阅读说明：本技术 传感器系统 (Sensor system ) 是由 井上宙 于 2020-03-09 设计创作，主要内容包括：传感器(2)检测车辆(100)的外部的信息。除雾装置(3)朝向传感器(2)的检测区域(A)的至少一部分供给水、化合物、暖风、带电微粒、超声波以及红外线的至少一个。(The sensor (2) detects information outside the vehicle (100). The defogging device (3) supplies at least one of water, chemical compounds, warm air, charged particles, ultrasonic waves, and infrared rays to at least a part of a detection region (A) of the sensor (2).)

1. A sensor system mounted on a vehicle, characterized by comprising:

a sensor that outputs a signal corresponding to information outside the vehicle; and

and a defogging device that supplies at least one of water, a chemical compound, warm air, charged particles, ultrasonic waves, and infrared rays toward at least a portion of a detection region of the sensor.

2. The sensor system of claim 1,

the compound comprises at least one of sodium chloride, calcium chloride, and silver iodide.

3. The sensor system according to claim 1 or 2,

a processor is provided for activating the defogging device based on the signal.

4. The sensor system according to any one of claims 1 to 3,

the defogging device is provided with a processor which enables the defogging device to be started in linkage with the lighting of the fog lamp.

5. The sensor system according to any one of claims 1 to 4,

the sensors include at least one of a LiDAR sensor, a camera, a millimeter wave radar, and an ultrasonic sensor.

Technical Field

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

Background

In order to assist driving of a vehicle, a sensor for detecting external information of the vehicle is mounted on a vehicle body. Patent document 1 discloses a radar as such a sensor.

The term "driving assistance" used in the present specification means a control process of performing at least one of a driving operation (steering wheel operation, acceleration, deceleration, and the like), monitoring of a running environment, and backup of the driving operation, at least in part. That is, it means that the vehicle includes a partial driving assistance from a collision damage reduction braking function, a lane keeping assistance function, or the like to a full automatic driving action.

Documents of the prior art

Patent document

Patent document 1: japanese patent application laid-open No. 2007-106199

Disclosure of Invention

Problems to be solved by the invention

It is required to suppress a decrease in information detection capability by a sensor mounted on a vehicle.

Means for solving the problems

One aspect of the present invention for responding to the above-described request is a sensor system mounted on a vehicle, including:

a sensor that outputs a signal corresponding to information outside the vehicle; and

and a defogging device that supplies at least one of water, a chemical compound, warm air, charged particles, ultrasonic waves, and infrared rays toward at least a portion of a detection region of the sensor.

The sensor may include at least one of a lidar (light Detection and ranging) sensor, a camera, a millimeter wave radar, and an ultrasonic sensor.

Fog is a phenomenon in which fine water droplets float in the atmosphere. The sensor detects information by absorbing water molecules constituting water droplets with invisible light, millimeter waves, and ultrasonic waves. Therefore, when invisible light, millimeter waves, or ultrasonic waves are emitted into the atmosphere in which the fog is generated, there is a possibility that reflected light or reflected waves sufficient for detecting information cannot be obtained. When the sensor is a camera, the field of view may become unclear due to fog, and desired image information may not be acquired.

With the above configuration, an environmental condition for thinning the mist can be formed in the space including the detection region of the sensor. Therefore, the decrease in the information detection capability of the sensor due to the fog can be suppressed.

For example, the supplied water is combined with fine water droplets floating on standby to form mist. With this combination, the size and weight increase, so that the water droplets can no longer float in the atmosphere, but fall to the ground. This can thin or eliminate the mist.

When at least one of a compound, charged fine particles, ultrasonic waves, and infrared rays is supplied, condensation of fine water droplets floating on standby to form mist is promoted. With condensation, the size and weight increase so that the water droplets can no longer float in the atmosphere, but fall to the ground. This can thin or eliminate the mist.

The compound may comprise at least one of sodium chloride, calcium chloride, and silver iodide.

The mist is formed of fine water droplets whose water vapor pressure reaches a saturated state. When the warm air is supplied, the temperature of the road surface or the space on which the warm air is blown rises, and the saturated vapor pressure also rises further. The fine water droplets cannot form mist because the water vapor pressure thereof does not reach a saturated state. This can thin or eliminate the mist.

The sensor system described above may be configured as follows.

A processor is provided for activating the defogging device based on the signal.

For example, if the processor determines that a significant deterioration in the quality of the signal (or corresponding information) output from the sensor is detected, the defogging device is activated. With this configuration, the defogging operation for suppressing the decrease in the information detection capability of the sensor can be automated.

The sensor system described above may be configured as follows.

The defogging device is provided with a processor which enables the defogging device to be started in linkage with the lighting of the fog lamp.

When the fog lamp is turned on, the fog is likely to be generated. Therefore, by configuring to activate the defogging device in conjunction with the turning on of the fog lamp, it is possible to automate a defogging operation for suppressing a decrease in the information detection capability of the sensor.

Drawings

Fig. 1 illustrates a configuration of a sensor system of an embodiment.

Fig. 2 shows another configuration example of the sensor system of fig. 1.

Detailed Description

Hereinafter, examples of the embodiments will be described in detail with reference to the attached drawings. In the drawings used in the following description, the scale is appropriately changed so that each member can be recognized.

In the attached drawings, an arrow F indicates a front direction of the illustrated configuration. Arrow B indicates the rearward direction of the illustrated construction. Arrow U indicates the upward direction of the illustrated construction. Arrow D indicates the downward direction of the illustrated configuration.

Fig. 1 illustrates a configuration of a sensor system 1 according to an embodiment. Sensor system 1 is mounted on vehicle 100. The shape of the body of the vehicle 100 is merely an example.

The sensor system 1 includes a sensor 2. Sensor 2 is mounted at an appropriate position in vehicle 100, and detects external information of vehicle 100.

The sensor 2 is for example a LiDAR sensor. The LiDAR sensor includes a configuration that emits invisible light to the outside of the vehicle 100, and a configuration that detects return light as a result of reflection of the invisible light by an object present outside the vehicle 100. The LiDAR sensor may be provided with a scanning mechanism that changes the emission direction (i.e., the detection direction) and scans the invisible light, if necessary. The wavelength of the non-visible light is, for example, 905 nm.

The LiDAR sensor can detect a distance to the object associated with the return light based on, for example, a time from a timing when the invisible light is emitted in a certain direction to a time when the return light is detected. Further, by associating and accumulating such distance data with the detection position, information on the shape of the object associated with the return light can be detected. In addition to or instead of this, it is possible to detect information on properties such as the material of the object associated with the return light based on the difference in the waveforms of the outgoing light and the return light. The LiDAR sensor is configured to output a signal corresponding to the detected information.

The sensor 2 is for example a camera. The camera is a device for acquiring image information outside the vehicle 100. The image may include at least one of a still image and a moving image. The camera is configured to output a signal corresponding to the acquired image information.

The sensor 2 is, for example, a millimeter wave radar. The millimeter wave radar has a configuration for transmitting millimeter waves and a configuration for receiving reflected waves resulting from reflection of the millimeter waves by an object located outside the vehicle 100. The frequency of the millimeter wave is, for example, any one of 24GHz, 26GHz, 76GHz, and 79 GHz.

The millimeter wave radar can detect the distance to an object associated with a reflected wave based on the time from the timing of transmitting a millimeter wave in a certain direction to the reception of the reflected wave, for example. Further, by accumulating such distance data in association with the detected position, information on the movement of the object associated with the reflected wave can be acquired. The millimeter wave radar is configured to output a signal corresponding to the detected information.

The sensor 2 is, for example, an ultrasonic sensor. The ultrasonic sensor includes a structure for transmitting ultrasonic waves (several tens kHz to several GHz) and a structure for receiving reflected waves resulting from reflection of the ultrasonic waves by an object located outside the vehicle 100.

The ultrasonic sensor can detect the distance to an object associated with a reflected wave based on the time from the timing of transmitting the ultrasonic wave in a certain direction to the reception of the reflected wave, for example. Further, by accumulating such distance data in association with the detected position, information on the movement of the object associated with the reflected wave can be acquired. The ultrasonic sensor is configured to output a signal corresponding to the detected information.

Fog is a phenomenon in which fine water droplets float in the atmosphere. The invisible light, millimeter wave, and ultrasonic wave used for the sensor 2 are used for absorption of water molecules constituting the water droplets. Therefore, when invisible light, millimeter waves, or ultrasonic waves are emitted into the atmosphere in which the fog is generated, there is a possibility that reflected light or reflected waves sufficient for detecting information cannot be obtained. If the sensor 2 is a camera, the field of view may become unclear due to fog, and desired image information may not be acquired.

To cope with this problem, the sensor system 1 includes a defogging device 3. The defogging device 3 is a device that creates an environmental condition in which fog is reduced in a space S including a detection region a in which information can be detected by the sensor 2.

The defogging device 3 may be mounted at an appropriate position in the vehicle 100 in accordance with the position of the detection area a of the sensor 2. In the example shown in fig. 1, the defogging device 3 is disposed on the ceiling portion of the vehicle 100.

The defogging device 3 is, for example, a device that sprays water W toward at least a part of the detection area a of the sensor 2.

The sprayed water W is combined with fine water droplets floating on standby to form mist. With this combination, the size and weight increase, so that the water droplets can no longer float in the atmosphere, but fall to the ground. This can thin or eliminate the spray.

The defogging device 3 is, for example, a device that ejects the compound C toward at least a part of the detection area a of the sensor 2. Examples of the compound C include sodium chloride, calcium chloride, and silver iodide. Compound C may also be mixed with water W.

These sprayed compounds C promote the coagulation of fine water droplets floating to form mist during standby. With condensation, the size and weight increase so that the water droplets can no longer float in the atmosphere, but fall to the ground. This can thin or eliminate the mist.

In addition to or instead of the above-described compounds, at least one of charged fine particles, ultrasonic waves, and infrared rays may be supplied to at least a part of the detection region a of the sensor 2 in order to promote condensation of fine water droplets forming mist. However, in the case where the sensor 2 is an ultrasonic sensor, the defogging device 3 does not use ultrasonic waves in order to avoid interference. Similarly, in the case where the sensor 2 uses infrared rays for information detection, the defogging device 3 does not use infrared rays in order to avoid interference.

In addition to or instead of the above configuration, the defogging device 3 may include a device that supplies the warm air H toward at least a portion of the detection area a of the sensor 2. In the example shown in fig. 1, the device is disposed at the front end portion of the vehicle 100.

The mist is formed of fine water droplets whose water vapor pressure reaches a saturated state. The temperature of the road surface or the space on which the warm air H is blown rises, and the saturated vapor pressure also rises further. The fine water droplets cannot form mist because the water vapor pressure thereof does not reach a saturated state. This can thin or eliminate the mist.

By the above-described methods, an environmental condition for thinning the mist can be formed in the space S including the detection region a of the sensor 2. The two-dot chain line in fig. 1 indicates an interface between the space S in which the environmental conditions are controlled in this manner and the normal atmosphere. This can suppress a decrease in the information detection capability of the sensor 2 due to the fog.

The supply of at least one of the water W, the compound C, the warm air H, the charged particles, the ultrasonic waves, and the infrared rays by the defogging device 3 may be continuously performed or intermittently performed.

As illustrated in fig. 2, the sensor system 1 may have a control device 4. The control device 4 may have an input interface 41, a processor 42, and an output interface 43. The control device 4 can be mounted at an appropriate position in the vehicle 100.

As described above, the sensor 2 outputs the sensor signal S1 corresponding to the detected information. The input interface 41 receives a sensor signal S1 output from the sensor 2. The input interface 41 may contain signal processing circuitry as needed to convert the sensor signal S1 into a form suitable for processing by the processor 42.

The processor 42 is configured to control the operation of the defogging device 3 based on the sensor signal S1 received from the sensor 2. Specifically, the processor 42 determines whether a significant deterioration in the quality of the sensor signal S1 (or corresponding information) is identified. The term "significant deterioration" means a state in which a desired signal level or signal waveform cannot be obtained. If significant deterioration in the quality of the sensor signal S1 is detected, the processor 42 generates a control signal S2 for activating the defogging device 3.

The processor 42 outputs the control signal S2 from the output interface 43. Upon receiving the control signal S2, the defogging device 3 executes the above-described defogging operation. The output interface 43 may include a signal processing circuit that converts the control signal S2 into a form suitable for processing by the defogging device 3, as desired.

With this configuration, the defogging operation for suppressing the deterioration of the information detection capability of the sensor 2 can be automated.

The processor 42 continuously monitors the quality of the sensor signal S1 received by the input interface 41. When the quality of the sensor signal S1 is confirmed to be restored by the operation of the defogging device 3, the processor 42 generates a control signal S3 for stopping the operation of the defogging device 3 and outputs the control signal from the output interface 43. The output interface 43 may include a signal processing circuit that converts the control signal S3 into a form suitable for processing by the defogging device 3, as desired. Upon receiving the control signal S3, the defogging device 3 stops the defogging operation.

In addition to or instead of this, the input interface 41 may receive the lighting signal S4 indicating that the fog lamp 101 mounted on the vehicle 100 is turned on. In this case, the input interface 41 may include a signal processing circuit that converts the lighting signal S4 into a form suitable for processing by the processor 42 as necessary.

The processor 42 is configured to control the operation of the defogging device 3 in conjunction with turning off the fog lamp 101. Specifically, when the input interface 41 receives the lighting signal S4, the processor 42 generates a control signal S2 for activating the defogging device 3 and outputs the control signal from the output interface 43. Upon receiving the control signal S2, the defogging device 3 executes the defogging operation described above.

When the fog lamp 101 is turned on, the fog is likely to be generated. Therefore, by configuring to activate the defogging device 3 in conjunction with the turning on of the fog lamp 101, it is possible to automate a defogging operation for suppressing a decrease in the information detection capability of the sensor 2.

When the fog lamp 101 is turned off, the lighting signal S4 disappears. In this case, the processor 42 generates a control signal S3 for stopping the operation of the defogging device 3 and outputs the control signal from the output interface 43. Upon receiving the control signal S3, the defogging device 3 stops the defogging operation.

The processor 42 capable of executing the above-described processing may be provided as a general-purpose microprocessor operating in cooperation with a general-purpose memory, or may be provided as a part of an application-specific 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. Examples of the application specific integrated circuit element include a microcontroller, an ASIC, and an FPGA.

The above-described embodiments are merely examples for easy understanding of the present disclosure. The configuration of the above-described embodiment can be appropriately modified and improved without departing from the gist of the present disclosure.

Referring to fig. 1, a defogging operation for suppressing a decrease in the detection capability of the sensor 2 with respect to information on an area located at least in front of the vehicle 100 is described. As illustrated in this figure, the sensor 2 may be configured to detect information of an area located at least rearward of the vehicle 100. In this case, although not shown, the defogging device 3 is configured to supply at least one of water, chemical compounds, warm air, charged fine particles, ultrasonic waves, and infrared rays toward at least a portion of the detection region of the sensor 2 located at least rearward of the vehicle 100.

As contents constituting a part of the present disclosure, contents of japanese patent application No. 2019-052838, filed 3, 20, 2019, are cited.