Control methods and control systems for lifting platforms

Abstract

This disclosure provides a control method and control system for a lifting platform, belonging to the field of marine platform technology. The control method includes: acquiring the displacement of a first lifting cylinder among a plurality of lifting cylinders; calculating a displacement difference between the first lifting cylinder and the first lifting cylinder based on the displacement of the first lifting cylinder, wherein the displacement difference is the difference between the displacement of a main cylinder and the displacement of the first lifting cylinder, and the main cylinder is one of the plurality of lifting cylinders; and controlling the extension and retraction speed of the first lifting cylinder based on the displacement difference. This disclosure can reduce the displacement error between lifting cylinders and ensure real-time synchronization of the lifting cylinders.

Description

Technical Field

[0001] This disclosure belongs to the field of marine platform technology, and specifically relates to a control method and control system for a lifting platform. Background Technology

[0002] A lifting platform is a structure that provides production and living facilities for activities such as drilling, oil production, cargo transportation, observation, navigation, and construction at sea. Common types of lifting platforms include multi-cylinder lifting platforms (also known as hydraulic pin-type lifting platforms) and rack and pinion lifting platforms. Multi-cylinder lifting platforms are often used in ports for connecting cruise ships and transporting personnel, luggage, and cargo. Multi-cylinder lifting platforms are typically driven by multiple lifting cylinders; that is, the synchronous extension and retraction of multiple lifting cylinders achieves the lifting and lowering of the platform.

[0003] In related technologies, when a multi-cylinder lifting platform is lifting, the displacement of each lifting cylinder is controlled to be at its maximum or minimum so that the lifting platform can lift the same height each time.

[0004] However, during the extension and retraction of the lifting cylinders, the actual lifting height may vary depending on the maximum or minimum displacement of each lifting cylinder. This makes it difficult to ensure that the displacement difference between the lifting cylinders remains within 10mm (leading to asynchronous lifting cylinders). Consequently, the lifting platform may tilt during the extension and retraction of the lifting cylinders, potentially pulling on the piston rod of the lifting cylinder and causing it to deform. Summary of the Invention

[0005] This disclosure provides a control method for a lifting platform, which can reduce displacement errors between lifting cylinders and ensure real-time synchronization of the lifting cylinders. The technical solution is as follows:

[0006] This disclosure provides a control method for a lifting platform, wherein the lifting of the platform is driven by a plurality of lifting cylinders. The control method includes: acquiring the displacement of a first lifting cylinder among the plurality of lifting cylinders; calculating a displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder, wherein the displacement difference is the difference between the displacement of a main cylinder and the displacement of the first lifting cylinder, and the main cylinder is one of the plurality of lifting cylinders; and controlling the extension and retraction speed of the first lifting cylinder based on the displacement difference.

[0007] In another implementation of this disclosure, the oil inlet circuit of the first lifting cylinder is provided with a first proportional valve, the first proportional valve is electrically connected to a controller, the controller has a first input channel, the first input channel is used to receive a first channel input value, the first channel input value is used to control the opening size of the first proportional valve; the step of controlling the extension and retraction speed of the first lifting cylinder according to the displacement difference includes: when the controller receives an instruction that the displacement difference is not equal to zero, adjusting the first channel input value to control the extension and retraction speed of the first lifting cylinder and to control the extension and retraction speed of the first lifting cylinder to be not zero.

[0008] In another implementation of this disclosure, when the controller receives an instruction that the displacement difference is not equal to zero, it adjusts the first channel input value to control the extension and retraction speed of the first lifting cylinder and to ensure that the extension and retraction speed of the first lifting cylinder is not zero. This includes: the controller adjusting the first channel input value according to the displacement difference and an adjustment limit, and during the adjustment process, the adjusted value of the first channel input value is not greater than the adjustment limit; the adjustment limit is obtained based on the adjustment base of the first proportional valve and the input range of the first input channel, wherein the adjustment base is the first channel input value corresponding to the opening size of the first proportional valve when the lifting platform moves up and down at the target speed.

[0009] In another implementation of this disclosure, the controller is provided with adjustment parameters, including the minimum speed adjustment value b of the lifting cylinder and the minimum time c corresponding to the adjustment range limit of the proportional valve opening size; the controller adjusts the first channel input value according to the displacement difference and the adjustment limit, including: if the displacement difference s is greater than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than c, then the first channel input value is controlled to increase by the adjustment limit; or, if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is less than -c, then the first channel input value is controlled to decrease by the adjustment limit; or, if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than -c, then the first channel input value is controlled to decrease linearly with time and the first channel input value is controlled not to exceed the adjustment limit; or, if the displacement difference s is greater than zero and less than the ratio of the displacement difference to the minimum speed adjustment value greater than c, then the first channel input value is controlled to increase linearly with time and the first channel input value is controlled not to exceed the adjustment limit.

[0010] In another implementation of this disclosure, the control method further includes: when the controller receives an instruction to open a proportional valve, adjusting the channel input value to control the opening size of each proportional valve to increase or decrease at a uniform rate to the target opening indicated by the opening instruction.

[0011] In another implementation of this disclosure, the plurality of lifting cylinders are divided into multiple groups, and each group of lifting cylinders includes two lifting cylinders connected to both sides of the lifting platform in the width direction. The control method further includes: if the second lifting cylinder in the plurality of lifting cylinders fails, controlling all lifting cylinders in the same group to stop operating.

[0012] In another implementation of this disclosure, a control system for a lifting platform is also provided. The lifting of the lifting platform is driven by multiple lifting cylinders. The control system includes: an acquisition unit for acquiring the displacement of a first lifting cylinder among the multiple lifting cylinders; a calculation unit for calculating a displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder, wherein the displacement difference is the difference between the displacement of a main cylinder and the displacement of the first lifting cylinder, and the main cylinder is one of the multiple lifting cylinders; and a control unit for controlling the extension and retraction speed of the first lifting cylinder based on the displacement difference.

[0013] In another implementation of this disclosure, the oil inlet circuit of the first lifting cylinder is provided with a first proportional valve, the first proportional valve is electrically connected to a controller, the controller has a first input channel, the first input channel is used to receive a first channel input value, the first channel input value is used to control the opening size of the first proportional valve; the control unit is further used to adjust the first channel input value when the controller receives an instruction that the displacement difference is not equal to zero, so as to control the extension and retraction speed of the first lifting cylinder and control the extension and retraction speed of the first lifting cylinder to be not zero.

[0014] In another implementation of this disclosure, a computer device is also provided, the computer device including a processor and a memory configured to store processor-executable instructions; the processor is configured to execute the lifting platform control method described above.

[0015] In another implementation of this disclosure, a computer storage medium is also provided, on which computer instructions are stored, which, when executed by a processor, implement the control method of the lifting platform described above.

[0016] The beneficial effects of the technical solutions provided in this disclosure are:

[0017] When the lifting platform is controlled by the control method provided in this embodiment, the control method can obtain the displacement of the lifting cylinder in real time, and obtain the displacement difference of each first lifting cylinder according to the displacement of the first lifting cylinder among multiple lifting cylinders. Then, the extension and retraction speed of the first lifting cylinder is adjusted according to the displacement difference, so that the displacement difference of the first lifting cylinder becomes 0, that is, the displacement of all lifting cylinders is the same, thereby enabling the lifting platform to always be horizontal and the lifting cylinders to keep synchronized.

[0018] In other words, the above control method can automatically adjust in real time according to the displacement difference of the lifting cylinders, so that the displacement of each lifting cylinder remains the same, ensuring that the lifting cylinders do not become out of sync, and can be adjusted to synchronize them at any time. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of the lifting platform provided in the embodiments of this disclosure;

[0021] Figure 2 yes Figure 1 A cross-sectional view along the AA direction;

[0022] Figure 3 yes Figure 1 Top view;

[0023] Figure 4 This is a flowchart of a control method for a lifting platform provided in an embodiment of this disclosure;

[0024] Figure 5 This is a flowchart of another control method for a lifting platform provided in an embodiment of this disclosure;

[0025] Figure 6 This is a logic diagram of the control method provided in this embodiment during adjustment;

[0026] Figure 7 yes Figure 6 The adjustment function diagram when the controller is adjusted;

[0027] Figure 8 This is a schematic diagram of a control system for a lifting platform provided in an embodiment of this disclosure;

[0028] Figure 9This is a schematic diagram of a computer provided in an embodiment of this disclosure.

[0029] The symbols in the diagram represent the following meanings:

[0030] 101. Fixed beam; 102. Moving beam; 103. Lifting cylinder. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0032] like Figure 1-3 As shown, lifting platforms are mainly used for connecting cruise ships at ports, and for transporting personnel, luggage, and cargo. For example, lifting platforms are used upstream of the Three Gorges Dam. Due to changes in water level upstream of the dam, the "link" connecting cruise ships to the other side needs to be adjusted to a suitable position according to the water level. The entire link consists of five lifting platforms, each a multi-cylinder lifting platform. Each platform adjusts its vertical position through the synchronous extension and retraction of multiple lifting cylinders. In other words, the multi-cylinder lifting platform provides a link for pedestrian movement between cruise ships and passenger terminals.

[0033] The lifting platform includes the platform body, four fixed beams 101, four moving beams 102, and eight lifting cylinders 103.

[0034] All four fixed beams 101 and four movable beams 102 are located at the bottom of the platform body. Two of the four movable beams 102 are located at one end of the platform body along its length, while the other two are located at the other end. The length of each movable beam 102 is the same as the width of the platform body. Each movable beam 102 is connected to the platform body to support its lifting and lowering.

[0035] Four fixed beams 101 and four movable beams 102 are arranged in a one-to-one correspondence, and the projection of each fixed beam 101 onto the platform body coincides with the projection of the corresponding movable beam 101 onto the platform body along a direction perpendicular to the platform body. Two of the eight lifting cylinders 103 are connected between corresponding fixed beams 101 and movable beams 102, respectively. The extension and retraction direction of each lifting cylinder 103 is perpendicular to the platform body.

[0036] Since the lifting platform serves as a link for pedestrian movement between cruise ships and passenger stations, a certain degree of redundancy is required for safety reasons. Even if a single lifting cylinder 103 in the multi-cylinder lifting platform fails, the platform can still rise and fall normally, maintaining the link. Therefore, two moving beams 102 are simultaneously installed at one end of the platform body along its length. This allows the platform body to be raised and lowered normally even if one moving beam 102 fails (e.g., the lifting cylinder connected to the moving beam 102 cannot operate). In other words, the multi-cylinder lifting platform provided in this embodiment can achieve the raising and lowering of the platform body using the other three moving beams 102 when a single lifting cylinder 103 fails or a fault occurs at a certain point on the same moving beam 102.

[0037] In related technologies, the above-mentioned lifting platform raises and lowers by controlling the synchronous extension and retraction of eight lifting cylinders. This means that by controlling the piston rods of the eight lifting cylinders to extend and retract at the same speed, the displacement of each lifting cylinder can be synchronously at its maximum or minimum, ensuring that the platform body rises and falls to the same height each time and remains horizontal during the process. However, because the actual lifting height varies depending on the maximum or minimum displacement of each lifting cylinder, it is difficult to guarantee that the displacement difference between the lifting cylinders is always within 10mm. For example, ... Figure 2 As shown, Figure 2 When the displacement of the left-hand lifting cylinder changes from zero to its maximum, there may be a discrepancy of more than 10mm between the extended piston rod length and the extended piston rod length of the right-hand lifting cylinder. In this case, the platform will inevitably tilt, causing personnel on the platform to sway, or the lifting platform may pull on the piston rod of the lifting cylinder, causing deformation. Therefore, the platform needs to be leveled.

[0038] This disclosure provides a control method for a lifting platform, used to control the aforementioned lifting platform, such as... Figure 4 As shown, the control methods include:

[0039] S401: Obtain the displacement of the first lifting cylinder among multiple lifting cylinders.

[0040] S402: Calculate the displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder. The displacement difference is the difference between the displacement of the main cylinder and the displacement of the first lifting cylinder. The main cylinder is one of multiple lifting cylinders.

[0041] The first lifting cylinder is any lifting cylinder other than the main cylinder among multiple lifting cylinders.

[0042] S403: Control the extension and retraction speed of the first lifting cylinder based on the displacement difference.

[0043] When the lifting platform is controlled by the control method provided in this embodiment, the control method can obtain the displacement of the lifting cylinder in real time, and obtain the displacement difference of each first lifting cylinder according to the displacement of the first lifting cylinder among multiple lifting cylinders. Then, the extension and retraction speed of the first lifting cylinder is adjusted according to the displacement difference, so that the displacement difference of the first lifting cylinder becomes 0, that is, the displacement of all lifting cylinders is the same, thereby enabling the lifting platform to always be horizontal and the lifting cylinders to keep synchronized.

[0044] The above control method can automatically adjust in real time according to the displacement difference of the lifting cylinders, so that the displacement of each lifting cylinder remains the same, ensuring that the lifting cylinders do not become out of sync, and can be adjusted to synchronize them at any time. In other words, the control method provided in this embodiment can synchronously control multiple lifting cylinders 103, ensuring that the entire platform body remains horizontal during the lifting process, and that the moving beam will not pull the piston rod of the lifting cylinder 103 and cause it to deform during lifting.

[0045] This disclosure also provides another control method for a lifting platform, used to control the aforementioned lifting platform. For example... Figure 5 As shown, the control method includes:

[0046] S501: Obtain the displacement of the first lifting cylinder among multiple lifting cylinders.

[0047] Multiple lifting cylinders are used to drive the lifting platform to move up and down.

[0048] The displacement of the lifting cylinder is the extension stroke of the piston rod of the lifting cylinder.

[0049] In this embodiment of the disclosure, by connecting a stroke sensor to each lifting cylinder, the displacement of each lifting cylinder can be detected accordingly.

[0050] S502: Calculate the displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder.

[0051] The displacement difference is the difference between the displacement of the main hydraulic cylinder and the displacement of the first lifting hydraulic cylinder. The main hydraulic cylinder is one of multiple lifting hydraulic cylinders.

[0052] During the lifting process, the eight lifting cylinders at the bottom of the lifting platform may not be synchronized, which can easily lead to uneven force distribution and tilting of the platform. Therefore, the eight lifting cylinders must be synchronized during the lifting process. The displacement difference between each of the eight lifting cylinders and the main cylinder should be within 10mm.

[0053] To achieve synchronous control of the eight lifting cylinders, one of them is designated as the master cylinder and also the reference cylinder, while the others are follow-up lifting cylinders, also referred to as the first lifting cylinders. The displacement of the master cylinder is used as the reference displacement. The difference between the reference displacement and the displacements of the other first lifting cylinders is calculated, thus yielding the displacement difference of the first lifting cylinders.

[0054] For example, to facilitate recording, the displacement of the first lifting cylinder at the rear of the lifting platform is used as the reference displacement.

[0055] S503: When the controller receives an instruction that the displacement difference is not equal to zero, it adjusts the input value of the first channel to control the extension and retraction speed of the first lifting cylinder and ensures that the extension and retraction speed of the first lifting cylinder is not zero.

[0056] In this embodiment, a proportional valve is connected to the oil inlet line of each lifting cylinder, and the proportional valves are arranged in a one-to-one correspondence with the lifting cylinders. The proportional valve in the oil inlet line of the first lifting cylinder is a first proportional valve.

[0057] In this way, the extension and retraction speed of the first lifting cylinder can be adjusted by controlling the opening size of the first proportional valve, thereby changing the displacement difference of the first lifting cylinder.

[0058] Obviously, if the displacement difference of the first lifting cylinder is greater than zero, then when the platform body rises, the opening of the first proportional valve can be increased to increase the speed of the first lifting cylinder, or when the platform body descends, the opening of the first proportional valve can be decreased to reduce the speed of the first lifting cylinder.

[0059] If the displacement difference is less than zero, when the platform body rises, the opening of the first proportional valve is reduced to decrease the speed of the first lifting cylinder; or when the platform body descends, the opening of the first proportional valve is increased to increase the speed of the first lifting cylinder.

[0060] Since proportional valves are generally controlled by electromagnetic signals, for ease of control, each proportional valve can be electrically connected to the same controller so that the opening of each proportional valve can be controlled by the controller.

[0061] The controller has multiple input channels, each corresponding to a proportional valve. Each input channel is used to input a different input value. The input value of each input channel controls the opening size of the proportional valve corresponding to that input channel.

[0062] In other words, there is a one-to-one mapping between the channel input value in the first input channel and the input current of the first proportional valve. Since the input current of the first proportional valve corresponds one-to-one with the valve opening size, this mapping reflects the one-to-one correspondence between the valve opening size and the corresponding channel input value. The input current has a range, and the channel input value in each input channel has an input range that maps to the input current range of the proportional valve corresponding to that input channel. The input channel corresponding to the first proportional valve is the first input channel, and different channel input values ​​within the first input channel are the first channel input values.

[0063] In this way, the opening size of the first proportional valve can be changed by altering the channel input value in the first input channel corresponding to the first proportional valve.

[0064] In other words, when the controller receives a signal that the displacement difference is not equal to zero, the controller can adjust the input value of the first channel so that the opening size of the first proportional valve is not zero, thereby controlling the extension and retraction speed of the first lifting cylinder, and ultimately making the displacement difference become 0.

[0065] Optionally, step S503 can be implemented in the following manner:

[0066] The controller adjusts the first channel input value based on the displacement difference and the adjustment limit, and during the adjustment process, the adjusted value of the first channel input value does not exceed the adjustment limit. The adjustment limit is obtained based on the adjustment base of the first proportional valve and the input range of the first input channel. The adjustment base is the first channel input value corresponding to the opening size of the first proportional valve when the lifting platform rises and falls at the target speed.

[0067] The input current of a proportional valve is directly related to its opening size and direction. For example, in this embodiment, the input current of the proportional valve corresponds to a range of 4-20mA. When the input current is 12mA, the proportional valve is in the neutral position. When the input current is greater than 12mA, the opening is in the right position, and as the input current gradually increases, the opening gradually increases until it reaches its maximum (100%) when the input current reaches 20mA. When the input current is less than 12mA but greater than 4mA, the opening is in the left position. When the input current is in the 4-12mA range, as the input current gradually decreases, the opening gradually decreases until it reaches the neutral position when the input current reaches 12mA.

[0068] When a proportional valve is controlled by a controller, different input values ​​in each input channel of the controller can control the input current of the corresponding proportional valve, thereby controlling the opening size of the proportional valve. In other words, by inputting different input values ​​into any input channel of the controller, the opening size of the proportional valve corresponding to that input channel can be controlled.

[0069] In other words, the input value of one channel in an input channel corresponds to an input current of the corresponding proportional valve, which in turn corresponds to the opening size of the proportional valve. Thus, the input range of the channel input value for each input channel can be determined based on the range of the proportional valve's input current.

[0070] In this embodiment, all proportional valves have the same specifications, and the input current range of each proportional valve is 4-20mA. Correspondingly, the input channel value range of each input channel in the controller is 0-10000. That is, the input channel value range of 0-10000 corresponds to the input current of the corresponding proportional valve being 4-20mA. Thus, when the proportional valve is in the neutral position, the input current of the proportional valve is 12mA, and the corresponding channel input value in the controller is 5000. In other words, when the input current range of the proportional valve is 4-20mA, the input range of the channel input value in each input channel of the controller is 5000±5000.

[0071] In this embodiment, when the opening size of the proportional valve is 35%, the lifting platform rises and falls normally at the target speed. Therefore, the adjustment base of the proportional valve = 5000 ± 5000 * 35%.

[0072] In other words, when the controller's input channel value is 5000 + 1750, the proportional valve opening meets the requirements, and the lifting cylinder can raise the lifting platform normally. When the controller's input channel value is 5000 - 1750, the proportional valve opening meets the requirements, and the lifting cylinder can lower the lifting platform normally.

[0073] When the lifting platform is rising normally, the corresponding channel input value of the controller is 5000 + 1750 = 6750. Therefore, if the displacement difference is not equal to 0, when adjusting the first lifting cylinder, the opening of the first proportional valve must not be 0, that is, the first proportional valve cannot return to the neutral position. Therefore, the first channel input value must always be greater than 5000. Consequently, the adjustment limit of the first channel input value (that is, the maximum adjustment limit) needs to be less than 1750.

[0074] Because the controller's input value for the channel is 5000 - 1750 = 3250 during normal descent of the lifting platform, if the displacement difference is not zero, the first proportional valve cannot return to its neutral position when adjusting the first lifting cylinder. Therefore, the first channel input value must always be less than 5000. Consequently, the adjustment limit of the first channel input value (i.e., the maximum adjustment limit) must also be less than 1750.

[0075] In some examples, the adjustment limit can be set to 1500.

[0076] The above step, "Adjust the first channel input value based on the displacement difference and adjustment limit," may include:

[0077] The controller has adjustment parameters. These parameters include the minimum speed adjustment value b for the lifting cylinder and the minimum time c corresponding to the adjustment range limit of the proportional valve opening size.

[0078] (1) If the displacement difference s is greater than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than c, the controller controls the first channel input value to increase the adjustment limit.

[0079] (2) If the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is less than -c, the controller controls the first channel input value to decrease the adjustment limit.

[0080] (3) If the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than -c, the controller controls the first channel input value to decrease linearly with time, and the decrease in the first channel input value controlled by the controller is not greater than the adjustment limit.

[0081] (4) If the displacement difference s is greater than zero and less than the ratio of the displacement difference to the minimum speed adjustment value is greater than c, the controller controls the first channel input value to increase linearly with time, and the increase in the controller controls the first channel input value not to exceed the adjustment limit.

[0082] Figure 6 This is a judgment logic diagram of the control method provided in this embodiment during adjustment, combined with... Figure 6 By setting adjustment parameters, when the displacement difference is large, the first channel input value in the controller can be automatically adjusted according to the adjustment limit, causing the opening of the proportional valve to increase rapidly. When the displacement difference is small, the first channel input value can be automatically and gradually adjusted to the opening of the first proportional valve at a linearly increasing or decreasing rate.

[0083] Figure 7 yes Figure 6 The adjustment function diagram when the controller is adjusted, combined with Figure 7 For visualization purposes, the adjustment value (i.e., the change) of the channel input value during adjustment can also be combined with... Figure 7 get. Figure 7 In this example, 'a' is an adjustment coefficient; the larger 'a' is, the faster the adjustment. In this example, a = 100, b = 1.5 mm / s, and c = 15.0 s.

[0084] When the lifting mechanism is rising, if the displacement difference is not 0, the first channel input value in the controller is: 5000 + 5000 & 35% + adjustment value.

[0085] If the displacement difference is not 0 during the lifting and lowering process, the first channel input value in the controller is: 5000-5000&35%-adjustment value.

[0086] The adjustment value can be obtained by following the steps above.

[0087] S504: When the controller receives a command to open a proportional valve, it adjusts the channel input value to control the opening size of each proportional valve to increase or decrease at a uniform rate until it reaches the target opening indicated by the opening command.

[0088] In this embodiment of the disclosure, when the lifting platform needs to be raised or lowered, after receiving the lifting button operation, the controller first needs to load the corresponding pump station in the lifting cylinder. After a delay of a few seconds (generally 6 seconds), the proportional valve is loaded.

[0089] Because if the proportional valve moves directly from the neutral position to the designated opening position, the hydraulic system will experience a significant shock, causing a noticeable jerking sensation for personnel on the lifting platform. To reduce hydraulic shock, a ramp function (where the opening of the proportional valve is proportional to time) is used to control the proportional valve during both startup and shutdown. This ensures that the valve opening accelerates or decelerates evenly from the neutral position to the designated opening. Once the designated opening is reached, the valve is readjusted according to steps S501-502.

[0090] S505: If the second lifting cylinder in a group of multiple lifting cylinders malfunctions, all lifting cylinders in the same group as the second lifting cylinder will be prevented from operating.

[0091] In this embodiment, the multiple lifting cylinders are divided into multiple groups, and each group of lifting cylinders includes two lifting cylinders connected to both sides of the lifting platform in the width direction. The same group of lifting cylinders is connected to the same moving beam.

[0092] When a moving beam of the lifting platform malfunctions, such as a faulty lifting cylinder or a faulty stroke sensor connected to that moving beam, and the lifting platform needs to operate promptly, the moving beam with the fault can be shielded, that is, the lifting cylinder connected to the faulty moving beam can be shielded.

[0093] It should be noted that only one moving beam can be shielded during shielding. In this case, the controller will not control the lifting cylinder.

[0094] The terms "first lifting cylinder" and "second lifting cylinder" are used only to distinguish lifting cylinders in different situations during writing and do not restrict the order. In the same embodiment, the first lifting cylinder and the second lifting cylinder may be the same cylinder or they may be different.

[0095] This disclosure also provides a control system for a lifting platform, such as... Figure 8As shown, the control system is used to execute the above control method. The control system includes an acquisition unit 801, a calculation unit 802, and a control unit 803.

[0096] The acquisition unit 801 is used to acquire the displacement of the first lifting cylinder among multiple lifting cylinders.

[0097] The calculation unit 802 is used to calculate the displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder. The displacement difference is the difference between the displacement of the main cylinder and the displacement of the first lifting cylinder. The main cylinder is one of a plurality of lifting cylinders.

[0098] The control unit 803 is used to control the extension and retraction speed of the first lifting cylinder according to the displacement difference. The above control system has the same beneficial effects as the aforementioned control method, and will not be described in detail here.

[0099] Optionally, the control unit 803 is further configured to adjust the first channel input value when the controller receives an instruction that the displacement difference is not equal to zero, so as to control the extension and retraction speed of the first lifting cylinder and control the extension and retraction speed of the first lifting cylinder to be not zero.

[0100] Optionally, the control unit 803 is also used to adjust the first channel input value according to the displacement difference and the adjustment limit, so that the adjustment value of the first channel input value is not greater than the adjustment limit during the adjustment process.

[0101] Optionally, the control unit 803 is further configured to: if the displacement difference s is greater than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than c, control the first channel input value to increase by an adjustment limit; or if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is less than -c, control the first channel input value to decrease by an adjustment limit; or if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than -c, control the first channel input value to decrease linearly over time and control the first channel input value not to exceed the adjustment limit; or if the displacement difference s is greater than zero and less than the ratio of the displacement difference to the minimum speed adjustment value greater than c, control the first channel input value to increase linearly over time and control the first channel input value not to exceed the adjustment limit.

[0102] Optionally, the control unit 803 is also used to adjust the channel input value when the controller receives a command to open the proportional valve, so as to control the opening size of each proportional valve to increase or decrease at a constant speed to the target opening indicated by the opening command.

[0103] Optionally, the control unit 803 is also used to control all lifting cylinders in the same group as the second lifting cylinder to stop operating if the second lifting cylinder among the multiple lifting cylinders fails.

[0104] It should be noted that the control method for the lifting platform provided in the above embodiments is only an example of the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the control system and the control method of the lifting platform provided in the above embodiments belong to the same concept, and the specific implementation process can be found in the method embodiments, which will not be described in detail here.

[0105] Figure 9 This is a schematic diagram of the structure of a computer device provided in an embodiment of the present disclosure, combined with... Figure 9 The computer device 900 may include one or more of the following components: processor 901, memory 902, communication interface 903, and bus 904.

[0106] The processor 901 includes one or more processing cores. The processor 901 executes various functional applications and information processing by running software programs and modules. The memory 902 and the communication interface 903 are connected to the processor 901 via a bus 904. The memory 902 can be used to store at least one instruction, which the processor 901 uses to execute to implement the various steps in the above method.

[0107] Furthermore, the memory 902 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, including but not limited to: magnetic disks or optical disks, electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), read-only memory (ROM), magnetic storage, flash memory, and programmable read-only memory (PROM).

[0108] This disclosure also provides a computer-readable storage medium storing computer instructions. When the computer instructions stored in the computer-readable storage medium are executed by an electronic device, the electronic device performs the lifting platform control method provided in the above-described method embodiments.

[0109] This disclosure also provides a computer program product, which includes one or more computer program instructions. When the computer program instructions are loaded and run by a computer, the computer executes the control method for the lifting platform provided in the above-described method embodiments.

[0110] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A control method for a lifting platform, characterized in that, The lifting platform serves as a link for pedestrian movement between the cruise ship and the passenger station. The lifting of the platform is driven by multiple lifting cylinders, and the control method includes: The displacement of the first lifting cylinder among the plurality of lifting cylinders is obtained. The oil inlet circuit of the first lifting cylinder is provided with a first proportional valve. The first proportional valve is electrically connected to the controller. The controller has a first input channel and is provided with adjustment parameters. The first input channel is used to receive a first channel input value. The first channel input value is used to control the opening size of the first proportional valve. The adjustment parameters include the minimum speed adjustment value b of the lifting cylinder and the minimum time c corresponding to the adjustment range limit of the opening size of the first proportional valve. Based on the displacement of the first lifting cylinder, the displacement difference of the first lifting cylinder is calculated. The displacement difference is the difference between the displacement of the main cylinder and the displacement of the first lifting cylinder. The main cylinder is one of the plurality of lifting cylinders. Based on the displacement difference, when the controller receives an instruction that the displacement difference is not equal to zero, it controls the extension and retraction speed of the first lifting cylinder by adjusting the input value of the first channel and controls the extension and retraction speed of the first lifting cylinder to be not zero. The controller adjusts the first channel input value based on the displacement difference and the adjustment limit. During the adjustment process, the adjusted value of the first channel input value is not greater than the adjustment limit. The adjustment limit is obtained based on the adjustment base of the first proportional valve and the input range of the first input channel. The adjustment base is the first channel input value corresponding to the opening size of the first proportional valve when the lifting platform rises and falls at the target speed. The adjustment method for the first channel input value is as follows: If the displacement difference s is greater than zero, and the ratio of the displacement difference to the minimum speed adjustment value is greater than the minimum time c, the controller controls the first channel input value to increase by the adjustment limit; or, if the displacement difference s is less than zero, and the ratio of the displacement difference to the minimum speed adjustment value is less than the negative of the minimum time c - c, the controller controls the first channel input value to decrease by the adjustment limit; or, if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than the negative of the minimum time c - c, the controller controls the first channel input value to decrease linearly with time, and controls the first channel input value not to exceed the adjustment limit; or, if the displacement difference s is greater than zero and less than the ratio of the displacement difference to the minimum speed adjustment value, and greater than the minimum time c, the controller controls the first channel input value to increase linearly with time, and controls the first channel input value not to exceed the adjustment limit.

2. The control method according to claim 1, characterized in that, The control method further includes: When the controller receives a command to open a proportional valve, it adjusts the channel input value to control the opening size of each proportional valve to increase or decrease at a uniform rate to the target opening indicated by the opening command.

3. The control method according to claim 1 or 2, characterized in that, The plurality of lifting cylinders are divided into multiple groups, and each group of lifting cylinders includes two lifting cylinders connected to both sides of the lifting platform in the width direction. The control method further includes: If the second lifting cylinder among the plurality of lifting cylinders malfunctions, all lifting cylinders in the same group as the second lifting cylinder will be prevented from operating.

4. A control system for a lifting platform, characterized in that, The lifting platform serves as a link for pedestrian movement between the cruise ship and the passenger station. The lifting of the platform is driven by multiple lifting cylinders, and the control system includes: The acquisition unit is used to acquire the displacement of the first lifting cylinder among the plurality of lifting cylinders. The oil inlet circuit of the first lifting cylinder is provided with a first proportional valve. The first proportional valve is electrically connected to the controller. The controller has a first input channel and is provided with adjustment parameters. The first input channel is used to receive a first channel input value. The first channel input value is used to control the opening size of the first proportional valve. The adjustment parameters include the minimum speed adjustment value b of the lifting cylinder and the minimum time c corresponding to the adjustment range limit of the opening size of the first proportional valve. The calculation unit is used to calculate the displacement difference of the first lifting cylinder based on the displacement of the first lifting cylinder, wherein the displacement difference is the difference between the displacement of the main cylinder and the displacement of the first lifting cylinder, and the main cylinder is one of the plurality of lifting cylinders. The control unit is configured to control the extension and retraction speed of the first lifting cylinder by adjusting the first channel input value when the controller receives an instruction that the displacement difference is not equal to zero, based on the displacement difference. The control unit adjusts the first channel input value according to the displacement difference and the adjustment limit, and during the adjustment process, the adjusted value of the first channel input value is not greater than the adjustment limit. The adjustment limit is obtained based on the adjustment base of the first proportional valve and the input range of the first input channel. The adjustment base is the first channel input value corresponding to the opening size of the first proportional valve when the lifting platform is raised and lowered at the target speed. The adjustment method for the first channel input value is as follows: If the displacement difference s is greater than zero, and the ratio of the displacement difference to the minimum speed adjustment value is greater than the minimum time c, the controller controls the first channel input value to increase by the adjustment limit; or, if the displacement difference s is less than zero, and the ratio of the displacement difference to the minimum speed adjustment value is less than the negative of the minimum time c - c, the controller controls the first channel input value to decrease by the adjustment limit; or, if the displacement difference s is less than zero and the ratio of the displacement difference to the minimum speed adjustment value is greater than the negative of the minimum time c - c, the controller controls the first channel input value to decrease linearly with time, and controls the first channel input value not to exceed the adjustment limit; or, if the displacement difference s is greater than zero and less than the ratio of the displacement difference to the minimum speed adjustment value, and greater than the minimum time c, the controller controls the first channel input value to increase linearly with time, and controls the first channel input value not to exceed the adjustment limit.

5. A computer device, characterized in that, The computer device includes a processor and a memory configured to store executable instructions of the processor; the processor is configured to perform the control method of the lifting platform according to any one of claims 1 to 3.

6. A computer storage medium storing computer instructions thereon, characterized in that, When the computer instructions are executed by the processor, they implement the control method of the lifting platform according to any one of claims 1 to 3.

Images