A working range control method and system

Abstract

The present invention relates to the field of work platform control technology, specifically a working range control method and system, in which a first telescopic arm is used to drive a work platform to rise in a vertical direction. When the length and angle of the first telescopic arm exceed the set working range limit and the work platform has not reached the target position, the second telescopic arm is actuated and cooperates with the first telescopic arm to continue to drive the work platform to rise in the vertical direction until it reaches the target position. When the first telescopic arm does not exceed the set working range limit, the posture of the first telescopic arm is corrected according to the set angle difference. During the coordinated movement of the first telescopic arm and the second telescopic arm, the posture of the second telescopic arm is corrected according to the set angle difference, and the posture of the first telescopic arm is further corrected according to the height change of the work platform from the ground. This method solves the limitations of the traditional control process and stably increases the working range of the work platform within a safe range through the coordinated movement and posture correction of the two telescopic arms, thereby expanding the operating range of the platform.

Description

Technical Field

[0001] The present invention relates to the technical field of work platform control, and specifically to a working range control method and system. Background Art

[0002] The statements in this part only provide background technical information related to the present invention, and do not necessarily constitute prior art.

[0003] The articulated boom aerial work platform is a commonly used device in the engineering industry, mainly including straight boom type and articulated boom type. In the boom structure of the straight boom type, the main boom is lifted / lowered under the action of the luffing cylinder and extended / retracted under the action of the telescopic cylinder. The boom structure of the articulated boom type consists of multiple booms and link mechanisms. The combined actions of the whole machine often require the cooperation of the boom and multiple link mechanisms, and the control logic is more complex. Its unique articulated boom structure can cross obstacles for operation. For example, when performing street lamp maintenance or building facade operation on a street with obstacles such as trees and street lamps, it can flexibly extend and adjust its position to reach working points that are difficult for other equipment to reach. The horizontal extension distance is relatively large, and it can effectively cover a larger operation area.

[0004] The working range of the articulated boom aerial work platform refers to the maximum distance that the platform can extend in the horizontal and vertical directions. The factors affecting the working range mainly include: boom length and number of sections, boom structure and material, vehicle stability and control method, etc. Among them, the control process of the working range is the key factor.

[0005] The prior art CN202410138449.8 proposes an aerial work platform and its boom vertical operation control method and readable storage medium. The deficiencies of this method are as follows:

[0006] (1) The working conditions applicable to this method are limited. Due to relying on a laser rangefinder and preset safety monitoring values, it is only applicable to a fixed wall surface, and there are no a large number of protrusions, depressions, cracks or extreme roughness on the wall surface. Otherwise, the signals reflected by the laser beam may be very messy, resulting in large calculation errors. When there are obstructions or obstacles on the construction wall surface, such as trees and railings, the laser beam cannot directly reach the wall surface and be reflected back, so it is naturally impossible to measure. When the construction wall surface is a transparent or semi-transparent wall surface, such as a transparent or semi-transparent wall surface like glass, the laser beam may penetrate rather than be completely reflected, making it impossible for the rangefinder to accurately measure the distance based on the reflected signal. These factors can all cause the control method of this solution to fail.

[0007] (2) This solution does not consider the influence of different loads on the working range. As a device that lifts heavy objects and construction workers to a specific height, the load is a crucial factor for an aerial work platform. During the design process, to ensure the stability of the whole machine, the working range is designed according to different loads. Only in this way can the safety of construction workers be guaranteed.

[0008] (3) This solution ignores the errors caused by the boom angle and length, which will affect the control effect of this solution.

[0009] The prior art CN201210097291.1 proposed a trajectory control device for the operation platform of an aerial work vehicle. This solution has the following deficiencies:

[0010] (1) Although this solution considers the influence of the load on the working range and places certain restrictions on the horizontal extension and retraction and the vertical lifting and lowering, it increases the control difficulty to a certain extent and affects the use effect described by this solution. In addition, this solution only considers a single load and does not consider the influence of multiple loads.

[0011] (2) Restricted by the boom structure, this solution is not applicable to complex working conditions. When the working range is restricted, walking adjustment is still required to achieve the predetermined effect.

[0012] (3) This solution sets a dead zone to avoid oscillation caused by too fast switching of the cylinder extension and retraction. However, this is based on the premise of reducing the position control accuracy. Therefore, the selection of the dead zone parameters will affect the use effect.

[0013] In summary, the working range control methods for aerial work platforms proposed by the prior art have limitations and it is difficult to give full play to the advantages of the aerial work platform itself. Summary of the Invention

[0014] In view of the problems raised in the background art, the present invention provides a working range control method and system. Through the coordinated movement of the first telescopic boom and the second telescopic boom, the angle and length signals are processed, and the working range of the workbench can be stably increased within a safe range, expanding the operating range of the platform and giving full play to the performance of the platform.

[0015] To achieve the above object, the present invention adopts the following technical solutions:

[0016] The first aspect of the present invention provides a working range control method, which is applied to a boom-type aerial work platform. The boom-type aerial work platform includes a workbench, the workbench is hinged to the head end of the first telescopic boom, the tail end of the first telescopic boom is hinged to the head end of the second telescopic boom, and the tail end of the second telescopic boom is hinged to the turntable; the method includes the following steps:

[0017] The movement of the first telescopic arm drives the workbench to rise or fall vertically. When the length and angle of the first telescopic arm exceed the set working range limit and the workbench has not reached the target position, the second telescopic arm moves and cooperates with the first telescopic arm to continue driving the workbench to rise or fall vertically until the target position is reached;

[0018] During the cooperative movement of the first telescopic arm and the second telescopic arm, correct the attitude of the second telescopic arm, and further correct the attitude of the first telescopic arm according to the change in the height of the workbench from the ground.

[0019] Furthermore, the boom-type aerial work platform is in the set working position in the initial state, and the first telescopic arm is in a horizontal state, and the second telescopic arm is at a set angle.

[0020] Furthermore, the workbench maintains a horizontal state during the rising process.

[0021] Furthermore, when the length and angle of the first telescopic arm do not exceed the set working range limit, correct the attitude of the first telescopic arm according to the set angle difference; specifically:

[0022] When the first telescopic arm drives the workbench to move vertically, determine the functional relationship between the length and angle of the first telescopic arm;

[0023] Taking the initial angle of the first telescopic arm α0 and the first set of angle data α1 as a reference, calculate the difference between the two angles as Δ α01 , the difference between the angle αi corresponding to the current attitude and the angle αi-1 corresponding to the previous attitude is Δαi When | Δαi - Δα 01 | exceeds the set value, the downward deflection of the first telescopic arm causes an error. According to the obtained functional relationship, determine the corrected length of the first telescopic arm as Li = f ( αi + Δαi ), and the angle is αi + Δαi .

[0024] Furthermore, the functional relationship between the length and angle of the first telescopic arm is as shown in the following formula:

[0025] ;

[0026] In the formula, L i is the length of the first telescopic arm, i = 0, 1, 2, ……, n; αi is the angle between the first telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n.

[0027] Further, during the coordinated movement of the first telescopic arm and the second telescopic arm, correct the attitude of the second telescopic arm; specifically:

[0028] Taking the angle of the second telescopic arm as the independent variable, determine the functional relationship between the length and the angle of the second telescopic arm;

[0029] The initial angle of the second telescopic arm β0 and the first set of angle data β1 The difference between them is Δβ01 , and the angle corresponding to the current attitude βi and the angle corresponding to the previous attitude βi-1 The difference between them is Δβi When | Δβi - Δβ01 | exceeds the set value, the downward deflection of the second telescopic arm brings errors;

[0030] According to the obtained functional relationship, determine that the corrected length of the second telescopic arm is Hi = f ( βi + Δβi ), and the angle is βi + Δβi .

[0031] Further, the functional relationship between the length and the angle of the second telescopic arm is as shown in the following formula:

[0032] ;

[0033] In the formula, H i is the length of the second telescopic arm, i = 0, 1, 2, ……, n; β i is the angle between the second telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n.

[0034] Further, during the coordinated movement of the first telescopic arm and the second telescopic arm, according to the change in the height of the workbench from the ground, correct the attitude of the first telescopic arm, specifically:

[0035] Determine the functional relationship between the first telescopic arm and the second telescopic arm;

[0036] According to the change in the height of the workbench from the ground, determine the movement direction of the workbench. When the actual movement direction of the workbench is different from the required movement direction, use the angle of the second telescopic arm and the obtained functional relationship to correct the angle of the first telescopic arm. The angle correction value of the first telescopic arm is Δα 1i = Δβ i , and the revised angle is α 1i + Δα 1i , Δβ i = β i -β i-1 , β i is the angle between the current posture of the second telescopic arm and the horizontal reference plane, β i-1 is the angle between the previous posture of the second telescopic arm and the horizontal reference plane, α 1i is the angle between the first telescopic arm and the horizontal reference plane during the coordinated movement.

[0037] Further, the functional relationship between the first telescopic arm and the second telescopic arm is as shown in the following formula:

[0038] ;

[0039] In the formula, L i is the length of the first telescopic arm 1, i = 0, 1, 2,..., n; α i is the angle between the first telescopic arm 1 and the horizontal reference plane, i = 0, 1, 2,..., n; H i is the length of the second telescopic arm, i = 0, 1, 2,..., n; β i is the angle between the second telescopic arm and the horizontal reference plane, i = 0, 1, 2,..., n; y i is the height of the workbench from the ground.

[0040] The second aspect of the present invention provides a working range control system, including;

[0041] The first angle detection unit is used to obtain the angle of the first telescopic arm;

[0042] A second angle detection unit for obtaining the angle of the second telescopic arm;

[0043] A first length detection unit for obtaining the length of the first telescopic arm;

[0044] A second length detection unit for obtaining the length of the second telescopic arm;

[0045] A control unit for extracting the signals provided by all angle detection units and length detection units, and realizing the control of the working range of the boom-type aerial work platform through a pre-stored working range control method.

[0046] Compared with the prior art, the above one or more technical solutions have the following beneficial effects:

[0047] 1. First, the first telescopic arm drives the workbench to rise vertically. When the first telescopic arm exceeds its own working range limit value, then the coordinated movement of the second telescopic arm and the first telescopic arm is used to continue driving the workbench to rise vertically, which can increase the working range of the workbench within the safe range, expand the working range of the platform, and give full play to the performance of the platform.

[0048] 2. During the process of driving the workbench to rise vertically, the influence of different loads on the working range is considered. The two telescopic arms deflect differently under different loads, and the deflection is reflected in the angle changes of the two telescopic arms, that is, a corresponding angle difference is generated. When the first telescopic arm does not exceed its own working range and only the first telescopic arm is used to drive the workbench to rise, the angle difference generated by the deflection of the first telescopic arm is used to correct its own telescopic length. When the two telescopic arms move in coordination, the angle difference generated by the deflection of the second telescopic arm is used to correct its own telescopic length. At the same time, the height change of the workbench from the ground is used to correct the attitude (length and angle) of the first telescopic arm, and the angle change of the second telescopic arm is also used to correct the angle of the first telescopic arm, so that the rising action of the workbench can be stably provided by the two coordinated telescopic arms.

[0049] 3. During the process of the two telescopic arms driving the workbench to move vertically through coordinated movement, the two telescopic arms work within their respective plane ranges and will not exceed the vertical facade within a certain distance around the workbench. The vertical facade can be regarded as an obstacle. Compared with the traditional control process that requires the aerial work platform to move back and forth to adjust the position to ensure that it will not hit the obstacle, after the working platform of this solution is in a determined position, the workbench will rise or fall vertically in the space between the two vertical facades, reducing the operations required to adjust the position.

[0050] 4. It circumvents the laser rangefinder in the traditional solution. By using the length changes and angle changes of the two telescopic arms themselves, it adjusts the posture of the workbench, reduces the influence of the working environment, can adapt to a more complex working environment, and avoids the inconvenience and errors brought by various rangefinders. Brief Description of the Drawings

[0051] The accompanying drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0052] Figure 1 It is a schematic diagram of the working range control process provided by one or more embodiments of the present invention;

[0053] Figure 2 It is a schematic diagram of the boom structure provided by one or more embodiments of the present invention;

[0054] Figure 3 It is a simplified schematic diagram of the boom structure provided by one or more embodiments of the present invention;

[0055] Figure 4 It is a schematic diagram during the boom lifting the workbench provided by one or more embodiments of the present invention;

[0056] Figure 5 It is a schematic diagram of the correction process when the boom lifts the workbench provided by one or more embodiments of the present invention;

[0057] Figure 6 It is a schematic diagram of the effect of increasing the working range of the workbench provided by one or more embodiments of the present invention.

[0058] In the figures: 1. First telescopic arm, 2. Second telescopic arm, 3. Turntable, 4. Workbench, 5. First connecting rod, 6. Second connecting rod, 7. First luffing oil cylinder, 8. Second luffing oil cylinder, 9. First telescopic oil cylinder, 10. Second telescopic oil cylinder, 101. First angle detection unit, 102. First length detection unit, 201. Second angle detection unit, 202. Second length detection unit, 401. Control unit. Detailed Description of the Preferred Embodiments

[0059] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0060] It should be noted that the following detailed descriptions are all exemplary and are intended to provide a further description of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0061] In addition to the solutions related to the control methods of aerial work platforms listed in the background art, some existing technologies have similar limitations.

[0062] For example, CN201110027467.1 proposes a working trajectory control method for an aerial work platform. This solution also does not consider the influence of different loads on the working amplitude and ignores the errors caused by the boom angle and length, which will seriously affect the effect of the control method described in this patent. This patent is also restricted by the boom structure and is not suitable for complex working conditions. When the working range is restricted, walking adjustment is required to achieve the predetermined effect.

[0063] For example, CN202410220391.1 proposes a method for solving the position of the end hinge point and trajectory control of a straight boom aerial work platform. This solution requires multiple coordinate extraction devices to be installed on the boom to extract the position coordinates of discrete points. In the actual working process, there are multiple factors such as boom shaking, oil cylinder oscillation, and wind load, resulting in large errors in the extracted discrete point data. The boom in the embodiment of this patent includes a telescopic boom, a luffing link, etc., and the telescopic boom and the link are in a linkage relationship, that is, the movement of the luffing link is affected by the movement of the telescopic boom luffing oil cylinder, and the speed, acceleration, angle, etc. of the link hinge point are affected by the telescopic boom. Finally, this solution still calculates the angle change of the link using the angle and length of the telescopic boom. In addition, this solution is relatively complex as a whole, suitable for the structural design link, and not conducive to practical application.

[0064] The greater the working amplitude of the aerial work platform, the greater the possibility that the center of gravity of the boom (including the load) deviates from the tipping line. When it exceeds a certain range, the dangerous moment generated by gravity will cause the whole vehicle to lose balance and trigger a tipping accident. Therefore, the influence of stability needs to be considered in the design. Usually, the overall stability of the machine is calculated during the design, and the maximum working amplitude is limited through the data of angle, length, weight, etc. collected by each control unit. When the boom extends to a certain length or angle, its further extension or lowering will be restricted to ensure that the whole machine can maintain stability at different working amplitudes and avoid tipping due to exceeding the working amplitude. The aerial work platform as a whole is a power system, and each boom can be regarded as an independent power system. Each movement of the boom is carried out under the action of hydraulic cylinders and control units. The common aerial work platform is of a single boom structure, that is, a single power system.

[0065] The working amplitude control method proposed in this solution is applicable to aerial work platforms with a double boom power system. By designing a double telescopic boom structure and controlling the length and angle of each boom power system, the working amplitude of the workbench can be effectively increased.

[0066] Embodiment 1:

[0067] Simplify the boom structure of the aerial work platform. The simplified boom structure includes a first telescopic boom and a second telescopic boom. The head end of the first telescopic boom is hinged to the workbench, and the tail end is hinged to the head end of the second telescopic boom. The tail end of the second telescopic boom is hinged to the turntable. The simplified boom structure has three hinge points. Among them, the workbench always maintains a horizontal state. According to the current position of the workbench, control and correct the angles of the other two hinge points and the lengths of the two telescopic booms.

[0068] As shown in Figure 1 , a working range control method includes the following steps:

[0069] In the initial state, the first telescopic boom is in a horizontal state, and the second telescopic boom is at a set angle; the first telescopic boom drives the entire boom to move and the workbench to rise by changing its length and angle (angle relative to the horizontal plane);

[0070] During the rising process, continuously obtain the length and angle of the first telescopic boom. If the length and angle exceed the working range limit of the first telescopic boom during the boom movement and the workbench has not yet reached the set height position, perform a combined action of the first telescopic boom and the second telescopic boom; if the length and angle do not exceed the working range limit, continue to move;

[0071] The combined action of the first telescopic boom and the second telescopic boom is specifically: the first telescopic boom and the second telescopic boom continue to drive the workbench to rise by changing their lengths and angles (angles relative to the horizontal plane);

[0072] During the rising of the workbench, obtain the attitude of the workbench, and judge whether the workbench moves in a predetermined attitude. If so, continue to move; if not, adjust the attitude of the workbench according to the height of the workbench from the ground in combination with the lengths and angles of the first telescopic boom and the second telescopic boom.

[0073] The working range control method given in this embodiment is applied to the aerial work platform as shown in Figure 2 .

[0074] As shown in Figure 2 , the aerial work platform includes a turntable, a boom and a workbench. The boom includes a first telescopic boom 1 and a second telescopic boom 2. The first hinge point of the second telescopic boom 2 is connected to the turntable 3, the second hinge point of the second telescopic boom 2 is connected to the first hinge point of the first telescopic boom 1, and the second hinge point of the first telescopic boom 1 is connected to the workbench 4.

[0075] As a further implementation method, the workbench is by default a mechanism that can achieve horizontal through hydraulic leveling or electric leveling, etc., which is a mature existing technology and will not be elaborated in this embodiment.

[0076] As shown in Figure 2As shown in the figure, the aerial work platform further includes a first connecting rod 5 and a second connecting rod 6. The first telescopic arm 1 is movably connected to the two connecting rods through a first luffing oil cylinder 7, and the second telescopic arm 2 is movably connected to the turntable 3 through a second luffing oil cylinder 8.

[0077] When the rodless cavity of the first luffing oil cylinder 7 is filled with oil, the first telescopic arm 1 realizes upward luffing. When the rod chamber of the first luffing oil cylinder 7 is filled with oil, the first telescopic arm 1 realizes downward luffing. Similarly, when the rodless cavity of the second luffing oil cylinder 8 is filled with oil, the second telescopic arm 2 realizes upward luffing. When the rod chamber of the second luffing oil cylinder 8 is filled with oil, the second telescopic arm 2 realizes downward luffing. The achieved effect is the change in the angle of the telescopic arm.

[0078] As a further implementation manner, the first connecting rod 5 and the second connecting rod 6 are structures connecting the two telescopic arms, and are two rod-shaped structural members connected by a hinged manner. They are mature existing technologies, and the specific structural form of the connecting rod is not described in detail in this embodiment.

[0079] As a further implementation manner, the first luffing oil cylinder 7 and the second luffing oil cylinder 8 are components for providing power when realizing the angle change of the two telescopic arms, and belong to a type of hydraulic cylinder. They are mature existing technologies, and the specific structural form of the luffing oil cylinder is not described in detail in this embodiment.

[0080] As a further implementation manner, when the telescopic arm is a two-section arm structure, it realizes extension and retraction through an internal telescopic oil cylinder. When the telescopic arm is a three-section arm, four-section arm or even more-section arm structure, the telescopic mechanism is composed of a telescopic oil cylinder and a steel wire rope or a chain. The achieved effect is the extension and retraction of the telescopic arm, that is, the change in the length of the telescopic arm.

[0081] In this embodiment, a first telescopic oil cylinder 9 is arranged inside the first telescopic arm 1. When the rodless cavity of the first telescopic oil cylinder 9 is filled with oil, the first telescopic arm 1 extends. When the rod chamber of the first telescopic oil cylinder 9 is filled with oil, the first telescopic arm 1 retracts. Similarly, a second telescopic oil cylinder 10 is arranged inside the second telescopic arm 2. When the rodless cavity of the second telescopic oil cylinder 10 is filled with oil, the second telescopic arm 2 extends. When the rod chamber of the second telescopic oil cylinder 10 is filled with oil, the second telescopic arm 2 retracts. The telescopic oil cylinder belongs to a type of hydraulic cylinder and is also a mature existing technology.

[0082] The realization of the working range control method also requires the following devices:

[0083] A first angle detection unit 101 installed on the first telescopic arm 1 for detecting the angle of the first telescopic arm 1;

[0084] A second angle detection unit 201 installed on the second telescopic arm 2 for detecting the angle of the second telescopic arm 2;

[0085] The first length detection unit 102 installed on the first telescopic boom 1 is used to detect the length of the first telescopic boom 1;

[0086] The second length detection unit 202 installed on the second telescopic boom 2 is used to detect the length of the second telescopic boom 2;

[0087] The control unit 401 installed on the workbench 4 is used to read the signals provided by detection units such as the angle and length, and control the working range through the pre-stored working range control method.

[0088] As a further implementation manner, the angle signal obtained by the angle detection unit can be the angle information based on the ground, or the angle information between the two telescopic booms and the angle information between the second telescopic boom 2 and the plane where the turntable 3 is located.

[0089] To facilitate the understanding of this solution, the boom structure is simplified. The simplified boom structure is as Figure 3 shown, including the first telescopic boom 1 and the second telescopic boom 2. The head end of the first telescopic boom 1 is hinged to the workbench, and the tail end is hinged to the head end of the second telescopic boom 2. The tail end of the second telescopic boom 2 is hinged to the turntable ( Figure 3 in which the turntable has been hidden). The simplified boom structure has three hinge points. Among them, the workbench always remains horizontal. Then, the angle of the hinge point between the first telescopic boom 1 and the workbench can be controlled by using the existing mature algorithm. The working range control method of this embodiment controls the angles of the other two hinge points and the lengths of the two telescopic booms according to the current position of the workbench.

[0090] The working range control method given in this embodiment processes the signals fed back by the angle detection unit and the length detection unit through the coordinated movement of the first telescopic boom 1 and the second telescopic boom 2, and can stably increase the working range of the workbench within a safe range. The specific steps are as follows:

[0091] Step 1 Preparation. The operator adjusts the angle of the first telescopic boom 1 to horizontal (0°) through the control unit 401 of the workbench 4, adjusts the second telescopic boom 2 to the retracted state (the angle during retraction is a fixed value. When the second telescopic boom 2 descends to the oil cylinder limit position, the angle at this time is the retracted angle, which can also be considered as the set angle), moves the whole vehicle to a suitable position (a position that does not obstruct traffic and is convenient for construction), and adjusts the distance between the workbench and the construction surface (which can be a specific solid wall surface or a specific position) through the first telescopic oil cylinder 9. The expected effect is that the workbench 4 moves vertically upward along the construction surface.

[0092] Step 2 Execution.

[0093] Step 2.1. Under the extension and luffing actions of the first telescopic arm 1, the workbench starts to rise in the vertical direction of the construction plane. As Figure 4 shown, the first angle detection unit 101 continuously detects the data signal of the angle change of the first telescopic arm 1 and feeds the angle data signal back to the control unit, recorded as α 0 、α 1 …α i …α n , the first length detection unit 102 continuously detects the data signal of the length change of the first telescopic arm 1 and feeds the length data signal back to the control unit 401, recorded as L 0 、L 1 … L i …L n , the working range limit values recorded in the control unit 401 are respectively α max ( α max ≤70°), L max ( L max ≤15m). When α i ≤ α max and L i ≤ L max , it is considered that the working range is not exceeded and it is safe to continue working. When α max < α i or L max < L i , it is considered that the working range has been exceeded and it is unsafe to continue working.

[0094] When α i ≤ α max and L i ≤ L max , it is still within the working range of the first telescopic arm 1. Then the first telescopic arm 1 continues to move and work. The specific implementation method is as follows:

[0095] Taking the angle of the first telescopic arm 1 as the independent variable, the angle range is 0° ≤ α i ≤ αmax , according to the mathematical relationship during the movement of the boom, the functional relationship between the length and the angle of the first telescopic boom 1 can be found when the first telescopic boom 1 drives the workbench to move in the vertical direction L i = f ( α i ), as shown in the following formula:

[0096] ;

[0097] In the formula, L i —— the length of the first telescopic boom, i = 0, 1, 2, ……, n;

[0098] α i —— the angle between the first telescopic boom and the horizontal reference plane, i = 0, 1, 2, ……, n.

[0099] As the luffing angle and the extended length of the first telescopic boom 1 increase, the downward deflection of the first telescopic boom 1 will cause errors. Here, the angle difference is used to compensate for the errors in length and angle. The first set of angle data during the movement of the first telescopic boom 1 is used as the reference angle to correct the difference between the current angle and the previous angle.

[0100] Specifically: taking the first set of data α 0 、α 1 detected by the angle detection unit of the first telescopic boom 1 as the reference, where α 0 is the initial angle of the first telescopic boom 1, and the difference between the two angles in the first set of data is denoted as Δα 01 , and the difference when the luffing angle is α i-1 、α i is Δα i . When 0.5° ≤ | Δα i -Δα 01 | ≤ 2°, it is considered that the error is small and can be ignored; when 3° < | Δα i -Δα 01 |, it is considered that the error is large. At this time, the length of the telescopic boom is L i = f ( α i + Δα i ), and the angle isα i + Δα i 。

[0101] At this time, the control unit 401 controls the rodless cavity of the first luffing cylinder 7 to be filled with oil. At the same time, the rodless cavity of the first telescopic cylinder 9 is filled with oil. The effect is that the workbench 4 changes in length and angle simultaneously under the cooperation of the two cylinders, causing the workbench to move vertically upward along the construction surface Y1 until it reaches the predetermined position. As Figure 4 shown.

[0102] Step 2.2. When α max < α i or L max < L i it is considered that the current position of the workbench has caused the first telescopic arm 1 to exceed its own working amplitude, and the workbench 4 needs to be controlled in cooperation with the first telescopic arm 1 and the second telescopic arm 2 to continue moving to the set position. The specific implementation method is as follows.

[0103] As Figure 5 shown, continue to toggle the control button of the workbench 4. The second angle detection unit 201 detects the data signal of the angle change of the second telescopic arm 2 in real time and feeds the angle data signal back to the control unit 401, recorded as β 0 、β 1 …β i … β n , and the second length detection unit 202 detects the data signal of the length change of the second telescopic arm 2 in real time and feeds the length data signal back to the control unit 401, recorded as H 0 、H 1 …H i …H n .

[0104] Taking the angle of the second telescopic arm 2 as the independent variable, according to the mathematical relationship in the movement process of the boom, the functional relationship between the boom length and the angle H i = f ( β i ), is as follows:

[0105] ;

[0106] In the formula, H i—— The length of the second telescopic arm, i = 0, 1, 2, ……, n;

[0107] β i —— The angle between the second telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n.

[0108] As the luffing angle and the extended length of the second telescopic arm 2 increase, the downward deflection of the second telescopic arm 2 will also cause errors. Error compensation is also required here. Taking the first set of data detected by the second angle detection unit 201 β 0 、β 1 as the reference, the difference between the two angles is denoted as Δβ 01 , and the difference when the luffing angle is β i-1 、β i is Δβ i , when 0.5° ≤ | Δβ i -Δβ 01 | ≤ 2°, it is considered that the error is small and can be ignored; when 3° < | Δβ i -Δβ 01 |, it is considered that the error is large. At this time, the telescopic arm length is H i = f ( β i + Δ β i ), and the angle is β i + Δβ i .

[0109] At this time, while the control unit 401 controls the oil inlet of the rodless cavity of the second luffing oil cylinder 8, the oil inlet of the rodless cavity of the second telescopic oil cylinder 10 is also controlled. The hinge point between the second telescopic arm 2 and the first telescopic arm 1 moves vertically upward along the plane Y1. Due to the special structure, if the first telescopic arm 1 does not move cooperatively at this time, the workbench 4 will move in the opposite direction, as shown by the dotted line part in Figure 5 , so step 2.3 is carried out.

[0110] Step 2.3. The first angle detection unit 101 continuously detects the data signal of the angle change of the first telescopic arm 1 and feeds the angle data signal back to the control unit 401, which is recorded as α 10 、α11 …α 1i …α 1n , that is, the angle of the first telescopic arm 1 during the coordinated movement. During the coordinated movement of the first telescopic arm and the second telescopic arm, the movement of the second telescopic arm will drive the first telescopic arm. Therefore, during the coordinated movement, the revised formula for the first telescopic arm in "Step 2.1" is not used for revision. Instead, the attitude of the first telescopic arm is judged according to the height of the workbench from the ground, and then the revision is carried out. When the revised value is Δα 1i =Δβ i , that is, no matter how much the second telescopic arm changes, the first telescopic arm will change the same amount, which can make the first telescopic arm continue to maintain upward vertical movement and the distance between the workbench and the construction surface remains unchanged.

[0111] Specifically: According to the mathematical relationship during the movement of the boom, the functional relationship between the first telescopic arm 1 and the second telescopic arm 2 y i = f ( β i ), as shown in the following formula:

[0112] ;

[0113] In the formula, L i ——The length of the first telescopic arm 1, i = 0, 1, 2, ……, n;

[0114] α i ——The angle between the first telescopic arm 1 and the horizontal reference plane, i = 0, 1, 2, ……, n;

[0115] H i ——The length of the second telescopic arm 2, i = 0, 1, 2, ……, n;

[0116] β i ——The angle between the second telescopic arm 2 and the horizontal reference plane, i = 0, 1, 2, ……, n;

[0117] y i ——The height of the workbench from the ground.

[0118] Judge whether to correct the attitude of the first telescopic arm 1 according to the difference in the height of the workbench 4 from the ground.

[0119] Δy i = y i - y i-1 When Δy i ≤ -0.2 m, the workbench 4 moves downward. For the workbench in this embodiment, the required movement direction is vertically upward, while the actual movement direction is downward. At this time, it is necessary to correct the attitude of the first telescopic arm 1 during the movement, and use the angle of the second telescopic arm 2 to adjust the angle of the first telescopic arm 1. At this time Δβ i =β i -β i-1 , so the angle revision value of the first telescopic arm is Δα 1i = Δβ i , and the angle is α 1i + Δα 1i , as shown in Figure 5 .

[0120] According to the structural characteristics, when the second telescopic arm moves upward, it will drive the first telescopic arm to move downward; when the second telescopic arm moves downward, it will drive the first telescopic arm to move upward.

[0121] For example, when the angle of the first telescopic arm reaches the maximum angle, the two telescopic arms move in coordination. When the angle of the second telescopic arm changes upward by 10 degrees, if not corrected, due to the characteristics of the boom structure itself, the first telescopic arm will instead change downward by 10 degrees, thus driving the workbench to move downward, and the workbench cannot maintain a vertically upward movement, and the distance between the workbench and the construction plane will change, which does not meet the requirements. Therefore, a revision value of Δα 1i =Δβ i is set here, that is, during the vertical upward movement of the workbench, when the second telescopic arm changes upward, the first telescopic arm also changes upward, and the amounts of upward change of the two telescopic arms are equal, which can enable the first telescopic arm to maintain the state of the workbench moving vertically upward while keeping the angle unchanged, and the distance between the workbench and the construction surface remains unchanged.

[0122] It can be understood that this embodiment takes the vertical upward movement of the workbench as an example, and the control process also includes the vertical downward movement of the workbench. When -0.2 m < Δ y i , as the judgment for downward movement, when the workbench moves downward, the amount of downward change of the second telescopic arm is equal to the amount of downward change of the first telescopic arm, ensuring that the workbench maintains a vertical downward movement.

[0123] For example, for the device where the workbench moves vertically downward, the current angle of the first telescopic arm is 50 degrees. When the two telescopic arms start to move in coordination and the angle of the second telescopic arm changes downward by 10 degrees, if the first telescopic arm is not corrected, due to the characteristics of the boom structure itself, the first telescopic arm will change upward by 10 degrees based on its original position, that is, it will become 60 degrees. Therefore, the correction makes the second telescopic arm change downward, and the first telescopic arm also changes downward, and the amounts of downward change of the two telescopic arms are equal, so as to maintain the state of the workbench moving vertically downward.

[0124] In the solution given in this embodiment, the laser rangefinder is avoided, and the attitude of the workbench is adjusted by using the length change and angle change of the two telescopic arms themselves, which can adapt to a more complex working environment and avoid the inconvenience and errors brought by various rangefinders.

[0125] The solution given in this embodiment takes into account the influence of different loads on the working range. The two telescopic arms have different deflections under different loads, and the deflections are reflected in the angle changes of the two telescopic arms. Then, the angle changes of the first telescopic arm and the second telescopic arm are used to compensate for the deflection amount. When the two telescopic arms move in coordination, in addition to using the angle change of the second telescopic arm to compensate for the deflection amount, the attitude (angle) of the first telescopic arm is corrected by using the height change of the workbench from the ground, so that the workbench always maintains a vertical upward or downward movement. Instead of using a complex coordinate extraction device, a simple and common length and angle detection device is adopted, and the deflection amount is compensated through the relationship between length and angle. The deflection amounts caused by different loads are different and can be manifested as angle changes.

[0126] In the solution given in this embodiment, through the coordinated movement of the first telescopic arm and the second telescopic arm, the angle and length signals are processed, and the working range of the workbench can be stably increased within a safe range, so that the working range of the platform is expanded, and the performance of the platform is fully exerted. Through the control of the two telescopic arms, the movement is more flexible, and there are more degrees of freedom during the movement process, such as Figure 6 as shown.

[0127] During the process that the two telescopic arms drive the workbench to move vertically through coordinated movement, the two telescopic arms work within their respective plane ranges and will not exceed the vertical facade within a certain distance around the workbench. The vertical facade can be regarded as an obstacle. Figure 5 as shown, Figure 5 The vertical facades Y1 and Y2 in can be regarded as obstacles. In the traditional control process, the aerial work platform needs to move back and forth to adjust the position to ensure that it will not hit the obstacle, while the control method given in this embodiment does not require moving back and forth. After the position of the work platform is determined, the workbench will vertically rise or fall in the space between the two vertical facades Y1 and Y2, reducing the operations required to adjust the position.

[0128] Embodiment 2:

[0129] A working range control system, comprising:

[0130] A first angle detection unit for obtaining the angle of the first telescopic boom;

[0131] A second angle detection unit for obtaining the angle of the second telescopic boom;

[0132] A first length detection unit for obtaining the length of the first telescopic boom;

[0133] A second length detection unit for obtaining the length of the second telescopic boom;

[0134] A control unit for extracting the signals provided by all the angle detection units and length detection units, and realizing the control of the working range of the articulated aerial work platform through the pre-stored working range control method.

[0135] By the coordinated movement of the first telescopic boom and the second telescopic boom, processing the angle and length signals, the working range of the workbench can be stably increased within a safe range, the working range of the platform can be expanded, and the performance of the platform can be fully exerted.

[0136] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A working range control method is applied to a boom-type aerial work platform. The boom-type aerial work platform includes a workbench, the workbench is hinged to the head end of the first telescopic boom, the tail end of the first telescopic boom is hinged to the head end of the second telescopic boom, and the tail end of the second telescopic boom is hinged to the turntable; characterized in that, The following steps are involved: The first telescopic arm moves to drive the workbench to rise or fall in the vertical direction. When the length and angle of the first telescopic arm exceed the set working range limit and the workbench has not reached the target position, the second telescopic arm moves and cooperates with the first telescopic arm to continue to drive the workbench to rise or fall in the vertical direction until it reaches the target position. During the coordinated movement of the first telescopic arm and the second telescopic arm, the posture of the second telescopic arm is corrected, and the posture of the first telescopic arm is further corrected according to the change in the height of the workbench from the ground; The posture of the first telescopic arm is further corrected according to the height change of the workbench from the ground, specifically: determining a functional relationship between the first telescopic arm and the second telescopic arm; The movement direction of the workbench is determined according to the change in the height of the workbench from the ground. When the actual movement direction of the workbench is different from the required movement direction, the angle of the first telescopic arm is corrected using the angle of the second telescopic arm and the obtained functional relationship. The revised angle value of the first telescopic arm is Δα1i=Δβi, and the revised angle is α1i+Δα1i, Δβi=βi-βi-1, βi is the angle between the current posture of the second telescopic arm and the horizontal reference plane, βi-1 is the angle between the previous posture of the second telescopic arm and the horizontal reference plane, and α1i is the angle between the first telescopic arm and the horizontal reference plane during the coordinated movement.

2. The working range control method according to claim 1, characterized in that The boom-type aerial work platform is in a set working position in an initial state, with the first telescopic arm in a horizontal state and the second telescopic arm at a set angle.

3. A working range control method according to claim 1, characterized in that, The table remains horizontal during vertical movement.

4. The working range control method according to claim 1, wherein When the length and angle of the first telescopic arm do not exceed the set working range limit, the posture of the first telescopic arm is corrected according to the set angle difference; specifically: When the first telescopic arm drives the workbench to move in the vertical direction, determining the functional relationship between the length and angle of the first telescopic arm; With the initial angle of the first telescopic arm α0 and the first set of angle data α1 as a reference, calculate the difference between the two angles as Δα01 . The angle corresponding to the current posture αi and the angle corresponding to the previous posture αi-1 The difference between them is Δαi . When | Δαi-Δα01 | exceeds the set value, the downward deflection of the first telescopic arm causes an error. According to the obtained functional relationship, determine the corrected length of the first telescopic arm as Li = f ( αi + Δαi ), and the angle is αi + Δαi .

5. The working range control method according to claim 4, characterized in that, The functional relationship between the length and angle of the first telescopic arm is shown in the following formula: ； Wherein, L i is the length of the first telescopic arm, i = 0, 1, 2, ……, n; α i is the angle between the first telescopic arm and the horizontal reference plane, i = 0, 1, 2, …, n.

6. The working range control method according to claim 1, wherein During the coordinated movement of the first telescopic arm and the second telescopic arm, the posture of the second telescopic arm is corrected; specifically: Taking the angle of the second telescopic arm as an independent variable, determining a functional relationship between the length and the angle of the second telescopic arm; Initial angle of the second telescopic arm β0 and the first set of angle data β1 The difference between them is Δβ01 , the angle corresponding to the current posture βi and the angle corresponding to the previous posture βi-1 The difference between them is Δβi , when | Δβi-Δβ01 | exceeds the set value, the downward deflection of the second telescopic arm causes errors; According to the obtained functional relationship, the corrected length of the second telescopic arm is Hi = f ( βi + Δβi ), and the angle is βi + Δβi 。 7. A working range control method according to claim 6, characterized in that The functional relationship between the length and angle of the second telescopic arm is shown in the following formula: ； In the formula, H i is the length of the second telescopic arm, i = 0, 1, 2, ……, n; β i is the angle between the second telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n.

8. The working range control method according to claim 1, characterized in that, The functional relationship between the first telescopic arm and the second telescopic arm is shown in the following formula: ； Wherein, L i is the length of the first telescopic arm, i = 0, 1, 2, ……, n; α i is the angle between the first telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n; H i is the length of the second telescopic arm, i = 0, 1, 2, ……, n; β i is the angle between the second telescopic arm and the horizontal reference plane, i = 0, 1, 2, ……, n; y i is the height of the workbench from the ground.

9. A system for implementing the working range control method according to any one of claims 1-8, characterized in that, include: a first angle detection unit, configured to obtain an angle of the first telescopic arm; a second angle detection unit, configured to obtain an angle of the second telescopic arm; A first length detection unit, used to obtain the length of the first telescopic arm; A second length detection unit, used to obtain the length of the second telescopic arm; The control unit is used to extract the signals provided by all angle detection units and length detection units, and to control the working range of the boom-type aerial work platform through a pre-stored working range control method.

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