Method and device for operating an external sensor of a vehicle

Abstract

The invention relates to a method for operating an external sensor (3) of a vehicle (1), particularly under winter conditions, with a heating mode (100) for heating the external sensor (3), in which, during heating mode (100), the external sensor (3) itself forms a heating device (5) such that the external sensor (3) is heated by the heat (102) generated during operation of the external sensor (3), wherein the heat is generated by increasing an instantaneous processor clock rate to a predetermined heating clock rate, which is higher than a basic clock rate of the processor.

Description

The invention relates to a method and a device for operating an external sensor of a vehicle. External sensors, such as cameras, radar, ultrasonic sensors, lidar systems, or similar devices, mounted on the outside of a vehicle are common. In winter conditions, these sensors can ice over or become dirty from snow, rain, or dew. Therefore, such external sensors typically include heating elements to prevent these problems. From DE 10 2023 001 756 A1, a method for controlling a heating device of an external sensor of a vehicle is known. In this method, in which the heating device is operated in an energy-efficient manner, the heating device is only heated when a surface of the external sensor is covered with snow and / or ice. German patent application DE 10 2023 205 250 A1 describes a radar device that uses its own waste heat to keep the front cover free of ice and snow. A heat-conducting element directs the heat generated by the radar electronics during operation into the cover. This cover is made of a thermally conductive plastic that distributes the heat evenly, thus ensuring effective melting. The invention is based on the objective of providing an improved method and an improved device for operating an external sensor of a vehicle. The first problem is solved according to the invention by a method for operating an external sensor of a vehicle with the features of claim 1. The second problem is solved according to the invention by a device for operating an external sensor of a vehicle with the features of claim 8. Advantageous embodiments of the invention are the subject of the dependent claims. The inventive method for operating an external sensor of a vehicle, particularly under winter conditions, provides for a heating operation to heat the external sensor, wherein in the heating operation the external sensor itself forms a heating device such that the external sensor is heated by the heat generated during the operation of the external sensor. The advantages achieved with the invention lie particularly in the fact that an additional heating device can be omitted. This saves both installation space and costs. In other words, the heating device (also called a heating element) is / is formed by the outdoor sensor itself. For heating purposes, the clock rate of a sensor electronics component, such as a microprocessor, control unit, electronic circuit, or the like, is increased from a base clock rate to a heating clock rate. The microprocessor, preferably installed in the outdoor sensor housing, dissipates heat, thus warming the housing and melting any ice buildup, as well as evaporating any condensation on the sensor lens. Preferably, the microprocessor housing has a thermal connection to the sensor housing, so that the heat from the microprocessor is transferred directly to the housing and thus also to the sensor lens. Additionally, continuous monitoring of the sensor function and / or sensor operation can be performed, whereby if no improvement in the sensor function / sensor operation occurs after a specified time, the processor clock rate can be reduced back to the base clock rate. If no improvement is detected, the sensor electronics can transmit a signal to an actuator. For example, a signal prompting a user to manually clean the outdoor sensor can be displayed on a screen. Alternatively, a signal can be sent to a cleaning unit, particularly a compressed air cleaning unit and / or a water cleaning unit, for automatic cleaning of the outdoor sensor. Continuous monitoring of the external sensor can be performed using its sensor data, such as camera images, radar images, or similar data. For example, an improvement in camera performance can be determined by an increase in the brightness of the external sensor's images. For radar or lidar sensors, an improvement in performance can be detected by reducing near-field reflections. For example, the reduction of near-field reflections can be detected by analyzing reflected laser beams. Additionally, it may be stipulated that the external sensor is checked after or during each vehicle start, in particular for availability and / or degradation. Additionally, it may be possible to identify winter conditions using further sensor data, for example from a temperature sensor, and / or using recorded weather data, and to automatically activate the heating operation of the outdoor sensor as described above. Exemplary embodiments of the invention are explained in more detail below with reference to drawings. Figure 1 schematically shows an embodiment of a device for operating an outdoor sensor, and Figure 2 schematically shows an example of an outdoor sensor with limited functionality. Corresponding parts are marked with the same reference symbols in all figures. Fig. 1 shows a vehicle 1 with an embodiment of a device 2 according to the invention for operating an external sensor 3. The external sensor 3 is located and mounted on the outside of the vehicle 1. In heating mode 100, the external sensor 3 itself forms a heating element 5. The external sensor 3 is heated by the heat generated by the microprocessor during its operation. The device 2 according to the invention is particularly advantageous in winter conditions. The external sensor 3 is designed in particular as a camera, radar, lidar and / or ultrasonic sensor and is mounted on the outside of the vehicle 1. In winter conditions, the outdoor sensor 3 may be covered with ice, snow (shown in Fig. 2), dew, or similar substances. These conditions can impair the function of the outdoor sensor 3. The method according to the invention enables the reliable operation of the outdoor sensor 3 even in winter conditions and without additional heating. The external sensor 3 includes sensor electronics 7, in particular a processor 7.1. The processor 7.1 generally operates at a predetermined base clock rate, which is necessary for the operation of the external sensor 3. If a functional limitation of the external sensor 3 is detected by means of the sensor electronics 7, the heating operation 100 is activated by means of the sensor electronics 7, in which the external sensor 3 is heated by its own heat 102 or can be heated. In heating mode 100, to remove, for example, snow 104, dew, or ice from the external sensor 3, the base clock rate at which the processor 7.1 operates is increased to a predefined heating clock rate. This higher clock rate of the processor 7.1, which exceeds the base clock rate, generates its own heat 102, thus heating the external sensor 3. The higher temperature of the external sensor 3 ensures its cleaning, in particular by thawing an outer layer of weather. For example, the external sensor 3, especially a sensor lens (not shown in detail), can be easily freed from a layer of ice, dew, snow 104, or the like by the generated own heat 102. A malfunction of the external sensor 3 can be detected, for example, by means of its own sensor electronics 7 and / or based on other sensor values ​​and / or vehicle information. For example, a malfunction can be detected by monitoring the signal intensity, the signal-to-noise ratio, and / or by comparing it with historical data from the external sensor 3 itself. The sensor electronics 7 can also perform a self-diagnosis to detect a malfunction of the external sensor 3. For example, the self-diagnosis can detect whether there is a layer of snow, ice, or dew on the external sensor 3, or similar, and whether the outside temperature is simultaneously below 10 degrees. If this is the case, the heating mode 100 of the external sensor 3 is activated, and the base clock rate of the processor 7.1 is increased to the specified heating clock rate to generate the necessary heat 102. Furthermore, it may be provided that the malfunction is detected in its nature, in particular whether the malfunction is caused by snow 104, ice, dew, etc. For this purpose, additional sensor data, for example from a temperature sensor 9 and / or a navigation system, from a weather service, from a central control room or the like, can be recorded and transmitted to the sensor electronics 7 for evaluation. Furthermore, the operation of the external sensor 3 can be checked each time the vehicle 1 is started. In particular, the external sensor 3 can be checked for degradation, specifically for sufficiently reliable operation, faulty operation, or deteriorated operation, using its own sensor data, additional sensor data from other sensors, vehicle information, driving information, weather data, navigation data, or the like, each time the vehicle is started. For example, after a parking period, the outside temperature can first be checked using vehicle information and / or sensor values, in particular with at least one temperature sensor 9, weather data from a navigation system, camera data from a camera, or the like. If the outside temperature falls below a predetermined temperature, in particular below 10 degrees, the outside sensor 3 is activated and a self-diagnosis is performed by the sensor electronics 7 to detect a possible malfunction of the outside sensor 3. If a malfunction is detected, the heating operation 100 of the outside sensor 3 is then activated and the current processor clock rate is increased to a predetermined heating clock rate, in particular to a maximum clock rate. Additionally, while heating operation 100 is activated and thus processor 7.1 is active as heating device 5, a continuous check of the sensor function can be carried out, whereby if no improvement in the sensor function / sensor operation occurs after a specified time, the processor clock rate can be reduced back to the base clock rate. Continuous monitoring of the external sensor 3 is primarily achieved by evaluating the sensor data from that same external sensor 3. For cameras used as external sensor 3, an improvement in function can be observed, for example, through brighter images. For radar or lidar sensors used as external sensor 3, an improvement in operation can be detected by reducing near-field reflections. For example, the reduction of near-field reflections is detected by analyzing reflected laser beams. If no improvement in the function of the external sensor 3 occurs after a specified time, especially in the case of incorrectly detected dirt or a heavy layer of snow, a signal for manual and / or automatic cleaning of the external sensor 3 is sent to an actuator. Automatic cleaning is carried out, for example, by a cleaning unit 11, which uses compressed air and / or water to clean the external sensor 3 and thus improves the function of the respective external sensor 3. Figure 2 schematically depicts an outdoor sensor 3 whose function is impaired by winter conditions, particularly by snow 104. This snow 104 is determined, as described with reference to Figure 1, by means of self-diagnosis and / or other sensor data, so that the heating operation 100 of the outdoor sensor 3 is activated in order to free the outdoor sensor 3 from this snow 104 by means of the resulting heat 102 of the processor 7.1 of the sensor electronics 7.

Claims

Method for operating an external sensor (3) of a vehicle (1) with a heating mode (100) for heating the external sensor (3), wherein in heating mode (100) the external sensor (3) itself forms a heating device (5) such that this external sensor (3) is heated by the heat (102) generated during the operation of the external sensor (3), characterized in that the external sensor (3) comprises a processor (7.1) and is heated by the heat (102) of the processor (7.1), wherein the heat (102) is generated by increasing an instantaneous processor clock rate of the processor (7.1) to a predetermined heating clock rate, which is higher than a basic clock rate of the processor (7.1). Method according to one of the preceding claims, characterized in that the self-heating (102) is only generated when a cold weather condition is detected based on sensor values ​​and / or vehicle information and / or a malfunction of the external sensor (3) is detected by the external sensor (3) itself. Method according to one of the preceding claims, characterized in that the operation of the external sensor (3) is continuously monitored, wherein a signal for manual and / or automatic cleaning of the external sensor (3) is additionally generated by means of sensor electronics (7). Method according to claim 3, characterized in that the signal from the sensor electronics (7) is sent to a cleaning unit (11), in particular a compressed air cleaning unit or a water cleaning unit, which is automatically activated. Method according to claim 3 or 4, characterized in that the operation of the external sensor (3) is monitored by means of camera images, a brightening of camera images, an increase and / or reduction of the number of near reflections. Method according to one of the preceding claims, characterized in that the operation of the external sensor (3) is checked for degradation at each vehicle start. Method according to one of the preceding claims, characterized in that further sensor data from at least one temperature sensor (9) and / or weather data are recorded and taken into account when monitoring the operation of the outdoor sensor (3). Device (2) for operating an external sensor (3) of a vehicle (1) according to the method of one of the preceding claims, wherein the device (2) comprises an external sensor (3) which is arranged on the outside of the vehicle (1), characterized in that the external sensor (3) itself forms a heating device (5) in heating mode (100) such that this external sensor (3) can be heated or is heated by the heat (102) generated by its own operation.

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