JP7496017B2 - Sensor Systems - Google Patents

Description

The present invention relates to a sensor system mounted on a vehicle.

To provide driving assistance to a vehicle, a sensor unit for detecting information outside the vehicle is mounted on the vehicle body. Patent Document 1 discloses a radar as such a sensor unit. The radar is disposed inside a lamp chamber of a lamp device that illuminates the outside of the vehicle. That is, the radar is covered by a cover that defines the lamp chamber and allows the passage of illumination light. The cover forms part of the exterior surface of the vehicle and also allows the passage of detection light for the radar to detect external information.

The term "driving assistance" as used in this specification refers to a control process that at least partially performs at least one of the following driving operations (steering, acceleration, deceleration, etc.), monitoring of the driving environment, and backup of driving operations. In other words, it includes everything from partial driving assistance such as collision mitigation braking functions and lane keep assist functions to fully automated driving operations.

JP 2007-106199 A

The object of the present invention is to suppress the deterioration of the information detection capability of a sensor unit covered by a cover that forms part of the exterior surface of a vehicle.

A first aspect of the present invention to achieve the above object is a sensor system mounted on a vehicle, comprising: a sensor unit that detects information outside the vehicle using light;
a cover forming a part of an exterior surface of the vehicle so as to cover the sensor unit and allowing the light to pass through;
a pH sensor having a detection surface disposed adjacent to the cover;
It is equipped with:

The change in the pH value on the detection surface of the pH sensor is most likely caused by a foreign object adhering to the detection surface. In this case, there is a high possibility that a foreign object is also adhering to the cover. Therefore, the processor can determine that a foreign object is adhering to the cover based on this change in the pH value.

If a foreign object adheres to a part of the cover located on the path of light used by the sensor unit to detect information, this can hinder the sensor unit from detecting information about the outside of the vehicle. However, the pH sensor arranged as described above detects the adhesion of such foreign objects, and appropriate action can be taken according to the detection results. This makes it possible to suppress a decrease in the information detection ability of the sensor unit covered by the cover that forms part of the exterior surface of the vehicle.

The sensor system according to the first aspect can be configured as follows.
A nozzle capable of ejecting liquid;
a processor that causes the nozzle to eject the liquid toward the cover based on a signal output from the pH sensor;
It is equipped with:

This configuration allows the process of removing foreign matter adhering to the cover to be automated. This improves the effectiveness of preventing a decrease in the information detection capability of the sensor unit covered by the cover that forms part of the exterior surface of the vehicle.

The sensor system according to the first aspect can be configured as follows.
The detection surface is immersed in a liquid whose pH value is controlled.

In other words, a pH sensor that uses the glass electrode method, which is widely used as a so-called wet type, can be used.

A first aspect of the present invention to achieve the above object is a sensor system mounted on a vehicle, comprising: a sensor unit that detects information outside the vehicle using light;
a cover forming a part of an exterior surface of the vehicle so as to cover the sensor unit and allowing the light to pass through;
a strain gauge having a detection surface disposed adjacent to the cover;
It is equipped with:

The change in the load value on the detection surface of the strain gauge is most likely caused by a foreign object adhering to the detection surface. In this case, there is a high possibility that a foreign object is also adhering to the cover. Therefore, the processor can determine that a foreign object is adhering to the cover based on this change in the load value.

If a foreign object adheres to a part of the cover located on the path of light used by the sensor unit to detect information, this can hinder the sensor unit from detecting information about the outside of the vehicle. However, the attachment of such foreign objects is detected by the strain gauges arranged as described above, and appropriate processing can be taken according to the detection results. This makes it possible to suppress a decrease in the information detection ability of the sensor unit covered by the cover that forms part of the exterior surface of the vehicle.

The sensor system according to the second aspect can be configured as follows.
A nozzle capable of ejecting liquid;
a processor that causes the nozzle to eject the liquid toward the cover based on a signal output from the strain gauge;
It is equipped with:

This configuration allows the process of removing foreign matter adhering to the cover to be automated. This improves the effectiveness of preventing a decrease in the information detection capability of the sensor unit covered by the cover that forms part of the exterior surface of the vehicle.

The sensor system according to each of the above aspects can be configured as follows.
An ultrasonic actuator is provided for applying ultrasonic waves to the liquid.

This configuration provides a so-called ultrasonic cleaning effect with the liquid sprayed from the nozzle, further facilitating the peeling and removal of foreign matter adhering to the cover.

The sensor system according to each of the above aspects can be configured as follows.
The device is provided with a flow path having a drainage structure that utilizes gravity,
The detection surface is disposed within the flow path.

Liquid that flows down the surface of a cover with foreign matter adhering thereto is highly likely to contain components of the foreign matter. Therefore, when the liquid is received in the flow path, it changes the pH value of the detection surface of a pH sensor disposed in the flow path. This makes it possible to detect the adhesion of foreign matter to the cover. The detection surface of the pH sensor can be positioned anywhere along the path of movement of the liquid due to gravity. This allows for greater freedom in the placement of the pH sensor.

Liquid flowing down the surface of a cover with foreign matter adhering thereto is highly likely to contain at least a portion of the foreign matter. Therefore, when the liquid is received in the flow path, it causes a greater change in the load applied to the detection surface of the strain gauge than when liquid without the foreign matter is received. This makes it possible to detect the adhesion of foreign matter to the cover. The detection surface of the strain gauge can be placed anywhere along the path of movement of the liquid due to gravity. This allows for greater freedom in placement of the strain gauge.

The sensor system according to each of the above aspects can be configured as follows.
A lamp unit is provided for emitting illumination light to the outside of the vehicle,
The cover allows the illumination light to pass through.

Because lamp units have the function of supplying illumination light to the outside of the vehicle, they are generally placed in locations on the vehicle where there are few obstructions. By also placing the sensor unit in such a location, information about the outside of the vehicle can be obtained efficiently.

The term "light" as used in this specification refers to electromagnetic waves of any wavelength, including not only visible light, but also ultraviolet light, infrared light, microwaves, and millimeter waves.

The term "sensor unit" as used in this specification refers to a component unit that has the desired information detection function and can be distributed independently.

As used herein, the term "lamp unit" refers to a component unit that has the desired lighting function and can be sold separately.

1 illustrates an example of a configuration of a sensor system according to a first embodiment. 2 illustrates an example of the appearance of a vehicle in which the sensor system of FIG. 1 is mounted. 2 illustrates an example of the operation of a processor in the sensor system of FIG. 1 . 2 illustrates an example of a flow path configuration in the sensor system of FIG. 1 . 1 illustrates a configuration of a sensor system according to a second embodiment. 6 illustrates the operation of a processor in the sensor system of FIG. 5 . 6 illustrates an example of a flow path configuration in the sensor system of FIG. 5 .

The following describes in detail an example embodiment with reference to the accompanying drawings. The scale of each drawing used in the following description has been appropriately changed so that each component is of a recognizable size.

In the accompanying drawings, arrow F indicates the forward direction of the illustrated structure. Arrow B indicates the rearward direction of the illustrated structure. Arrow U indicates the upward direction of the illustrated structure. Arrow D indicates the downward direction of the illustrated structure. Arrow L indicates the leftward direction of the illustrated structure. Arrow R indicates the rightward direction of the illustrated structure. In the following explanation, "left" and "right" refer to the left and right directions as seen from the driver's seat.

Figure 1 illustrates an example of the configuration of a sensor system 1 according to the first embodiment. The sensor system 1 is mounted on a vehicle 100 shown in Figure 2. The shape of the body of the vehicle 100 is merely an example.

The sensor system 1 includes a housing 11 and a cover 12. The housing 11, together with the cover 12, defines a storage chamber 13.

The sensor system 1 includes a LiDAR sensor unit 14. The LiDAR sensor unit 14 is disposed in a housing chamber 13. The cover 12 forms a part of the exterior surface of the vehicle 100 so as to cover the LiDAR sensor unit 14.

The LiDAR sensor unit 14 is configured to emit detection light toward a detection area outside the vehicle 100, and detect return light (not shown) that is the result of the detection light being reflected by an object present within the detection area. For example, infrared light with a wavelength of 905 nm can be used as the detection light.

The LiDAR sensor unit 14 can obtain the distance to an object associated with the returning light, for example, based on the time from when detection light is emitted in a certain direction to when the returning light is detected. Furthermore, by accumulating such distance data in association with the detection position, information related to the shape of the object associated with the returning light can be obtained. In addition or instead, information related to attributes such as the material of the object associated with the returning light can be obtained based on the difference in the waveforms of the emitted light and the returning light. In other words, the LiDAR sensor unit 14 is a device that uses light to detect information outside the vehicle 100.

The detection light and the return light pass through the light passing area 12a in the cover 12. In other words, the cover 12 is made of a material that allows at least the detection light and the return light to pass through.

The sensor system 1 includes a pH sensor 15. The pH sensor 15 is disposed on the cover 12. More specifically, the pH sensor 15 is disposed at a position that avoids the light passing area 12a of the cover 12. Being disposed on the cover 12 is an example of being disposed adjacent to the cover.

The pH sensor 15 has a detection surface 15a. The pH sensor 15 is configured to measure the pH value of the detection surface 15a and output a pH signal S11 corresponding to the measured pH value. The pH sensor 15 measures the pH value of the detection surface 15a by a method called a dry method. That is, the pH sensor 15 has a platinum wire and a silver/silver chloride wire. The potential difference generated between the platinum wire and the silver/silver chloride wire based on the Nernst response on the platinum wire changes according to the pH value of the detection surface 15a. The pH signal S11 changes in response to the potential difference.

The sensor system 1 includes a control device 16. The control device 16 includes an input interface 161 and a processor 162. The control device 16 may be disposed within the accommodation compartment 13, or may be supported on the housing 11 outside the accommodation compartment 13. Alternatively, the control device 16 may be disposed at an appropriate position in the vehicle 100 separate from the housing 11.

The input interface 161 receives the pH signal S11 output from the pH sensor 15. The processor 162 is configured to detect foreign matter adhering to the cover 12 based on the pH signal S11. Examples of foreign matter include raindrops, snowflakes, sludge, and dead insects. The input interface 161 may include a signal processing circuit that converts the pH signal S11 into a form suitable for processing by the processor 162 as necessary.

Figure 3 shows an example of the flow of processing performed by the processor 162. The processor 162 first acquires a pH reference value (STEP 11). Specifically, the processor 162 causes the input interface 161 to accept a pH signal S11 from the pH sensor 15 at a predetermined timing, thereby acquiring the pH value of the detection surface 15a at the predetermined timing as a reference value. An example of the predetermined timing is when the sensor system 1 is started up.

As shown in FIG. 1, the control device 16 includes a storage 163. The storage 163 can be realized by an appropriate rewritable semiconductor memory. The processor 162 stores data corresponding to the pH value as the reference value obtained as described above in the storage 163.

Next, the processor 162 causes the input interface 161 to receive the pH signal S11 from the pH sensor 15 at a predetermined time interval. That is, the processor 162 acquires the measurement value of the pH sensor 15 at a predetermined time interval (STEP 12). The predetermined time interval is, for example, 100 milliseconds.

Next, the processor 162 compares the pH measurement value of the detection surface 15a of the pH sensor 15 obtained in STEP 12 with the pH reference value stored in the storage 163 in STEP 11. The processor 162 determines whether the difference between the measurement value and the reference value is equal to or greater than a predetermined value (STEP 13).

The change in pH value on the detection surface 15a of the pH sensor 15 that occurs after the reference value is obtained is most likely caused by a foreign object adhering to the detection surface 15a. In this case, there is a high possibility that a foreign object is also adhering to the cover 12. Therefore, if the difference between the measured value and the reference value for the pH value on the detection surface 15a is equal to or greater than a predetermined value (YES in STEP 13), the processor 162 determines that a foreign object is adhering to the cover 12 and generates a detection signal S12 (STEP 14).

If the difference between the measured pH value on the detection surface 15a and the reference value is less than the predetermined value (NO in STEP 13), the processor 162 determines that no foreign matter is attached to the cover 12, and the process returns to STEP 12.

As shown in FIG. 1, the control device 16 includes an output interface 164. The processor 162 causes the output interface 164 to output a detection signal S12. The detection signal S12 can be transmitted to another control device in the vehicle 100. For example, the other control device can notify an occupant of the vehicle 100 that a foreign object is attached to the cover 12 based on the detection signal S12. The notification can be made through at least one of a visual notification, an auditory notification, and a tactile notification.

Occupants who receive the notification can take appropriate action. For example, the sensor system 1 can be equipped with a nozzle 17 that sprays liquid toward the cover 12. Examples of liquid include water, hot water, and cleaning liquid. The occupant can operate the nozzle 17 to spray liquid. This can remove foreign matter adhering to the cover 12.

If a foreign object adheres to the light passage area 12a located on the path of the detection light and return light of the LiDAR sensor unit 14, it may hinder the LiDAR sensor unit 14 from detecting information outside the vehicle 100. However, the pH sensor 15 configured as described above can detect the adhesion of such foreign objects, and appropriate processing can be taken according to the detection results. This makes it possible to suppress a decrease in the information detection ability of the LiDAR sensor unit 14 covered by the cover 12 that forms part of the exterior surface of the vehicle 100.

Once the foreign matter removal process has been performed, the process returns to STEP 11. That is, the pH value of the detection surface 15a of the pH sensor 15 at this point is acquired and used as a new reference value for the subsequent process. In other words, the time after the nozzle 17 is operated can be an example of a predetermined timing for acquiring the pH reference value.

As shown in FIG. 1, the detection signal S12 generated by the processor 162 can be used to operate the nozzle 17 described above. That is, when a foreign object adhering to the cover 12 is detected, the processor 162 can cause the nozzle 17 to spray liquid toward the cover 12.

This configuration allows the process of removing foreign matter adhering to the cover 12 to be automated. This enhances the effect of suppressing the deterioration of the information detection capability of the LiDAR sensor unit 14 covered by the cover 12 that forms part of the exterior surface of the vehicle 100.

As shown in FIG. 1, the nozzle 17 may include an ultrasonic actuator 171. The ultrasonic actuator 171 is a device that vibrates at a frequency in the ultrasonic band and excites a natural vibration in the liquid that is sprayed from the nozzle 17 toward the cover 12. In this case, the processor 162 outputs a control signal S13 to the output interface 164, which operates the ultrasonic actuator 171 when the nozzle 17 sprays the liquid.

With this configuration, the liquid sprayed from the nozzle 17 produces a so-called ultrasonic cleaning effect, further facilitating the removal of foreign matter adhering to the cover 12.

The location of the pH sensor 15 is not limited to on the cover 12. If it is possible to detect foreign matter attached to the cover 12, it may be placed in a position adjacent to the cover 12 on the housing 11 or the body of the vehicle 100.

As shown in FIG. 1, the sensor system 1 may include a flow path 18. The flow path 18 is disposed below the light passing area 12a of the cover 12 and adjacent to the cover 12 to receive liquid that passes through at least the light passing area 12a and flows down onto the cover 12. Examples of such liquid include raindrops, melted snowflakes, dirty water splashed up from the road surface by the vehicle or another vehicle, and liquid sprayed from the nozzle 17 onto the cover 12. The flow path 18 may be formed as part of the housing 11 or the cover 12.

The flow path 18 has a drainage structure that utilizes gravity. In the example shown in FIG. 1, the second end 18b of the flow path 18 is located lower than the first end 18a. The second end 18b is open to the outside. Therefore, the liquid received by the flow path 18 flows through the flow path 18 toward the second end 18b and is discharged from the second end 18b.

In this case, the detection surface 15a of the pH sensor 15 can be disposed within the flow path 18. Therefore, the pH sensor 15 is disposed adjacent to the cover 12.

Liquid that flows down the surface of the cover 12 to which foreign matter is attached is highly likely to contain components of the foreign matter. Therefore, when the liquid is received in the flow path 18, it changes the pH value of the detection surface 15a of the pH sensor 15 disposed in the flow path 18. This makes it possible to detect the attachment of foreign matter to the cover 12 based on the method described above with reference to FIG. 3. The detection surface 15a of the pH sensor 15 may be disposed anywhere along the path of movement of the liquid due to gravity. This allows for greater freedom in the placement of the pH sensor 15.

In this case, a pH sensor 15 that utilizes the glass electrode method, which is widely used as a so-called wet type, can be used. Figure 4A illustrates an example of the appearance of the flow path 18 in which the pH sensor 15 of this example is disposed, as viewed from above. Figure 4B illustrates a cross section of the flow path 18 as viewed from the direction of the arrow along line IVB-IVB in Figure 4A.

A recess 18d is formed in the bottom 18c of the flow path 18. The pH sensor 15 is disposed in the recess 18d. The recess 18d is filled with liquid LQ whose pH value is controlled. The controlled pH value is, for example, 7. The liquid LQ is, for example, pure water. The liquid LQ is supplied from a liquid supply source (not shown). As a result, the detection surface 15a of the pH sensor 15 is immersed in the liquid LQ.

When the liquid flowing down the surface of the cover 12 with foreign matter adhering thereto is received by the flow path 18 configured in this manner, an electromotive force corresponding to the difference between the pH value of the liquid LQ filling the recess 18d and the pH value of the liquid flowing through the flow path 18 is generated on the detection surface 15a. The pH sensor 15 outputs a pH signal S11 corresponding to this electromotive force.

When the presence of foreign matter is detected and a detection signal S12 is output (STEP 14 in FIG. 3), liquid LQ is resupplied from the liquid supply source described above, and the recess 18d is filled with new liquid LQ. The process returns to STEP 11, and in this state the pH value of the detection surface 15a is measured. The measured pH value is used as the new reference value for subsequent processes.

The drainage structure of the flow path 18 that utilizes gravity is not limited to the examples shown in Fig. 1, Fig. 4(A), and Fig. 4(B). For example, as shown in Fig. 4(C), liquid may be drained through a slope 18e and a through hole 18f provided on the bottom 18c. In this case, the second end 18b does not have to be open. The configuration shown in Fig. 4(C) can also be applied when a dry pH sensor 15 is used.

As shown in FIG. 1, the sensor system 1 may include a lamp unit 19. The lamp unit 19 is a device that emits illumination light to the outside of the vehicle 100. Examples of the lamp unit 19 include a headlamp unit, a width light unit, a turn signal unit, a fog light unit, and a rear combination lamp unit.

The lamp unit 19 is disposed within the accommodation chamber 13. Therefore, the lamp unit 19 is covered by the cover 12. The cover 12 also allows the passage of the illumination light emitted from the lamp unit 19. In this case, the cover 12 is formed from a material that is also transparent to visible light.

Because the lamp unit 19 has the function of supplying illumination light to the outside of the vehicle 100, it is generally placed in a location on the vehicle 100 where there are few obstructions. By also placing the LiDAR sensor unit 14 in such a location, information on the outside of the vehicle 100 can be obtained efficiently.

The processor 162 capable of executing the above processes may be provided as a general-purpose microprocessor that operates in cooperation with a general-purpose memory, or may be provided as part of a dedicated integrated circuit element. Examples of the general-purpose microprocessor include a CPU, an MPU, and a GPU. Examples of the general-purpose memory include a RAM and a ROM. A rewritable general-purpose memory may perform the function of the storage 163. Examples of the dedicated integrated circuit element include a microcontroller, an ASIC, and an FPGA. The processor 162 and the storage 163 may be provided as independent elements, or may be packaged in a single element.

Figure 5 illustrates an example of the configuration of a sensor system 2 according to the second embodiment. Components that are substantially the same as those in the sensor system 1 according to the first embodiment are given the same reference numerals, and repeated explanations will be omitted. The sensor system 2 is mounted on the vehicle 100 shown in Figure 2.

The sensor system 2 includes a strain gauge 25. The strain gauge 25 is disposed on the cover 12. More specifically, the strain gauge 25 is disposed at a position that avoids the light passing area 12a of the cover 12. Being disposed on the cover 12 is an example of being disposed adjacent to the cover.

The strain gauge 25 has a detection surface 25a. The strain gauge 25 is a device that measures the load applied to the detection surface 25a by detecting the strain of the detection surface 25a. The strain gauge 25 is configured to output a load signal S21 that corresponds to the measured load.

The sensor system 2 includes a control device 26. The control device 26 includes an input interface 261 and a processor 262. The control device 26 may be disposed within the accommodation compartment 13, or may be supported on the housing 11 outside the accommodation compartment 13. Alternatively, the control device 26 may be disposed at an appropriate position in the vehicle 100 separate from the housing 11.

The input interface 261 receives the load signal S21 output from the strain gauge 25. The processor 262 is configured to detect foreign matter adhering to the cover 12 based on the load signal S21. Examples of foreign matter include raindrops, snowflakes, sludge, and dead insects. The input interface 261 may include a signal processing circuit that converts the load signal S21 into a form suitable for processing by the processor 262 as necessary.

Figure 6 shows an example of the flow of processing performed by the processor 262. The processor 262 first acquires a load reference value (STEP 21). Specifically, the processor 262 causes the input interface 261 to accept a load signal S21 from the strain gauge 25 at a predetermined timing, thereby acquiring the load applied to the detection surface 25a at the predetermined timing as a reference value. An example of the predetermined timing is when the sensor system 1 is started up.

As shown in FIG. 5, the control device 26 includes a storage 263. The storage 263 can be realized by an appropriate rewritable semiconductor memory. The processor 262 stores data corresponding to the load as the reference value obtained as described above in the storage 263.

Then, the processor 262 causes the input interface 261 to receive the load signal S21 from the strain gauge 25 at a predetermined time interval. That is, the processor 262 acquires the measurement value of the strain gauge 25 at a predetermined time interval (STEP 22). The predetermined time interval is, for example, 100 milliseconds.

Then, the processor 262 compares the load measurement value of the detection surface 25a of the strain gauge 25 obtained in STEP 22 with the load reference value stored in the storage 263 in STEP 21. The processor 262 determines whether the difference between the measurement value and the reference value is equal to or greater than a predetermined value (STEP 23).

The change in the load value on the detection surface 25a of the strain gauge 25 that occurs after the reference value is obtained is most likely caused by a foreign object adhering to the detection surface 25a. In this case, there is a high possibility that a foreign object is also adhering to the cover 12. Therefore, if the difference between the measured value and the reference value related to the load on the detection surface 25a is equal to or greater than a predetermined value (YES in STEP 23), the processor 262 determines that a foreign object is adhering to the cover 12 and generates a detection signal S22 (STEP 24).

If the difference between the measured value and the reference value relating to the load on the detection surface 25a is less than the predetermined value (NO in STEP 23), the processor 262 determines that no foreign matter is attached to the cover 12, and the process returns to STEP 22.

As shown in FIG. 5, the control device 26 includes an output interface 264. The processor 262 causes the output interface 264 to output a detection signal S22. The detection signal S22 can be transmitted to another control device in the vehicle 100. For example, the other control device can notify an occupant of the vehicle 100 that a foreign object is attached to the cover 12 based on the detection signal S22. The notification can be made through at least one of a visual notification, an auditory notification, and a tactile notification.

Occupants who receive the notification can take appropriate action. For example, the sensor system 2 can be equipped with a nozzle 27 that sprays liquid toward the cover 12. Examples of liquid include water, hot water, and cleaning liquid. The occupant can operate the nozzle 27 to spray liquid. This can remove foreign matter adhering to the cover 12.

If a foreign object adheres to the light passage area 12a located on the path of the detection light and return light of the LiDAR sensor unit 14, it may hinder the LiDAR sensor unit 14 from detecting information outside the vehicle 100. However, the attachment of such a foreign object can be detected by the strain gauge 25 configured as described above, and appropriate processing can be taken according to the detection results. Therefore, it is possible to suppress a decrease in the information detection ability of the LiDAR sensor unit 14 covered by the cover 12 that forms part of the exterior surface of the vehicle 100.

Once the foreign matter removal process has been performed, the process returns to STEP 21. That is, the value of the load applied to the detection surface 25a of the strain gauge 25 at this point is acquired and used as a new reference value for the subsequent process. In other words, after the operation of the nozzle 27 can be an example of a predetermined timing for acquiring the load reference value.

As shown in FIG. 5, the detection signal S22 generated by the processor 262 can be used to operate the nozzle 27 described above. That is, when a foreign object adhering to the cover 12 is detected, the processor 262 can cause the nozzle 27 to spray liquid toward the cover 12.

This configuration allows the process of removing foreign matter adhering to the cover 12 to be automated. This enhances the effect of suppressing the deterioration of the information detection capability of the LiDAR sensor unit 14 covered by the cover 12 that forms part of the exterior surface of the vehicle 100.

As shown in FIG. 5, the nozzle 27 may include an ultrasonic actuator 271. The ultrasonic actuator 271 is a device that vibrates at a frequency in the ultrasonic band and excites a natural vibration in the liquid that is sprayed from the nozzle 27 toward the cover 12. In this case, the processor 262 outputs a control signal S23 to the output interface 264, which operates the ultrasonic actuator 271 when the nozzle 27 sprays the liquid.

With this configuration, the liquid sprayed from the nozzle 27 produces a so-called ultrasonic cleaning effect, further facilitating the removal of foreign matter adhering to the cover 12.

The position where the strain gauge 25 is placed is not limited to on the cover 12. If it is possible to detect foreign objects attached to the cover 12, it may be placed in a position adjacent to the cover 12 on the housing 11 or the body of the vehicle 100.

As shown in FIG. 5, the sensor system 1 may include a flow path 28. The flow path 28 is disposed below the light passing area 12a of the cover 12 and adjacent to the cover 12 to receive liquid that passes through at least the light passing area 12a and flows down onto the cover 12. Examples of such liquid include raindrops, melted snowflakes, dirty water splashed up from the road surface by the vehicle or another vehicle, and liquid sprayed from the nozzle 27 onto the cover 12. The flow path 28 may be formed as part of the housing 11 or the cover 12.

The flow path 28 has a drainage structure that utilizes gravity. In the example shown in FIG. 5, the second end 28b of the flow path 28 is located lower than the first end 28a. The second end 28b is open to the outside. Therefore, the liquid received by the flow path 28 flows through the flow path 28 toward the second end 28b and is discharged from the second end 28b.

In this case, the detection surface 25a of the strain gauge 25 can be disposed within the flow path 28. Therefore, the strain gauge 25 is disposed adjacent to the cover 12. FIG. 7A illustrates an example of the appearance of the flow path 28 in which the strain gauge 25 according to this example is disposed, as viewed from above. FIG. 7B illustrates a cross section of the flow path 28 as viewed from the direction of the arrow along the line VIIB-VIIB in FIG. 7A.

The liquid flowing down the surface of the cover 12 to which foreign matter is attached is likely to contain at least a portion of the foreign matter. Therefore, when the liquid is received in the flow path 28, it causes a greater change in the load applied to the detection surface 25a of the strain gauge 25 than when a liquid not containing the foreign matter is received. This makes it possible to detect the attachment of foreign matter to the cover 12 based on the method described above with reference to FIG. 6. The detection surface 25a of the strain gauge 25 may be placed anywhere on the path of movement of the liquid due to gravity. This allows for greater freedom in placement of the strain gauge 25.

The drainage structure of the flow path 28 that utilizes gravity is not limited to the examples shown in Fig. 5, Fig. 7(A), and Fig. 7(B). For example, as shown in Fig. 7(C), liquid may be drained through a slope 28e and a through hole 28f provided on the bottom 28c. In this case, the second end 28b does not need to be open.

As shown in FIG. 5, the sensor system 2 may include a lamp unit 29. The lamp unit 29 is a device that emits illumination light to the outside of the vehicle 100. Examples of the lamp unit 29 include a headlamp unit, a width light unit, a turn signal unit, a fog light unit, and a rear combination lamp unit.

The lamp unit 29 is disposed within the accommodation chamber 13. Therefore, the lamp unit 29 is covered by the cover 12. The cover 12 also allows the passage of the illumination light emitted from the lamp unit 29. In this case, the cover 12 is formed from a material that is also transparent to visible light.

Because the lamp unit 29 has the function of supplying illumination light to the outside of the vehicle 100, it is generally placed in a location on the vehicle 100 where there are few obstructions. By placing the LiDAR sensor unit 14 in such a location, information on the outside of the vehicle 100 can be obtained efficiently.

The processor 262 capable of executing the above processes may be provided as a general-purpose microprocessor that operates in cooperation with a general-purpose memory, or may be provided as part of a dedicated integrated circuit element. Examples of the general-purpose microprocessor include a CPU, an MPU, and a GPU. Examples of the general-purpose memory include a RAM and a ROM. A rewritable general-purpose memory may perform the function of the storage 263. Examples of the dedicated integrated circuit element include a microcontroller, an ASIC, and an FPGA. The processor 262 and the storage 263 may be provided as independent elements, or may be packaged in a single element.

The above-described embodiments are merely examples to facilitate understanding of the present invention. The configurations according to the above-described embodiments may be modified, improved, or combined as appropriate without departing from the spirit and scope of the present invention.

In addition to or instead of the LiDAR sensor unit 14 according to each of the above embodiments, an appropriate sensor unit that uses light to detect information outside the vehicle 100 may be placed in the accommodation chamber 13. Examples of such a sensor unit include a camera unit that uses visible light, a TOF (Time of Flight) camera unit that uses infrared light, and a radar unit that uses millimeter waves.

1, 2: Sensor system, 12: Cover, 14: LiDAR sensor unit, 15: pH sensor, 15a: Detection surface, 25: Strain gauge, 25a: Detection surface, 162, 262: Processor, 17, 27: Nozzle, 171, 271: Ultrasonic actuator, 18, 28: Flow path, 19, 29: Lamp unit, 100: Vehicle, S11: pH signal, S21: Load signal, LQ: Liquid with pH control

Claims (4)

A sensor system mounted on a vehicle,
A sensor unit that detects information outside the vehicle using light;
a cover forming a part of an exterior surface of the vehicle so as to cover the sensor unit and allowing the light to pass through;
a strain gauge having a detection surface disposed adjacent to the cover;
A flow path having a drainage structure utilizing gravity;
Equipped with
The detection surface is disposed within the flow path.
Sensor system. A nozzle capable of ejecting liquid;
a processor that causes the nozzle to eject the liquid toward the cover based on a signal output from the strain gauge;
Equipped with
The sensor system of claim 1 . An ultrasonic actuator is provided to apply ultrasonic waves to the liquid.
The sensor system of claim 2 . A lamp unit is provided for emitting illumination light to the outside of the vehicle,
The cover allows the illumination light to pass through.
A sensor system according to any one of claims 1 to 3 .

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