below the occluding material threshold, the computer105can actuate the liquid pump140to a liquid pump140duty cycle of 60%, as shown in Table 4 above.

Next, in a block830, the computer105actuates the air pump145to a specified duty cycle. As described above, the computer105can determine the air pump145duty cycle based on the amount of occluding material and the temperature. For example, when the temperature is above the temperature threshold and the amount of occluding material is below the occluding material threshold the computer105can actuate the air pump145to an air pump145duty cycle of 50%, as shown in Table 4 above.

Next, in a block835, the computer105determines whether to continue the process800. For example, if the temperature of the sensor110falls below the temperature threshold, and the vehicle101is still moving to a destination, the computer105can determine to continue the process800to determine whether to clean the sensor110. If the computer105determines to continue, the process800returns to the block805to determine an amount of occluding material on the sensor110. Otherwise, the process800ends.

With regard to the media, processes, systems, methods, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. For example, in the process800, one or more of the steps could be omitted, or the steps could be executed in a different order than shown inFIG. 8. In other words, the descriptions of systems and/or processes herein are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the disclosed subject matter.

The article “a” modifying a noun should be understood as meaning one or more unless stated otherwise, or context requires otherwise. The phrase “based on” encompasses being partly or entirely based on.