Agricultural machine and anti-tipping method, controller, system and medium thereof

Abstract

The invention discloses an agricultural machine, an anti-rollover method thereof, a controller, a system and a medium. The method comprises the following steps: estimating a predicted roll angle after a set prediction time according to a roll angle, a roll angle speed and a roll angle acceleration in a set period; determining whether a tipping risk exists or not according to a comparison result of a larger value in the current side tipping angle and the predicted side tipping angle and a set angle threshold value and a comparison result of a current transverse load transfer rate of the agricultural machine and a set transfer rate threshold value; and determining rollover risk levels, and executing a preset active anti-rollover control strategy by adapting to different rollover risk levels. The invention provides a roll angle prediction algorithm for agricultural machinery, and further provides an active anti-rollover control strategy suitable for different rollover risk levels, so that the rollover risk caused by sensor data hysteresis can be effectively prevented.

Description

Technical Field

[0001] The present application relates to the technical field of agricultural machinery, and in particular to an agricultural machinery and an anti-rollover method, controller, system and medium thereof. Background Art

[0002] At present, agricultural machinery with a wire-controlled chassis, such as tractors, is widely used in hilly and mountainous areas because of its chassis' advantages of fast response, wide speed regulation range, forward and reverse rotation, and feedback braking. However, when agricultural machinery is operating in hilly and mountainous areas, the slope is large, which makes the vehicle roll angle large. When the vehicle is driving sideways on the slope, the pressure on the upper wheel will be reduced compared to that on flat ground. The greater the vehicle roll angle, the smaller the upper wheel pressure, so the center of gravity shifts, and the risk of rollover and instability increases.

[0003] Practice has shown that even if tractors and other equipment are equipped with rollover protection structures that meet the standards, the driver may still be injured when a rollover occurs. In order to reduce the incidence of accidents and improve the safety of the entire driving and operating process in hilly and mountainous areas, it is not enough to take only passive safety measures (safety frames, etc.). It is necessary to study the early warning of rollover risks and active control to prevent rollovers.

[0004] However, currently in the field of agricultural machinery in hilly and mountainous areas, active anti-rollover measures are generally to reduce the tilt angle of the vehicle body on the slope by adding mechanical structures, such as active anti-rollover bars, active and semi-active suspensions, etc., to reduce the risk of rollover, but cannot prevent the risk of rollover. In addition, the prior art also involves active anti-rollover measures that use angle sensors to detect the roll angle in real time, but the sensor data usually has a lag and cannot effectively prevent the risk of rollover. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide an agricultural machinery and its anti-rollover method, controller, system and medium, so as to at least partially solve the above-mentioned technical problems.

[0006] In order to achieve the above-mentioned purpose, the first aspect of the present application provides an anti-rollover method for agricultural machinery, including: estimating the predicted roll angle after a set prediction time based on the roll angle, roll angle velocity and roll angle acceleration of the agricultural machinery within a set period; determining whether there is a rollover risk based on the comparison result of the larger value of the current roll angle and the predicted roll angle with the set angle threshold, and based on the comparison result of the current lateral load transfer rate of the agricultural machinery with the set transfer rate threshold; and in the case of determining that the rollover risk exists, determining the rollover risk level, and executing a preset active anti-rollover control strategy adapted to different rollover risk levels.

[0007] In the embodiment of the present application, according to the roll angle, roll angle velocity and roll angle acceleration of the agricultural machinery within a set period, estimating the predicted roll angle after the set prediction time includes: obtaining an average value of multiple groups of roll angle values ​​within the set period as an initial predicted value θ of the roll angle 0 ; performing differential processing on the multiple groups of roll angle values ​​to obtain corresponding multiple groups of roll angular velocity values, and obtaining the average value of the multiple groups of roll angular velocity values ​​as the initial predicted value of the roll angular velocity ω 0 ; performing differential processing on the multiple groups of roll angular velocity values ​​to obtain corresponding multiple groups of roll angular acceleration values, and obtaining the average value of the multiple groups of roll angular acceleration values ​​as the initial predicted value a of the roll angular acceleration 0 ; and the predicted roll angle θ is calculated using the following formula:

[0008] θ=θ 0 +ω 0 T+0.5a 0 T 2

[0009] Wherein, T is the predicted time.

[0010] In the embodiment of the present application, before determining whether there is a rollover risk, the anti-rollover method further includes calculating the current lateral load transfer rate by the following formula:

[0011]

[0012] Wherein, LTR is the current lateral load transfer rate, a y is the lateral acceleration at the center of gravity of the agricultural machinery, B 2 is the wheelbase of the agricultural machinery, h is the height of the center of mass of the agricultural machinery, and g is the acceleration due to gravity.

[0013] In an embodiment of the present application, determining whether there is a rollover risk includes determining that the agricultural machinery does not have a rollover risk when any one of the following conditions is met, otherwise determining that the agricultural machinery has a rollover risk and determining the rollover risk level: a first condition, whether the larger value of the current roll angle and the predicted roll angle is less than a first set roll angle threshold; and a second condition, whether the current lateral load transfer rate is less than a first set transfer rate threshold.

[0014] In an embodiment of the present application, determining the rollover risk level includes: when the larger value of the current roll angle and the predicted roll angle is greater than or equal to the first set roll angle threshold and less than the second set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the first set transfer rate threshold and less than the second set transfer rate threshold, determining the rollover risk level to be a first-level rollover risk; when the larger value of the current roll angle and the predicted roll angle is greater than or equal to the second set roll angle threshold and less than a third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the second set transfer rate threshold and less than the third set transfer rate threshold, determining the rollover risk level to be a second-level rollover risk; and when the larger value of the current roll angle and the predicted roll angle is greater than or equal to the third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the third set transfer rate threshold, determining the rollover risk level to be a third-level rollover risk. Among them, the first set roll angle threshold, the second set roll angle threshold and the third set roll angle threshold increase successively, the first set transfer rate threshold, the second set transfer rate threshold and the third set transfer rate threshold increase successively, and the risk levels of the first level rollover risk, the second level rollover risk and the third level rollover risk increase successively.

[0015] In an embodiment of the present application, the first set roll angle threshold is the normal roll angle allowed for the agricultural machinery during operation, and the second set roll angle threshold and the third set roll angle threshold are set in association with the extreme roll angle of the agricultural machinery and the normal roll angle.

[0016] In the embodiment of the present application, the limit roll angle is determined by the following formula:

[0017]

[0018] Among them, β MAX is the limit roll angle, A y is the stabilizing lever arm, h is the height of the center of mass of the agricultural machinery, v is the vehicle speed, and R is the turning radius.

[0019] In an embodiment of the present application, determining the rollover risk level also includes: for the determined first-level rollover risk or second-level rollover risk, detecting whether there is driver operation information associated with a decrease in the rollover angle within a specified time, and if not, upgrading the corresponding rollover risk to the next level.

[0020] In an embodiment of the present application, the preset active anti-rollover control strategy adapted to different rollover risk levels includes: for the first level rollover risk, controlling the instrument of the agricultural machinery to give an alarm; for the second level rollover risk, controlling the instrument of the agricultural machinery to give an alarm, and limiting the turning of the agricultural machinery in the direction of increasing the roll angle, and limiting the increase in the walking torque of the agricultural machinery; and for the third level rollover risk, controlling the instrument of the agricultural machinery to give an alarm, braking the agricultural machinery, and controlling the agricultural machinery to turn in the opposite direction of increasing the roll angle.

[0021] The second aspect of the present application provides an anti-rollover controller for agricultural machinery, comprising: a memory configured to store instructions; and a processor configured to call the instructions from the memory and to implement any of the above-mentioned anti-rollover methods for agricultural machinery when executing the instructions.

[0022] The third aspect of the present application provides an anti-rollover system for agricultural machinery, comprising: a signal input module for acquiring the driving parameters of the agricultural machinery; any of the above-mentioned anti-rollover controllers, for executing the anti-rollover method according to the driving parameters to generate corresponding control instructions; and an output control module, for performing anti-rollover alarm and anti-rollover active control according to the control instructions of the anti-rollover controller.

[0023] A fourth aspect of the present application provides an agricultural machine, comprising the above-mentioned anti-rollover system.

[0024] A fifth aspect of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute any one of the above-described methods for preventing rollover of agricultural machinery.

[0025] Through the above technical scheme, the embodiment of the present application proposes a roll angle prediction algorithm for agricultural machinery, and further proposes an active anti-rollover control strategy adapted to different rollover risk levels, which can effectively prevent the rollover risk caused by the lag of sensor data.

[0026] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

[0028] Figure 1 A schematic diagram of a process flow of an anti-rollover method for agricultural machinery according to an embodiment of the present application is schematically shown;

[0029] Figure 2 An example anti-rollover risk level process according to an embodiment of the present application is schematically shown;

[0030] Figure 3 A structural block diagram of an anti-rollover controller for agricultural machinery according to an embodiment of the present application is schematically shown; and

[0031] Figure 4 The structural block diagram of an anti-rollover system for agricultural machinery according to an embodiment of the present application is schematically shown.

[0032] Description of Reference Numerals

[0033] 100 Signal input module 200 Anti-tilt controller

[0034] 300 Output Control Module DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0036] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0037] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0038] Figure 1 The flowchart of an anti-rollover method for agricultural machinery according to an embodiment of the present application is schematically shown. Figure 1As shown, an embodiment of the present application provides an anti-rollover method for agricultural machinery. The method is, for example, executed by a vehicle control unit (VCU) of the agricultural machinery and may include the following steps S100-S300.

[0039] Step S100 , estimating a predicted roll angle after a set prediction time according to the roll angle, roll angle velocity and roll angle acceleration of the agricultural machinery within a set period.

[0040] That is, step S100 provides a roll angle prediction algorithm executed by the VCU. In the example, the implementation of the roll angle prediction algorithm includes:

[0041] 1) Basic idea: Assume that the VCU processing cycle is 10ms, the cycle time of the roll angle prediction algorithm is 50ms, and the 5 sets of roll angles θ within 50ms are used. i , construct the roll angle θ-time function, then perform differential processing on the function to obtain the angular velocity ω-time function, perform second-order differential processing on the function to further obtain the angular acceleration a-time function, and finally obtain the roll angular velocity ω and roll angular acceleration a at each moment; further calculate the average roll angle, average roll angular velocity, and average roll angular acceleration within the processing cycle to predict the roll angle of the next cycle.

[0042] 2) Algorithm derivation process: Use the body tilt sensor to collect the roll angle, and record the collected data points as (θ 1 ,t 1 ),(θ 2 ,t 2 ),(θ 3 ,t 3 )…,θ i represents the roll angle collected at the i-th time, t i is the corresponding acquisition time. For the acquired data points, the roll angle θ-time function is differentiated to obtain the angular velocity ω-time function:

[0043]

[0044] Where Δt is t i -t i-1 .

[0045] Further differentiation of the angular velocity ω-time function yields the angular acceleration a-time function as follows:

[0046] a i =ω i -ω i-1

[0047] Thus, following the example in the basic idea, in each processing cycle of the VCU, there are 5 sets of roll angle data, 4 sets of roll angle velocity data, and 3 sets of roll angle acceleration data. The average value of these data is taken to obtain the initial predicted value θ of the roll angle used for angle prediction. 0 , initial predicted value of roll angular velocity ω 0 and the initial predicted value of the roll angular acceleration a 0 .

[0048] Furthermore, assuming that the roll acceleration of the agricultural machinery will not change in the next period of time, taking the current operating state of the vehicle as the initial value, the predicted roll angle θ after the predicted time T under the condition of maintaining the current roll acceleration can be calculated according to the following formula:

[0049] θ=θ 0 +ω 0 T+0.5a 0 T 2

[0050] Wherein, θ is the predicted roll angle; θ 0 ,ω 0 、a 0 As mentioned above, they are respectively the initial predicted value of the roll angle, the initial predicted value of the roll angular velocity and the initial predicted value of the roll angular acceleration obtained by calculation; and T is the predicted time.

[0051] Among them, the prediction time T can be determined in combination with the driver's experience and the vehicle's condition. Generally, the driver's reaction time after receiving the warning information (instrument display) is 0.4-1.5s; the sum of the time from the accelerator pedal to the brake pedal after reaction and the braking effect time is generally 0.2-0.5s; in addition, considering the vehicle speed reduction time and the actual computing power of the vehicle controller, the prediction period T is set to 3s, that is, the embodiment of the present application can calculate the predicted value of the roll angle after 3s in real time.

[0052] Step S200, determines whether there is a rollover risk based on the comparison result of the larger value of the current roll angle and the predicted roll angle with the set angle threshold, and based on the comparison result of the current lateral load transfer rate (Lateral Load Transfer Ratio, LTR for short) of the agricultural machinery with the set transfer rate threshold.

[0053] In the embodiment of the present application, before determining whether there is a risk of rollover, the current lateral load transfer rate is calculated by the following formula:

[0054]

[0055] Wherein, LTR is the current lateral load transfer rate; ay is the lateral acceleration at the center of gravity of the agricultural machinery, which can be obtained by reading the Z-axis acceleration data of the inclination sensor; B 2 is the wheelbase of the agricultural machinery; h is the height of the center of mass of the agricultural machinery, and its size changes linearly with the roll angle of the vehicle; g is the acceleration due to gravity.

[0056] Further, for step S200, determining whether there is a rollover risk includes: if any one of the following first conditions and second conditions is met, determining that the agricultural machinery does not have a rollover risk; otherwise, determining that the agricultural machinery has a rollover risk.

[0057] The first condition is whether a larger value between the current roll angle and the predicted roll angle is smaller than a first set roll angle threshold.

[0058] The second condition is whether the current lateral load transfer rate is less than a first set transfer rate threshold.

[0059] Step S300: when it is determined that the rollover risk exists, the rollover risk level is determined, and a preset active anti-rollover control strategy is executed according to different rollover risk levels.

[0060] In the embodiment of the present application, corresponding to the first condition and the second condition mentioned above, determining the rollover risk level may include the following three-level determination steps, wherein for ease of description, the larger value of the current roll angle and the predicted roll angle is recorded as the maximum roll angle value:

[0061] Determine the first-level rollover risk: when the maximum roll angle value is greater than or equal to the first set roll angle threshold and less than the second set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the first set transfer rate threshold and less than the second set transfer rate threshold, determine that the rollover risk level is a first-level rollover risk.

[0062] Determine the secondary rollover risk: when the maximum roll angle value is greater than or equal to the second set roll angle threshold and less than the third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the second set transfer rate threshold and less than the third set transfer rate threshold, determine that the rollover risk level is the secondary rollover risk.

[0063] Determine a third level of rollover risk. When the maximum roll angle value is greater than or equal to the third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the third set transfer rate threshold, determine that the rollover risk level is a third level of rollover risk.

[0064] Among them, the first set roll angle threshold, the second set roll angle threshold and the third set roll angle threshold increase successively, the first set transfer rate threshold, the second set transfer rate threshold and the third set transfer rate threshold increase successively, and the risk levels of the first level rollover risk, the second level rollover risk and the third level rollover risk increase successively.

[0065] And, more preferably, the first set roll angle threshold is the normal roll angle allowed by the agricultural machinery during operation, and the second set roll angle threshold and the third set roll angle threshold are set in association with the extreme roll angle of the agricultural machinery and the normal roll angle.

[0066] And, more preferably, the determining of the rollover risk level also includes: for the determined first-level rollover risk or second-level rollover risk, detecting whether there is driver operation information associated with a decrease in the rollover angle within a specified time, and if not, upgrading the corresponding rollover risk to the next level.

[0067] After determining the rollover risk level, executing a preset active anti-rollover control strategy adapted to different rollover risk levels in step S300 may include: for the first level rollover risk, controlling the instrument of the agricultural machinery to give an alarm; for the second level rollover risk, controlling the instrument of the agricultural machinery to give an alarm, and limiting the turning of the agricultural machinery in the direction of increasing the roll angle, and limiting the increase in the walking torque of the agricultural machinery; and for the third level rollover risk, controlling the instrument of the agricultural machinery to give an alarm, braking the agricultural machinery, and controlling the agricultural machinery to turn in the opposite direction of increasing the roll angle.

[0068] Regarding the above-mentioned active anti-rollover control strategy, for example, when it is executed by a tractor with a drive-by-wire chassis (i.e., including five major systems: drive-by-wire steering, drive-by-wire braking system, drive-by-wire shifting, drive-by-wire accelerator pedal and drive-by-wire suspension), the VCU directly controls the drive-by-wire chassis, and then, through the advantages of the drive-by-wire chassis, it can quickly and actively avoid the risk of rollover.

[0069] The following is a detailed description of the implementation of the anti-rollover method for agricultural machinery in the embodiment of the present application with reference to examples. Figure 2 The example anti-rollover risk level process according to the embodiment of the present application is schematically shown. In this example, a tractor with a wire-controlled chassis (such as a wheel-track compound tractor) is taken as an example, and the first set roll angle threshold, the second set roll angle threshold and the third set roll angle threshold are θ respectively. 01 ,θ 12 and θ 23 , assuming that the first set transfer rate threshold, the second set transfer rate threshold and the third set transfer rate threshold are L01 , L 12 and L 23 And, corresponding to the third level of rollover risk, the corresponding threshold value range is shown in Table 1 below:

[0070] Table 1 Schematic diagram of roll angle and LTR boundary

[0071]

[0072] The relevant parameters in Table 1 can also be understood in conjunction with the example description below, and will not be described in detail here.

[0073] like Figure 2 As shown, the anti-tilt gravity in the example may include the following steps:

[0074] Step S1, obtaining sensor signals.

[0075] The sensor signal includes the roll angle collected by the vehicle body tilt sensor.

[0076] Step S2, calculate the current lateral load transfer rate LTR, and calculate the predicted roll angle after the predicted time, and determine the larger value of the current roll angle and the predicted roll angle, which is recorded as the maximum roll angle value θ max .

[0077] For example, the prediction time is 3s, the method in step S100 is used to obtain the predicted roll angle θ, and θ is determined to be the maximum roll angle value θ max .

[0078] Step S3, determining the maximum roll angle value θ max Is it less than the first set roll angle threshold θ 01 , that is, θ max <θ 01 , or whether the current lateral load transfer rate LTR is less than the first set transfer rate threshold L 01 , that is, LTR <L 01 If so, return to step S2, otherwise execute step S4.

[0079] For example, the slope of a general tractor when operating horizontally on hills, mountains, and slopes does not exceed 15°, that is, the vehicle can operate horizontally and stably on a 15° slope. Further considering the normal angle fluctuation during the operation, the first set roll angle threshold θ can be set 01 is 18° (as shown in Table 1), so that at the maximum roll angle value θ max Greater than or equal to θ 01 =18°, the tipping warning function is activated. In addition, the first setting transfer rate threshold L 01It can be set to 0.6 based on practical experience (as shown in Table 1).

[0080] Step S4, determine whether the maximum roll angle value is θ max Less than the second set roll angle threshold θ 12 , that is, θ max <θ 12 , or whether the current lateral load transfer rate LTR is less than the second set transfer rate threshold L 12 , that is, LTR <L 12 If so, it is determined to be a level one rollover risk and step S6 is executed, otherwise, step S5 is continued.

[0081] Step S5, determine whether the maximum roll angle value is θ max Less than the third set roll angle threshold θ 23 , that is, θ max <θ 23 , or whether the current lateral load transfer rate LTR is less than the third set transfer rate threshold L 23 , that is, LTR <L 23 If so, it is determined as a second-level rollover risk, otherwise it is determined as a third-level rollover risk.

[0082] For steps S4 and S5, for example, the second set roll angle threshold θ can be calculated using the following formula: 12 and the third set roll angle threshold θ 23 :

[0083] θ 23 =β MAX -Δθ

[0084]

[0085] Among them, β MAX It refers to the limit roll angle. When the vehicle roll angle exceeds the limit roll angle, the vehicle will roll over. Δθ is the preset fluctuation value, for example, 3°. θ 01 As described above, it is, for example, 18°.

[0086] Furthermore, since the body posture of the wire-controlled chassis can be flexibly changed, its roll angle is related to the vehicle speed, turning radius, etc. Accordingly, for example, the limit roll angle β MAX It is determined by the following formula:

[0087]

[0088] Among them, A y is the stabilizing force arm, h is the height of the center of mass, v is the vehicle speed, and R is the turning radius.

[0089] Furthermore, regarding the stabilizing arm Ay ,exist:

[0090]

[0091] Among them, B 1 is the front wheel track width of the all-wheel tractor (equivalent to the front track width in a wheel-track tractor), B 2 is the rear wheel track, L is the wheelbase, and a is the x-axis center of mass.

[0092] Thus, this example can calculate β in real time based on the input parameters of the tractor. MAX , in order to achieve the purpose of accurate early warning and control.

[0093] In addition, for step S4 and step S5, as shown in Table 1, the second setting transfer rate threshold L 12 For example, take 0.8, and the third setting transfer rate threshold L 23 For example, take 1.

[0094] Step S6, for the first level rollover risk, whether the driver responds to the warning within the specified time, if yes, return to step S2, otherwise upgrade to the second level rollover risk.

[0095] For example, the specified time is 5s, and the same upgrade process is performed for the second-level rollover risk. In this way, the driver can be prevented from further increasing the rollover risk due to ignoring the anti-rollover warning information issued by the instrument during driving. For example, when the rollover warning for the corresponding level of rollover risk is issued, the driving response timing is performed. If the system does not detect the driver's effective driving operation within 5s to stop the roll angle from increasing or decreasing, the system will automatically upgrade the rollover risk level to strengthen the reminder.

[0096] In combination with the relevant parameters of the examples given above, the vehicle-mounted VCU may, for example, execute Table 2 to implement the active anti-rollover control strategy in a hierarchical manner.

[0097] Table 2 Hierarchical anti-rollover control strategy

[0098]

[0099] Among them, the first-level active anti-rollover control response includes: limiting the turning of the agricultural machinery in the direction of increasing the roll angle; and limiting the increase of the walking torque of the agricultural machinery.

[0100] Among them, the secondary active anti-rollover control response includes: braking the agricultural machinery; and controlling the agricultural machinery to turn in the opposite direction to increase the roll angle.

[0101] That is, when the rollover risk reaches level two and level three, the system will correspondingly initiate two levels of active anti-rollover control response to actively control the vehicle to varying degrees.

[0102] In addition, it should be noted that although the three levels of rollover risk all involve rollover warnings through the instrument, the specific prompting schemes may be different. For example, according to the degree of rollover risk, different font sizes, colors and / or contents may be used to warn the driver to different degrees at different display positions on the instrument, as shown in Table 3:

[0103] Table 3 Warning examples

[0104]

[0105] In the example, in addition to the instrument reminder, the buzzer alarm can also be driven to issue alarms of different frequencies according to different rollover risk levels. In addition, since the active anti-rollover control strategy will actively intervene in vehicle driving, there is a situation that violates the driver's driving intention, so the "manually closed" function can be set on the instrument to set whether to turn on the anti-rollover function through the instrument configuration item.

[0106] In summary, the anti-rollover method for agricultural machinery of the embodiment of the present application has at least the following advantages:

[0107] 1. The embodiment of the present application proposes a roll angle prediction algorithm for agricultural machinery, and further proposes an active anti-rollover control strategy adapted to different rollover risk levels, which can effectively prevent the rollover risk caused by the lag of sensor data.

[0108] 2. The roll angle prediction algorithm of the embodiment of the present application introduces the roll angle acceleration dimension, which can more accurately judge the angle change trend and can be applied to agricultural machinery operations in hilly and mountainous scenes with complex and changeable working conditions.

[0109] 3. The method for calculating the lateral load transfer rate in the roll angle prediction algorithm of the embodiment of the present application does not rely on the pressure sensor data, thereby reducing the calculation error caused by, for example, a thin film pressure sensor that is only applicable to track pressure measurement but not tire pressure measurement.

[0110] 4. In the roll angle prediction algorithm of the embodiment of the present application, the maximum roll angle is calculated in real time according to the posture and driving parameters of the agricultural machinery, and the relevant roll angle threshold is adjusted and updated in real time accordingly. It has a good anti-rollover effect for agricultural machinery that is suitable for hilly and mountainous scenes, has adjustable posture, large center of mass changes, and very complex driving conditions.

[0111] 5. The anti-rollover method of the embodiment of the present application is applicable to agricultural machinery based on a wire-controlled chassis. The chassis can be completely controlled by the VCU of the agricultural machinery, and in an emergency, the tractor's roll angle can be actively controlled to continue to increase, thereby achieving active safety protection for the driver and improving driving safety and driver experience.

[0112] Figure 3 The structure block diagram of an anti-rollover controller for agricultural machinery according to an embodiment of the present application is schematically shown. Figure 3 As shown, the anti-rollover controller may include: a memory configured to store instructions; and a processor configured to call the instructions from the memory and implement any of the above anti-rollover methods when executing the instructions.

[0113] The anti-rollover controller may be a VCU of an agricultural machine or a controller configured separately. In addition, details of the anti-rollover controller for implementing anti-rollover control may refer to the aforementioned embodiments.

[0114] Figure 4 The structure block diagram of an anti-rollover system for agricultural machinery according to an embodiment of the present application is schematically shown. Figure 4 As shown, the anti-rollover system includes: a signal input module 100, used to obtain the driving parameters of the agricultural machinery; the above-mentioned anti-rollover controller 200, used to execute the anti-rollover method according to the driving parameters to generate corresponding control instructions; and an output control module 300, used to perform anti-rollover alarm and anti-rollover active control according to the control instructions of the anti-rollover controller.

[0115] In the example, the signal input module 100 includes but is not limited to a vehicle body inclination sensor, a steering wheel angle sensor, a throttle depth sensor, a brake depth sensor, a drive wheel angle sensor, etc. In practical applications, a vehicle body inclination sensor is set at the horizontal position of the tractor frame, a drive wheel angle sensor is set at the drive wheel axle position, and a steering wheel angle sensor, a throttle depth sensor, and a brake depth sensor are set in the corresponding mechanical structure. The output of these sensor signals is connected to the vehicle controller VCU, and parameter information is sent to the VCU in real time. In addition, each travel motor controller sends motor operation data, including a speed signal, through the bus, so that the VCU reads the speed signal from the bus for processing.

[0116] The anti-rollover controller 200 is, for example, a VCU. The signal input module 100 collects various driving parameters of the tractor during driving and sends them to the VCU. The VCU, as a signal processing center of driving data, is adapted to the requirements of the above anti-rollover method and can be configured with at least the following functions:

[0117] 1) Obtain the current sensor analog signals such as roll angle, steering wheel angle, throttle depth, brake depth and drive wheel angle, and convert them into processable data values ​​through the ADC module.

[0118] 2) Read the current wheel motor speed information of the vehicle in the CAN bus and convert it into the tractor's driving speed, thus completing the vehicle speed value calculation.

[0119] 3) Determine whether the vehicle roll angle is greater than the safety threshold, predict the roll angle change trend, etc. This process includes calculating the limit rollover angle in the current state based on steering, vehicle speed, and vehicle posture information.

[0120] 4) Control the instrument and buzzer to output warning signals, and actively control the vehicle travel system. This process includes outputting corresponding sound and light alarm signals and travel system control signals according to the above-mentioned anti-rollover graded processing method based on the current roll angle, predicted roll angle, and LTR value.

[0121] Adapting to the above-mentioned VCU function, the output control module 300 includes, for example, a steering system, a travel system, an instrument display system, and a buzzer, etc. For example, according to the rollover warning information issued by the VCU, a sound and light combined alarm method is adopted, the instrument on the driving platform displays alarm prompts of different colors and sizes to the driver, the buzzer emits alarm sounds of different frequencies according to different warning levels, and the travel and steering systems respond to the active control request of the VCU, and according to the different rollover risk levels calculated by the VCU, the tractor is actively controlled with different logics.

[0122] It should be noted that the process of VCU realizing anti-rollover warning and active anti-rollover control is as mentioned above. Figure 2 As shown, no further description will be given here.

[0123] In an embodiment of the present application, an agricultural machine is provided, which includes the above anti-rollover system. The agricultural machine has a wire-controlled chassis, which can fully utilize the advantages of the wire-controlled chassis for electronic control of the vehicle's walking, steering, etc. instead of mechanical control to implement the above anti-rollover system.

[0124] The anti-rollover scheme of the embodiment of the present application is particularly applicable to hybrid tractors and pure electric tractors for hilly and mountainous areas, but it can be understood that the embodiment of the present application is not limited to this type of tractor, and can also be partially or completely applied to other tractors or harvesters.

[0125] An embodiment of the present application also provides a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute the above-mentioned anti-rollover method for agricultural machinery.

[0126] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt 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.) that contain computer-usable program code.

[0127] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes 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 generate 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.

[0128] 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.

[0129] 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 The steps for the functions specified in one or more boxes.

[0130] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0131] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0132] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0133] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0134] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for preventing overturning of agricultural machinery, characterized in that: include: estimating a predicted roll angle after a set prediction time according to the roll angle, roll angle velocity and roll angle acceleration of the agricultural machinery within a set period; Determining whether there is a rollover risk based on a comparison result of a larger value of a current roll angle and the predicted roll angle with a set angle threshold, and based on a comparison result of a current lateral load transfer rate of the agricultural machinery with a set transfer rate threshold; as well as When it is determined that the rollover risk exists, the rollover risk level is determined, and a preset active anti-rollover control strategy is executed according to different rollover risk levels.

2. The anti-rollover method according to claim 1, characterized in that: According to the roll angle, roll angle velocity and roll angle acceleration of the agricultural machinery within a set period, estimating a predicted roll angle after a set prediction time includes: Obtaining an average value of the plurality of groups of roll angle values ​​within the set period as an initial predicted roll angle value θ0; Performing differential processing on the multiple groups of roll angle values ​​to obtain corresponding multiple groups of roll angular velocity values, and obtaining an average value of the multiple groups of roll angular velocity values ​​as an initial predicted value ω0 of the roll angular velocity; Performing differential processing on the multiple groups of roll angular velocity values ​​to obtain corresponding multiple groups of roll angular acceleration values, and obtaining an average value of the multiple groups of roll angular acceleration values ​​as an initial predicted value a0 of the roll angular acceleration; and The predicted roll angle θ is calculated using the following formula: θ=θ0+ω0T+0.5a0T 2 Wherein, T is the predicted time.

3. The anti-rollover method according to claim 1, characterized in that: Before determining whether there is a rollover risk, the anti-rollover method further includes calculating the current lateral load transfer rate by the following formula: Wherein, LTR is the current lateral load transfer rate, a y is the lateral acceleration at the center of gravity of the agricultural machinery, B2 is the wheelbase of the agricultural machinery, h is the height of the center of mass of the agricultural machinery, and g is the acceleration due to gravity.

4. The anti-rollover method according to claim 1, characterized in that: Determining whether there is a risk of tipping over includes: If any one of the following conditions is met, it is determined that the agricultural machinery does not have a risk of tipping over; otherwise, it is determined that the agricultural machinery has a risk of tipping over, and the tipping risk level is determined: A first condition: whether the larger value of the current roll angle and the predicted roll angle is less than a first set roll angle threshold; and The second condition is whether the current lateral load transfer rate is less than a first set transfer rate threshold.

5. The anti-rollover method according to claim 4, characterized in that: Determining the tipping risk level includes: When the larger value of the current roll angle and the predicted roll angle is greater than or equal to the first set roll angle threshold and less than the second set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the first set transfer rate threshold and less than the second set transfer rate threshold, the rollover risk level is determined to be a first-level rollover risk; When the larger value of the current roll angle and the predicted roll angle is greater than or equal to the second set roll angle threshold and less than the third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the second set transfer rate threshold and less than the third set transfer rate threshold, determining that the rollover risk level is a second-level rollover risk; and When the larger value of the current roll angle and the predicted roll angle is greater than or equal to the third set roll angle threshold, or the current lateral load transfer rate is greater than or equal to the third set transfer rate threshold, determining that the rollover risk level is a third-level rollover risk; Among them, the first set roll angle threshold, the second set roll angle threshold and the third set roll angle threshold increase successively, the first set transfer rate threshold, the second set transfer rate threshold and the third set transfer rate threshold increase successively, and the risk levels of the first level rollover risk, the second level rollover risk and the third level rollover risk increase successively.

6. The anti-rollover method according to claim 5, characterized in that: The first set roll angle threshold is a normal roll angle allowed for the agricultural machine during operation, and the second set roll angle threshold and the third set roll angle threshold are set in association with the limit roll angle of the agricultural machine and the normal roll angle.

7. The anti-rollover method according to claim 6, characterized in that: The limit roll angle is determined by the following formula: Among them, β MAX is the limit roll angle, A y is the stabilizing force arm, h is the height of the center of mass of the agricultural machinery, v is the vehicle speed, and R is the turning radius.

8. The anti-rollover method according to claim 5, characterized in that: Determining the tipping risk level further includes: For the determined first-level rollover risk or second-level rollover risk, it is detected whether there is driver operation information associated with a decrease in the rollover angle within a specified time. If not, the corresponding rollover risk is upgraded to the next level.

9. The anti-rollover method according to claim 5, characterized in that: The preset active anti-rollover control strategy adapted to different rollover risk levels includes: In response to the first-level tipping risk, controlling an instrument of the agricultural machinery to sound an alarm; In response to the secondary rollover risk, controlling the instrument of the agricultural machinery to give an alarm, limiting the turning of the agricultural machinery in the direction of increasing the roll angle, and limiting the increase of the travel torque of the agricultural machinery; and In response to the third level rollover risk, the instrument of the agricultural machinery is controlled to sound an alarm, the agricultural machinery is braked, and the agricultural machinery is controlled to turn in the opposite direction to increase the roll angle.

10. An anti-rollover controller for agricultural machinery, characterized in that: include: a memory configured to store instructions; as well as A processor is configured to call instructions from the memory and implement the anti-rollover method for agricultural machinery according to any one of claims 1 to 9 when executing the instructions.

11. An anti-rollover system for agricultural machinery, characterized in that: include: A signal input module, used to obtain the driving parameters of the agricultural machinery; The anti-rollover controller of claim 10, configured to execute the anti-rollover method to generate corresponding control instructions according to the driving parameters; as well as The output control module is used to perform anti-rollover alarm and anti-rollover active control according to the control instructions of the anti-rollover controller.

12. An agricultural machine, characterized in that: Includes the anti-tipping system as claimed in claim 11.

13. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions for causing the machine to execute the anti-rollover method for agricultural machinery according to any one of claims 1 to 9.

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