Device for detecting relative angles of articulated vehicles

Abstract

To provide a relative angle detector for a combination vehicle that can detect the relative angle of a vehicle to be towed with respect to a towing vehicle without installing a mark of an imaging object for detecting the relative angle between the vehicle to be towed and the towing vehicle.SOLUTION: A relative angle detector 6 is used for a combination vehicle 1 in which a towing vehicle 2 and a vehicle to be towed 3 are connected with a towing-side connection member 4 and a towed-side connection member 5, and comprises: an imaging apparatus 61 that, from one side of the towing vehicle 2 and the vehicle to be towed 3, picks up an image of the other side; an illumination device 62 that irradiates a position to be imaged by the imaging apparatus 61 with marker light; and an image analysis device 63 that analyzes the image picked up by the imaging apparatus 61 to detect the relative angle of the vehicle to be towed 3 with respect to the towing vehicle 2.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a relative angle detection device for a combination vehicle, which is used in a combination vehicle in which a towed vehicle is towed by a towing vehicle, and which detects the relative angle of the towed vehicle to the towing vehicle. [Background technology]

[0002] 2. Description of the Related Art Some conventional combination vehicles, which are formed by connecting a towed vehicle and a towing vehicle, are capable of detecting the hitch angle, which is the angle of the towed vehicle relative to the towing vehicle when the combination vehicle is viewed from above.

[0003] The trailering assist system described in Patent Document 1 captures an image of a target on the towed vehicle (trailer) using a camera located at the rear of the towing vehicle, and detects the hitch angle by analyzing the captured image. The target is a mark of a predetermined shape, such as an icon, located at the front of the towed vehicle. For example, Figure 1 of Patent Document 1 shows a panel with a cross-shaped graphic as the target. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent No. 9950738 Summary of the Invention [Problem to be solved by the invention]

[0005] In systems that detect the hitch angle based on an image of a target on the towed vehicle, such as the trailing assist system described in Patent Document 1, a target panel or sheet must be installed in front of the towed vehicle, which increases the installation burden of the system. In addition, installing the target may affect the external appearance of the towed vehicle.

[0006] Therefore, an object of the present invention is to provide a relative angle detection device for articulated vehicles that can detect the relative angle of a towed vehicle to a towing vehicle without installing an imaging target marker on the towed vehicle for detecting the relative angle with the towing vehicle. [Means for solving the problem]

[0007] In order to achieve the above object, the present invention is used in a combination vehicle in which a towing vehicle and a towed vehicle are connected by a towing-side connecting member and a towed-side connecting member, an imaging device attached to the towing vehicle for capturing an image of the towed vehicle; an illumination device that illuminates a marker light at a position to be imaged by the imaging device; and an image analysis device that analyzes the image captured by the imaging device and detects the relative angle of the towed vehicle with respect to the towing vehicle; and an illumination range of the marker light by the illumination device includes the towed side connecting member and the road surfaces on both sides of the towed side connecting member in the vehicle width direction of the towing vehicle. The present invention provides a relative angle detection device for articulated vehicles. [Effects of the Invention]

[0008] According to the present invention, it is possible to detect the relative angle of the towed vehicle with respect to the towing vehicle without installing a marker on the towed vehicle to be imaged for detecting the relative angle with respect to the towing vehicle. [Brief explanation of the drawings]

[0009] [Figure 1] 1A to 1C are schematic diagrams showing articulated vehicles as targets for relative angle detection according to an embodiment of the present invention. [Figure 2] 1A is a structural diagram showing an example of the structure of a towing side connecting member and a towed side connecting member, and FIG. 1B is a cross-sectional view showing a state in which the towing side connecting member and the towed side connecting member are combined. [Figure 3] FIG. 2 is a block diagram showing the functional configuration of the relative angle detection device. [Figure 4] 10 is a flowchart illustrating an example of a procedure of a process performed by the relative angle detection device. [Figure 5] 1A and 1B are explanatory diagrams showing the positions of an imaging device and an illumination device in an articulated vehicle according to the first embodiment. [Figure 6]1A and 1B are explanatory diagrams illustrating images captured by the imaging device according to the first embodiment. [Figure 7] FIG. 10 is an explanatory diagram showing the positions of an imaging device and an illumination device in an articulated vehicle according to a second embodiment. [Figure 8] 10(a) to 10(d) are explanatory diagrams showing a state in which a towed vehicle illuminated with marker light from an illumination device according to a second embodiment is viewed from the towing vehicle side. [Figure 9] FIG. 10 is an explanatory diagram showing the positions of an imaging device and an illumination device in an articulated vehicle according to a third embodiment. [Figure 10] 10(a) to 10(c) are explanatory diagrams showing a towed vehicle illuminated with marker light from an illumination device according to a third embodiment, as viewed from the towing vehicle side. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Embodiment Mode] The following description of the preferred embodiments of the present invention will be made with reference to the accompanying drawings. The following embodiments and examples are presented as preferred examples for carrying out the present invention, and while some examples specifically exemplify various technically preferred aspects, the technical scope of the present invention is not limited to these specific examples.

[0011] Figures 1(a) to 1(c) are schematic diagrams showing an articulated vehicle 1 equipped with a relative angle detection device, to which a relative angle detection device according to an embodiment of the present invention is attached. Figure 1(a) shows the articulated vehicle 1 as viewed from above, and Figure 1(b) shows the left side of the articulated vehicle 1 relative to the forward direction of the articulated vehicle 1. Figure 1(c) shows the articulated vehicle 1 as viewed from the rear. In addition, in Figures 1(a) and 1(b), the center line 2a of the towing vehicle 2, which runs along the fore-and-aft direction of the towing vehicle 2, and the center line 3a of the towed vehicle 3, which runs along the fore-and-aft direction of the towed vehicle 3, are each shown by a dashed dotted line.

[0012] Articulated vehicle 1 has a towing vehicle 2 and a towed vehicle 3, which are connected to each other by a towing-side connecting member 4 and a towed-side connecting member 5. In Figures 1(a) to 1(c), the towed vehicle 3 is shown as a box-shaped camper, but the towed vehicle is not limited to this and may also be, for example, a boat trailer carrying a boat. Furthermore, towing vehicle 2 may be a manually operated vehicle in which a driver performs steering and other driving operations, or it may be an automatically operated vehicle in which some or all of the driving operations are performed automatically.

[0013] Fig. 2(a) is a structural diagram showing an example of the structure of the towing side connecting member 4 and the towed side connecting member 5. Fig. 2(b) is a cross-sectional view showing the towing side connecting member 4 and the towed side connecting member 5 in a combined state.

[0014] The towing-side connecting member 4 has a hitch cross member 41 arranged along the vehicle width direction of the towing vehicle 2, a pair of hitch side members 42 fixed to both ends of the hitch cross member 41, a ball mount 43 provided to protrude from the center of the hitch cross member 41 in the vehicle width direction toward the rear of the towing vehicle 2, a hitch pin 44 protruding upward from the ball mount 43, and a spherical hitch ball 45 provided integrally with the upper end of the hitch pin 44. The hitch cross member 41 and the pair of hitch side members 42 are arranged inside the rear bumper 21 of the towing vehicle 2, and the ball mount 43, hitch pin 44, and hitch ball 45 are exposed rearward from the rear bumper 21. The pair of hitch side members 42 are fixed to the body of the towing vehicle 2 with a plurality of bolts.

[0015] The towed-side connecting member 5 has a coupler 51 that covers the hitch ball 45, a latch mechanism 52 that prevents the coupler 51 from coming off the hitch ball 45, a rod-shaped tongue 53 to the tip of which the coupler 51 is fixed, and a pair of side beams 54 that extend in a direction inclined relative to the longitudinal direction of the tongue 53. One end of each of the side beams 54 is connected to the tongue 53. The base end of the tongue 53 and the other end of each of the pair of side beams 54 are connected to the chassis of the towed vehicle 3.

[0016] 2(b), the coupler 51 has a cup portion 511 that accommodates the hitch ball 45. The latch mechanism 52 has a lever support 520, a lever 521 that is rotated relative to the lever support 520, a latch plate 522 that faces the upper surface 51a of the coupler 51, a latch bar 523 that gets in between the upper surface 51a of the coupler 51 and the latch plate 522 when the lever 521 is operated, a lock plate 524 that receives the hitch ball 45 from below, a coil spring 525 that urges the lock plate 524 downward, and a bolt 526 and a nut 527 that connect the latch plate 522 and the lock plate 524.

[0017] The locking plate 524 is rotatable around a support pin 512 provided on the coupler 51. When the lever 521 is operated as shown by arrow A in FIG. 2(b), the latch plate 522 is lifted upward relative to the coupler 51 by the latch bar 523, and the locking plate 524 prevents the hitch ball 45 from coming off. The inner surface 511a of the cup portion 511 of the coupler 51 is a concave spherical surface with a curvature corresponding to the curvature of the surface 45a of the hitch ball 45. The sliding between the inner surface 511a of the cup portion 511 and the surface 45a of the hitch ball 45 allows the coupler 51 to swing in any direction around the hitch ball 45.

[0018] In combination vehicle 1, the relative angle of towed vehicle 3 to towing vehicle 2 changes in various ways, and particularly when backing up with towed vehicle 3 in front in the direction of travel, the relative angle of towed vehicle 3 to towing vehicle 2 is an important indicator for driving operations. For this reason, combination vehicle 1 uses a relative angle detection device 6. If towing vehicle 2 is a manually driven vehicle (non-autonomous vehicle), an image showing the detection results of relative angle detection device 6 is displayed on a display located inside the cabin of towing vehicle 2 to assist the driver in driving operations. Furthermore, if towing vehicle 2 is an autonomous vehicle, towing vehicle 2 is automatically steered based on the detection results of relative angle detection device 6.

[0019] The relative angles of the towed vehicle 3 to the towing vehicle 2 include a hitch angle, which indicates the horizontal inclination of the towed vehicle 3 relative to the towing vehicle 2; a relative pitch angle, which indicates the vertical inclination of the towed vehicle 3 relative to the towing vehicle 2; and a relative roll angle, which is the difference between the roll angles of the towing vehicle 2 and the towed vehicle 3. Figure 1(a) shows the hitch angle θh when the towed vehicle 3 is tilted to the left relative to the towing vehicle 2. Figure 1(b) shows the relative pitch angle θp when the towed vehicle 3 is tilted upward relative to the towing vehicle 2. Figure 1(c) shows the relative roll angle θr when the towed vehicle 3 is tilted clockwise relative to the towing vehicle 2 as viewed from the rear of the combination vehicle 1.

[0020] The relative angle detection device 6 according to this embodiment can detect at least the hitch angle and the relative pitch angle among the hitch angle, the relative pitch angle, and the relative roll angle. Next, the configuration, arrangement, and operation of the relative angle detection device 6 will be described.

[0021] 3 is a block diagram showing the functional configuration of the relative angle detection device 6. The relative angle detection device 6 includes an imaging device 61 that captures images of the towing vehicle 2 and the towed vehicle 3 from one side to the other, an illumination device 62 that illuminates a marker light at a position imaged by the imaging device 61, and an image analysis device 63 that analyzes the image captured by the imaging device 61 to detect the relative angle of the towed vehicle 3 with respect to the towing vehicle 2.

[0022] The irradiation device 62 projects a figure of a predetermined shape using marker light. Here, the figure refers to a line segment of a predetermined length, a curved or broken line, a closed curve such as a polygon or ellipse, or one or more points. A laser beam with excellent linearity is used as the marker light. The color of the marker light is not particularly limited, and for example, a blue, red, or green visible laser beam can be used as the marker light. In this case, a visible light camera is used as the imaging device 61. The marker light may be invisible light such as infrared light or ultraviolet light. In this case, an infrared camera or other device capable of capturing an image of light with the wavelength of the marker light is used as the imaging device 61.

[0023] The imaging device 61 captures an image of the graphic projected by the marker light emitted by the illumination device 62, and detects the relative angle of the towed vehicle 3 with respect to the towing vehicle 2 based on the shape of the captured image. The relative angle detection result is sent to, for example, the display device 7 of the towing vehicle 2, and an image showing the detection result of the relative angle detection device 6 is displayed on a display 71 inside the vehicle cabin, as shown in FIG. 3. FIG. 3 shows an example of a display in a first display area 71a of the display 71, in which an overhead image 710 is displayed showing a graphic symbol 711 representing the towing vehicle 2 and a graphic symbol 712 representing the towed vehicle 3, tilted in accordance with the hitch angle detected by the relative angle detection device 6. An image captured by the imaging device 61, for example, is displayed in a second display area 71b of the display 71.

[0024] The driver performs steering operations while taking into consideration the contents displayed on the display 71. The display 71 may also display an image showing the recommended direction of steering wheel rotation according to the hitch angle detected by the relative angle detection device 6. Furthermore, if the towing vehicle 2 is an autonomous vehicle, the detection results of the relative angle detection device 6 are output to the autonomous driving device 8.

[0025] The illumination device 62 illuminates a marker light at least when the combination vehicle 1 is reversing. If the towing vehicle 2 is a manually driven vehicle, the illumination device 62 illuminates a marker light, for example, when the shift lever is shifted into R (reverse) range, and stops illuminating the marker light when the shift lever is shifted from R range to another range. The illumination device 62 may also illuminate a marker light in response to a switch operation by the driver. Even when the combination vehicle 1 is moving forward, the state of the towed vehicle 3 may become unstable due to, for example, a slope of the road or a crosswind. In such cases, the illumination device 62 illuminates a marker light in response to a switch operation by the driver, and the relative angle detection device 6 detects the hitch angle, etc., thereby assisting the driver in their driving operation. If the towing vehicle 2 is an autonomous vehicle, the illumination device 62 starts and stops illuminating a marker light in response to a command signal from the autonomous driving device 8.

[0026] 4 is a flowchart showing an example of the procedure of processing performed by the relative angle detection device 6. The relative angle detection device 6 repeatedly executes the processing shown in this flowchart at a predetermined cycle of, for example, several ms to several tens of ms.

[0027] The relative angle detection device 6 first determines whether or not to execute processing to detect the relative angle of the towed vehicle 3 with respect to the towing vehicle 2 (step S1). As described above, this determination can be made, for example, by the driver's driving operation or switch operation for backing up, or by a command signal from the automatic driving device 8. If the result of this determination is Yes, the illumination device 62 illuminates marker light (step S2), and the imaging device 61 captures an image of the figure projected by the marker light (step S3). Information on the image captured by the imaging device 61 is sent to the image analysis device 63.

[0028] The image analyzer 63 analyzes the image captured by the imaging device 61 and detects the relative angle of the towed vehicle 3 with respect to the towing vehicle 2 (step S4). This analysis in step S4 can be performed, for example, by pre-storing the shape of the marker light when the hitch angle, relative pitch angle, and relative roll angle are all zero as a reference shape, comparing this reference shape with the shape of the marker light in the image captured by the imaging device 61 to determine the amount of change in the shape, and converting this amount of change into a relative angle. Note that the relative angle in the current cycle may be detected by referring to the result of relative angle detection in the previous cycle.

[0029] On the other hand, if the result of the determination in step S1 is No, the irradiation device 62 stops emitting the marker light (step S5), and the image analysis device 63 initializes the detection result of the relative angle (step S6). [Example]

[0030] Next, first to third embodiments of the relative angle detection device 6 will be described in more detail.

[0031] [Example 1] 5(a) and (b) are explanatory diagrams showing the positions of the imaging device 61 and the illumination device 62 in the combination vehicle 1 according to the first embodiment. Fig. 5(a) shows the rear side of the towing vehicle 2 as seen from the towed vehicle 3 side. Fig. 5(b) shows the towing side coupling member 4 and the towed side coupling member 5 as seen from the left side of the towing vehicle 2, as well as portions of the towing vehicle 2 and the towed vehicle 3.

[0032] In the first embodiment, the imaging device 61 and the illumination device 62 are attached to the rear end of the towing vehicle 2. More specifically, the imaging device 61 and the illumination device 62 are attached to the outside of the back door 22 of the towing vehicle 2. The illumination device 62 is attached to a position between the license plate 23 and the rear window 221 of the back door 22. The imaging device 61 is disposed above the illumination device 62 and captures an image of the towed vehicle 3. In the example shown in FIG. 5(a), the imaging device 61 is disposed directly above the illumination device 62, but the position of the imaging device 61 may be offset from the illumination device 62 in the vehicle width direction of the towing vehicle 2.

[0033] In this example, the figure projected by the marker light emitted by the illumination device 62 is a line segment of a predetermined length parallel to the vehicle width direction of the towing vehicle 2. FIG. 5(a) shows the angle of view VA, which indicates the imaging range of the imaging device 61, and the illumination range R of the marker light of the illumination device 62. In FIG. 5(b), the direction of the marker light emitted by the illumination device 62 is indicated by a dashed-dotted line DL. The illumination range of the marker light emitted by the illumination device 62 includes the towed coupling member 5 and the road surface 9 on both sides of the towed coupling member 5 in the vehicle width direction of the towing vehicle 2. In this example, the illumination device 62 illuminates the tongue 53 of the towed coupling member 5, but this is not limiting and the illumination may also be directed to the coupler 51, for example. The angle of view VA of the imaging device 61 includes the entire illumination range R of the illumination device 62. The road surface 9 is, for example, the surface of a paved public road, but may also be unpaved ground or the surface of a parking space in a parking lot.

[0034] 6(a) and (b) are explanatory diagrams showing images captured by the imaging device 61. In the following description, the right side and left side refer to the right and left sides of the image captured by the imaging device 61. FIG. 6(a) shows a state in which the towing vehicle 2 and the towed vehicle 3 are aligned in a straight line with a hitch angle of zero. FIG. 6(b) shows a state in which the towed vehicle 3 is tilted to the right relative to the towing vehicle 2.

[0035] Since the imaging device 61 is positioned higher than the illumination device 62, in the image captured by the imaging device 61, the first illumination section 621, which shows the marker light that hits the towed side connecting member 5, appears higher than the second illumination section 622, which shows the marker light that hits the road surface 9 on the left side of the towed side connecting member 5, and the third illumination section 623, which shows the marker light that hits the road surface 9 on the right side of the towed side connecting member 5.

[0036] 6(a) and 6(b), the overall length of the first to third irradiation units 621-623 in the left-right direction of the image captured by the imaging device 61 is indicated as L0, the length of the first irradiation unit 621 is indicated as L1, the length of the second irradiation unit 622 is indicated as L2, and the length of the third irradiation unit 623 is indicated as L3. More specifically, the length L1 is the length between the left end and the right end of the portion of the tongue 53 irradiated by the irradiation device 62. The length L2 is the length from the left end of the road surface 9 irradiated by the irradiation device 62 to the left end of the portion of the tongue 53 irradiated by the irradiation device 62. The length L3 is the length from the right end of the road surface 9 irradiated by the irradiation device 62 to the right end of the portion of the tongue 53 irradiated by the irradiation device 62. The length L0 is the length from the left end to the right end of the road surface 9 irradiated by the irradiation device 62. The lengths L1, L2, and L3 are index values ​​that indicate the position of the towed side connecting member 5 in the vehicle width direction within the irradiation range (length L0) of the marker light.

[0037] When the midpoint of length L0 in the image captured by the imaging device 61 is taken as the reference position, the left-right central position of the tongue 53 relative to this reference position can be found using the formula L0 / 2 - ((L2 + L1 / 2) / (L1 + L2 + L3)) × L0. Furthermore, because the positional relationships between the imaging device 61, the illumination device 62, the hitch ball 45, etc. are known, the hitch angle can be calculated based on the above formula. In this way, the image analysis device 63 detects the hitch angle of the combination vehicle 1 from the position of the towed coupling member 5 in the vehicle width direction within the illumination range of the marker light.

[0038] Furthermore, in the image captured by the imaging device 61, the vertical distance D between the first illuminating unit 621 and the second and third illuminating units 622 and 623 changes depending on the relative pitch angle, so the relative pitch angle can be determined based on this distance D. Distance D is an index value that indicates the difference in the longitudinal position of the towing vehicle 2 between the towed connecting member 5 illuminated by the marker light and the road surface 9. In other words, the image analyzing device 63 detects the relative pitch angle of the combination vehicle 1 from the difference in the longitudinal position of the towing vehicle 2 between the towed connecting member 5 illuminated by the marker light and the road surface 9.

[0039] The image analysis device 63 acquires image information from the imaging device 61 at a predetermined cycle, calculates the hitch angle and relative pitch angle, and outputs the results as detection results. As the hitch angle increases, the marker light also shines on the left and right sides of the tongue 53, and the length L1 of the first irradiation section 621 increases. Therefore, in the calculation to determine the hitch angle, it is necessary to correct the left-right center position of the tongue 53, for example, by using the hitch angle calculated in the previous cycle. This correction may also be performed by referring to map information that stores the relationship between the calculation results using the above calculation formula and the actual left-right center position of the tongue 53.

[0040] [Example 2] FIG. 7 is an explanatory diagram showing the positions of an imaging device 61 and an illumination device 62 in an articulated vehicle 1 according to a second embodiment. In this example, the imaging device 61 is attached to the rear end of the towing vehicle 2 as in the first embodiment, but the illumination device 62 is attached to the towed-side coupling member 5. The illumination device 62 is fixed to the tongue 53 by a bracket 55 and illuminates the front end of the towed vehicle 3 diagonally upward. In FIG. 7, the illumination range of the marker light emitted by the illumination device 62 is indicated by two dash-dotted lines DL1 and DL2. The imaging device 61 is attached between the license plate 23 and the rear window 221 of the back door 22, and is also used as a camera for a backside monitor.

[0041] Figures 8(a) to 8(d) are explanatory diagrams showing the towed vehicle 3 illuminated with marker light from the illumination device 62 as viewed from the towing vehicle 2. Figure 8(a) shows a state where the hitch angle, relative pitch angle, and relative roll angle are all zero. Figure 8(b) shows a state where the towed vehicle 3 is tilted to the right as viewed from the towing vehicle 2. Figure 8(c) shows a state where the towed vehicle 3 is tilted upward. Figure 8(d) shows a state where the towed vehicle 3 is rolling counterclockwise.

[0042] In this example, the projection figure 624 projected by the marker light emitted by the illumination device 62 is an ellipse whose major axis is in the width direction of the towing vehicle 2 and whose minor axis is in the up-down direction. In FIG. 8(a), the major axis of the projection figure 624 is D 11 and the minor axis is D 12 This major diameter D 11 and minor diameter D 12 The shape of the ellipse indicated by is the reference shape of the projection figure 624. The image analyzer 63 calculates the major diameter D 11 and minor diameter D 12 is stored.

[0043] As shown in FIG. 8(b), when the towed vehicle 3 tilts left or right relative to the towing vehicle 2, the shape of the projected figure 624 captured by the imaging device 61 is distorted, and the major axis D 21 is the major axis D of the projection figure 624 shown in FIG. 11This major diameter D 21 and major diameter D 11 The difference between these is the amount of distortion of the projected figure 624 due to the change in hitch angle. The image analysis device 63 can calculate the hitch angle of the articulated vehicle 1 by converting this amount of distortion into a hitch angle. That is, in this example, the image analysis device 63 detects the hitch angle based on the size of the marker light captured by the imaging device 61 in the vehicle width direction of the towing vehicle 2.

[0044] As shown in FIG. 8(c), when the towed vehicle 3 tilts up or down relative to the towing vehicle 2, the shape of the projected figure 624 captured by the imaging device 61 is distorted, and the minor axis D 32 is the minor axis D of the projection figure 624 shown in FIG. 12 This minor diameter D 32 and minor axis D 12 The difference between this and the relative pitch angle is the amount of distortion of the projected figure 624 due to the change in the relative pitch angle. The image analysis device 63 converts this amount of distortion into a relative pitch angle, thereby determining the relative pitch angle of the articulated vehicle 1. That is, in this example, the image analysis device 63 detects the relative hitch angle based on the vertical size of the marker light captured by the imaging device 61 on the towing vehicle 2.

[0045] As shown in FIG. 8(d), when the towed vehicle 3 rolls relative to the towing vehicle 2, the shape of the projected figure 624 captured by the imaging device 61 tilts with respect to the reference shape. In FIG. 8(d), the tilt angle of the major axis of the projected figure 624 with respect to the reference shape is indicated by θ. This tilt angle θ is the amount of distortion of the projected figure 624 due to the relative roll angle, and the image analysis device 63 can determine the relative roll angle of the combination vehicle 1 by converting this tilt angle θ into a relative roll angle. That is, in this example, the image analysis device 63 detects the relative hitch angle based on the tilt of the towing vehicle 2 of the marker light captured by the imaging device 61.

[0046] [Example 3] Fig. 9 is an explanatory diagram showing the positions of the imaging device 61 and the illumination device 62 in an articulated vehicle 1 according to Example 3. In this example, the imaging device 61 and the illumination device 62 are attached to the rear end of the towing vehicle 2 as in Example 1, but the illumination device 62 illuminates the towed vehicle 3 rather than the towed coupling member 5. In Fig. 9, the illumination range of the marker light emitted by the illumination device 62 is indicated by two dashed dotted lines DL3 and DL4.

[0047] The imaging device 61 captures an image of the portion of the towed vehicle 3 that is illuminated by the marker light from the illumination device 62. As in the second embodiment, the image analysis device 63 detects the hitch angle, relative pitch angle, and relative roll angle based on the widthwise size, vertical size, and tilt of the marker light captured by the imaging device 61.

[0048] However, because the illumination device 62 is attached to the towing vehicle 2, the shape of the marker light captured by the imaging device 61 is less likely to change depending on the hitch angle, etc., compared to Example 2. For this reason, in this example, the illumination device 62 illuminates the towed vehicle side at a position and range where a portion of the marker light captured by the imaging device 61 is missing depending on the magnitude of the hitch angle.

[0049] 10(a) to 10(c) are explanatory diagrams showing the towed vehicle 3 illuminated with marker light from the illumination device 62 as viewed from the towing vehicle 2 side. FIG. 10(a) shows the state when the hitch angle is zero. FIG. 10(b) shows the towed vehicle 3 tilted to the right as viewed from the towing vehicle 2 side, and FIG. 10(c) shows the towed vehicle 3 tilted to the left as viewed from the towing vehicle 2 side. The shape of the projection figure 625 projected by the marker light illuminated by the illumination device 62 is elliptical, as in the second embodiment.

[0050] 10(a), when the hitch angle is zero, the entire elliptical shape of the projected figure 625 is captured by the imaging device 61, but if the towed vehicle 3 tilts left or right relative to the towing vehicle 2, a portion of the long axis of the projected figure 625 becomes lost and deviates from the front end of the towed vehicle 3, changing the shape of the projected figure 625 and shortening the length of the projected figure 625 in the width direction of the towing vehicle 2. The image analyzer 63 can accurately determine the hitch angle from the amount of change in the shape of the projected figure 625.

[0051] (Effects of the embodiment and examples 1 to 3) According to the above-described embodiment and Examples 1 to 3, the marker light emitted by the illumination device 62 is captured by the imaging device 61, and the image analysis device 63 detects the relative angle of the towed vehicle 3 with respect to the towing vehicle 2 by analyzing the captured image, so it is possible to detect the relative angle of the towed vehicle 3 with respect to the towing vehicle 2 without installing markers such as panels or sheets on the towed vehicle 3.

[0052] (Addendum) The present invention has been described above based on embodiments and examples, but these embodiments and examples do not limit the scope of the invention claimed. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. Furthermore, the present invention can be implemented by omitting some components, or by adding or substituting components, as appropriate, without departing from the spirit of the invention. For example, the present invention can be implemented by modifying it as follows.

[0053] In the above embodiment and example, the imaging device 61 is attached to the towing vehicle 2 to capture images of the towed vehicle 3, but the imaging device 61 may alternatively be attached to the towed vehicle 3 and capture images of the towing vehicle 2. In this case, the illumination device 62 illuminates marker light from the towed vehicle 3 toward the towing vehicle 2.

[0054] In the above-mentioned Examples 2 and 3, the projection figures 624, 625 are described as having an elliptical shape, but the shape of the projection figures 624, 625 is not limited to this, and may be, for example, a polygon or a broken line, as long as it has a predetermined length in the width direction and vertical direction of the towing vehicle 2. [Explanation of symbols]

[0055] 1... Articulated vehicle 2... Towing vehicle 3...Towed vehicle 4...Towing side connecting member 5... Towed side connecting member 6... Relative angle detection device 61...imaging device 62...illumination device 63...Image analysis device

Claims

1. The towing vehicle and the towed vehicle are connected by a towing-side connecting member and a towed-side connecting member, an imaging device attached to the towing vehicle for imaging the towed vehicle; an illumination device attached to the towing vehicle and configured to illuminate a marker light at a position to be imaged by the imaging device; an image analysis device that analyzes the image captured by the imaging device and detects the relative angle of the towed vehicle with respect to the towing vehicle, the illumination range of the marker light by the illumination device includes the towed side connecting member and the road surfaces on both sides of the towed side connecting member in the vehicle width direction of the towing vehicle; A relative angle detection device for articulated vehicles.

2. the relative angle detected by the image analysis device includes a hitch angle of the combination vehicle; The relative angle detection device for articulated vehicles according to claim 1.

3. the illumination device illuminates the marker light when the combination vehicle is moving backward. The relative angle detection device for articulated vehicles according to claim 1.

4. the image analysis device detects the hitch angle of the combination vehicle based on the position of the towed-side connecting member in the vehicle width direction within the illumination range of the marker light. The relative angle detection device for articulated vehicles according to claim 1.

5. the image analysis device detects the pitch angle of the towed vehicle relative to the towing vehicle based on the difference in the longitudinal position of the towing vehicle between the towed-side connecting member illuminated by the marker light and the road surface. The relative angle detection device for articulated vehicles according to claim 1.

Images