阅读说明：本技术 推土机转向控制方法和系统 (Bulldozer steering control method and system ) 是由 龚纪强 于 2020-06-30 设计创作，主要内容包括：本发明提供了一种推土机转向控制方法和系统,其中,所述方法包括：获取推土机的转向模式；获取推土机的转向控制指令和发动机转速；根据转向模式、转向控制指令和发动机转速得到推土机的目标转向速度；获取推土机的负载压力以及负载压力作用下的实际转向速度；根据目标转向速度和实际转向速度得到推土机的转向速度差值；根据转向速度差值实时调整发动机转速和左右行走马达的转速,以稳定控制推土机的转向速度。本发明能够对推土机在负载情况下的转向速度进行自动调节,从而能够避免出现转向速度过快或过慢的情况,并能够提高推土机的工作效率和驾驶舒适性,此外,还能够有效降低推土机转向操作的难度,以及减小推土机转向时造成的操作冲击。(The invention provides a bulldozer steering control method and a bulldozer steering control system, wherein the method comprises the following steps: acquiring a steering mode of the bulldozer; acquiring a steering control command and an engine speed of the bulldozer; obtaining a target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed; acquiring the load pressure of the bulldozer and the actual steering speed under the action of the load pressure; obtaining a steering speed difference value of the bulldozer according to the target steering speed and the actual steering speed; and adjusting the rotating speed of the engine and the rotating speeds of the left and right traveling motors in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer. The invention can automatically adjust the steering speed of the bulldozer under the load condition, thereby avoiding the condition of excessively high or excessively low steering speed, improving the working efficiency and driving comfort of the bulldozer, effectively reducing the difficulty of steering operation of the bulldozer and reducing the operation impact caused by steering of the bulldozer.)

1. A steering control method for a bulldozer, which comprises an engine and left and right travel motors, is characterized by comprising the following steps:

acquiring a steering mode of the bulldozer;

acquiring a steering control command and an engine speed of the bulldozer;

obtaining a target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed;

acquiring the load pressure of the bulldozer and the actual steering speed under the action of the load pressure;

obtaining a steering speed difference value of the bulldozer according to the target steering speed and the actual steering speed;

and adjusting the rotating speed of the engine and the rotating speeds of the left and right traveling motors in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer.

2. The bulldozer steering control method according to claim 1, wherein said steering modes include a plurality of track steering modes and a plurality of handlebar steering modes, wherein each of said track steering modes and each of said handlebar steering modes constitute said steering mode in any combination.

3. The bulldozer steering control method according to claim 2, characterized in that said steering control command is a steering angle of said bulldozer steering handle.

4. The bulldozer steering control method according to claim 3, wherein obtaining the actual steering speed of the bulldozer under the load pressure includes:

acquiring the actual rotating speed of the left and right traveling motors;

and obtaining the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed difference between the left and right traveling motors.

5. The bulldozer steering control method according to claim 4, wherein adjusting the engine speed and the left and right travel motor speeds in real time in accordance with the steering speed difference comprises:

adjusting the engine speed according to the steering speed difference by adopting a TSC1 control mode;

and adjusting the rotating speed of the left and right walking motors by adopting a PID (proportion integration differentiation) adjusting algorithm according to the steering speed difference.

6. A steering control system for a bulldozer, which comprises an engine and left and right travel motors, comprising:

the man-machine interaction module is used for setting a steering mode of the bulldozer;

the first control module is used for directly controlling the bulldozer to steer and generating a steering control command;

a second control module to monitor and control the engine speed;

the first acquisition module is used for acquiring the load pressure of the bulldozer;

the second acquisition module is used for acquiring the actual rotating speed of the left and right walking motors;

the third control module is used for adjusting the rotating speed of the left and right walking motors;

a fourth control module, the fourth control module respectively with the human-computer interaction module, the first control module, the second control module, the first collection module, the second collection module, the third control module links to each other, the fourth control module is used for:

obtaining a target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed;

obtaining the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed of the left and right traveling motors;

obtaining a steering speed difference value of the bulldozer according to the target steering speed and the actual steering speed;

and correspondingly adjusting the rotating speed of the engine and the rotating speed of the left and right traveling motors respectively through the engine control module and the left and right traveling motor rotating speed adjusting module according to the steering speed difference so as to stably control the steering speed of the bulldozer.

7. The bulldozer steering control system of claim 6, wherein said steering modes include a plurality of track steering modes and a plurality of handlebar steering modes, wherein each of said track steering modes and each of said handlebar steering modes in any combination constitute said steering mode.

8. The bulldozer steering control system of claim 7, wherein said first control module is a steering handle of said bulldozer and said steering control command is a steering angle of said steering handle.

9. The bulldozer steering control system of claim 8, wherein said fourth control module is configured to derive an actual steering speed of said bulldozer under said load pressure from an actual difference in rotational speed between said left and right travel motors.

10. The bulldozer steering control system of claim 9, wherein said fourth control module is configured to:

adjusting the engine speed according to the steering speed difference by adopting a TSC1 control mode;

and adjusting the rotating speed of the left and right walking motors by adopting a PID (proportion integration differentiation) adjusting algorithm according to the steering speed difference.

Technical Field

The invention relates to the technical field of bulldozer control, in particular to a bulldozer steering control method and a bulldozer steering control system.

Background

The control that present market overwhelms majority bull-dozer turned to the mode is simple relatively, generally only sets up fast-slow gear, and speed variation and the simple direct ratio of angle of turning to from this, when selecting fast-gear operation bull-dozer to turn to, often lead to the bull-dozer to turn to the speed too fast, cause the bull-dozer to appear comparatively serious jolting, holistic travelling comfort is relatively poor, when selecting slow-gear operation bull-dozer to turn to, often lead to the bull-dozer to react lazily, cause the work efficiency of bull-dozer to be low.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the art described above. Therefore, an object of the present invention is to provide a method for controlling steering of a bulldozer, which can automatically adjust the steering speed of the bulldozer under a load condition, thereby avoiding the situation that the steering speed is too fast or too slow, improving the work efficiency and driving comfort of the bulldozer, and further effectively reducing the difficulty of the steering operation of the bulldozer and reducing the operation impact caused when the bulldozer steers.

The second purpose of the invention is to provide a bulldozer steering control system.

In order to achieve the above object, a first aspect of the present invention provides a method for controlling steering of a bulldozer, the bulldozer comprising an engine and left and right travel motors, the method comprising: acquiring a steering mode of the bulldozer; acquiring a steering control command and an engine speed of the bulldozer; obtaining a target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed; acquiring the load pressure of the bulldozer and the actual steering speed under the action of the load pressure; obtaining a steering speed difference value of the bulldozer according to the target steering speed and the actual steering speed; and adjusting the rotating speed of the engine and the rotating speeds of the left and right traveling motors in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer.

According to the bulldozer steering control method provided by the embodiment of the invention, the steering mode of the bulldozer is obtained, the steering control command and the engine rotating speed of the bulldozer are obtained, the target steering speed of the bulldozer is obtained according to the steering mode, the steering control command and the engine rotating speed, the load pressure of the bulldozer and the actual steering speed under the action of the load pressure are obtained, the steering speed difference of the bulldozer is obtained according to the target steering speed and the actual steering speed, and finally the engine rotating speed and the rotating speeds of the left and right traveling motors are adjusted in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer, so that the steering speed of the bulldozer under the load condition can be automatically adjusted, the situation that the steering speed is too high or too low can be avoided, the working efficiency and the driving comfort of the bulldozer can be improved, in addition, the difficulty of the steering operation of the bulldozer can be effectively reduced, and the operation impact caused when the bulldozer steers can be reduced.

In addition, the bulldozer steering control method provided by the above embodiment of the present invention may further have the following additional technical features:

according to one embodiment of the invention, the steering modes include a plurality of track steering modes and a plurality of handlebar steering modes, wherein each of the track steering modes and each of the handlebar steering modes in any combination constitute the steering mode.

According to one embodiment of the present invention, the steering control command is a steering angle of the bulldozer steering handle.

According to one embodiment of the present invention, the obtaining of the actual steering speed of the bulldozer under the load pressure comprises: acquiring the actual rotating speed of the left and right traveling motors; and obtaining the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed difference between the left and right traveling motors.

According to an embodiment of the present invention, adjusting the engine rotation speed and the left and right traveling motor rotation speed in real time according to the steering speed difference includes: adjusting the engine speed according to the steering speed difference by adopting a TSC1 control mode; and adjusting the rotating speed of the left and right walking motors by adopting a PID (proportion integration differentiation) adjusting algorithm according to the steering speed difference.

In order to achieve the above object, a second aspect of the present invention provides a steering control system for a bulldozer, which includes an engine and left and right travel motors, the system including: the man-machine interaction module is used for setting a steering mode of the bulldozer; the first control module is used for directly controlling the bulldozer to steer and generating a steering control command; a second control module to monitor and control the engine speed; the first acquisition module is used for acquiring the load pressure of the bulldozer; the second acquisition module is used for acquiring the actual rotating speed of the left and right walking motors; the third control module is used for adjusting the rotating speed of the left and right walking motors; a fourth control module, the fourth control module respectively with the human-computer interaction module, the first control module, the second control module, the first collection module, the second collection module, the third control module links to each other, the fourth control module is used for: obtaining a target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed; obtaining the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed of the left and right traveling motors; obtaining a steering speed difference value of the bulldozer according to the target steering speed and the actual steering speed; and correspondingly adjusting the rotating speed of the engine and the rotating speed of the left and right traveling motors respectively through the engine control module and the left and right traveling motor rotating speed adjusting module according to the steering speed difference so as to stably control the steering speed of the bulldozer.

According to the bulldozer steering control system provided by the embodiment of the invention, the man-machine interaction module, the first control module, the second control module, the first acquisition module, the second acquisition module and the third control module are respectively and correspondingly used for setting the steering mode of the bulldozer, the bulldozer is directly controlled to steer and generate a steering control command, the rotating speed of an engine is monitored and controlled, the load pressure of the bulldozer is obtained, the actual rotating speeds of a left walking motor and a right walking motor are acquired, the rotating speeds of the left walking motor and the right walking motor are adjusted, the fourth control module is respectively connected with the modules and is used for adjusting the rotating speed of the engine and the rotating speed of the left walking motor and the right walking motor according to the steering mode, the steering control command, the rotating speed of the engine, the actual rotating speed of the left walking motor and the right walking motor and the load pressure of the bulldozer, so as to stably control the steering speed, therefore, the situation that the steering speed is too high or too low can be avoided, the working efficiency and the driving comfort of the bulldozer can be improved, in addition, the steering operation difficulty of the bulldozer can be effectively reduced, and the operation impact caused when the bulldozer steers is reduced.

In addition, the bulldozer steering control system proposed according to the above-mentioned embodiment of the present invention may also have the following additional features:

according to one embodiment of the invention, the steering modes include a plurality of track steering modes and a plurality of handlebar steering modes, wherein each of the track steering modes and each of the handlebar steering modes in any combination constitute the steering mode.

According to one embodiment of the invention, the first control module is a steering handle of the bulldozer, and the steering control command is a steering angle of the steering handle.

According to one embodiment of the present invention, the fourth control module is configured to obtain an actual steering speed of the bulldozer under the load pressure from an actual difference in rotational speed between the left and right travel motors.

According to one embodiment of the invention, the fourth control module is configured to: adjusting the engine speed according to the steering speed difference by adopting a TSC1 control mode; and adjusting the rotating speed of the left and right walking motors by adopting a PID (proportion integration differentiation) adjusting algorithm according to the steering speed difference.

Drawings

FIG. 1 is a flowchart of a bulldozer steering control method according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the PID tuning algorithm for bulldozer steering control according to an embodiment of the present invention;

FIG. 3 is a block diagram of a bulldozer steering control system according to an embodiment of the present invention;

FIG. 4 is a schematic view showing the construction of a bulldozer steering control system according to an embodiment of the present invention;

FIG. 5 is a schematic structural view of a handlebar of one embodiment of the present invention;

FIG. 6 is a feature view of a handlebar of one embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the bulldozer steering control method and the bulldozer steering control system according to the embodiments of the present invention are primarily intended for a crawler type bulldozer having an engine and left and right travel motors provided corresponding to tracks, and the bulldozer steering control method according to the embodiments of the present invention will be first described with reference to fig. 1.

As shown in fig. 1, the bulldozer steering control method according to the embodiment of the present invention includes the steps of:

and S1, acquiring the steering mode of the bulldozer.

Specifically, when the driver performs a bulldozer steering operation, a steering mode of the bulldozer may be set by the human-computer interaction platform, and then the human-computer interaction platform may acquire the set steering mode, wherein the steering mode of the bulldozer may include a plurality of crawler steering modes and a plurality of handlebar steering modes, and each crawler steering mode and each handlebar steering mode may be arbitrarily combined to constitute the steering mode of the bulldozer.

More specifically, the steering modes may include two track steering modes, which may be respectively set to H, C, and three handlebar steering modes, which may be respectively set to F, S, N, whereby six steering modes, such as HS, HF, HN, CS, CF, CN, may be configured by two track steering modes, such as H, C, and three handlebar steering modes, such as F, S, N, in combination.

In summary, the steering modes of the bulldozer are set, namely, the track steering mode, such as H, C, and the handlebar steering mode, such as F, S, N, are respectively selected, wherein when the track steering mode H is selected, the speed of the track on one side of the bulldozer is controlled to be reduced while the speed of the track on the other side of the bulldozer is controlled to be unchanged during steering of the bulldozer, so that the steering speed of the bulldozer can be ensured to be lower, the safe operation of the bulldozer is ensured, and the bulldozer is suitable for leveling the ground and the ground with lower friction; when the crawler steering mode C is selected, the speed of the crawler on one side of the bulldozer is controlled to be reduced, and the speed of the crawler on the other side of the bulldozer is controlled to be increased in the same proportion when the bulldozer steers, so that the steering speed of the bulldozer can be ensured to be high, the operating efficiency of the bulldozer is improved, and the bulldozer is suitable for a bulldozer site with a large friction force.

Further, after selecting the track steering module, such as H, C, a handlebar steering mode, such as F, S, N, may be selected, wherein when handlebar steering mode F is selected, it indicates that the amplitude of the motion of the steering handlebar increases with the increase of the steering angle, and the acceleration thereof also changes faster, which may be macroscopically indicated as the steering angle of the steering handlebar is larger, the higher the acceleration thereof is; when the handle steering mode S is selected, the acceleration of the action amplitude of the control handle is reduced along with the increase of the steering angle, and the acceleration can be represented as that the increasing speed of the action amplitude of the control handle is smoothly increased in a macroscopic view; when the handlebar steering mode N is selected, the acceleration of the action amplitude of the steering handlebar is between F and S along with the increase of the steering angle, and macroscopically, the action amplitude of the steering handlebar is relatively smooth.

And S2, acquiring the steering control command and the engine speed of the bulldozer.

And S3, obtaining the target steering speed of the bulldozer according to the steering mode, the steering control command and the engine speed.

In one embodiment of the invention, the steering control command of the bulldozer can be obtained through the MCU, wherein the steering control command of the bulldozer can be the steering angle of the control handle of the bulldozer, and when the driver controls the control handle to perform the steering operation of the bulldozer, the mechanical action of the control handle can be fed back to the MCU through the steering angle of the control handle, so that the mechanical action can be converted into a machine command, i.e., the steering control command, and sent to the MCU.

Further, engine speed may be obtained by the engine controller, for example, engine speed may be continuously monitored by the ECM, and in addition, load rate, torque, and throttle performance parameters of the engine may be continuously monitored by the ECM.

Further, the steering mode acquired by the man-machine interaction platform and the engine speed acquired by the ECM can be transmitted to the MCU, and then the target steering speed of the bulldozer can be obtained through the MCU according to the steering mode, the steering control instruction and the engine speed.

And S4, acquiring the load pressure of the bulldozer and the actual steering speed under the action of the load pressure.

Specifically, the step of obtaining the actual steering speed of the bulldozer under the action of the load pressure comprises the following steps: acquiring the actual rotating speed of a left walking motor and a right walking motor; and obtaining the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed difference between the left walking motor and the right walking motor.

More specifically, the working pressure of the bulldozer can be collected through the pressure sensor, the load pressure can be sensed, the obtained load pressure can be sent to the MCU, meanwhile, the actual rotating speeds of the left and right walking motors can be correspondingly obtained through the left and right walking motor speed sensors respectively, the obtained actual rotating speeds of the left and right walking motors can be sent to the MCU, and the MCU can obtain the actual steering speed of the bulldozer under the action of the load pressure according to the actual rotating speed difference between the left and right walking motors.

And S5, obtaining the steering speed difference of the bulldozer according to the target steering speed and the actual steering speed.

In one embodiment of the present invention, the steering speed difference of the bulldozer may be obtained from the target steering speed and the actual steering speed by the MCU.

And S6, adjusting the rotating speed of the engine and the rotating speed of the left and right traveling motors in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer.

Specifically, the adjusting the engine rotation speed and the rotation speeds of the left and right travel motors in real time according to the steering speed difference in the above steps may include: adjusting the engine speed according to the steering speed difference by adopting a TSC1 control mode; and adjusting the rotating speed of the left and right walking motors by adopting a PID (proportion integration differentiation) adjusting algorithm according to the steering speed difference.

More specifically, an engine torque adjusting signal can be generated by the MCU according to the steering speed difference value in a TSC1 control mode, the engine torque can be further corrected and adjusted by the ECM according to the engine torque adjusting signal, and finally the engine speed is adjusted; in addition, a PID (proportion integration differentiation) regulation algorithm can be adopted by the MCU to generate a left and right traveling motor rotating speed regulation signal according to the steering speed difference, and the displacement of the left and right traveling motors can be further regulated by the left and right traveling motor proportional electromagnetic valve according to the left and right traveling motor rotating speed regulation signal, so that the rotating speeds of the left and right traveling motors are regulated to ensure that the rotating speed difference of the left and right traveling motors is within a set range, and the steering speed of the bulldozer is stably controlled.

In summary, it can be seen that the method for controlling the steering of the bulldozer according to the embodiment of the present invention can continuously monitor the influence of the load pressure change on the steering speed of the bulldozer during the entire steering control process, and can perform the cyclic correction operation on the load pressure change through the PID adjustment algorithm to control the steering speed of the bulldozer within the set range, so as to achieve the purpose of stably controlling the entire steering process.

As shown in FIG. 2, when the bulldozer is turning, the MCU may determine a target steering speed Vi of the bulldozer according to a selected steering mode of the bulldozer, a steering control command and an engine speed, and simultaneously, the MCU may obtain actual speeds of left and right traveling motors of the bulldozer under a load pressure, and may calculate an actual steering speed Vf of the bulldozer according to the actual speeds of the left and right traveling motors by differential calculation, further, the MCU may calculate a steering speed difference Δ V according to the difference between the target steering speed Vi and the actual steering speed Vf, further, the MCU may correct the engine torque according to the steering speed difference Δ V, and specifically may adjust the engine torque by a TSC1 control method, and simultaneously, the MCU may adjust the speeds of the left and right traveling motors according to the steering speed difference Δ V, and specifically may adjust the speeds of the left and right traveling motors by adjusting the displacement of the left and right traveling motors by a PID adjustment algorithm, further, the MCU can set the speeds of the left and right tracks of the bulldozer according to steering control instructions, such as the steering direction and the steering speed variation range, pre-set the difference range of the left and right tracks of the bulldozer, and finally feed the finally corrected actual steering speed Vf back to the input end of the MCU so as to continue to perform cyclic correction operation with the target steering speed Vi. By adjusting the steering differential speed of the left and right tracks of the bulldozer through the process, the bulldozer can be stably controlled within a preset difference range, so that the bulldozer can work according to the preset steering speed in the steering mode during steering.

It should be noted that, when the load pressure and the actual operating condition change during the steering of the bulldozer, the traveling speeds of the left and right crawler belts of the bulldozer change, and for example, when the load pressure of the bulldozer is high, the engine power is insufficient and the synchronization rate of the left and right traveling motors changes, and all the changes are directly reflected on the rotation speed changes of the left and right traveling motors, so that the actual steering speed Vf, which is the difference between the actual rotation speeds of the left and right traveling motors of the bulldozer, is finally selected as the feedback signal.

According to the bulldozer steering control method provided by the embodiment of the invention, the steering mode of the bulldozer is obtained, the steering control command and the engine rotating speed of the bulldozer are obtained, the target steering speed of the bulldozer is obtained according to the steering mode, the steering control command and the engine rotating speed, the actual steering speed of the bulldozer under the action of load pressure is obtained, the steering speed difference of the bulldozer is obtained according to the target steering speed and the actual steering speed, and finally the engine rotating speed and the rotating speeds of the left and right traveling motors are adjusted in real time according to the steering speed difference so as to stably control the steering speed of the bulldozer, so that the steering speed of the bulldozer under the load condition can be automatically adjusted, the situation that the steering speed is too high or too low can be avoided, the working efficiency and the driving comfort of the bulldozer can be improved, and the difficulty in steering operation of the bulldozer can be effectively reduced, and to reduce the operational shock caused when the bulldozer is turning.

In order to achieve the purpose, the embodiment of the invention also provides a bulldozer steering control system.

As shown in fig. 3, the bulldozer steering control system according to the embodiment of the present invention includes a human-computer interaction module 10, a first control module 20, a second control module 30, a first acquisition module 40, a second acquisition module 50, a third control module 60, and a fourth control module 70, where the fourth control module 70 is connected to the human-computer interaction module 10, the first control module 20, the second control module 30, the first acquisition module 40, the second acquisition module 50, and the third control module 60, respectively.

The human-computer interaction module 10 is used for setting a steering mode of the bulldozer; the first control module 20 is used for directly controlling the bulldozer to steer and generating a steering control command; the second control module 30 is used to monitor and control engine speed; the first acquisition module 40 is used for acquiring the load pressure of the bulldozer; the second acquisition module 50 is used for acquiring the actual rotating speed of the left and right walking motors; the third control module 60 is used to adjust the rotation speed of the left and right travel motors; the fourth control module 70 is configured to obtain a target steering speed of the bulldozer according to the steering mode, the steering control command, and the engine speed, obtain an actual steering speed of the bulldozer under the action of the load pressure according to the actual speeds of the left and right travel motors, obtain a steering speed difference of the bulldozer according to the target steering speed and the actual steering speed, and correspondingly adjust the engine speed and the speeds of the left and right travel motors respectively through the engine control module and the left and right travel motor speed adjustment module according to the steering speed difference, so as to stably control the steering speed of the bulldozer.

In one embodiment of the present invention, as shown in fig. 4, the human-computer interaction module 10 may be a human-computer interaction platform, and the steering mode of the bulldozer may be set by the human-computer interaction platform, wherein the steering mode of the bulldozer may include a plurality of track steering modes and a plurality of handlebar steering modes, and each track steering mode and each handlebar steering mode may be arbitrarily combined to form the steering mode of the bulldozer.

Specifically, as shown in fig. 4, the human-computer interaction platform may include a display screen 101 and a manipulation button 102, wherein the manipulation button 102 may correspond to a track steering mode, i.e., H, C steering mode setting, and a handlebar steering mode, i.e., F, S, N steering mode setting, whereby a combination of different steering modes may be performed by controlling different manipulation buttons 102, for example, six steering modes, e.g., HS, HF, HN, CS, CF, CN, may be configured by a combination of the track steering mode H, C and the handlebar steering mode F, S, N.

In summary, the steering modes of the bulldozer are set, namely, the track steering mode, such as H, C, and the handlebar steering mode, such as F, S, N, are respectively selected, wherein when the track steering mode H is selected, the speed of the track on one side of the bulldozer is controlled to be reduced while the speed of the track on the other side of the bulldozer is controlled to be unchanged during steering of the bulldozer, so that the steering speed of the bulldozer can be ensured to be lower, the safe operation of the bulldozer is ensured, and the bulldozer is suitable for leveling the ground and the ground with lower friction; when the crawler steering mode C is selected, the speed of the crawler on one side of the bulldozer is controlled to be reduced, and the speed of the crawler on the other side of the bulldozer is controlled to be increased in the same proportion when the bulldozer steers, so that the steering speed of the bulldozer can be ensured to be high, the operating efficiency of the bulldozer is improved, and the bulldozer is suitable for a bulldozer site with a large friction force.

Further, after selecting the track steering module, such as H, C, a handlebar steering mode, such as F, S, N, may be selected, wherein when handlebar steering mode F is selected, it indicates that the amplitude of the motion of the steering handlebar increases with the increase of the steering angle, and the acceleration thereof also changes faster, which may be macroscopically indicated as the steering angle of the steering handlebar is larger, the higher the acceleration thereof is; when the handle steering mode S is selected, the acceleration of the action amplitude of the control handle is reduced along with the increase of the steering angle, and the acceleration can be represented as that the increasing speed of the action amplitude of the control handle is smoothly increased in a macroscopic view; when the handlebar steering mode N is selected, the acceleration of the action amplitude of the steering handlebar is between F and S along with the increase of the steering angle, and macroscopically, the action amplitude of the steering handlebar is relatively smooth.

In one embodiment of the present invention, as shown in fig. 4, the first control module 20 may be a control handle of a bulldozer, and when a driver controls the control handle to perform a steering operation of the bulldozer, a mechanical action of the control handle may be fed back to the fourth control module 70, i.e., the MCU, through a steering angle of the control handle of the bulldozer, so that the mechanical action may be converted into a machine command, i.e., a steering control command, and transmitted to the fourth control module 70, i.e., the MCU, and in particular, the steering control command may be transmitted to the fourth control module 70, i.e., the MCU, through the CAN bus. In addition, as shown in FIG. 4, the first control module 20, i.e., the steering handle, also provides for travel control of the motor grader, thereby enabling both axial control of forward/reverse and left/right steering of the motor grader.

More specifically, the first control module 20 may be a joystick of a bulldozer shown in fig. 5, the relationship between the steering angle and the characteristic value of which is shown in fig. 6, the characteristic value of which increases stepwise as the steering angle increases, for example, the characteristic value is 0 when the steering angle is 0-4 °, the characteristic value is linearly increased to 902 when the steering angle is 4-17.5 °, the characteristic value is maintained 902 when the steering angle is 17.5-18.5 °, the characteristic value is linearly increased to 1000 when the steering angle is 18.5-23 °, the characteristic value is maintained at 1000 when the steering angle is 23-24 °, and the maximum steering angle of which is 24 °.

In one embodiment of the present invention, as shown in FIG. 4, the second control module 30 may be an engine ECM, and the engine speed may be continuously monitored by the ECM, and further, the engine load rate, torque, and throttle performance parameters may be continuously monitored by the ECM and sent to the fourth control module 70, i.e., MCU, and in particular, the steering control command may be sent to the fourth control module 70, i.e., MCU, via the CAN bus.

In an embodiment of the present invention, as shown in fig. 4, the first collecting module 40 may be a pressure sensor, and specifically, may be used to collect the working pressure of the bulldozer, further sense the load pressure and send the load pressure to the fourth control module 70, i.e., the MCU.

In an embodiment of the present invention, as shown in fig. 4, the second collecting module 50 may be a speed sensor, and specifically may include a left walking motor speed sensor 501 and a right walking motor speed sensor 502, which may be respectively used to obtain actual rotation speeds of the left and right walking motors and send the actual rotation speeds to the fourth control module 70, i.e., the MCU.

In one embodiment of the present invention, as shown in FIG. 4, the third control module 60 may be a proportional solenoid valve, and may specifically include a left travel motor proportional solenoid valve 601 and a right travel motor proportional solenoid valve 602.

In summary, the fourth control module 70, i.e. the MCU, CAN be connected to the first control module 20 through the CAN bus, namely a manipulating handle, a human-computer interaction module 10, namely a human-computer interaction platform and a second control module 30, i.e., the ECM, and, in particular, as shown in fig. 4, the fourth control module 70, i.e., the MCU, may be respectively connected to the first control module 20 through the CAN-H, CAN-L ports, namely a manipulating handle, a human-computer interaction module 10, namely a human-computer interaction platform and a second control module 30, i.e., the CAN-H, CAN-L port of the ECM, to receive the command via the human interaction module 10, i.e., the steering mode set by the human-computer interaction platform, and receives the steering control command sent by the first control module 20, i.e., the control handle, and the second control module 30, i.e., the engine speed monitored by the ECM, the target steering speed of the bulldozer may then be obtained based on the steering mode, the steering control command, and the engine speed. The connection of the fourth control module 70, i.e. the MCU, with the first control module 20, i.e. the joystick, the human-computer interaction module 10, i.e. the human-computer interaction platform, and the second control module 30, i.e. the ECM, is realized through the CAN bus, which CAN greatly reduce the cost and the failure rate of the hard-wired connection and CAN effectively save the cost.

Further, as shown in fig. 4, the fourth control module 70, i.e. the MCU, may be further connected to the first collection module 40, i.e. the pressure sensor, the second collection module 50, i.e. the left and right traveling motor speed sensors 501 and 502, and the third control module 60, i.e. the left and right traveling motor proportional solenoid valves 601 and 602, respectively, to obtain the actual rotation speed of the bulldozer under the load pressure and the actual rotation speed of the left and right traveling motors, and then obtain the actual steering speed of the bulldozer under the load pressure according to the actual rotation speed difference between the left and right traveling motors.

Further, the fourth control module 70, i.e., the MCU, may derive a steering speed differential of the bulldozer from the target steering speed and the actual steering speed, and may then adjust the engine speed based on the steering speed differential using the TSC1 control scheme, and may adjust the left and right travel motor speeds based on the steering speed differential using a PID tuning algorithm.

Specifically, the fourth control module 70, i.e., the MCU, may generate an engine torque adjustment signal according to the steering speed difference by using the TSC1 control method, and further may adjust the engine torque by the second control module 30, i.e., the ECM, according to the engine torque adjustment signal, to finally adjust the engine speed; in addition, the fourth control module 70, that is, the MCU, may further use a PID adjustment algorithm to generate a left/right traveling motor rotation speed adjustment signal according to the steering speed difference, and further may respectively adjust the displacement of the left/right traveling motor according to the left/right traveling motor rotation speed adjustment signal through the left/right traveling motor proportional solenoid valve 601 and the right/left traveling motor proportional solenoid valve 602, so as to adjust the rotation speed of the left/right traveling motor, so as to ensure the rotation speed difference of the left/right traveling motor within a set range, thereby stably controlling the steering speed of the bulldozer.

In summary, it can be seen that the steering control system of the bulldozer according to the embodiment of the present invention can continuously monitor the influence of the load pressure change on the steering speed of the bulldozer during the entire steering control process, and can perform the cyclic correction operation on the load pressure change through the PID adjustment algorithm to control the steering speed of the bulldozer within the set range, so as to achieve the purpose of stably controlling the entire steering process, and the working process of the steering control system of the bulldozer according to the embodiment of the present invention will be further described in detail with reference to the working schematic diagram of the PID adjustment algorithm for the steering control of the bulldozer shown in fig. 2.

As shown in FIG. 2, when the bulldozer is turning, the MCU may determine a target steering speed Vi of the bulldozer according to a selected steering mode of the bulldozer, a steering control command and an engine speed, and simultaneously, the MCU may obtain actual speeds of left and right traveling motors of the bulldozer under a load pressure, and may calculate an actual steering speed Vf of the bulldozer according to the actual speeds of the left and right traveling motors by differential calculation, further, the MCU may calculate a steering speed difference Δ V according to the difference between the target steering speed Vi and the actual steering speed Vf, further, the MCU may correct the engine torque according to the steering speed difference Δ V, and specifically may adjust the engine torque by a TSC1 control method, and simultaneously, the MCU may adjust the speeds of the left and right traveling motors according to the steering speed difference Δ V, and specifically may adjust the speeds of the left and right traveling motors by adjusting the displacement of the left and right traveling motors by a PID adjustment algorithm, further, the MCU can set the speeds of the left and right tracks of the bulldozer according to steering control instructions, such as the steering direction and the steering speed variation range, pre-set the difference range of the left and right tracks of the bulldozer, and finally feed the finally corrected actual steering speed Vf back to the input end of the MCU so as to continue to perform cyclic correction operation with the target steering speed Vi. By adjusting the steering differential speed of the left and right tracks of the bulldozer through the process, the bulldozer can be stably controlled within a preset difference range, so that the bulldozer can work according to the preset steering speed in the steering mode during steering.

It should be noted that, when the load pressure and the actual operating condition change during the steering of the bulldozer, the traveling speeds of the left and right crawler belts of the bulldozer change, and for example, when the load pressure of the bulldozer is high, the engine power is insufficient and the synchronization rate of the left and right traveling motors changes, and all the changes are directly reflected on the rotation speed changes of the left and right traveling motors, so that the actual steering speed Vf, which is the difference between the actual rotation speeds of the left and right traveling motors of the bulldozer, is finally selected as the feedback signal.

According to the bulldozer steering control system provided by the embodiment of the invention, the man-machine interaction module, the first control module, the second control module, the first acquisition module, the second acquisition module and the third control module are respectively and correspondingly used for setting the steering mode of the bulldozer, the bulldozer is directly controlled to steer and generate a steering control command, the rotating speed of an engine is monitored and controlled, the load pressure of the bulldozer is obtained, the actual rotating speeds of a left walking motor and a right walking motor are acquired, the rotating speeds of the left walking motor and the right walking motor are adjusted, the fourth control module is respectively connected with the modules and is used for adjusting the rotating speed of the engine and the rotating speed of the left walking motor and the right walking motor according to the steering mode, the steering control command, the rotating speed of the engine, the actual rotating speed of the left walking motor and the right walking motor and the load pressure of the bulldozer, so as to stably control the steering speed, therefore, the situation that the steering speed is too high or too low can be avoided, the working efficiency and the driving comfort of the bulldozer can be improved, in addition, the steering operation difficulty of the bulldozer can be effectively reduced, and the operation impact caused when the bulldozer steers is reduced.

In the present invention, unless otherwise expressly specified or limited, the term "coupled" is to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.