An unmanned forklift truck handling method and system based on a synchronous motor

Abstract

The application discloses an unmanned forklift carrying method based on a synchronous motor, and comprises the following steps: acquiring a current conveying line, segmenting a path according to a turning point, an initial point and a destination point in the conveying line to obtain a plurality of path segments; acquiring the weight of goods loaded on the unmanned forklift, determining a final braking distance according to the weight of the goods; acquiring the operation parameters of a synchronous motor of the unmanned forklift, determining an acceleration distance according to the operation parameters; and dividing the path segments according to the final braking distance and / or the acceleration distance to determine a control segment in each path segment, wherein the control segment comprises a deceleration segment, an acceleration segment and a uniform speed segment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned forklift control, and particularly relates to an unmanned forklift carrying method and system based on a synchronous motor. BACKGROUND

[0002] In an automated production workshop, in order to solve the problem of carrying goods, an unmanned forklift is designed to carry the goods automatically. Before carrying the goods, the delivery route of the unmanned forklift needs to be set in advance. After the worker loads the goods, the unmanned forklift can be started, and the unmanned forklift will carry the goods to the corresponding terminal according to the pre-delivery route.

[0003] However, during the transportation process, the goods are usually not limited and tightened, which causes the goods to be easily affected by inertia during movement, especially at the turning position of the delivery route, and the goods are prone to falling at this position. Therefore, how to control the unmanned forklift to effectively control the unmanned forklift from falling the goods during turning has become a problem to be solved. SUMMARY

[0004] In view of the above defects, the present application aims to provide an unmanned forklift carrying method and system based on a synchronous motor to solve the problem of goods falling due to poor stability of the unmanned forklift during turning.

[0005] To achieve this purpose, the present application adopts the following technical solution: an unmanned forklift carrying method based on a synchronous motor, comprising the following steps:

[0006] Step S1: obtaining a current delivery route, segmenting the route according to the turning point, initial point and destination point in the delivery route to obtain a plurality of route segments;

[0007] Step S2: obtaining the weight of the goods loaded by the unmanned forklift, and determining the final braking distance according to the weight of the goods;

[0008] Step S3: obtaining the operating parameters of the synchronous motor of the unmanned forklift, and determining the acceleration distance according to the operating parameters;

[0009] Step S4: dividing the route segments according to the final braking distance and / or acceleration distance to determine the control segments in each route segment, wherein the control segments include deceleration segments, acceleration segments and constant speed segments;

[0010] Step S5: when the unmanned forklift passes through different control segments, the speed of the unmanned forklift is controlled correspondingly.

[0011] Preferably, the step of obtaining the final braking distance in step S2 is as follows:

[0012] Step S21: selecting the speed range of the unmanned forklift according to the weight of the goods;

[0013] Step S22: obtaining the highest speed in the speed interval as a first operation speed, obtaining the friction coefficient of the unmanned forklift tire, and obtaining a preliminary braking distance by the friction coefficient and the first operation speed;

[0014] Step S23: obtaining the weight of the unmanned forklift and the goods as a total weight, and obtaining an inertia adjustment coefficient according to the total weight, the friction coefficient and the first operation speed;

[0015] Step S24: obtaining the final braking distance by multiplying the inertia adjustment coefficient by the preliminary braking distance.

[0016] Preferably, the specific formula for obtaining the preliminary braking distance in step S22 is as follows:

[0017] ;

[0018] Wherein S1 is the preliminary braking distance, is the first operation speed, g is the acceleration of gravity, is the friction coefficient;

[0019] The specific formula for obtaining the inertia adjustment coefficient in step S23 is as follows:

[0020] ;

[0021] Wherein C is an error correction coefficient greater than 1, a1, a2, a3 are respectively a total weight adjustment factor, a speed adjustment factor and a friction coefficient adjustment factor, and m is the total weight.

[0022] Preferably, the step of determining the acceleration distance in step S3 is as follows:

[0023] Step S31: obtaining the lowest speed in the speed interval as a second operation speed;

[0024] Obtaining the maximum torque of the motor;

[0025] Step S32: obtaining the acceleration of the unmanned forklift by the total mass and the maximum torque;

[0026] Step S33: obtaining the acceleration distance by the acceleration and the second operation speed;

[0027] Wherein the formula for obtaining the acceleration is as follows:

[0028] ;

[0029] The formula for obtaining the acceleration distance is as follows:

[0030] ;

[0031] wherein F is the maximum torque, V2 is the second operating speed.

[0032] Preferably, the rules for determining the deceleration section, the acceleration section and the constant speed section in step S4 are as follows:

[0033] The sum of the final braking distance and the acceleration distance is obtained as the first distance.

[0034] If the length of the section is greater than the first distance, the starting point of the section is taken as the first base point, the acceleration distance is added to the first base point in the direction of the ending point to obtain the acceleration section of the section, the ending point of the section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to obtain the deceleration section of the section, and the remaining section is taken as the constant speed section.

[0035] If the length of the section is greater than the final braking distance and less than the first distance, the difference between the length of the section and the final braking distance is obtained as the length difference.

[0036] The ratio between the length difference and the acceleration distance is obtained, and if the ratio is greater than 80%, the ending point of the section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to obtain the deceleration section of the section, and the remaining section is taken as the acceleration section without setting the constant speed section.

[0037] If the ratio is greater than 30% and less than 80%, the first operating speed is replaced by the second operating speed, the final braking distance is updated, the sum of the updated final braking distance and the acceleration distance is obtained as the second distance.

[0038] If the second distance is less than the length of the section, the starting point of the section is taken as the first base point, the acceleration distance is added to the first base point in the direction of the ending point to obtain the acceleration section of the section, the ending point of the section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to obtain the deceleration section of the section, and the remaining section is taken as the constant speed section.

[0039] If the second distance is greater than the length of the section, the ending point of the section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to obtain the deceleration section of the section, and the remaining section is taken as the acceleration section without setting the constant speed section.

[0040] If the ratio is less than 30%, the section is set as the constant speed section or the deceleration section.

[0041] If the length of the section is less than the final braking distance, the section is set as the constant speed section or the deceleration section.

[0042] Preferably, in step S5, the rules for controlling the speed of the unmanned forklift corresponding to the control are as follows:

[0043] When the unmanned forklift enters the acceleration section, the unmanned forklift is controlled to accelerate until the speed of the unmanned forklift reaches the second calculated speed;

[0044] When the unmanned forklift enters the uniform speed section, the unmanned forklift is controlled to maintain the speed of the previous control section;

[0045] When the unmanned forklift enters the deceleration section, the unmanned forklift is controlled to decelerate until the speed of the unmanned forklift reaches the preset speed.

[0046] An unmanned forklift handling system based on a synchronous motor uses an unmanned forklift handling method based on a synchronous motor, comprising a segmentation module, a first distance acquisition module, a second distance acquisition module, a control section determination module, and a speed control module;

[0047] The segmentation module is used to obtain a current conveying line, and road sections are segmented according to turning points, initial points, and destination points in the conveying line to obtain a plurality of road sections;

[0048] The first distance acquisition module is used to obtain the weight of the goods loaded on the unmanned forklift, and the final brake distance is determined according to the weight of the goods;

[0049] The second distance acquisition module is used to obtain the operating parameters of the synchronous motor of the unmanned forklift, and the acceleration distance is determined according to the operating parameters;

[0050] The control section determination module is used to divide the road sections according to the final brake distance and / or the acceleration distance, and determine the control sections in each road section, wherein the control sections include a deceleration section, an acceleration section, and a uniform speed section;

[0051] The speed control module is used to control the speed of the unmanned forklift when the unmanned forklift passes through different control sections.

[0052] Preferably, the first distance acquisition module includes an interval submodule, a preliminary distance submodule, an inertia coefficient submodule, and an adjustment module;

[0053] The interval submodule is used to select the speed interval of the unmanned forklift according to the weight of the goods;

[0054] The preliminary distance submodule is used to obtain the highest speed in the speed interval as a first calculated speed, obtain the friction coefficient of the tire of the unmanned forklift, and obtain a preliminary brake distance through the friction coefficient and the first calculated speed;

[0055] The inertia coefficient submodule is used to obtain the weight of the unmanned forklift and the goods as a total weight, and obtain an inertia adjustment coefficient according to the total weight, the friction coefficient, and the first calculated speed;

[0056] The adjusting module is configured to multiply the preliminary braking distance by the inertial adjusting coefficient to obtain the final braking distance.

[0057] Preferably, the second distance obtaining module comprises a selecting sub-module, an acceleration sub-module and a calculating sub-module.

[0058] The selecting sub-module is configured to obtain the lowest speed in the speed interval as the second operation speed.

[0059] The maximum torque of the motor is obtained.

[0060] The acceleration sub-module is configured to obtain the acceleration of the unmanned forklift by the total mass and the maximum torque.

[0061] The calculating sub-module is configured to obtain the acceleration distance by the acceleration and the second operation speed. The above technical solution has the following advantages or beneficial effects: in the present application, the acceleration distance is calculated, and then the road section is divided by the final braking distance and / or the acceleration distance, so as to determine which section needs to be accelerated and which section needs to be decelerated in the road section, thereby planning the running speed of the unmanned forklift in different control sections in the road section, ensuring stable transportation while ensuring the efficiency of transportation. BRIEF DESCRIPTION OF DRAWINGS

[0062] Fig. 1 is a flowchart schematic diagram of an embodiment of the method of the present application.

[0063] Fig. 2 is a structural schematic diagram of an embodiment of the system of the present application.

[0064] Fig. 3 is a setting diagram of a transportation route in an embodiment of the present application. DETAILED DESCRIPTION

[0065] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, in which the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0066] In the description of the embodiments of the present application, the terms "first", "second" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0067] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and are not to be construed as indicating or implying relative importance or a recitation that the indicated features are in any way crucial. Thus, a feature defined with "first", "second", etc. can include one or more of the features. In the description of the present application, unless otherwise stated, the meaning of "a plurality" is two or more. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

[0068] As shown in the figure, an unmanned forklift carrying method based on a synchronous motor includes the following steps: Figs. 1-3

[0069] Step S1: Obtain the current conveying line, and perform path segmentation according to the turning points, initial points and destination points in the conveying line to obtain a plurality of path segments;

[0070] Step S2: Obtain the weight of the goods loaded by the unmanned forklift, and determine the final braking distance according to the weight of the goods;

[0071] Step S3: Obtain the operating parameters of the synchronous motor of the unmanned forklift, and determine the acceleration distance according to the operating parameters;

[0072] Step S4: Divide the path segments according to the final braking distance and / or acceleration distance, and determine the control segments in each path segment, wherein the control segments include deceleration segments, acceleration segments and constant speed segments;

[0073] Step S5: When the unmanned forklift passes through different control segments, the speed of the unmanned forklift is controlled correspondingly.

[0074] In order to avoid the unmanned forklift from throwing the goods out due to inertia when turning, the conveying line is preferentially segmented in the present application, as shown in the figure Fig. 3 ​As shown in the figure, A and F points are the initial point and the destination point respectively, and B, C and D points are turning points, at this time, adjacent points are combined to obtain the corresponding road section. For example, A and B points are combined to obtain the first road section AB, then B and C points are combined to obtain the second road section BC, and the road sections CD, DE and EF are obtained in turn. Because the inertia of the brake is different after loading the goods of different weights, the weight of the goods loaded by the unmanned forklift needs to be obtained, the brake distance is determined through the weight of the goods, so that the unmanned forklift can brake in advance, and when the unmanned forklift reaches the turning point to turn, the speed of the unmanned forklift will not cause the goods to be thrown out. In addition, because the length of some road sections is long, if the goods are transported at a low speed all the time, the transportation speed will be affected, therefore, the acceleration distance is also calculated in the application, and then the road section is divided through the final brake distance and / or the acceleration distance, it is determined that which section in the road section needs to be accelerated and which section needs to be decelerated, so that the running speed of the unmanned forklift in different control sections in the road section is planned, the stable transportation is ensured, and the transportation efficiency is also ensured.

[0075] Preferably, the step S2 of obtaining the final brake distance is as follows:

[0076] Step S21: according to the weight of the goods, the speed interval of the unmanned forklift is selected;

[0077] Step S22: the highest speed in the speed interval is obtained as a first calculation speed, the friction coefficient of the tire of the unmanned forklift is obtained, and the preliminary brake distance is obtained through the friction coefficient and the first calculation speed;

[0078] Step S23: the weight of the unmanned forklift and the goods is obtained as a total weight, and the inertia adjustment coefficient is obtained according to the total weight, the friction coefficient and the first calculation speed;

[0079] Step S24: the final brake distance is obtained by multiplying the inertia adjustment coefficient by the preliminary brake distance.

[0080] Before obtaining the final brake distance, it is necessary to determine the safe speed of the unmanned forklift of this type when transporting goods of different weights through multiple groups. Because it is limited by the environment, the speed is usually a speed interval, for example, when the goods are 80-100 kg, the speed of 10-15 km / h can be used for transportation. After the speed interval is selected, the highest speed in the interval is used to obtain the preliminary brake distance, because the highest speed is used for calculation, the length of the preliminary brake distance can be increased to ensure that the unmanned forklift has a sufficient distance to decelerate.

[0081] But due to the influence of inertia, even if the preliminary braking distance is increased, the running speed of the unmanned forklift is fast when turning, so that the goods fall off. Therefore, the present application considers the influence of inertia, calculates the inertia adjustment coefficient to adjust the preliminary braking distance, so as to ensure that there is enough length to give the unmanned forklift to slow down.

[0082] Preferably, the specific formula for obtaining the preliminary braking distance in step S22 is as follows:

[0083] ;

[0084] Wherein S1 is the preliminary braking distance, is the first operation speed, g is the acceleration of gravity, is the friction coefficient;

[0085] The specific formula for obtaining the inertia adjustment coefficient in step S23 is as follows:

[0086] ;

[0087] Wherein C is an error correction coefficient greater than 1, a1, a2, a3 are total weight adjustment factor, speed adjustment factor and friction coefficient adjustment factor respectively, and m is the total weight.

[0088] Preferably, the step of determining the acceleration distance in step S3 is as follows:

[0089] Step S31: obtaining the lowest speed in the speed interval as the second operation speed;

[0090] Obtaining the maximum torque of the motor;

[0091] Step S32: obtaining the acceleration of the unmanned forklift by the total mass and the maximum torque;

[0092] Step S33: obtaining the acceleration distance by the acceleration and the second operation speed;

[0093] Wherein the acceleration is obtained by the following formula:

[0094] ;

[0095] The formula for obtaining the acceleration distance is as follows:

[0096] ;

[0097] Wherein F is the maximum torque, and V2 is the second operation speed.

[0098] The second transport speed is the speed of the unmanned forklift after acceleration. When determining the acceleration distance, the lowest speed in the speed range is used as the second calculation speed, because the ground friction in the actual environment may be smaller than that in the test environment. If the first calculation speed is used to calculate the acceleration distance, the transport speed of the unmanned forklift after acceleration will be greater than the first calculation speed, so that there is not enough distance to decelerate, affecting the stability of transportation. If the second calculation speed is used to calculate the acceleration distance, the speed of the unmanned forklift after acceleration can be reduced. The unmanned forklift can reduce the speed in the deceleration section to a speed that can be stably turned.

[0099] Preferably, the rules for determining the deceleration section, the acceleration section and the constant speed section in step S4 are as follows:

[0100] The sum of the final braking distance and the acceleration distance is obtained as the first distance;

[0101] If the length of the road section is greater than the first distance, the starting point of the road section is taken as the first base point, the acceleration distance is added to the first base point in the direction of the terminal point to form the acceleration section of the road section, the terminal point of the road section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to form the deceleration section of the road section, and the remaining road section is taken as the constant speed section;

[0102] If the length of the road section is greater than the final braking distance and less than the first distance, the difference between the length of the road section and the final braking distance is obtained as the length difference;

[0103] The ratio between the length difference and the acceleration distance is obtained, if the ratio is greater than 80%, the terminal point of the road section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to form the deceleration section of the road section, and the remaining road section is taken as the acceleration section, without setting the constant speed section;

[0104] If the ratio is greater than 30% and less than 80%, the first calculation speed is replaced by the second calculation speed, the final braking distance is updated, and the sum of the updated final braking distance and the acceleration distance is obtained as the second distance;

[0105] If the second distance is less than the length of the road section, the starting point of the road section is taken as the first base point, the acceleration distance is added to the first base point in the direction of the terminal point to form the acceleration section of the road section, the terminal point of the road section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to form the deceleration section of the road section, and the remaining road section is taken as the constant speed section;

[0106] If the second distance is greater than the length of the road section, the terminal point of the road section is taken as the second base point, the final braking distance is added to the second base point in the direction of the starting point to form the deceleration section of the road section, and the remaining road section is taken as the acceleration section, without setting the constant speed section;

[0107] If the proportion is less than 30%, the road section is set as a constant speed section or a deceleration section.

[0108] If the length of a road segment is less than the final braking distance, then the road segment is designated as a constant speed segment or a deceleration segment.

[0109] like Fig. 3 As shown, in road segment AB, point A will be the starting point of the road segment, and point B will be the ending point of the road segment. The length of road segment AB is greater than the first distance. At this time, point A will be used as the first base point, and the acceleration distance will be increased from the first base point to point B to obtain the acceleration segment. At the same time, point B will be used as the second base point, and the final braking distance will be increased from the second base point to point A to obtain the deceleration segment. The segment between the acceleration segment and the deceleration segment is the constant speed segment.

[0110] When the length of the road segment is greater than the final braking distance but less than the first distance, it means that the unmanned forklift has not yet accelerated to the second operating speed and needs to decelerate. Therefore, when this happens, the difference between the road segment length and the final braking distance will be obtained first as the length difference. The ratio between the length difference and the acceleration distance will be obtained. If the ratio is greater than 80%, it means that there is enough distance for the unmanned forklift to accelerate and increase the transportation speed of the unmanned forklift. However, in order to ensure a smooth turn, the length of the deceleration segment will be maintained, and the remaining road segment will be used as the acceleration segment for acceleration operation.

[0111] When the ratio is greater than 30% but less than 80%, even if the remaining road segment accelerates, its speed will not reach the second calculation speed. This is because the initial final braking distance is calculated using the first calculation speed, allowing for a margin of error. However, when acceleration fails to reach the second transport speed, this margin of error becomes useless. Therefore, this invention uses the second calculation speed instead of the first calculation speed to update the final braking distance. By shortening the length of the deceleration section, the length of the remaining road segment is increased, and then the corresponding road segment is divided. This improves the transport efficiency of the unmanned forklift.

[0112] When the ratio is less than 30%, the acceleration effect of the automated forklift is minimal. In this case, the automated forklift will not accelerate, and the remaining road segment will be designated as a constant speed segment or a deceleration segment. Similarly, when the length of the road segment is less than the final braking distance, the acceleration effect of the automated forklift is minimal, and the road segment will be designated as a constant speed segment or a deceleration segment.

[0113] Preferably, in step S5, the specific rules for controlling the speed of the unmanned forklift are as follows:

[0114] When the unmanned forklift enters the acceleration phase, control the unmanned forklift to accelerate until the speed of the unmanned forklift reaches the second calculation speed.

[0115] When the unmanned forklift enters the uniform speed section, the speed of the unmanned forklift in the previous control section is kept;

[0116] When the unmanned forklift enters the deceleration section, the unmanned forklift is controlled to decelerate until the speed of the unmanned forklift reaches the preset speed.

[0117] The preset speed is the speed at which the unmanned forklift can stably turn, which is a preset value, generally set to 5-7 km / h, and can be selected according to different weights.

[0118] The uniform speed section is to keep the speed of the previous control section as the speed of the uniform speed section, if the previous section is an acceleration section, the speed reached in the acceleration section is kept as the speed of the uniform speed section. If the previous section is a deceleration section, the preset speed is kept as the speed of the uniform speed section.

[0119] An unmanned forklift handling system based on a synchronous motor uses the unmanned forklift handling method based on the synchronous motor, comprising a segmentation module, a first distance acquisition module, a second distance acquisition module, a control section determination module, and a speed control module.

[0120] The segmentation module is used to obtain a current conveying line, and the route section is segmented according to the turning point, initial point and destination point in the conveying line to obtain a plurality of route sections.

[0121] The first distance acquisition module is used to obtain the weight of the goods loaded on the unmanned forklift, and the final brake distance is determined according to the weight of the goods.

[0122] The second distance acquisition module is used to obtain the operating parameters of the synchronous motor of the unmanned forklift, and the acceleration distance is determined according to the operating parameters.

[0123] The control section determination module is used to divide the route section according to the final brake distance and / or acceleration distance, and determine the control section in each route section, wherein the control section includes a deceleration section, an acceleration section and a uniform speed section.

[0124] The speed control module is used to control the speed of the unmanned forklift when the unmanned forklift passes through different control sections.

[0125] Preferably, the first distance acquisition module includes an interval submodule, a preliminary distance submodule, an inertia coefficient submodule and an adjustment module.

[0126] The interval submodule is used to select the speed interval of the unmanned forklift according to the weight of the goods.

[0127] The preliminary distance submodule is used to obtain the highest speed in the speed interval as the first calculation speed, obtain the friction coefficient of the tire of the unmanned forklift, and obtain the preliminary brake distance through the friction coefficient and the first calculation speed.

[0128] The inertia coefficient submodule is configured to acquire the weight of the unmanned forklift and the goods as a total weight, and acquire an inertia adjustment coefficient according to the total weight, a friction coefficient, and a first calculation speed;

[0129] The adjustment module is configured to obtain the final brake distance by multiplying the preliminary brake distance by the inertia adjustment coefficient.

[0130] Preferably, the second distance acquisition module comprises a selection submodule, an acceleration submodule, and a calculation submodule.

[0131] The selection submodule is configured to acquire the lowest speed in the speed interval as a second calculation speed.

[0132] The maximum torque of the motor is acquired.

[0133] The acceleration submodule is configured to acquire the acceleration of the unmanned forklift by the total mass and the maximum torque.

[0134] The calculation submodule is configured to acquire the acceleration distance by the acceleration and the second calculation speed.

[0135] Although the embodiments of the present application have been shown and described above, it should be understood by those skilled in the art that the above embodiments are exemplary and are not to be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements, and variations to the above embodiments within the scope of the present application.

Claims

1. A method for unmanned fork truck handling based on a synchronous electric machine, characterized in that, The method comprises the following steps: Step S1: obtaining a current conveying line, segmenting a road section according to a turning point, an initial point and a destination point in the conveying line to obtain a plurality of road sections; Step S2: obtaining the weight of the goods loaded by the unmanned forklift, determining a final braking distance according to the weight of the goods; Step S3: obtaining the running parameters of the synchronous motor of the unmanned forklift, determining an acceleration distance according to the running parameters; Step S4: dividing the road section according to the final braking distance and / or the acceleration distance to determine a control section in each road section, wherein the control section comprises a deceleration section, an acceleration section and a constant speed section; Step S5: when the unmanned forklift passes through different control sections, corresponding control is performed on the speed of the unmanned forklift; The step of obtaining the final braking distance in step S2 is as follows: Step S21: selecting a speed interval of the unmanned forklift according to the weight of the goods; Step S22: obtaining the highest speed in the speed interval as a first calculation speed, obtaining the friction coefficient of the tire of the unmanned forklift, and obtaining a preliminary braking distance through the friction coefficient and the first calculation speed; Step S23: obtaining the weight of the unmanned forklift and the goods as a total weight, and obtaining an inertia adjustment coefficient according to the total weight, the friction coefficient and the first calculation speed; Step S24: multiplying the inertia adjustment coefficient by the preliminary braking distance to obtain the final braking distance; The specific formula for obtaining the preliminary braking distance in step S22 is as follows: ； where S1 is a preliminary braking distance, is a first operating speed, g is the acceleration of gravity, is a friction coefficient; The specific formula for obtaining the inertia adjustment coefficient in step S23 is as follows: ； where C is an error correction factor greater than 1, a1, a2, a3 are total weight adjustment factor, speed adjustment factor and friction coefficient adjustment factor respectively, m is total weight, is the first operating speed; The rules for determining the deceleration section, the acceleration section and the constant speed section in step S4 are as follows: Obtain the sum of the final braking distance and the acceleration distance as a first distance; If the length of the road section is greater than the first distance, take the starting point of the road section as a first base point, add the acceleration distance to the first base point in the direction of the terminal point to obtain the acceleration section of the road section, take the terminal point of the road section as a second base point, add the final braking distance to the second base point in the direction of the starting point to obtain the deceleration section of the road section, and the remaining road section is the constant speed section; If the length of the road section is greater than the final braking distance and less than the first distance, obtain the difference between the length of the road section and the final braking distance as a length difference; Obtain the ratio between the length difference and the acceleration distance, if the ratio is greater than 80%, take the terminal point of the road section as a second base point, add the final braking distance to the second base point in the direction of the starting point to obtain the deceleration section of the road section, and the remaining road section is the acceleration section, without setting the constant speed section; If the ratio is greater than 30% and less than 80%, replace the first calculation speed with a second calculation speed, update the final braking distance, obtain the sum of the updated final braking distance and the acceleration distance as a second distance; Determine whether the second distance is less than the length of the road section, if yes, take the starting point of the road section as a first base point, add the acceleration distance to the first base point in the direction of the terminal point to obtain the acceleration section of the road section, take the terminal point of the road section as a second base point, add the final braking distance to the second base point in the direction of the starting point to obtain the deceleration section of the road section, and the remaining road section is the constant speed section; If greater, then the end point of the road section is taken as the second base point, the second base point is added to the final braking distance in the starting point direction to form the deceleration section of the road section, the remaining road section is taken as the acceleration section, and no uniform speed section is set; If the ratio is less than 30%, the road section is set as a uniform speed section or a deceleration section; If the length of the road section is less than the final braking distance, the road section is set as a uniform speed section or a deceleration section.

2. The unmanned fork truck handling method based on synchronous motor according to claim 1, characterized in that, In the step S5, the rules for controlling the speed of the unmanned forklift corresponding to the control section are as follows: When the unmanned forklift enters the acceleration section, the unmanned forklift is controlled to accelerate until the speed of the unmanned forklift reaches the second calculated speed; When the unmanned forklift enters the uniform speed section, the unmanned forklift is controlled to maintain the speed of the previous control section; When the unmanned forklift enters the deceleration section, the unmanned forklift is controlled to decelerate until the speed of the unmanned forklift reaches the preset speed.

3. A synchronous motor based unmanned forklift truck handling system using the synchronous motor based unmanned forklift truck handling method of any one of claims 1 to 2, characterized in that, Comprise: The segmentation module, the first distance acquisition module, the second distance acquisition module, the control section determination module and the speed control module; The segmentation module is used for obtaining a current conveying line, segmenting a road section according to a turning point, an initial point and a destination point in the conveying line, and obtaining a plurality of road sections; The first distance acquisition module is used for acquiring the weight of the goods loaded on the unmanned forklift, and determining the final braking distance according to the weight of the goods; The second distance acquisition module is used for acquiring the operating parameters of the synchronous motor of the unmanned forklift, and determining the acceleration distance according to the operating parameters; The control section determination module is used for dividing the road section according to the final braking distance and / or the acceleration distance, and determining the control section in each road section, wherein the control section comprises a deceleration section, an acceleration section and a uniform speed section; The speed control module is used for controlling the speed of the unmanned forklift corresponding to the control section when the unmanned forklift passes through different control sections.

4. The synchronous motor based unmanned fork truck handling system of claim 3 wherein, The first distance acquisition module comprises an interval submodule, a preliminary distance submodule, an inertia coefficient submodule and an adjustment module; The interval submodule is used for selecting a speed interval of the unmanned forklift according to the weight of the goods; The preliminary distance submodule is used for acquiring the highest speed in the speed interval as a first calculated speed, acquiring the friction coefficient of the tire of the unmanned forklift, and acquiring a preliminary braking distance through the friction coefficient and the first calculated speed; The inertia coefficient submodule is used for acquiring the weight of the unmanned forklift and the goods as a total weight, and acquiring an inertia adjustment coefficient according to the total weight, the friction coefficient and the first calculated speed; The adjustment module is used for multiplying the inertia adjustment coefficient by the preliminary braking distance to obtain the final braking distance.

5. The synchronous motor based unmanned fork truck handling system according to claim 3, wherein, The second distance acquisition module comprises a selection submodule, an acceleration submodule and a calculation submodule; The selection submodule is used for acquiring the lowest speed in the speed interval as a second calculated speed; The maximum torque of the motor is acquired; The acceleration submodule is used for acquiring the acceleration of the unmanned forklift through the total mass and the maximum torque; The calculation submodule is used for acquiring the acceleration distance through the acceleration and the second calculated speed.

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