Millimeter wave radar angle measurement compensation method based on commercial vehicle

Abstract

The invention discloses a millimeter wave radar angle measurement compensation method based on a commercial vehicle. The method comprises the steps of obtaining a static point cloud of a static fence on the front side of the commercial vehicle; performing polynomial fitting on fence points in the longitudinal range of + / -10m of the commercial vehicle to obtain a first fitting straight line, and calculating an inclined included angle theta S between the first fitting straight line and the side surface of the vehicle body; fitting the fence points in the 10m longitudinal range of the nth section to obtain a second fitting straight line, and obtaining an inclined included angle theta n between the second fitting straight line and the side surface of the vehicle body; for the 10m longitudinal range of the nth section, calculating a compensation angle theta n; according to the motion trail of the detected target, determining the i-th segment to which the detected target belongs; and calculating a real included angle theta C according to the detection included angle theta measured by the millimeter wave radar and the compensation angle theta i of the ith section. The millimeter wave radar angle measurement compensation method based on the commercial vehicle has the advantages that the accuracy of side radar detection and normal triggering of functions can be guaranteed, and the probability of false alarm and missing alarm is reduced.

Description

Technical Field

[0001] The present invention relates to a vehicle radar angle measurement compensation technology, in particular to a millimeter wave radar angle measurement compensation method based on a commercial vehicle. Background Art

[0002] With the rapid development of automotive technology, the level of intelligence in cars is becoming increasingly higher. Currently, autonomous driving can be divided into six levels, from L0 to L5: L0 is a fully manually driven vehicle. Although it may have auxiliary protection systems such as brake assist and blind spot monitoring, the driver must remain in full control throughout the entire process. L1 is an assisted driving level that can assist the driver in completing simple repetitive operations such as adaptive cruise control speed and lane keeping assist control direction. The driver still participates in the entire process. L2 is a partially automated vehicle that can control speed and direction simultaneously, such as adaptive cruise control with lane keeping, automatic parking, and automatic lane change, but the driver must monitor the environment and take over at any time. L3 is conditional autonomous driving. Under limited conditions, the driver can give up control, but system problems require the driver to take over for a short period of time. L4 is highly automated driving that can complete driving tasks and monitor the environment under specific circumstances and conditions without driver intervention. L5 is fully automated and can complete all driving tasks under any conditions.

[0003] Millimeter-wave radar operates in the millimeter wave band. Millimeter waves typically range from 30 to 300 GHz (with a wavelength of 1 to 10 mm). Millimeter-wave wavelengths lie between microwaves and centimeter waves, so millimeter-wave radar combines the advantages of both microwave and photoelectric radar. Millimeter-wave radar is widely used due to its all-day, all-weather operation, long range, and high velocity measurement accuracy.

[0004] In recent years, with the rapid development of autonomous driving technology, 77GHz millimeter-wave radar has been increasingly used in automotive driver assistance systems due to its wide bandwidth, high detection accuracy, and all-weather operation. Commercial vehicles (generally referring to trailers or dump trucks) have long bodies, large turning radii, or are overloaded with cargo, which increases the driver's blind spot. When changing lanes or turning, it is easy to overlook small objects such as children, bicycles, or electric scooters. This has led to the development of side radars. Side radars are typically installed on the side of the vehicle to monitor the surrounding environment and obstacles, particularly the blind spots and close-range obstacles on the side of the vehicle.

[0005] To increase radar's detection range, side radar systems often consist of two radars arranged in a triangle or trapezoidal configuration and installed at the rear of a commercial vehicle's front or near the fuel tank to address the driver's blind spot. However, due to the length of trailer trucks, often exceeding 10 meters, and the numerous metal reflective surfaces, multipath reflections can affect the radar's angular performance. For example, on urban roads or highways, the angle of the detected target behind a large truck will shift toward the vehicle. This shift increases with distance, often by as much as a lane, impacting the truck's functional judgment. Summary of the Invention

[0006] In order to avoid the shortcomings of the above-mentioned existing technologies, the present invention provides a millimeter-wave radar angle measurement compensation method based on commercial vehicles to ensure the accuracy of side radar detection and the normal triggering of functions, and reduce the probability of false alarms and missed alarms.

[0007] The present invention adopts the following technical solutions to solve the technical problems.

[0008] The present invention provides a millimeter-wave radar angle measurement compensation method for commercial vehicles, comprising the following steps:

[0009] Step S1: Obtain a stationary point cloud of the stationary fence on the front side of the commercial vehicle; determine the fence points in the stationary point cloud; perform polynomial fitting on the fence points within the longitudinal range of ±10 meters of the commercial vehicle to obtain a first fitting line, and calculate the inclination angle θ between the first fitting line and the side of the vehicle body S ;

[0010] Step S2: Count and judge the number of fence points N within a longitudinal range of 10 meters at every 10 meters from the side and rear of the commercial vehicle; if the number of fence points M within a longitudinal range of 10 meters in the nth segment is n If the number is not less than the preset value M0, the fence points within the longitudinal range of 10 meters in the nth segment are fitted to obtain a second fitting straight line, and the inclination angle θ between the second fitting straight line and the side of the vehicle body is obtained. n ; The tilt angle of the nth segment is recorded as θ n ;

[0011] Step S3: For the 10-meter longitudinal range of the nth segment, calculate the compensation angle Δθ n ;

[0012] Step S4: Determine the i-th segment to which the detected target belongs based on the motion trajectory of the detected target; and determine the detection angle θ obtained by millimeter-wave radar measurement and the compensation angle Δθ of the i-th segment. i Calculated true angle θ C .

[0013] The millimeter-wave radar angle measurement compensation method based on a commercial vehicle of the present invention is also characterized in that:

[0014] Furthermore, in step S1, when determining the longitudinal range of ±10 meters of the commercial vehicle, the connection between the front of the vehicle and the vehicle body is determined as the zero point.

[0015] Furthermore, in the above step S3, the compensation angle Δθ n The calculation formula is shown in the following formula (1);

[0016] Δθ n =θ n -θ S (1)

[0017] In formula (1), θ S is the inclination angle between the first fitting line and the side of the vehicle body, θ n It is the inclination angle between the second fitting straight line in the nth 10-meter range at the rear side of the commercial vehicle and the side surface of the vehicle body.

[0018] Furthermore, in the above step S4, the compensation angle Δθ n The calculation of is shown in the following formula (2);

[0019] θ C =θ+Δθ n (2)

[0020] Where θ is the detection angle value detected by the vehicle radar.

[0021] The present invention also discloses an electronic device, comprising at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0022] The present invention also discloses a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to execute the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0023] The present invention also discloses a computer program product, comprising a computer program; when the computer program is executed by a processor, the computer program implements the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0024] Compared with the existing technology, the beneficial effects of the present invention are embodied in:

[0025] The present invention discloses a millimeter-wave radar angle measurement compensation method based on a commercial vehicle, comprising: obtaining a stationary point cloud of a stationary fence on the front side of the commercial vehicle; performing polynomial fitting on the fence points within a range of ±10 meters in the longitudinal direction of the commercial vehicle to obtain a first fitting straight line; and calculating the tilt angle θ between the first fitting straight line and the side of the vehicle body. S ; Fit the fence points within the 10-meter longitudinal range of the nth segment to obtain a second fitting straight line, and obtain the inclination angle θ between the second fitting straight line and the side of the vehicle body n For the 10-meter longitudinal range of the nth segment, calculate the compensation angle △θ n ; According to the motion trajectory of the detected target, determine the i-th segment to which the detected target belongs; according to the detection angle θ measured by the millimeter wave radar and the compensation angle △θ of the i-th segment i Calculated true angle θ C .

[0026] The millimeter-wave radar angle measurement compensation method based on commercial vehicles of the present invention has the advantages of ensuring the accuracy of side radar detection and normal triggering of functions, reducing the probability of false alarms and missed alarms, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a flow chart of a millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to the present invention.

[0028] Figure 2 This is a state diagram of radar detecting a target before the angle compensation according to the present invention is adopted.

[0029] Figure 3 The figure is a radar target detection state diagram after adopting the millimeter-wave radar angle measurement compensation method based on a commercial vehicle of the present invention.

[0030] Figure 4 This is a schematic diagram of various parameters of a millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to the present invention.

[0031] The present invention will be further described below through specific implementation methods in conjunction with the accompanying drawings. DETAILED DESCRIPTION

[0032] See also Figures 1 to 3 The present invention provides a millimeter-wave radar angle measurement compensation method for commercial vehicles, comprising the following steps:

[0033] Step S1: Obtain a stationary point cloud of the stationary fence on the front side of the commercial vehicle; determine the fence points in the stationary point cloud; perform polynomial fitting on the fence points within the longitudinal range of ±10 meters of the commercial vehicle to obtain a first fitting line, and calculate the inclination angle θ between the first fitting line and the side of the vehicle body S ;

[0034] In practice, the features of the static point clouds on the side can be simply judged. For example, the arrangement of the static point clouds can be used to determine if a continuous static object exists when the static point clouds are densely packed into a straight line.

[0035] In addition, the existing technology can also be used to determine the fence points. For example, the method of the invention patent with application number "CN202311422065.0" and patent name "Roadside Identification Method, Device, Storage Medium and Electronic Device" is used to determine the fence points. The method includes: obtaining the static point trace distribution information of the target frame; dividing the multiple static point traces into each horizontal group according to the horizontal position distribution information of the multiple static point traces, and obtaining a first statistical result of the horizontal histogram; determining the target horizontal group with the most concentrated static point traces from the first statistical result; dividing the static point traces in the target horizontal group into each vertical group according to the vertical position distribution information of the static point traces in the target horizontal group, and obtaining a second statistical result of the vertical histogram; calculating the degree of dispersion based on the second statistical result to obtain the target discrete value between each vertical group, and determining the target roadside identification result of the target frame based on the target discrete value. The specific judgment process is described in the patent.

[0036] Step S2: Count and judge the number of fence points N within a longitudinal range of 10 meters at every 10 meters from the side and rear of the commercial vehicle; if the number of fence points M within a longitudinal range of 10 meters in the nth segment is n If the number is not less than the preset value M0, the fence points within the longitudinal range of 10 meters in the nth segment are fitted to obtain a second fitting straight line, and the inclination angle θ between the second fitting straight line and the side of the vehicle body is obtained. n ; The tilt angle of the nth segment is recorded as θ n ;

[0037] Step S3: For the 10-meter longitudinal range of the nth segment, calculate the compensation angle Δθ n ;

[0038] Step S4: Determine the i-th segment to which the detected target belongs based on the motion trajectory of the detected target; and determine the detection angle θ obtained by millimeter-wave radar measurement and the compensation angle Δθ of the i-th segment. i Calculated true angle θ C .

[0039] The present invention's millimeter-wave radar angle compensation method for commercial vehicles provides different compensation angles Δθ for angle measurement based on the detected target at different distances behind the commercial vehicle. This addresses the situation where the detected target's position deviates from its true position by different values (maximum deviation of one lane) at different distances, ensuring detection accuracy and proper function triggering, while reducing the probability of false alarms and missed alarms. By performing angle compensation on the detected target behind a large truck, the present invention restores the detected target to its true position, reduces the target's deviation due to distance, and ensures the safe operation of the large truck.

[0040] In specific implementation, in step S1, when determining the longitudinal range of ±10 meters of the commercial vehicle, the connection between the front of the vehicle and the vehicle body is determined as the zero point.

[0041] In step 1, the number of stationary point clouds on the front side of the truck is first counted to determine whether they are fence points. Based on the judgment result, a polynomial fitting is performed on the fence points whose zero point of the vehicle body is within the longitudinal range of ±10 meters to obtain a first fitting line. Based on the result of the polynomial fitting, the inclination angle θ between the first fitting line and the vehicle body is obtained. S , and use it as the standard value.

[0042] like Figure 2 and Figure 3 , set the connection between the front and the carriage as the zero point. The forward direction of the truck or the direction of the front of the truck is a square, the front of the zero point is positive, and the back of the zero point is negative.

[0043] The result of judging the fence point is that there is a fence on the side. This is because the fence points within 10 meters in front and behind the side of the vehicle are relatively straight; Figure 2 and Figure 3 The red circles on the right are stationary fence points. These red circles are used to perform quadratic fitting to form the first fitting line. The first fitting line is not necessarily completely parallel to the vehicle body, but there will be a certain angle between them. This angle is used as the basic standard θ S , in preparation for subsequent compensation.

[0044] In the specific implementation, in the above step S3, the compensation angle Δθ n The calculation formula is shown in the following formula (1);

[0045] Δθ n =θ n -θ S (1)

[0046] In formula (1), θ S is the inclination angle between the first fitting line and the side of the vehicle body, θ n It is the inclination angle between the second fitting straight line in the nth 10-meter range at the rear side of the commercial vehicle and the side surface of the vehicle body.

[0047] In the specific implementation, in the above step S4, the compensation angle Δθ n The calculation of is shown in the following formula (2);

[0048] θ C =θ+Δθ n (2)

[0049] Where θ is the detection angle value detected by the vehicle radar.

[0050] The present invention also discloses an electronic device, comprising at least one processor and a memory communicatively connected to the at least one processor; the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0051] The present invention also discloses a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to execute the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0052] The present invention also discloses a computer program product, comprising a computer program; when the computer program is executed by a processor, the computer program implements the commercial vehicle-based millimeter-wave radar angle measurement compensation method.

[0053] In the present invention, the number M of fence points within the longitudinal range of 10 meters every 10 meters outside the side and rear of the zero point is statistically determined. A preset value M0 is set. If the number M of fence points reaches the preset value M0, that is, M n ≥M0, the fence points are fitted to obtain a second fitting line, and the tilt angle θ between the second fitting line and the vehicle body is calculated. The number of fence points M does not reach the preset value M0, that is, M n When < M0, fence fitting is not performed. In specific implementation, M0 is generally obtained based on a large number of statistics to obtain a statistical value that mostly meets the conditions.

[0054] like Figure 2 and Figure 3 After the fence point is judged and fitted, the curved part 10 meters outside the fence (10 meters outside the longitudinal direction) can be fitted (see the following Figure 2 A quadratic fitting is performed for the fence points on the right side of the vehicle. Specifically, a quadratic fitting is performed for each fence point within a 10-meter range. After each fitting, an inclined second fitting straight line is obtained. The angle between the second fitting straight line of the 10-meter longitudinal range of the nth segment and the vehicle body is recorded as θ. nThen the second fitting straight line will form an angle with the first fitting straight line, which is Δθ n ; That is: Δθ n =θ n -θ S .

[0055] In the present invention, within the longitudinal range of ±10 meters on the side of the commercial vehicle, the fence points within the range are fitted to obtain a first fitting straight line, and the angle between the first fitting straight line and the vehicle body is taken as the standard value θ S .

[0056] Based on the fitting angle of the fence point on the front side of the vehicle, the distance 10 meters behind the vehicle is divided into 10-meter segments. The total number of segments is N. The tilt angle of the nth segment in N segments is recorded as θ n Therefore, according to formula (1), N compensation angles Δθ can be obtained. The N compensation angles Δθ are listed as a series of compensation angles, Δθ = [Δθ1, Δθ2, ... Δθ n ...Δθ N ].

[0057] By extracting corresponding compensation in different distance segments to compensate for the detection angle error of the detected target, the detected target can be restored to the correct position in the radar coordinate system, ensuring the correct triggering of the radar function.

[0058] In the present invention, the distance range of the detected target is first determined based on the motion trajectory of the detected target. Figure 2 and Figure 3 In the figure, the blue solid points are the detected targets, and the red hollow circles are the fence points. Figure 2 and Figure 3 , the connection between the front and the carriage is set as zero point O, the center line of the lane where the vehicle body is located is also the zero point line, the vehicle's forward direction or the direction of the front is the longitudinal direction, and the coordinate system is established as follows Figure 2 As shown. The coordinates in front of the zero point and behind the zero point are positive and negative respectively. In the present invention, the detection angle θ of the detected target is compensated according to the distance between the detected target and the zero point O in the longitudinal direction, and the compensated angle θ is calculated. C .

[0059] For example, when the blue detected target moves between -30 and -40 meters, the angle value of Δθ3 is compensated; when it moves between -20 and -30 meters, the value of Δθ2 is compensated. When specifically compensating, the following formula (2) is used to compensate the detection angle θ of the detected target.

[0060] θ C =θ+Δθ n (2)

[0061] Where θ is the detection angle value detected by the vehicle radar.

[0062] In such Figure 2 and Figure 3 In the coordinate system of the vehicle, the coordinate value of the detected target is calculated according to the following formula (3), and the detected target is restored to its real position in the vehicle coordinate system.

[0063] X=R*sin(θ c )

[0064] Y=R*cos(θ C ) (3)

[0065] Where (X, Y) is the coordinate value of the detected target in the coordinate system shown; R is the distance between the detected target and the zero point O determined by the vehicle body, as shown in Figure 2 shown.

[0066] like Figure 2 , is the position of the detected target without compensation when the truck is driving normally, and the state of the surrounding fence in the vehicle coordinate system. Figure 2 As can be seen in the figure, due to the length of the truck, all targets 25 meters behind the vehicle are offset toward the vehicle, and the offset increases with distance. Targets in the adjacent lane behind the vehicle are offset behind the vehicle, which can cause false alarms in the radar and lead to unstable driving safety.

[0067] Figure 3 This is the effect diagram after angle compensation. Figure 3 It can be seen that after compensation, all targets are restored to near their actual positions, which effectively makes up for the defect that the long truck body has a certain impact on radar detection.

[0068] like Figure 4 It is a schematic diagram of the various parameters of the above formula (1), formula (2) and formula (2).

[0069] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0070] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A millimeter wave radar angle measurement compensation method based on commercial vehicles, characterized in that: The steps include: Step S1: Obtain a stationary point cloud of the stationary fence on the front side of the commercial vehicle; determine the fence points in the stationary point cloud; perform polynomial fitting on the fence points within the longitudinal range of ±10 meters of the commercial vehicle to obtain a first fitting line, and calculate the inclination angle θ between the first fitting line and the side of the vehicle body S ; Step S2: Count and judge the number of fence points N within a longitudinal range of 10 meters at every 10 meters from the side and rear of the commercial vehicle; if the number of fence points M within a longitudinal range of 10 meters in the nth segment is n If the number is not less than the preset value M0, the fence points within the longitudinal range of 10 meters in the nth segment are fitted to obtain a second fitting straight line, and the inclination angle θ between the second fitting straight line and the side of the vehicle body is obtained. n ; The tilt angle of the nth segment is recorded as θ n ; Step S3: For the 10-meter longitudinal range of the nth segment, calculate the compensation angle Δθ n ; Step S4: Determine the i-th segment to which the detected target belongs based on the motion trajectory of the detected target; and determine the detection angle θ obtained by millimeter-wave radar measurement and the compensation angle Δθ of the i-th segment. i Calculated true angle θ C .

2. The millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to claim 1 is characterized in that: In step S1, when determining the longitudinal range of ±10 meters of the commercial vehicle, the connection between the front of the vehicle and the vehicle body is determined as the zero point.

3. The millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to claim 2, characterized in that: In the above step S3, the compensation angle Δθ n The calculation formula is shown in the following formula (1); Dth n =θ n -θ S (1) In formula (1), θ S is the inclination angle between the first fitting line and the side of the vehicle body, θ n It is the inclination angle between the second fitting straight line in the nth 10-meter range at the rear side of the commercial vehicle and the side surface of the vehicle body.

4. The millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to claim 2, characterized in that: In the above step S4, the compensation angle Δθ n The calculation of is shown in the following formula (2); i C =θ+Δθ n (2) Where θ is the detection angle value detected by the vehicle radar.

5. An electronic device comprising at least one processor and a memory communicatively connected to the at least one processor; wherein: The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the commercial vehicle-based millimeter-wave radar angle measurement compensation method according to any one of claims 1 to 4.

6. A non-transitory computer-readable storage medium storing computer instructions, characterized in that: The computer instructions are used to enable the computer to execute the millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to any one of claims 1 to 4.

7. A computer program product comprising a computer program; wherein: When the computer program is executed by a processor, the computer program implements the millimeter-wave radar angle measurement compensation method based on a commercial vehicle according to any one of claims 1 to 4.

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