JP2008298532A - Obstruction measurement method, device, and system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an obstruction measurement method, an obstruction measurement device, and an obstruction measurement system by which a calculation amount per unit time becomes constant no matter whether speed is high or low, the upper limit of the calculation amount per unit time is prescribed, and cost reduction is achieved in either of hard processing and soft processing. <P>SOLUTION: In this obstruction measurement method, an object area of obstruction measurement and the resolution or the frame rate of an image by a stereo camera are changed according to the speed of a traveling object, when the distance from the traveling object up to an obstruction is measured with the stereo camera. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an obstacle measurement method, an obstacle measurement device, and an obstacle measurement system for measuring a distance to an obstacle.

  Patent Document 1 discloses a stereo monitoring apparatus and method using a stereo camera having a plurality of output modes, calculates distance data from an image from a stereo camera having two output modes (interlaced, non-interlaced), and The load of image processing is suppressed by switching the output mode according to the distance of the object or the speed of the host vehicle. Since processing is performed with “non-interlace + upper screen” during high-speed traveling and “interlace + full screen” during low-speed traveling, the amount of information in one frame is the same. As two output modes, there is a method of selecting an arbitrary line by changing the vertical angle of view.

Patent document 2 discloses an image processing apparatus for a vehicle that detects obstacles around the vehicle and a shape of a running path based on image information, and an image from one high-speed camera is displayed as a high frame from a running state of the vehicle (vehicle speed or the like). By dividing into an area to be extracted at a rate and an area to be extracted at a low frame rate, an image with a high frame rate can be handled without degrading the image quality. Alternatively, a region is selected from two images of a high speed camera and a low speed camera.
JP 2003-304528 A JP 2003-259361 A

  The apparatus / method of Patent Document 1 does not have a plurality of resolutions in the screen, and does not change the horizontal angle of view, and the frame rate is constant, so the amount of calculation for distance calculation changes. The device of Patent Document 2 has images with different frame rates in the same screen, and is not a stereo camera configuration, and does not obtain distance information of an object.

  Generally, when a vehicle travels at a high speed, it travels on a road with a large radius of curvature, such as an expressway, so there are few obstacles to watch out at the edge of the angle of view, but when traveling at a low speed, it travels mainly on a general road. It is necessary to pay attention to the edge of the angle of view because cars are expected to jump out at intersections and pedestrians jump out.

  In view of the above-mentioned problems of the prior art, the present invention has a constant amount of calculation per unit time regardless of whether the speed is high or low, defines an upper limit of the amount of calculation per unit time, and performs hardware processing / software processing. It is an object of the present invention to provide an obstacle measurement method, an obstacle measurement device, and an obstacle measurement system that can achieve cost reduction.

  In order to achieve the above object, a first obstacle measurement method according to the present invention is an obstacle measurement method for measuring a distance from a running object to an obstacle with a stereo camera, the obstacle measurement target region and The frame rate of the image by the stereo camera is changed according to the speed of the traveling object.

  According to this obstacle measurement method, the amount of calculation per unit time can be reduced regardless of whether the speed is low or high, by changing the target area for obstacle measurement according to the speed of the traveling object and the frame rate of the image by the stereo camera. The upper limit of the calculation amount per unit time is specified, and cost reduction can be achieved regardless of whether the distance measurement (parallax calculation) calculation process is a hardware process or a software process.

  In the above obstacle measurement method, when the traveling object is relatively fast, by limiting the target area to a part of the screen, even if the frame rate is increased, the amount of calculation per unit time is relatively slow. In some cases, the target area can be made substantially the same as the entire area of the screen, and can be made constant in the same manner as when the frame rate is reduced, and the upper limit of the calculation amount per unit time can be defined.

  Further, even when the traveling object is relatively slow, even if the target area is almost the entire screen, the amount of calculation per unit time is made equal to that of the relatively high speed described above by reducing the frame rate. In addition to being constant, it is possible to define the upper limit of the calculation amount per unit time.

  When traveling at high speeds, the road is often passed along a road with a large radius of curvature, such as an expressway, and the screen is used to avoid a rear-end collision with the preceding vehicle, as described above, rather than setting the measurement target area at the angle of view. It is important to set a measurement target area at the center or at the top, and it is necessary to measure an obstacle at a high frame rate because it takes a short time from the detection to the avoidance action. On the other hand, when driving at low speeds, it often runs on roads and intersections with a small radius of curvature, such as general roads. Since it is necessary to pay, it is important to set the measurement target region over the entire area as described above. Compared to high-speed driving during low-speed driving, there is no problem even if obstacles are measured at a low frame rate because there is a time lapse between detection and transition to avoidance behavior.

  A second obstacle measuring method according to the present invention is an obstacle measuring method for measuring a distance from a traveling object to an obstacle with a stereo camera, wherein the obstacle measurement target region and the resolution of the image by the stereo camera are determined. The speed is varied according to the speed of the traveling object.

  According to this obstacle measurement method, the amount of calculation per unit time is constant regardless of whether it is high speed or low speed by changing the resolution of the target area where the obstacle is measured and the stereo camera image according to the speed of the traveling object. Thus, the upper limit of the amount of calculation per unit time is defined, and cost reduction can be achieved regardless of whether the distance measurement (parallax calculation) calculation process is a hardware process or a software process.

  In the above obstacle measurement method, when the traveling object is relatively high speed, by limiting the target area to a part of the screen, even when the resolution is increased, the calculation amount per unit time is relatively low In addition, it is possible to make the target area almost the whole area of the screen and to make it constant, which is the same as when the resolution is reduced, and to define the upper limit of the calculation amount per unit time.

  Further, even when the traveling object is relatively slow, even if the target area is almost the entire screen, the amount of calculation per unit time is kept constant by making the resolution small, equivalent to the case of the relatively high speed described above. And the upper limit of the calculation amount per unit time can be defined.

  As described above, when the vehicle is traveling at a high speed, the target region of the three-dimensional measurement is limited to the central portion and executed with high resolution. When traveling at low speed, the target area of the three-dimensional measurement is set to the entire screen and executed at a low resolution. The limit distance that can be shifted to the avoidance action at the time of low-speed driving is closer than that at the time of high-speed driving, and thus the area occupied by the obstacle on the screen is large, and can be detected even at a low resolution. On the other hand, when driving at high speed, the limit distance that can be shifted to the avoidance action is relatively long, so the area occupied by the obstacle on the screen is reduced. For this reason, in order to detect reliably, it is necessary to make it high resolution.

  In each of the above obstacle measurement methods, the calculation of the distance in the distance measurement is performed by using the POC method (phase-only correlation method), thereby enabling highly accurate measurement.

  In each of the above obstacle measurement methods, when the target area is changed based on the speed, for example, when driving at a low speed, the left and right end areas are changed to the target area, so that the vehicle or the walk by jumping out at the angle of view end. The person can be measured and monitored with priority, and the distance of the obstacle can be measured only at the upper part of the angle of view by changing the upper area to the target area when traveling at high speed.

  In addition, by changing the target area based on the speed and the distance to the obstacle, the target area is dynamically set based on distance information and speed, so that it can be appropriately adapted to changes in road conditions, vehicle flow, etc. Yes. In this case, it is preferable that the target area is set to a long distance when traveling at a high speed and is set to a short distance when traveling at a low speed.

  In this case, it is preferable that the distance to the obstacle when the target area is changed is performed using a SAD (sum of absolute differences) method.

  A first obstacle measuring device according to the present invention is an obstacle measuring device that measures a distance from a running object to an obstacle with a stereo camera, and the obstacle measurement target region is based on the speed of the running object. Means for changing, and means for changing a frame rate of an image by the stereo camera based on the speed.

  According to this obstacle measuring device, the amount of calculation per unit time can be reduced regardless of whether the speed is low or high, by changing the target area for obstacle measurement according to the speed of the traveling object and the frame rate of the image by the stereo camera. The upper limit of the calculation amount per unit time is specified, and cost reduction can be achieved regardless of whether the distance measurement (parallax calculation) calculation process is a hardware process or a software process.

  A second obstacle measuring device according to the present invention is an obstacle measuring device that measures a distance from a running object to an obstacle using a stereo camera, and the obstacle measurement target region is based on the speed of the running object. Means for changing, and means for changing the resolution of an image obtained by the stereo camera based on the speed.

  According to this obstacle measurement device, the amount of calculation per unit time is constant regardless of whether it is high speed or low speed by changing the resolution of the image by the target area and the stereo camera that performs obstacle measurement according to the speed of the traveling object. Thus, the upper limit of the amount of calculation per unit time is defined, and cost reduction can be achieved regardless of whether the distance measurement (parallax calculation) calculation process is a hardware process or a software process.

  Each of the obstacle measurement devices can be configured to execute the obstacle measurement method described above. In addition, each said obstacle measuring device can be made to measure distance by being mounted in a traveling object.

  An obstacle measurement system according to the present invention includes the above-described obstacle measurement device, a determination unit that determines a risk related to the obstacle based on the measured distance information, and a warning that issues a warning when the risk is determined. And a section.

  According to this obstacle measurement system, attention can be paid to the danger by the warning from the warning section, the danger avoidance operation can be performed, and the cost of the obstacle measurement system can be reduced.

  According to the obstacle measurement method, obstacle measurement device, and obstacle measurement system of the present invention, the amount of calculation per unit time is constant regardless of whether the speed is high or low, and the upper limit of the amount of calculation per unit time is specified. The cost can be reduced regardless of whether the distance measurement (parallax calculation) calculation process is a hardware process or a software process.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  <First Embodiment>

  FIG. 1 is a block diagram schematically showing an obstacle measuring apparatus for a vehicle according to a first embodiment. As shown in FIG. 1, the obstacle measurement device 10 for a vehicle includes a right camera 11, a left camera 12, an image correction unit 13 that corrects image information from the cameras 11 and 12, and images by the cameras 11 and 12. An image processing unit 14 that performs image processing on a camera image from the information, a distance data calculation unit 15 that calculates distance data between the obstacles from the image information in the three-dimensional measurement region, and a vehicle speed that detects the speed of the vehicle Sensor 16 and is mounted on a vehicle.

  Each of the right camera 11 and the left camera 12 includes an optical system such as a lens and an image pickup device including a CCD, a CMOS image sensor, and the like. The right camera 11 and the left camera 12 are arranged at a predetermined interval in the front of the vehicle to form a stereo camera. Image information of obstacles such as existing pedestrians and preceding vehicles is obtained as an electrical signal.

  The image correction unit 13 corrects distortion or the like generated in the periphery of the lenses of the cameras 11 and 12 with respect to the image information from the cameras 11 and 12.

  The image processing unit 14 performs image processing on the corrected image information, and the region selection unit 14a of the image processing unit 14 sets the three-dimensional measurement region for measuring the distance to the obstacle in the image to the vehicle speed detected by the vehicle speed sensor 16. Select based on.

  Further, the image processing unit 14 changes the frame rate of the image (the number of times the image is processed and rewritten per unit time) based on the vehicle speed detected by the vehicle speed sensor 16. In addition, what is mounted in the vehicle can be used for the vehicle speed sensor 16.

  The distance data calculation unit 15 displays the right image obtained from the right camera 11 and the left image obtained from the left camera 12 on the same obstacle on the screen in the horizontal direction. The distance to the obstacle can be calculated three-dimensionally based on the horizontal position deviation (parallax). That is, since the parallax and the distance are in an inversely proportional relationship, the distance can be measured by measuring the parallax. The distance data calculation unit 15 performs such calculation of distance data within a three-dimensional measurement region selected based on the vehicle speed.

  Specifically, the distance data calculation unit 15 uses a correlation method based on a sum of absolute differences (SAD) or a phase-only correlation (POC) as a method of the above-described parallax calculation. be able to.

  The SAD method is a commonly used parallax measurement method. For example, a paper by Motoki Arai, Kazuhiko Sumi, and Takashi Matsuyama “Optimization of correlation function and sub-pixel estimation method in image block matching” ( Information Processing Society of Japan Research Report CVIM-144-5, pp.33-40, May 2004) and Japanese Patent Application Laid-Open No. 2000-283753 can be referred to.

  The POC method (phase-only correlation method) uses phase information obtained by performing Fourier transform on an image signal converted into a digital signal to obtain a phase signal and an amplitude signal, and performing inverse Fourier transform on only the phase signal. Since this is a dimension measurement method and uses only phase components, highly accurate matching is possible, and the accuracy of distance measurement is higher than that of the SAD method. The POC method is, for example, a paper by Yasuhiro Fukuda, Masahide Abe, and Masayuki Kawamata "Realization of video image misregistration using phase-only correlation by DSP" ) You can refer to document number 215-3).

  The distance data calculation unit 15 can process the calculation for the distance calculation by the SAD method and the POC method by hardware using an integrated element or the like, but it may be processed by a CPU (Central Processing Unit) as software. Good. In this case, the CPU executes a predetermined calculation according to a predetermined program.

  FIG. 2 is a schematic diagram showing three-dimensional measurement areas A, B, and C that can be selected by the area selection unit 14a of FIG.

  The region selection unit 14a in FIG. 1 can select a three-dimensional measurement region for performing three-dimensional measurement from the plurality of regions A, B, and C shown in FIG. 2, for example, vehicle speed s2> vehicle speed s1 (FIG. 3B). If the vehicle speed detected by the vehicle speed sensor 16 is a high speed equal to or higher than s2, the narrowest area A is selected. If the vehicle speed is equal to or lower than s2 and the medium speed is equal to or higher than s1, an intermediate area B is selected. When the speed is low, the widest area C is selected.

  Next, control of the selection of the three-dimensional measurement region and the change of the frame rate based on the vehicle speed in the image processing unit 14 and the region selection unit 14a of FIG. 1 will be described with reference to FIGS.

  FIG. 3 shows the time T of the frame (a), the vehicle speed (b), the actual frame rate (≈image processing time) (c), and the three-dimensional measurement region (d) in the control by the obstacle measuring device 10 of FIG. It is a figure which shows typically the relationship. FIG. 4 is a schematic diagram showing a camera image and a three-dimensional measurement region by the obstacle measuring device of FIG. 1, and shows a case of low speed running (a) and a case of high speed running (b).

  When the vehicle equipped with the obstacle measuring device 10 in FIG. 1 starts at time T0 in FIG. 3, the vehicle travels at time T0 to T1 at low speed (s1 or less) as shown in FIG. As shown in (d), the largest area C in FIG. 2 is selected as the three-dimensional measurement area, and the frame in FIG. 3 (a) is reduced in the actual frame rate (image processing time is reduced as shown in FIG. 3 (c)). (Long) change and image processing.

  For example, as shown in FIG. 4A, when a vehicle equipped with the obstacle measuring apparatus 10 of FIG. 1 travels on the road 1 at a low speed (vehicle speed <s1), the selected maximum three-dimensional measurement region C is displayed on the screen 9. In the region C, the image of the preceding vehicle 2 ahead of the vehicle is processed at a small actual frame rate (relatively long image processing time). In this way, during low-speed running, the three-dimensional measurement area is set to almost the entire screen 9 and is executed at a relatively small frame rate.

  Next, when the vehicle speed increases to a medium speed (s2 or less, s1 or more), the intermediate region B in FIG. 2 is set to 3 in the middle speed period of time T2 to T3 in FIG. 3 as shown in FIG. While selecting as a dimension measurement region, the frame of FIG. 3A is subjected to image processing by changing the actual frame rate to medium (image processing time is medium) as shown in FIG. 3C.

  Next, when the vehicle speed further increases to a high speed (s2 or more), the smallest area A in FIG. 2 is used as a three-dimensional measurement area in the high speed period from time T4 to T5 in FIG. 3 as shown in FIG. At the same time, the frame shown in FIG. 3A is subjected to image processing by changing the actual frame rate to a larger value (shortening the image processing time) as shown in FIG. 3C.

  For example, when a vehicle equipped with the obstacle measuring device 10 of FIG. 1 travels on the road 1 at high speed (vehicle speed> s2), the selected minimum three-dimensional measurement region A is almost at the center (or upper part) of the screen 9. In the region A, the image of the preceding vehicle 2 ahead of the vehicle is processed at a large actual frame rate (relatively short processing time).

  As described above, when the vehicle is traveling at a high speed, the three-dimensional measurement region is limited to the central portion (or upper portion) of the screen 9 and executed at a relatively large frame rate. Even if it is limited to such a small area A, there is no problem because the road linearity and parallelism are maintained during high speed traveling. On the contrary, when the road shape is extremely meandering up and down and left and right, there is no problem because extreme high-speed traveling is not performed.

  The steps (S01 to S08) of measuring the distance between the vehicle and the obstacle by the above-described obstacle measuring device 10 will be described with reference to the flowchart of FIG.

  When obstacle measurement is started in a vehicle equipped with the obstacle measurement apparatus 10 of FIG. 1, first, left and right images are input to the image correction unit 13 from the right camera 11 and the left camera 12 (S01), and the image is converted into an image correction unit. 13 is corrected (S02).

  Then, when the vehicle speed detected by the vehicle speed sensor 16 is a high speed equal to or higher than s2 (S03), the area selection unit 14a selects the minimum area A in FIG. 2 as a three-dimensional measurement area (S05). If the vehicle speed is s2 or less and a medium speed of s1 or more (S04), the intermediate area B in FIG. 2 is selected as the three-dimensional measurement area (S06), and if the vehicle speed is s1 or less (S04), The two largest areas C are selected as the three-dimensional measurement area (S07). When region A is selected, the frame rate is high, when region C is selected, the frame rate is low, and when region B is selected, the frame rate is set to the middle.

  Next, an image is processed at each frame rate in the region A, B, or C selected as described above, and an obstacle is obtained by measuring the horizontal position using the right image of the right camera 11 and the left image of the left camera 12. The distance to a certain preceding vehicle is calculated by the distance data calculation unit 15 (S08).

  In the above-described obstacle measurement, the POC method is used and executed with the same resolution.

  As described above, according to the obstacle measurement by the obstacle measurement device 10 of FIG. 1, when the vehicle is low speed, the three-dimensional distance measurement is performed at the maximum region C at the low frame rate and at the high speed. Since 3D distance measurement is performed at the frame rate and the minimum area A, the amount of calculation for parallax calculation per unit time is constant regardless of whether the vehicle speed is high or low, and the upper limit of the amount of calculation per unit time is specified Is done. For this reason, regardless of whether the parallax calculation is hardware processing or software processing, the processing amount is almost constant and does not increase. Therefore, the scale of both hardware processing and software processing does not increase, and the cost of the apparatus can be reduced.

  In general, when driving at a high speed, since the vehicle travels on a road with a large radius of curvature, such as an expressway, there are few obstacles to watch out for at the edge of the angle of view. Problems are unlikely to occur even when distance measurement is performed. On the other hand, when driving at low speeds, it is often the case that the car is mainly driven on ordinary roads, and it is expected that cars will jump out at intersections and pedestrians will jump out. By measuring the three-dimensional distance of the obstacle in the area C, the obstacle at the angle of view can be measured.

  <Second Embodiment>

  FIG. 6 is a block diagram schematically showing an obstacle measuring apparatus for a vehicle according to the second embodiment. FIG. 7 is a schematic diagram showing a region (a) processed by the first resolution conversion Q and a region (b) processed by the second resolution conversion R by the resolution conversion unit 14b of FIG. FIG. 8 is a schematic diagram showing a camera image and a three-dimensional measurement region by the obstacle measuring device of FIG. 6, and shows a case of low speed running (a) and a case of high speed running (b), (c).

  The obstacle measurement apparatus 20 of FIG. 6 is basically the same as FIG. 1 except that the image processing unit 14 includes a resolution conversion unit 14b as compared with FIG. Mainly explained.

  The resolution conversion unit 14 b converts the resolution of the image based on the vehicle speed detected by the vehicle speed sensor 16. That is, when the vehicle is traveling at a high speed (for example, s1 or more), the resolution conversion unit 14b performs the first resolution conversion Q as shown in FIG. As described above, image processing is executed at a high resolution limited to the center of the screen.

  Further, when the vehicle is traveling at a low speed (for example, s1 or less), the resolution conversion unit 14b performs the second resolution conversion R as shown in FIG. In this way, image processing is executed at a low resolution on the entire screen. For example, in the second resolution conversion R, pixels can be thinned to a resolution lower than that of the first resolution conversion Q.

  As shown in FIG. 8A, when the vehicle is traveling at a low speed, an area for performing the three-dimensional measurement is set on the entire screen as shown in area C in FIG. 2, and the entire screen is held at a low resolution and a constant frame rate. In this state, image processing is performed. Further, as shown in FIG. 8B, when traveling at high speed, a region where three-dimensional measurement is performed is limited to the center of the screen as in region A of FIG. Image processing is performed while maintaining the rate. In this case, as shown in FIG. 8C, it is preferable to perform image processing at a low resolution except for the central area A which is executed at a high resolution.

  The steps (S11 to S16) of measuring the distance between the vehicle and the obstacle by the above-described obstacle measuring device 20 will be described with reference to the flowchart of FIG.

  When the obstacle measurement is started in the vehicle equipped with the obstacle measuring device 20 of FIG. 6, first, the left and right images are input from the right camera 11 and the left camera 12 to the image correction unit 13 (S11), and the image is converted into the image correction unit. 13 is corrected (S12).

  Then, if the vehicle speed detected by the vehicle speed sensor 16 is a high speed equal to or higher than s1 (S13), the resolution conversion unit 14b performs the first resolution conversion Q, as shown in FIGS. 8B and 8C. Image processing is performed with high resolution using the central area A as a three-dimensional measurement area (S14). If the vehicle speed is a low speed of s1 or less (S13), the second resolution conversion R is performed, and image processing is performed at a low resolution with the area C of the entire screen as a three-dimensional measurement area as shown in FIG. Perform (S15).

  Next, in the region A or C described above, the distance data calculation unit 15 calculates the distance to the preceding vehicle that is an obstacle by measuring the horizontal position using the right image of the right camera 11 and the left image of the left camera 12 (S16). ).

  In the above obstacle measurement, the POC method is used and executed at the same frame rate.

  As described above, according to the obstacle measurement by the obstacle measuring device 20 in FIG. 6, the three-dimensional distance measurement is performed in the area of the entire screen with low resolution when the vehicle is low speed, and high resolution when the vehicle is high speed. In addition, 3D distance measurement is performed in a limited area, so the amount of parallax calculation per unit time is constant regardless of whether the vehicle speed is high or low, and the upper limit of the amount of calculation per unit time is specified . For this reason, regardless of whether the parallax calculation is hardware processing or software processing, the processing amount is almost constant and does not increase. Therefore, the scale of both hardware processing and software processing does not increase, and the cost of the apparatus can be reduced.

  In addition, since the limit distance that the vehicle can move to avoiding obstacles when traveling at low speed is closer than when traveling at high speed, the area of the object (preceding vehicle 2) occupies a large area and is subject to low resolution. An object can be detected.

  Next, another example when setting a three-dimensional measurement region in FIGS. 1 and 6 will be described with reference to FIGS.

  FIG. 10 is a schematic diagram showing a camera image and a three-dimensional measurement region by the obstacle measuring device of FIGS. 1 and 6, in the case of low speed running (a) and the case of high speed running (b), (c). Indicates.

  In the example of FIG. 10A, when the vehicle is traveling on the road 1 at a low speed, the left end region D and the right end region E of the screen 9 are selected as the three-dimensional measurement region. Thus, for example, when driving at a low speed on a general road, by measuring the distance of the obstacle at the angle of view end of the left end region D and the right end region E, it is possible to focus on measuring and monitoring cars and pedestrians due to jumping out.

  In the example of FIG. 10B, when the vehicle is traveling on the road 1 at a high speed, the upper region F of the screen 9 is selected as the three-dimensional measurement region. Thereby, for example, when traveling at high speed on an expressway, the distance measurement of the obstacle is limited to the upper part of the angle of view.

  In the example of FIG. 10C, when the vehicle is traveling on the road 1, the distance data to the preceding vehicle 2 is obtained, and the three-dimensional measurement region is dynamically set from the distance data and the vehicle speed. It is a thing. In this case, it is preferable to set the three-dimensional measurement region to a long distance range when traveling at high speed and to a short distance range when traveling at low speed. For example, when traveling at high speed, the distance G is limited to a distance range (for example, 80 to 100 m) in which the area G of the screen 9 is set as the three-dimensional measurement area.

  As described above, three-dimensional measurement can be performed appropriately according to changes in road conditions, vehicle flow, etc., by distinguishing from distance information on the road and dynamically changing the three-dimensional measurement area according to the vehicle speed. Can do. In this case, the distance data is preferably calculated by the SAD method.

  <Third Embodiment>

  FIG. 11 is a block diagram schematically showing an obstacle measurement system for a vehicle according to a third embodiment.

  The obstacle measurement system 30 in FIG. 11 includes, for example, the preceding vehicle 2 based on the distance information from the obstacle measurement device 10 or 20 in FIG. 1 or 6 and the distance data calculation unit 15 of the obstacle measurement devices 10 and 20. When the distance between the determination unit 31 for determining whether the distance between the vehicle and the preceding vehicle 2 is equal to or less than the set distance, a warning sound, a warning sound, a warning lamp, etc. And a warning unit 32 for informing the user.

  According to the obstacle measurement system 30 of FIG. 11, when the distance to the preceding vehicle 2 is less than the set distance and the vehicle approaches, the vehicle is operated by a warning from the warning unit 32 based on the distance information from the obstacle measurement devices 10 and 20. The person can pay attention to the danger and can perform the danger avoidance operation, and can reduce the cost of the obstacle measuring system 30 by reducing the cost of the obstacle measuring devices 10 and 20.

  As described above, the best mode for carrying out the present invention has been described. However, the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, the obstacle measuring devices 10 and 20 in FIGS. 1 and 6 or the obstacle measuring system 30 in FIG. 11 can be used by being mounted on a self-propelled vehicle such as an automobile or a train, but is not limited thereto. For example, it may of course be mounted on a robot or the like.

  7 to 9, the resolution of the image processing is changed to two levels. However, the resolution may be changed to three levels. In this case, when s1> s2, the vehicle speed is higher than s1. The resolution can be set to a low resolution at a vehicle speed s2 or less and an intermediate resolution at a vehicle speed s1 or less s2.

  In the obstacle measurement system 30 of FIG. 11, a warning is issued when the distance to the preceding vehicle 2 is equal to or less than the set distance. For example, the vehicle is controlled so as to automatically decelerate. May be.

It is a block diagram showing roughly the obstacle measuring device for vehicles of a 1st embodiment. It is a schematic diagram which shows the area | regions A, B, and C of the three-dimensional measurement which can be selected by the area | region selection part 14a of FIG. The relationship between the frame (a), the vehicle speed (b), the actual frame rate (≈image processing time) (c), and the time T of the three-dimensional measurement region (d) in the control by the obstacle measuring device 10 of FIG. It is a figure shown typically. It is a schematic diagram which shows the camera image and three-dimensional measurement area | region by the obstruction measuring device of FIG. 1, Comprising: The case (a) of low speed driving | running | working and the case (b) of high speed driving | running | working are shown. It is a flowchart for demonstrating the step which measures the distance between a vehicle and an obstruction by the obstruction measurement apparatus 10 of FIG. It is a block diagram showing roughly an obstacle measuring device for vehicles of a 2nd embodiment. It is a schematic diagram which shows the area | region (a) processed by the 1st resolution conversion Q and the area | region (b) processed by the 2nd resolution conversion R by the resolution conversion part 14b of FIG. It is a schematic diagram which shows the camera image and three-dimensional measurement area | region by the obstruction measuring device of FIG. 6, Comprising: The case (a) of low speed driving | running | working and the case (b), (c) of high speed driving | running | working are shown. It is a flowchart for demonstrating the step which measures the distance between a vehicle and an obstruction by the obstruction measurement apparatus 20 of FIG. It is a figure for demonstrating another example which sets a three-dimensional measurement area | region in 1st, 2nd embodiment, and shows the camera image and 3D measurement area | region by the obstruction measuring device of FIG. 1, FIG. It is a schematic diagram, and shows a case of low-speed running (a) and a case of high-speed running (b), (c). It is a block diagram which shows roughly the obstacle measuring system for vehicles of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10,20 Obstacle measurement apparatus 11 Right camera 12 Left camera 14 Image processing part 14a Area selection part 14b Resolution conversion part 15 Distance data calculation part 16 Vehicle speed sensor 30 Obstacle measurement system 31 Determination part 32 Warning part A, B, C 3 Dimensional measurement area D Left end area E Right end area F Upper area

Claims (13)

An obstacle measurement method for measuring the distance from a running object to an obstacle with a stereo camera,
The obstacle measurement method, wherein the obstacle measurement target area and the frame rate of the image by the stereo camera are changed according to the speed of the traveling object.   The obstacle measurement method according to claim 1, wherein the target area is limited to a part of a screen and the frame rate is increased when the traveling object is relatively fast.   The obstacle measuring method according to claim 1, wherein when the traveling object is relatively slow, the target area is set to substantially the entire screen to reduce the frame rate. An obstacle measurement method for measuring the distance from a running object to an obstacle with a stereo camera,
An obstacle measurement method, wherein the obstacle measurement target region and the resolution of an image obtained by the stereo camera are changed according to the speed of the traveling object.   The obstacle measurement method according to claim 4, wherein when the traveling object is relatively high speed, the target area is limited to a part of a screen and the resolution is increased.   The obstacle measurement method according to claim 4, wherein when the traveling object is relatively low speed, the target area is substantially the entire screen and the resolution is reduced.   The obstacle measurement method according to any one of claims 1 to 6, wherein the distance in the distance measurement is calculated using a POC method (phase-only correlation method).   The obstacle measurement method according to any one of claims 1 to 7, wherein the target area is changed based on the speed and a distance to the obstacle.   The obstacle measuring method according to claim 8, wherein a distance to the obstacle when changing the target area is performed using a SAD (sum of absolute differences) method. An obstacle measuring device that measures the distance from a running object to an obstacle with a stereo camera,
Means for changing the obstacle measurement target area based on the speed of the traveling object;
Means for changing a frame rate of an image obtained by the stereo camera based on the speed. An obstacle measuring device that measures the distance from a running object to an obstacle with a stereo camera,
Means for changing the obstacle measurement target area based on the speed of the traveling object;
Means for changing the resolution of an image obtained by the stereo camera based on the speed, and an obstacle measuring device.   The obstacle measuring device according to claim 10 or 11 configured to execute the obstacle measuring method according to any one of claims 1 to 9.   An obstacle measurement device according to any one of claims 10 to 12, a determination unit that determines a risk related to the obstacle based on the measured distance information, and a warning when the risk is determined. An obstacle measuring system comprising: a warning unit that emits.

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