Method and system for measuring front view of agricultural machine driver and readable storage medium

Abstract

The invention discloses an agricultural machinery driver front view measurement method and system and a readable storage medium, and belongs to the field of agricultural machinery measurement, and the method comprises the steps: collecting a sensor signal when a rotating platform rotates; the sensor signals are analyzed in real time, and sensor measurement point numerical value changes are obtained and used for sensing whether the sensor passes through a shielding object or not; when a shielding object is encountered, the distance between the measurement position of the sensor and the two ends of the first shielding object and the rotation angle difference are calculated; and along with the rotation of the rotation platform, circularly calculating the distance and the rotation angle difference between the measurement position of the sensor and the two ends of other shelters, and respectively substituting the distances and the rotation angle differences into the sheltering shadow calculation model for solving to obtain the sheltering shadow chord length of each shelter in the field of view of the agricultural machine. According to the method, the shielding shadow chord lengths of all shielding objects in the field of view of the agricultural machine can be calculated, and the shielding shadow chord length mean value in the field of view of the agricultural machine is obtained and used for front-field safety analysis of agricultural machine drivers.

Description

Technical Field

[0001] The invention relates to a method, a system and a readable storage medium for measuring the front visual field of an agricultural machinery driver, and belongs to the field of agricultural machinery measurement. Background Art

[0002] Agricultural machinery travels on poor roads and has a complex working environment. In order to reduce the driver's labor intensity and improve work quality and efficiency, it is necessary to automatically measure the driver's field of view for agricultural machinery equipped with a cab, especially agricultural tractors.

[0003] In traditional measurements, surveyors must use large light sources, tape measures and other tools to perform manual measurements at night, which is very cumbersome and complicated, and the measurement accuracy is easily affected by external factors.

[0004] At present, the measurement of the front field of vision of vehicle drivers also uses a full set of automobile field of vision detection equipment consisting of a three-coordinate measuring machine, a laser field of vision tester and an eye point simulator to measure the field of vision of vehicles. However, this measurement method requires the use of large instruments, is cumbersome to operate, is greatly affected by human factors, and is not easy to be used outdoors for agricultural machinery driver field of vision measurement. Some people also use a host computer combined with a camera to simulate the pupil of the human eye using a wide-angle lens aperture diaphragm for measurement, but this method does not simulate the movement of the driver's eyes well, and requires the use of a desktop computer, which is not convenient for outdoor measurement.

[0005] Therefore, the present invention proposes a method that can provide high-precision measurement for agricultural machinery drivers, effectively avoiding the problems that tractors and other agricultural machinery may encounter during the field of view measurement process. Summary of the invention

[0006] The purpose of the present invention is to provide a method, system and readable storage medium for measuring the front visual field of an agricultural machinery driver, which can solve the problem of low visual field measurement accuracy of existing agricultural machinery and tractors.

[0007] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions.

[0008] A method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor, comprising:

[0009] After power is supplied, a control command for the rotating platform is generated to drive the rotating platform to move, and sensor signals are collected at the same time;

[0010] The sensor signal is analyzed in real time according to the set signal threshold, and the value change of the sensor measurement point is obtained to determine whether the sensor's measurement position passes through an obstruction;

[0011] If an obstruction is encountered, the distance and rotation angle difference between the sensor's measurement position and the two ends of the first obstruction are calculated based on the sensor signal; and as the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically; the measurement ends when the rotating platform rotates beyond 180°;

[0012] If there is no obstruction, the platform will continue to rotate until it exceeds 180° and the measurement ends;

[0013] Substitute the difference between the distance between the two ends and the rotation angle of each shielding object within the field of view of the agricultural machinery into the shielding shadow calculation model for calculation, and obtain the shielding shadow chord length of each shielding object within the field of view of the agricultural machinery;

[0014] The chord lengths of shadows of all obstructions within the field of view of the agricultural machinery are calculated to obtain the average chord length of shadows within the field of view of the agricultural machinery, which is used for the safety analysis of the forward field of view of the agricultural machinery driver.

[0015] Optionally, the sensor signal is analyzed in real time according to a set signal threshold to obtain a value change of the sensor measurement point to determine whether the measurement position of the sensor passes through an obstruction, including:

[0016] By comparing the set signal threshold with the sensor signal, it is determined whether the sensor measurement position passes through an obstruction and the relative position change between the measurement position and the obstruction;

[0017] If the sensor signal is greater than the set signal threshold, most of the light is transmitted by the glass, and the sensor's measurement position is the glass, and no obstruction is encountered;

[0018] If the sensor signal decreases from large to the set signal threshold, the sensor's measurement position moves from the side glass to one end of the obstruction and begins to encounter the obstruction;

[0019] If the sensor signal increases from a small value to a large value above the set signal threshold, the measuring position of the sensor moves from the other end of the shielding object to the side glass and passes through the shielding object.

[0020] Optionally, if an obstruction is encountered, the distance and rotation angle difference between the measurement position of the sensor and the two ends of the first obstruction are calculated according to the sensor signal; and as the rotating platform rotates, the distance and rotation angle difference between the measurement position of the sensor and the two ends of other obstructions are calculated cyclically; until the rotating platform rotates beyond 180°, the measurement is terminated, including:

[0021] When the measuring position of the sensor is from the side glass to one end of the shielding object, the distance and rotation angle between the measuring position of the sensor and one end of the shielding object are calculated according to the sensor signal;

[0022] When the measuring position of the sensor moves from the other end of the shielding object to the side glass, the distance and the rotation angle difference between the measuring position of the sensor and the other end of the shielding object are calculated according to the sensor signal;

[0023] As the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically to obtain the distance and rotation angle difference between the two ends of each obstruction within the field of view of the agricultural machinery, until the measurement is terminated when the rotating platform rotates more than 180°.

[0024] Optionally, it also includes performing data point curve fitting on the sensor signal after the measurement is completed to obtain a fitting curve of the measurement data points;

[0025] Find the data points associated with the sawtooth curve from the fitting curve and define them as invalid data; wherein the invalid data are all the data points in the sawtooth curve except the tooth root;

[0026] Filter invalid data to obtain valid data;

[0027] Based on the valid data, the difference between the distance between the two ends and the rotation angle of each shielding object is re-find.

[0028] Optionally, the expression of the occlusion shadow calculation model is:

[0029]

[0030] In the formula, is the position of the displacement sensor, They are the two ends of the shadow chord length, is the chord length of the shadow of the obstruction, is the distance from one end of the shadow chord to the displacement sensor, is the distance from the other end of the shadow chord to the displacement sensor, It is the difference between the angles between the two ends of the shadow chord and the displacement sensor, that is, the rotation angle.

[0031] Optionally, the chord lengths of the shadows of all obstructions within the field of view of the agricultural machinery are calculated to obtain the average chord lengths of the shadows within the field of view of the agricultural machinery, and further include:

[0032] The number and position distribution of shadows of all obstructions within the field of view of the agricultural machinery are counted to obtain other field of view data of the obstructions.

[0033] Optionally, the agricultural machinery driver's front vision safety analysis may also include:

[0034] If the mean chord length of the shadows within the agricultural machinery field of view meets the preset agricultural machinery field of view quality threshold, the agricultural machinery field of view safety measurement result is obtained;

[0035] If the mean chord length of the obstruction shadow within the agricultural machinery's field of view does not meet the preset agricultural machinery field of view quality threshold, an unsafe measurement result of the agricultural machinery field of view is obtained, and a parameter table of obstruction measurement information and a curve diagram of the obstruction position distribution and size are generated to provide reference data for optimizing the field of view.

[0036] A displacement sensor-based front vision measurement system for an agricultural machinery driver, comprising:

[0037] Host computer, rotating platform, displacement sensor and development board controller;

[0038] The driving motor of the rotating platform is electrically connected to the upper computer and is used to generate a control instruction for the rotating platform to drive the rotating platform to move;

[0039] The displacement sensor is mounted on the rotating platform and is electrically connected to the development board controller;

[0040] The host computer communicates with the development board controller via the UART protocol, receives the signal fed back by the sensor and executes the steps of the above method.

[0041] Optionally, the displacement sensor is installed 670 mm above the agricultural machinery seat and 10 mm in front of the seat; the measuring distance of the displacement sensor is 7 m.

[0042] Optionally, the development board controller receives data from the displacement sensor through a signal line, and performs analog voltage signal processing on the data to obtain accurate distance information;

[0043] Upload the accurate distance information to the host computer, and continuously send the rotation angle information to the host computer.

[0044] A computer-readable storage medium stores a computer program, which implements the steps of the above method when executed by a processor.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] Compared with traditional measurement methods, this method can reduce the tediousness of manual measurement and does not require complex and precise field of view measurement equipment. It only requires the sensor to measure the distance and rotation angle difference between the position and both ends of all obstructions to obtain the chord length of the shadow of each obstruction, quickly obtain the agricultural machinery field of view measurement results, and generate a field of view safety assessment report.

[0047] The visual field safety assessment report generates a table of obstruction measurement information parameters and a curve diagram of obstruction location distribution and size to provide reference data for optimizing the visual field. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 Shown is a flow chart of a method for measuring the front visual field of an agricultural machine driver according to the present invention;

[0049] Figure 2 Shown is a schematic diagram of the calculation of the mathematical model of the present invention;

[0050] Figure 3 The figure shows an embodiment of the semicircle of the front visual field of the agricultural machine driver of the present invention;

[0051] Figure 4 The figure shows an embodiment of the front visual field measurement system for the agricultural machine driver of the present invention;

[0052] Figure 5 The figure shows a hardware assembly diagram of the front visual field measurement system for the agricultural machine driver of the present invention;

[0053] Figure 6 The network topology diagram of the front vision measurement system for agricultural machinery drivers of the present invention is shown as follows

[0054] Figure 7 Shown is a flow chart of the method for measuring the front visual field of an agricultural machinery driver of the present invention.

[0055] Figure numerals: 1-electrical cabinet, 2-rotating platform, 3-displacement sensor, 4-development board controller, 5-power supply, 6-driver. DETAILED DESCRIPTION

[0056] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0057] Example 1

[0058] This embodiment provides a method for measuring the front vision of an agricultural machinery driver based on a displacement sensor. Figure 1 Shown include:

[0059] Step 1: After startup, generate the control command of the rotating platform to drive the rotating platform to move, and start to obtain the sensor signal at the same time;

[0060] Step 2: Analyze the sensor signal in real time according to the set signal threshold, and obtain the refractive index of the sensor measurement point to determine whether the sensor's measurement position passes through an obstruction;

[0061] Step 3: If an obstruction is encountered, the distance and rotation angle difference between the sensor's measurement position and the two ends of the first obstruction are calculated based on the sensor signal; and as the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically; the measurement ends when the rotating platform rotates beyond 180°;

[0062] If there is no obstruction, the platform will continue to rotate until it exceeds 180° and the measurement ends;

[0063] Step 4: Substitute the distance between the two ends and the difference in rotation angle of each shielding object within the field of view of the agricultural machinery into the shielding shadow calculation model for calculation to obtain the shielding shadow chord length of each shielding object within the field of view of the agricultural machinery;

[0064] Step 5: Calculate the chord length of the shadows of all obstructions within the field of view of the agricultural machinery to obtain the average chord length of the shadows within the field of view of the agricultural machinery, which is used for the safety analysis of the forward field of view of the agricultural machinery driver.

[0065] In this embodiment, after the system is powered on, the host computer can communicate with the development board controller by clicking the serial port connection. Click to start measuring, the rotating platform starts to rotate, and drives the displacement sensor connected to the top to rotate together. The host computer displays the distance measured by the sensor at this time. When the sensor's measurement position is from the side glass to the shield, the host computer records the distance from the sensor to the shield at this moment, and records the rotation angle at this moment, until the sensor's measurement position is not on the shield, records the distance at this moment, and records the rotation angle at this moment, and displays the difference on the host computer interface. In this cycle, the difference between the distance and rotation angle of each end of each shield is continuously measured, and each set of data is recorded until the photoelectric sensor is triggered to return to zero after rotating 180°.

[0066] Optionally, in step 2, the sensor signal is analyzed in real time according to a set signal threshold to obtain a material change at the sensor measurement position to determine whether the sensor measurement position passes through an obstruction, including:

[0067] By comparing the set signal threshold with the sensor signal, it is determined whether the sensor measurement position passes through an obstruction and the relative position change between the measurement position and the obstruction;

[0068] If the sensor signal is greater than the set signal threshold, most of the light is transmitted by the glass, and the sensor's measurement position is the glass, and no obstruction is encountered;

[0069] If the sensor signal decreases from large to the set signal threshold, the sensor's measurement position moves from the side glass to one end of the obstruction and begins to encounter the obstruction;

[0070] If the sensor signal increases from a small value to a large value above the set signal threshold, the measuring position of the sensor moves from the other end of the shielding object to the side glass and passes through the shielding object.

[0071] Optionally, if an obstruction is encountered in step 3, the distance and rotation angle difference between the measurement position of the sensor and the two ends of the first obstruction are calculated according to the sensor signal; and as the rotating platform rotates, the distance and rotation angle difference between the measurement position of the sensor and the two ends of other obstructions are calculated cyclically; until the rotating platform rotates beyond 180°, the measurement is terminated, including:

[0072] When the measuring position of the sensor is from the side glass to one end of the shielding object, the distance and rotation angle between the measuring position of the sensor and one end of the shielding object are calculated according to the sensor signal;

[0073] When the measuring position of the sensor moves from the other end of the shielding object to the side glass, the distance and the rotation angle difference between the measuring position of the sensor and the other end of the shielding object are calculated according to the sensor signal;

[0074] As the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically to obtain the distance and rotation angle difference between the two ends of each obstruction within the field of view of the agricultural machinery, until the measurement is terminated when the rotating platform rotates more than 180°.

[0075] Optionally, due to different obstructions, especially when the sensor measures the black edge and sealing strip on the edge of the tractor window, the black edge and sealing strip have poor reflectivity to the laser, which easily leads to measurement data fluctuations and data surges. We choose to collect a large number of data points during the entire measurement process. The data points include sensor displacement information and platform rotation angle information, and then filter the data points to filter out invalid data near the black edge and sealing strip. After that, curve fitting is performed on the data. According to the judgment method mentioned above, the data points at both ends of each obstruction are found again, and then calculated to obtain the results; specifically:

[0076] After the measurement is completed, the sensor signal is subjected to data point curve fitting to obtain a fitting curve of the measured data points;

[0077] Find the data points associated with the sawtooth curve from the fitting curve and define them as invalid data;

[0078] Filter invalid data to obtain valid data;

[0079] Based on the valid data, the difference between the distance between the two ends and the rotation angle of each shielding object is re-find.

[0080] In this embodiment, invalid data refers to all data points in the sawtooth curve except the tooth root. The reason for this is that when the sensor measures the black edge and the sealing strip, due to the laser reflection characteristics of the black edge and the sealing strip themselves, the laser may not be reflected back to the sensor. At this time, the sensor displays a sudden increase in data, and the effect is like measuring on glass, which will affect our subsequent judgment of whether the mutation point is the distance between the two end points of the shielding object. Therefore, in order to avoid the influence of such invalid data, we will filter the sawtooth curve, remove the invalid data, and retain other non-sawtooth data.

[0081] Optionally, the expression of the occlusion shadow calculation model is:

[0082]

[0083] In the formula, is the position of the displacement sensor, They are the two ends of the shadow chord length, is the chord length of the shadow of the obstruction, is the distance from one end of the shadow chord to the displacement sensor, is the distance from the other end of the shadow chord to the displacement sensor, It is the difference between the angles between the two ends of the shadow chord and the displacement sensor, that is, the rotation angle.

[0084] In this embodiment, Figure 2 As shown, a and b are the left and right eye positions specified by the national standard, c and d are the two ends of the shield, and g is the midpoint of c and d. The specific calculation process in the upper computer software is as follows:

[0085] Known conditions: hc, hd and ∠chd are sent to the host computer by the development board controller. It is known that hf is 7m according to the national standard, and ah=bh=32.5mm. The calculation process is as follows:

[0086] S1. Calculate cd using the law of cosines.

[0087] S2.g is the midpoint of cd, and gh, ∠dhg and ∠chg are calculated by the law of cosines.

[0088] S3. All the data of triangle cdh are known, gh⊥ab, and ∠dhb and ∠cha can be obtained by calculation.

[0089] S4. Similarly, the data of triangle cha and triangle dhb can be calculated.

[0090] S5. For triangle fhb, hf is the radius, which is known. If hb and ∠fbh are known, the entire triangle can be calculated.

[0091] S6. From S5, we can calculate hf and ∠fhg. Similarly, we can calculate eh and ∠ehg.

[0092] S7. For triangle ehf, given eh, fh and ∠ehf=∠ehg+∠fhg, the length of ef, i.e. the length of the shadow chord of the shaded area, can be calculated.

[0093] Optionally, the chord lengths of the shadows of all obstructions within the field of view of the agricultural machinery are calculated to obtain the average chord lengths of the shadows within the field of view of the agricultural machinery, and further include:

[0094] The number and position distribution of shadows of all obstructions within the field of view of agricultural machinery are counted to obtain the field of view data of the number and position of obstructions.

[0095] Optionally, the agricultural machinery driver's front vision safety analysis may also include:

[0096] If the mean chord length of the shadows within the agricultural machinery field of view meets the preset agricultural machinery field of view quality threshold, the agricultural machinery field of view safety measurement result is obtained;

[0097] If the mean chord length of the obstruction shadow within the agricultural machinery's field of view does not meet the preset agricultural machinery field of view quality threshold, an unsafe measurement result of the agricultural machinery field of view is obtained, and a parameter table of obstruction measurement information and a curve diagram of the obstruction position distribution and size are generated to provide reference data for optimizing the field of view.

[0098] Example 2

[0099] This embodiment provides a front vision measurement system for an agricultural machine driver based on a displacement sensor 3, comprising:

[0100] Host computer, rotating platform 2, displacement sensor 3 and development board controller 4;

[0101] The driving motor of the rotating platform 2 is electrically connected to the upper computer and is used to generate a control instruction of the rotating platform 2 to drive the rotating platform 2 to move;

[0102] The displacement sensor 3 is installed on the rotating platform 2 and is electrically connected to the development board controller 4;

[0103] The host computer communicates with the development board controller 4 via the UART protocol, receives the signal fed back by the sensor and executes the steps of the above method.

[0104] In this embodiment, the rotating platform 2, the displacement sensor 3 and the development board controller 4 are assembled on the agricultural machine through the electrical cabinet 1. In addition, the electrical cabinet 1 is also equipped with a driver 6 and a power supply 5 to provide power and power for the rotating platform 2. Figure 3 and Figure 4The entire system shown is built in accordance with the national standard in a circle with a radius of 7m. The tractor is located at the center of the circle, and the measuring device is placed 670mm above the tractor seat and 10mm in front. The chord length of the shadow can be calculated as long as the measuring device can measure the distance to the two ends of the shield and the difference in the angle of rotation when passing through the two ends. The distance from the sensor to the shield can be collected by the displacement sensor 3 on the measuring device, and the development board controller 4 records the difference in the amount of pulses sent at the two ends of the shield, and converts it into the angle traveled when rotating from one end of the shield to the other end. During measurement, the operator controls the measurement process of the entire system through the host computer.

[0105] The rotating platform 2 is a rotating platform 2 on agricultural machinery, not limited to various agricultural machinery such as tractors.

[0106] The control core of the measurement system is the host computer, and all control instructions are issued by the host computer. Figure 5 and Figure 6 The remaining components shown include a development board controller 4, a rotating platform 2, a displacement sensor 3, a return to zero sensor, a mobile power supply 5, etc.

[0107] The main function of the host computer is to communicate with the development board controller 4 through the UART protocol, and send the motor control instructions of the rotating platform 2 to the development board controller 4, including forward rotation, reverse rotation and start measurement, etc. At the same time, the host computer also receives the distance information and angle information from the development board controller 4, and displays the data on the host computer.

[0108] The development board controller 4 is powered by a 5V power supply 5, communicates with the host computer using the UART serial port, receives control instructions from the host computer to control the rotating platform 2, and the development board controller 4 is connected to the displacement sensor 3 and the zero return sensor, and obtains the indication of the displacement sensor 3 and whether the zero return sensor is triggered in real time, and sends the distance information and the angle information of the rotating platform 2 to the host computer.

[0109] The displacement sensor 3 is powered by a 24V power supply 5, and its signal line is connected to the rotating platform 2, which is powered by a 24V power supply 5. The stepper motor drives the stepper motor, and the driver 6 drives the stepper motor. The driver 6 signal line is connected to the development board controller 4, receives the control instructions sent by the development board controller 4, realizes forward and reverse rotation and speed adjustment, and transmits distance information to the development board controller 4 in real time by sending analog voltage signals.

[0110] like Figure 7 As shown, the zero return sensor is powered by a 5V power supply 5, and its signal line is connected to the development board controller 4. When the zero return sensor is blocked, the information triggered by the zero return sensor is transmitted to the development board controller 4, and the development board controller 4 controls the motor to return to zero.

[0111] Optionally, the development board controller 4 receives data from the displacement sensor 3 through a signal line, and performs analog voltage signal processing on the data to obtain accurate distance information;

[0112] The rotating platform 2 is powered by a 24V power supply 5 and is driven to rotate by a stepper motor. The driver 6 drives the stepper motor. The driver 6 signal line is connected to the development board controller 4 and receives control instructions sent by the development board controller 4 to achieve forward and reverse rotation and speed adjustment.

[0113] Upload the accurate distance information to the host computer, and continuously send the rotation angle information to the host computer.

[0114] Example 3

[0115] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the following method:

[0116] Step 1: After startup, generate the control command of the rotating platform to drive the rotating platform to move, and start collecting sensor signals at the same time;

[0117] Step 2: Analyze the sensor signal in real time according to the set signal threshold, and obtain the refractive index of the sensor measurement point to determine whether the sensor's measurement position passes through an obstruction;

[0118] Step 3: If an obstruction is encountered, the distance and rotation angle difference between the sensor's measurement position and the two ends of the first obstruction are calculated based on the sensor signal; and as the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically; the measurement ends when the rotating platform rotates beyond 180°;

[0119] If there is no obstruction, the platform will continue to rotate until it exceeds 180° and the measurement ends;

[0120] Step 4: Substitute the distance between the two ends and the difference in rotation angle of each shielding object within the field of view of the agricultural machinery into the shielding shadow calculation model for calculation to obtain the shielding shadow chord length of each shielding object within the field of view of the agricultural machinery;

[0121] Step 5: Calculate the chord length of the shadows of all obstructions within the field of view of the agricultural machinery to obtain the average chord length of the shadows within the field of view of the agricultural machinery, which is used for the safety analysis of the forward field of view of the agricultural machinery driver.

[0122] In summary, compared with traditional measurement methods, this method can reduce the tediousness of manual measurement and does not require complex and precise field of view measurement equipment. It only requires the distance and rotation angle difference between the sensor measurement position and both ends of all obstructions to obtain the chord length of the shielding shadow of each obstruction, quickly obtain the agricultural machinery field of view measurement results, and generate a field of view safety assessment report. The field of view safety assessment report generates a table of obstruction measurement information parameters and a curve diagram of obstruction position distribution and size, which is used to provide reference data for optimizing the field of view.

[0123] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0124] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0125] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0126] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0127] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. A method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor, characterized in that: include: After power is supplied, a control command for the rotating platform is generated to drive the rotating platform to move, and sensor signals are obtained at the same time; The sensor signal is analyzed in real time according to the set signal threshold, and the value change of the sensor measurement point is obtained to determine whether the sensor's measurement position passes through an obstruction; If an obstruction is encountered, the distance and rotation angle difference between the sensor's measurement position and the two ends of the first obstruction are calculated based on the sensing signal; As the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are cyclically calculated; The measurement ends when the rotating platform rotates beyond 180°; If there is no obstruction, the platform will continue to rotate until it exceeds 180° and the measurement ends; Substitute the difference between the distance between the two ends and the rotation angle of each shielding object within the field of view of the agricultural machinery into the shielding shadow calculation model for calculation, and obtain the shielding shadow chord length of each shielding object within the field of view of the agricultural machinery; The chord lengths of shadows of all obstructions within the field of view of the agricultural machinery are calculated to obtain the average chord length of shadows within the field of view of the agricultural machinery, which is used for the safety analysis of the forward field of view of the agricultural machinery driver.

2. The method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor according to claim 1, characterized in that: The sensor signal is analyzed in real time according to the set signal threshold, and the value change of the sensor measurement point is obtained to determine whether the sensor's measurement position passes through an obstruction, including: By comparing the set signal threshold with the sensor signal, it is determined whether the sensor measurement position passes through an obstruction and the relative position change between the measurement position and the obstruction; Among them, if the sensor signal is greater than the set signal threshold, the sensor's measurement position is glass and no obstruction is encountered; If the sensor signal decreases from large to the set signal threshold, the sensor's measurement position moves from the side glass to one end of the obstruction and begins to encounter the obstruction; If the sensor signal increases from a small value to a large value above the set signal threshold, the measuring position of the sensor moves from the other end of the shielding object to the side glass and passes through the shielding object.

3. The method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor according to claim 1, characterized in that: If an obstruction is encountered, the distance and rotation angle difference between the sensor's measurement position and the two ends of the first obstruction are calculated based on the sensing signal; As the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are cyclically calculated; The measurement ends when the rotating platform rotates beyond 180°, including: When the measuring position of the sensor is from the side glass to one end of the shielding object, the distance and rotation angle between the measuring position of the sensor and one end of the shielding object are calculated according to the sensor signal; When the measuring position of the sensor moves from the other end of the shielding object to the side glass, the distance and the rotation angle difference between the measuring position of the sensor and the other end of the shielding object are calculated according to the sensor signal; As the rotating platform rotates, the distance and rotation angle difference between the sensor's measurement position and the two ends of other obstructions are calculated cyclically to obtain the distance and rotation angle difference between the two ends of each obstruction within the field of view of the agricultural machinery, until the measurement is terminated when the rotating platform rotates more than 180°.

4. The method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor according to claim 1, characterized in that: It also includes performing data point curve fitting on the sensor signal after the measurement is completed to obtain a fitting curve of the measurement data point; Find the data points associated with the sawtooth curve from the fitting curve and define them as invalid data; Filter invalid data to obtain valid data; Based on the valid data, the difference between the distance between the two ends and the rotation angle of each shielding object is re-find.

5. The method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor according to claim 1, characterized in that: The expression of the occlusion shadow calculation model is:

6. In the formula, is the position of the displacement sensor, They are the two ends of the shadow chord length, is the chord length of the shadow of the obstruction, is the distance from one end of the shadow chord to the displacement sensor, is the distance from the other end of the shadow chord to the displacement sensor, It is the difference between the angles between the two ends of the shadow chord and the displacement sensor, that is, the rotation angle.

7. The method for measuring the front visual field of an agricultural machine driver based on a displacement sensor according to claim 1, characterized in that: The chord lengths of the shadows of all obstructions within the field of view of the agricultural machinery are calculated to obtain the average chord lengths of the shadows within the field of view of the agricultural machinery, including: The number and position distribution of shadows of all obstructions within the field of view of the agricultural machinery are counted to obtain other field of view data of the obstructions.

8. The method for measuring the front visual field of an agricultural machine driver based on a displacement sensor according to claim 5, characterized in that: The safety analysis of the agricultural machinery driver's front vision also includes: If the mean chord length of the shadows within the agricultural machinery field of view meets the preset agricultural machinery field of view quality threshold, the agricultural machinery field of view safety measurement result is obtained; If the mean chord length of the obstructed shadow within the field of view of the agricultural machinery does not meet the preset agricultural machinery field of view quality threshold, an unsafe measurement result of the agricultural machinery field of view is obtained, and a parameter table of obstruction measurement information is generated and a curve diagram is drawn based on the valid data to provide reference data for optimizing the field of view.

9. A displacement sensor-based agricultural machinery driver's front field measurement system, characterized in that: include: Host computer, rotating platform, displacement sensor and development board controller; The driving motor of the rotating platform is electrically connected to the upper computer and is used to generate a control instruction for the rotating platform to drive the rotating platform to move; The displacement sensor is mounted on the rotating platform and is electrically connected to the development board controller; The host computer communicates with the development board controller via the UART protocol, receives the signal fed back by the sensor and executes the steps of the method according to any one of claims 1 to 7.

10. The agricultural machinery driver's front visual field measurement system based on displacement sensor according to claim 8 is characterized in that: The displacement sensor is installed 670 mm above the agricultural machinery seat and is located 10 mm in front of the seat; the measurement distance of the displacement sensor is 0.2-7 m.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for measuring the front visual field of an agricultural machinery driver based on a displacement sensor as described in any one of claims 1 to 7 are implemented.

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