A hydraulic system leveling method
By using feedback data from level sensors, proportional speed control valves, and pressure sensors in the hydraulic system, combined with rapid calculations and actual control signal corrections, the problem of long leveling time in hydraulic systems is solved, achieving high-precision, cost-effective leveling results.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BEIJING MECHANICAL EQUIP INST
- Filing Date
- 2024-03-14
- Publication Date
- 2026-07-21
AI Technical Summary
The lack of standardized methods in existing hydraulic system leveling technology leads to unstable system operation, long leveling time, and affects the normal use of equipment.
The system uses a level sensor, a proportional speed control valve, and a pressure sensor to provide feedback data. It performs leveling through a rapid calculation method, uses the speed adjustment of the reference outrigger and adjacent outriggers to obtain the actual control signal, and corrects the hydraulic flow of the proportional speed control valve when overshoot is detected. The correction is written into the parameter list to shorten the leveling time.
It achieves a high-precision and rapid leveling process, with simple hardware, cost-effectiveness, and the ability to work continuously for a long time after leveling, thus shortening the subsequent leveling time.
Smart Images
Figure CN120650275B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of automatic leveling control technology, and in particular to an automatic leveling control method for a hydraulic system. Background Technology
[0002] With the development of industrial modernization, leveling technology is being applied in an increasingly wide range of applications, mainly for military special vehicles, engineering machinery, and other vehicles that require leveling. Leveling systems are often compared based on indicators such as leveling time, leveling accuracy, support reliability, working time, and economy.
[0003] Therefore, how to shorten the leveling time and resolve the contradictions in performance indicators, support reliability, and economy of the leveling system has become a technical problem that urgently needs to be solved and a key focus of research for those skilled in the art.
[0004] There is a lack of research on existing hydraulic system leveling techniques that address the inherent differences in hardware systems and the aging of hydraulic system parameters during later use. The lack of standardized methods leads to unstable system operation and time-consuming hydraulic system leveling, which affects the normal use of equipment. Summary of the Invention
[0005] Based on the above analysis, the present invention aims to provide an automatic leveling control method for a hydraulic system, in order to solve the problem that existing hydraulic leveling systems suffer from poor matching between control program parameters and the actual system as the system usage time increases, resulting in low leveling accuracy and long leveling time.
[0006] This invention provides a method for leveling a hydraulic system, the method comprising the following steps:
[0007] Install a level sensor between the two hydraulic outriggers of the hydraulic system; install a proportional speed control valve and a pressure sensor on the hydraulic cylinder of each outrigger;
[0008] When overshoot occurs during the leveling process of the vehicle platform in the X and / or Y directions, one of the four outriggers is taken as the reference outrigger and moves at the reference speed. Starting from the reference outrigger, adjacent outriggers are adjusted in pairs to achieve the same speed, thereby making the speed of the four outriggers the same. The control signals of each outrigger when the speed of the four outriggers is the same are obtained as the actual control signals.
[0009] When an overshoot occurs during the leveling process of the vehicle platform in a certain direction, the hydraulic system acquires the two outriggers on the lower side of that direction and simultaneously sends corresponding actual control signals to the two outriggers to level them in that direction.
[0010] Furthermore, the two adjacent outriggers are adjusted to have the same speed, and the actual control signals of the outriggers when they have the same speed are obtained:
[0011] S1. The leg that has already acquired the actual control signal among the two legs is used as the reference leg, and the other leg is the leg to be adjusted.
[0012] S2. Send the corresponding actual control signal to the reference leg, the actual control signal making the speed of the reference leg the same as the reference speed, and the control signal of the reference leg remains unchanged during the adjustment process;
[0013] S3. Apply a first control signal to the outrigger to be adjusted. Then, based on the reference speed, the distance between the reference outrigger and the outrigger to be adjusted, and the rate of change of horizontality in the direction of the reference outrigger and the outrigger to be adjusted, calculate the current speed of the outrigger to be adjusted. If the speed of the outrigger to be adjusted is the same as the speed of the reference outrigger, no more first control signal is applied to the outrigger to be adjusted, and the current first control signal is used as the actual control signal of the outrigger to be adjusted. Otherwise, the current first control signal is corrected according to the speed of the reference outrigger and the outrigger to be adjusted, and the corrected first control signal is used as the first control signal to be applied next. Return to step S3.
[0014] Furthermore, looking from the rear of the vehicle forward, the vehicle platform has a first leg positioned at the left front corner of the front, a second leg at the right front corner, a third leg at the right rear corner, and a fourth leg at the left rear corner; the first to fourth legs are arranged in a rectangle.
[0015] Furthermore, starting with the reference outrigger, adjusting adjacent outriggers in pairs to achieve the same speed means:
[0016] Assuming the reference support leg is the first support leg, first adjust the speed of the first support leg to be the same as that of the second support leg, then adjust the speed of the second support leg to be the same as that of the third support leg, and finally adjust the speed of the fourth support leg to be the same as that of the first support leg; or, first adjust the speed of the first support leg to be the same as that of the fourth support leg, then adjust the speed of the fourth support leg to be the same as that of the third support leg, and finally adjust the speed of the first support leg to be the same as that of the second support leg.
[0017] Furthermore, the level sensor includes a first level sensor and a second level sensor. The first level sensor is arranged at the midpoint between the first and second legs on the vehicle platform; the second level sensor is arranged at the midpoint between the third and fourth legs on the vehicle platform. Both level sensors include levelness signals along the X and Y directions. The positive X direction is consistent with the perpendicular direction from the fourth leg to the third leg, and the positive Y direction is consistent with the perpendicular direction from the fourth leg to the first leg.
[0018] Furthermore, based on the reference speed, the distance between the reference outrigger and the outrigger to be adjusted, and the rate of change of horizontality in the directions of the reference outrigger and the outrigger to be adjusted, the current speed of the outrigger to be adjusted is calculated, including:
[0019] When adjusting the first leg and the second leg:
[0020] The first outrigger is the reference outrigger, and the speed of the first outrigger is set to the reference speed of the outrigger hydraulic cylinder, V1 = v;
[0021] The velocity of the second leg after the (n-1)th first control signal is:
[0022] V 2(n-1) =a×sin x n-1 +v;
[0023] When adjusting the second and third legs:
[0024] The second leg serves as a reference leg.
[0025] The velocity of the third leg after the (n-1)th first control signal is:
[0026]
[0027] When adjusting the first and fourth legs:
[0028] The first outrigger is the reference outrigger, and the speed of the first outrigger is set to the reference speed of the outrigger hydraulic cylinder, V1 = v;
[0029] The velocity of the fourth leg after the (n-1)th first control signal is:
[0030] V 4(n-1) =v + b × sinz n-1 ;
[0031] Where v is the reference speed of the hydraulic cylinder of the first outrigger; a is the distance between the first and second outriggers; b is the distance between the second and third outriggers, which is also the distance between the first and fourth outriggers; x n-1 The X-direction level change rate is the result of the first level sensor after the (n-1)th first control signal is applied to the second leg; The second leg adjusts its speed at the end, using the first leg as a reference; y n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the third leg; z n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the fourth leg.
[0032] Furthermore, the actual control signal of the speed regulating valve is the sum of the starting critical threshold B and the effective control value S; the starting critical threshold B is obtained in the following way:
[0033] The pressure signal of the rodless chamber of the corresponding hydraulic cylinder is obtained by the pressure sensor of each outrigger to be adjusted; the hydraulic flow control signal of the proportional speed control valve of each outrigger to be adjusted is increased from zero in a set step size; when the pressure signal of the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve is recorded to obtain the starting critical threshold B of the speed control valve control signal.
[0034] Furthermore, the current first control signal is corrected based on the speeds of the reference outrigger and the outrigger to be adjusted, including:
[0035] When adjusting the first leg and the second leg:
[0036] When the speed of the second leg is greater than the speed of the first leg, x n-1 It is a positive value.
[0037] When x n-1 When ≥0,
[0038] When x n-1 When <0,
[0039] Therefore, the first control signal applied by the proportional speed control valve of the second leg for the nth time is:
[0040] M2 n =B2+S2 n ;
[0041] Among them, S2 n-1 M2 is the effective control value in the first control signal applied to the second outrigger for the (n-1)th time; B2 is the starting critical threshold of the proportional speed control valve control signal for the second outrigger; M2 n This is the first control signal applied to the second leg for the nth time.
[0042] Furthermore, the correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes:
[0043] When adjusting the second and third legs:
[0044] When the speed of the third leg is greater than the speed of the second leg, y n-1 It is a positive value.
[0045] When y n-1 When ≥0,
[0046] When y n-1 When <0,
[0047] This leads to the first control signal applied by the proportional speed control valve of the third leg for the nth time:
[0048] M3 n =B3+S3 n ;
[0049] Among them, S3 n-1 B3 is the effective control value in the first control signal applied to the third outrigger for the (n-1)th time; B3 is the starting critical threshold of the proportional speed control valve control signal for the third outrigger; M3 n This is the first control signal applied to the third leg for the nth time.
[0050] Furthermore, the correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes:
[0051] When adjusting the first and fourth legs:
[0052] When the speed of the fourth leg is greater than the speed of the first leg, x n-1 It is a positive value.
[0053] When z n-1 When ≥0,
[0054] When z n-1 When <0,
[0055] This leads to the first control signal applied by the proportional speed control valve of the fourth leg for the nth time:
[0056] M4 n =B4+S4 n
[0057] Among them, S4 n-1 B4 is the effective control value in the first control signal applied to the fourth outrigger for the (n-1)th time; B4 is the starting critical threshold of the proportional speed control valve control signal for the fourth outrigger; M4 n This is the first control signal applied to the fourth leg for the nth time.
[0058] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:
[0059] 1. This invention uses data from feedback from a level sensor, a proportional speed control valve, and a pressure sensor to perform leveling using a rapid calculation method. The hardware is simple, making it an economical and effective leveling method.
[0060] 2. This invention corrects the actual hydraulic flow control signal of the proportional speed control valve when overshoot is detected, so that the speeds of the four outriggers are the same. The corrected actual control signal is written into the parameter list, which can be directly called in the later leveling, thereby shortening the subsequent leveling time.
[0061] 3. This invention divides the actual control signal into a starting critical threshold and a control effective value. When the pressure signal of the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve is recorded to obtain the starting critical threshold of the control signal of each speed control valve. The control effective value is obtained by scaling the control effective value proportionally to the speed at the current moment. The algorithm is simple, the effect is obvious, and it can continue to work for a long time after leveling.
[0062] 4. Starting with the reference outrigger, adjust adjacent outriggers in pairs to achieve the same speed, thereby making all four outriggers have the same speed. This adjustment method gradually makes the speed of the four outriggers the same by adjusting in pairs. Obtain the actual control signal corresponding to the completion of the adjustment of the four outriggers. By obtaining the control signal according to the actual adjustment method, the control signal has high precision and the leveling accuracy is high.
[0063] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description
[0064] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.
[0065] Figure 1 This is a flowchart of a hydraulic system leveling method;
[0066] Figure 2 A schematic diagram showing the relationship between the hydraulic flow control signal of a proportional speed control valve and the speed of the controlled hydraulic outrigger in a hydraulic system leveling method.
[0067] Figure 3 A top view schematic diagram of the hydraulic outriggers in a hydraulic system leveling method;
[0068] Figure 4 This is a schematic diagram of the motion state of the first leg 1 and the second leg 2 in a hydraulic system leveling method.
[0069] Figure label:
[0070] 1-First leg;
[0071] 2- The second leg;
[0072] 3-The third leg;
[0073] 4 - The fourth leg;
[0074] 5. Observe from the rear of the vehicle forward. Detailed Implementation
[0075] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.
[0076] A specific embodiment of the present invention discloses a hydraulic system leveling method, the flowchart of which is shown below. Figure 1 As shown. The method includes steps S1-S3:
[0077] Step S1: Install the level sensor between the two hydraulic outriggers of the hydraulic system; install a proportional speed control valve and a pressure sensor on the hydraulic cylinder of each outrigger.
[0078] Looking forward from the rear of the vehicle, the first support leg 1 is positioned at the left front corner of the vehicle body platform, the second support leg 2 is positioned at the right front corner of the vehicle, the third support leg 3 is positioned at the right rear corner of the vehicle, and the fourth support leg 4 is positioned at the left rear corner of the vehicle; the first to fourth support legs 4 are arranged in a rectangle.
[0079] Top view of each hydraulic outrigger is shown below Figure 3 As shown.
[0080] The level sensor includes a first level sensor and a second level sensor. The first level sensor is arranged in the middle between the first leg 1 and the second leg 2 on the vehicle platform. The second level sensor is arranged in the middle between the third leg 3 and the fourth leg 4 on the vehicle platform. Both level sensors include levelness signals along the X and Y directions. The positive X direction is consistent with the perpendicular direction from the fourth leg 4 to the third leg 3, and the positive Y direction is consistent with the perpendicular direction from the fourth leg 4 to the first leg 1.
[0081] Specifically, the control computer sends control signals to the proportional valve control board, which includes a DA conversion module to convert digital control signals into analog signals. The proportional valve control board is connected to a proportional speed control valve, which can steplessly adjust the output flow rate and achieve relatively smooth regulation.
[0082] The pressure sensor is located in the oil circuit of the rodless chamber. The pressure sensor is powered by 24V±3V DC, with an output of 0-10V, a range of 0-40MPa, an accuracy of ±0.5%FS, and a temperature compensation range of -10℃ to 60℃.
[0083] The horizontal sensor measures from -10° to +10° with an error of no more than 2′, a response time of 300ms, a power supply voltage of ±12V, and an output voltage of -10V to +10V. One sensor is installed at the front and one at the rear of the vehicle to reflect the lateral and longitudinal levelness of the vehicle in real time.
[0084] Step S2: When overshoot occurs during the leveling process of the vehicle platform in the X and / or Y directions, one of the four outriggers is taken as the reference outrigger, and the reference outrigger moves at the reference speed. Starting from the reference outrigger, adjacent outriggers are adjusted to have the same speed in pairs, so that the speed of the four outriggers is the same. The control signal of each outrigger when the speed of the four outriggers is the same is obtained as the actual control signal.
[0085] Starting from the reference outrigger, adjusting adjacent outriggers pairwise to achieve the same speed means:
[0086] Assuming the reference support leg is the first support leg, first adjust the speed of the first support leg to be the same as that of the second support leg, then adjust the speed of the second support leg to be the same as that of the third support leg, and finally adjust the speed of the fourth support leg to be the same as that of the first support leg; or, first adjust the speed of the first support leg to be the same as that of the fourth support leg, then adjust the speed of the fourth support leg to be the same as that of the third support leg, and finally adjust the speed of the first support leg to be the same as that of the second support leg.
[0087] Understandably, if other support legs are used as the reference support legs, the adjustment method can also be deduced by referring to the above method. For example, if the second support leg is used as the reference support leg, first adjust the speed of the second support leg and the third support leg to be the same; then, using the third support leg as the reference support leg, adjust the speed of the fourth support leg and the third support leg to be the same, and adjust the speed of the first support leg and the second support leg to be the same.
[0088] As can be seen, by taking the reference leg as the starting point, the reference leg and its adjacent leg are first regarded as a pair of legs to be adjusted. After the adjustment is completed, the speed of the adjacent leg of the reference leg is made the same as the speed of the reference leg, and the control signal applied to the adjacent leg when the speed is the same is obtained as the actual control signal of the leg. Then, the adjacent leg and the leg next to the adjacent leg are adjusted, and finally the speed of the four legs is the same, and the actual control signal of each leg when the speed is the same is obtained.
[0089] Specifically, the two adjacent outriggers are adjusted to have the same speed, and the actual control signals of the outriggers when they have the same speed are obtained:
[0090] S21. The leg that has already acquired the actual control signal among the two legs is used as the reference leg, and the other leg is the leg to be adjusted.
[0091] S22. Send the corresponding actual control signal to the reference leg, the actual control signal making the speed of the reference leg the same as the reference speed, and the control signal of the reference leg remains unchanged during the adjustment process;
[0092] S23. Apply a first control signal to the outrigger to be adjusted, and then calculate the current speed of the outrigger to be adjusted based on the reference speed, the distance between the reference outrigger and the outrigger to be adjusted, and the rate of change of horizontality in the direction of the reference outrigger and the outrigger to be adjusted. If the speed of the outrigger to be adjusted is the same as the speed of the reference outrigger, no more first control signal is applied to the outrigger to be adjusted, and the current first control signal is used as the actual control signal of the outrigger to be adjusted; otherwise, the current first control signal is corrected according to the speed of the reference outrigger and the outrigger to be adjusted, and the corrected first control signal is used as the first control signal to be applied next, and return to step S23.
[0093] In practice, the initial value of the first control signal is set as the actual control signal of the reference outrigger. Then, the first control signal is continuously corrected according to the speed and level change rate of the outrigger to be adjusted, so that the speeds of the two outriggers are the same. The first control signal of the outrigger to be adjusted when the speeds are the same is taken as its actual control signal.
[0094] Taking the first leg 1 and the second leg 2 as examples, the motion state diagram is as follows: Figure 4 As shown.
[0095] Based on the reference speed, the distance between the reference outrigger and the outrigger to be adjusted, and the rate of change of horizontality in the directions of the reference outrigger and the outrigger to be adjusted, the current speed of the outrigger to be adjusted is calculated, including:
[0096] When adjusting the first leg 1 and the second leg 2:
[0097] The first outrigger 1 is the reference outrigger, and the speed of the first outrigger 1 is set to the reference speed of the outrigger hydraulic cylinder, V1 = v;
[0098] The velocity of the second leg 2 after the (n-1)th first control signal is:
[0099] V 2(n-1) =a×sin x n-1 +v;
[0100] When adjusting the second leg 2 and the third leg 3:
[0101] The second leg 2 is the reference leg;
[0102] The velocity of the third leg 3 after the (n-1)th first control signal is:
[0103]
[0104] When adjusting the first leg 1 and the fourth leg 4:
[0105] The first outrigger 1 is the reference outrigger, and the speed of the first outrigger 1 is set to the reference speed of the outrigger hydraulic cylinder, V1 = v;
[0106] The velocity of the fourth leg 4 after the (n-1)th first control signal is:
[0107] V 4(n-1) =v + b × sinz n-1 ;
[0108] Where, v is the reference speed of the hydraulic cylinder of the first outrigger 1; a is the distance between the first outrigger 1 and the second outrigger 2; b is the distance between the second outrigger 2 and the third outrigger 3, which is also the distance between the first outrigger 1 and the fourth outrigger 4; x n-1 The rate of change of horizontality in the X direction as reflected by the first horizontal sensor after the (n-1)th first control signal is applied to the second leg 2; The speed at the end of the adjustment of the second leg 2, with the first leg 1 as a reference; y n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the third leg 3; z n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the fourth leg 4.
[0109] The reference speed for the outrigger hydraulic cylinder is:
[0110]
[0111] Where q is the standard flow rate of the corresponding opening of the proportional speed control valve; A is the cross-sectional area of the rodless chamber of the hydraulic cylinder.
[0112] Specifically, since the front of the vehicle is the driver's cab, and the platform of the vehicle body can be used to place the boom of a crane or the lifting device of an engineering ladder, the center of gravity is often located relatively behind the vehicle body. Therefore, the Y-direction horizontality change rate reflected by the second horizontal sensor is used when calculating the Y-direction horizontality change rate.
[0113] The actual control signal of the speed control valve is the sum of the starting critical threshold B and the effective control value S; the starting critical threshold B is obtained in the following way:
[0114] The pressure signal of the rodless chamber of the corresponding hydraulic cylinder is obtained by the pressure sensor of each outrigger to be adjusted; the hydraulic flow control signal of the proportional speed control valve of each outrigger to be adjusted is increased from zero in a set step size; when the pressure signal of the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve is recorded to obtain the starting critical threshold B of the speed control valve control signal.
[0115] The current first control signal is corrected based on the speeds of the reference outrigger and the outrigger to be adjusted, including:
[0116] When adjusting the first leg 1 and the second leg 2 (assuming the first leg is the reference leg):
[0117] When the velocity of the second leg 2 is greater than the velocity of the first leg 1, x n-1 It is a positive value.
[0118] When x n-1 When ≥0,
[0119] When x n-1 When <0,
[0120] Therefore, the first control signal applied by the proportional speed control valve of the second leg 2 for the nth time is:
[0121] M2 n =B2+S2 n ;
[0122] Among them, S2 n-1 M2 is the effective control value in the first control signal applied to the second outrigger 2 for the (n-1)th time; B2 is the starting critical threshold of the proportional speed control valve control signal for the second outrigger 2; M2 n This is the first control signal applied to the second leg 2 for the nth time.
[0123] The correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes:
[0124] When adjusting the second leg 2 and the third leg 3:
[0125] When the velocity of the third leg (3) is greater than the velocity of the second leg (2), y n-1 It is a positive value.
[0126] When y n-1 When ≥0,
[0127] When y n-1 When <0,
[0128] This leads to the first control signal applied by the proportional speed control valve of the third leg 3 for the nth time:
[0129] M3 n =B3+S3 n ;
[0130] Among them, S3 n-1B3 is the effective control value in the first control signal applied to the third outrigger 3 for the (n-1)th time; B3 is the starting critical threshold of the proportional speed control valve control signal for the third outrigger 3; M3 n This is the first control signal applied to the third leg 3 for the nth time.
[0131] The correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes:
[0132] When adjusting the first leg 1 and the fourth leg 4:
[0133] When the speed of the fourth leg (4) is greater than the speed of the first leg (1), x n-1 It is a positive value.
[0134] When z n-1 When ≥0,
[0135] When z n-1 When <0,
[0136] This leads to the first control signal applied by the proportional speed control valve of the fourth leg 4 for the nth time:
[0137] M4 n =B4+S4 n
[0138] Among them, S4 n-1 B4 is the effective control value in the first control signal applied to the fourth outrigger 4 for the (n-1)th time; B4 is the starting critical threshold of the proportional speed control valve control signal for the fourth outrigger 4; M4 n This is the first control signal applied to the fourth leg 4 for the nth time.
[0139] The actual control signals of the proportional speed control valves of each outrigger after speed adjustment are written into the parameter list. The parameter list includes the actual control signals corresponding to the same speed of each outrigger. The hydraulic system is controlled according to the actual control signals in the parameter list.
[0140] Specifically, when the leveling time of the vehicle platform in the X and / or Y directions exceeds the set time threshold, the control computer will detect an overshoot in the hydraulic system's leveling process. At this point, it will activate the adjustment strategy of the hydraulic flow control signal of the proportional speed control valve. When the hydraulic flow control signal of the proportional speed control valve is below the starting critical threshold B, the controlled outrigger remains stationary. When the hydraulic flow control signal of the proportional speed control valve is above the starting critical threshold B, the speed of the controlled outrigger increases approximately proportionally with the increase of the control signal. Therefore, the hydraulic flow control signal of the proportional speed control valve is divided into the sum of the starting critical threshold B and the effective control value S. A schematic diagram of the relationship between the hydraulic flow control signal of the proportional speed control valve and the speed of the controlled hydraulic outrigger is shown below. Figure 2As shown, the actual hydraulic flow control signal of the proportional speed control valve for each outrigger is equal to the sum of the starting critical threshold and the effective value of the control signal.
[0141] When the pressure signal in the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve reaches the critical threshold for starting.
[0142] Step S3: When an overshoot occurs during the leveling process of the vehicle platform in a certain direction, the two outriggers of the hydraulic system along the lower side of that direction are acquired, and corresponding actual control signals are sent to the two outriggers to level them in that direction.
[0143] Specifically, the horizontal level of the vehicle platform in the X direction is first detected by a level sensor. If the second level sensor indicates that the right side of the vehicle platform is higher than the left side in the X direction, corresponding control signals are sent to the first support leg 1 and the fourth support leg 4, causing them to extend simultaneously. If the second level sensor indicates that the left side of the vehicle platform is higher than the right side in the X direction, the second support leg 2 and the third support leg 3 extend simultaneously. After sending the signals, the horizontal level of the vehicle platform in the X direction is acquired in real time, and it is checked whether the level is within a set threshold range. If it is within the set threshold range, the control computer considers the X direction to be level and stops sending control signals to the two lower support legs. If the level is greater than the set threshold range, control signals are sent to the two support legs until the X direction is level. Then, the platform's Y-direction levelness is detected by a level sensor. If the second level sensor indicates that the platform's positive Y-direction is higher than its negative Y-direction, corresponding control signals are sent to the third leg (3) and the fourth leg (4), causing them to extend simultaneously. If the second level sensor indicates that the platform's negative Y-direction is higher than its positive Y-direction, the first leg (1) and the second leg (2) extend simultaneously. After sending the control signals, the Y-direction levelness is acquired in real time from the level sensor. The levelness is checked to see if it is within a set threshold range. If it is within the set threshold range, the control computer considers the Y-direction level to be adjusted and stops sending control signals to those two legs. If the levelness is greater than the set threshold range, control signals are sent to the two lower legs until the Y-direction is adjusted. At this point, the horizontal level in the X direction is checked again to see if it is within the set threshold range. If the horizontal level in the X direction is greater than the set threshold range, the two outriggers along the lower side of the hydraulic system in the X direction are acquired, and corresponding actual control signals are sent to the two lower outriggers. The horizontal leveling in the X and Y directions is performed alternately with actual control signals until the horizontal level of the platform in both the X and Y directions is within the set threshold range, and the leveling is completed.
[0144] Compared with existing technologies, the hydraulic system leveling method provided in this embodiment is based on data feedback from level sensors, proportional speed control valves, and pressure sensors. It employs a rapid calculation method for leveling, has simple hardware, and is an economical and effective leveling method. When hydraulic system overshoot is detected, the actual control signal is divided into a starting critical threshold and a control effective value. When the pressure signal in the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve is recorded to obtain the starting critical threshold of each speed control valve control signal. The control effective value is obtained by proportionally scaling it with the current speed. This algorithm is simple, effective, and can continue to work for a long time after leveling. Starting with the reference outrigger, adjacent outriggers are adjusted in pairs to achieve the same speed, thereby making all four outriggers have the same speed. This adjustment method gradually makes the speeds of the four outriggers the same by adjusting them in pairs. The actual control signal corresponding to the completion of the adjustment of the four outriggers is obtained. By obtaining the control signal according to the actual adjustment method, the accuracy of the control signal and the leveling accuracy are high. By first correcting the actual hydraulic flow control signal of the proportional speed control valve to make the speed of the four outriggers the same, and writing the corrected actual control signal into the parameter list, it can be directly called in the later leveling, thereby shortening the subsequent leveling time.
[0145] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.
[0146] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for leveling a hydraulic system, characterized in that, The method includes the following steps: Install a level sensor between the two hydraulic outriggers of the hydraulic system; install a proportional speed control valve and a pressure sensor on the hydraulic cylinder of each outrigger; When overshoot occurs during the leveling process of the vehicle platform in the X and / or Y directions, one of the four outriggers will be used as the reference outrigger, and the reference outrigger will move at the reference speed. Starting with the reference outrigger, the adjacent outriggers are adjusted in pairs to achieve the same speed, thereby making the speed of all four outriggers the same. The control signals of each outrigger when the speed of all four outriggers is the same are then used as the actual control signals. The two adjacent outriggers were adjusted to have the same speed, and the actual control signals of the outriggers when they had the same speed were obtained: S1. The leg that has already acquired the actual control signal is used as the reference leg, and the other leg is the leg to be adjusted. S2. Send the corresponding actual control signal to the reference leg, the actual control signal making the speed of the reference leg the same as the reference speed, and the control signal of the reference leg remains unchanged during the adjustment process; S3. Apply a first control signal to the outrigger to be adjusted, and then calculate the current speed of the outrigger to be adjusted based on the reference speed, the distance between the reference outrigger and the outrigger to be adjusted, and the rate of change of horizontality in the direction of the reference outrigger and the outrigger to be adjusted, including: When adjusting the first and second outriggers: the first outrigger is the reference outrigger, and the speed of the first outrigger is set to the reference speed V1 of the outrigger hydraulic cylinder. The velocity of the second leg after the (n-1)th first control signal is: In 2(n-1) =a×sin + ; When adjusting the second and third legs: the second leg serves as the reference leg; The velocity of the third leg after the (n-1)th first control signal is: In 3(n-1) = +b×sins n-1 ; When adjusting the first and fourth outriggers: the first outrigger is the reference outrigger, and its speed is set to the reference speed V1 of the outrigger hydraulic cylinder. The velocity of the fourth leg after the (n-1)th first control signal is: In 4(n-1) = +b×sinz n-1 ; in, 'a' represents the reference speed for the hydraulic cylinder of the first outrigger; 'b' represents the distance between the first and second outriggers; 'b' represents the distance between the second and third outriggers, which is also the distance between the first and fourth outriggers. The X-direction level change rate is the result of the first level sensor after the (n-1)th first control signal is applied to the second leg; The second leg adjusts its speed at the end, using the first leg as a reference; y n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the third leg; z n-1 The rate of change of horizontality in the Y direction as reflected by the second horizontal sensor after the (n-1)th first control signal is applied to the fourth leg; If the speed of the outrigger to be adjusted is the same as the speed of the reference outrigger, the first control signal is no longer applied to the outrigger to be adjusted, and the current first control signal is used as the actual control signal of the outrigger to be adjusted; otherwise, the current first control signal is corrected according to the speed of the reference outrigger and the outrigger to be adjusted, and the corrected first control signal is used as the first control signal to be applied next, and the process returns to step S3. The step of correcting the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted includes: When adjusting the first leg and the second leg: When the speed of the second leg is set to be greater than the speed of the first leg It is a positive value. when When ≥0, ; when When <0, ; Therefore, the first control signal applied by the proportional speed control valve of the second leg for the nth time is: ； in, The effective control value in the first control signal applied to the second leg for the (n-1)th time; The critical threshold for starting the proportional speed control valve control signal of the second leg; This is the first control signal applied to the second leg for the nth time. Viewed from the rear of the vehicle, the first leg is positioned at the left front corner of the front of the vehicle, the second leg at the right front corner of the front of the vehicle, the third leg at the right rear corner of the rear of the vehicle, and the fourth leg at the left rear corner of the rear of the vehicle; the first to fourth legs are arranged in a rectangle. When an overshoot occurs during the leveling process of the vehicle platform in a certain direction, the hydraulic system acquires the two outriggers on the lower side of that direction and simultaneously sends corresponding actual control signals to the two outriggers to level them in that direction.
2. The leveling method according to claim 1, characterized in that, Starting from the reference outrigger, adjusting adjacent outriggers pairwise to achieve the same speed means: Assuming the reference support leg is the first support leg, first adjust the speed of the first support leg to be the same as that of the second support leg, then adjust the speed of the second support leg to be the same as that of the third support leg, and finally adjust the speed of the fourth support leg to be the same as that of the first support leg; or, first adjust the speed of the first support leg to be the same as that of the fourth support leg, then adjust the speed of the fourth support leg to be the same as that of the third support leg, and finally adjust the speed of the first support leg to be the same as that of the second support leg.
3. The leveling method according to claim 2, characterized in that, The level sensor includes a first level sensor and a second level sensor. The first level sensor is arranged at the midpoint between the first and second legs on the vehicle platform. The second level sensor is arranged at the midpoint between the third and fourth legs on the vehicle platform. Both level sensors include levelness signals along the X and Y directions. The positive X direction is consistent with the perpendicular direction from the fourth leg to the third leg, and the positive Y direction is consistent with the perpendicular direction from the fourth leg to the first leg.
4. The leveling method according to claim 3, characterized in that, The actual control signal of the speed control valve is the sum of the starting critical threshold B and the effective control value S; the starting critical threshold B is obtained in the following way: The pressure signal of the rodless chamber of the corresponding hydraulic cylinder is obtained by the pressure sensor of each outrigger to be adjusted; the hydraulic flow control signal of the proportional speed control valve of each outrigger to be adjusted is increased from zero in a set step size; when the pressure signal of the rodless chamber begins to fluctuate, the hydraulic flow control signal of the proportional speed control valve is recorded to obtain the starting critical threshold B of the speed control valve control signal.
5. The leveling method according to claim 1, characterized in that, The correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes: When adjusting the second and third legs: When the speed of the third leg is set to be greater than the speed of the second leg It is a positive value. when When ≥0, ; when When <0, ; This leads to the first control signal applied by the proportional speed control valve of the third leg for the nth time: ； in, The effective control value in the first control signal applied to the third leg for the (n-1)th time; The critical threshold for starting the proportional speed control valve control signal of the third leg; This is the first control signal applied to the third leg for the nth time.
6. The leveling method according to claim 1, characterized in that, The correction of the current first control signal based on the speeds of the reference outrigger and the outrigger to be adjusted also includes: When adjusting the first and fourth legs: When the speed of the fourth leg is greater than the speed of the first leg It is a positive value. when When ≥0, ; when When <0, ; This leads to the first control signal applied by the proportional speed control valve of the fourth leg for the nth time: in, The effective control value in the first control signal applied to the fourth leg for the (n-1)th time; The critical threshold for starting the proportional speed control valve control signal of the fourth leg; This is the first control signal applied to the fourth leg for the nth time.