JP2014024427A - Exhaust gas detection device and exhaust gas detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust gas detection device capable of responsive detection of gas emission from a leading vehicle.SOLUTION: A radio wave receiving section 1 generates a radio wave image of a front side of an own vehicle as an objective on the basis of intensity of a radio wave emitted from the objective. A vehicle detecting section 3 detects an inter-vehicle distance between the own vehicle and a vehicle traveling ahead thereof. A high temperature detecting section 2 detects a high temperature region in the radio wave image having temperature, calculated on the basis of the intensity of the radio wave, not less than a threshold value. An exhaust port region deciding section 4 decides an exhaust port region corresponding to an exhaust port of the leading vehicle in the high temperature region detected by the high temperature detecting section. An odor estimating section 7 estimates an odor level of gas emission from the leading vehicle using the inter-vehicle distance detected by the vehicle detecting section on the basis of change in the intensity of the radio wave received by the radio wave receiving section 1 in the exhaust port region decided by the exhaust port region deciding section 4.

Description

  The present invention relates to an exhaust gas detection device and an exhaust gas detection method for detecting exhaust gas of a preceding vehicle.

  As a device for controlling the operation of a vehicle air conditioner, there has been proposed a control device that includes an odor sensor and controls to switch between an inside air circulation mode and an outside air introduction mode according to the outside air state detected by the odor sensor. (See Patent Document 1).

Japanese Utility Model Publication No. 5-41911

However, since the device described in Patent Document 1 is switched to the inside air circulation mode according to the outside air state detected by the odor sensor, there is a problem that it is necessary for the odor to once flow into the vehicle.
An object of the present invention is to provide an exhaust gas detection device and an exhaust gas detection method that can detect exhaust gas of a preceding vehicle with high response.

  The radio wave receiving unit generates a radio wave image based on the intensity of the radio wave radiated from the target with respect to the front of the host vehicle. The vehicle detection unit detects an inter-vehicle distance to a preceding vehicle that travels in front of the host vehicle. The high temperature detection unit detects a high temperature region in the radio wave image where the temperature calculated based on the radio wave intensity is equal to or higher than a threshold value. The exhaust port region determination unit determines an exhaust port region corresponding to the exhaust port of the preceding vehicle from the high temperature region detected by the high temperature detection unit. The odor estimation unit discharges the preceding vehicle based on the change in the strength of the radio wave received by the radio wave reception unit for the exhaust port region determined by the exhaust port region determination unit using the inter-vehicle distance detected by the vehicle detection unit. Estimate the exhaust gas odor level.

  ADVANTAGE OF THE INVENTION According to this invention, the exhaust-gas detection apparatus and exhaust-gas detection method which can detect the exhaust gas of a preceding vehicle with sufficient response can be provided.

1 is a schematic block diagram illustrating a basic configuration of an exhaust gas detection device according to an embodiment of the present invention. It is an example which illustrated the radio wave picture generated in the exhaust gas detection device concerning an embodiment of the invention. It is a figure explaining the exhaust pipe with which a common vehicle is provided. It is a flowchart explaining the exhaust-gas detection method which concerns on embodiment of this invention.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the embodiment described below exemplifies an apparatus and a method for embodying the technical idea of the present invention, and the technical idea of the present invention is an apparatus exemplified in the following embodiment. It is not specific to the method. The technical idea of the present invention can be variously modified within the technical scope described in the claims.

(Exhaust gas detector)
As shown in FIG. 1, the exhaust gas detection apparatus according to the embodiment of the present invention includes a radio wave reception unit 1, a high temperature detection unit 2, a vehicle detection unit 3, an exhaust port region determination unit 4, and intensity increase / decrease monitoring. Unit 5, rotational speed change estimation unit 6, odor estimation unit 7, catalyst temperature estimation unit 8, and inside air circulation control unit 9. An exhaust gas detection device according to an embodiment of the present invention is mounted on a vehicle (own vehicle) and controls an air conditioner according to the exhaust gas of a vehicle (preceding vehicle) traveling in front of the vehicle.

  The radio wave receiving unit 1 receives a radio wave radiated from a target in front of the host vehicle. The radio wave receiver 1 includes, for example, an array antenna in which a plurality of antennas are arranged in an array, and detects radio waves. The radio wave receiving unit 1 generates a two-dimensional radio wave image based on the received radio wave intensity (reception power). In the present invention, the “radio wave” refers to an electromagnetic wave having a frequency of about 30 to 10 THz.

  The high temperature detection unit 2 detects a high temperature region where the temperature calculated based on the intensity of the radio wave is equal to or higher than a threshold in the radio wave image based on the radio wave received by the radio wave reception unit 1. The high temperature detection unit 2 detects, for example, a region that emits radio waves equivalent to 200 ° C. or more as black body radiation as a high temperature region. The high temperature detection unit 2 may include a temperature detection unit that detects the ambient temperature, and may change the threshold according to the ambient temperature detected by the temperature detection unit. For example, the threshold value can be a value obtained by subtracting the environmental temperature from 200 ° C.

  The vehicle detection unit 3 detects a preceding vehicle traveling in front of the host vehicle and an inter-vehicle distance to the preceding vehicle. For example, the vehicle detection unit 3 detects a road surface area corresponding to the road surface on which the vehicle travels in the radio wave image generated by the radio wave reception unit 1, and calculates the length of a horizontal predetermined range among the boundaries of the detected road surface area. Set the boundary to have as the axis of symmetry. Next, the vehicle detection unit 3 sets a road surface reflection region between the set symmetry axis and the center line along the horizontal direction of the radio wave image, and compares the road surface reflection region and the road surface region with the output waveform of the pixel. When the waveform features are approximate, the road surface reflection area is detected as a preceding vehicle. The vehicle detection unit 3 can detect the preceding vehicle and the inter-vehicle distance to the preceding vehicle by various other methods.

  Further, the vehicle detection unit 3 calculates the vehicle width of the preceding vehicle from the detected preceding vehicle and the inter-vehicle distance to the preceding vehicle, and estimates the weight of the preceding vehicle based on the calculated vehicle width. The vehicle detection unit 3 may store a plurality of vehicle types and the weight of each vehicle type in advance, and estimate the weight of the preceding vehicle from the vehicle width and the exhaust port area of the preceding vehicle based on the stored information.

  The exhaust port region determination unit 4 determines the exhaust port region for the high temperature region detected by the high temperature detection unit 2 using the preceding vehicle and the inter-vehicle distance detected by the vehicle detection unit 3. For example, the exhaust port region determination unit 4 has a high temperature region detected by the high temperature detection unit 2 that is close to or at least partially included in the region of the preceding vehicle detected by the vehicle detection unit 3 and has a size within a predetermined range. The area is determined as the exhaust area.

  For example, as shown in FIG. 2, when the high temperature detection unit 2 detects the high temperature region 32 and the vehicle detection unit 3 detects the preceding vehicle 31 in the radio wave image, the exhaust port region determination unit 4 displays the high temperature region 32. Is determined as the exhaust port area of the preceding vehicle 31. Further, the exhaust port area determination unit 4 is considered to be unlikely to be an exhaust port, for example, in a high temperature region having a diameter exceeding 200 mm, and therefore, the high temperature region having a width calculated from the inter-vehicle distance of 200 mm or less is used. May be determined as the exhaust region.

  The processing in the radio wave reception unit 1, the high temperature detection unit 2, the vehicle detection unit 3, and the exhaust port region determination unit 4 is performed for each frame of a radio wave image, for example.

  The intensity increase / decrease monitoring unit 5 monitors the increase / decrease of the intensity of the radio wave received by the radio wave receiving unit 1 for the exhaust port region determined by the exhaust port region determining unit 4 using the inter-vehicle distance detected by the vehicle detection unit 3. When the exhaust area determination unit 4 determines a plurality of exhaust areas in the radio wave image, the intensity increase / decrease monitoring unit 5 integrates the intensity of the radio waves in the plurality of exhaust areas, and monitors the increase / decrease in intensity for the integrated value. You may do it.

  The rotational speed change estimation unit 6 estimates a change in the rotational speed of the engine of the preceding vehicle from the increase / decrease in intensity monitored by the intensity increase / decrease monitoring unit 5. For example, the rotation speed change estimation unit 6 calculates the time average of the intensity of the radio wave for each unit time for the exhaust region determined by the exhaust region determination unit 4. The engine speed change estimation unit 6 increases the engine speed when the intensity increases continuously by 10% or more for a predetermined time (for example, 1 second), and decreases when the engine speed decreases by 10% or more. The decrease may be estimated as a change in the rotational speed. Further, the rotational speed change estimation unit 6 may adjust the rotational speed change according to the ambient temperature.

  The odor estimation unit 7 estimates the odor level of the exhaust gas discharged by the preceding vehicle from the increase / decrease in intensity monitored by the intensity increase / decrease monitoring unit 5. For example, the odor estimation unit 7 estimates the odor level based on the change in the rotational speed estimated by the rotational speed change estimation unit 6. The odor estimation unit 7 can adjust the estimated odor level according to the weight of the preceding vehicle estimated by the vehicle detection unit 3.

  Further, the odor estimation unit 7 may detect the state of the road surface on which the preceding vehicle travels, and adjust the estimated odor level according to the detected road surface state. For example, the odor estimation unit 7 can detect the inclination of the road surface as the road surface state and adjust the estimated odor level according to the inclination of the road surface. The state of the road surface on which the preceding vehicle travels may be acquired from, for example, a GPS receiver and map data.

  The inside air circulation control unit 9 controls the air conditioner of the vehicle according to the inter-vehicle distance to the preceding vehicle detected by the vehicle detection unit 3 and the odor level estimated by the odor estimation unit 7. For example, the inside air circulation control unit 9 switches to the inside air circulation mode when the odor level estimated by the odor estimating unit 7 becomes a predetermined value or more.

  In addition to the estimated odor level and the inter-vehicle distance to the preceding vehicle, the inside air circulation control unit 9 determines, for example, the number and size of the exhaust regions when the exhaust region determination unit 4 determines a plurality of exhaust regions. The predetermined value of the odor level may be adjusted accordingly.

  When the intensity monitored by the intensity increase / decrease monitoring unit 5 is, for example, a monotonic increase of about 100 ° C. or more in terms of black body radiation temperature, or about 100 to 200 ° C., immediately after the engine of the preceding vehicle starts. If there is, switch to the inside air circulation mode. As a result, the exhaust port exhausts exhaust gas containing a large amount of nitrogen oxides immediately after the engine is started, so that the exhaust gas can be prevented from flowing into the vehicle.

  When the preceding vehicle detected by the vehicle detection unit 3 is moving and the temperature calculated from the intensity monitored by the intensity increase / decrease monitoring unit 5 is about 100 ° C., the inside air circulation control unit 9 determines whether the preceding vehicle is an electric vehicle or It may be determined that the vehicle is a fuel cell vehicle, and the air conditioning may be switched to the outside air introduction mode.

  For example, as shown in FIG. 3, an exhaust port of a vehicle including an engine is connected to an exhaust pipe 34 that exhausts exhaust gas of the engine through a catalyst 33. In general, the exhaust pipe 34 and the catalyst 33 contain a ceramic material having a large dielectric loss with respect to radio waves. For this reason, the catalyst 33 and the exhaust pipe 34 that become high in temperature have a large amount of radio wave radiation inside. The exhaust pipe 34 is generally made of a metal such as iron and has a feature that radio waves radiated from the internal catalyst 33 are easily radiated from the exhaust port without being diffused from the middle of the pipe to the outside.

  The exhaust gas detection device according to the embodiment of the present invention uses radio waves to determine a high temperature portion existing in the angle of view as an exhaust port of a vehicle when a predetermined condition is satisfied. Therefore, the exhaust gas detection device according to the embodiment of the present invention detects a target (exhaust port) with high accuracy by detecting heat using radio waves compared to infrared rays that diffuse from the high temperature part to the surroundings. The air conditioner can be controlled with good response.

  The catalyst temperature estimation unit 8 estimates the temperature of the catalyst from the temperature calculated based on the radio wave of the exhaust port region determined by the exhaust port region determination unit 4. If the estimated catalyst temperature continues to increase, the odor estimating unit 7 may determine that the preceding vehicle is in a state within a predetermined time after starting the engine and change the estimated odor level. .

(Exhaust gas detection method)
An example of the exhaust gas detection method in the exhaust gas detection apparatus according to the embodiment of the present invention will be described using the flowchart of FIG. In the following description, an exhaust gas detection device according to an embodiment of the present invention will be described as an exhaust gas detection device that is mounted on a host vehicle and controls air conditioning of the host vehicle.

  First, in step S1, the radio wave receiving unit 1 receives radio waves radiated from a target in front of the host vehicle. Next, the radio wave receiving unit 1 generates a radio wave image based on the intensity (reception power) of the received radio wave.

  In step S2, the high temperature detection unit 2 detects a high temperature region corresponding to a location where the temperature calculated based on the intensity of the radio wave is equal to or higher than the threshold in the radio wave image generated in step S1.

  In step S3, the vehicle detection unit 3 detects the preceding vehicle traveling in front of the host vehicle and the inter-vehicle distance to the preceding vehicle in the radio wave image generated in step S1.

  In step S4, the exhaust port region determination unit 4 determines a high temperature region that satisfies a predetermined condition as the exhaust port region for the high temperature region detected in step S2. The intensity increase / decrease monitoring unit 5 detects the intensity of the radio wave and the increase / decrease in the intensity of the exhaust port region determined by the exhaust port region determining unit 4.

  In step S5, the rotational speed change estimation unit 6 estimates a change in the rotational speed of the engine of the preceding vehicle from the increase or decrease in strength detected by the strength increase / decrease monitoring unit 5, and the odor estimation unit 7 Is used to estimate the odor level of the exhaust gas of the preceding vehicle.

  In step S6, the inside air circulation control unit 9 determines the air conditioner of the own vehicle based on the odor level of the exhaust gas of the preceding vehicle estimated by the odor estimation unit 7 and the inter-vehicle distance to the preceding vehicle detected by the vehicle detection unit 3. To control. The inside air circulation control unit 9 switches the air conditioner to the inside air circulation mode when the odor level estimated by the odor estimation unit 7 is a predetermined value or more.

  According to the exhaust gas detection device according to the embodiment of the present invention, the odor level of the exhaust gas is estimated based on the intensity of the radio wave radiated from the exhaust port of the preceding vehicle. Car exhaust gas can be detected.

  Further, according to the exhaust gas detection device according to the embodiment of the present invention, the high temperature detection unit changes the threshold value to be a high temperature region according to the ambient temperature, so even in a cold district or the like where the temperature of the catalyst changes. Exhaust gas can be detected with high accuracy and good response.

  Further, according to the exhaust gas detection device according to the embodiment of the present invention, the estimated odor level is adjusted according to the slope of the road surface, so even in the slope where the rate of acceleration and deceleration changes, with high accuracy, Exhaust gas can be detected with good response.

  Further, according to the exhaust gas detection device according to the embodiment of the present invention, the exhaust port region is determined according to the size of the high temperature region, so that erroneous detection of the exhaust port can be reduced.

  Further, according to the exhaust gas detection device according to the embodiment of the present invention, the exhaust gas of the preceding vehicle can be detected with good response, so that the air conditioner of the own vehicle can be controlled appropriately.

  Further, according to the exhaust gas detection device according to the embodiment of the present invention, the air conditioner of the own vehicle can be appropriately controlled with good response by detecting the preceding vehicle having the exhaust port on the side.

(Other embodiments)
As mentioned above, although this invention was described by embodiment, it should not be understood that the description and drawing which form a part of this indication limit this invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the above-described embodiment, the exhaust port region determination unit 4 includes the vehicle detection unit 3 when the preceding vehicle having the exhaust port on the side travels around the own vehicle within the angle of view of the radio wave reception unit 1. Based on this detection result, the side exhaust port may be determined as the exhaust port region. For example, the inside air circulation control unit 9 may switch the air conditioner to the inside air circulation mode on the assumption that there is a preceding vehicle having an exhaust port on the side, such as a truck on the side in the traveling direction of the host vehicle. . Thereby, when a truck with a large exhaust gas emission is detected as a preceding vehicle, the air conditioning can be controlled appropriately.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 Radio wave receiving part 2 High temperature detection part 3 Vehicle detection part 4 Exhaust port area | region determination part 5 Strength increase / decrease monitoring part 6 Rotational speed change estimation part 7 Odor estimation part 8 Catalyst temperature estimation part 9 Inside air circulation control part

Claims (8)

A radio wave receiving unit that generates a radio wave image based on the intensity of radio waves radiated from the subject in front of the host vehicle,
A vehicle detection unit that detects the inter-vehicle distance to a preceding vehicle traveling in front of the vehicle;
In the radio wave image, a high temperature detection unit that detects a high temperature region in which the temperature calculated based on the intensity of the radio wave is equal to or higher than a threshold value;
An exhaust region determining unit that determines an exhaust region corresponding to the exhaust port of the preceding vehicle from a high temperature region detected by the high temperature detector;
Exhaust gas exhausted by the preceding vehicle based on a change in intensity of radio waves received by the radio wave receiving unit for an exhaust port area determined by the exhaust port area determining unit using an inter-vehicle distance detected by the vehicle detection unit An exhaust gas detection device comprising: an odor estimation unit that estimates an odor level of gas.   The exhaust gas detection device according to claim 1, wherein the high temperature detection unit changes the threshold value according to an ambient temperature.   The exhaust gas detection device according to claim 1 or 2, wherein the odor estimation unit adjusts an estimated odor level according to a slope of a road surface.   The exhaust gas detection device according to any one of claims 1 to 3, wherein the exhaust port region determination unit determines a high temperature region having a predetermined size or less as an exhaust port region.   5. The inside air circulation control unit that switches the air conditioner of the vehicle to the internal circulation mode when the odor level estimated by the odor estimation unit is equal to or higher than a predetermined value. The exhaust gas detection device described in 1.   The internal air circulation control unit switches the air conditioner of the own vehicle to an internal circulation mode when a temperature calculated based on a radio wave intensity is within a predetermined range for the exhaust port region. The exhaust gas detection device according to any one of 1 to 5.   The inside air circulation control unit switches the air conditioner of the own vehicle to the internal circulation mode when the exhaust port region setting unit sets the exhaust port region to the side of the preceding vehicle detected by the vehicle detection unit. The exhaust gas detection device according to any one of claims 1 to 6, wherein A radio wave receiving step for generating a radio wave image based on the intensity of the radio wave radiated from the subject in front of the own vehicle;
A vehicle detection step for detecting an inter-vehicle distance to a preceding vehicle traveling in front of the host vehicle;
In the radio wave image, a high temperature detection step for detecting a high temperature region in which the temperature calculated based on the intensity of the radio wave is equal to or higher than a threshold value;
An exhaust region determination step for determining an exhaust region corresponding to the exhaust port of the preceding vehicle from the high temperature region detected in the high temperature detection step;
An odor that estimates an odor level of exhaust gas discharged from the preceding vehicle based on a change in radio wave intensity for the exhaust port area determined in the exhaust port area determination using the inter-vehicle distance detected by the vehicle detection unit. An exhaust gas detection method comprising: an estimation step.

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