A vehicle blind spot monitoring method based on electronic outside mirror

Abstract

The application provides a vehicle blind area monitoring method based on electronic outside rearview mirror, a kinematic model is established for a towing vehicle and a trailer, the trajectories of the towing vehicle and the trailer are accurately calculated respectively, the rear field of view is spliced by using the relative position relationship through the left and right cameras of the electronic outside rearview mirror and the rear camera at the rear of the trailer compartment, the transparent display of the trailer compartment is realized, and thus the monitoring of the field of view blind area is realized, and the driving safety is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic outside rearview mirror, and particularly to a vehicle blind area monitoring method based on electronic outside rearview mirror. BACKGROUND

[0002] The electronic outside rearview system is a monitoring system which collects road video by a digital camera and displays the video on a high-definition digital display screen after video processing. The system has the advantages of large visual range, good imaging in low-illumination or rainy and foggy weather, less blind area, less wind resistance and wind noise, and is gradually widely used, including some large trucks. The trailer is a non-powered wheeled vehicle towed by an ordinary vehicle. Even for experienced drivers, it is quite challenging to control the trailer, especially to control the trailer to reverse, and the driver can hardly see the obstacles behind the trailer through the limited visual range of the electronic outside rearview mirror.

[0003] In order to increase the environmental perception ability of the large truck, some scholars have proposed a scheme of increasing perception sensors (such as laser radar and millimeter wave radar) on the trailer and the towing vehicle respectively. However, the implementation cost is high, and since the large truck is basically a fuel vehicle, its intelligentization and electrification degree are not as good as that of a passenger vehicle, and it cannot meet the demand of laser radar and other perception sensors for power consumption and computing power, resulting in difficulty in landing the scheme. SUMMARY

[0004] The present application provides a vehicle blind area monitoring method based on electronic outside rearview mirror, which aims to solve the defects in the prior art, monitor the visual blind area, and improve driving safety.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0006] The present application provides a vehicle blind area monitoring method based on electronic outside rearview mirror, which includes:

[0007] Step 1, acquiring the current state parameters of the towing vehicle, including: the towing vehicle speed, the steering wheel angle, the steering ratio of the steering wheel and the front wheels of the towing vehicle, and the yaw angle of the towing vehicle;

[0008] Step 2, acquiring the pose of the towing vehicle at the previous time, and calculating the current position coordinates of the towing vehicle body corner points and the left camera, the right camera and the rear camera according to the current state parameters;

[0009] Step 3, determining the visual visible area and the visual blind area of the left camera and the right camera according to the current position coordinates of the towing vehicle body corner points and the left camera and the right camera respectively;

[0010] Step 4, according to the turning direction of the vehicle and the visual blind area, cutting the corresponding compensation image from the rear camera image;

[0011] Step 5, scaling the field of view visible area images of the left camera and the right camera, the compensation image according to a preset ratio;

[0012] Step 6, splicing the scaled field of view visible area images of the left camera and the right camera, the compensation image according to a preset rule to generate a perspective image, and displaying the perspective image on the left and right display screens of the electronic outside rearview mirror.

[0013] Specifically, the step 2 comprises:

[0014] Step 201, acquiring the body parameters of the tractor and the trailer;

[0015] Step 202, establishing a kinematic model of the tractor and the trailer according to Ackerman kinematics;

[0016] Step 203, acquiring the pose of the tractor at a previous time, and calculating the pose of the tractor at a current time according to a first preset relationship;

[0017] Step 204, determining the motion state parameters of the articulation point at the current time, including the speed of the articulation point and the heading angle of the speed direction;

[0018] Step 205, determining the motion state parameters of the trailer at the current time according to the motion state parameters of the articulation point at the current time, including the speed of the trailer rear axle center, the trailer angular velocity, the heading angle of the trailer at the current time, and the pose of the trailer at the current time;

[0019] Step 206, determining the body corner point coordinates of the tractor and the trailer according to the body parameters of the tractor and the trailer, the pose of the tractor at the current time, and the pose of the trailer at the current time;

[0020] Step 207, determining the current position coordinates of the left camera, the right camera, and the rear camera according to the body corner point coordinates of the tractor and the trailer.

[0021] Specifically, the first preset relationship is:

[0022]

[0023] wherein, is the pose of the tractor at the current time, is the pose of the tractor at a previous time, v is the speed of the tractor, L1 is the wheelbase of the tractor, δ is the angle of the front wheel of the tractor, ϑ is the steering wheel angle, k is the steering ratio of the steering wheel and the front wheel of the tractor, and △t is the sampling time interval.

[0024] Specifically, the step 204 comprises:

[0025] Step A1, determining the heading angle of the hinge point speed direction according to a second preset relationship, the second preset relationship is:

[0026]

[0027] Wherein, θ is the heading angle of the hinge point speed direction, d is the distance between the hinge point and the center of the rear axle of the tractor, R1 is the turning radius of the tractor, L1 is the wheelbase of the tractor, and δ is the angle of the front wheel of the tractor;

[0028] Step A2, determining the speed of the hinge point according to a third preset relationship, the third preset relationship is:

[0029]

[0030] Wherein, V P is the speed of the hinge point, v is the speed of the tractor, and θ is the heading angle of the hinge point speed direction;

[0031] Step A3, determining the position of the hinge point at the current time according to the pose of the tractor at the current time through a fourth preset relationship, the fourth preset relationship is:

[0032]

[0033] Wherein, is the pose of the tractor at the current time, is the position of the tractor at the current time, and d is the distance between the hinge point and the center of the rear axle of the tractor.

[0034] Specifically, the step 205 comprises:

[0035] Step B1, determining the speed of the center of the rear axle of the trailer according to a fifth preset relationship, the fifth preset relationship is:

[0036]

[0037] Wherein, is the speed of the center of the rear axle of the trailer, V P is the speed of the hinge point, θ is the heading angle of the hinge point speed direction, and λ k-1 is the included angle between the heading direction of the tractor and the heading direction of the trailer;

[0038] Step B2, determining the angular velocity of the trailer rotation according to a sixth preset relationship, the sixth preset relationship is:

[0039]

[0040] Wherein, ω2 is the angular velocity of the trailer rotation, and L2 is the wheelbase of the trailer;

[0041] Step B3, determining the heading angle of the trailer at the current time according to a seventh preset relationship, the seventh preset relationship being:

[0042]

[0043] wherein, is the heading angle of the trailer at the current time, is the sampling time interval of the system.

[0044] Step B4, determining the pose of the trailer at the current time according to an eighth preset relationship, the eighth preset relationship being:

[0045]

[0046] wherein, L2 is the wheelbase of the trailer.

[0047] Specifically, the step 3 comprises:

[0048] Step 301, determining the field of view dividing line of the left camera and the right camera according to the turning direction of the vehicle;

[0049] Step 302, determining the field of view blind area according to the field of view dividing line.

[0050] Specifically, the step 301 comprises:

[0051] When the vehicle turns right, a first left field of view dividing line is generated by connecting the left camera and the left front corner point of the trailer compartment, and a first right field of view dividing line is generated by connecting the right front camera and the right rear corner point of the trailer compartment;

[0052] When the vehicle turns left, a second left field of view dividing line is generated by connecting the left camera and the left rear corner point of the trailer compartment, and a second right field of view dividing line is generated by connecting the right front camera and the right front corner point of the trailer compartment.

[0053] Specifically, the step 302 comprises: determining the right side of the first left field of view dividing line or the second left field of view dividing line as a first field of view blind area, and determining the left side of the first right field of view dividing line or the second right field of view dividing line as a second field of view blind area.

[0054] Specifically, the step 4 comprises:

[0055] When the vehicle turns right, a first auxiliary line and a second auxiliary line are drawn through the center point of the rear camera, the first auxiliary line is parallel to the first left field of view dividing line, and the second auxiliary line is parallel to the first right field of view dividing line, and the image between the first auxiliary line and the second auxiliary line in the rear camera image is determined as a right turn compensation image;

[0056] When the vehicle turns left, a third auxiliary line and a fourth auxiliary line are drawn through the center point of the rear camera, the third auxiliary line is parallel to the second left field-of-view boundary line, and the fourth auxiliary line is parallel to the second right field-of-view boundary line, and the image between the third auxiliary line and the fourth auxiliary line in the rear camera image is determined as a left-turn compensation image.

[0057] Specifically, the step 5 comprises: scaling the visible region image of the field of view of the left camera and the compensation image displayed on the left display screen of the electronic outside rearview mirror according to a first proportion K L scaling the visible region image of the field of view of the right camera and the compensation image displayed on the right display screen of the electronic outside rearview mirror according to a second proportion K R the first proportion and the second proportion are as follows:

[0058]

[0059]

[0060] wherein K L is the first proportion, K R is the second proportion, f1 is the focal length of the rear camera, f2 is the focal length of the left camera or the right camera, s is the distance of the corresponding pixel to the rear camera in the real world, l l is the vertical distance from the left camera to the rear edge of the trailer, and l r is the vertical distance from the right camera to the rear edge of the trailer.

[0061] The present application has the beneficial effects that: the present application establishes a kinematic model for the towing vehicle and the trailer, accurately calculates the track of the body of the towing vehicle and the trailer, respectively, and then uses the relative position relationship between the left and right cameras of the electronic outside rearview mirror and the rear camera at the rear of the trailer compartment to splice and process the rear field of view, so as to realize transparent display of the trailer compartment, thereby realizing monitoring of the field-of-view blind area and improving driving safety. BRIEF DESCRIPTION OF DRAWINGS

[0062] Figure 1 is a flowchart of the vehicle blind area monitoring method based on the electronic outside rearview mirror of the present application;

[0063] Figure 2 is a schematic diagram of the field-of-view regions of the left and right cameras of the present application;

[0064] Figure 3 is a schematic diagram of the body parameters of the present application;

[0065] Figure 4 is a schematic diagram of the global coordinate system of the present application. DETAILED DESCRIPTION

[0066] The embodiments of the present application will be described in detail below with reference to the accompanying drawings, which are used only for reference and illustration, and do not constitute a limitation on the scope of patent protection of the present application.

[0067] In the flow described in the specification, claims or drawings of the present application, the serial numbers of the respective steps (such as steps 10, 20, etc.) are only used to distinguish the respective steps, and the serial numbers themselves do not represent any execution order. It should be noted that the descriptions of "first", "second", etc. in this paper are only used to distinguish the description objects, and do not represent the order of precedence or the different types of "first", "second", etc.

[0068] As shown in Figure 1 , the embodiment provides a vehicle blind area monitoring method based on electronic outside rearview mirror, comprising:

[0069] Step 1, acquiring the current state parameters of the towing vehicle, including: the towing vehicle speed v, the steering wheel angle θ, the steering ratio k of the steering wheel and the front wheel of the towing vehicle, and the yaw angle φ1 of the towing vehicle.

[0070] Step 2, acquiring the pose of the towing vehicle at the previous time, and calculating the current position coordinates of the towing vehicle body angle point, left camera, right camera and rear camera according to the current state parameters.

[0071] In the specific implementation, as shown in Figure 2 , the left camera C L and the right camera C R of the electronic rearview mirror are respectively installed at the left front corner and the right front corner of the towing vehicle, and the rear camera C B is installed at the midpoint of the tail of the trailer, and the rear camera C B is a depth camera (RGB-D).

[0072] In the embodiment, the step 2 comprises:

[0073] Step 201, acquiring the body parameters of the towing vehicle and the trailer.

[0074] The body parameters of the towing vehicle and the trailer can be realized by measuring first and then inputting into the processing unit through the man-machine interaction system. As shown in Figure 3 , the body parameters that need to be measured include: the wheelbase L1 of the towing vehicle, the distance d between the hinge point and the center of the towing vehicle rear axle, the wheelbase L2 of the trailer, the steering ratio k of the steering wheel and the front wheel of the towing vehicle, the front suspension L 1f , the rear suspension L 1r and the vehicle width L 1b of the towing vehicle, and the front suspension L 2f , the rear suspension L 2r and the vehicle width L 2b of the trailer. The above body parameters correspond to the plan view as shown in Figure 4 .

[0075] It should be noted that when the hinge point is behind the center of the trailer rear axle, d is positive; when the hinge point is in front of the center of the trailer rear axle, d is negative.

[0076] Step 202, according to Ackerman kinematics, a kinematic model of the tractor and the trailer is established.

[0077] In this embodiment, a right-hand coordinate system is established as a global coordinate system with the position of the tractor at a certain motion moment (for example, the power-on moment) as the coordinate origin and the vehicle travel direction at the starting moment as the positive direction of the x-axis, as shown in Figure 4 .

[0078] Step 203, the pose of the tractor at the previous moment is obtained, and the pose of the tractor at the current moment is calculated according to a first preset relationship.

[0079] In this embodiment, the first preset relationship is:

[0080]

[0081] wherein, is the pose of the tractor at the current moment, is the pose of the tractor at the previous moment, v is the speed of the tractor, L1 is the wheelbase of the tractor, δ is the angle of the front wheel of the tractor, θ is the steering wheel angle, k is the steering ratio of the steering wheel and the front wheel of the tractor, and Δt is the sampling time interval.

[0082] Step 204, the motion state parameters of the hinge point at the current moment are determined, including the speed V P of the hinge point and the heading angle θ of the speed direction.

[0083] In this embodiment, the step 204 includes:

[0084] Step A1, the heading angle of the speed direction of the hinge point is determined according to a second preset relationship, and the second preset relationship is:

[0085]

[0086] wherein, θ is the heading angle of the speed direction of the hinge point, d is the distance between the hinge point and the center of the trailer rear axle, R1 is the turning radius of the tractor, L1 is the wheelbase of the tractor, and δ is the angle of the front wheel of the tractor.

[0087] Step A2, the speed of the hinge point is determined according to a third preset relationship, and the third preset relationship is:

[0088]

[0089] wherein, V Pis the speed of the hitch point, v is the speed of the towing vehicle, and θ is the heading angle of the speed direction of the hitch point.

[0090] Step A3, determining the position of the hitch point at the current time according to the pose of the towing vehicle at the current time through a fourth preset relationship, the fourth preset relationship being:

[0091]

[0092] wherein, is the pose of the towing vehicle at the current time, is the position of the towing vehicle at the current time, and d is the distance between the hitch point and the center of the rear axle of the towing vehicle.

[0093] Since the hitch point P of the towing vehicle and the trailer is the same point in the towing vehicle model and the trailer model, the speed direction and size of the hitch point P in the towing vehicle and the trailer are equal.

[0094] Step 205, determining the motion state parameters of the trailer at the current time according to the motion state parameters of the hitch point at the current time, including the speed of the center of the rear axle of the trailer, the rotational angular velocity of the trailer, the heading angle of the trailer at the current time , and the pose of the trailer at the current time.

[0095] In the embodiment, the step 205 includes:

[0096] Step B1, determining the speed of the center of the rear axle of the trailer according to a fifth preset relationship, the fifth preset relationship being:

[0097]

[0098] wherein, is the speed of the center of the rear axle of the trailer, V P is the speed of the hitch point, θ is the heading angle of the speed direction of the hitch point, and λ k-1 is the included angle between the heading of the towing vehicle and the heading of the trailer.

[0099] It is easy to understand that λ k-1 can be determined according to the following formula:

[0100]

[0101] Step B2, determining the rotational angular velocity of the trailer according to a sixth preset relationship, the sixth preset relationship being:

[0102]

[0103] wherein, ω2 is the rotational angular velocity of the trailer, and L2 is the wheelbase of the trailer.

[0104] Step B3, determining the heading angle of the trailer at the current time according to a seventh preset relationship, the seventh preset relationship being:

[0105]

[0106] wherein, is the heading angle of the trailer at the current time, is the sampling time interval of the system.

[0107] Step B4, determining the pose of the trailer at the current time according to an eighth preset relationship, the eighth preset relationship being:

[0108]

[0109] wherein, L2 is the wheelbase of the trailer.

[0110] In addition, the included angle λk between the towing vehicle and the trailer at the kth time k is:

[0111]

[0112] Step 206, determining the body corner point coordinates of the towing vehicle and the trailer according to the body parameters of the towing vehicle and the trailer, the pose of the towing vehicle at the current time, and the pose of the trailer at the current time.

[0113] In the embodiment, the step 206 includes:

[0114] determining the body corner point coordinates of the towing vehicle according to a ninth preset relationship, the ninth preset relationship being:

[0115]

[0116]

[0117]

[0118]

[0119] wherein, is the right front corner point of the towing vehicle, is the left front corner point of the towing vehicle, is the right rear corner point of the towing vehicle, is the left rear corner point of the towing vehicle.

[0120] determining the body corner point coordinates of the towing vehicle according to a tenth preset relationship, the tenth preset relationship being:

[0121]

[0122]

[0123]

[0124]

[0125] wherein, is a right front corner point of the trailer, is a left front corner point of the trailer, is a right rear corner point of the trailer, is a left rear corner point of the trailer.

[0126] Step 207, determining the current position coordinates of the left camera, the right camera and the rear camera according to the body corner point coordinates of the towing vehicle and the trailer.

[0127] In this embodiment, the step 207 comprises: determining the current position coordinates of the left camera, the right camera and the rear camera according to the following formula:

[0128]

[0129]

[0130]

[0131] wherein, is the current position coordinates of the left camera, is the current position coordinates of the right camera, is the current position coordinates of the rear camera.

[0132] Step 3, determining the visible area and the blind area of the field of view of the left camera and the right camera respectively according to the current position coordinates of the left camera, the right camera and the body corner points of the trailer.

[0133] In this embodiment, the step 3 comprises:

[0134] Step 301, determining the field of view dividing line of the left camera and the right camera according to the turning direction of the vehicle.

[0135] In this embodiment, the step 301 comprises:

[0136] When the vehicle turns right, a first left field of view dividing line L L1 is generated by connecting the left camera and the left front corner point of the trailer compartment, and a first right field of view dividing line L R1 is generated by connecting the right front camera and the right rear corner point of the trailer compartment;

[0137] When the vehicle turns left, a second left field of view dividing line L L2 is generated by connecting the left camera and the left rear corner point of the trailer compartment, and a second right field of view dividing line L is generated by connecting the right front camera and the right front corner point of the trailer compartment.R2 .

[0138] Figure 2 For the case of the vehicle turning right, the right side of the first left field boundary line L L1 , the left side of the first right field boundary line L R1 is determined as the first field blind area, and the right side of the second left field boundary line L L1 , the left side of the second right field boundary line L L2 is determined as the second field blind area.

[0139] Step 302, determining a field blind area according to the field boundary line.

[0140] In this embodiment, the step 302 includes: determining the right side of the first left field boundary line L L1 or the second left field boundary line L L2 as the first field blind area, and determining the left side of the first right field boundary line L R1 , the second right field boundary line L R2 as the second field blind area.

[0141] Step 4, cutting a corresponding compensation image from the rear camera image according to the turning direction of the vehicle and the field blind area.

[0142] In this embodiment, the step 4 includes:

[0143] When the vehicle turns right, draw a first auxiliary line L S1 , a second auxiliary line L S2 through the center point of the rear camera, the first auxiliary line L S1 is parallel to the first left field boundary line L L1 , and the second auxiliary line L S2 is parallel to the first right field boundary line L R1 , and the image between the first auxiliary line L S1 , the second auxiliary line L S2 in the rear camera image is determined as the right-turn compensation image.

[0144] When the vehicle turns left, draw a third auxiliary line L S3 , a fourth auxiliary line L S4 through the center point of the rear camera, the third auxiliary line L S3 is parallel to the second left field boundary line L L2 , and the fourth auxiliary line L S4 is parallel to the second right field boundary line L R2 , and the image between the third auxiliary line L S3 , the fourth auxiliary line L S4 in the rear camera image is determined as the left-turn compensation image.

[0145] Figure 2 For the case of the vehicle turning right, the first auxiliary line LS1 , the second auxiliary line L S2 schematic diagram, L S1 , L S2 The included angle θ formed in the field of view area of the rear camera is the right turn compensation image. The situation is similar when the vehicle turns right, the third auxiliary line L S3 , the fourth auxiliary line L S4 Not marked on the graph.

[0146] Step 5, scale the field of view visible area image of the left camera, the right camera, and the compensation image according to a preset ratio.

[0147] In this embodiment, the step 5 includes: scaling the field of view visible area image of the left camera and the compensation image displayed on the left display screen of the electronic outside rearview mirror according to a first ratio K L , and scaling the field of view visible area image of the right camera and the compensation image displayed on the right display screen of the electronic outside rearview mirror according to a second ratio K R , the first ratio K L , the second ratio K R is:

[0148]

[0149]

[0150] , the first ratio K L , the second ratio K R , f1 is the focal length of the rear camera, f2 is the focal length of the left camera or the right camera, s is the distance of the corresponding pixel to the rear camera in the real world, l l is the vertical distance from the left camera to the rear edge of the trailer, l r is the vertical distance from the right camera to the rear edge of the trailer.

[0151] Since the coordinates of the two left cameras and right cameras are respectively known , , the right rear corner point coordinate of the trailer is , the left rear corner point , the distance of the left camera to the straight line where the rear edge of the trailer is located , and the distance of the right camera to the straight line where the rear edge of the trailer is located .

[0152] Step 6, splice the scaled field of view visible area image of the left camera and the right camera and the compensation image according to a preset rule to generate a perspective image, and display the perspective image on the left and right display screens of the electronic outside rearview mirror.

[0153] In the embodiment, the step 6 comprises: splicing the zoomed left camera field of view visible region image on the left side of the zoomed compensation image, and splicing the zoomed right camera field of view visible region image on the right side of the zoomed compensation image.

[0154] The above disclosure is only the preferred embodiment of the present application, which cannot limit the protection scope of the present application, and the equivalent changes made in the patent application scope of the present application still belong to the scope covered by the present application.

Claims

1. A method of vehicle blind spot monitoring based on electronic outside mirrors, characterized in that, The method comprises the following steps: Step 1, acquiring current state parameters of the towing vehicle, including: vehicle speed, steering wheel angle, steering ratio of the steering wheel and the front wheel of the towing vehicle, yaw angle of the towing vehicle; Step 2, acquiring the pose of the towing vehicle at the previous time, and calculating the current position coordinates of the body corner points of the towing vehicle and the trailer, and the left camera, the right camera and the rear camera according to the current state parameters; Step 3, determining the visible area and the blind area of the field of view of the left camera and the right camera respectively according to the current position coordinates of the body corner points of the trailer and the left camera and the right camera; Step 4, according to the turning direction of the vehicle and the blind area of the field of view, the corresponding compensation image is cut from the rear camera image; Step 5, scaling the visible area images of the left camera and the right camera according to a preset proportion; Step 6, splicing the scaled visible area images of the left camera and the right camera and the compensation image according to a preset rule to generate a perspective image, and displaying the perspective image on the left and right display screens of the electronic outside rearview mirror; The step 2 comprises: Step 201, acquiring the body parameters of the towing vehicle and the trailer; Step 202, establishing a kinematic model of the towing vehicle and the trailer according to Ackermann kinematics; Step 203, acquiring the pose of the towing vehicle at the previous time, and calculating the pose of the towing vehicle at the current time according to a first preset relationship; Step 204, determining the motion state parameters of the articulation point at the current time, including the speed of the articulation point and the heading angle of the speed direction; Step 205, determining the motion state parameters of the trailer at the current time according to the motion state parameters of the articulation point at the current time, including the speed of the trailer rear axle center, the rotation angular velocity of the trailer, the heading angle of the trailer at the current time, and the pose of the trailer at the current time; Step 206, determining the body corner point coordinates of the towing vehicle and the trailer according to the body parameters of the towing vehicle and the trailer, the pose of the towing vehicle at the current time, and the pose of the trailer at the current time; Step 207, determining the current position coordinates of the left camera, the right camera and the rear camera according to the body corner point coordinates of the towing vehicle and the trailer; The first preset relationship is: wherein (x 1,k ,y 1,k ) is the body coordinate of the tractor at the current time, is the yaw angle of the tractor at the current time, is the body coordinate of the tractor at the previous time, is the yaw angle of the tractor at the previous time, v is the speed of the tractor, L1 is the wheelbase of the tractor, δ is the angle of the front wheel of the tractor, is the angle of the steering wheel, k is the steering ratio of the steering wheel and the front wheel of the tractor, and Δt is the sampling time interval.

2. The electronic exterior mirror-based vehicle blind spot monitoring method according to claim 1, characterized in that The step 204 comprises: Step A1, determining the heading angle of the speed direction of the articulation point according to a second preset relationship, the second preset relationship is: Wherein, θ is the heading angle of the speed direction of the articulation point, d is the distance between the articulation point and the towing vehicle rear axle center, R1 is the turning radius of the towing vehicle, L1 is the wheelbase of the towing vehicle, and δ is the angle of the front wheel of the towing vehicle; Step A2, determining the speed of the articulation point according to a third preset relationship, the third preset relationship is: where V P is the velocity of the articulation point, v is the velocity of the towing vehicle, and Θ is the heading angle of the direction of the articulation point velocity. Step A3, determining the current position of the articulation point at the current time through a fourth preset relationship according to the pose of the towing vehicle at the current time, the fourth preset relationship is: wherein (x p,k ,y p,k ) is the coordinate of the articulation point at the current time, is the pose of the towing vehicle at the current time, (x 1,k ,y 1,k ) is the position of the towing vehicle at the current time, and d is the distance between the articulation point and the center of the rear axle of the towing vehicle.

3. The electronic exterior mirror-based vehicle blind spot monitoring method according to claim 2, characterized in that The step 205 comprises: Step B1, determining the speed of the trailer rear axle center according to a fifth preset relationship, the fifth preset relationship is: v 2,k-1 = v p cos(λ k-1 -θ) where v 2,k-1 is the speed of the trailer rear axle center, V P is the speed of the hitch point, θ is the heading angle of the hitch point speed direction, λ k-1 is the angle between the towing vehicle heading and the trailer heading; Step B2, determining the rotation angular velocity of the trailer according to a sixth preset relationship, the sixth preset relationship is: Wherein, ω2 is the rotation angular velocity of the trailer, and L2 is the wheelbase of the trailer; Step B3, determining the heading angle of the trailer at the current time according to a seventh preset relationship, the seventh preset relationship being: wherein, is the current heading angle of the trailer; is the heading angle of the trailer at a previous time; Δt is the sampling time interval of the system; Step B4, determining the pose of the trailer at the current time according to an eighth preset relationship, the eighth preset relationship being: wherein L2 is the wheelbase of the trailer, (x 2,k ,y 2,k ) is the coordinate of the trailer at the current time.

4. The electronic exterior mirror-based vehicle blind spot monitoring method according to claim 3, characterized in that The step 3 comprises: Step 301, determining the field of view dividing line of the left camera and the right camera according to the turning direction of the vehicle; Step 302, determining the field of view blind area according to the field of view dividing line.

5. The electronic exterior mirror-based vehicle blind spot monitoring method according to claim 4, characterized in that The step 301 comprises: When the vehicle turns right, a first left field of view dividing line is generated by connecting the left camera and the left front corner point of the trailer compartment, and a first right field of view dividing line is generated by connecting the right front camera and the right rear corner point of the trailer compartment; When the vehicle turns left, a second left field of view dividing line is generated by connecting the left camera and the left rear corner point of the trailer compartment, and a second right field of view dividing line is generated by connecting the right front camera and the right front corner point of the trailer compartment.

6. The electronic- mirror-based vehicle blind spot monitoring method according to claim 5, characterized in that The step 302 comprises: determining the right side of the first left field of view dividing line or the second left field of view dividing line as a first field of view blind area, and determining the left side of the first right field of view dividing line or the second right field of view dividing line as a second field of view blind area.

7. The electronic- mirror-based vehicle blind spot monitoring method according to claim 6, characterized in that The step 4 comprises: When the vehicle turns right, a first auxiliary line and a second auxiliary line are drawn through the center point of the rear camera, the first auxiliary line is parallel to the first left field of view dividing line, the second auxiliary line is parallel to the first right field of view dividing line, and the image between the first auxiliary line and the second auxiliary line in the rear camera image is determined as a right-turn compensation image; When the vehicle turns left, a third auxiliary line and a fourth auxiliary line are drawn through the center point of the rear camera, the third auxiliary line is parallel to the second left field of view dividing line, the fourth auxiliary line is parallel to the second right field of view dividing line, and the image between the third auxiliary line and the fourth auxiliary line in the rear camera image is determined as a left-turn compensation image.

8. The electronic- mirror-based vehicle blind spot monitoring method according to claim 7, characterized in that The step 5 comprises: scaling the field of view visible area image, the compensation image of the left camera displayed on the left display screen of the electronic outside rearview mirror according to a first proportion K L scaling the field of view visible area image, the compensation image of the right camera displayed on the right display screen of the electronic outside rearview mirror according to a second proportion K R The first proportion and the second proportion are: wherein K L is a first proportionality, K R is a second proportionality, f1 is the focal length of the rear camera, f2 is the focal length of the left or right camera, s is the distance of the corresponding pixel in the real world from the rear camera, l l is the vertical distance of the left camera to the rear edge of the trailer, and l r is the vertical distance of the right camera to the rear edge of the trailer.

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