A method for multi-body dynamics analysis of an insulated lifting platform

Abstract

The application discloses an insulating lifting platform multi-body dynamics analysis method, and belongs to the technical field of aerial work equipment. The method firstly completes the structural design of an insulating lifting platform including a hoisting mechanism, a luffing mechanism, a rotating mechanism, a stand column telescopic mechanism, a walking mechanism and a safety protection device, and carries out strength checking; a geometric model is established through a dynamics analysis software, kinematic constraints, driving constraints and load constraints are added to form a physical model; a plane Cartesian generalized coordinate system is established to obtain a system generalized coordinate vector; a kinematic constraint equation set is established to solve velocity and acceleration equations through a differential method; a rigid body component variation motion equation is established based on Newton's theorem, and Lagrange multiplier theorem is used to combine each component generalized coordinate vector, a mass matrix and a generalized force vector to obtain a multi-body system motion equation. The application comprehensively analyzes the kinematic and dynamic characteristics of the platform under multiple working conditions, and provides theoretical support for structural optimization and safety evaluation.

Description

Technical Field

[0001] This invention belongs to the technical field of high-altitude work equipment, and more specifically relates to a multibody dynamics analysis method for an insulated lifting platform. Background Technology

[0002] With the acceleration of urbanization and the continuous advancement of infrastructure construction, aerial work platforms are increasingly widely used in fields such as power maintenance, communication maintenance, building construction, and municipal engineering. However, traditional aerial work platforms are mostly made of steel structures, which still present many technical bottlenecks and safety hazards in actual use.

[0003] First, when operating in special environments such as power plants and railways, metal structure platforms are prone to becoming conductors, posing a significant risk of electric shock and leakage, and seriously threatening the personal safety of workers. Second, traditional platforms have limited functionality, only capable of lifting and lowering, making it difficult to meet the needs of multi-condition and multi-angle operations such as hoisting, rotating, and luffing in high-altitude work, severely impacting work efficiency and applicability. Furthermore, existing platforms generally suffer from excessive weight, insufficient rigidity, and poor stability, making them prone to structural deformation or swaying when bearing heavy loads or switching between multiple working conditions, significantly affecting the safety and reliability of the equipment.

[0004] As the working height increases, the requirements for the overall dynamic characteristics, load distribution, and stress analysis of key components also increase. Simple static analysis can no longer meet the needs of refined design. Currently, research on aerial work platforms both domestically and internationally is gradually developing towards multibody dynamics analysis. By utilizing multibody system dynamics theory and simulation technology, the kinematic and dynamic characteristics of the platform under different working conditions can be comprehensively and systematically analyzed, and its response laws and safety limits under complex loads and multi-degree-of-freedom coupling can be predicted. This provides strong support for the platform's structural optimization, control system design, and improvement of safety protection measures.

[0005] Therefore, developing a structural design for a multi-functional insulated lifting platform and systematically analyzing its stress and motion performance using multibody dynamics is a key technical approach to improve the technical level of aerial work equipment, ensure the safety of workers, and meet the diverse needs of modern construction sites. Summary of the Invention

[0006] The technical problem this invention aims to solve is to address the shortcomings of existing aerial work platforms, such as poor insulation performance, limited functionality, insufficient structural rigidity, poor stability, and lack of systematic dynamic analysis methods. This invention provides a multi-body dynamic analysis method and system for insulated lifting platforms. By establishing a multi-body dynamic model including multiple subsystems such as the lifting mechanism, luffing mechanism, rotating mechanism, and column telescopic mechanism, it enables accurate analysis and prediction of the platform's kinematic characteristics, load distribution, stress state of key components, and structural stability under different working conditions. This provides theoretical basis and technical support for the structural optimization design, safety performance evaluation, and control strategy formulation of multi-functional insulated lifting platforms, ultimately achieving safe and reliable operation of aerial work equipment in special environments such as those with power outages.

[0007] To achieve the above objectives, the present invention employs the following technical solution: the method comprising:

[0008] The structural design of the insulated lifting platform includes: a hoisting mechanism, a luffing mechanism, a rotating mechanism, a column telescopic mechanism, a traveling mechanism, and safety protection devices. The main structural dimensions and strength of each mechanism are calculated and necessary checks are performed to complete the structural design of the entire machine.

[0009] Establish a geometric model of the insulated lifting platform, either by constructing it using the geometric modeling module of dynamic analysis software or by importing it from other modeling software;

[0010] Kinematic constraints, driving constraints, and load constraints are added to the geometric model to form a physical model that reflects the mechanical properties of the system.

[0011] Establish a planar Cartesian generalized coordinate system, select the global coordinates of the origin of the component's body coordinate system and the rotation angle of the body coordinate system relative to the global coordinate system to form the component's Cartesian generalized coordinate vector, and obtain the system's generalized coordinate vector;

[0012] Establish a system of kinematic constraint equations;

[0013] By using the chain rule of differentiation, the velocity equation and acceleration equation are obtained respectively.

[0014] Establish the variational equations of motion for the rigid body components;

[0015] By combining the generalized coordinate vectors, mass matrix, and generalized force vectors of all components, the equations of motion for the multibody system are obtained.

[0016] The motion equations of the multibody system were solved using computer numerical methods to obtain the dynamic characteristics of the insulated lifting platform.

[0017] In one approach, when establishing the variational equation of motion for a rigid body component, the variational equation of motion for a free object is derived based on Newton's theorem. The origin of the rigid body coordinate system is located at the center of mass of the rigid body. All external forces are simplified to the center of mass using the equivalent substitution method and transformed into external force vectors and torques. The physical parameters of the rigid body component, including its mass, polar moment of inertia, external force vectors, and torques, are taken into account.

[0018] In one approach, the Lagrange multiplier theorem is used to derive the constraint-based dynamic equations of a multibody system. The generalized coordinate vectors, mass matrices, and generalized force vectors of all components in the mechanical system are combined to form a complete multibody system motion equation, which is used to describe the interaction between the components of the insulated lifting platform and the overall dynamic behavior of the system.

[0019] In one approach, when the system includes a flexible body, the dynamics of a multi-rigid-body system is extended. The flexible body is processed using a segmentation method, employing discretization, shape function, modal analysis, or finite element method. The flexible body and the multi-rigid-body system are then studied together to form a rigid-flexible coupled multi-body system. This yields the dynamic equations of a strongly coupled and strongly nonlinear system, which are then solved using computer numerical processing.

[0020] In one scheme, a global coordinate system and a connected coordinate system for each component are established. The global coordinates of the origin of the connected coordinate system of the component and the rotation angle of the connected coordinate system relative to the global coordinate system are selected to form a generalized coordinate vector. The number of generalized coordinates of the system is equal to three times the number of rigid components, forming a coordinate system that can completely describe the spatial position and attitude of the insulated lifting platform.

[0021] In one scheme, the established kinematic constraint equations are nonlinear equations of generalized coordinates, which constitute the position equations of the system. The number of constraint equations of the kinematic pairs determines the number of degrees of freedom of the system. The kinematic relationships and position constraints between the components of the insulated lifting platform are described by all the constraints applied to the system.

[0022] In one embodiment, the luffing mechanism drives the suspended load to move back and forth along the crossbeam to adjust the working radius. An electric motor drives a worm gear mechanism through a reducer. The two rotating shafts are connected by a coupling and a compensating shaft, and the drum device moves back and forth through gear transmission.

[0023] The rotating mechanism drives the hanger to rotate 360 ​​degrees. The lifting lugs are welded to the rotating chassis, and the rotating shaft is fixed to the chassis by bolts. The motor drives the worm gear to rotate through the reducer, so as to realize the rotation of the chassis relative to the worm wheel.

[0024] The column telescopic mechanism adopts a screw and nut transmission method. Each telescopic arm is composed of four separate right-angle columns welded together with equilateral angle steel. The telescopic arms are connected by screws and nuts. The rotation of the motor is converted into the linear motion of the screw and nut, which drives the sliding motion of the slider and the column.

[0025] Beneficial effects of this invention:

[0026] First, by establishing a complete multibody dynamics analysis model, this invention can accurately simulate the dynamic response characteristics of an insulated lifting platform under various working conditions such as lifting, luffing, rotation, and telescoping. It can comprehensively grasp the stress state and load distribution law of each key component, providing a scientific basis for the structural design and optimization of the platform, and effectively solving the technical problem that traditional static analysis methods cannot accurately predict the dynamic performance of structures under complex working conditions.

[0027] Secondly, the analysis method of the present invention takes into account the coupling effect and mutual influence between multiple motion mechanisms, and can identify weak links and potential safety hazards in the structural design. Through simulation analysis, risk factors that may lead to structural instability, overload or resonance can be predicted and eliminated in the design stage, which significantly improves the safety and reliability of the equipment and reduces the trial and error cost and cycle of product development.

[0028] Third, through systematic dynamic analysis, this invention can optimize the motion parameters, driving methods, and control strategies of each mechanism, thereby achieving stable and efficient platform operation, reducing energy loss and mechanical wear, and extending equipment service life. At the same time, it provides theoretical support for multi-functional integrated design, enabling a single device to meet various operational needs and improving the applicability and economic benefits of the equipment. Attached Figure Description

[0029] Figure 1 This is a flowchart of the method of the present invention;

[0030] Figure 2 For plane Cartesian generalized coordinates. Detailed Implementation

[0031] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Typical embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0032] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. To facilitate understanding, the invention will now be described more fully with reference to the accompanying drawings. Typical embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the invention more thorough and complete.

[0033] like Figure 1 As shown, a multibody dynamics analysis method for an insulated lifting platform specifically includes:

[0034] Step 1: Insulated Lifting Platform Structural Design

[0035] The device mainly consists of a lifting mechanism, a luffing mechanism, a slewing mechanism, a column telescopic mechanism, a traveling mechanism, and safety protection devices. Based on the overall scheme analysis, detailed designs were carried out for each mechanical mechanism. By applying theoretical mechanics, mechanics of materials, and related knowledge, the main structural dimensions and strengths of each mechanism were calculated and necessary checks were performed, thus completing the structural design of the entire machine. An important principle to follow in the structural design is light weight, high rigidity, and good stability.

[0036] The main structure and working principle of the multi-functional aerial work platform are as follows: After assembling the support frame and ensuring the entire chassis is level, adjust the clamping device to secure it to the supporting pillars. Once all drive devices are powered on, the hoisting mechanism's motor drives the telescopic boom to a certain position via a screw and nut transmission. The rotating mechanism's motor drives the hoist frame to rotate to the working position via a worm gear mechanism. The crossbeam adopts a double crossbeam structure made of H-beam steel. With guardrails and anti-slip insulating plates installed, it can be used as a maintenance platform. After removing the guardrails and anti-slip insulating plates, it can be used as a crane. The luffing mechanism's motor drives two drums to move back and forth along the crossbeam simultaneously. Upon contact with the limit switch at the crossbeam, rotation stops. The hoisting mechanism's motor simultaneously drives both drums to rotate, allowing the wire rope wound on the drums to vertically lower heavy objects.

[0037] 1) Lifting mechanism

[0038] The lifting mechanism is the most important lifting device in hoisting operations. It can not only operate independently, but also serve as the main starting device on other cranes, and therefore has been widely used.

[0039] The lifting mechanism can be driven by a 220V AC motor, with a working level of A3. There are four lifting points on the object being lifted. While ensuring that the two hooks lift synchronously, it is also necessary to prevent the danger of the heavy object pulling the drum in reverse due to a sudden power outage during the lifting process. Therefore, the lifting device must have a self-locking mechanism. Taking all factors into consideration, a mechanical self-locking mechanism with a worm gear mechanism is adopted, which has a simple structure and good self-locking effect.

[0040] The lifting mechanism mainly consists of a motor, reduction gears, worm gears, compensating shaft, drum, and support frame. Two worm gears are mounted at one end of the drum shaft, and the two worm shafts are connected together via a coupling and compensating shaft. A spur gear is connected to the inside of one worm shaft via a keyway. The motor transmits the rotational speed of the spur gear on the worm through the gear reduction mechanism, which in turn causes the drum shaft to rotate synchronously. The wire rope wound on the drum rotates accordingly, thus safely and smoothly lifting the heavy object vertically.

[0041] 2) Amplitude Variable Mechanism

[0042] The luffing mechanism primarily drives the suspended load to move back and forth along the crossbeam, thereby adjusting the working radius, significantly improving work efficiency, and ensuring the safety and stability of the lifting process. This luffing mechanism requires a stroke of 600mm. The double-arm crossbeam is made of hot-rolled H-beams. The two drum units must move synchronously along the crossbeam and be self-locking to prevent the drum units from swinging back and forth during lifting, causing the load to sway. A worm gear self-locking mechanism is employed. An electric motor drives the worm gear mechanism through a reducer. The two rotating shafts are connected together via a coupling and a compensating shaft. The worm gear is keyed to the inner side of one rotating shaft, and gears are mounted on the outer sides of the two rotating shafts. Gear transmission compensates for the center distance between the rotating shaft and the traveling gear. This allows the rotation of the worm gear to be simultaneously transmitted to the rotation of the traveling gears on both sides, thus driving the drum units to move smoothly back and forth.

[0043] 3) Rotating mechanism

[0044] The slewing mechanism is the key component for the crane to perform rotational motion, and it mainly consists of two parts:

[0045] (1) A drive transmission system that generates and transmits power.

[0046] (2) Supports the weight of the rotating part, prevents the rotating part from overturning, and connects the rotating part to the non-rotating part. The rotating mechanism drives the hanger to rotate 360°, avoiding dead angle positions, and realizing maintenance and lifting of heavy objects over a larger range. There are two main types of rotation drive: one is that the device above the traveling chassis achieves overall rotation, which is convenient for operation, maintenance, and has good stability; the other is that the hanger part achieves 360° rotation, mainly because the bearing load is small, the stability is good, and the installation is convenient. The slewing bearing device is divided into two main categories: turntable type and column type. The column type slewing bearing device can be divided into two types: rotating column type slewing bearing device and fixed column type slewing bearing device. The hanger part can be rotated while the part below the column is fixed. The worm gear transmission method is adopted, which can have a self-locking function at any position, meet the lifting and maintenance needs of different ranges, and reduce the redundancy of the mechanism. The lifting lug is welded to the rotating chassis, the rotating shaft is fixed to the chassis by bolts, the support flange is fixed to the column by welding, and the worm gear is fixed to the flange by bolts. The electric motor drives the worm gear to rotate through the reducer, which in turn drives the chassis to rotate 360° relative to the worm wheel, satisfying lifting and maintenance needs in different ranges.

[0047] 4) Column telescopic mechanism

[0048] The telescopic boom mechanism is the most important load-bearing component of this device, primarily responsible for raising and lowering the worktable to the designated position for operation. Since the lifting height of this equipment is 4 meters, the appropriate telescopic method has a significant impact on the overall performance of the equipment. Furthermore, the retracted size of this equipment is small, so the telescopic boom consists of three sections. The drive methods for the telescopic boom mechanism mainly include wire rope, rack and pinion, multi-stage telescopic cylinder, and screw-nut types. The wire rope drive method can use a double drum, with two separate wire ropes pulling the boom upwards, relying on the boom's own weight to retract. It has advantages such as simple structure, convenient installation, and low cost, but its stability is poor, it sways significantly, and it is prone to boom jamming. The rack and pinion type is widely used, but it is difficult to manufacture, has slightly lower stability, and a larger overall structure. The multi-stage telescopic cylinder type offers good stability, rigidity, and self-locking performance, but it is expensive and heavy. The screw-nut type mainly utilizes a screw and nut to achieve the transmission requirements. It primarily converts the rotary motion of the screw into the linear motion of the column, simultaneously transmitting motion and power. It generally operates intermittently, with short working times and low speeds. It boasts low manufacturing costs, good stability, light weight, and self-locking capability, but requires high installation precision. Considering all factors, a screw-nut drive system is adopted, primarily employing the principle of load sharing. When lifting heavy objects, the entire tensile force is borne by the screw, while the bending moment and torque are mainly borne by the column, with the clamping hoop also bearing a portion of the torque. Each telescopic boom section consists of four individual right-angled columns welded together with equilateral angle steel, connected by a screw-nut. The rotation of the motor is converted into the linear motion of the screw-nut, thereby driving the sliding motion of the slider and column.

[0049] Step 2: Multibody Dynamics Analysis of the Insulated Lifting Platform

[0050] Virtual prototyping technology, also known as dynamic simulation technology for mechanical systems, primarily encompasses two research areas: kinematics and dynamics analysis of mechanical systems. The core theory of virtual prototyping technology is multibody system dynamics, and the core issues in multibody system dynamics are modeling and solving. Physical modeling and mathematical modeling are crucial components of modeling. Physical modeling builds upon geometric models, while mathematical modeling is derived from physical models. Geometric models can be constructed using the geometric modeling module in dynamics analysis software or imported from other modeling software. Kinematic constraints, driving constraints, load constraints, and other physical model elements are then added to the geometric model to form a physical model that reflects the mechanical characteristics of the system. Multibody system dynamics mainly elucidates the solution methods for the dynamics problems of multibody systems. Each rigid body has certain motions or displacements, forming the kinematic and dynamic relationships of a relatively complex system. A mathematical model capable of solving the system using computer programs is then established to seek an optimal numerical solution method. Flexible body system dynamics is primarily an extension of multi-rigid body system dynamics. Its main characteristic lies in the use of segmentation methods in multi-rigid body system dynamics research, treating the flexible bodies in different ways. The main methods for solving mechanical system problems include: discretization, shape function methods, modal analysis, and finite element methods. By integrating the flexible body and multi-rigid body systems for study, the dynamic equations of the system are ultimately obtained. Because the dynamic equations of multi-flexible body systems are strongly coupled and strongly nonlinear, the solution method is quite complex and can only be achieved through computer numerical processing. If the model contains both multi-rigid body components and multi-flexible body systems, then the system is a rigid-flexible coupled multi-body system, which is the most general model of multi-body systems.

[0051] If a multibody system is subject to multiple constraints, its dynamic equations are derived by first obtaining the variational equations of motion of the free body using Newton's theorem, and then using the Lagrange multiplier theorem to derive the constraint-based dynamic equations of the multibody system.

[0052] 1) Velocity and acceleration of a free object

[0053] Suppose a planar mechanism is composed of It consists of several rigid components. A global coordinate system is established. The body coordinate system of each component i on the object Select the origin of the coordinate system of component i. global coordinates The rotation angle of the body coordinate system relative to the global coordinate system Cartesian generalized coordinate vector of component i ,like Figure 2As shown. The number of generalized coordinates of the system is obtained as k = 3n, and the generalized coordinate vector is... .

[0054] Let d be the number of constraint equations representing the kinematic pairs. Then, the set of kinematic constraint equations expressed in terms of the system's generalized coordinate vectors is:

[0055]

[0056] All constraints applied to the system:

[0057]

[0058] in, The system's position equations are composed of d nonlinear equations with k generalized coordinates.

[0059] Using the chain rule of differentiation, the equations for velocity and acceleration are derived respectively:

[0060]

[0061] 2) Variational equations of motion for a free object

[0062] Let i be a rigid body with mass m, and define the origin of the rigid body coordinate system. The origin Located at the center of mass of a rigid body, with polar moment of inertia of... The equivalent substitution method simplifies all external forces to the center of mass, transforming them into external force vectors. and torque Then the variational equation of motion of the rigid body at the coordinates of its center of mass is:

[0063]

[0064] In the formula, The origin of the connected coordinate system is fixed at the center of mass of the rigid body. Algebraic vectors; This represents the rotation angle of the connected coordinate system relative to the global coordinate system.

[0065] 3) Equations of motion for constrained multibody systems

[0066] The mechanical system consists of n interacting components, and the resulting system's variable differential equation of motion is:

[0067]

[0068] If we combine the generalized coordinate vectors, mass matrix, and generalized force vectors of all components, we finally obtain the equations of motion for the multibody system:

[0069] .

[0070] Step 3: Simulation Experiment Analysis

[0071] Simulation Experiment Process

[0072] 1. Establish a geometric model

[0073] • Use CAD modeling software (such as SolidWorks, CATIA, etc.) to construct a three-dimensional geometric model of the insulated lifting platform.

[0074] Import the model into multibody dynamics analysis software (such as ADAMS, RecurDyn, etc.).

[0075] 2. Add physical properties

[0076] Define the material properties of each component (such as density, elastic modulus, Poisson's ratio, etc.).

[0077] Set the mass and moment of inertia of each component.

[0078] Mark the centroid of each component and the coordinate system of the connected components based on the geometric model.

[0079] 3. Constraint and Connection Definitions

[0080] Add kinematic pairs (such as hinge pairs, prismatic pairs, etc.) to reflect the actual connection relationship.

[0081] Define the drive constraints of the platform's actuating mechanisms (such as hydraulic cylinders, drive motors, etc.).

[0082] Set appropriate load constraints (such as operational load, wind load, gravity, etc.).

[0083] 4. Define simulation conditions

[0084] The operating conditions are set according to the actual working scenario, such as: maximum rated load condition, platform lifting condition, extreme wind load, etc.

[0085] Set the simulation time, integration step size, and simulation accuracy requirements.

[0086] 5. Dynamic Simulation Analysis

[0087] Perform dynamic simulation to obtain the kinematic parameters (displacement, velocity, acceleration) and dynamic parameters (force, reaction force, stress, etc.) of each component.

[0088] Data collection and analysis are conducted for key components (such as the platform end, outriggers, and lifting arm).

[0089] 6. Results Processing and Validation

[0090] Compare the running trajectories and motion parameters of key components using curves.

[0091] Verify the rationality of the simulation results by comparing them with theoretical calculations or actual test results.

[0092] Modal analysis was used to verify the stability and dynamic response of the overall platform structure.

[0093] Table 1 Simulation Data Table

[0094]

[0095] Simulation Result Analysis

[0096] Displacement and velocity analysis shows that the maximum displacement of the lifting platform can reach 85 mm, and the maximum speed is within 55 mm / s, meeting the requirements for stable lifting. The smaller maximum displacement of the outriggers indicates that the platform has good horizontal stability during lifting.

[0097] Stress and acceleration analysis showed that the stress on all major components did not exceed the allowable range of their materials. The lifting arm and hydraulic cylinder experienced greater stress, requiring close monitoring of their fatigue life. The maximum acceleration occurred in the hydraulic cylinder, at 190 mm / s², and the structural stiffness of the equipment met the design standards.

[0098] Modal and stability verification: Modal analysis showed that the natural frequency of the platform structure was higher than the main excitation frequency, indicating that there was no risk of resonance.

[0099] The safety margin analysis shows that the simulation results of all components have sufficient safety margins and meet the conditions for practical application.

[0100] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0101] It should be understood that the above detailed description of the technical solutions of the present invention with reference to preferred embodiments is illustrative and not restrictive. Those skilled in the art can modify the technical solutions described in the embodiments or make equivalent substitutions for some of the technical features based on reading this specification; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multibody dynamics analysis method for an insulated lifting platform, characterized in that: The method includes: The structural design of the insulated lifting platform includes: a hoisting mechanism, a luffing mechanism, a rotating mechanism, a column telescopic mechanism, a traveling mechanism, and safety protection devices. The main structural dimensions and strength of each mechanism are calculated and necessary checks are performed to complete the structural design of the entire machine. Establish a geometric model of the insulated lifting platform, either by constructing it using the geometric modeling module of dynamic analysis software or by importing it from other modeling software; By adding kinematic constraints, driving constraints, and load constraints to the geometric model, a physical model that reflects the mechanical properties of the system is formed. Establish a planar Cartesian generalized coordinate system, select the global coordinates of the origin of the component's body coordinate system and the rotation angle of the body coordinate system relative to the global coordinate system to form the component's Cartesian generalized coordinate vector, and obtain the system's generalized coordinate vector; Establish a system of kinematic constraint equations; By using the chain rule of differentiation, the velocity equation and acceleration equation are obtained respectively. Establish the variational equations of motion for the rigid body components; By combining the generalized coordinate vectors, mass matrix, and generalized force vectors of all components, the equations of motion for the multibody system are obtained. The motion equations of the multibody system were solved using computer numerical methods to obtain the dynamic characteristics of the insulated lifting platform.

2. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: When establishing the variational equation of motion for the rigid body component, the variational equation of motion for the free object is obtained based on Newton's theorem. The origin of the rigid body coordinate system is located at the center of mass of the rigid body. All external forces are simplified to the center of mass through the equivalent substitution method and transformed into external force vectors and torques. The physical parameters of the rigid body component, such as mass, polar moment of inertia, external force vectors, and torques, are considered.

3. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: The Lagrange multiplier theorem is used to derive the constraint-based dynamic equations of a multibody system. The generalized coordinate vectors, mass matrices, and generalized force vectors of all components in the mechanical system are combined to form a complete multibody system motion equation, which is used to describe the interaction between the components of the insulated lifting platform and the overall dynamic behavior of the system.

4. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: When the system includes flexible bodies, the dynamics of multi-rigid-body systems is extended by using a segmentation method to process the flexible bodies using discretization, shape function, modal analysis, or finite element methods. The flexible bodies and multi-rigid-body systems are then studied together to form a rigid-flexible coupled multi-body system. This yields the dynamic equations of a strongly coupled and strongly nonlinear system, which are then solved using computer numerical processing.

5. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: Establish a global coordinate system and a connected coordinate system for each component. Select the global coordinates of the origin of the connected coordinate system of the component and the rotation angle of the connected coordinate system relative to the global coordinate system to form a generalized coordinate vector. The number of generalized coordinates of the system is equal to three times the number of rigid components, forming a coordinate system that can completely describe the spatial position and attitude of the insulated lifting platform.

6. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: The established set of kinematic constraint equations is a nonlinear set of equations for generalized coordinates, which constitutes the position equations of the system. The number of constraint equations for the kinematic pairs determines the number of degrees of freedom of the system. The kinematic relationships and positional constraints between the components of the insulated lifting platform are described by all the constraints applied to the system.

7. The multibody dynamics analysis method for an insulated lifting platform according to claim 1, characterized in that: The luffing mechanism drives the suspended load to move back and forth along the crossbeam to adjust the working radius. An electric motor drives a worm gear mechanism through a reducer. The two rotating shafts are connected by a coupling and a compensating shaft. The drum device moves back and forth through gear transmission. The rotating mechanism drives the hanger to rotate 360 ​​degrees. The lifting lugs are welded to the rotating chassis, and the rotating shaft is fixed to the chassis by bolts. The motor drives the worm gear to rotate through the reducer, so as to realize the rotation of the chassis relative to the worm wheel. The column telescopic mechanism adopts a screw and nut transmission method. Each telescopic arm is composed of four separate right-angle columns welded together with equilateral angle steel. The telescopic arms are connected by screws and nuts. The rotation of the motor is converted into the linear motion of the screw and nut, which drives the sliding motion of the slider and the column.

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