Driving starting control method for sitting-driving forward-moving forklift

Abstract

The invention relates to the technical field of forklift control, and discloses a driving starting control method for a sitting forward forklift, which comprises the following steps of: acquiring a starting intention signal of a driver; obtaining pallet fork lifting height information and pallet fork load information to determine a first parameter N used for evaluating the stability of the whole vehicle; obtaining forward and backward movement position information of the portal frame to determine a second parameter Q for evaluating the adhesive force of the driving wheel; according to the control modes of the traction motor corresponding to the different working conditions, the starting process of the vehicle is adaptively adjusted, starting control under the complex working conditions can be actively predicted and adapted, key parameters of stability and adhesive force are calculated and evaluated in real time at the starting moment, and the key parameters are compared with preset threshold values; the system can recognize risk working conditions such as high-position heavy load and forward movement of the portal frame in advance and automatically switch to a corresponding control mode, abnormal abrasion of tires is effectively reduced, and stability and control stability during starting of the vehicle are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of forklift control technology, and in particular to a method for controlling the starting and driving of a forklift with the driver moving forward. Background Technology

[0002] The starting control of existing reach trucks typically relies solely on the driver's operation (such as the depth of the accelerator pedal) for starting acceleration, without establishing a coupling relationship with the forward or backward movement of the mast and the real-time load status of the forks.

[0003] When the mast is moved to the foremost position and the forks are in a high, fully loaded state, the vehicle's center of gravity shifts significantly forward, reducing the positive pressure on the drive wheels and decreasing traction. If the vehicle is still accelerated from the drive wheel side in the conventional manner at this time, it is very easy to cause the drive wheels to slip, resulting in abnormal tire wear and affecting the smoothness and safety of starting.

[0004] Existing solutions either intervene with torque after slippage occurs by detecting wheel speed differences, or simply limit the maximum speed based on fork height. These solutions fail to fundamentally recognize that the actual load on the drive wheels and the overall vehicle starting stability are jointly determined by mast forward movement and fork load. Therefore, a preventative control method is urgently needed that predicts risks and adaptively adjusts the drive strategy before the starting command is issued. Summary of the Invention

[0005] The purpose of this invention is to provide a method for controlling the starting of a forklift with a driver-forward configuration, in order to solve the problems in the prior art. This method can actively identify and suppress the risk of slippage before the starting command, making the forklift start more stable and safe, while effectively extending tire life and reducing long-term operating costs.

[0006] This invention provides a method for controlling the starting and driving of a forklift with a driver's seat, comprising the following steps:

[0007] Obtain the driver's intention to start; Acquire fork lifting height information and fork load information to determine the first parameter N used to evaluate the stability of the entire vehicle; Acquire the gantry's forward and backward movement position information to determine the second parameter Q used to evaluate the drive wheel adhesion; Based on the starting intention signal, and combined with the comparison results of the first parameter N and the first preset threshold N1, and the comparison results of the second parameter Q and the second preset threshold Q1, the current working condition is determined to be any one of the following: normal working condition, gantry forward moving working condition, high-level heavy load working condition, or a combination of high-level heavy load and gantry forward moving working condition. The vehicle's starting process is adaptively adjusted according to the control mode of the traction motor corresponding to different working conditions.

[0008] In the above-described method for controlling the starting and movement of a forklift with a driver's seat, preferably, acquiring the driver's starting intention signal includes: The analog signal C3 monitors the vehicle's accelerator, and the switch signals B1 and B2 indicate the vehicle's direction of travel. The analog signal C3 varies from 0 to 5V. When C3 > 0V and gradually increases, it indicates that the driver has issued a request for vehicle acceleration. The switch signal B1 is either 0 or 1. When B1=1, it indicates that the driver has issued a request for the vehicle to move forward. The switch signal B2 can be either 0 or 1. When B2=1, it indicates that the driver has issued a request for the vehicle to reverse.

[0009] In the above-described method for controlling the starting and stopping of a reach truck, preferably, determining the first parameter N used to evaluate the overall vehicle stability includes: Monitor the fork height signal C1 and calculate the fork lifting height. h=C1 H max / 10 ; Monitor the load pressure signal C2 and calculate the pressure at the bottom of the front cylinder. P=C2 P max / 10 ; Calculate the load weight. F=(P-P1) A / 2 ; Calculate load quality. M1=F / g ; Calculate the product of the load mass and the distance from the load's center of gravity to the ground, i.e., the first parameter. N=M1 (D+h) ; Where h is the lifting height of the forks, H max P is the maximum lifting height of the forks. max P1 is the maximum cylinder bottom pressure, where P1 is the pressure generated at the bottom of the front cylinder by the gravity of the components moving with the forks, P1 is a set value, A is the effective working area of ​​the front cylinder, g is the gravitational acceleration, D is the load center distance, and for a given vehicle model, H... max P max A and D are both constant values.

[0010] In the above-described method for controlling the starting and driving of a reach truck, preferably, determining the second parameter Q used to evaluate the drive wheel adhesion includes: Monitor the forward and backward movement signal C4 of the mast and calculate the distance from the front end of the fork to the center of the drive wheel. L3 = L1 + C4 L max / 5 ; Calculate the torque of the movable gantry (including load) about the center of the drive wheels. Q=M1 g (L3+D)+M2 g (L3-L2) ; Where L1 is the distance from the fork tip face to the center of the drive wheel (when the mast is moved to its final position), L2 is the horizontal distance from the fork tip face to the center of gravity of the movable mast, and L3 is the distance from the fork tip face to the center of the drive wheel. max M2 represents the maximum forward movement distance, and M2 represents the mass of the mast that can move forward and backward. For a given vehicle model, L1 and L... max M2 and M2 are both constant values.

[0011] In the above-described method for controlling the starting and stopping of a forklift with a driver's seat, preferably, determining the current operating condition includes: When N < N1 and Q < Q1, the current operating condition is determined to be a normal operating condition. When N < N1 and Q ≥ Q1, the current working condition is determined to be the gantry forward movement working condition; When N≥N1 and Q<Q1, the current working condition is determined to be a high-level heavy-load working condition. When N≥N1 and Q≥Q1, the current working condition is determined to be a combined working condition.

[0012] The above-described method for controlling the starting and movement of a forklift with a driver-mounted reach truck, preferably, includes the following control modes: Under normal operating conditions, the target speed and acceleration time of the traction motor are both proportional to the strength of the starting intention signal; In the gantry forward movement condition, high-position heavy load condition, or combined condition, one or more different influence coefficients are applied to the target speed and acceleration time of the traction motor to adaptively adjust the traction motor speed and acceleration time.

[0013] The above-described method for controlling the starting and stopping of a forklift with a moving mast is preferably implemented when the mast is determined to be moving forward. The target speed of the traction motor is reduced by an influence coefficient K1, where 0 <K1<1; Adjust the acceleration time of the traction motor with the influence coefficient K2, where 1 < K2 < 2.

[0014] As described above, in a driving start control method for a rider-operated reach forklift, preferably, when it is determined that it belongs to the high-load and heavy-duty working condition; Reduce the target speed of the traction motor with the influence coefficient K3, where K3=N1 / N ; Adjust the acceleration time of the traction motor with the influence coefficient K4, where K4=N / N1 .

[0015] As described above, in a driving start control method for a rider-operated reach forklift, preferably, when it is determined that it belongs to the combined working condition, jointly adjust the target speed and acceleration time of the traction motor with the influence coefficients of the mast forward movement working condition and the high-load and heavy-duty working condition.

[0016] As described above, in a driving start control method for a rider-operated reach forklift, preferably, when the start intention signal indicates that the vehicle starts to reverse, the control mode further includes: On the basis of the influence coefficient determined according to the working condition, further reduce the target speed of the traction motor with the influence coefficient K5, where 0 < K5 < 1, and further adjust the acceleration time of the traction motor with the influence coefficient K6, where 1 < K6 < 2.

[0017] Compared with the prior art, the present invention can actively predict and adapt to the start control of complex working conditions. By calculating and evaluating the key parameters of stability and adhesion in real time at the moment of starting and comparing them with the preset thresholds, the system can identify risk working conditions such as high-load and heavy-duty, mast forward movement, etc. in advance and automatically switch to the corresponding control mode.

[0018] The present invention changes the traditional logic of post-correction or simple speed limit, effectively reduces the abnormal wear of tires, extends the service life of tires, and significantly improves the smoothness and handling stability of the vehicle when starting, especially in the combined working conditions of high-load and heavy-duty, mast extended forward or high-load and heavy-duty with mast extended forward. While ensuring operation safety, it also improves the driving experience and operation efficiency. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the position of the drive wheel and the vehicle body of the rider-operated reach forklift provided by the embodiment of the present invention; Figure 2 It is a flowchart of the driving start control method for the rider-operated reach forklift provided by the embodiment of the present invention.

[0020] Description of the Reference Numerals: 10. Vehicle body; 20. Carrier wheel; 30. Fork; 40. Mast; 50. Drive wheel. Detailed Implementation

[0021] The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0022] Figure 1 The diagram illustrates the drive wheel positions and body layout of an existing reach truck. The load-bearing wheels 20 are located at the front of the body 10, primarily bearing most of the vertical weight of the forks 30 and the load. The forks 30 are mounted on a movable mast 40 for picking up, handling, and stacking goods. The lifting height and load capacity of the forks 30 are key variables affecting the overall vehicle stability. The drive wheels 50 are located at the rear of the body 10, below or behind the driver, providing driving force. Their traction is crucial to preventing slippage. However, the starting acceleration of an existing reach truck is unrelated to the mast's forward position and the fork load. When the driver moves the mast 40 to its furthest point, the forks 30 are fully loaded. During acceleration from the drive wheel side, slippage may occur in the drive wheels 50, leading to tire wear and affecting vehicle start-up.

[0023] See Figure 2 As shown, this embodiment provides a method for controlling the starting of a reach truck, which aims to adaptively adjust the starting process by real-time evaluation of vehicle stability and drive wheel traction, thereby effectively preventing drive wheel slippage, improving starting safety and smoothness, and reducing tire wear. The control method includes the following steps: S100: Obtain the driver's intention to start signal; S200: Obtain fork lifting height information and fork load information to determine the first parameter N used to evaluate the stability of the entire vehicle; S300: Obtain the forward and backward movement position information of the gantry 40 to determine the second parameter Q used to evaluate the adhesion of the drive wheels; S400. Based on the starting intention signal, and combined with the comparison results of the first parameter N and the first preset threshold N1, and the comparison results of the second parameter Q and the second preset threshold Q1, determine that the current working condition is any one of the following: normal working condition, gantry forward moving working condition, high-level heavy load working condition, or a combination of high-level heavy load and gantry forward moving working condition. The S500 adaptively adjusts the vehicle's starting process according to the control mode of the traction motor corresponding to different working conditions.

[0024] In some embodiments, the control method is implemented by a corresponding control system, which includes an acquisition unit, a signal processing and control unit, and an execution unit. The signal acquisition unit comprises a fork height sensor, a pressure sensor, a mast forward / backward position sensor, a vehicle travel accelerator, and a vehicle travel direction switch. The fork height sensor detects the height of the forks off the ground; the pressure sensor detects the pressure at the bottom of the front lifting cylinder and calculates the load gravity as the forks move based on the pressure; the mast forward / backward position sensor detects the distance from the fork tip face to the center of the drive axle; and the vehicle travel thumb switch and vehicle travel direction switch detect the driver's vehicle travel intention.

[0025] The signal processing and control unit includes a controller, which is mainly used for signal processing, scientific computing, logical judgment, and control of the traction motor.

[0026] The main actuator is the traction motor, which controls the vehicle's speed and acceleration.

[0027] In some embodiments of this application, step S100, obtaining the driver's starting intention signal, includes: The analog signal C3 monitors the vehicle's accelerator, and the switch signals B1 and B2 indicate the vehicle's direction of travel. The analog signal C3 varies from 0 to 5V. When C3 > 0V and gradually increases, it indicates that the driver has issued a request for vehicle acceleration. The switch signal B1 is either 0 or 1. When B1=1, it indicates that the driver has issued a request for the vehicle to move forward. The switch signal B2 can be either 0 or 1. When B2=1, it indicates that the driver has issued a request for the vehicle to reverse.

[0028] See Figure 1 As shown, further, in step S200, the fork lifting height information and fork load information are fused to obtain a first parameter N used to evaluate the stability of the entire vehicle. The specific implementation method includes: Monitor the fork height signal C1 and calculate the fork lifting height. h=C1 H max / 10 ; Monitor the load pressure signal C2 and calculate the pressure at the bottom of the front cylinder. P=C2 P max / 10 ; Calculate the load weight. F=(P-P1) A / 2 ; Calculate load quality. M1=F / g ; Calculate the product of the load mass and the distance from the load's center of gravity to the ground, i.e., the first parameter. N=M1 (D+h) The larger the value of the first parameter N, the higher the risk of the forklift swaying or tipping over during acceleration.

[0029] Where: h: fork lifting height, in meters (m). C1: Variation range 0~10V, 10V corresponds to the maximum lifting height H of the forks. max , H max : Maximum lifting height of the forks, in meters (m). For a given vehicle model, H max It is a constant value; P: Front cylinder bottom pressure, unit is MPa. C2: Variation range 0~10V, 10V corresponds to the maximum cylinder bottom pressure P max , P max Maximum cylinder bottom pressure, in MPa. For a specific vehicle model, P max To determine the value, F: Load weight, in N (N). P1: The pressure generated at the bottom of the front cylinder by the weight of the components moving with the forks, measured in MPa. P1 is a constant. A: Effective working area of ​​the front cylinder, in mm². For a given vehicle model, A is a constant. M1: Load mass, in kg g: acceleration due to gravity, in m / s² 2 , N: The product of the load mass and the distance from the load's center of gravity to the ground, in kg / m. D: Load center distance, in meters. For a given vehicle model, D is a constant.

[0030] See Figure 1 As shown, further, in step S300, by shifting the gantry forward and backward, a second parameter Q for evaluating the adhesion of the drive wheels is obtained, the implementation method of which includes: Monitor the forward and backward movement signal C4 of the mast and calculate the distance from the front end of the fork to the center of the drive wheel. L3 = L1 + C4 L max / 5 ; Calculate the torque of the movable gantry (including load) about the center of the drive wheels. Q=M1 g (L3+D)+M2 g (L3-L2) The larger the value of the second parameter Q, the more the normal force on the drive wheel is reduced, the worse the adhesion, and the easier it is to slip.

[0031] Where L3 is the distance from the front face of the forks to the center of the drive wheel, in meters (m). L1: The distance from the front face of the forks to the center of the drive wheel (after the mast has been moved to its final position), in meters (m). For a given vehicle model, L1 is a constant. C4: Variation range 0~5V, 5V corresponds to the maximum forward movement distance L max , L max : Maximum forward movement distance, in meters (m). For a given vehicle model, L max For a constant value, Q: The torque exerted by the movable gantry (including load) about the center of the drive wheel, in Nm. M2: Mass of the movable mast, measured in kg. For a given vehicle model, M2 is a constant. L2: The horizontal distance from the front face of the forks to the center of gravity of the mast that can move back and forth, in meters. For a given vehicle model, L2 is a constant.

[0032] Further, in step S400, the controller compares the calculated real-time first parameter N and second parameter Q with pre-calibrated safety thresholds to determine the current operating condition. These first and second preset thresholds N1 and Q1 are set based on vehicle model parameters, tire adhesion characteristics, and safety factors. This embodiment will elaborate on this in conjunction with the starting intention signal, specifically: When B1=1, 0V<C3≤5V, and C3 gradually increases, N<N1, Q<Q1, execute S501, which is the normal working condition. The vehicle starts moving forward. At this time, the vehicle has good stability and sufficient adhesion of the drive wheels. When B1=1, 0V<C3≤5V, and C3 gradually increases, N<N1, Q≥Q1, execute S502, that is, the gantry forward movement condition, the vehicle moves forward and starts. At this time, the vehicle is stable, but the adhesion of the drive wheels decreases due to the forward movement of the load. When B1=1, 0V<C3≤5V, and C3 gradually increases, N≥N1, Q<Q1, S503 is executed, which is the high-load working condition. The vehicle starts moving forward. At this time, the adhesion of the drive wheels is still acceptable, but the overall vehicle stability risk is high. When B1=1, 0V<C3≤5V, and C3 gradually increases, N≥N1, Q≥Q1, S504 is executed, which is a combination of high-level heavy load and gantry forward movement. The vehicle starts moving forward. At this time, the vehicle faces both high stability risk and low adhesion risk, which is the worst working condition. When B2=1, 0V<C3≤5V, and C3 gradually increases, N<N1, Q<Q1, execute S505, which is the normal working condition, and the vehicle starts moving backward. When B2=1, 0V<C3≤5V, and C3 gradually increases, N<N1, Q≥Q1, execute S506, that is, the gantry forward movement condition, and the vehicle reverses and starts. When B2=1, 0V<C3≤5V, and C3 gradually increases, N≥N1, Q<Q1, execute S507, which is the high-level heavy-load condition, and the vehicle starts moving backward. When B2=1, 0V<C3≤5V, and C3 gradually increases, N≥N1, Q≥Q1, execute S508, which is the combined working condition of high-level heavy load and gantry forward movement, and the vehicle starts moving backward. Wherein: N1 is the first preset threshold, which is the threshold value of the product of the load mass and the distance from the load center of gravity to the ground, in kgm; Q1 is the second preset threshold, which is the threshold value of the torque exerted by the forward and backward moving mast (including the load) on the center of the drive wheel, in Nm. For example, for a 2t model: N1 = 10000 kgm, Q1 = 55000 Nm.

[0033] Furthermore, in step S500, the corresponding control mode is invoked according to different operating conditions to adjust the starting process. In this embodiment, it is preferable that each control mode defines different adjustment rules for the output characteristics of the traction motor: under normal operating conditions, the target speed and acceleration time of the traction motor are proportional to the strength of the starting intention signal; under gantry forward movement, high-position heavy load, or combined operating conditions, one or more different influence coefficients are applied to the target speed and acceleration time of the traction motor to adaptively adjust the traction motor speed and acceleration time.

[0034] Specifically, adhesion compensation is performed for the gantry forward movement condition: by reducing the maximum speed and extending the acceleration process, the driving force is released smoothly to adapt to the decreased adhesion.

[0035] For stability protection under high-load conditions: a dynamic influence coefficient is adopted. Based on the dynamic change of the first parameter N, the dynamic influence coefficient is inversely proportional to the first parameter N for the target speed of the traction motor, and directly proportional to the first parameter N for the acceleration time of the traction motor, so as to achieve adaptive adjustment with stricter restrictions as the risk increases.

[0036] For combined operating conditions, the two strategies mentioned above are applied in combination to implement the most conservative and stringent control.

[0037] Furthermore, for reverse start-up, a reverse correction coefficient is uniformly superimposed on all forward control strategies to further limit the speed and extend the acceleration time in order to cope with the impact of reverse acceleration on the adhesion of the drive wheels.

[0038] The control modes for different operating conditions are described in detail below: S501, Under normal operating conditions, vehicle starts moving forward: Control the speed of the traction motor. n1=V 1max (C3 / 5) 60 , Controlling the acceleration time of the traction motor T1=T 额定 C3 / 5 .

[0039] Where: n1: Target speed of the traction motor (under normal conditions, when the vehicle is moving forward and starting), in rpm. V 1max V: Maximum speed of the vehicle in the forward direction, in m / s. For a given vehicle type, V 1max For a constant value, 60: Unit conversion factor T1: The time it takes for the traction motor to accelerate from zero speed to the target speed (under normal conditions, when the vehicle is moving forward and starting), measured in seconds. T 额定 The time it takes for the traction motor to accelerate from zero speed to the set maximum speed, measured in seconds.

[0040] S502, Gantry forward movement condition, vehicle starts moving forward: Control the speed of the traction motor. n2=n1 K1 , Controlling the acceleration time of the traction motor T2=T1 K2 .

[0041] Where: n2: target speed of the traction motor (when the gantry moves forward and the vehicle starts moving forward), in rpm. K1: Motor speed influence coefficient (gantry forward movement), K1 < 1, in this embodiment, K1 = 0.6.

[0042] T2: The time it takes for the traction motor to accelerate from zero speed to the target speed (mast forward movement, vehicle start-up), in seconds. K2: Traction motor acceleration time influence coefficient (gantry forward movement), 1 < K2 < 2, in this embodiment, K2 = 1.67.

[0043] S503, High-load working condition, vehicle forward start: Control the speed of the traction motor. n3=n1 K3 , Controlling the acceleration time of the traction motor T3=T1 K4 .

[0044] Where: n3: Target speed of the traction motor (high-load, vehicle forward start), unit is rpm. K3: Motor speed influence coefficient (high-level heavy load), K3=N1 / N , T3: Time it takes for the traction motor to accelerate from zero speed to the target speed (high-load, vehicle starting), in seconds. K4: Traction motor acceleration time influence coefficient (high-level heavy load), K4=N / N1 .

[0045] S504, Combined Operating Conditions, Vehicle Forward Start: Control the speed of the traction motor. n4=n1 K1 K3 , Controlling the acceleration time of the traction motor T4=T1 K2 K4 .

[0046] Where: n4: Target speed of traction motor (high-load, gantry forward movement, vehicle forward start), unit is rpm. T4: The time it takes for the traction motor to accelerate from zero speed to the target speed (high-load, gantry forward movement, vehicle forward start), in seconds.

[0047] S505, under normal operating conditions, vehicle starting from reverse: Control the speed of the traction motor. n5=n1 K5 , Controlling the acceleration time of the traction motor T5=T1 K6 .

[0048] Where: n5: Target speed of the traction motor (under normal conditions, vehicle starting from reverse), in rpm. K5: Motor speed influence coefficient (driving direction), K5 < 1, in this embodiment, K5 = 0.8; T5: The time it takes for the traction motor to accelerate from zero speed to the target speed (under normal conditions, when the vehicle is reversing and starting), measured in seconds. K6: Traction motor acceleration time influence coefficient (driving direction), 1 < K6 < 2, in this embodiment, K6 = 1.25.

[0049] S506, Gantry forward movement condition, vehicle reverses and starts: Control the speed of the traction motor. n6=n2 K5 , Controlling the acceleration time of the traction motor T6=T2 K6 .

[0050] Where: n6: Target speed of the traction motor (mast forward movement, vehicle reversing and starting), in rpm. T6: The time it takes for the traction motor to accelerate from zero speed to the target speed (when the gantry moves forward and the vehicle starts moving backward), in seconds.

[0051] S507, under high-load conditions, vehicle reverse start: Control the speed of the traction motor. n7=n3 K5 , Controlling the acceleration time of the traction motor T7=T3 K6 .

[0052] Where: n7: Target speed of traction motor (high-load, vehicle reversing start), unit is rpm. T7: The time it takes for the traction motor to accelerate from zero speed to the target speed (high load, vehicle reversing and starting), in seconds.

[0053] S508, combined operating conditions, vehicle reversing and starting: Control the speed of the traction motor. n8=n4 K5 , Controlling the acceleration time of the traction motor T8=T4 K6 .

[0054] Where: n8: Target speed of traction motor (high-level heavy load, gantry forward movement, vehicle reverse start), unit is rpm. T8: The time it takes for the traction motor to accelerate from zero speed to the target speed (high-load, gantry forward movement, vehicle reversing and starting), in seconds.

[0055] Through the above steps, the method described in this invention can automatically identify the vehicle's state at the moment the starting command is issued and select the optimal control mode, thereby preventing slippage at its source and achieving a safe, smooth, and adaptive start. It should be noted that those skilled in the art will understand that the aforementioned sensor types, specific calculation formulas, and coefficient values ​​can all be adjusted and optimized according to different forklift models and control precision requirements, and these variations should all be included within the scope of protection of this invention.

[0056] The above description, based on the embodiments shown in the figures, details the structure, features, and effects of the present invention. The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent changes, that do not exceed the spirit covered by the specification and figures, should be within the protection scope of the present invention.

Claims

1. A method for controlling the starting and driving of a forklift with a driver's forward position, characterized in that, Includes the following steps: Obtain the driver's intention to start; Acquire fork lifting height information and fork load information to determine the first parameter N used to evaluate the stability of the entire vehicle; Acquire the gantry's forward and backward movement position information to determine the second parameter Q used to evaluate the drive wheel adhesion; Based on the starting intention signal, and combined with the comparison results of the first parameter N and the first preset threshold N1, and the comparison results of the second parameter Q and the second preset threshold Q1, the current working condition is determined to be any one of the following: normal working condition, gantry forward moving working condition, high-level heavy load working condition, or a combination of high-level heavy load and gantry forward moving working condition. The vehicle's starting process is adaptively adjusted according to the control mode of the traction motor corresponding to different working conditions.

2. The method for controlling the starting and driving of a forklift with a forward-moving driver according to claim 1, characterized in that, The acquisition of the driver's starting intention signal includes: The analog signal C3 monitors the vehicle's accelerator, and the switch signals B1 and B2 indicate the vehicle's direction of travel. The analog signal C3 varies from 0 to 5V. When C3 > 0V and gradually increases, it indicates that the driver has issued a request for vehicle acceleration. The switch signal B1 is either 0 or 1. When B1=1, it indicates that the driver has issued a request for the vehicle to move forward. The switch signal B2 can be either 0 or 1. When B2=1, it indicates that the driver has issued a request for the vehicle to reverse.

3. The method for controlling the starting and driving of a forklift with the driver on the other side as described in claim 1, characterized in that, The first parameter N used to evaluate vehicle stability includes: Monitor the fork height signal C1 and calculate the fork lifting height. h=C1 H max / 10 ; Monitor the load pressure signal C2 and calculate the pressure at the bottom of the front cylinder. P=C2 P max / 10 ; Calculate the load weight. F=(P-P1) A / 2 ; Calculate load quality. M1=F / g ; Calculate the product of the load mass and the distance from the load's center of gravity to the ground, i.e., the first parameter. N=M1 (D+h) ; Where h is the lifting height of the forks, H max P is the maximum lifting height of the forks. max P1 is the maximum cylinder bottom pressure, where P1 is the pressure generated at the bottom of the front cylinder by the gravity of the components moving with the forks, P1 is a set value, A is the effective working area of ​​the front cylinder, g is the gravitational acceleration, D is the load center distance, and for a given vehicle model, H... max P max A and D are both constant values.

4. The method for controlling the starting and driving of a forklift with a forward-moving mechanism according to claim 1, characterized in that, The determination of the second parameter Q used to evaluate the drive wheel adhesion includes: Monitor the forward and backward movement signal C4 of the mast and calculate the distance from the front end of the fork to the center of the drive wheel. L3 = L1 + C4 L max / 5 ; Calculate the torque of the movable gantry (including load) about the center of the drive wheels. Q=M1 g (L3+D)+M2 g (L3-L2) ； Where L1 is the distance from the fork tip face to the center of the drive wheel (when the mast is moved to its final position), L2 is the horizontal distance from the fork tip face to the center of gravity of the movable mast, and L3 is the distance from the fork tip face to the center of the drive wheel. max M2 represents the maximum forward movement distance, and M2 represents the mass of the mast that can move forward and backward. For a given vehicle model, L1 and L... max M2 and M2 are both constant values.

5. The method for controlling the starting and driving of a forklift with a forward-moving mechanism according to claim 1, characterized in that, Determining the current operating condition includes: When N < N1 and Q < Q1, the current operating condition is determined to be a normal operating condition. When N < N1 and Q ≥ Q1, the current working condition is determined to be the gantry forward movement working condition; When N≥N1 and Q<Q1, the current working condition is determined to be a high-level heavy-load working condition. When N≥N1 and Q≥Q1, the current working condition is determined to be a combined working condition.

6. The method for controlling the starting and driving of a forklift with a forward-moving mechanism according to claim 1, characterized in that, The control modes include: Under normal operating conditions, the target speed and acceleration time of the traction motor are both proportional to the strength of the starting intention signal; In the gantry forward movement condition, high-position heavy load condition, or combined condition, one or more different influence coefficients are applied to the target speed and acceleration time of the traction motor to adaptively adjust the traction motor speed and acceleration time.

7. The method for controlling the starting and driving of a forklift with a driver's seat forward according to claim 6, characterized in that, When it is determined that the gantry is moving forward; The target speed of the traction motor is reduced by an influence coefficient K1, where 0 <K1<1; The acceleration time of the traction motor is adjusted using an influence coefficient K2, where 1 <K2<2。 8. The method for controlling the starting and driving of a forklift with a driver's seat forward according to claim 6, characterized in that, When it is determined to be a high-level heavy-load working condition; The target speed of the traction motor is reduced by an influence coefficient K3, wherein... K3=N1 / N ; The acceleration time of the traction motor is adjusted using an influence coefficient K4, wherein, K4=N / N1 .

9. The method for controlling the starting and driving of a forklift with a driver's seat forward according to claim 6, characterized in that, When it is determined that the combined working condition is involved, the target speed and acceleration time of the traction motor are adjusted together using the influence coefficients of the gantry forward movement condition and the high-position heavy load condition.

10. The method for controlling the starting and driving of a forklift with a driver's seat forward according to claim 6, characterized in that, When the start intention signal indicates that the vehicle starts to reverse, the control mode further includes: Based on the influence coefficient determined according to the working condition, further reducing the target speed of the traction motor by the influence coefficient K5, where 0 < K5 < 1, and further adjusting the acceleration time of the traction motor by the influence coefficient K6, where 1 < K6 < 2.

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