Automatic shovel loading loader vehicle control method

Abstract

The present application proposes a vehicle control method for a loader with automatic shoveling, which relates to the technical field of loaders. The method includes: a shoveling switch and an automatic shoveling switch are provided in the cab of the loader. When the shoveling switch and the automatic shoveling switch are in the on mode, the loader is controlled by the vehicle controller to complete the shoveling process. Specifically, in the automatic shoveling stage, the controller sends a command to the engine to move the loader forward, and controls the bucket cylinder and the boom cylinder to complete the intelligent drag reduction shoveling; in the automatic unloading stage, the controller sends a command to the engine to lift the boom cylinder to a fixed height, and the bucket cylinder is turned to pour out the material; in the automatic reset stage, the controller sends a command to the engine to control the loader to move backward, flip the bucket to a horizontal level, make the bucket face the material, and lower the boom to the height of the material. The present application using the above scheme realizes the intelligent drag reduction shoveling of the loader.

Description

Technical Field

[0001] The present application relates to the technical field of loaders, and in particular to a method for controlling a whole vehicle of an automatic shoveling loader. Background Art

[0002] When the loader is shoveling, the bucket will apply a forward load to the material pile in front of it near the tooth tip while adding material in the bucket, thereby increasing the density of the material in front of the bucket (i.e., the formation of a dense core). When the loader bucket is inserted deeper into the pile, the density of the material in front of the bucket increases (the length of the dense core increases), and the area above the dense core increases as a function with an exponential greater than 1. When the length of the dense core increases to a certain value, the torque provided by the engine cannot meet the requirements for forward movement, which will cause the loader tires to slip and cause power waste.

[0003] Currently, loaders have problems such as high power consumption and low intelligence level. Summary of the invention

[0004] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, the purpose of this application is to propose a vehicle control method for a loader with automatic shoveling, which solves the technical problem of low intelligence level of existing methods and realizes intelligent control and intelligent drag reduction shoveling of the loader.

[0006] To achieve the above-mentioned purpose, an embodiment of the present application proposes a vehicle control method for an automatic shoveling loader, including a loader cab provided with a shoveling switch and an automatic shoveling switch, when the shoveling switch and the automatic shoveling switch are in the on mode, the loader is controlled by the vehicle controller to complete the shoveling process, wherein the shoveling process includes an automatic shoveling stage, an automatic unloading stage and an automatic resetting stage, and the loader is controlled to complete the shoveling process, including: in the automatic shoveling stage, a command is issued to the engine by the controller to make the loader move forward, and the bucket cylinder and the boom cylinder are controlled to complete the intelligent drag reduction shoveling; in the automatic unloading stage, a command is issued to the engine by the controller to lift the boom cylinder to a fixed height, and the bucket cylinder is turned to pour out the material; in the automatic resetting stage, a command is issued to the engine by the controller to control the loader to move backward, flip the bucket to a horizontal state, make the bucket face the material, and lower the boom to the material height.

[0007] The automatic shoveling loader vehicle control method of the embodiment of the present application realizes intelligent control of the loader's working process through automatic shoveling, automatic unloading and automatic resetting. By using an intelligent drag reduction strategy during automatic shoveling, intelligent drag reduction during automatic loading of the loader is realized, effectively avoiding the problem of tire slippage.

[0008] Optionally, in one embodiment of the present application, the intelligent drag reduction shoveling installation includes an insertion phase and a lifting phase, and controlling the loader to complete the intelligent drag reduction shoveling installation includes:

[0009] In the insertion stage, when the tire slippage of the loader is detected, a control signal is input into the hydraulic system through the controller to realize the boom lifting a fixed distance and inserting the material to a fixed depth. When the tire slippage of the loader is not detected, the boom is controlled to work normally and insert the material to a fixed depth. The determination condition of the tire slippage is that the difference between the tire speed and the actual vehicle speed is greater than a preset threshold value;

[0010] During the lifting stage, the bucket cylinder and the boom cylinder are controlled to work simultaneously, so that the bucket moves forward and flips at the same time. After the bucket blade is separated from the material, the boom is controlled to stop moving, and the bucket is controlled to continue flipping until it is in the transport state.

[0011] Optionally, in one embodiment of the present application, before controlling the loader to move forward or backward, it also includes:

[0012] Receive the loader start command, determine whether the loader meets the starting conditions, obtain the throttle signal when the starting conditions are met, collect the throttle depth, calculate the target torque according to the throttle depth, and send a control command to the engine control system according to the target torque to control the loader to start.

[0013] Optionally, in one embodiment of the present application, before controlling the loader to move forward or backward, it also includes:

[0014] Determine whether a start-up prevention signal is received, if the signal is received, stop sending control instructions to the engine control system, if the signal is not received, determine whether the loader is in a stationary state, and send a brake interlock lock instruction when the loader is in a stationary state;

[0015] Determine whether the accelerator pedal output reaches the minimum torque. If so, send a brake interlock unlock command.

[0016] Optionally, in one embodiment of the present application, before controlling the loader to move forward or backward, it also includes:

[0017] Obtain loader throttle signal and brake signal;

[0018] Determine whether the braking depth of the loader meets the first condition. If so, set the loader throttle signal to 0. If not, determine whether the braking depth of the loader meets the second condition. If so, linearly attenuate the loader throttle signal according to the braking depth. If not, maintain the loader throttle signal.

[0019] Optionally, in one embodiment of the present application, the method further includes: collecting input signals and information of the loader, and sending them to a corresponding module of the loader for processing, wherein the process of processing the input signals of the loader includes:

[0020] Collect brake pedal signals, handbrake switch signals or air pressure sensor signals, convert them into corresponding electrical signals according to the air pressure values, and transmit them to the corresponding power controller through the CAN network;

[0021] Collect throttle and brake control signals, calculate throttle opening and brake travel according to pedal position, and transmit them to the corresponding power controller through the CAN network;

[0022] Send the CAN message of the above signal to the CAN network of the whole vehicle.

[0023] Optionally, in one embodiment of the present application, the method further includes: monitoring the current state of the loader and sending an alarm signal when the loader fails, wherein the process of monitoring the loader includes:

[0024] According to the current loader status, monitor whether the vehicle is overheated, and send an alarm message to the corresponding loader instrument when the loader is overheated;

[0025] Monitor the power system status and issue an alarm when a power system failure occurs;

[0026] Monitor engine speed and send an alarm to the vehicle when the engine speed exceeds the threshold;

[0027] Monitor the power system torque limit status and send an alarm to the vehicle when abnormal;

[0028] Monitor whether the received CAN signal, analog signal and switch signal are invalid, and perform corresponding failure processing when they fail.

[0029] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0031] Figure 1 This is a force diagram of the shoveling process of an embodiment of the present application;

[0032] Figure 2 A schematic flow chart of a method for controlling a whole vehicle of a loader with automatic shoveling provided in the first embodiment of the present application;

[0033] Figure 3 This is a schematic diagram of the intelligent drag reduction shoveling process of an embodiment of the present application. DETAILED DESCRIPTION

[0034] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0035] When the loader is shoveling, the bucket will apply a forward load to the material pile in front of it near the tooth tip while adding material in the bucket, thereby increasing the density of the material in front of the bucket (i.e., the formation of a dense core). When the loader bucket is inserted deeper into the pile, the density of the material in front of the bucket increases (the length of the dense core increases), and the area above the dense core increases as a function with an exponential greater than 1. When the length of the dense core increases to a certain value, the torque provided by the engine cannot meet the requirements for forward movement, which will cause the loader tires to slip and cause power waste.

[0036] The relationship between the length of the compacted core Lt and the horizontal insertion depth Lc of the loader bucket in the pile is:

[0037] ;

[0038] Where da is the diameter of the pile particles, K f is the bucket shape coefficient, Kg is the influence coefficient of the angle between the bucket bottom and the ground;

[0039] The insertion resistance is:

[0040] ;

[0041] Among them, K 1 K is the influence coefficient of material block size and looseness, 2 is the influence coefficient of material type, Lc is the depth of the bucket inserted into the pile, Bg is the width of the bucket, K 3 is the influence coefficient of stockpile height;

[0042] like Figure 1 As shown, the shoveling process includes shoveling resistance, bucket resistance and insertion resistance, among which,

[0043] The shoveling resistance is:

[0044] ;

[0045] in, The shear stress of the material when the bucket is lifted;

[0046] Bucket resistance:

[0047] ;

[0048] Among them, M e Q is the static resistance moment when the bucket starts to rotate, H is the rated load of the loader, G e is the bucket weight, l B It is the horizontal distance from the bucket's center of gravity to the bucket's rotation center;

[0049] The static resistance when the bucket is rotating is:

[0050] ;

[0051] Where x is the horizontal distance between the bucket rotation center and the bucket edge, lc is the vertical distance from the bucket rotation center to the force acting on the bucket connecting rod, and y is the vertical distance between the bucket rotation center and the ground.

[0052] The following describes the automatic shoveling loader vehicle control method of an embodiment of the present application with reference to the accompanying drawings.

[0053] Figure 2 A schematic flow chart of a method for controlling a whole-vehicle loader with automatic shoveling provided in the first embodiment of the present application.

[0054] like Figure 2 As shown, the automatic shovel loading loader vehicle control method includes the following steps:

[0055] Step 201, in the automatic shoveling stage, the controller sends a command to the engine to make the loader move forward, and controls the bucket cylinder and the boom cylinder to complete the intelligent drag-reducing shoveling;

[0056] According to some embodiments, the automatic shoveling and loading stage specifically includes: after the loader is reset, it stops next to the material (the bucket is facing the material), the automatic shoveling and loading button is pressed to start the automatic shoveling and loading module, the controller sends a command to the engine, starts the loader to move forward, controls the bucket cylinder and the boom cylinder to complete the intelligent drag reduction shoveling and loading, and after the shoveling and loading action is completed, the loader stops.

[0057] In some embodiments, in order to solve the problem of loader slippage, an intelligent drag reduction shoveling control strategy is developed. The tire speed during shoveling is compared with the actual vehicle speed, and the difference between the two is used as the judgment condition for whether the tire slips under the shoveling condition. When the judgment condition is met (i.e., tire slippage), the intelligent drag reduction strategy is activated.

[0058] In some embodiments, Figure 3 As shown, the intelligent drag reduction strategy is divided into two parts: the insertion stage and the lifting stage.

[0059] During the insertion stage, when the loader's skidding self-detection detects tire slippage, the controller will input a control signal into the hydraulic system to lift the boom to a fixed distance (this distance can be changed on the display screen according to the material), thereby destroying the density of the material near the bucket. If tire slippage is not detected, there is no need to lift the boom. After inserting the material to a fixed depth (this depth can be changed on the display screen according to the material), the insertion stage is completed.

[0060] During the lifting stage, the bucket cylinder and the boom cylinder work simultaneously, the bucket moves forward and flips at the same time, the boom stops moving after the bucket blade separates from the material, and the bucket continues to flip until it is in the transport state.

[0061] Step 202, in the automatic unloading stage, the controller sends a command to the engine to lift the boom cylinder to a fixed height, and the bucket cylinder dumps the material;

[0062] According to some embodiments, the automatic unloading stage specifically includes: after the loader completes the shoveling action, it drives to the unloading point. Pressing the automatic shoveling button starts the automatic unloading module, and the controller sends a command to the engine to first lift the boom cylinder, and after it is lifted to a fixed height, the bucket cylinder dumps the material.

[0063] Step 203, in the automatic reset stage, the controller sends a command to the engine to control the loader to move backward, flip the bucket to a horizontal level so that the bucket faces the material, and lower the boom to the height of the material.

[0064] According to some embodiments, the automatic reset stage specifically includes: after the loader completes the unloading action, it moves backward for a distance to make room for the bucket to reset. Pressing the automatic shovel button starts the automatic reset module, and the controller sends a command to the engine to first flip the bucket to horizontal, and then lower the boom to the initial stage.

[0065] The automatic shoveling loader vehicle control method of the embodiment of the present application realizes intelligent control of the loader's working process through automatic shoveling, automatic unloading and automatic resetting. By using an intelligent drag reduction strategy during automatic shoveling, intelligent drag reduction during automatic loading of the loader is realized, effectively avoiding the problem of tire slippage.

[0066] Optionally, in one embodiment of the present application, the driving control function strategy of the loader includes a brake interlock strategy and a brake priority strategy. Specifically,

[0067] (1) Enter manual driving / assisted driving mode according to driving instructions.

[0068] (2) Brake interlock strategies include:

[0069] If a start-up prevention signal is received, the torque output is stopped;

[0070] If the start-up prevention signal is not received, the brake interlock lock command is sent in the stationary state;

[0071] When the accelerator pedal is depressed and the output reaches the minimum torque, a brake interlock unlocking command is sent;

[0072] The minimum unlocking torque is set to the minimum starting torque of each ramp. If the output torque is greater than the minimum starting torque of each ramp, the device will be unlocked. The unlocking torque must be greater than 0.

[0073] If the start-up prevention switch signal is collected when the brake interlock is effective, the brake interlock is kept locked until the unlocking condition is met and the unlocking command is sent continuously.

[0074] (3) Calculate the required torque and send control instructions to the engine control system.

[0075] (4) Braking priority strategies include:

[0076] Braking depth>30%, throttle set to 0;

[0077] The throttle decays linearly to 0 between 10% and 30%;

[0078] If the execution throttle depth is less than 10%, the throttle signal will be processed effectively.

[0079] Optionally, in one embodiment of the present application, the signal collection and processing of the loader includes collecting signals such as gear, throttle, brake, air pressure, etc., and performing corresponding processing, specifically, including the following functions:

[0080] Brake air pressure signal processing function: collect brake air pressure signals, process them accordingly and send them to the power grid.

[0081] Throttle and brake pedal signal processing function: collect throttle and brake pedal signals, process them accordingly and send them to the power network.

[0082] Handbrake signal processing function: collect handbrake switch or handbrake air pressure sensor, process it accordingly and send it to the power network.

[0083] CAN message forwarding function: send messages to the corresponding network.

[0084] Optionally, in one embodiment of the present application, monitoring and alarming the loader specifically include the following functions:

[0085] Overheating alarm function: According to the current vehicle status, determine whether the vehicle is overheated, and send the relevant alarm status to the instrument for display.

[0086] Power system fault alarm function: alarm when power system fails.

[0087] Overspeed alarm function: When the engine speed is too high, an alarm will be sounded to the entire vehicle.

[0088] Power system torque limit alarm function: monitors the power system torque limit and alarms the entire vehicle if an abnormality is found.

[0089] Signal failure processing function: failure processing of received CAN signals, analog signals and switch signals.

[0090] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0091] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0092] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0093] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0094] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0095] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0096] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0097] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for controlling a loader vehicle with automatic shovel loading, characterized in that: The cab of the loader is provided with a shoveling switch and an automatic shoveling switch. When the shoveling switch and the automatic shoveling switch are in the on mode, the loader is controlled by the vehicle controller to complete the shoveling process, wherein the shoveling process includes an automatic shoveling stage, an automatic unloading stage and an automatic resetting stage. Controlling the loader to complete the shoveling process includes: During the automatic shoveling stage, the controller sends a command to the engine to make the loader move forward and control the bucket cylinder and boom cylinder to complete intelligent drag-reducing shoveling. In the automatic unloading stage, the controller sends a command to the engine to lift the boom cylinder to a fixed height, and the bucket cylinder dumps the material; In the automatic reset stage, the controller sends a command to the engine to control the loader to move backward, flip the bucket to a horizontal level so that the bucket faces the material, and lower the boom to the height of the material; The intelligent drag reduction shoveling installation includes an insertion phase and a lifting phase, and controlling the loader to complete the intelligent drag reduction shoveling installation includes: In the insertion stage, when the tire slippage of the loader is detected, a control signal is input into the hydraulic system through the controller to realize the boom lifting a fixed distance and inserting the material to a fixed depth. When the tire slippage of the loader is not detected, the boom is controlled to work normally and insert the material to a fixed depth, wherein the determination condition of the tire slippage is that the difference between the tire speed and the actual vehicle speed is greater than a preset threshold value; During the lifting stage, the bucket cylinder and the boom cylinder are controlled to work simultaneously, so that the bucket moves forward and flips at the same time. After the bucket blade is separated from the material, the boom is controlled to stop moving, and the bucket is controlled to continue flipping until it is in the transport state.

2. The automatic shovel loading loader vehicle control method according to claim 1, characterized in that: Before controlling the loader to move forward or backward, the method further comprises: A loader start command is received to determine whether the loader meets the start condition, a throttle signal is acquired when the start condition is met, a throttle depth is collected, a target torque is calculated according to the throttle depth, and a control command is sent to the engine control system according to the target torque to control the start of the loader.

3. The automatic shovel loading loader vehicle control method according to claim 1, characterized in that: Before controlling the loader to move forward or backward, the method further comprises: Determine whether a start-up prevention signal is received, if the signal is received, stop sending control instructions to the engine control system, if the signal is not received, determine whether the loader is in a stationary state, and send a brake interlock lock instruction when the loader is in a stationary state; Determine whether the accelerator pedal output reaches the minimum torque. If so, send a brake interlock unlock command.

4. The automatic shovel loading loader vehicle control method according to claim 1, characterized in that: Before controlling the loader to move forward or backward, the method further comprises: Obtain loader throttle signal and brake signal; Determine whether the braking depth of the loader meets the first condition. If so, set the loader throttle signal to 0. If not, determine whether the braking depth of the loader meets the second condition. If so, linearly attenuate the loader throttle signal according to the braking depth. If not, maintain the loader throttle signal.

5. The automatic shovel loading loader vehicle control method according to claim 1, characterized in that: The method further includes: collecting input signals and information of the loader and sending them to a corresponding module of the loader for processing, wherein the process of processing the input signals of the loader includes: Collect brake pedal signals, handbrake switch signals or air pressure sensor signals, convert them into corresponding electrical signals according to the air pressure values, and transmit them to the corresponding power controller through the CAN network; Collect throttle and brake control signals, calculate throttle opening and brake travel according to pedal position, and transmit them to the corresponding power controller through the CAN network; Send the CAN message of the above signal to the CAN network of the whole vehicle.

6. The automatic shovel loading loader vehicle control method according to claim 1, characterized in that: The method further includes: monitoring the current state of the loader and sending an alarm signal when the loader fails, wherein the process of monitoring the loader includes: According to the current loader status, monitor whether the vehicle is overheated, and send an alarm message to the corresponding loader instrument when the loader is overheated; Monitor the power system status and issue an alarm when a power system failure occurs; Monitor engine speed and send an alarm to the vehicle when the engine speed exceeds the threshold; Monitor the power system torque limit status and send an alarm to the vehicle when abnormal; Monitor whether the received CAN signal, analog signal and switch signal are invalid, and perform corresponding failure processing when they fail.

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