阅读说明：本技术 车载显示系统 (Vehicle-mounted display system ) 是由 伊藤广矩 于 2021-05-18 设计创作，主要内容包括：提供能够使与其他车辆对应的其他车辆图标显示在适当位置的车载显示系统。车载显示系统具备：激光雷达,其测定自身车辆周围的第1其他车辆的位置；周边车辆位置测定装置,测定未通过激光雷达测定位置的、自身车辆周围的第2其他车辆的位置；显示装置,其显示与自身车辆周围的区划线对应的区划线图标和与自身车辆周围的其他车辆对应的其他车辆图标；和显示控制装置,其对显示装置中的区划线图标和其他车辆图标的显示进行控制。显示控制装置确定与通过周边车辆位置测定装置测定的第2其他车辆的前后方向上的位置对应的前后方向上的显示位置和与第2其他车辆的行驶车道内的左右方向上的位置对应的左右方向上的显示位置作为其他车辆图标的显示位置。(Provided is an in-vehicle display system capable of displaying other vehicle icons corresponding to other vehicles at appropriate positions. The vehicle-mounted display system is provided with: a laser radar that measures the position of the 1 st other vehicle around the own vehicle; a peripheral vehicle position measuring device that measures the position of the 2 nd other vehicle around the host vehicle whose position is not measured by the laser radar; a display device that displays a scribe line icon corresponding to a scribe line around the own vehicle and another vehicle icon corresponding to another vehicle around the own vehicle; and a display control device that controls display of the dash line icon and the other vehicle icons in the display device. The display control device specifies, as the display positions of the other-vehicle icons, the display position in the front-rear direction corresponding to the position in the front-rear direction of the 2 nd other vehicle measured by the nearby-vehicle position measuring device and the display position in the left-right direction corresponding to the position in the left-right direction within the traveling lane of the 2 nd other vehicle.)

1. An in-vehicle display system that displays a host vehicle and other vehicles around the host vehicle, the in-vehicle display system comprising:

a laser radar that measures the position of the 1 st other vehicle around the own vehicle;

a nearby vehicle position measurement device that measures a position of a 2 nd other vehicle around the host vehicle, the position of which has not been measured by the laser radar;

a display device that displays a scribe line icon corresponding to a scribe line around the own vehicle and another vehicle icon corresponding to another vehicle around the own vehicle; and

a display control device that controls display of the scribe line icon and the other vehicle icon in the display device,

the display control device includes a vehicle position specifying unit that specifies, as the display position of the another vehicle icon corresponding to the 2 nd another vehicle, a display position in a front-rear direction corresponding to the position in the front-rear direction of the 2 nd another vehicle measured by the nearby vehicle position measuring device and a display position in a left-right direction corresponding to the position in the left-right direction in the lane in which the 2 nd another vehicle is traveling.

2. The in-vehicle display system according to claim 1,

the vehicle position specifying unit specifies, as the display position of the another vehicle icon corresponding to the 1 st another vehicle, a display position in the front-rear direction and a display position in the left-right direction corresponding to a position in the front-rear direction and the left-right direction of the 1 st another vehicle whose position is measured by the laser radar.

3. The in-vehicle display system according to claim 1 or 2,

the vehicle position determination unit estimates a center position in the left-right direction of a lane on which the 2 nd other vehicle is traveling based on a position in the front-rear direction of the 2 nd other vehicle, and displays another vehicle icon corresponding to the 2 nd other vehicle at a display position in the front-rear direction and in the left-right direction corresponding to a position in the front-rear direction and in the left-right direction of the 2 nd other vehicle measured by the peripheral vehicle position measurement device when a distance between the estimated center position in the left-right direction of the lane and the center position in the left-right direction of the 2 nd other vehicle measured by the peripheral vehicle position measurement device is equal to or less than a predetermined distance.

4. The in-vehicle display system according to any one of claims 1 to 3,

the display control device further includes a scribe line position specifying unit that specifies a position of a scribe line of a road on which the host vehicle is traveling based on map information of the road on which the host vehicle is traveling, specifies the specified position of the scribe line as a display position of a scribe line icon corresponding to the scribe line,

the vehicle position determination unit estimates a position in the right-left direction in the lane closest to the position in the right-left direction of the 2 nd other vehicle, based on the determined position of the scribe line and the position in the front-rear direction of the 2 nd other vehicle.

5. The in-vehicle display system according to any one of claims 1 to 3,

further comprises an outside camera for photographing the road around the vehicle,

the display control device further includes a scribe line position specifying unit that specifies a position of a scribe line of a road on which the host vehicle is traveling based on an image captured by the vehicle exterior camera, specifies the specified position of the scribe line as a display position of a scribe line icon corresponding to the scribe line,

the vehicle position determination unit estimates a position in the right-left direction in the lane closest to the position in the right-left direction of the 2 nd other vehicle, based on the determined position of the scribe line and the position in the front-rear direction of the 2 nd other vehicle.

6. The in-vehicle display system according to claim 3,

further comprises an outside camera for photographing the road in front of the vehicle,

the vehicle position specifying unit calculates an angle of the 2 nd other vehicle with respect to a traveling direction of the host vehicle based on the image of the 2 nd other vehicle captured by the vehicle exterior camera, specifies a position in a left-right direction of the 2 nd other vehicle based on the calculated angle and a position in the front-rear direction of the 2 nd other vehicle measured by the peripheral vehicle position measuring device, and displays an other vehicle icon corresponding to the 2 nd other vehicle in the front-rear direction and the left-right direction corresponding to the position in the front-rear direction and the left-right direction of the 2 nd other vehicle measured by the peripheral vehicle position measuring device when a distance between the specified position in the left-right direction of the 2 nd other vehicle and the position in the left-right direction of the 2 nd other vehicle measured by the peripheral vehicle position measuring device is equal to or less than a predetermined distance Is displayed at the display position.

7. The in-vehicle display system according to claim 6,

the vehicle position specifying unit displays another vehicle icon corresponding to the 2 nd another vehicle at a display position in a front-rear direction and a display position in a left-right direction corresponding to a position in the front-rear direction and the left-right direction of the 2 nd another vehicle measured by the nearby vehicle position measuring device, when the host vehicle changes lanes.

8. An in-vehicle display system that displays a host vehicle and other vehicles around the host vehicle, the in-vehicle display system comprising:

a peripheral vehicle position measurement device that detects a position of another vehicle around the host vehicle;

a display device that displays a scribe line icon corresponding to a scribe line around the own vehicle and another vehicle icon corresponding to another vehicle around the own vehicle; and

a display control device that controls display of the scribe line icon and the other vehicle icon in the display device,

the display control device, when the position of a preceding vehicle that precedes the host vehicle and runs in the same lane and a preceding vehicle that precedes the preceding vehicle and runs in the same lane are determined by the surrounding vehicle position determination device, displays another vehicle icon corresponding to the preceding vehicle at a display position in the front-rear direction and in the left-right direction corresponding to the position in the front-rear direction and in the left-right direction of the preceding vehicle determined by the surrounding vehicle position determination device, and displays another vehicle icon corresponding to the preceding vehicle at a display position in the front-rear direction corresponding to the position in the front-rear direction of the preceding vehicle determined by the surrounding vehicle position determination device and a display position in the left-right direction corresponding to the position in the left-right direction within the lane in which the preceding vehicle runs.

Technical Field

The present disclosure relates to an in-vehicle display system.

Background

The following proposals have been made in the past: in order to detect the position of another vehicle around the host vehicle, a radar such as a millimeter wave radar is used (for example, patent documents 1 to 5). Further, there is proposed an in-vehicle display system (for example, patent document 1) for displaying a vehicle icon corresponding to the host vehicle and other vehicles around the host vehicle and a scribe line icon corresponding to a lane ahead of the host vehicle on a display in the vehicle based on the position of the other vehicle detected in this way.

Documents of the prior art

Patent document 1: japanese patent laid-open publication No. 2018-92291

Patent document 2: japanese patent laid-open No. 2000-131433

Patent document 3: japanese patent laid-open publication No. 2017-227506

Patent document 4: japanese laid-open patent publication No. 2009-90840

Patent document 5: japanese patent laid-open No. 2014-89691

Disclosure of Invention

Technical problem to be solved by the invention

However, when the position of another vehicle around the host vehicle is detected from a part of radars such as millimeter-wave radars or an image of an exterior camera that captures the front of the host vehicle, the position of the other vehicle may not necessarily be accurately detected. If the position of another vehicle cannot be accurately detected in this way, another vehicle icon indicating the other vehicle cannot be displayed at an appropriate position on the display in the vehicle.

In view of the above problems, an object of the present disclosure is to provide an in-vehicle display system capable of displaying other vehicle icons corresponding to other vehicles at appropriate positions.

Means for solving the problems

The gist of the present disclosure is as follows.

(1) An in-vehicle display system that displays a host vehicle and other vehicles around the host vehicle, the in-vehicle display system comprising: a laser radar that measures the position of the 1 st other vehicle around the own vehicle; a nearby vehicle position measurement device that measures a position of a 2 nd other vehicle around the host vehicle, the position of which has not been measured by the laser radar; a display device that displays a scribe line icon corresponding to a scribe line around the own vehicle and another vehicle icon corresponding to another vehicle around the own vehicle; and a display control device that controls display of the scribe line icon and the another vehicle icon on the display device, wherein the display control device includes a vehicle position specifying unit that specifies a display position in a front-rear direction corresponding to a position in a front-rear direction of the 2 nd another vehicle measured by the nearby vehicle position measuring device and a display position in a left-right direction corresponding to a position in a left-right direction in a lane in which the 2 nd another vehicle is traveling as display positions of the another vehicle icon corresponding to the 2 nd another vehicle.

(2) The in-vehicle display system according to the above (1), wherein the vehicle position specifying unit specifies a display position in a front-rear direction and a display position in a left-right direction corresponding to a position in the front-rear direction and the left-right direction of the 1 st another vehicle whose position is measured by the laser radar as the display position of the another vehicle icon corresponding to the 1 st another vehicle.

(3) The in-vehicle display system according to the above (1) or (2), wherein the vehicle position determination unit estimates a center position in the left-right direction of the lane on which the 2 nd another vehicle is traveling based on the position in the front-rear direction of the 2 nd another vehicle, and displays another vehicle icon corresponding to the 2 nd another vehicle at a display position in the front-rear direction and in the left-right direction corresponding to the position in the front-rear direction and in the left-right direction of the 2 nd another vehicle measured by the nearby vehicle position measurement device, when a distance between the estimated center position in the left-right direction of the lane and the center position in the left-right direction of the 2 nd another vehicle measured by the nearby vehicle position measurement device is equal to or less than a predetermined distance.

(4) The in-vehicle display system according to any one of the above (1) to (3), wherein the display control device further includes a scribe line position specifying unit that specifies a position of a scribe line of a road on which the host vehicle is traveling based on map information of the road on which the host vehicle is traveling, specifies the specified position of the scribe line as a display position of a scribe line icon corresponding to the scribe line, and the vehicle position specifying unit estimates a position in a left-right direction in a lane closest to a position in the left-right direction of the 2 nd other vehicle based on the specified position of the scribe line and a position in a front-rear direction of the 2 nd other vehicle.

(5) The in-vehicle display system according to any one of the above (1) to (3), further comprising an external camera that captures an image of a road around the host vehicle, wherein the display control device further comprises a scribe line position specifying unit that specifies a position of a scribe line of the road on which the host vehicle is traveling based on the image captured by the external camera, and specifies the specified position of the scribe line as a display position of a scribe line icon corresponding to the scribe line, and wherein the vehicle position specifying unit specifies a position in a left-right direction in the lane closest to the position in the left-right direction of the 2 nd other vehicle based on the specified position of the scribe line and the position in the front-rear direction of the 2 nd other vehicle.

(6) The in-vehicle display system according to the above (3), further comprising an outside-vehicle camera that captures an image of a road ahead of the host vehicle, wherein the vehicle position specifying unit calculates an angle of the travel direction of the 2 nd another vehicle with respect to the travel direction of the host vehicle based on the image of the 2 nd another vehicle captured by the outside-vehicle camera, specifies a position in the left-right direction of the 2 nd another vehicle based on the calculated angle and a position in the front-rear direction of the 2 nd another vehicle measured by the nearby-vehicle position measuring device, and when a distance between the specified position in the left-right direction of the 2 nd another vehicle and the position in the left-right direction of the 2 nd another vehicle measured by the nearby-vehicle position measuring device is equal to or less than a predetermined distance, and displaying another vehicle icon corresponding to the 2 nd another vehicle at a display position in the front-rear direction and in the left-right direction corresponding to the position in the front-rear direction and in the left-right direction of the 2 nd another vehicle measured by the nearby vehicle position measuring device.

(7) The in-vehicle display system according to the above (6), wherein the vehicle position specifying unit displays another vehicle icon corresponding to the 2 nd another vehicle at a display position in a front-rear direction and a display position in a left-right direction corresponding to a position in the front-rear direction and the left-right direction of the 2 nd another vehicle measured by the nearby vehicle position measuring device, when the host vehicle changes lanes.

(8) An in-vehicle display system that displays a host vehicle and other vehicles around the host vehicle, the in-vehicle display system comprising: a peripheral vehicle position measurement device that detects a position of another vehicle around the host vehicle; a display device that displays a scribe line icon corresponding to a scribe line around the own vehicle and another vehicle icon corresponding to another vehicle around the own vehicle; and a display control device that controls display of a dash-dot line icon and another vehicle icon in the display device, wherein when the position of a preceding vehicle that runs ahead of the host vehicle and on the same lane and a preceding vehicle that runs ahead of the preceding vehicle and on the same lane are determined by the peripheral vehicle position measurement device, the display control device causes the other vehicle icon corresponding to the preceding vehicle to be displayed at display positions in the front-rear direction and in the left-right direction that correspond to positions in the front-rear direction and in the left-right direction of the preceding vehicle determined by the peripheral vehicle position measurement device, and causes the other vehicle icon corresponding to the preceding vehicle to be displayed at display positions in the front-rear direction that correspond to the position in the front-rear direction of the preceding vehicle determined by the peripheral vehicle position measurement device and display positions in the left-right direction that correspond to the position in the left-right direction of the lane on which the preceding vehicle runs Showing the location.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, an in-vehicle display system capable of displaying other vehicle icons corresponding to other vehicles at appropriate positions is provided.

Drawings

Fig. 1 is a schematic diagram showing a configuration of an in-vehicle display system according to an embodiment.

Fig. 2 is a plan view of a vehicle mounted with an in-vehicle display system.

Fig. 3 (a) and (B) are diagrams showing a method of measuring a distance to an object by a laser radar.

Fig. 4 is a diagram showing an example of a part of a display screen of the display.

Fig. 5 is a hardware configuration diagram showing an ECU as an embodiment of the display control apparatus.

Fig. 6 is a diagram showing an example of a road condition.

Fig. 7 is a diagram showing a display in the road condition display area of the display when the road condition is in the condition as shown in fig. 6.

Fig. 8 is a functional block diagram of a processor of the ECU relating to display control of the road condition display area of the display.

Fig. 9 is a flowchart of the position determination processing of another vehicle that is not recognized by the laser radar by the 2 nd position determination unit.

Fig. 10 is a diagram showing a positional relationship between the host vehicle and another vehicle.

Description of the reference symbols

1 vehicle-mounted display system

11 laser radar

12 mm wave radar

13 outer camera of car

14 position finding sensor

15 storage device

20 display

21 ECU

Detailed Description

Hereinafter, embodiments will be described in detail with reference to the drawings. In the following description, the same reference numerals are assigned to the same components.

An in-vehicle display system 1 that displays a host vehicle and other vehicles around the host vehicle will be described with reference to fig. 1 and 2. Fig. 1 is a schematic diagram showing a configuration of an in-vehicle display system 1 according to an embodiment. Fig. 2 is a plan view of the vehicle 100 mounted with the in-vehicle display system 1.

The in-vehicle display system 1 is mounted on the vehicle 100, and displays various information on a display. In the present embodiment, the in-vehicle display system 1 includes a laser radar (Lidar)11, a millimeter wave radar 12, an outside-vehicle camera 13, a positioning sensor 14, a storage device 15, a display 20, and an electronic control unit (hereinafter referred to as "ECU") 21.

However, the in-vehicle display system 1 may not necessarily have all of these components. For example, the in-vehicle display system 1 may not necessarily include the vehicle exterior camera 13 as long as it includes the millimeter wave radar 12.

The laser radar 11, the millimeter wave radar 12, the exterior camera 13, the positioning sensor 14, the storage device 15, the display 20, and the ECU21 are communicably connected via the interior network 22. The in-vehicle Network 22 is a Network conforming to the standard of CAN (Controller Area Network) or the like.

The laser radar 11 is a distance measuring sensor that measures reflected light of laser light that emits light in a pulse shape and measures the position of an object located within a measurement range. Specific examples of the object include roads and obstacles (e.g., buildings, vehicles on roads, curbs, falling objects, pedestrians, etc.) located within the measurement range. As shown in fig. 2, the laser radar 11 is disposed at a front end portion (for example, in a front bumper) of the vehicle 100. However, the laser radar 11 may be disposed at a position different from the front end portion of the vehicle 100, or a plurality of laser radars 11 may be provided in the vehicle 100. The range in which the distance can be measured by the laser radar 11 is a range X (for example, about 100 m) indicated by a solid line in fig. 2. Therefore, in the present embodiment, the measurable range is shorter than the millimeter wave radar 12 and the vehicle exterior camera 13 described later.

Fig. 3 (a) and (B) are diagrams showing a method of measuring a distance to an object by the laser radar 11. As shown in fig. 3 (a), the laser radar 11 irradiates a line of laser beams arranged in the vertical direction at different vertical irradiation angles while scanning in the lateral direction (horizontal direction), and receives the reflected light of each irradiated laser beam. The laser radar 11 measures the distance to the object in the irradiation direction based on the time from the irradiation of the laser light until the reception of the reflected light. Specifically, as shown in fig. 3B, the laser radar 11 measures the distance to the object at each point of irradiation (reflection) of the laser beam, and generates point group data up to the object within the measurement range. Every time the laser radar 11 generates the dot group data, the generated dot group data is output to the ECU21 via the in-vehicle network 22. In addition, as long as the laser radar 11 can measure the position of the object by using the laser light, the distance to the object may be measured by another method.

The millimeter wave radar 12 is a distance measuring sensor that emits a radio wave having a wavelength of mm continuously in a pulse form or while modulating a frequency, measures a reflected wave of the radio wave, and measures a position of an object within a measurement range. Specific examples of the object include an obstacle in the measurement range. Therefore, the millimeter wave radar 12 functions as a peripheral vehicle position measurement device that detects the position of another vehicle around the vehicle 100. As shown in fig. 2, the millimeter wave radar 12 is disposed in a front end portion (for example, in a front bumper) of the vehicle 100. In particular, in the present embodiment, the millimeter wave radar 12 is disposed at the same position as the laser radar 11. However, the millimeter wave radar 12 may be disposed in a position different from the laser radar 11, or a plurality of millimeter wave radars 12 may be provided in the vehicle 100. The range in which the distance can be measured by the millimeter wave radar 12 is a range Y (for example, about 200 m) indicated by a one-dot chain line in fig. 2. Therefore, the range in which the millimeter wave radar 12 can measure is longer than the laser radar 11 and the vehicle exterior camera 13 described later.

The millimeter wave radar 12 transmits an electric wave from a transmitting antenna, and receives a reflected wave through a receiving antenna. The millimeter wave radar 12 measures the distance to the object based on the time from the transmission of the radio wave from the transmission antenna to the reception of the reflected wave. The millimeter wave radar 12 measures the direction of the object with respect to the millimeter wave radar 12 based on the variation in reception of the reflected wave between the plurality of receiving antennas arranged in line. The millimeter wave radar 12 mixes the radio wave transmitted from the transmission antenna and the reflected wave received by the reception antenna, and performs signal processing to generate data relating to the position information of the object. Every time the millimeter wave radar 12 generates data relating to the position information of the object, the generated data is output to the ECU21 via the in-vehicle network 22. Further, as long as the distance to the object can be measured by using radio waves, a radar to which radio waves of other wavelengths are applied may be used instead of the millimeter wave radar.

The vehicle exterior camera 13 is a device that photographs an object within a measurement range. Specific examples of the object include roads and obstacles within the measurement range. The exterior camera 13 includes: a two-dimensional detector (CCD, C-MOS, etc.) composed of an array of photoelectric conversion elements having sensitivity to visible light; and an imaging optical system that images an image of a region that becomes a photographic subject on the two-dimensional detector. In the present embodiment, the vehicle exterior camera 13 is attached to the vehicle interior of the vehicle 100 so as to face the front of the vehicle 100, for example, and is attached to the inside of the front glass as shown in fig. 2 in particular. However, the vehicle exterior camera 13 may be provided at a position different from the inner side of the front glass, or a plurality of vehicle exterior cameras 13 may be provided in the vehicle 100. A range that can be photographed by the vehicle exterior camera 13 with a certain degree of resolution is a range Z indicated by a broken line in fig. 2. Therefore, in the present embodiment, the measurable range is longer than the laser radar 11 and shorter than the millimeter wave radar 12.

The vehicle exterior camera 13 captures an image of a front area of the vehicle 100 at a predetermined capturing cycle (for example, 1/30 seconds to 1/10 seconds), and generates an image in which the front area is reflected. Each time the exterior camera 13 generates an image, the generated image is output to the ECU21 via the in-vehicle network 22. In addition, the exterior camera 13 may be a monocular camera or a stereo camera. When a stereo camera is used as the exterior camera 13, the exterior camera 13 also functions as a distance measuring sensor for measuring the position of the object. Therefore, in this case, the vehicle exterior camera 13 also functions as a peripheral vehicle position measurement device that detects the position of another vehicle around the vehicle 100. The vehicle 100 may be provided with a plurality of vehicle exterior cameras having different imaging directions or focal lengths.

The positioning sensor 14 is a sensor for measuring the position of the vehicle 100 itself. The Positioning sensor 14 is, for example, a GPS (Global Positioning System) receiver. The GPS receiver receives GPS signals from a plurality of GPS satellites, and measures the position of the vehicle 100 based on the received GPS signals. The positioning sensor 14 outputs the measurement result of the position of the vehicle 100 to the ECU21 via the in-vehicle network 22 at predetermined intervals. The positioning sensor 14 may be a receiver conforming to another satellite positioning system as long as it can measure the position of the vehicle 100 itself.

The storage device 15 includes, for example, a hard disk device or a nonvolatile semiconductor memory. The storage device 15 stores map information. The map information includes, for each predetermined section of the road, information indicating the position of the section and road signs (for example, lanes, scribe lines, or stop lines). The storage device 15 reads the map information in accordance with a request for reading the map information from the ECU21, and transmits the map information to the ECU21 via the in-vehicle network 22.

The display 20 is a display device that displays the vehicle 100 and information related to driving of the vehicle 100. In particular, in the present embodiment, the display 20 functions as a display device that displays a scribe line icon corresponding to a scribe line around the host vehicle and a vehicle icon corresponding to another vehicle around the host vehicle. The display 20 is a device that displays an image on a screen, such as a liquid crystal display or an organic EL display. Alternatively, the display 20 may be a head-up display that projects an image onto a transparent plate such as a window glass provided in front of the vehicle 100 in front of the driver. In any case, the display 20 may be any type of display as long as it can display an image. The display 20 is connected to the ECU21 via the in-vehicle network 22. The display 20 receives a display signal from the ECU21, and displays an image corresponding to the received display signal.

Fig. 4 is a diagram showing an example of a part of the display screen of the display 20. The display 20 is provided with a road condition display area 40 as shown in fig. 4, and a road condition schematically indicating the condition of the road mainly in front of the vehicle 100 is displayed in the road condition display area 40. Specifically, the display 20 displays an area line icon 42 corresponding to an area line on the road on which the vehicle (host vehicle) 100 is traveling, a host vehicle icon 41 corresponding to the vehicle 100, and another vehicle icon 43 corresponding to another vehicle around the vehicle 100. The display 20 may display information other than the road condition (for example, the speed of the vehicle, the temperature outside the vehicle, the current time, the shift position, the water temperature, the remaining fuel amount, various warnings, an energy consumption amount display, and the like) in an area other than the road condition display area 40.

The ECU21 controls the display of the display 20. In particular, in the present embodiment, the ECU21 functions as a display control device that controls the display of the dash-dot line icon 42 and the vehicle icons 41 and 43 on the display 20. Fig. 5 is a hardware configuration diagram of the ECU21 as one embodiment of the display control apparatus. The ECU21 has a communication interface 51, a memory 52, and a processor 53. The communication interface 51, the memory 52, and the processor 53 may be separate circuits or may be formed as one integrated circuit.

The communication interface 51 has a communication interface circuit and a device interface circuit. The communication interface circuit is a circuit for connecting the ECU21 to the in-vehicle network 22. The device interface circuit is a circuit for outputting a display signal to the display 20.

The communication interface 51 transmits the received point cloud data to the processor 53 every time point cloud data is received from the laser radar 11. In addition, the communication interface 51 transmits the received signal representing the position information to the processor 53 each time a signal representing the position information is received from the millimeter wave radar 12. Further, the communication interface 51 sends the received image to the processor 53 every time an image is received from the vehicle exterior camera 13. Each time the communication interface 51 receives the measurement result of its own position from the positioning sensor 14, it transmits the measurement result to the processor 53. The communication interface 51 transmits the map information read from the storage device 15 to the processor 53. Also, the communication interface 51 transmits the received display signal to the display 20 every time it receives the display signal to the display 20 from the ECU 21.

The memory 52 is a storage device that stores data. The memory 52 includes, for example, a volatile semiconductor memory and a nonvolatile semiconductor memory. The memory 52 stores a program of the driving assistance process executed by the processor 53 of the ECU 21. In addition, the memory 52 stores output data of the laser radar 11, the millimeter wave radar 12, and the vehicle exterior camera 13, various data used in display processing, and the like.

The processor 53 has one or more CPUs (Central Processing units) and peripheral circuits thereof. The processor 53 may further include another arithmetic circuit such as a logical operation unit or a numerical operation unit. The processor 53 executes display processing of the display 20 and controls display on the display 20. The processor 53 controls the display of the dash line icon 42 corresponding to the dash line around the own vehicle and the other vehicle icons 43 corresponding to the other vehicles around the own vehicle on the display 20.

< display >

Fig. 6 is a diagram showing an example of a road condition. Fig. 6 shows a road with two lanes on one side, which are defined by 3-row scribe lines 200. In the example shown in fig. 6, the host vehicle 100 travels in the left lane. In the road condition shown in fig. 6, two other vehicles 300 (the 1 st other vehicle 300a and the 2 nd other vehicle 300b) travel ahead of the own vehicle 100 in the same lane as the own vehicle 100, and one other vehicle 300 (the 3 rd other vehicle 300c) travels ahead of the own vehicle 100 in an adjacent lane of the own vehicle 100. In the following description, the other vehicle 300 (the 1 st other vehicle 300a in fig. 6) that runs ahead of the own vehicle 100 and immediately in front of the own vehicle 100 in the same lane as the own vehicle 100 is referred to as a preceding vehicle, and the other vehicle 300 (the 2 nd other vehicle 300b in fig. 6) that runs ahead of the preceding vehicle and immediately in front of the preceding vehicle is referred to as a preceding vehicle.

In particular, in the example shown in fig. 6, the 1 st another vehicle 300a is located within the measurement range of the laser radar 11 of the host vehicle 100. Since the position of laser radar 11 is measured with very high accuracy, the position of the 1 st other vehicle 300a can be measured relatively accurately.

On the other hand, the 2 nd other vehicle 300b is located forward of the 1 st other vehicle 300 a. Therefore, the 2 nd other vehicle 300b is hidden from view by the 1 st other vehicle 300a from the view of the own vehicle 100. Since the laser radar 11 can measure only the position of the object directly visible from the position of the laser radar 11, it is difficult to measure the position of the second another vehicle 300b by the laser radar 11. The 2 nd other vehicle 300b is located outside the measurement range of the laser radar 11. Therefore, it is also difficult to measure the position of the second another vehicle 300b by the laser radar 11.

On the other hand, the millimeter wave radar 12 may measure the position of an object that is not directly visible from the position of the millimeter wave radar 12, for example, by reflecting radio waves on the ground. The 2 nd other vehicle 300b is located within the measurement range of the millimeter wave radar 12 of the host vehicle 100. Therefore, millimeter wave radar 12 can measure the position of second another vehicle 300b of 2 nd whose position cannot be measured by laser radar 11. However, the accuracy of the position measurement by the millimeter wave radar 12 is lower than the accuracy of the position measurement by the laser radar 11. In particular, the accuracy of the measurement of the position in the left-right direction by millimeter wave radar 12 is lower than the accuracy of the measurement of the position in the left-right direction by laser radar 11. Therefore, the position of the 2 nd other vehicle 300b, particularly the position in the left-right direction, cannot be measured with such accuracy.

Further, the 3 rd other vehicle 300c traveling in the adjacent lane of the own vehicle 100 is also located outside the measurement range of the laser radar 11. Therefore, it is difficult to measure the position of the 3 rd other vehicle 300c by the laser radar 11. On the other hand, the 3 rd other vehicle 300c is located within the measurement ranges of the millimeter wave radar 12 and the vehicle exterior camera 13 of the own vehicle 100. Therefore, the position of the 3 rd other vehicle 300c can be measured by the millimeter wave radar 12 and the vehicle exterior camera 13. However, the accuracy of the measurement of the position by the vehicle exterior camera 13 is also lower than the accuracy of the measurement by the laser radar 11. Therefore, the position of the 3 rd other vehicle 300c cannot be measured as accurately as possible.

Fig. 7 is a diagram showing a display in the road condition display area 40 of the display 20 when the road condition is in the condition as shown in fig. 6. As shown in fig. 7, the display 20 displays a host vehicle icon 41 corresponding to the host vehicle 100, a scribe line icon 42 corresponding to the scribe line 200 on the road, and another vehicle icon 43 corresponding to another vehicle 300.

The own vehicle icon 41 is substantially always displayed at the same position on the display 20. In particular, in the present embodiment, the own vehicle icon 41 is displayed below the center of the road condition display area 40 of the display 20. The own vehicle icon 41 is displayed in a different color and a different form from the other vehicle icons 43.

The display position of the dashed-line icon 42 is determined based on the own position measured by the positioning sensor 14 and the map information stored in the storage device 15. Specifically, the relative position of the scribe line 200 around the own vehicle 100 with respect to the own vehicle 100 is determined based on the measured own position and the map information on the scribe line around the own position. Then, the scribe line icon 42 is displayed at the display position corresponding to the calculated relative position.

Further, the display position of the dashed-line icon 42 may also be determined based on an image captured by the vehicle exterior camera 13. In this case, the scribe lines reflected in the image are recognized by the image recognition processing. As the image recognition processing, a known pattern recognition method such as a neural network or a support vector machine can be used. Then, based on the position of the recognized scribe line in the image, the relative position of the scribe line 200 to the host vehicle 100 is calculated. Then, the scribe line icon 42 is displayed at the display position corresponding to the calculated relative position. The display position of the dashed-dotted line icon 42 may be determined based on both the output of the positioning sensor 14, the map information, and the image captured by the vehicle exterior camera 13.

The display position of the 1 st another vehicle icon 43a corresponding to the 1 st another vehicle 300a is determined based on the relative position of the 1 st another vehicle 300a with respect to the own vehicle 100 calculated from the point cloud data output from the laser radar 11. Therefore, the 1 st other vehicle icon 43a is displayed at the display position in the front-rear direction corresponding to the relative position in the front-rear direction determined based on the output of the laser radar 11. In addition, the 1 st other vehicle icon 43a is displayed at a display position in the left-right direction corresponding to the relative position in the left-right direction determined based on the output of the laser radar 11.

On the other hand, as described above, the position of the 2 nd other vehicle 300b is not measured by the laser radar 11, but is measured by the millimeter wave radar 12. Therefore, the display position of the 2 nd other-vehicle icon 43b corresponding to the 2 nd other vehicle 300b is basically determined based on the position information output from the millimeter wave radar 12. However, as described above, the measurement accuracy of the position in the left-right direction of the millimeter wave radar 12 is not so high.

Then, in the present embodiment, the relative position in the front-rear direction of the 2 nd other vehicle 300b with respect to the own vehicle 100 is calculated based on the output of the millimeter wave radar 12. Further, the 2 nd other vehicle icon 43b is displayed at the display position in the front-rear direction corresponding to the calculated relative position in the front-rear direction. On the other hand, when the display position in the left-right direction of the 2 nd other vehicle icon 43b is determined, the relative position in the left-right direction of the 2 nd other vehicle 300b with respect to the own vehicle 100 is calculated based on the output of the millimeter wave radar 12. Then, based on the relative position of the scribe line 200 calculated as described above, the relative position of the lane on the road in the region in the front-rear direction where the 2 nd other vehicle 300b is located with respect to the host vehicle 100 is calculated. The display position in the left-right direction of the 2 nd other vehicle icon 43b is determined based on the calculated relative position of the center of the lane and the relative position in the left-right direction of the 2 nd other vehicle 300b calculated based on the output of the millimeter wave radar 12. Specifically, in the present embodiment, the display position in the left-right direction of the 2 nd another vehicle icon 43b is set at the position at the center in the left-right direction of the lane closest to the relative position in the left-right direction of the 2 nd another vehicle 300b calculated based on the output of the millimeter wave radar 12.

The position of the 3 rd other vehicle 300c is also measured by the millimeter wave radar 12, not by the laser radar 11. Specifically, the relative position in the front-rear direction of the 3 rd other vehicle 300c with respect to the own vehicle 100 is calculated based on the output of the millimeter wave radar 12. Further, based on the relative position of the scribe line 200 calculated as described above, the relative position of the 3 rd other vehicle 300c with respect to the host vehicle 100 is calculated for each lane on the road in the region in the front-rear direction. The display position in the left-right direction of the 3 rd other vehicle icon 43c is determined based on the calculated relative position of the center of each lane and the relative position in the left-right direction of the 3 rd other vehicle 300c calculated based on the output of the millimeter wave radar 12. Specifically, in the present embodiment, the display position in the left-right direction of the 3 rd another vehicle icon 43c is set at the position at the center in the left-right direction of the lane closest to the relative position in the left-right direction of the 3 rd another vehicle 300c calculated based on the output of the millimeter wave radar 12.

As described above, in the present embodiment, the other vehicle 300 whose position information can be measured by the laser radar 11 displays the corresponding other vehicle icon 43 based on the position information measured by the laser radar 11. On the other hand, with respect to another vehicle 300 whose position information cannot be measured by the laser radar 11, the other vehicle icon 43 is displayed based on the position information in the front-rear direction measured by the millimeter wave radar 12 and the position information of the scribe line (or the lane).

In the above embodiment, the 2 nd another vehicle icon 43b and the 3 rd another vehicle icon 43c are both displayed in the center of the lane. However, the other vehicle icons corresponding to the other vehicles whose positions have been specified by the peripheral vehicle position measurement device other than the laser radar may not necessarily be displayed in the center of the lane as long as the other vehicle icons are controlled within the lane.

In the above-described embodiment, when the position information cannot be measured by the laser radar, the corresponding another-vehicle icon 43 is displayed based on the position information of the another vehicle 300 measured by the millimeter wave radar 12. In this case, however, the corresponding another-vehicle icon 43 may be displayed based on the position information of the another vehicle 300 measured by a device other than the millimeter-wave radar 12. Specifically, for example, the position information of the another vehicle 300 is calculated based on the image captured by the vehicle exterior camera 13, and the corresponding another vehicle icon 43 is displayed based on the calculated position information.

< display control >

Fig. 8 is a functional block diagram of the processor 53 of the ECU21 relating to display control of the road condition display area 40 of the display 20. The processor 53 has a laser radar vehicle determining section 61, a radar vehicle determining section 62, a scribe line position determining section 63, an unidentified vehicle determining section 64, a 1 st position determining section 65, a 2 nd position determining section 66, and a display section 67. These functional blocks that the processor 53 has are, for example, functional modules realized by a computer program that operates on the processor 53. Alternatively, these functional blocks included in the processor 53 may be dedicated arithmetic circuits provided in the processor 53.

The laser radar vehicle specifying unit 61 specifies the position of another vehicle 300 around the host vehicle 100 based on the output of the laser radar 11. For example, the point group data output from the laser radar 11 is input to the laser radar vehicle specifying unit 61. The laser radar vehicle specifying unit 61 performs recognition processing based on the point group data, and thereby recognizes the other vehicles 300 around the host vehicle 100 from the point group data. Specifically, the laser radar vehicle specifying unit 61 groups the point group data into groups of data having equal distances, for example, and groups the related groups into groups representing the target object by aggregating the groups. Each of the target object groups thus collected corresponds to a certain object around the own vehicle 100. The laser radar vehicle specifying unit 61 extracts a group of target objects corresponding to the other vehicle 300 among the target objects, and identifies the other vehicle 300 around the host vehicle 100. Then, based on the center position of the target object group corresponding to each of the identified other vehicles 300, the position of the other vehicle 300 corresponding to the target object group is determined. Specifically, the laser radar vehicle specifying unit 61 specifies the relative position of each other vehicle 300 with respect to the host vehicle 100 in the front-rear direction and the relative position of each other vehicle 300 with respect to the host vehicle 100 in the left-right direction. The laser radar vehicle specifying unit 61 inputs the specified positions of the other vehicles 300 to the unidentified vehicle specifying unit 64 and the 1 st position specifying unit 65.

The radar-vehicle determining section 62 determines the positions of other vehicles 300 around the own vehicle 100 based on the output of the millimeter wave radar 12. Data relating to the position information output from the millimeter wave radar 12, for example, is input to the radar vehicle determination section 62. The radar vehicle specifying unit 62 performs recognition processing to recognize another vehicle 300 around the host vehicle 100 based on data relating to the position information. And, based on the data corresponding to the identified other vehicle 300, the location of the identified other vehicle 300 is determined. Specifically, the radar vehicle specifying unit 62 specifies the relative position of each other vehicle 300 with respect to the own vehicle 100 in the front-rear direction and the relative position of each other vehicle 300 with respect to the own vehicle 100 in the left-right direction. The radar vehicle determination section 62 inputs the determined relative position of the other vehicle 300 to the unidentified vehicle determination section 64.

In the present embodiment, the radar-vehicle specifying unit 62 specifies the position of the other vehicle 300 around the own vehicle 100 based on the output of the millimeter wave radar 12. However, instead of the radar vehicle specifying unit 62, a vehicle specifying unit that specifies the position of the other vehicle 300 based on the output of a device other than the laser radar 11 different from the millimeter wave radar 12 may be provided. Specifically, for example, a camera vehicle specifying unit that specifies the position of another vehicle 300 around the host vehicle 100 based on the output of the vehicle exterior camera 13 may be provided.

The dash line position determination section 63 determines the position of the dash line 200 around the own vehicle 100. For example, the own position of the vehicle 100 measured by the positioning sensor 14 and the map information stored in the storage device 15 are input to the dividing line position specifying unit 63. The scribe line position determination unit 63 determines the scribe line located around the position of the vehicle 100 on the basis of the map information of the road on which the vehicle 100 is traveling. Then, the dash line position determination unit 63 determines the relative position of the determined dash line 200 with respect to the own vehicle 100. The scribe line position determining section 63 inputs the determined relative position of the scribe line 200 to the 2 nd position determining section 66. Then, the scribe line position specifying unit 63 specifies the specified relative position of the scribe line 200 as the display position of the scribe line icon 42 corresponding to the scribe line 200. The scribe line position specification unit 63 inputs the specified display position of the scribe line icon 42 to the display unit 67.

Alternatively, the scribe line position specifying unit 63 may specify the position of the scribe line 200 based on an image captured by the vehicle exterior camera 13. In this case, for example, an image captured by the vehicle exterior camera 13 is input to the scribe line position determination unit 63. The lane line position specifying unit 63 recognizes a lane line of a road on which the host vehicle 100 is traveling by image recognition processing, and specifies a relative position of a lane line around the vehicle 100 based on the recognized lane line. Then, the scribe line position specifying unit 63 specifies the specified relative position of the scribe line 200 as the display position of the scribe line icon 42 corresponding to the scribe line 200.

The unidentified vehicle determination section 64 determines another vehicle 300 whose position is not determined by the laser radar vehicle determination section 61, among other vehicles 300 around the own vehicle 100 whose position is determined by the radar vehicle determination section 62. The position of the other vehicle 300 determined by the laser radar vehicle determination section 61 and the position of the other vehicle 300 determined by the radar vehicle determination section 62 are input to the unidentified vehicle determination section 64. The unidentified vehicle determination unit 64 determines, based on the position of the other vehicle 300 that is input, another vehicle 300, of the plurality of other vehicles 300 determined by the radar vehicle determination unit 62, around which the other vehicle 300 determined by the lidar vehicle determination unit 61 does not exist. The unidentified vehicle identification unit 64 identifies the other vehicle 300 thus identified as the other vehicle 300 whose position is not identified by the lidar vehicle identification unit 61 (hereinafter referred to as "another vehicle unidentified by lidar"). The unidentified vehicle determination section 64 inputs the determined relative position of the other vehicle 300 that is unidentified by the laser radar to the 2 nd position determination section 66.

The 1 st position specifying unit 65 specifies the display position of the another-vehicle icon 43 corresponding to the another vehicle 300 whose position is measured by the laser radar 11. The position of the other vehicle 300 specified by the laser radar vehicle specifying unit 61 is input to the 1 st position specifying unit 65. The 1 st position specifying unit 65 specifies the display position corresponding to the relative position in the front-rear direction of the other vehicle 300 with respect to the own vehicle 100 specified by the laser radar vehicle specifying unit 61 as the display position in the front-rear direction of the other vehicle icon 43 corresponding to the other vehicle 300. Then, the 1 st position specifying unit 65 specifies a position corresponding to the relative position in the left-right direction of the other vehicle 300 with respect to the own vehicle 100 specified by the laser radar vehicle specifying unit 61 as the display position in the left-right direction of the other vehicle icon 43 corresponding to the other vehicle 300. The 1 st position specifying unit 65 inputs the specified display position of the another vehicle icon 43 to the display unit 67.

The 2 nd position specifying unit 66 specifies the display position of the another vehicle icon 43 corresponding to the another vehicle 300 whose position is not measured by the laser radar 11. The relative position of the other vehicle 300 that is not recognized by the laser radar determined by the unidentified vehicle determination section 64 and the relative position of the scribe line 200 determined by the scribe line position determination section 63 are input to the 2 nd position determination section 66. The 2 nd position specifying unit 66 estimates the position in the left-right direction in the lane closest to the position in the left-right direction of the other vehicle 300 based on the relative position in the front-rear direction of the other vehicle 300 not recognized by the laser radar, the relative position in the left-right direction of the other vehicle 300 not recognized by the laser radar, and the relative position of the scribe line 200.

Fig. 9 is a flowchart of the position determination processing of another vehicle 300 that is not recognized by the laser radar by the 2 nd position determining unit 66. As shown in fig. 9, the 2 nd position specifying unit 66 first obtains the relative position of the another vehicle 300 that is not recognized by the laser radar specified by the unidentified vehicle specifying unit 64 (step S11). Next, the 2 nd position specifying unit 66 acquires the relative position of the scribe line 200 specified by the scribe line position specifying unit 63 (step S12).

Then, the 2 nd position specifying unit 66 calculates the center position in the left-right direction of the lane in which the other vehicle 300 is traveling, based on the acquired relative position (the relative position in the front-rear direction and the relative position in the left-right direction) of each other vehicle 300 that is not recognized by the laser radar and the relative position of the scribe line 200 (step S13). Specifically, the center position in the left-right direction of the plurality of lanes (the travel lane of the host vehicle 100 and the other lane having the same traveling direction as the travel lane) of the acquired relative position in the front-rear direction of the other vehicle 300 is calculated. The 2 nd position specifying unit 66 specifies, as the center position in the left-right direction of the lane in which the other vehicle 300 is traveling, the center position of the lane in which the center position in the plurality of lanes is located closest to the acquired position in the left-right direction of the other vehicle 300.

Next, the 2 nd position determining part 66 determines whether or not the center position in the left-right direction of the other vehicle 300 determined by the unidentified vehicle determining part 64 is within a predetermined reference distance from the center position in the left-right direction of the corresponding lane determined in step S13 (step S14). The reference distance is set to a distance equal to or less than half the width of each lane. If it is determined in step S14 that the determined center position in the left-right direction of each other vehicle 300 is within the reference distance from the center position in the left-right direction of the corresponding lane, the 2 nd position determining unit 66 determines the position in the left-right direction of the other vehicle 300 determined by the unidentified vehicle determining unit 64 as the display position in the left-right direction of the other vehicle icon 43 corresponding to the other vehicle 300 (step S15). On the other hand, if it is determined in step S14 that the center position in the left-right direction of each other vehicle 300 that has been specified is farther than the reference distance from the center position in the left-right direction of the corresponding lane, the 2 nd position specifying unit 66 specifies the center position in the left-right direction of the corresponding lane as the display position in the left-right direction of the other vehicle icon 43 corresponding to the other vehicle 300 (step S16). The 2 nd position specifying unit 66 specifies the position in the front-rear direction of the another vehicle 300 specified by the unidentified vehicle specifying unit 64 as the display position in the front-rear direction of the another vehicle icon 43 corresponding to the another vehicle 300 (step S17). The display position in the left-right direction and the display position in the front-rear direction of each of the other vehicles 300 thus specified by the 2 nd position specifying unit 66 are input to the display unit 67.

The display unit 67 outputs a display signal to the display 20. The display position of the other vehicle icon 43 determined by the 1 st position determining section 65, the display position of the other vehicle icon 43 determined by the 2 nd position determining section 66, and the relative position of the ruled line 200 determined by the ruled line position determining section 63 are input to the display section 67. The display section 67 determines the display position of the scribe line 200 based on the relative position of the scribe line 200 determined by the scribe line position determination section 63. Then, the display unit 67 outputs a display signal to the display 20 to display each of the other vehicle icons 43 and the scribe line 200 at the determined display position. The display unit 67 outputs a display signal to the display 20 so that the own vehicle icon 41 is always displayed at the same position. As a result, the display 20 displays the image as shown in fig. 4 and 7.

< Effect >

As described above, the laser radar 11 can determine its position only for other vehicles that can be directly seen from the position of the laser radar 11. Further, since the measurement range of the laser radar 11 is relatively short, the position of another vehicle traveling far away cannot be measured. For this reason, for the measurement of the position of the other vehicle, a measurement device different from laser radar 11, such as millimeter-wave radar 12, may be used. However, the accuracy of measuring the position of the measurement device such as the millimeter wave radar 12 is lower than the accuracy of measuring the position of the laser radar 11. Therefore, when the other-vehicle icon 43 is displayed on the display 20 by directly using the measurement data of the position of the other vehicle 300 of the measurement device such as the millimeter-wave radar 12, the position of the other-vehicle icon 43 is displayed in a shaken manner, and the other-vehicle icon 43 cannot be displayed at an appropriate display position.

In contrast, according to the in-vehicle display system according to the above-described embodiment, the 2 nd position specifying unit 66 specifies the display position in the front-rear direction corresponding to the position in the front-rear direction of the other vehicle 300 measured by the peripheral vehicle position measuring device other than the laser radar 11 and the display position in the left-right direction corresponding to the position in the left-right direction in the lane where the other vehicle is traveling as the display position of the other vehicle icon 43 corresponding to the other vehicle 300. That is, in the present embodiment, another vehicle 300 recognized by a measurement device such as the millimeter wave radar 12 is displayed in the center of the corresponding lane. As a result, the other-vehicle icon 43 corresponding to the other vehicle 300 recognized by the measurement device such as the millimeter wave radar 12 is displayed without being shaken, and thus the other-vehicle icon 43 can be displayed at an appropriate display position.

Further, since there is a preceding vehicle between the preceding vehicle and the host vehicle 100, the position of the preceding vehicle cannot be substantially measured by the laser radar 11. Therefore, the preceding vehicle basically measures its position by the millimeter wave radar 12 as a peripheral vehicle position measuring device other than the laser radar 11. Therefore, the display control device of the in-vehicle display system according to the present embodiment can be said to be such that when the position of the preceding vehicle running in the same lane ahead of the host vehicle 100 and the position of the preceding vehicle running in the same lane ahead of the preceding vehicle are determined by the nearby vehicle position measuring device, another vehicle icon corresponding to the preceding vehicle is displayed at a display position in the front-rear direction and in the left-right direction corresponding to a position in the front-rear direction and in the left-right direction of the preceding vehicle specified by the peripheral vehicle position measurement device, and another vehicle icon corresponding to the preceding vehicle is displayed at a display position in the front-rear direction corresponding to a position in the front-rear direction of the preceding vehicle specified by the peripheral vehicle position measurement device and a display position in the left-right direction corresponding to a position in the left-right direction in a lane in which the preceding vehicle is traveling.

< modification >

While the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims.

For example, the 2 nd position specifying unit 66 may specify the relative position in the left-right direction of the another vehicle 300 that is not recognized by the laser radar based on the image of the another vehicle 300 captured by the vehicle exterior camera 13. A method of determining the relative position in the left-right direction of another vehicle 300 in this case will be described with reference to fig. 10.

Fig. 10 is a diagram showing a positional relationship between the host vehicle 100 and another vehicle 300 that is not recognized by the laser radar. When the host vehicle 100 and the other vehicle 300 are in the positional relationship as shown in fig. 10, the other vehicle 300 is shown in a state in which the traveling direction is inclined in the image captured by the vehicle exterior camera 13. The 2 nd position specifying unit 66 calculates the angle θ of the traveling direction of the other vehicle 300 with respect to the traveling direction of the host vehicle 100 based on the image of the 2 nd other vehicle captured by the vehicle exterior camera 13 by the image recognition processing. In addition, the relative position of the other vehicle 300 that is not recognized by the laser radar is input from the unidentified vehicle specifying unit 64 to the 2 nd position specifying unit 66. Therefore, the distance D in the front-rear direction from the host vehicle 100 to the other vehicle 300 is input to the 2 nd position specifying unit 66.

When it is assumed that the curvature radius R of the road on which the host vehicle 100 and the other vehicle 300 are traveling is constant between the host vehicle 100 and the other vehicle 300, the curvature radius R of the road is represented by the following formula (1). The distance y in the left-right direction between the host vehicle 100 and the other vehicle 300 is expressed by the following equation (2).

R＝D/tanθ…(1)

y＝R(1－cosθ)…(2)

That is, in the present modification, the relative position of the other vehicle 300 in the left-right direction with respect to the own vehicle 100 is determined based on the relative angle of the other vehicle 300 with respect to the own vehicle 100 and the relative position of the other vehicle 300 in the front-rear direction with respect to the own vehicle. In the present modification, the 2 nd position specifying unit 66 determines whether or not the relative position in the left-right direction of the other vehicle 300 specified by the unidentified vehicle specifying unit 64 is within a predetermined reference distance from the relative position in the left-right direction of the other vehicle 300 thus specified, in the same manner as in step S14 of fig. 9. When the distance is within the reference distance, the relative position in the left-right direction of the another vehicle 300 determined using the relative angle is determined as the display position in the left-right direction of the another vehicle icon 43 corresponding to the another vehicle 300. On the other hand, when the distance is longer than the reference distance, the center position in the left-right direction of the corresponding lane is determined as the display position in the left-right direction of the another-vehicle icon 43 corresponding to the another vehicle 300, as in step S16.

Further, when the own vehicle 100 makes a lane change, the position in the left-right direction of the other vehicle 300 cannot be appropriately calculated. Therefore, in the present modification, when the host vehicle 100 changes lanes, the 2 nd position specifying unit 66 specifies, as the display position of the another vehicle icon corresponding to the another vehicle 300, the display positions in the front-rear direction and the left-right direction corresponding to the positions in the front-rear direction and the left-right direction of the another vehicle 300 measured by the nearby vehicle position measuring device.