Millimeter-wave radar system for two-wheelers with human perception and rear warning functions

Abstract

The present invention discloses a two-wheeled vehicle millimeter wave radar system with human perception and rear warning functions, which belongs to the field of millimeter wave radar technology, and includes a millimeter wave radar device that can adjust the detection direction to forward toward the driver and backward toward the driver; a direction acquisition module, which acquires the direction state of the millimeter wave radar device; a mode judgment module, which judges whether the millimeter wave radar device enters a personnel perception mode or a rear warning mode according to the direction state of the millimeter wave radar device, and outputs the mode judgment result to a control module; a control module, which controls the millimeter wave radar device to enter a personnel perception mode or a rear warning mode according to the mode judgment result. In the above manner, the present invention can automatically realize the driver's human presence perception or rearward vehicle warning of a two-wheeled vehicle by adjusting the detection direction of the millimeter wave radar device to forward toward the driver and backward toward the driver, thereby providing users with two safety detection functions.

Description

Technical Field

[0001] The invention relates to the technical field of millimeter wave radars, and in particular to a two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions. Background Art

[0002] Electric two-wheeled vehicles include electric vehicles and electric assisted vehicles. As the popularity of electric two-wheeled vehicles increases, and there are fewer safety products related to two-wheeled vehicles, drivers have a strong demand for safety features such as human perception and rear warning.

[0003] Millimeter-wave radar is a commonly used sensor for human detection. It can detect the presence of a human body or an object in space, and is used to assist in security and personnel perception scenarios.

[0004] However, millimeter wave radars are rarely used on two-wheeled vehicles. At the same time, the existing technology cannot use a millimeter wave radar to simultaneously realize the functions of human perception and rear vehicle warning for two-wheeled vehicles.

[0005] Based on this, the present invention designs a two-wheeled vehicle millimeter wave radar system with human perception and rear warning functions and a corresponding detection method to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A millimeter-wave radar system for a two-wheeled vehicle with human perception and rear warning functions, comprising a millimeter-wave radar device capable of adjusting the detection direction to face forward toward a driver and face backward toward the driver;

[0009] A direction acquisition module, which acquires the direction status of the millimeter wave radar device;

[0010] A mode judgment module, which judges whether the millimeter-wave radar device enters a personnel perception mode or a rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module;

[0011] A control module controls the millimeter wave radar device to enter a personnel sensing mode or a backward warning mode according to a mode judgment result;

[0012] When the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode, the millimeter-wave radar device loads the configuration parameters of the personnel perception mode, periodically performs radar detection, and outputs the detection results;

[0013] When the detection direction of the millimeter-wave radar device is backward from the driver, the rear warning mode is executed, the configuration parameters of the rear warning mode are loaded, the radar detection is performed periodically, and the detection results are output.

[0014] Furthermore, the millimeter-wave radar device adopts a vertically flip-type millimeter-wave radar device or a horizontally flip-type millimeter-wave radar device.

[0015] Furthermore, in the personnel perception mode, the process steps of each detection cycle of the millimeter-wave radar device are as follows:

[0016] 1.1) The millimeter-wave radar device sends a frequency-modulated continuous pulse signal through one TX antenna, receives the reflected echo signal of the target through two radar receiving antennas RX, mixes and demodulates the echo signal to obtain two-channel ADC data, and caches the data.

[0017] 1.2) Perform a fast frame operation, perform 1D-FFT processing on the two-channel ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension, and remove the information with a Doppler velocity of 0; perform CFAR and angle estimation on the FFT results obtained twice to obtain the target point cloud data of the moving points.

[0018] 1.3) Determine whether the number of cached data frames reaches 32. If not, directly proceed to the next step. If so, perform a slow frame operation. After averaging the 32-frame ADC data in the cache, perform 1D-FFT and 2D-FFT processing, and through CFAR and angle estimation, obtain the target point cloud of the static points, and release the cached data.

[0019] 1.4) Perform density-based clustering methods on the target point cloud data of the moving points and the static points respectively, output the moving target data and the static target data, and perform α-β filtering processing on the data.

[0020] 1.5) Output the obtained target tracks to the functional layer for screening and position judgment of the target data.

[0021] Furthermore, in step 1.5), the implementation steps of the functional layer include:

[0022] One: Preprocess the target data and剔除 the invalid targets: 0 <= range <= range_max, -60° < angle < 60°. When there is no target, output the unmanned state. When there is a target, perform the next operation.

[0023] Two: Calculate the target coordinate points (x, y) for the valid targets:

[0024] x = range * sin(angle);

[0025] y = range * cos(angle);

[0026] Obtain the position point (x, y) of the target;

[0027] III: Based on the coordinate values of all targets, determine whether there is a target in the driving area, where x_valid_min1 < x < x_valid_max1 and 0 < y < y_valid_max1. Here, x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis. If there is no target in the driving area, record it as the driver being out of the vehicle state; if there is a target in the driving area, record it as the driver getting into the vehicle state;

[0028] IV: Output the personnel monitoring result.

[0029] Furthermore, in the rear warning mode, the process steps of the millimeter-wave radar device for each detection cycle are as follows:

[0030] 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through one TX antenna, and receives the reflected echo signals of the target through 2 radar receiving antennas RX. Mix and demodulate the echo signals to obtain two-channel ADC data.

[0031] 2.2) Perform 1D-FFT processing on the two-channel ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension. Perform CFAR and angle estimation on the FFT results obtained twice, and use the different ambiguous speeds generated by the two waveforms to perform speed ambiguity resolution to obtain the point cloud data of the target;

[0032] 2.3) Perform a density-based clustering method based on the point cloud data to output the target data, including the azimuth angle, distance, and speed of the target, and perform EKF filtering processing on the target data to achieve target tracking, and input the result into the functional layer;

[0033] 2.4) The functional layer calculates based on the speed and azimuth of the target, determines whether there is a target that meets the alarm condition, and outputs the result.

[0034] Furthermore, in step 2.4), the implementation steps of the functional layer include:

[0035] I: Preprocess the target data, screen out the targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and剔除 the invalid targets;

[0036] II: Calculate the target coordinate points (x, y) for the valid target:

[0037] x = range * sin(angle);

[0038] y = range * cos(angle);

[0039] Obtain the position points (x, y) of the target;

[0040] III: Determine whether the target is within the alarm area based on the coordinate values of the target, x_valid_min < x < x_valid_max, where x_valid_min represents the minimum value within the alarm area on the X-axis, and x_valid_max represents the maximum value within the alarm area on the X-axis;

[0041] If the target is not within the alarm area, eliminate the target. At the same time, establish the speed constraint of the target. When the relative speed of the target is negative, eliminate the target. If the relative speed of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and speed; where TTC represents the possible collision time of the target, range represents the distance of the target relative to the radar, and vel represents the relative speed of the target to the radar.

[0042] IV: When there is a situation where TTC < 3s for all remaining targets, an alarm needs to be issued and the alarm area needs to be determined. The alarm area is divided into two parts, the left and the right. Determine whether it is the left area or the right area according to the sign of the x value;

[0043] V: Output the detection results of this cycle.

[0044] Furthermore, the vertical flip type millimeter wave radar device includes a radar module 1 and a mounting bracket A2. Both ends of the radar module 1 are respectively fixedly connected with a flip shaft 22, and the two flip shafts 22 are respectively rotationally connected with both ends of the mounting bracket A2; wire grooves 21 are respectively opened at the upper parts of both ends of the mounting bracket A2, and a plurality of mounting holes A23 are opened at the bottom of the mounting bracket A2. The mounting bracket A2 is fixedly connected with a two-wheeled vehicle through the mounting holes A23.

[0045] Furthermore, the horizontal flip type millimeter wave radar device includes a radar module 1 and a mounting bracket B3. The bottom of the radar module 1 is rotationally connected with the mounting bracket B3 through a flip shaft, and a plurality of mounting holes B32 are opened on the mounting bracket B3. The mounting bracket B3 is fixedly connected with a two-wheeled vehicle through the mounting holes B32.

[0046] Furthermore, the bottom of the radar module 1 is fixedly connected with a flip shaft 31, and the bottom of the flip shaft 31 is rotationally connected with the mounting bracket B3.

[0047] The present invention also discloses a detection method of a two-wheeled vehicle millimeter wave radar system with human body perception and backward warning functions, comprising the following steps:

[0048] S1. Adjust the detection direction by rotating the millimeter wave radar device to face the driver or face away from the driver;

[0049] S2, the orientation acquisition module acquires the orientation state of the millimeter wave radar device;

[0050] S3, the mode judgment module judges whether the millimeter-wave radar device enters the personnel perception mode or the rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module;

[0051] S4, the control module controls the millimeter wave radar device to enter the personnel perception mode or the backward warning mode according to the mode judgment result;

[0052] A. When the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode. The millimeter-wave radar device loads the configuration parameters of the personnel perception mode and performs radar detection periodically. The process steps of each detection cycle are:

[0053] 1.1) The millimeter wave radar device sends a frequency modulated continuous pulse signal through a TX antenna, and receives the reflected echo signal of the target through two radar receiving antennas RX, mixes and demodulates the echo signal to obtain two ADC (analog-to-digital converter) data, and caches the data;

[0054] 1.2) Perform fast frame operation, perform 1D-FFT (one-dimensional Fourier transform) processing on the two ADC data to obtain the spectrum of the distance dimension, and perform 2D-FFT (two-dimensional fast Fourier transform) processing based on the result to obtain the spectrum of the Doppler dimension, and remove the information of Doppler velocity of 0; perform CFAR (constant false alarm rate) and angle estimation on the FFT (fast Fourier transform) results obtained twice to obtain the target point cloud data of the moving point;

[0055] 1.3) Determine whether the number of cached data frames reaches 32 frames. If not, proceed directly to the next step. If yes, perform slow frame operation. The cached 32 frames of ADC data are averaged, and then 1D-FFT and 2D-FFT are processed. Through CFAR and angle estimation, the target point cloud of the static point is obtained, and the cached data is released;

[0056] 1.4) Perform density-based clustering methods on the target point cloud data of the moving point and the target point cloud of the static point, output the moving target data and the static target data, and perform α-β filtering on the data;

[0057] 1.5) Output the obtained target traces to the functional layer, and the functional layer performs the following steps:

[0058] Preprocess the target data and eliminate invalid targets: 0 <= range (distance) <= range_max (the maximum detection distance of the radar), -60° < angle < 60°. When there are no targets, output the unmanned state, and when there are targets, perform the next operation;

[0059] Calculate the target coordinate points (x, y) for valid targets:

[0060] x = range * sin(angle);

[0061] y = range * cos(angle);

[0062] Obtain the position points (x, y) of the target;

[0063] Based on the coordinate values of all targets, determine whether there are targets in the driving area, x_valid_min1 < x < x_valid_max1, 0 < y < y_valid_max1, where x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis; if there are no targets in the driving area, record it as the driver away from the vehicle state, and if there are targets in the driving area, record it as the driver entering the vehicle state;

[0064] Output the personnel monitoring result to achieve personnel perception;

[0065] B. When the detection direction of the millimeter-wave radar device is backward from the driver, execute the rear warning mode, load the configuration parameters of the rear warning mode, and perform radar detection periodically. The process steps of each detection cycle are as follows:

[0066] 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through one TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. Mix and demodulate the echo signals to obtain two channels of ADC data;

[0067] 2.2) Perform 1D-FFT processing on the two channels of ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the results to obtain the spectrum in the Doppler dimension; perform CFAR and angle estimation on the FFT results obtained twice, and use the different ambiguous speeds generated by the two waveforms to perform speed deblurring to obtain the point cloud data of the target;

[0068] 2.3) Based on the point cloud data, perform a density-based clustering method to output the target data, including the azimuth angle, distance, and speed of the target, and perform EKF (Extended Kalman Filter) filtering on the target data to achieve target tracking, and input the results into the functional layer;

[0069] 2.4) The functional layer performs the following steps:

[0070] Preprocess the target data to screen out the targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and剔除 the invalid targets;

[0071] Calculate the target coordinate points (x, y) for the valid targets:

[0072] x = range * sin(angle);

[0073] y = range * cos(angle);

[0074] Obtain the position points (x, y) of the target;

[0075] Based on the coordinate values of the target, determine whether it is in the alarm area, x_valid_min < x < x_valid_max, where x_valid_min represents the minimum value in the alarm area on the X-axis, and x_valid_max represents the maximum value in the alarm area on the X-axis;

[0076] If it is not in the alarm area,剔除 the target, and at the same time establish the speed constraint of the target. When the relative speed of the target is negative,剔除 the target. If the relative speed of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and speed; where TTC represents the possible collision time of the target, range represents the distance of the target relative to the radar, and vel represents the relative speed of the target to the radar;

[0077] When all the remaining targets have TTC < 3s, an alarm needs to be issued and the alarm area needs to be judged. The alarm area is divided into two parts, left and right. Judge whether it is the left area or the right area according to the positive or negative value of x;

[0078] Output the detection results of this period to achieve backward warning.

[0079] Beneficial effects

[0080] The system of the present invention changes the orientation state of the millimeter-wave radar device by vertically flipping or horizontally flipping the millimeter-wave radar device, obtains the orientation state of the millimeter-wave radar device through the orientation acquisition module, and the mode judgment module judges whether the millimeter-wave radar device enters the personnel perception mode or the backward warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module, and the control module controls the millimeter-wave radar device to enter the personnel perception mode or the backward warning mode according to the mode judgment result; when the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode, the millimeter-wave radar device loads the configuration parameters of the personnel perception mode, periodically executes radar detection, and outputs the detection results, thereby realizing personnel perception; when the detection direction of the millimeter-wave radar device is back to the driver, the backward warning mode is executed, the configuration parameters of the backward warning mode are loaded, the radar detection is periodically executed, and the detection results are output, thereby realizing backward warning;

[0081] The present invention can automatically realize the presence perception of the driver of a two-wheeled vehicle or the warning of rearward vehicles by adjusting the detection direction of the millimeter wave radar device to face the driver forward and face the back of the driver, thereby providing users with two safety detection functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0083] Figure 1 It is a schematic structural diagram of a vertical flip millimeter wave radar device of the present invention;

[0084] Figure 2 It is a schematic structural diagram of a horizontal flip millimeter wave radar device of the present invention;

[0085] Figure 3 The schematic diagram of the millimeter wave radar system for two-wheeled vehicles with human body perception and rear warning functions of the present invention;

[0086] Figure 4 It is a flow chart of each detection cycle of the millimeter wave radar device in the personnel perception mode of the present invention;

[0087] Figure 5 This is a flow chart of each detection cycle of the millimeter wave radar device in the backward warning mode of the present invention. DETAILED DESCRIPTION

[0088] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0089] The present invention will be further described below in conjunction with the embodiments.

[0090] Example 1

[0091] Please refer to the instruction manual Figures 3-5 , a two-wheeled vehicle millimeter wave radar system with human perception and rear warning functions, including a millimeter wave radar device capable of adjusting the detection direction to be forward toward the driver and backward toward the driver;

[0092] Preferably, the millimeter-wave radar device adopts a vertical flip millimeter-wave radar device or a horizontal flip millimeter-wave radar device; the difference between the two is that the flipping method of adjusting the detection direction is different, the vertical flip millimeter-wave radar device can realize vertical flipping to adjust the detection direction, and the horizontal flip millimeter-wave radar device can realize horizontal flipping to adjust the detection direction;

[0093] A direction acquisition module, which acquires the direction status of the millimeter wave radar device;

[0094] A mode judgment module, which judges whether the millimeter-wave radar device enters a personnel perception mode or a rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module;

[0095] The control module controls the millimeter-wave radar device to enter the personnel perception mode or the rear warning mode according to the mode judgment result.

[0096] A. When the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode, the millimeter-wave radar device loads the configuration parameters of the personnel perception mode, performs radar detection periodically, and outputs the detection results.

[0097] Please refer to the instruction manual Figure 4 In the personnel sensing mode, the process steps of each detection cycle of the millimeter wave radar device are as follows:

[0098] 1.1) The millimeter wave radar device sends a frequency modulated continuous pulse signal through a TX antenna, and receives the reflected echo signal of the target through two radar receiving antennas RX, mixes and demodulates the echo signal to obtain two ADC (analog-to-digital converter) data, and caches the data;

[0099] 1.2) Perform the fast frame operation, perform 1D-FFT (one-dimensional Fourier transform) processing on the two-channel ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT (two-dimensional fast Fourier transform) processing based on the result to obtain the spectrum in the Doppler dimension, and remove the information with a Doppler velocity of 0; Perform CFAR (constant false alarm rate) and angle estimation on the FFT (fast Fourier transform) results obtained twice to obtain the target point cloud data of the moving point;

[0100] 1.3) Determine whether the number of cached data frames reaches 32. If not, directly proceed to the next step. If so, perform the slow frame operation. After performing mean processing on the cached 32-frame ADC data, perform 1D-FFT and 2D-FFT processing, and through CFAR and angle estimation, obtain the target point cloud of the static point, and release the cached data;

[0101] 1.4) Perform density-based clustering methods on the target point cloud data of the moving point and the static point respectively, output the moving target data and the static target data, and perform α-β filtering processing on the data;

[0102] 1.5) Output the obtained target tracks to the function layer for screening and position judgment of the target data.

[0103] In step 1.5), the implementation steps of the function layer include:

[0104] One: Preprocess the target data and剔除 invalid targets: 0 <= range (range) <= range_max (the maximum detection distance of the radar), -60° < angle (angle) < 60°. When there is no target, output the unmanned state. When there is a target, proceed to the next operation;

[0105] Two: Calculate the target coordinate points (x, y) for valid targets:

[0106] x = range * sin(angle);

[0107] y = range * cos(angle);

[0108] Obtain the position points (x, y) of the target;

[0109] III: Determine whether there is a target in the driving area based on the coordinate values of all targets, where x_valid_min1 < x < x_valid_max1 and 0 < y < y_valid_max1. Here, x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis. If there is no target in the driving area, record it as the driver being out of the vehicle state; if there is a target in the driving area, record it as the driver entering the vehicle state.

[0110] IV: Output the personnel monitoring result to achieve personnel perception.

[0111] B. When the detection direction of the millimeter-wave radar device is backward from the driver, execute the rear warning mode, load the configuration parameters of the rear warning mode, perform radar detection periodically, and output the detection result.

[0112] Please refer to the attached instructions Figure 5 , in the rear warning mode, the process steps of each detection cycle of the millimeter-wave radar device are as follows:

[0113] 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through one TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. Mix and demodulate the echo signals to obtain two channels of ADC data.

[0114] 2.2) Perform 1D-FFT processing on the two channels of ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension; perform CFAR and angle estimation on the FFT results obtained twice, and use the different ambiguous speeds generated by the two waveforms to perform speed deblurring to obtain the point cloud data of the target;

[0115] 2.3) Perform a density-based clustering method according to the point cloud data, output the target data, including the azimuth angle, distance, and speed of the target, and perform EKF (Extended Kalman Filter) filtering processing on the target data to achieve target tracking, and input the result into the function layer;

[0116] 2.4) The function layer calculates based on the speed and azimuth of the target, determines whether there is a target that meets the alarm condition, and outputs the result.

[0117] In step 2.4), the implementation steps of the function layer include:

[0118] 1. Preprocess the target data, filter out the targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and eliminate the invalid targets;

[0119] 2. Calculate the target coordinate points (x, y) for the valid targets:

[0120] x = range * sin(angle);

[0121] y = range * cos(angle);

[0122] Obtain the position points (x, y) of the target;

[0123] 3. Based on the coordinate values of the target, determine whether it is in the alarm area, x_valid_min < x < x_valid_max, where x_valid_min represents the minimum value within the alarm area on the X-axis, and x_valid_max represents the maximum value within the alarm area on the X-axis;

[0124] If it is not in the alarm area, eliminate the target. At the same time, establish a speed constraint for the target. When the relative speed of the target is negative, eliminate the target. If the relative speed of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and speed; where TTC represents the possible collision time of the target, range represents the distance of the target relative to the radar, and vel represents the relative speed of the target to the radar.

[0125] 4. When there is a situation where TTC < 3s for all the remaining targets, an alarm needs to be issued and the alarm area needs to be judged. The alarm area is divided into two parts, the left and the right. Determine whether it is the left area or the right area according to the positive or negative value of the x value;

[0126] 5. Output the detection results of this cycle to achieve backward warning.

[0127] The present invention can automatically realize the detection of the presence of the driver of the two-wheeler or the warning of oncoming vehicles from behind by adjusting the detection direction of the millimeter-wave radar device to face the driver forward and backward, thus providing two safety detection functions for users.

[0128] Example 2

[0129] Please refer to the attached instructions Figure 1The vertical flip millimeter wave radar device includes a radar module 1 and a mounting bracket A2, the mounting bracket A2 is a U-shaped bracket, and the two ends of the radar module 1 are respectively fixedly connected with a flip shaft 22, and the two flip shafts 22 are respectively rotatably connected to the two ends of the mounting bracket A2; the upper parts of both ends of the mounting bracket A2 are provided with a wire groove 21, and the bottom of the mounting bracket A2 is provided with a plurality of mounting holes A23, and the mounting bracket A2 is fixedly connected to the two-wheeled vehicle through the mounting holes A23.

[0130] The radar module 1 can be rotated manually, and a 180° vertical flip can be achieved through the flip axis 22; the outgoing wires inside the radar module 1 can pass through the wire slot 21 to achieve flipping without interference.

[0131] Example 3

[0132] Please refer to the instruction manual Figure 2 The horizontal flip millimeter wave radar device includes a radar module 1 and a mounting bracket B3. The mounting bracket B3 is a flat bracket. The bottom of the radar module 1 is fixedly connected to the flip shaft 31. The bottom of the flip shaft 31 is rotatably connected to the mounting bracket B3. A plurality of mounting holes B32 are provided on the mounting bracket B3. The mounting bracket B3 is fixedly connected to the two-wheeled vehicle through the mounting holes B32.

[0133] The radar module 1 can be rotated manually, and a 180° horizontal flip can be achieved through the flip axis 21 .

[0134] Example 4

[0135] Please refer to the instruction manual Figures 3-5 This embodiment discloses a detection method of a two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions, comprising the following steps:

[0136] S1. Adjust the detection direction by rotating the millimeter wave radar device to face the driver or face away from the driver;

[0137] S2, the orientation acquisition module acquires the orientation state of the millimeter wave radar device;

[0138] S3, the mode judgment module judges whether the millimeter-wave radar device enters the personnel perception mode or the rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module;

[0139] S4, the control module controls the millimeter wave radar device to enter the personnel perception mode or the backward warning mode according to the mode judgment result;

[0140] A. When the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode. The millimeter-wave radar device loads the configuration parameters of the personnel perception mode and performs radar detection periodically. The process steps of each detection cycle are:

[0141] 1.1) The millimeter-wave radar device transmits a frequency-modulated continuous pulse signal through a TX antenna, and receives the reflected echo signal of the target through two radar receiving antennas RX. The echo signal is mixed and demodulated to obtain two-channel ADC (analog-to-digital converter) data, and the data is cached.

[0142] 1.2) Perform a fast frame operation, perform 1D-FFT (one-dimensional Fourier transform) processing on the two-channel ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT (two-dimensional fast Fourier transform) processing based on the result to obtain the spectrum in the Doppler dimension, and remove the information with a Doppler velocity of 0; perform CFAR (constant false alarm rate) and angle estimation on the FFT (fast Fourier transform) results obtained twice to obtain the target point cloud data of the moving point.

[0143] 1.3) Determine whether the number of cached data frames reaches 32. If not, directly proceed to the next step. If so, perform a slow frame operation. After averaging the 32-frame ADC data in the cache, perform 1D-FFT and 2D-FFT processing, and obtain the target point cloud of the static point through CFAR and angle estimation, and release the cached data.

[0144] 1.4) Perform density-based clustering methods on the target point cloud data of the moving point and the static point respectively, output the moving target data and the static target data, and perform α-β filtering processing on the data.

[0145] 1.5) Output the obtained target tracks to the function layer, and the function layer performs the following steps:

[0146] Preprocess the target data and剔除 the invalid targets: 0 <= range (range) <= range_max (the maximum detection distance of the radar), -60° < angle (angle) < 60°. When there is no target, output the unmanned state. When there is a target, perform the next operation.

[0147] Calculate the target coordinate points (x, y) for the valid targets:

[0148] x = range * sin(angle);

[0149] y = range * cos(angle);

[0150] Obtain the position points (x, y) of the target.

[0151] Based on the coordinate values of all targets, determine whether there is a target in the driving area, where x_valid_min1 < x < x_valid_max1 and 0 < y < y_valid_max1. Here, x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis. If there is no target in the driving area, record it as the driver leaving the vehicle state; if there is a target in the driving area, record it as the driver entering the vehicle state;

[0152] Output the personnel monitoring result to achieve personnel perception;

[0153] B. When the detection direction of the millimeter-wave radar device is backward from the driver, execute the rear warning mode, load the configuration parameters of the rear warning mode, and perform radar detection periodically. The process steps for each detection cycle are as follows:

[0154] 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through one TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. Mix and demodulate the echo signals to obtain two channels of ADC data;

[0155] 2.2) Perform 1D-FFT processing on the two channels of ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension. Perform CFAR and angle estimation on the two obtained FFT results, and use the different ambiguous speeds generated by the two waveforms to perform speed deblurring to obtain the point cloud data of the target;

[0156] 2.3) Perform a density-based clustering method based on the point cloud data, output the target data, including the azimuth angle, distance, and speed of the target, and perform EKF (Extended Kalman Filter) filtering processing on the target data to achieve target tracking, and input the result into the functional layer;

[0157] 2.4) The functional layer performs the following steps:

[0158] Preprocess the target data, filter out the targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and剔除 the invalid targets;

[0159] Calculate the target coordinate points (x, y) for the valid targets:

[0160] x = range * sin(angle);

[0161] y = range * cos(angle);

[0162] Obtain the position point (x, y) of the target;

[0163] Based on the coordinate values of the target, determine whether it is in the alarm area, where x_valid_min < x < x_valid_max. Here, x_valid_min represents the minimum value within the alarm area on the X-axis, and x_valid_max represents the maximum value within the alarm area on the X-axis;

[0164] If it is not in the alarm area, eliminate the target. At the same time, establish the speed constraint of the target. When the relative speed of the target is negative, eliminate the target. If the relative speed of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and speed; where TTC represents the possible collision time of the target, range represents the distance of the target relative to the radar, and vel represents the relative speed of the target to the radar;

[0165] When there is a situation where TTC < 3s for all remaining targets, an alarm is required and the alarm area is judged. The alarm area is divided into two parts, left and right. Determine whether it is the left area or the right area according to the positive or negative value of the x;

[0166] Output the detection result of this cycle, so as to realize the backward warning.

[0167] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions, characterized in that it includes a millimeter wave radar device that can adjust the detection direction to face the driver forward and face the driver backward; A direction acquisition module, which acquires the direction status of the millimeter wave radar device; A mode judgment module, which judges whether the millimeter-wave radar device enters a personnel perception mode or a rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module; A control module controls the millimeter wave radar device to enter a personnel sensing mode or a backward warning mode according to a mode judgment result; When the detection direction of the millimeter-wave radar device is forward toward the driver, the control module controls the millimeter-wave radar device to execute the personnel perception mode, the millimeter-wave radar device loads the configuration parameters of the personnel perception mode, periodically performs radar detection, and outputs the detection results; When the detection direction of the millimeter wave radar device is facing away from the driver, the rear warning mode is executed, the configuration parameters of the rear warning mode are loaded, the radar detection is performed periodically, and the detection results are output; The millimeter wave radar device adopts a vertical flip type millimeter wave radar device or a horizontal flip type millimeter wave radar device; In the personnel sensing mode, the process steps of each detection cycle of the millimeter wave radar device are as follows: 1.1) The millimeter-wave radar device transmits a frequency-modulated continuous pulse signal through a TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. The echo signals are mixed and demodulated to obtain two channels of ADC data, and the data is cached. 1.2) Perform a fast frame operation, perform 1D-FFT processing on the two channels of ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension, and remove the information with a Doppler velocity of 0; perform CFAR and angle estimation on the FFT results obtained twice to obtain the target point cloud data of the moving point. 1.3) Determine whether the number of cached data frames reaches 32. If not, directly proceed to the next step. If so, perform a slow frame operation. After averaging the 32 frames of cached ADC data, perform 1D-FFT and 2D-FFT processing, and through CFAR and angle estimation, obtain the target point cloud of the static point, and release the cached data. 1.4) Perform density-based clustering methods on the target point cloud data of the moving point and the static point respectively, output the moving target data and the static target data, and perform α-β filtering processing on the data. 1.5) Output the obtained target tracks to the functional layer for screening and position judgment of the target data.

2. The two-wheeled vehicle millimeter wave radar system with human perception and rear warning functions according to claim 1 is characterized in that: In step 1.5), the implementation steps of the functional layer include: One: Preprocess the target data and剔除 the invalid targets: 0 <= range <= range_max, -60° < angle < 60°. When there is no target, output the no-person state. When there is a target, proceed to the next operation. Two: Calculate the target coordinate points (x, y) for the valid targets: x = range * sin(angle); y = range * cos(angle); Obtain the position points (x, y) of the target; where range represents the distance of the target relative to the radar, range_max represents the maximum detectable distance of the radar, and angle represents the angle; Three: Based on the coordinate values of all targets, determine whether there is a target in the driving area, x_valid_min1 < x < x_valid_max1, 0 < y < y_valid_max1, where x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis; if there is no target in the driving area, record it as the driver-off-the-vehicle state. If there is a target in the driving area, record it as the driver-entering-the-vehicle state; Four: Output the personnel monitoring results.

3. The two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 2 is characterized in that: In the rear warning mode, the process steps of the millimeter-wave radar device for each detection cycle are: 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through a TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. The echo signals are mixed and demodulated to obtain two channels of ADC data; 2.2) Perform 1D-FFT processing on the two-channel ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension; perform CFAR and angle estimation on the FFT results obtained twice, and use the different ambiguous velocities generated by the two waveforms to perform velocity ambiguity resolution to obtain the point cloud data of the target; 2.3) Perform density-based clustering method according to the point cloud data, output the target data, including the azimuth angle, distance, and velocity of the target, and perform EKF filtering processing on the target data to achieve target tracking, and input the result into the function layer; 2.4) The function layer calculates based on the velocity and azimuth of the target, determines whether there is a target that meets the alarm condition, and outputs the result.

4. The two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 3 is characterized in that: In step 2.4), the implementation steps of the function layer include: One: Preprocess the target data, filter out the targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and剔除 the invalid targets; Two: Calculate the target coordinate points (x, y) for the valid targets: x = range * sin(angle); y = range * cos(angle); Obtain the position points (x, y) of the target; Three: Judge whether it is in the alarm area based on the coordinate values of the target, x_valid_min < x < x_valid_max, where x_valid_min represents the minimum value in the alarm area on the X-axis, and x_valid_max represents the maximum value in the alarm area on the X-axis; If it is not in the alarm area,剔除该 target, and at the same time establish the velocity constraint of the target. When the relative velocity of the target is negative,剔除该 target. If the relative velocity of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and velocity; where TTC represents the possible collision time of the target, and vel represents the relative velocity of the target to the radar; Four: When there is a situation where TTC < 3s for all the remaining targets, an alarm needs to be issued and the alarm area needs to be judged. The alarm area is divided into two parts, the left and the right. Judge whether it is the left area or the right area according to the positive or negative value of the x value; Five: Output the detection result of this cycle.

5. The two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 4 is characterized in that: The vertical flip type millimeter wave radar device includes a radar module (1) and a mounting bracket A (2). Both ends of the radar module (1) are fixedly connected with a flip shaft (22), and the two flip shafts (22) are respectively rotationally connected with both ends of the mounting bracket A (2); through slots (21) are respectively opened at the upper parts of both ends of the mounting bracket A (2), and a plurality of mounting holes A (23) are opened at the bottom of the mounting bracket A (2). The mounting bracket A (2) is fixedly connected with a two-wheeled vehicle through the mounting holes A (23).

6. The two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 5 is characterized in that: The horizontal flip type millimeter wave radar device includes a radar module (1) and a mounting bracket B (3). The bottom of the radar module (1) is rotationally connected with the mounting bracket B (3) through a flip shaft. A plurality of mounting holes B (32) are opened on the mounting bracket B (3), and the mounting bracket B (3) is fixedly connected with a two-wheeled vehicle through the mounting holes B (32).

7. The two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 6 is characterized in that: The bottom of the radar module (1) is fixedly connected to the rotation axis (31), and the bottom of the rotation axis (31) is rotatably connected to the mounting bracket B (3).

8. A detection method for a two-wheeled vehicle millimeter wave radar system with human body perception and rear warning functions according to claim 7, characterized in that: It includes the following steps: S1. Adjust the detection direction of the millimeter-wave radar device by rotation to face the driver forward or backward; S2. The orientation acquisition module acquires the orientation state of the millimeter-wave radar device; S3. The mode judgment module judges whether the millimeter-wave radar device enters the personnel perception mode or the rear warning mode according to the orientation state of the millimeter-wave radar device, and outputs the mode judgment result to the control module; S4. The control module controls the millimeter-wave radar device to enter the personnel perception mode or the rear warning mode according to the mode judgment result; A. When the detection direction of the millimeter-wave radar device is facing the driver forward, the control module controls the millimeter-wave radar device to execute the personnel perception mode. The millimeter-wave radar device loads the configuration parameters of the personnel perception mode and performs radar detection periodically. The process steps of each detection cycle are as follows: 1.1) The millimeter-wave radar device sends a frequency-modulated continuous pulse signal through one TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. The echo signals are mixed and demodulated to obtain two-way ADC data, and the data is cached; 1.2) Perform a fast frame operation, perform 1D-FFT processing on the two-way ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the result to obtain the spectrum in the Doppler dimension, and remove the information with a Doppler velocity of 0; Perform CFAR and angle estimation on the two obtained FFT results to obtain the target point cloud data of the moving point; 1.3) Judge whether the number of cached data frames reaches 32. If not, directly proceed to the next step. If so, perform a slow frame operation. After the 32-frame ADC data in the cache is averaged, perform 1D-FFT and 2D-FFT processing, and through CFAR and angle estimation, obtain the target point cloud of the static point, and release the cached data; 1.4) Perform density-based clustering methods on the target point cloud data of the moving point and the static point respectively, output the moving target data and the static target data, and perform α-β filtering processing on the data; 1.5) Output the obtained target tracks to the function layer, and the function layer implements the following steps: Preprocess the target data and剔除 the invalid targets: 0 <= range <= range_max, -60° < angle < 60°. When there is no target, output the no-person state. When there is a target, perform the next operation; Calculate the target coordinate points (x, y) for the valid targets: x = range * sin(angle); y = range * cos(angle); Obtain the position points (x, y) of the target; Based on the coordinate values of all targets, determine whether there is a target in the driving area, where x_valid_min1 < x < x_valid_max1 and 0 < y < y_valid_max1. Here, x_valid_min1 represents the minimum value within the valid area on the X-axis, x_valid_max1 represents the maximum value within the valid area on the X-axis, and y_valid_max1 represents the maximum value within the valid area on the Y-axis. If there is no target in the driving area, record it as the driver leaving the vehicle state. If there is a target in the driving area, record it as the driver entering the vehicle state. Output the personnel monitoring result to achieve personnel perception. B. When the detection direction of the millimeter-wave radar device is backward from the driver, execute the rear warning mode, load the configuration parameters of the rear warning mode, and perform radar detection periodically. The process steps for each detection cycle are as follows: 2.1) The millimeter-wave radar device alternately transmits mutually staggered frequency-modulated continuous pulse signals A and B through one TX antenna, and receives the reflected echo signals of the target through two radar receiving antennas RX. Mix and demodulate the echo signals to obtain two channels of ADC data. 2.2) Perform 1D-FFT processing on the two channels of ADC data to obtain the spectrum in the range dimension, and perform 2D-FFT processing based on the results to obtain the spectrum in the Doppler dimension. Perform CFAR and angle estimation on the FFT results obtained twice, and use the different ambiguous speeds generated by the two waveforms to perform speed ambiguity resolution to obtain the point cloud data of the target. 2.3) Perform a density-based clustering method according to the point cloud data, output the target data, including the azimuth angle, distance, and speed of the target, and perform EKF filtering processing on the target data to achieve target tracking, and input the results into the functional layer. 2.4) The functional layer performs the following steps: Preprocess the target data to filter out targets outside the detection range: 0 <= range <= range_max, -60° < angle < 60°, and剔除 the invalid targets. Calculate the target coordinate points (x, y) for the valid targets: x = range * sin(angle); y = range * cos(angle); Obtain the position points (x, y) of the target. Based on the coordinate values of the target, determine whether it is in the alarm area, where x_valid_min < x < x_valid_max. Here, x_valid_min represents the minimum value within the alarm area on the X-axis, and x_valid_max represents the maximum value within the alarm area on the X-axis. If it is not in the alarm area,剔除 the target. At the same time, establish the speed constraint of the target. When the relative speed of the target is negative,剔除 the target. If the relative speed of the target is positive, calculate the possible collision time TTC = range / vel according to the distance and speed. Here, TTC represents the possible collision time of the target, range represents the distance of the target relative to the radar, and vel represents the relative speed of the target to the radar. When the TTC of all remaining targets is less than 3s, an alarm is required and the alarm area is determined. The alarm area is divided into left and right parts. The positive or negative value of x determines whether it is the left area or the right area. Output the detection results of this cycle to achieve backward warning.

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