Automatic leveling control method for preventing deformation and distortion of platform

Abstract

The invention belongs to the field of automatic control, and relates to an automatic leveling control method for preventing deformation and distortion of a platform. A new landing detection and sectional type real-time proportional approximation leveling method is adopted, in the leveling process, landing detection of the supporting leg is achieved through bearing moment and no-load moment data fed back by a leveling leg motor; the highest point is judged according to horizontal angle signals, fed back by a horizontal detector, of the X axis and the Y axis, the other three leveling supporting legs run according to different proportional speeds and approach the highest point, and the equipment vehicle carrying platform tracks the horizontal plane in real time and gradually approaches the horizontal plane; in the leveling process, different intervals are divided according to angle errors, the running speed of the leveling supporting leg is redistributed and adjusted in each interval, the speed is changed from high to low, and leveling is changed from coarse adjustment to fine adjustment until the system is leveled. According to the method, the problems that the vehicle is deformed and distorted, virtual legs are prone to occurring, and the system is unstable are solved, and the method has wide application prospects in the field.

Description

Technical Field

[0001] The invention belongs to the field of automatic control and relates to an automatic leveling control method for preventing a platform from being deformed and twisted. Background Art

[0002] In order to meet the needs of modern warfare, more and more radar equipment, missile or rocket launcher vehicles have adopted leveling systems, which can improve the equipment's anti-overturning ability on the one hand, and improve the system's maneuverability and accuracy on the other. The traditional leveling system uses mechanical leveling, manually adjusting the jack, and repeatedly operating each jack to make the vehicle reach a horizontal state. This method takes a long time to level and has low accuracy. In recent years, most equipment platforms have adopted automatic leveling systems, mainly electromechanical automatic leveling systems and hydraulic leveling systems, which greatly shorten the leveling time and improve the leveling accuracy.

[0003] Electromechanical leveling systems and hydraulic leveling systems each have their own advantages and disadvantages. The hydraulic system is small in size, light in weight, compact in structure, runs smoothly, can effectively buffer external impact forces, and has strong load-bearing capacity. Large-tonnage leveling systems generally use hydraulics, but the hydraulic system has complex pipelines and many joints, and it is difficult to avoid leakage over time. The hydraulic system is sensitive to temperature changes, and the hydraulic oil is highly elastic. It cannot guarantee accurate positioning after bearing loads, and the system maintenance is difficult. In recent years, servo control technology and sensor technology have developed rapidly. The use of servo-driven electromechanical leveling systems has the advantages of high precision, good stability, and high speed.

[0004] The electromechanical four-point support automatic leveling system consists of a control cabinet (including a leveling controller, four servo drives), a level detector, four sets of leveling legs, etc. There are generally two methods for four-point automatic leveling: two-point leveling and multi-point adjustment. The two-point leveling method is to level the X-axis and the Y-axis separately, that is, first adjust the two legs of the X-axis to make the axis horizontal, and then adjust the two legs of the Y-axis to make the axis horizontal, and adjust repeatedly until the horizontal angles of both the X-axis and the Y-axis are zero. This method has a simple algorithm, but the adjustment time is long. At the same time, during the leveling process, each leg is unevenly stressed, the body deformation and distortion are large, and "virtual legs" are prone to occur, which is not conducive to system stability.

[0005] The multi-point leveling method is: based on the horizontal angle signals of the X-axis and Y-axis fed back by the horizontal detector, the highest point is determined, and then the other legs are driven to approach the highest point at the same time. This leveling method has the advantages of fast speed and the vehicle body is not easy to overturn. However, if the vehicle body is very rigid, a "false leg" phenomenon may occur. At the same time, multiple adjustments will be made during the leveling process, and the vehicle body is prone to abnormal noises, indicating that the vehicle body is severely twisted and deformed during the leveling process, which will reduce the life cycle of the structural parts on the vehicle body.

[0006] During the automatic leveling process, the leveling legs are extended, and after all of them are on the ground and subjected to force, the automatic leveling control process begins. There are generally three methods for detecting the leveling leg landing: 1. Real-time detection of the leveling leg motor output torque during the leveling leg extension process. When the torque reaches the preset threshold, the action stops, and the leveling leg is on the ground; 2. A weighing sensor is installed at the lower end of the leveling leg. When the gravity fed back by the weighing sensor reaches the set threshold, the action stops, and the leveling leg is on the ground; 3. A slider limit mechanism is installed at the lower end of the leveling leg. When the leveling leg is on the ground and subjected to force, the slider moves up from the bottom of the mechanism along the slide slot. When the upper limit sensor detects the slider, the action stops, and the leveling is on the ground. These three methods have their own advantages and disadvantages. The first detection method is easily affected by the external environment, especially when the temperature changes. The leveling leg torque will increase as the temperature decreases. In order to increase the reliability of landing detection, the landing torque threshold needs to be modified, which increases the load and uncertainty of the system. Although the second and third methods overcome the influence of external environmental factors, they increase the complexity and cost of system design. When the feedback device fails or the cable is disconnected, resulting in no signal feedback, it may cause misjudgment of landing detection. Summary of the invention

[0007] In view of the shortcomings of the background technology, the present invention provides an automatic leveling control method for preventing platform deformation and distortion. The present invention adopts a new landing detection and segmented real-time proportional approximation leveling method: during the leveling process, the load-bearing torque and no-load torque data fed back by the leveling leg motor are used to realize the leg landing detection; according to the horizontal angle signals of the X-axis and Y-axis fed back by the horizontal detector, the highest point is judged, and the other three leveling legs run at different proportional speeds to approach the highest point, and the equipment vehicle platform tracks and gradually approaches the horizontal plane in real time; during the leveling process, different intervals are divided according to the angle error, and the running speed of the leveling legs is redistributed and adjusted in each interval, the speed changes from fast to slow, and the leveling changes from coarse adjustment to fine adjustment until the system is leveled; during the leveling process, the load-bearing torque and no-load torque data are used to judge the "virtual leg" situation of the leveling legs, and the leg operation is controlled to eliminate the "virtual leg" problem. This method realizes the requirements of fast, high-precision, low-cost, and high-reliability automatic leveling of the equipment vehicle, solves the problems of vehicle deformation and distortion, easy occurrence of "virtual legs", and system instability, and has broad application prospects in this field.

[0008] The technical solution of the present invention is: an automatic leveling control method for preventing platform deformation and distortion, characterized in that it includes the following steps:

[0009] Step 1: After the leg extension phase is running stably, read the running torque value of the leveling leg and record it as the leveling leg no-load torque T 0-1 , T 0-2 , T 0-3 , T 0-4 ;

[0010] Step 2: Torque detection during the landing phase; after the leg extension phase is completed, read the real-time torque data T of the leg extension motor during the leveling leg extension process. r-1 , T r-2 , T r-3 , T r-4 , calculate the difference ΔT1, ΔT2, ΔT3, ΔT4 with the no-load moment, when ΔT is greater than the preset moment threshold, the leg extension action stops and the leg lands, until all four legs land;

[0011] Step 3: According to the horizontal angle signals of the X-axis and the Y-axis fed back by the horizontal detector, determine the highest point of the supporting leg;

[0012] Step 4: Enter the leveling stage, set the leveling speed u and the horizontal angle error δ0, the actual leveling speed of the leveling leg with the largest operating height is equal to the leveling speed u, and the actual leveling speeds of the other two leveling legs are obtained by multiplying the ratio of the required operating height of the legs to the operating height of the leg with the largest operating height by the leveling speed u; the three legs are leveled according to their respective actual leveling speeds; the staged leveling end condition is when the real-time horizontal angle error δ is less than the horizontal angle error δ0;

[0013] Step 5: If the horizontal angle error δ after leveling in step 4 cannot meet the requirements, reduce the leveling speed u and the horizontal angle error δ0, and then continue to execute step 4 until the final leveling requirements are met; if the horizontal angle error δ meets the requirements, the automatic leveling is completed.

[0014] The beneficial effects of the present invention are: first, the multi-point segmented approximation method is used for leveling, which effectively avoids the complex algorithm of angle coupling / decoupling between the X-axis and the Y-axis, the four legs are evenly stressed, the deformation and distortion of the vehicle body are small, the leveling speed is fast, the accuracy is high, and the system runs smoothly; second, the landing detection is simple and reliable, and the difference between the no-load torque and the load torque feedback from the leveling leg motor is used to judge the landing force condition. There is no need to install other detection mechanisms, which reduces costs and avoids the problem of "empty legs"; third, during operation, the operating parameters of the four legs are monitored in real time to improve the reliability and safety of the leveling system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of automatic leveling system installed on equipment.

[0016] Figure 2 Automatic leveling system block diagram.

[0017] Figure 3 Schematic diagram of the model based on the vehicle platform. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the accompanying drawings.

[0019] like Figure 1 The figure shows the schematic diagram of the automatic leveling system installed on the radar vehicle. The radar vehicle in the present invention weighs more than 20 tons, and the leveling accuracy of the radar vehicle is required to be no more than 3', and the deformation and distortion of the structure are required to be reduced during the automatic leveling process to avoid affecting other radar equipment. The platform rigidity of the radar vehicle is relatively strong, and the previous multi-point leveling method may cause the "false leg" phenomenon.

[0020] The control system block diagram is as follows Figure 2 As shown in the figure, the system consists of a leveling controller, four servo drives, four leveling legs (including servo motors, screw drive mechanisms), limit sensors, and a horizontal detector. The leveling controller mainly completes the system control algorithm. The controller continuously samples the X / Y axis angle data of the horizontal detector and the speed, position, and torque information of the leveling leg motors fed back by the four servo drives. According to the running load and no-load torque values ​​of the leveling legs, the force of the legs touching the ground is judged. According to the X / Y axis angle information, the automatic leveling algorithm is adjusted in real time, so that the system can complete automatic leveling quickly and accurately. The servo drive and motor are actuators, and the limit sensor is a safety limit detection device.

[0021] After receiving the leveling control command, the controller controls the four drivers to drive their respective leveling legs to extend at high speed. At this time, the controller reads the no-load torque of the leveling leg, and detects the operating torque in real time during the leveling and leg extension process. When it is detected that the difference between the operating torque and the no-load torque reaches the preset threshold, the leveling leg is landed and the automatic leveling process begins. According to the horizontal angle signals of the X-axis and Y-axis fed back by the horizontal detector, the highest point is determined, and the other three leveling legs run at different proportional speeds and approach the highest point. The equipment carrier platform tracks and gradually approaches the horizontal plane in real time. During the leveling process, different intervals are divided according to the angle error, and the running speed of the leveling legs is redistributed and adjusted in each interval, from fast to slow, and the leveling is from coarse adjustment to fine adjustment, until the system is leveled. During the leveling process, the torque data of the three leg motors are detected in real time. If the difference between the operating torque and the no-load torque is less than the set threshold, the leveling leg is a "virtual leg" and continues to be extended until the torque difference reaches the threshold to eliminate the "virtual leg" problem.

[0022] An automatic leveling control method for preventing platform deformation and distortion of the present invention comprises the following steps:

[0023] Step 1: Extend the four leveling legs. After the operation is stable, read the running torque value of the leveling leg motor at this time, which is recorded as the leveling leg no-load torque T 0-1 , T 0-2 , T 0-3 , T 0-4If the length of the leveling leg is 500mm, and the length of the leveling leg is between 0 and 200mm to ensure that it will not fall to the ground, then the leg extension stage is between 0 and 200mm. In the leg extension process, the no-load moment T can be measured between 100mm and 200mm. 0-1 , T 0-2 , T 0-3 , T 0-4 In this way, the measured no-load torque is relatively stable through the operation from 0 to 100 mm. Generally, in order to ensure the operating speed, the extension speed is faster.

[0024] Step 2: Torque detection landing stage. After the leg extension stage is completed, the torque detection landing stage begins. The torque detection landing stage is between 200mm and 500mm. During this stage, the real-time torque data T of the leg extension motor is continuously read during the leveling leg extension process. r-1 , T r-2 , T r-3 , T r-4 , calculate the difference ΔT1, ΔT2, ΔT3, ΔT4 with the no-load moment, and the difference ΔT1 of the no-load moment of leg 1 is the moment data T r-1 Subtract no-load moment T 0-1， The other legs are the same, that is, the difference ΔT2 of the no-load moment of leg 2 is the moment data T r-2 Subtract no-load moment T 0-2， When ΔT is greater than the preset torque threshold, the leg extension stops and the leg lands, until all four legs land. During the landing detection phase, if the torque of a leg does not reach the preset threshold until the stroke reaches the longest value, the leg extension fails to land, and subsequent leveling cannot be performed.

[0025] In this embodiment, according to the distribution of the center of gravity of the radar vehicle and the installation position of the equipment, in consideration of minimizing the deformation of the vehicle body, a half-tire grounding method is adopted during leveling. During the debugging process, the force data of each leg outstretched after landing is monitored, and the torque threshold of each leg outstretched motor is selected as 2.5Nm, 2.8Nm, 2.6Nm, and 3.1Nm, respectively. That is, the torque threshold of each leg outstretched motor can be set to different values ​​according to actual conditions.

[0026] Step 3: According to the horizontal angle signals of the X-axis and Y-axis fed back by the horizontal detector, determine the highest support leg and calculate the required operating heights of the other three support legs. Figure 3 As shown, a model between the platform and the horizontal plane is established according to the installation form of the horizontal detector on the radar vehicle.

[0027] When the radar vehicle is not leveled, assume that leg 2 is the highest point, and the platform surface is shown in 3, where 1234 is the platform surface, and a horizontal plane is made through leg 2, that is, 1′2 3′4′ is the platform surface in a horizontal state, then it can be approximately considered that 11′⊥21′, 33′⊥23′. Assume that the spacing between platform leg 1 and leg 2, and between leg 2 and leg 3 is L respectively. a , L b When leveling, the required operating heights of leg 1, leg 3, and leg 4 relative to leg 2 are:

[0028] h1=L a sinα (1)

[0029] h3=L b sinβ (2)

[0030] h4=L a sinα+L b sinβ (3)

[0031] In the actual leveling process, the platform will inevitably deform and the leveling legs will slide sideways. Therefore, the operating height of the three legs calculated according to the above formula is not accurate. It can only reflect a stroke ratio relationship of the legs in a relatively short period of time. Based on this situation, the entire leveling process is divided into multiple intervals. In each interval, the highest point is kept stationary, and the other three legs are operated according to the speed relationship of h1:h3:h4, so that the low point catches up with the high point, thereby achieving the purpose of fast and accurate leveling of the platform.

[0032] Step 4, entering the leveling stage, first determine the leveling speed u and the horizontal angle error δ0. The actual leveling speed of the leveling leg with the largest operating height is equal to the leveling speed u, and the actual leveling speeds of the other two leveling legs are calculated according to the required operating height.

[0033] In the present invention, the three legs that need to be raised run at different proportional speeds and approach the highest point.

[0034] The horizontal angle error target value δ0 is set to 20′. Assuming that leg 2 is the highest point, the proportional relationship between the control command signals of the three legs is:

[0035] u1:u3:u4=h1:h3:h4 (4)

[0036] Since the lowest point is leg 4, the speed control command of leg 4 is the largest. Let u4 = u, then

[0037]

[0038]

[0039] Leveling is performed according to the relationship among u1, u2 and u4, and when the real-time horizontal angle error δ is less than δ0, it is used as the end condition of staged leveling. In this way, in the leveling process of the present invention, three relatively low points approach the highest point at different speeds, so that there is no obvious abnormal sound on the vehicle body during the leveling process of the present invention, indicating that the structural deformation on the vehicle body is effectively corrected, thereby protecting the structural parts on the vehicle body and improving reliability; at the same time, three points are aligned to the highest point at different speeds.

[0040] In order to eliminate the "false leg" phenomenon, the end condition of leveling of the present invention can also add a threshold judgment, set the leveling stage torque threshold ΔT, when the real-time horizontal angle error δ is less than δ0, if the ΔT of a certain leg is less than the setting, then the leveling leg is "false leg", continue to extend the leg, and the other legs stop running until the difference in the leg torque reaches the threshold, thereby eliminating the "false leg" problem. During the leg extension process, the horizontal angle error δ can be monitored in real time. If the horizontal angle error δ is too large, a fault can be reported and the movement of all legs can be stopped. After adopting this method, the situation of false legs after leveling is completely eliminated.

[0041] Step 5: If the horizontal angle error δ does not meet the requirement, reduce the leveling speed u and the horizontal angle error δ0, and then continue to execute step 4 until the final leveling requirement is met; if the horizontal angle error δ meets the requirement, the automatic leveling is completed.

[0042] For example, when step 4 is executed for the first time, the leveling speed u is 2000 rpm, the horizontal angle error δ0 is 20', and high-speed leveling is achieved; when step 4 is executed for the second time, the leveling speed u is 500 rpm, the horizontal angle error δ0 is 10', and relatively high-speed leveling is achieved; when step 4 is executed for the third time, the leveling speed u is 100 rpm, the horizontal angle error δ0 is 3', and high-precision leveling is achieved. In this way, the leveling speed can be increased while taking into account the leveling accuracy.

[0043] All control algorithms of the present invention are completed in the leveling controller, and a communication interface is reserved, so that various parameters can be flexibly modified through a computer to meet the leveling control system of different loads, which is conducive to promotion and application.

Claims

1. An automatic leveling control method for preventing platform deformation and distortion, characterized in that: The following steps are involved: Step 1: After the leg extension phase is running stably, read the running torque value of the leveling leg and record it as the leveling leg no-load torque T 0-1 、T 0-2 、T 0-3 、T 0-4 ; Step 2: Torque detection during the landing phase; after the leg extension phase is completed, read the real-time torque data T of the leg extension motor during the leveling leg extension process. r-1 、T r-2 、T r-3 、T r-4 , calculate the difference ΔT1, ΔT2, ΔT3, ΔT4 with the no-load moment, when ΔT is greater than the preset moment threshold, the leg extension action stops and the leg lands, until all four legs land; Step 3: According to the horizontal angle signals of the X-axis and the Y-axis fed back by the horizontal detector, determine the highest point of the supporting leg; Step 4: Enter the leveling stage, set the leveling speed u and the horizontal angle error δ0, the actual leveling speed of the leveling leg with the largest operating height is equal to the leveling speed u, and the actual leveling speeds of the other two leveling legs are obtained by multiplying the ratio of the required operating height of the legs to the operating height of the leg with the largest operating height by the leveling speed u; the three legs are leveled according to their respective actual leveling speeds; the staged leveling end condition is when the real-time horizontal angle error δ is less than the horizontal angle error δ0; Step 5: If the horizontal angle error δ after leveling in step 4 cannot meet the requirements, reduce the leveling speed u and the horizontal angle error δ0, and then continue to execute step 4 until the final leveling requirements are met; if the horizontal angle error δ meets the requirements, the automatic leveling is completed.

2. The automatic leveling control method for preventing platform deformation and distortion according to claim 1, characterized in that: The leveling end condition also includes a threshold judgment. When the real-time horizontal angle error δ is less than the horizontal angle error δ0, if the difference ΔT of the no-load torque of a certain leg is less than the torque threshold, the leg continues to be extended, and the other legs stop running until the difference of the no-load torque of the legs is greater than or equal to the torque threshold.

3. The automatic leveling control method for preventing platform deformation and distortion according to claim 1 or 2, characterized in that: When leg 2 is at the highest point, leg 1, leg 3, and leg 4 need to operate at heights h1, h3, and h4; then h4 corresponds to the leveling speed u4 of leg 4, which is equal to the leveling speed u, and the corresponding relationship between the leveling speeds u1, u3 and h4 of leg 1 and leg 3 is: u1:u3:u4=h1:h3:h4.

4. The automatic leveling control method for preventing platform deformation and distortion according to claim 1 or 2, characterized in that: The difference of the leg unloaded moment is the real-time moment data T r-1 Subtract no-load moment T 0-1 .

5. The automatic leveling control method for preventing platform deformation and distortion according to claim 1 or 2, characterized in that: It also includes a control system, which includes a leveling controller, four servo drives, four leveling legs, and a horizontal detector. The leveling controller completes the system control algorithm. The controller continuously samples the X / Y-axis angle data of the horizontal detector and the speed, position and torque information of the leveling leg motors fed back by the four servo drives. According to the running load and no-load torque values ​​of the leveling legs, the controller determines the force conditions of the legs touching the ground, and adjusts the automatic leveling algorithm in real time according to the X / Y-axis angle information. The servo drives and motors are actuators.

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