Periphery monitoring device and periphery monitoring method

Abstract

To provide a periphery monitoring device and a periphery monitoring method that can more reliably alert a driver to an obstacle even during driving support.SOLUTION: A periphery monitoring device of an embodiment monitors a periphery of a vehicle having a sensor which collects peripheral information, wherein a display control unit: displays a first mark including a first pointer pointing to an obstacle, a first signal disposed within the first pointer, and a second signal disposed around the first pointer, superimposed on the obstacle in a peripheral image; displays a second mark including a second pointer of the same color as the first pointer, superimposed on a ground position of the obstacle in an overhead image; dynamically displays the first signal such that a transparency of the first signal changes periodically; and dynamically displays the second signal such that the second signal rotates around the first pointer.SELECTED DRAWING: Figure 4A

Description

[Technical Field]

[0001] The present invention relates to a periphery monitoring device and a periphery monitoring method. [Background technology]

[0002] There are driving assistance devices that provide driving assistance when parking and leaving a vehicle. The driving assistance device calculates the vehicle's route to entering (parking) or leaving the vehicle and presents it to the driver. While the vehicle is moving, sensors attached to the vehicle detect obstacles around the vehicle and monitor the surroundings, for example, visually alerting the driver. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-161060 [Patent Document 2] Japanese Patent Application Publication No. 2017-129896 [Patent Document 3] Japanese Patent Application Publication No. 2017-122453 [Patent Document 4] Japanese Patent Application Publication No. 2018-148597 [Patent Document 5] Japanese Patent Application Laid-Open No. 2015-187806 Summary of the Invention [Problem to be solved by the invention]

[0004] Periphery monitoring technology involves marking obstacles with colors such as yellow or red to make them more visible. However, during complex driving operations such as entering or leaving a parking lot, it can be difficult to determine whether an obstacle is present while paying attention to the display device inside the vehicle.

[0005] The present invention has been made in view of the above, and provides a surroundings monitoring device and a surroundings monitoring method that can more reliably alert the driver to obstacles even during driving assistance. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a periphery monitoring device of an embodiment is a periphery monitoring device that monitors the periphery of a vehicle having a sensor that collects periphery information, and is equipped with a detection unit that detects obstacles around the vehicle based on the periphery information from the sensor when a user of the vehicle issues an instruction to start driving assistance to assist in parking or leaving the vehicle, and a display control unit that displays a periphery image of the vehicle including the obstacle and an overhead image on a display device inside the vehicle, wherein the display control unit displays a first mark including a first pointer pointing to the obstacle, a first signal located within the first pointer, and a second signal located around the first pointer, superimposed on the obstacle in the periphery image, displays a second mark including a second pointer of the same color as the first pointer, superimposed on the ground position of the obstacle in the overhead image, dynamically displays the first signal so that the transparency of the first signal changes periodically, and dynamically displays the second signal so that the second signal rotates around the first pointer.

[0007] With this configuration, it is possible to more reliably alert the driver to obstacles even during driving assistance.

[0008] In addition, in the above-described periphery monitoring device, when there are multiple obstacles, the detection unit calculates the order of closest distance to the vehicle for each of the obstacles, and the display control unit displays the first mark in a first color for the obstacle closest to the vehicle in the periphery image and dynamically displays the first and second signals, and displays the first mark in a color different from the first color for each obstacle except for the obstacle closest to the vehicle in the periphery image, statically displays the first signal without changing its transparency, and statically displays the second signal without rotating. This configuration makes it possible to make the obstacle closest to the vehicle stand out more than other obstacles.

[0009] In the above-described surroundings monitoring device, the display device is provided on the instrument panel of the vehicle. With this configuration, even an image on the display device provided on the instrument panel can visually highlight obstacles and draw the driver's attention.

[0010] In the above-described surroundings monitoring device, the surroundings image is an image of the area ahead in the direction of travel of the vehicle. With this configuration, whether the vehicle is moving forward or backward, an image of the area ahead in the direction of travel of the vehicle can be displayed and obstacles on the image can be marked to alert the driver.

[0011] A periphery monitoring method according to an embodiment is a periphery monitoring method for monitoring the periphery of a vehicle having a sensor that collects periphery information. When a user of the vehicle issues an instruction to start driving assistance to assist in parking or leaving the vehicle, the method detects obstacles around the vehicle based on the periphery information from the sensor, and displays a peripheral image of the vehicle including the obstacle and an overhead image on a display device within the vehicle. The display device displays a first mark including a first pointer pointing to the obstacle, a first signal located within the first pointer, and a second signal located around the first pointer, superimposed on the obstacle in the peripheral image, and a second mark including a second pointer of the same color as the first pointer, superimposed on the ground position of the obstacle in the overhead image. The first signal is dynamically displayed so that the transparency of the first signal changes periodically, and the second signal is dynamically displayed so that the second signal rotates around the first pointer.

[0012] With this configuration, it is possible to more reliably alert the driver to obstacles even during driving assistance. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a top view of a vehicle equipped with a driving assistance device according to an embodiment. [Figure 2] FIG. 2 is a block diagram illustrating an example of the overall configuration of the driving assistance system according to the embodiment. [Figure 3] FIG. 3 is a block diagram illustrating an example of a functional configuration of the driving assistance device according to the embodiment. [Figure 4A] FIG. 4A is a schematic diagram illustrating an example of a display on the monitor device during parking assistance by the driving assistance device according to the embodiment. [Figure 4B] FIG. 4B is a schematic diagram illustrating an example of a display on the monitor device during parking assistance by the driving assistance device according to the embodiment. [Figure 4C]FIG. 4C is a schematic diagram illustrating an example of a display on the monitor device during parking assistance by the driving assistance device according to the embodiment. [Figure 5] FIG. 5 is a flowchart illustrating an example of a procedure of a driving assistance process performed by the driving assistance device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Similar components in the following exemplary embodiments will be given the same reference numerals, and duplicated descriptions will be omitted as appropriate.

[0015] (Example of vehicle configuration) 1 is a top view of a vehicle 10 equipped with a driving assistance device 20 according to an embodiment. The front, rear, left and right of the vehicle 10 in FIG. 1 indicate directions when viewed from the driver's seat of the vehicle 10.

[0016] The vehicle 10 of the embodiment may be, for example, an internal combustion engine vehicle using an internal combustion engine as a power source, an electric vehicle or fuel cell vehicle using an electric motor as a power source, or a hybrid vehicle using both of these as a power source.

[0017] The vehicle 10 can be equipped with various transmissions and various systems, parts, and other devices required to drive the internal combustion engine or electric motor. The type, number, and layout of the devices related to driving the wheels 13 of the vehicle 10 can be set in various ways.

[0018] 1, a vehicle 10 includes a body 12, a plurality of wheels 13, a plurality of distance measuring units 14a-14l, and a plurality of imaging units 16a-16d. When it is not necessary to distinguish between the distance measuring units 14a-14l, they will be simply referred to as distance measuring unit 14. When it is not necessary to distinguish between the imaging units 16a-16d, they will be simply referred to as imaging unit 16.

[0019] The vehicle body 12 forms a vehicle cabin in which passengers ride. The vehicle body 12 is equipped with a plurality of wheels 13, a plurality of distance measuring units 14, and a plurality of image capturing units 16. In the example of FIG. 1, the vehicle body 12 is equipped with four wheels 13, twelve distance measuring units 14, and four image capturing units 16. However, the number of distance measuring units 14 and image capturing units 16 attached to the vehicle body 12 is arbitrary.

[0020] Four wheels 13 are provided on the front, rear, left and right sides of the vehicle body 12. The two front wheels 13 function as steering wheels, for example, and the two rear wheels 13 function as driving wheels, for example.

[0021] The distance measuring unit 14 as a sensor is, for example, a sonar that is provided on the outer periphery of the vehicle 10 and transmits sound waves such as ultrasonic waves as detection waves and captures the detection waves reflected by objects such as obstacles present around the vehicle 10. Note that the distance measuring unit 14 may also be a radar that transmits detection waves such as laser light, a millimeter wave radar, or the like.

[0022] The distance measuring unit 14 collects surrounding information, which is information about the surroundings of the vehicle 10, and outputs it to the driving assistance device 20. The distance measuring unit 14 collects, for example, a response time, which is the time from transmitting a detection wave to receiving it, as surrounding information for identifying the distance between an object and the vehicle 10. Based on the surrounding information collected by the distance measuring unit 14, the driving assistance device 20 can detect the presence or absence of obstacles, etc., around the vehicle 10 and the distance to those obstacles.

[0023] In addition, if the distance measuring unit 14 receives multiple detection waves reflected from multiple points on the object in response to a single transmission of a detection wave, the distance measuring unit 14 may include only the response time of the earliest received detection wave in the surrounding information.

[0024] Distance measuring units 14a to 14d are provided at the front of vehicle body 12. Of these distance measuring units 14a to 14d, distance measuring units 14b and 14c are also called front sonars and are provided at the front end of vehicle 10. Distance measuring units 14b and 14c detect objects ahead of vehicle 10 and collect information about the surroundings ahead of vehicle 10. Distance measuring units 14a and 14d are also called corner sonars and are provided at the corners of the front of vehicle 10. Distance measuring units 14a and 14d detect objects ahead of and on the outside of vehicle 10 and collect information about the surroundings ahead of vehicle 10.

[0025] The distance measuring units 14e to 14h are provided at the rear of the vehicle body 12. Of these distance measuring units 14e to 14h, the distance measuring units 14f and 14g are also called rear sonars and are provided at the rear end of the vehicle 10. The distance measuring units 14f and 14g detect objects behind the vehicle 10 and collect information about the surroundings behind the vehicle 10. The distance measuring units 14e and 14h are also called corner sonars and are provided at the corners of the rear of the vehicle 10. The distance measuring units 14e and 14h detect objects on the outside behind the vehicle 10 and collect information about the surroundings behind the vehicle 10.

[0026] The distance measuring units 14i to 14l are also called side sonars and are provided on the sides of the vehicle body 12. Of the distance measuring units 14i to 14l, the distance measuring units 14i and 14j are provided on the front sides of the vehicle 10. The distance measuring units 14k and 14l are provided on the rear sides of the vehicle 10. The distance measuring units 14i to 14l detect objects on the sides of the vehicle 10 and collect peripheral information on the sides of the vehicle 10.

[0027] The imaging unit 16 as a sensor is a digital camera incorporating an imaging element such as a CCD (Charge Coupled Device) or a CIS (CMOS Image Sensor). The imaging unit 16 generates a moving image including a plurality of frame images captured at a predetermined frame rate, or a still image.

[0028] The imaging units 16 are provided on the outer periphery of the vehicle body 12, each having a wide-angle lens or a fisheye lens, and are capable of capturing images in a range of, for example, 140° to 190° in the horizontal direction. The optical axis of the imaging units 16 is set to face diagonally downward.

[0029] As a result, the imaging unit 16 collects surrounding information by capturing images of the surroundings of the vehicle 10, including the road surface, and outputs the collected information to the driving assistance device 20. The driving assistance device 20 can detect the presence or absence of obstacles, etc., around the vehicle 10 and the positions of those obstacles based on the surrounding information collected by the imaging unit 16. Furthermore, the driving assistance device 20 can detect parking spaces around the vehicle 10 and the positions of those parking spaces based on the surrounding information collected by the imaging unit 16.

[0030] The imaging unit 16a is provided in the center in the left-right direction of the front end of the vehicle body 12, for example, on the front bumper. The imaging unit 16a collects captured images of the area in front of the vehicle 10 as peripheral information. The imaging unit 16b is provided in the center in the left-right direction of the rear end of the vehicle body 12, for example, on the rear bumper. The imaging unit 16b collects captured images of the area behind the vehicle 10 as peripheral information.

[0031] The imaging unit 16c is provided in the center in the longitudinal direction of the left end of the vehicle body 12, for example, on the left side mirror. The imaging unit 16c collects captured images of the left side of the vehicle 10 as peripheral information. The imaging unit 16d is provided in the center in the longitudinal direction of the right end of the vehicle body 12, for example, on the right side mirror. The imaging unit 16d collects captured images of the surroundings to the right of the vehicle 10 as peripheral information.

[0032] (Example of configuration of a driving assistance system) 2 is a block diagram showing an example of the overall configuration of a driving assistance system 200 according to an embodiment. The driving assistance system 200 is mounted on, for example, a vehicle 10, and provides driving assistance to the driver when the vehicle 10 is entering (parking) a parking space or leaving the parking space.

[0033] 2, the driving assistance system 200 includes a driving assistance device 20, a monitor device 30, a braking system 140, an acceleration system 150, a steering system 160, a gear shift system 170, a vehicle speed sensor 183, a distance measurement unit 14, and an imaging unit 16. These components are connected via an in-vehicle network NT so that they can send and receive information to and from each other.

[0034] The in-vehicle network NT includes, for example, a controller area network (CAN) and a local interconnect network (LIN), etc. The in-vehicle network NT may be included as part of the driving assistance system 200.

[0035] The driving assistance device 20 is configured as a microcomputer such as an ECU (Electronic Control Unit), and assists the driver in driving the vehicle 10.

[0036] The driving assistance device 20 includes a CPU (Central Processing Unit) 21, a display control circuit 23, an SSD (Solid State Drive) 24, a ROM (Read Only Memory) 25, and a RAM (Random Access Memory) 26. The CPU 21, the ROM 25, and the RAM 26 may be integrated in the same package.

[0037] The CPU 21 is an example of a hardware processor, and reads out a program stored in a nonvolatile storage device such as the ROM 25, and executes various types of arithmetic processing and control in accordance with the program.

[0038] The ROM 25 stores various programs and parameters necessary for executing the programs. The RAM 26 temporarily stores various data used in calculations by the CPU 21. The SSD 24 is a rewritable nonvolatile storage device that maintains data even when the power to the driving assistance device 20 is turned off.

[0039] Among the arithmetic processing performed by the driving assistance device 20, the display control circuit 23 mainly performs image processing of images obtained by the imaging unit 16 and data conversion of images to be displayed on the display unit 31 described below that is provided in the monitor device 30.

[0040] The braking system 140 includes a braking unit 141 , a braking control unit 142 , and a braking unit sensor 143 , and controls the deceleration of the vehicle 10 .

[0041] The braking unit 141 is a device including, for example, a brake and a brake pedal, and decelerates the vehicle 10. The braking control unit 142 is, for example, a microcomputer having a hardware processor such as a CPU. The braking control unit 142 decelerates the vehicle 10 based on the operation of the brake pedal, etc. by the driver. The braking unit sensor 143 is, for example, a position sensor, and detects the position of the brake pedal included in the braking unit 141. The braking unit sensor 143 outputs the detected brake pedal position to the in-vehicle network NT.

[0042] The acceleration system 150 includes an acceleration unit 151 , an acceleration control unit 152 , and an acceleration sensor 153 , and controls the acceleration of the vehicle 10 .

[0043] The acceleration unit 151 is a device including, for example, an accelerator pedal and the like, and accelerates the vehicle 10. The acceleration control unit 152 is, for example, a microcomputer having a hardware processor such as a CPU. The acceleration control unit 152 accelerates the vehicle 10 based on the operation of the accelerator pedal and the like by the driver. The acceleration sensor 153 is, for example, a position sensor, and detects the position of the accelerator pedal included in the acceleration unit 151. The acceleration sensor 153 outputs the detected accelerator pedal position to the in-vehicle network NT.

[0044] The steering system 160 has a steering unit 161, a steering control unit 162, and a steering unit sensor 163, and controls the direction of travel of the vehicle 10.

[0045] The steering unit 161 is a device including, for example, a steering wheel or a like device, and steers the steered wheels of the vehicle 10 to steer the traveling direction of the vehicle 10. The steering control unit 162 is, for example, a microcomputer having a hardware processor such as a CPU. The steering control unit 162 controls the traveling direction of the vehicle 10 based on the operation of the steering wheel or the steering wheel by the driver. The steering unit sensor 163 is, for example, an angle sensor including a Hall element or a like device, and detects the steering angle, which is the rotation angle of the steering unit 161. The steering unit sensor 163 outputs the detected steering angle of the steering unit 161 to the in-vehicle network NT.

[0046] The transmission system 170 has a transmission unit 171, a transmission control unit 172, and a transmission unit sensor 173, and controls the gear ratio of the vehicle 10.

[0047] The transmission unit 171 is a device including, for example, a shift lever and the like, and changes the gear ratio of the vehicle 10. The transmission control unit 172 is, for example, a microcomputer having a hardware processor such as a CPU. The transmission control unit 172 controls the gear ratio of the vehicle 10 based on the operation of the shift lever and the like by the driver. The transmission unit sensor 173 is, for example, a position sensor, and detects the position of the shift lever included in the transmission unit 171. The transmission sensor 173 outputs the detected position of the shift lever to the in-vehicle network NT.

[0048] The vehicle speed sensor 183 has, for example, a Hall element provided near the wheel 13 of the vehicle 10, and detects the amount of rotation or the number of rotations per unit time of the wheel 13. The vehicle speed sensor 183 outputs the number of wheel speed pulses indicating the detected amount of rotation or number of rotations to the in-vehicle network NT as a sensor value for calculating the speed (vehicle speed) of the vehicle 10. The driving assistance device 20 can calculate the speed, movement amount, etc. of the vehicle 10 based on the sensor value acquired from the vehicle speed sensor 183.

[0049] The monitor device 30 is provided on an instrument panel or the like in the passenger compartment of the vehicle 10 and includes a display unit 31 and an input unit 32 .

[0050] The display unit 31 is a display device such as a liquid crystal display (LCD) or an organic electroluminescent display (OLED). The display unit 31 displays, for example, an image based on image data transmitted by the driving assistance device 20, and an image for receiving an operation instruction to switch between a normal driving mode and a driving assistance mode when entering or leaving a parking lot.

[0051] The input unit 32 is, for example, a touch panel provided on the display screen of the display unit 31. The input unit 32 is configured to be transparent to the content displayed on the display screen of the display unit 31. This allows the input unit 32 to allow the occupant to visually recognize the display content of the display unit 31.

[0052] The input unit 32 receives instructions input by the driver or the like touching a position corresponding to the display content of the display unit 31, and transmits the instructions to the driving assistance device 20 via the in-vehicle network NT. Note that the input unit 32 is not limited to a touch panel, and may be a hard switch such as a push button.

[0053] 3 is a block diagram illustrating an example of a functional configuration of the driving assistance device 20 according to the embodiment. As illustrated in FIG. 3, the driving assistance device 20 includes a display control unit 201, an acquisition unit 204, a detection unit 205, and a route calculation unit 206 as functional units.

[0054] These functional units are realized, for example, by the above-mentioned CPU 21 reading and executing a program stored in a storage device such as the ROM 25. Alternatively, they are realized by the display control circuit 23 and the like operating under the control of the CPU 21 in accordance with the program.

[0055] Some or all of these functional units may be configured by hardware such as a circuit including an ASIC (Application Specific Integrated Circuit).

[0056] The display control unit 201 generates content to be displayed on the display unit 31 of the monitor device 30, and causes the content to be displayed on the display unit 31. That is, the display control unit 201 causes the display unit 31 to display, for example, a notification screen that a parking area in which the vehicle 10 can be parked has been detected, a selection screen for starting, pausing, or canceling driving assistance, an image of the surroundings of the vehicle 10 during driving assistance, and the like.

[0057] Furthermore, when the display unit 31 displays an image of the surroundings of the vehicle 10 during driving assistance, if the distance measuring unit 14 or the imaging unit 16 detects an obstacle or the like in the surroundings of the vehicle 10, the display control unit 201 performs processing to visually highlight the obstacle or the like in the image of the surroundings of the vehicle 10. Details of such processing will be described later.

[0058] The acquisition unit 204 acquires, as information about the surroundings of the vehicle 10, information about the transmission and reception of sound waves from the distance measurement unit 14 and captured images of the surroundings of the vehicle 10 from the imaging unit 16.

[0059] The detection unit 205 detects obstacles, parking spaces, parking areas, and the like around the vehicle 10 based on the surrounding information acquired by the acquisition unit 204.

[0060] Obstacles include various objects such as other vehicles, walls, pillars, fences, protrusions, steps, wheel chocks, etc. Obstacles may also be, for example, people walking in a parking lot.

[0061] A parking space is an area set up for parking the vehicle 10 and is defined by, for example, a partition line, a frame line, a straight line, a strip, a step, etc. A parking space is a parking space in which the vehicle 10 can be parked, that is, a parking space in which there are no obstacles, such as other vehicles, that would hinder the parking of the vehicle 10.

[0062] The detection unit 205 detects the presence or absence of an obstacle, the distance from the vehicle 10 to the obstacle, etc., based on, for example, the detection result of the distance measurement unit 14. In addition, the detection unit 205 detects the presence or absence of an obstacle, the parking space, their positions (orientations) relative to the vehicle 10, as well as their shapes, sizes, heights, etc., by, for example, image processing based on the image captured by the imaging unit 16.

[0063] By combining these detection results, the detection unit 205 extracts information such as whether there are any obstacles around the vehicle 10, the distance from the vehicle 10 to each obstacle if there are multiple obstacles, whether there are any parking spaces around the vehicle 10, whether it is possible to park the vehicle 10 in those parking spaces, i.e., whether they can be used as a parking area.

[0064] Based on the detection result by the detection unit 205, the route calculation unit 206 calculates a target position to which the vehicle 10 is to be guided, and calculates a travel route along which the vehicle 10 will move to the target position.

[0065] When parking (entering) the vehicle 10, the target position is the parking area detected by the detection unit 205. When exiting the vehicle 10 from a parking space, the target position is a predetermined location from which the vehicle 10 can safely start traveling, such as an aisle between multiple parking spaces.

[0066] In addition, the route calculation unit 206 may calculate a turning position as necessary. One or more turning positions are set when parking or leaving the parking lot is difficult after a single back or forward movement.

[0067] The route calculation unit 206 calculates a travel route of the vehicle 10 from the current position of the vehicle 10 to the target position so as to guide the vehicle 10 to the target position calculated as described above. If the travel route includes a turning point, the route calculation unit 206 calculates a travel route from the current position of the vehicle 10 to the target position via the turning point.

[0068] As described above, the route calculation unit 206 calculates movement routes for parking, such as reverse parking, forward parking, parallel parking by reversing, parallel parking by forwarding, etc. The route calculation unit 206 also calculates movement routes for leaving, such as forward leaving, backward leaving, parallel leaving by forwarding, parallel leaving by reversing, etc.

[0069] As described above, the driving assistance device 20 also functions as a periphery monitoring device that monitors the periphery of the vehicle 10 by detecting obstacles around the vehicle 10 during driving assistance. A driving assistance system 200 that adds components such as the distance measuring unit 14, the imaging unit 16, and the monitor device 30 to the driving assistance device 20 also functions as a periphery monitoring system.

[0070] (Example of operation of driving assistance device) Next, an example of the operation of the driving assistance device 20 according to the embodiment will be described with reference to Figures 4A to 4C. Figures 4A to 4C are schematic diagrams illustrating an example of a display on the monitor device 30 during parking assistance by the driving assistance device 20 according to the embodiment.

[0071] FIG. 4A shows an example of an image displayed on the display unit 31 of the monitor device 30 when the driver issues an instruction to start driving assistance via the input unit 32 of the monitor device 30 or the like.

[0072] As shown in FIG. 4A, when driving assistance is started, the display control unit 201 of the driving assistance device 20 causes the display unit 31 of the monitor device 30 to display, for example, a peripheral image 31F and an overhead image 31B.

[0073] The surrounding image 31F is a predetermined image selected from images captured by a plurality of imaging units 16 provided on the outer periphery of the vehicle 10. Specifically, the display control unit 201 selects, for example, an image captured in the traveling direction of the vehicle 10 from the images captured by the plurality of imaging units 16, and displays the image on the display unit 31.

[0074] The overhead image 31B is an image obtained by the display control unit 201 synthesizing images captured by a plurality of imaging units 16 provided on the outer periphery of the vehicle 10 into an overhead image looking down on the vehicle 10 from above. The display control unit 201 also displays a vehicle icon 10ic representing the vehicle 10 in the center of the overhead image 31B.

[0075] In the example of FIG. 4A, a rectangular mark 40 indicating the parking area detected based on the surrounding information from the imaging unit 16 is superimposed on each of the surrounding image 31F and the overhead image 31B.

[0076] 4A, in the peripheral image 31F, a mark 41 indicating the travel path of the vehicle 10 is displayed superimposed on the captured image from the imaging unit 16. The mark 41 includes, for example, a pair of lines that are approximately equal to the width of the vehicle 10 and extend in the traveling direction of the vehicle 10, such as in front of or behind the vehicle 10, and multiple horizontal lines that are drawn between the pair of lines at different distances from the vehicle 10.

[0077] In order to prevent the marks 40 and 41 from obscuring the image itself, the marks 40 and 41 are displayed semi-transparently, allowing the image behind them to be seen through the marks 40 and 41.

[0078] 4A, the peripheral image 31F and the overhead image 31B reflect a person OBa in the parking lot that is detected based on the peripheral information from the imaging unit 16. The person OBa is located on the movement path of the vehicle 10 and may become an obstacle to the vehicle 10 that is attempting to park in the parking area.

[0079] As described above, the detection unit 205 of the driving assistance device 20 detects a person OBa who may be an obstacle around the vehicle 10 undergoing driving assistance based on surrounding information from the distance measurement unit 14 and the imaging unit 16, and calculates the size, height, orientation relative to the vehicle 10, and distance from the vehicle 10 of the person OBa.

[0080] The display control unit 201 displays marks 50F and 50B in the peripheral image 31F and the overhead image 31B, respectively, superimposed on the image of person OBa, based on the detection result of the detection unit 205. These marks 50F and 50B are also displayed semi-transparently, allowing the image behind them to be seen through the marks 50F and 50B.

[0081] The display control unit 201 uses the same color for the marks 50F and 50B that are displayed superimposed on the image of the same person OBa. In the driving assistance device 20, in preparation for the case where multiple obstacles are detected, multiple colors of the marks 50F and 50B to be used for each obstacle are prepared.

[0082] The mark 50F as the first mark includes, for example, a pointer 51 and signals 52 and 53.

[0083] The pointer 51 as the first pointer is, for example, a circular mark and has a function of pointing to an obstacle. The pointer 51 is displayed at a position offset from the ground position of the obstacle detected by the detection unit 205, that is, for example, near the center position in the height direction of the obstacle. As in the example of FIG. 4A, when the obstacle is person OBa, the pointer 51 is displayed at, for example, the center position of the body length of person OBa, offset from the position of the feet of person OBa.

[0084] The signal 52 as the first signal is, for example, a cross mark placed within the circular pointer 51. When displaying the mark 50F on the peripheral image 31F, the display control unit 201 dynamically displays the signal 52 on the peripheral image 31F, for example, by changing the transparency of the signal 52 at a predetermined cycle.

[0085] In this case, in the mark 50F, which is originally displayed semi-transparently, the transparency of the signal 52 may be changed in two steps, or gradually through steps finer than two, from a transparency equal to or lower than the transparency of the pointer 51, whose transparency does not change, to a transparency above a predetermined value.

[0086] Furthermore, when the transparency of the signal 52 is periodically changed, there may be a time when the transparency of the signal 52 becomes 100%, that is, when the signal 52 disappears from the screen. In this case, the signal 52 should appear to blink on the peripheral image 31F.

[0087] The signal 53 as the second signal is, for example, a mark such as a plurality of line segments, dots, or polygons arranged at predetermined intervals around the periphery of the circular pointer 51. In the example of Fig. 4A, the signal 53 includes four triangular marks surrounding the pointer 51 from four directions. Each of these triangles surrounding the periphery of the pointer 51 is arranged so that one vertex faces the center of the pointer 51 and the side corresponding to the base relative to the vertex faces outward from the pointer 51.

[0088] When displaying the mark 50F on the peripheral image 31F, the display control unit 201 dynamically displays the signal 53 on the peripheral image 31F, for example by rotating the mark 50F around the pointer 51 at a predetermined speed. In the example of Fig. 4A, two pairs of triangular marks facing each other vertically and horizontally on either side of the pointer 51 are moved clockwise or counterclockwise. This allows the four triangular marks to be visually perceived as rotating around the pointer 51.

[0089] The mark 50B as the second mark includes at least a pointer 54, for example.

[0090] The second pointer 54 is, for example, a circular mark with four protrusions, and has the function of pointing to an obstacle. In this way, the pointer 54 preferably has a similar shape to the pointer 51 of the mark 50F that points to the same obstacle.

[0091] Furthermore, the pointer 54 is displayed near the ground position of the obstacle detected by the detection unit 205. If the obstacle is person OBa as in the example of Fig. 4A, the pointer 54 is displayed near the feet of person OBa, for example.

[0092] In addition, when an obstacle such as a person OBa is detected around the vehicle 10, the display control unit 201 may display marks 50F and 50B and also display a message such as "Please check the area around the vehicle directly" on the display unit 31.

[0093] FIG. 4B shows an example of an image displayed on the display unit 31 of the monitor device 30 after a predetermined time has elapsed since the state shown in FIG. 4A.

[0094] As shown in Figure 4B, for example, person OBa has not moved from the position in Figure 4A, and the display position of the pointer 51 of mark 50F in the peripheral image 31F and the display position of the pointer 54 of mark 50B in the overhead image 31B have not changed from the positions in Figure 4A.

[0095] When an obstacle such as person OBa is moving, the pointers 51 and 54 of the marks 50F and 50b move on the peripheral image 31F or the overhead image 31B so as to follow the obstacle accordingly.

[0096] Furthermore, after a predetermined time has passed since FIG. 4A, the transparency of signal 52 of mark 50F has increased in peripheral image 31F. That is, signal 52 is displayed lighter than in the state of FIG. 4A. Furthermore, the arrangement of the four triangular marks in signal 53 of mark 50F has changed. That is, the four triangular marks, which were arranged to approximately coincide with the vertices of the cross of signal 52 in FIG. 4A, have rotated around pointer 51, and are now respectively arranged at positions between the vertices of the cross of signal 52 in FIG. 4B.

[0097] While the person OBa is detected in the vicinity of the vehicle 10, the display control unit 201 continues to dynamically display the signals 52 and 53 of the mark 50F as described above at a predetermined cycle and a predetermined speed.

[0098] FIG. 4C shows an example of an image displayed on the display unit 31 of the monitor device 30 after a predetermined time has elapsed since the state shown in FIG. 4B.

[0099] As shown in FIG. 4C, for example, person OBa has not moved from the position in FIG. 4B, and marks 50F and 50B are still displayed superimposed on the image of person OBa in peripheral image 31F and overhead image 31B.

[0100] 4A, a new person OBb is reflected in the peripheral image 31F and the overhead image 31B, which are detected based on peripheral information from the imaging unit 16. The person OBb is located on the path of movement of the vehicle 10, closer to the vehicle 10 than the person OBa, and may become an obstacle to the vehicle 10 attempting to park in the parking area.

[0101] The detection unit 205 detects the new person OBb as an obstacle based on surrounding information from the distance measurement unit 14 and the imaging unit 16, and calculates the size, height, direction relative to the vehicle 10, distance from the vehicle 10, etc. of this person OBb.

[0102] Furthermore, as described above, when multiple obstacles such as persons OBa and OBB are detected, the detection unit 205 calculates the order of the distances of these obstacles from the vehicle 10. In the example of Fig. 4C, the detection unit 205 calculates that of the two obstacles, persons OBa and OBB, person OBB is the obstacle closest to the vehicle 10, and calculates person OBa to be the obstacle next closest to the vehicle 10 after person OBB.

[0103] Based on the detection result of the detection unit 205, the display control unit 201 switches the display of the marks 50F, 50B that were displayed superimposed on the image of the person OBa in the peripheral image 31F and the overhead image 31B to a mode corresponding to the obstacle that is second closest to the vehicle 10.

[0104] As described above, the driving assistance device 20 is configured to display the marks 50F, 60F... and the marks 50B, 60B... in different colors for a plurality of obstacles. These colors are assigned according to the distance from the vehicle 10 to the obstacles, for example.

[0105] At this time, for example, the most visible color such as red may be assigned to the obstacle closest to the vehicle 10, followed by increasingly more subdued colors such as orange and then yellow. Also, when only one obstacle is detected, as in the examples of Figures 4A and 4B described above, the color assigned to the obstacle closest to the vehicle 10 may be used for that obstacle.

[0106] In the example of Fig. 4C, the display control unit 201 changes the color of the marks 50F and 50B attached to the image of the person OBa from the color assigned to the obstacle closest to the vehicle 10 to the color assigned to the obstacle second closest to the vehicle 10. In this case as well, the marks 50F and 50B are displayed in the same color.

[0107] Furthermore, the display control unit 201 stops the change in the transparency of the signal 52 in the mark 50F and switches the display mode of the signal 52 to a static display. Furthermore, the display control unit 201 stops the rotation of the signal 53 in the mark 50F and switches the display mode of the signal 53 to a static display.

[0108] The display control unit 201 also displays marks 60F and 60B in the peripheral image 31F and the overhead image 31B, superimposed on the image of the newly detected person OBb, based on the detection results and determination results of the detection unit 205. These marks 60F and 60B are also displayed semi-transparently in the same color. At this time, the marks 60F and 60B are given the color assigned to the obstacle closest to the vehicle 10, which was assigned to marks 50F and 50B in FIGS. 4A and 4B, instead of mark 50F.

[0109] The mark 60F as the first mark includes, for example, a pointer 61 and signals 62 and 63, and is displayed in place of the mark 50F superimposed on the image of the person OBb in the same manner as the mark 50F in FIGS. 4A and 4B.

[0110] The pointer 61 as a first pointer is displayed, for example, near the center position of the body length of the person OBb, offset from the position of the feet of the person OBb, and points to the person OBb. When an obstacle such as the person OBb is moving, the pointer 61 moves on the peripheral image 31F so as to follow the obstacle accordingly.

[0111] The signal 62 as the first signal is arranged, for example, within a circular pointer 61, and the transparency thereof changes at a predetermined cycle.

[0112] The signal 63 as the second signal is arranged, for example, so as to surround the periphery of the circular pointer 61 at a predetermined interval, and rotates around the pointer 51 at a predetermined speed.

[0113] The mark 60B as the second mark includes, for example, at least a pointer 64, and is displayed superimposed on the image of the person OBb in place of the mark 50B in the same manner as the mark 50B in FIGS. 4A and 4B.

[0114] A pointer 64 as a second pointer is displayed, for example, near the feet of the person OBb, and points to the person OBb.

[0115] As described above, while driving assistance is being performed, display control unit 201 continues to display peripheral image 31F and overhead image 31B based on the captured image captured by imaging device 16 on display unit 31. Furthermore, based on the detection result of detection unit 205, display control unit 201 displays marks 50F, 60F... and marks 50B, 60B... superimposed on an image of an obstacle such as a person detected around vehicle 10.

[0116] (Example of processing by a driving assistance device) Next, an example of driving assistance processing by the driving assistance device 20 of the embodiment will be described with reference to Fig. 5. Fig. 5 is a flow chart showing an example of the procedure of the driving assistance processing by the driving assistance device 20 according to the embodiment. Note that the surroundings monitoring processing by the driving assistance device 20 is performed in parallel with the driving assistance processing.

[0117] As shown in FIG. 5, the driving assistance device 20 waits for an input from the driver of the vehicle 10 or the like to instruct the start of driving assistance (step S101: No).

[0118] When a command to start driving assistance is input from the driver or the like (step S101: Yes), the detection unit 205 starts detecting parking areas, etc. around the vehicle 10 that are the target position for driving assistance, and detecting obstacles, such as people, around the vehicle 10, based on surrounding information from the distance measurement unit 14 and the imaging unit 16 (step S102).

[0119] The detection unit 205 continues to detect the situation around the vehicle 10 until the vehicle 10 reaches the target position and the driving assistance ends.

[0120] Based on the detection result of the detection unit 205, the route calculation unit 206 calculates a target position to which the vehicle 10 is to be guided, a turning position if necessary, and a travel route (step S103).

[0121] The display control unit 201 displays, on the display unit 31 of the monitor device 30, an image of the area ahead in the traveling direction of the vehicle 10, among the images captured by the multiple image capturing devices 16, as a surrounding image 31F of the vehicle 10. The display control unit 201 also combines the images captured by the multiple image capturing devices 16, and displays an overhead image 31B with a vehicle icon 10ic added to it, on the display unit 31 of the monitor device 30 (step S104).

[0122] At this time, the display control unit 201 displays a mark 40 indicating the target position of the parking area or the like calculated by the path calculation unit 206 superimposed on the peripheral image 31F and the overhead image 31B, and also displays a mark 41 indicating the movement path of the vehicle 10 superimposed on the peripheral image 31F.

[0123] The detection unit 205 determines whether or not there is an obstacle around the vehicle 10 (step S105). If there is no obstacle around the vehicle 10 (step S105: No), the processes of steps S106 to S111 are skipped.

[0124] If there is an obstacle around the vehicle 10 (step S105: Yes), the detection unit 205 determines whether there are multiple obstacles around the vehicle 10 (step S106).

[0125] If there is only one obstacle around the vehicle 10 (step S106: No), the display control unit 201 periodically changes the transparency of the symbol 52 of the mark 50F to be displayed in the surrounding image 31F, and performs dynamic processing such as rotating the symbol 53 around the pointer 51 (step S109).

[0126] The display control unit 201 displays a mark 50F, which is obtained by performing dynamic processing on symbols 52 and 53, superimposed on the image of the obstacle in the peripheral image 31F, near the center position in the height direction offset from the ground position of the obstacle. The display control unit 201 also displays a mark 50B of the same color as mark 50F superimposed on the image of the obstacle in the overhead image 31B, at the ground position of the obstacle (step S110).

[0127] If there are multiple obstacles around the vehicle 10 (step S106: Yes), the detection unit 205 calculates the order of the shortest distances from the vehicle 10 for each of the obstacles (step S107).

[0128] Based on the detection result of the detection unit 205, the display control unit 201 selects the color assigned to the nearest obstacle as the display color of the mark 60F for the obstacle closest to the vehicle, and performs dynamic processing on the signals 62, 63 on the mark 60F (step S108).

[0129] The display control unit 201 displays a mark 60F, which is obtained by performing dynamic processing on symbols 62 and 63, superimposed on the image of the obstacle in the peripheral image 31F, near the center position in the height direction offset from the ground position of the obstacle. The display control unit 201 also displays a mark 60B of the same color as mark 60F superimposed on the image of the obstacle in the overhead image 31B, at the ground position of the obstacle (step S110).

[0130] The display control unit 201 determines whether the displayed obstacle is the last obstacle among the detected obstacles (step S111).

[0131] If there are any unprocessed obstacles remaining (step S111: No), the display control unit 201 repeats the process of step S110 for the number of obstacles. However, except for the nearest obstacle, the display control unit 201 displays the marks 50F and 50B without performing dynamic processing on the symbols 52 and 53.

[0132] After displaying all obstacles as described above (step S111: Yes), the driving assistance device 20 determines whether the driving assistance has ended, for example, when the vehicle 10 reaches a target position (step S112).

[0133] The driving assistance device 20 repeats the processes of steps S105 to S111 until the driving assistance ends (step S112: No), and ends the surroundings monitoring process when the driving assistance ends (step S112).

[0134] This completes the driving assistance process by the driving assistance device 20 of the embodiment.

[0135] (Overview) The driving assistance device assists the driver in driving the vehicle into and out of a parking lot, etc., based on information about the vehicle's surroundings from various sensors such as a distance measurement unit and an image capture unit. During driving assistance, the driving assistance device monitors the vehicle's surroundings, and if it detects an obstacle or the like, it displays a highly visible colored mark on a monitor device or the like to alert the driver.

[0136] According to the technology of the above-mentioned Patent Document 1, passengers on a train platform are detected, and a color-coded frame is attached to each passenger according to the risk level of the passenger's behavior, and risky behavior on the platform is monitored. According to the technology of the above-mentioned Patent Document 2, in a vehicle traveling normally on the road, pedestrians with a short time to collision calculated based on the pedestrian's walking speed are marked and displayed on the driver's head-up display.

[0137] According to the technology of Patent Document 3 mentioned above, road facilities are efficiently monitored by displaying warnings according to the content of the warning, such as fires on expressways, trespassing people, etc. According to the technology of Patent Document 4 mentioned above, in order to monitor the area around an excavator working in a depression in the ground, the color and brightness of the object is changed according to the distance from the excavator, improving visibility around the excavator.

[0138] According to the technology of Patent Document 5, when a vehicle is traveling normally on a road, the level of the risk potential is displayed on the driver's head-up display by rotating multiple arc-shaped indicator images surrounding the vehicle ahead and expanding or contracting a linear gauge image.

[0139] However, there is a possibility that simply changing the display color as in Patent Documents 1 and 2 may not be enough to draw the driver's attention. For example, if the driver is elderly, it may be difficult for the driver to distinguish colors due to aging of color vision, which further increases the risk of the driver overlooking the display informing the driver of the detection of an obstacle.

[0140] Furthermore, when monitoring the surrounding area during driving assistance to assist the driver in entering or leaving a parking lot, unlike when the information is displayed on the driver's head-up display during normal driving, as in Patent Documents 2 and 5, it may be difficult for the driver to pay attention to the display on a monitor device located on the vehicle's instrument panel or the like while performing complicated driving operations.

[0141] In such a situation, simply changing the display color or simply rotating the mark itself as in Patent Document 5 may not be enough to draw attention.

[0142] According to the driving assistance device 20 of the embodiment, the display control unit 201 displays a pointer 51 that indicates an obstacle, a signal 52 that is placed within the pointer 51 and is dynamically displayed so that its transparency changes periodically, and a signal 53 that is placed around the pointer 51 and is dynamically displayed so that it rotates around the pointer 51.

[0143] In this way, the signals 52 and 53 are dynamically displayed in different modes, namely, by periodically changing the transparency and by rotating. Furthermore, the signals 52 and 53 are dynamically displayed inside and outside the pointer 51, respectively.

[0144] Therefore, even if a driver, such as an elderly driver, easily misses changes in the transparency of signal 52, he or she may easily notice the rotation of the other signal 53, and signals 52 and 53 complement each other to prevent the driver from overlooking the change.

[0145] With this configuration, the attention-attracting power of the mark 50F attached to the obstacle is significantly improved, and the driver's attention to the obstacle can be more reliably drawn even during driving assistance. Also, for example, even when the obstacle is stationary, the driver's attention to the obstacle can be more reliably drawn.

[0146] According to the driving assistance device 20 of the embodiment, the display control unit 201 displays the mark 50F superimposed on the obstacle in the peripheral image 31F, thereby making it easier to grasp the position of the obstacle relative to the vehicle 10 in the peripheral image 31F.

[0147] According to the driving assistance device 20 of the embodiment, the display control unit 201 displays the mark 50B superimposed on the ground position of the obstacle in the overhead-view image 31B. The overhead-view image 31B is a composite image of a plurality of captured images, and in the overhead-view image 31B, three-dimensional obstacles such as people OBa and OBB are displayed stretched in the height direction. With the above configuration, the position of the obstacle relative to the vehicle 10 can be easily grasped even in the overhead-view image 31B.

[0148] According to the driving assistance device 20 of the embodiment, the mark 50B includes a pointer 54 of the same color as the pointer 51. In this way, by using the marks 50F and 50B of the same color for the same obstacle, it is possible to easily determine whether the obstacles displayed in the peripheral image 31F and the overhead image 31B are the same or different.

[0149] According to the embodiment of the driving assistance device 20, the display control unit 201 displays the mark 60F in a predetermined color for the obstacle closest to the vehicle 10 in the surrounding image 31F, and dynamically displays the signals 62, 63 of the mark 60F, and for other obstacles, displays the marks 50F... in a color different from the color of the mark 60F, which is a different color for each obstacle, and statically displays the signals 52... without changing the transparency, and statically displays the signals 53... without rotating them.

[0150] This makes the mark 60F attached to the obstacle that is closest to the vehicle 10 and likely to hinder the movement of the vehicle 10 stand out more than the other marks 50F, thereby further attracting the driver's attention. In addition, by dynamically displaying the mark 60F, it is possible to easily identify the obstacle that is closest to the vehicle 10 among multiple obstacles.

[0151] In the above embodiment, for example, the marks 50F and 60F have the same size, and the marks 50B and 60B have the same size. However, the marks 50F, 60F... and the marks 50B, 60B... attached to multiple obstacles may have different sizes. In this case, the marks closer to the vehicle 10 may be displayed larger.

[0152] In the above-described embodiment, for example, the marks 50F and 60F have the same shape, and the marks 50B and 60B have the same shape. However, the marks 50F, 60F... and the marks 50B, 60B... attached to the plurality of obstacles may have various different shapes.

[0153] Even in this case, it is preferable that marks 50F, 50B, marks 60F, 60B, etc., indicating the same obstacle in peripheral image 31F and overhead image 31B have similar shapes, which makes it easier to associate the same obstacles displayed in peripheral image 31F and overhead image 31B.

[0154] In the above embodiment, when the driving assistance device 20 detects an obstacle around the vehicle 10, it puts a mark on the monitor device 30 to warn the driver. However, the driving assistance device 20 may have a function to control the vehicle 10 to avoid contact with the detected obstacle in addition to warning the driver.

[0155] In this case, for example, the driving assistance device 20 may be configured to be able to control the braking system 140, and the braking system 140 may apply the brakes to the vehicle 10 to avoid contact with the obstacle.

[0156] In the above-described embodiment, the driving assistance device 20 provides driving assistance by, for example, showing the route of the vehicle 10 to the driver who drives the vehicle 10. However, the driving assistance device 20 may have a function of providing driving assistance by controlling part or all of the driving operation on behalf of the driver.

[0157] In this case, for example, the driving assistance device 20 may be configured to be able to control the steering system 160, and the steering system 160 may control the direction of movement of the vehicle 10. Alternatively, the driving assistance device 20 may be configured to be able to control the braking system 140, the acceleration system 150, and the like in addition to the steering system 160, and may provide driving assistance through automatic driving.

[0158] However, in either of the above cases, the driving assistance device 20 is configured to allow the driver to operate the vehicle 10 himself / herself to avoid contact with the obstacle if the driver deems it necessary after visually confirming the obstacle, for example. [Explanation of symbols]

[0159] 10...Vehicle 14...Distance measurement section 16...imaging unit 20...Driving assistance device 206...Route calculation unit 30...Monitoring device 31...Display section 31B...Bird's-eye view 31F... Peripheral images 32...Input section 50B, 50F, 60B, 60F...Mark 51, 54, 61, 64...pointers 52, 53, 62, 63... Signal 201...Display control unit 204…Acquisition Department 205...Detection unit

Claims

1. A surroundings monitoring device that monitors the surroundings of a vehicle having a sensor that collects surrounding information, a detection unit that, when a user of the vehicle issues an instruction to start driving assistance that assists in parking or leaving the vehicle, detects obstacles around the vehicle based on the surrounding information from the sensor, and, when there are multiple obstacles, calculates an order of the obstacles in terms of their proximity to the vehicle; and a display control unit that displays a peripheral image of the vehicle including the obstacle and an overhead image on a display device within the vehicle, The display control unit a first pointer pointing to the obstacle; a first signal disposed within the first pointer; a second signal arranged around the first pointer; and a first mark including the first signal superimposed on the obstacle in the peripheral image; a second mark including a second pointer of the same color as the first pointer is displayed superimposed on the ground contact position of the obstacle in the overhead image; In the surrounding image, for the obstacle closest to the vehicle, the first mark is displayed in a first color, and the first signal is dynamically displayed so that the transparency of the first signal changes periodically, and the second signal is dynamically displayed so that the second signal rotates around the first pointer; In the peripheral image, for the obstacles other than the obstacle closest to the vehicle, the first mark is displayed in a color different from the first color, the color being different for each obstacle, and the first signal is displayed statically without changing its transparency, and the second signal is displayed statically without rotating. Perimeter monitoring device.

2. The display device is provided on an instrument panel of the vehicle. The periphery monitoring device according to claim 1 .

3. The peripheral image is an image of a region ahead in the traveling direction of the vehicle. The surroundings monitoring device according to claim 1 or 2.

4. A surroundings monitoring method for monitoring the surroundings of a vehicle having a sensor for collecting surrounding information, comprising: when a command to start driving assistance for assisting parking or leaving the vehicle is received from a user of the vehicle, detecting obstacles around the vehicle based on the surrounding information from the sensor, and when there are multiple obstacles, calculating an order of closest distance from the vehicle for each of the obstacles; a surrounding image of the vehicle including the obstacle and an overhead image are displayed on a display device inside the vehicle; The display device includes: a first pointer pointing to the obstacle; a first signal disposed within the first pointer; a second signal arranged around the first pointer; and a first mark including the first signal superimposed on the obstacle in the peripheral image; a second mark including a second pointer of the same color as the first pointer is displayed superimposed on the ground contact position of the obstacle in the overhead image; In the surrounding image, for the obstacle closest to the vehicle, the first mark is displayed in a first color, and the first signal is dynamically displayed so that the transparency of the first signal changes periodically, and the second signal is dynamically displayed so that the second signal rotates around the first pointer; In the peripheral image, for the obstacles other than the obstacle closest to the vehicle, the first mark is displayed in a color different from the first color, the color being different for each obstacle, and the first signal is displayed statically without changing its transparency, and the second signal is displayed statically without rotating. Perimeter surveillance methods.

Images