A method and system for analyzing continuous motion process of freight ropeway load

Abstract

The present invention provides a method for analyzing the continuous motion process of a freight ropeway load, comprising: obtaining the parameters of the load-bearing cable nodes and the load nodes of the freight ropeway; bringing the parameters of the load-bearing cable nodes and the load nodes of the freight ropeway into the pre-established load-bearing cable node and load node motion equations, increasing the time step according to the set time increment step, solving the node motion equations, calculating the position vector and the combined force of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, obtaining the position vector and the combined force of the load-bearing cable nodes and the load nodes in each time step; verifying the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vector and the combined force of the load-bearing cable nodes and the load nodes in each time step. The technical solution provided by the present invention inserts the load node into the load-bearing cable unit for calculation, and can obtain accurate calculation results when the number of units is small, reducing the calculation complexity and improving the calculation efficiency.

Description

Technical Field

[0001] The invention relates to the field of numerical calculation in the structural design and analysis of a freight ropeway, and in particular to a method and system for analyzing the continuous motion process of a freight ropeway load. Background Art

[0002] Overhead freight ropeway has the advantages of easy route selection, excellent transportation performance, strong applicability, high efficiency, and little impact from weather and external environment. It is widely used in forestry, construction, mining hydrology, tourism and other industries. The advantages of ropeway such as economy, energy saving, high efficiency and slight impact on the environment are unmatched by other means of transportation.

[0003] Freight ropeway mainly consists of working ropes, including load-bearing ropes and traction ropes, brackets, running trolleys, traction machines and other components. The load-bearing rope in the working rope is the main component of the freight ropeway. It is connected to both ends of the bracket and supports the entire load of the ropeway (running trolleys and loaded goods). It bears huge tension, so the load-bearing rope is required to have high tensile strength and the ability to resist impact and lateral pressure. The traction rope in the working rope is used to pull the running trolley along the load-bearing rope. The traction rope is a closed rope, which circulates in the ropeway along the bracket, pulley and traction machine when working.

[0004] When the cableway is running, the traction machine drum arranged on the starting side rolls, pulling the traction rope, and the traction weight moves continuously from the starting end of the cableway along the load-bearing rope until it reaches the end bracket and stops.

[0005] Among the existing cable dynamic calculation methods, the finite element method has been used to analyze the movement of a single or multiple loads at a given speed. However, most methods treat the moving load as a concentrated force without considering the inertial effect of the load mass in motion. In addition, in order to meet the calculation accuracy, the existing finite element analysis method needs to divide more units, resulting in low calculation efficiency. At the same time, it is easy to produce violent numerical oscillations when the load passes through the unit node. Summary of the invention

[0006] In order to solve the above problems and shortcomings, the present invention proposes a method and system for analyzing the continuous motion process of freight ropeway load. By establishing and solving the motion equations of the load-bearing cable nodes and the load nodes, the stress conditions of components such as the bracket, the load-bearing cable and the traction cable of the freight ropeway under the load impact are calculated, providing more accurate calculation results and reasonable safety factors for ropeway design and component selection.

[0007] The present invention is achieved by adopting the following technical solutions:

[0008] A method for analyzing the continuous motion process of a freight ropeway load, the improvement of which comprises:

[0009] Obtaining the parameters of the freight cableway's load-bearing cable nodes and load nodes;

[0010] Substitute the parameters of the load-bearing cable nodes and the load nodes of the freight cableway into the pre-established motion equations of the load-bearing cable nodes and the load nodes, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable nodes and the load nodes in each time step;

[0011] Verify the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vectors and the combined forces of the load-bearing rope nodes and the load nodes obtained at each time step;

[0012] The node motion equation is constructed based on the parameters of the freight cableway load-bearing cable nodes and the load nodes using the central difference method.

[0013] Preferably, the parameters of the load-bearing cable nodes and the load nodes of the freight cableway are brought into the pre-established node motion equation, the time step is increased according to the set time increment step, the node motion equation is solved, and the load-bearing cable nodes and the load position vector and the resultant force of the next time step are calculated until the preset time period ends, and the position vector and the resultant force of the load-bearing cable nodes and the load nodes of each time step are obtained, including:

[0014] Solving the node motion equation at the current time step to obtain the position vectors of the load-bearing cable node and the load node at the next time step;

[0015] Calculate the resultant force of the load-bearing cable node and the load node at the next time step according to the position vectors of the load-bearing cable node and the load node at the next time step;

[0016] The time step is increased according to the set time increment step until the preset time period ends, and the combined force and position vector of the load-bearing cable node and the load node at each time step within the preset time period are obtained.

[0017] Preferably, the motion equations of the load-bearing cable nodes and the load nodes are as follows:

[0018]

[0019] Where: m: the mass of the cable node and the load node, Acceleration of the cable node and the load node; F n : The resultant force of the cable node and the load node at the nth time step; f dmp : Virtual damping force.

[0020] Wherein, the virtual damping force is calculated as follows:

[0021]

[0022] Where, ζ: damping factor, ζ>0; The speed of the node.

[0023] Preferably, when the freight cableway node is a load-bearing cable node, the resultant force F acting on the load-bearing cable node at the nth time step is n Calculate as follows:

[0024] F n =G i +f i n

[0025] In the formula, G i : Gravity acting on the node i of the load-bearing cable, f i n : The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step;

[0026] When the freight cableway node is a load node, the resultant force F acting on the load node at the nth time step n Calculate as follows:

[0027]

[0028] In the formula, G p : Load gravity, The resultant force of the internal forces of the load-bearing cable unit at the nth time step; is the virtual traction applied to the load at the nth time step; p: is the load node of the i-th unit of the load-bearing cable at the nth time step, between the load-bearing cable node i and the node i+1.

[0029] Preferably, the resultant internal force f of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step is i n Calculate as follows:

[0030]

[0031] In the formula, The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i+1 at the nth time step; f i n : The internal force value of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step; The direction vector of the load-bearing cable element i at time t;

[0032] Where: The internal force value f of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step i n Calculate as follows:

[0033]

[0034] In the formula, The length of cable node i at the nth time step; The length of the load-bearing cable node i in the initial state; EA l : The product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus;

[0035] in,

[0036]

[0037]

[0038] In the formula, The initial position vector of the load-bearing cable node i, The initial position vector of the load-bearing cable node i+1; The position vector of cable node i at the nth time step; The position vector of cable node i+1 at the nth time step.

[0039] Preferably, the resultant force of the internal force of the load-bearing cable unit at the nth time step load is Calculate as follows:

[0040]

[0041] In the formula, The force exerted by the load cable unit at the load node p in the nth time step on it in the direction from node p to i; The force exerted by the load cable unit at the load node p in the nth time step on the load node p in the direction from node p to i+1;

[0042] in,

[0043]

[0044]

[0045]

[0046]

[0047] In the formula, The position vector of cable node i at the nth time step, The position vector of the load node p at the nth time step; The position vector of cable node i+1 at the nth time step;

[0048] The virtual traction force on the load Calculate as per the formal:

[0049]

[0050] In the formula, Unit vector of the traction force direction.

[0051] Preferably, the time increment step is calculated as follows:

[0052]

[0053] Where, h: time increment step; is the original length of unit i; EA l : product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus; q l : unit gravity of the load-bearing cable; g: acceleration due to gravity.

[0054] Preferably, the acceleration of the load-bearing cable node or the load node Calculate as follows:

[0055]

[0056] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : The position vector of the load node or load node at the n-1th time step; h: The time increment step;

[0057] The speed of the load node or load node Calculate as follows:

[0058]

[0059] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n-1 : The position vector of the cable node or load node at the n-1th time step.

[0060] Preferably, when the load moves continuously, the node position vector of the node i of the load-bearing cable unit at the n+1th time step is Calculate as follows:

[0061]

[0062] In the formula, The position vector of cable node i at the n+1th time step; The position vector of cable node i at the nth time step; The position vector of cable node i in the n-1th time step; h: time increment step; m: i : The mass of the freight cableway load-bearing cable node i; F i n : The resultant force acting on the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i; The second dynamic damping correction factor of the load-bearing cable node i.

[0063] Among them, the first dynamic damping correction coefficient of the load-bearing cable node i is Calculate as follows:

[0064]

[0065] In the formula, The original length of the load-bearing cable element i; The length from the load cable node i to the load node p in the nth time step; ζ: damping factor, ζ>0;

[0066] The second dynamic damping correction coefficient of the load-bearing cable node i Calculate as follows:

[0067]

[0068] Preferably, when the load is in continuous motion, the node position vector x of the node i+1 of the load-bearing cable unit at the n+1th time step is n+1 Calculate as follows:

[0069]

[0070] In the formula, The position vector of cable node i+1 at the n+1th time step; The position vector of cable node i+1 at the nth time step; The position vector of the cable node i+1 in the n-1th time step; h: time increment step; m: i+1 : The mass of the freight cableway load-bearing cable node i; The resultant force acting at the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i+1; The second dynamic damping correction factor of the load-bearing cable node i+1;

[0071] Wherein: the first dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated according to the following formula:

[0072]

[0073] In the formula, The original length of the load-bearing cable element i; The length from the load node p to the load cable node i+1 in the nth time step;

[0074] The second dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated as follows:

[0075]

[0076] Preferably, the initial value of the motion equation of the load-bearing cable node or the load node of the load continuous motion is calculated as follows:

[0077]

[0078] In the formula, x 0 : initial position vector of the cable node or load node; x -1 : The position vector of the cable node or load node at the -1th time step; x 1 : The position vector of the cable node or load node in the first time step, x -1 =x 0 ; m: mass of the load node; F 0 : The resultant force acting on the node when the load node passes through the saddle.

[0079] Preferably, the step of calculating the load movement position when the freight ropeway load continuously moves comprises:

[0080] At the n+1th time increment, the position of the load node p is calculated as follows

[0081]

[0082] In the formula, The position of the load node p at the n+1th time increment; The position of the load node p in the nth time increment; Δx p : The load node movement position in each time increment h;

[0083] Where Δx p =V p h: The load node movement position within each time increment h is calculated as follows:

[0084] Δx p =V p ·h

[0085] Where V p : Moving speed of load node p; h: Time increment step.

[0086] Preferably, the freight ropeway parameters include: ropeway span, ropeway height difference, load-bearing rope unit gravity, load-bearing rope cross-sectional area multiplied by elastic modulus, traction rope unit gravity, traction rope cross-sectional area multiplied by elastic modulus and load mass.

[0087] A method and system for analyzing the continuous motion process of a freight ropeway load, comprising: an acquisition module, a calculation module and a verification module;

[0088] Acquisition module: to obtain the parameters of the freight cableway load-bearing cable nodes and load nodes;

[0089] Calculation module: bringing the parameters of the load-bearing cable nodes and the load nodes of the freight cableway into the pre-established motion equations of the load-bearing cable nodes and the load nodes, increasing the time step according to the set time increment step, solving the node motion equations, calculating the position vectors and the resultant forces of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, and obtaining the position vectors and the resultant forces of the load-bearing cable nodes and the load nodes in each time step;

[0090] Verification module: verifying the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vectors and the combined forces of the load-bearing cable nodes and the load nodes at each time step.

[0091] Compared with the closest existing technology, the technical solution provided by the present invention has the following beneficial effects:

[0092] The present invention provides a method and system for analyzing the continuous motion process of a freight ropeway load, which can realize the analysis of the continuous motion process from suspending a load on a load-bearing cable to the load starting from rest, and provides an effective theoretical basis and solution for selecting the dynamic safety factor of cableway load-bearing cables, brackets and other components.

[0093] The present invention provides a method and system for analyzing the continuous motion process of a freight cableway load, wherein the load is connected to a load-bearing cable node as an independent movable node, and the internal forces of the load-bearing cable units are equal, which conforms to the actual situation of rolling contact between the load-bearing cable and the load, and can avoid complex calculations such as the judgment of contact between objects, thereby improving the calculation accuracy and efficiency.

[0094] The present invention provides a method and system for analyzing the continuous motion process of a freight ropeway load, which introduces the effect of a virtual traction force exerted on the load into the calculation process, thereby improving the calculation accuracy.

[0095] The present invention provides a method and system for analyzing the continuous motion process of a freight ropeway load, which adopts a dynamic damping coefficient correction coefficient to reduce the vibration amplitude of the load-bearing cable nodes close to the load, avoid abnormal and violent oscillation when the load passes through the load-bearing cable nodes, and ensure the accuracy of the continuous process analysis.

[0096] The present invention provides a method and system for analyzing the continuous motion process of a freight ropeway load, which can freely set the load-bearing rope nodes according to calculation needs, and can obtain good calculation accuracy with fewer nodes, thereby greatly improving the analysis and calculation efficiency.

[0097] The present invention provides a method and system for analyzing the continuous motion process of a freight ropeway load. The selected time step is only related to the position of the load-bearing cable node and is not affected by the position and speed of the load node, thereby ensuring calculation stability and convergence. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] Figure 1 It is a schematic diagram of a method for analyzing the continuous motion process of a freight ropeway load according to the present invention;

[0099] Figure 2 It is a schematic diagram of the sections of the load-bearing ropes of the freight ropeway of the present invention;

[0100] Figure 3 It is a schematic diagram of the internal force of the unit node of the present invention;

[0101] Figure 4 It is a force diagram of the unit node where the load is located in the present invention;

[0102] Figure 5 It is a schematic diagram of the force of the load-bearing cable unit of the present invention;

[0103] Figure 6 It is a schematic diagram of the overall force of the load of the present invention;

[0104] Figure 7 It is a schematic diagram of a freight ropeway load continuous motion process analysis system of the present invention. DETAILED DESCRIPTION

[0105] In order to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0106] Embodiment 1

[0107] The present invention is achieved by adopting the following technical solutions:

[0108] A method for analyzing the continuous motion process of freight ropeway loads, such as Figure 1 As shown, the following steps are included:

[0109] Step 1: Obtain the parameters of the freight cableway load-bearing cable node and load node;

[0110] Step 2: Substitute the parameters of the load-bearing cable nodes and the load nodes of the freight cableway into the pre-established motion equations of the load-bearing cable nodes and the load nodes, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable nodes and the load nodes in each time step;

[0111] Step 3: Verify the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can withstand and the position vectors and combined forces of the load-bearing cable nodes and load nodes at each time step.

[0112] Step 1: Obtain the freight cableway parameters, including: cableway span, cableway height difference, unit gravity of the load-bearing cable, and the product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus.

[0113] Freight ropeway Figure 2 As shown, the span of the current gear of the rear saddle cableway is L, the height difference is h, and the load-bearing cable is divided into n units with a total of n+1 nodes.

[0114] Step 2: Substitute the parameters of the load-bearing cable nodes and the load nodes of the freight cableway into the pre-established motion equations of the load-bearing cable nodes and the load nodes, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable nodes and the load nodes in each time step;

[0115] Solving the node motion equation at the current time step to obtain the position vectors of the load-bearing cable node and the load node at the next time step;

[0116] Calculate the resultant force of the load-bearing cable node and the load node at the next time step according to the position vectors of the load-bearing cable node and the load node at the next time step;

[0117] The time step is increased according to the set time increment step until the preset time period ends, and the combined force and position vector of the load-bearing cable node and the load node at each time step within the preset time period are obtained.

[0118] Specifically, the motion equations of the load-bearing cable nodes and the load nodes are as follows:

[0119]

[0120] Where: m: the mass of the cable node or load node, The acceleration of the load node or the load node; F n : The resultant force acting on the cable node or load node at the nth time step; f dmp : Virtual damping force.

[0121] Wherein, the virtual damping force is calculated as follows:

[0122]

[0123] Where, ζ: damping factor, ζ>0; The speed of the node.

[0124] Each node of the load-bearing cable satisfies Newton's second law when in motion. When the freight cableway node is a load-bearing cable node, Figure 3 As shown, the resultant force F acting on the cable node at the nth time step is n Calculate as follows:

[0125] F n =G i +f i n

[0126] In the formula, G i : Gravity acting on the node i of the load-bearing cable, f i n : The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step.

[0127] The resultant internal force f of the load-bearing cable unit connected to node i at the nth time step i n Calculate as follows:

[0128]

[0129] In the formula, The resultant internal force of the cable unit on one side connected to the cable node i+1 at the nth time step. The forces on both sides of the cable node are the same in magnitude but opposite in direction; f i n : The internal force value of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step; The direction vector of the rod unit at the nth time step;

[0130] Where: The internal force value f of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step i n Calculate as follows:

[0131]

[0132] In the formula, The length of cable node i at the nth time step; The length of the load-bearing cable node i in the initial state; EA l : The product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus;

[0133] in,

[0134]

[0135]

[0136] In the formula, The initial position vector of the load-bearing cable node i, The initial position vector of the load-bearing cable node i+1; The position vector of cable node i at the nth time step; The position vector of cable node i+1 at the nth time step;

[0137] When the freight cableway node is a load node, the load contacted by the load-bearing cable can be regarded as an independent movable node, and the node mass is the load mass, which generates a force between it and the load-bearing cable node, such as Figure 4 As shown, the resultant force F acting on the load node at the nth time step is n Calculate as follows:

[0138]

[0139] In the formula, G p : Load gravity, The resultant force of the internal forces of the load-bearing cable unit at the nth time step; is the virtual traction on the load node at the nth time step; p: is the load node of the i-th unit of the load-bearing cable at the nth time step, between the load-bearing cable node i and the node i+1.

[0140] like Figure 5 As shown, the resultant force of the internal force of the load-bearing cable unit at the nth time step load is Calculate as follows:

[0141]

[0142] In the formula, The force exerted by the load cable unit where the load node p is located in the nth time step along the direction from the load node p to the load cable node i; The force exerted by the load-bearing cable unit at the load node p in the nth time step on its load in the direction from node p to the load-bearing cable node i+1;

[0143] in,

[0144]

[0145]

[0146]

[0147]

[0148] In the formula, The position vector of cable node i at the nth time step, The position vector of the load node p at the nth time step; The position vector of the cable node i+1 at the nth time step;

[0149] The load moves at a constant speed on the cableway. In each time increment, the traction force on the load is balanced with the deadweight of the load and the internal force of the load-bearing cable unit. Figure 6 As shown, the virtual traction force on the load Calculate as per the formal:

[0150]

[0151] In the formula, Unit vector of the traction force direction.

[0152] Specifically, the time increment step is calculated as follows:

[0153]

[0154] Where, h: time increment step; is the original length of unit i; EA l : product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus; q l : Unit gravity of the load-bearing cable.

[0155] Specifically, the acceleration of the load-bearing cable node or the load node Calculate as follows:

[0156]

[0157] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : The position vector of the load node or load node at the n-1th time step; h: time increment step; g: gravitational acceleration.

[0158] The speed of the load node or load node Calculate as follows:

[0159]

[0160] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n-1 : The position vector of the cable node or load node at the n-1th time step.

[0161] Specifically, the calculation of the node resultant force of the load when the freight ropeway load moves continuously includes: the force of the load node p exerted on the load node i when the load moves continuously and the force of the load node p exerted on the load node i+1 when the load moves continuously.

[0162] Specifically, when the load moves continuously, the node position vector x of the load cable node or the load node at the n+1th time step is n+1 Calculate as follows:

[0163]

[0164] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : the position vector of the load node or load node of the n-1th time step; h: the time increment step; m: the mass of the load node or load node of the freight cableway; F n : The resultant force acting on the node of the load-bearing cable node or the load node at the nth time step; c1: The first damping coefficient of the load-bearing cable node or the load node; c2: The second damping coefficient of the load-bearing cable node or the load node.

[0165] When the load moves continuously, a dynamic damping correction factor is introduced to improve the accuracy of the calculation.

[0166] Specifically, when the load moves continuously, the node position vector of the node i of the load-bearing cable unit at the n+1th time step is Calculate as follows:

[0167]

[0168] In the formula, The position vector of cable node i at the n+1th time step; The position vector of cable node i at the nth time step; The position vector of cable node i in the n-1th time step; h: time increment step; m: i : The mass of the freight cableway load-bearing cable node i; F in : The resultant force acting on the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i; The second dynamic damping correction factor of the load-bearing cable node i;

[0169] Among them, the first dynamic damping correction coefficient of the load-bearing cable node i is Calculate as follows:

[0170]

[0171] In the formula, The original length of the load-bearing cable element i; The length from node i to node p at the nth time step; ζ: damping factor, ζ>0;

[0172] The second dynamic damping correction coefficient of the load-bearing cable node i Calculate as follows:

[0173]

[0174] Specifically, when the load moves continuously,

[0175] The node position vector x of the node i+1 of the load-bearing cable element at the n+1th time step n+1 Calculate as follows:

[0176]

[0177] In the formula, The position vector of cable node i+1 at the n+1th time step; The position vector of cable node i+1 at the nth time step; The position vector of the cable node i+1 in the n-1th time step; h: time increment step; m: i+1 : The mass of the freight cableway load-bearing cable node i; The resultant force acting at the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i+1; The second dynamic damping correction factor of the load-bearing cable node i+1;

[0178] Wherein: the first dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated according to the following formula:

[0179]

[0180] In the formula, The original length of the load-bearing cable element i; The length from load node p to node i+1 in the nth time step;

[0181] The second dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated as follows:

[0182]

[0183] Specifically, the initial position vector of the node of the continuous motion of the load is calculated as follows:

[0184]

[0185] In the formula, x 0 : initial position vector of the cable node or load node; x -1 : The position vector of the node at the -1th time step; x 1 : The position vector of the first time step, x -1 =x 0 ; m: mass of the load node; F 0 : The resultant force when the load node passes through the saddle.

[0186] Specifically, the calculation of the load movement position when the freight ropeway load moves continuously includes:

[0187] At the n+1th time increment, the position of the load p is calculated as follows

[0188]

[0189] In the formula, The position of the load node p at the n+1th time increment; The position of the load node p in the nth time increment; Δx p : The load node movement position in each time increment h;

[0190] Where Δx p =V p h: The load movement position in each time increment h is calculated as follows:

[0191] Δx p =V p ·h

[0192] Where V p : Moving speed of load node p; h: Time increment step.

[0193] Embodiment 2

[0194] A freight ropeway load passing through the saddle impact dynamic calculation system, such as Figure 7 As shown, it includes: an acquisition module, a calculation module and a verification module;

[0195] Acquisition module: used to obtain the parameters of the freight cableway load-bearing cable nodes and load nodes;

[0196] Calculation module: used to bring the parameters of the freight cableway load-bearing cable node and the load node into the pre-established node motion equation, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the node in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of each time step;

[0197] Verification module: verifying the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vectors and the combined forces of the load-bearing cable nodes and the load nodes at each time step.

[0198] Specifically, in the calculation module, the parameters of the load-bearing cable nodes and the load nodes of the freight cableway are brought into the pre-established motion equations of the load-bearing cable nodes and the load nodes, the time step is increased according to the set time increment step, the node motion equation is solved, and the position vector and the resultant force of the load-bearing cable nodes and the load nodes in the next time step are calculated until the preset time period ends, and the position vector and the resultant force of the load-bearing cable nodes and the load nodes in each time step are obtained, including;

[0199] Solving the node motion equation at the current time step to obtain the position vectors of the load-bearing cable node and the load node at the next time step;

[0200] Calculate the resultant force of the load-bearing cable node and the load node at the next time step according to the position vectors of the load-bearing cable node and the load node at the next time step;

[0201] The time step is increased according to the set time increment step until the preset time period ends, and the combined force and position vector of the load-bearing cable node and the load node at each time step within the preset time period are obtained.

[0202] Specifically, the motion equations of the load-bearing cable nodes and the load nodes are as follows:

[0203]

[0204] Where: m: the mass of the cable node or load node, The acceleration of the load node or the load node; F n : The resultant force acting on the cable node or load node at the nth time step; f dmp : Virtual damping force.

[0205] Wherein, the virtual damping force is calculated as follows:

[0206]

[0207] Where, ζ: damping factor, ζ>0; The speed of the node.

[0208] Each node of the load-bearing cable satisfies Newton's second law when in motion. When the freight cableway node is a load-bearing cable node, Figure 3 As shown, the resultant force F acting on the cable node at the nth time step is n Calculate as follows:

[0209] F n =G i +f i n

[0210] In the formula, G i : Gravity acting on the node i of the load-bearing cable, f i n : The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step.

[0211] The resultant internal force f of the load-bearing cable unit connected to node i at the nth time step i n Calculate as follows:

[0212]

[0213] In the formula, The resultant internal force of the cable unit on one side connected to the cable node i+1 at the nth time step. The forces on both sides of the cable node are the same in magnitude but opposite in direction; f i n : The internal force value of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step; The direction vector of the rod unit at the nth time step;

[0214] Where: The internal force value f of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step i n Calculate as follows:

[0215]

[0216] In the formula, The length of cable node i at the nth time step; The length of the load-bearing cable node i in the initial state; EA l : The product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus;

[0217] in,

[0218]

[0219]

[0220] In the formula, The initial position vector of the load-bearing cable node i, The initial position vector of the load-bearing cable node i+1; The position vector of cable node i at the nth time step; The position vector of cable node i+1 at the nth time step;

[0221] When the freight cableway node is a load node, the load contacted by the load-bearing cable can be regarded as an independent movable node, and the node mass is the load mass, which generates a force between it and the load-bearing cable node, such as Figure 4 As shown, the node force F at the nth time step n Calculate as follows:

[0222]

[0223] In the formula, G p : Load gravity, The resultant force of the internal forces of the load-bearing cable unit at the nth time step; is the virtual traction on the load node at the nth time step; p: is the load node of the i-th unit of the load-bearing cable at the nth time step, between the load-bearing cable node i and the node i+1.

[0224] like Figure 5 As shown, the resultant force of the internal force of the load-bearing cable unit at the nth time step load is Calculate as follows:

[0225]

[0226] In the formula, The force exerted by the load cable unit where the load node p is located in the nth time step along the direction from the load node p to the load cable node i; The force exerted by the load-bearing cable unit at the load node p in the nth time step on its load in the direction from node p to the load-bearing cable node i+1;

[0227] in,

[0228]

[0229]

[0230]

[0231]

[0232] In the formula, The position vector of cable node i at the nth time step, The position vector of the load node p at the nth time step; The position vector of the cable node i+1 at the nth time step;

[0233] The load moves at a constant speed on the cableway. In each time increment, the traction force on the load is balanced with the deadweight of the load and the internal force of the load-bearing cable unit. Figure 6 As shown, the virtual traction force on the load Calculate as per the formal:

[0234]

[0235] In the formula, Unit vector of the traction force direction.

[0236] Specifically, the time increment step is calculated as follows:

[0237]

[0238] Where, h: time increment step; is the original length of unit i; EA l : product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus; q l : Unit gravity of the load-bearing cable.

[0239] Specifically, the acceleration of the load-bearing cable node or the load node Calculate as follows:

[0240]

[0241] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : The position vector of the load node or load node at the n-1th time step; h: time increment step; g: gravitational acceleration.

[0242] The speed of the load node or load node Calculate as follows:

[0243]

[0244] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n-1 : The position vector of the cable node or load node at the n-1th time step.

[0245] Specifically, the calculation of the node resultant force of the load when the freight ropeway load moves continuously includes: the force of the load node p exerted on the load node i when the load moves continuously and the force of the load node p exerted on the load node i+1 when the load moves continuously.

[0246] Specifically, when the load moves continuously, the node position vector x of the load cable node or the load node at the n+1th time step is n+1 Calculate as follows:

[0247]

[0248] In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : the position vector of the load node or load node of the n-1th time step; h: the time increment step; m: the mass of the load node or load node of the freight cableway; F n : The resultant force acting on the node of the load-bearing cable node or the load node at the nth time step; c1: The first damping coefficient of the load-bearing cable node or the load node; c2: The second damping coefficient of the load-bearing cable node or the load node.

[0249] When the load moves continuously, a dynamic damping correction factor is introduced to improve the accuracy of the calculation.

[0250] Specifically, when the load moves continuously, the node position vector of the node i of the load-bearing cable unit at the n+1th time step is Calculate as follows:

[0251]

[0252] In the formula, The position vector of cable node i at the n+1th time step; The position vector of cable node i at the nth time step; The position vector of cable node i in the n-1th time step; h: time increment step; m: i : The mass of the freight cableway load-bearing cable node i; F i n : The resultant force acting on the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i; The second dynamic damping correction factor of the load-bearing cable node i;

[0253] Among them, the first dynamic damping correction coefficient of the load-bearing cable node i is Calculate as follows:

[0254]

[0255] In the formula, The original length of the load-bearing cable element i; The length from node i to node p at the nth time step; ζ: damping factor, ζ>0;

[0256] The second dynamic damping correction coefficient of the load-bearing cable node i Calculate as follows:

[0257]

[0258] Specifically, when the load moves continuously,

[0259] The node position vector x of the node i+1 of the load-bearing cable element at the n+1th time step n+1 Calculate as follows:

[0260]

[0261] In the formula, The position vector of cable node i+1 at the n+1th time step; The position vector of cable node i+1 at the nth time step; The position vector of the cable node i+1 in the n-1th time step; h: time increment step; m: i+1 : The mass of the freight cableway load-bearing cable node i; The resultant force acting at the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i+1; The second dynamic damping correction factor of the load-bearing cable node i+1;

[0262] Wherein: the first dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated according to the following formula:

[0263]

[0264] In the formula, The original length of the load-bearing cable element i; The length from load node p to node i+1 in the nth time step;

[0265] The second dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated as follows:

[0266]

[0267] Specifically, the initial position vector of the node of the continuous motion of the load is calculated as follows:

[0268]

[0269] In the formula, x 0 : initial position vector of the cable node or load node; x -1 : The position vector of the node at the -1th time step; x 1 : The position vector of the first time step, x -1 =x 0 ; m: mass of the load node; F 0 : The resultant force acting on the node when the load node passes through the saddle.

[0270] Specifically, the calculation of the load movement position when the freight ropeway load moves continuously includes:

[0271] At the n+1th time increment, the position of the load p is calculated as follows

[0272]

[0273] In the formula, The position of the load node p at the n+1th time increment; The position of the load node p in the nth time increment; Δx p : The load node movement position in each time increment h;

[0274] Where Δx p =V p h: The load movement position in each time increment h is calculated as follows:

[0275] Δx p =V p ·h

[0276] Where V p : Moving speed of load node p; h: Time increment step.

[0277] Step 3: Verify the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can withstand and the position vectors and combined forces of the load-bearing cable nodes and load nodes at each time step.

[0278] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0279] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0280] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0281] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0282] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art can still modify or make equivalent substitutions to the specific implementations of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the scope of protection of the claims of the present invention to be approved.

Claims

1. A method for analyzing the continuous motion process of a freight ropeway load, characterized in that: include: Obtaining the parameters of the freight cableway's load-bearing cable nodes and load nodes; Substitute the parameters of the load-bearing cable nodes and the load nodes of the freight cableway into the pre-established motion equations of the load-bearing cable nodes and the load nodes, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the load-bearing cable nodes and the load nodes in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable nodes and the load nodes in each time step; Verify the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vectors and combined forces of the load-bearing rope nodes and the load nodes obtained at each time step; The node motion equation is constructed based on the parameters of the freight cableway load-bearing cable nodes and load nodes using the central difference method; The parameters of the freight cableway load-bearing cable node and the load node are brought into the pre-established node motion equation, and the time step is increased according to the set time increment step, the node motion equation is solved, and the load-bearing cable node and the load position vector and the resultant force of the next time step are calculated until the preset time period ends, and the position vector and the resultant force of the load-bearing cable node and the load node of each time step are obtained, including: Solving the node motion equation at the current time step to obtain the position vectors of the load-bearing cable node and the load node at the next time step; Calculate the resultant force of the load-bearing cable node and the load node at the next time step according to the position vectors of the load-bearing cable node and the load node at the next time step; Increase the time step according to the set time increment step until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable node and the load node at each time step in the preset time period; The motion equations of the cable nodes and load nodes are as follows: Where: m: the mass of the cable node or load node, The acceleration of the load node or the load node; F n : The resultant force acting on the cable node or load node at the nth time step; f dmp : virtual damping force; Wherein, the virtual damping force is calculated as follows: Where, ζ: damping factor, ζ>0; The speed of the node; When the freight cableway node is a load-bearing cable node, the resultant force F acting on the load-bearing cable node at the nth time step is n Calculate as follows: F n =G i +f i n In the formula, G i : Gravity acting on the load-bearing cable node i, f i n : The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step; When the freight cableway node is a load node, the resultant force F acting on the load node at the nth time step n Calculate as follows: In the formula, G p : Load gravity, The resultant force of the internal forces of the load-bearing cable unit at the nth time step; is the virtual traction on the load node at the nth time step; p: is the load node of the i-th unit of the load-bearing cable at the nth time step, between the load-bearing cable node i and the node i+1.

2. The method according to claim 1, characterized in that The resultant force f of the internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step i n Calculate as follows: In the formula, The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i+1 at the nth time step; f i n : The internal force value of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step; The direction vector of the load-bearing cable element i at time t; Where: The internal force value f of the load-bearing cable unit i connected to the load-bearing cable node i at the nth time step i n Calculate as follows: In the formula, The length of cable node i at the nth time step; The length of the load-bearing cable node i in the initial state; EA l : The product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus; in, In the formula, The initial position vector of the load-bearing cable node i, The initial position vector of the load-bearing cable node i+1; The position vector of cable node i at the nth time step; The position vector of cable node i+1 at the nth time step.

3. The method according to claim 2, characterized in that The resultant force of the internal forces of the load-bearing cable unit at the nth time step load Calculate as follows: In the formula, The force exerted by the load cable unit at the load node p in the nth time step on it in the direction from node p to i; The force exerted by the load cable unit at the load node p in the nth time step on the load node p in the direction from node p to i+1; in, In the formula, The position vector of cable node i at the nth time step, The position vector of the load node p at the nth time step; The position vector of cable node i+1 at the nth time step; The virtual traction force on the load Calculate as per the formal: In the formula, Unit vector of the traction force direction.

4. The method according to claim 1, characterized in that The time increment step is calculated as follows: Where, h: time increment step; is the original length of unit i; EA l : product of the cross-sectional area of ​​the load-bearing cable and the elastic modulus; q l : unit gravity of the load-bearing cable; g: acceleration due to gravity.

5. The method according to claim 1, characterized in that The acceleration of the load node or load node Calculate as follows: In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n : Position vector of the cable node or load node at the nth time step; x n-1 : The position vector of the load node or load node at the n-1th time step; h: The time increment step; The speed of the load node or load node Calculate as follows: In the formula, x n+1 : Position vector of the cable node or load node at the n+1th time step; x n-1 : The position vector of the cable node or load node at the n-1th time step.

6. The method according to claim 5, characterized in that When the load moves continuously, the node position vector of the node i of the load-bearing cable unit at the n+1th time step is Calculate as follows: In the formula, The position vector of cable node i at the n+1th time step; The position vector of cable node i at the nth time step; The position vector of cable node i at the n-1th time step; h: time increment step; m i : The mass of the freight cableway load-bearing cable node i; F i n : The resultant force acting on the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i; The second dynamic damping correction factor of the load-bearing cable node i; Among them, the first dynamic damping correction coefficient of the load-bearing cable node i is Calculate as follows: In the formula, The original length of the load-bearing cable element i; The length from the load cable node i to the load node p in the nth time step; ζ: damping factor, ζ>0; The second dynamic damping correction coefficient of the load-bearing cable node i Calculate as follows:

7. The method according to claim 6, characterized in that When the load is in continuous motion, the node position vector x of the node i+1 of the load-bearing cable unit at the n+1th time step is n+1 Calculate as follows: In the formula, The position vector of cable node i+1 at the n+1th time step; The position vector of cable node i+1 at the nth time step; The position vector of cable node i+1 at the n-1th time step; h: time increment step; m i+1 : The mass of the freight cableway load-bearing cable node i; The resultant force acting at the node i of the load-bearing cable at the nth time step; The first dynamic damping correction factor of the load-bearing cable node i+1; The second dynamic damping correction factor of the load-bearing cable node i+1; Wherein: the first dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated according to the following formula: In the formula, The original length of the load-bearing cable element i; The length from the load node p to the load cable node i+1 in the nth time step; The second dynamic damping correction coefficient of the load-bearing cable node i+1 is calculated as follows:

8. The method according to claim 7, characterized in that: The initial value of the motion equation of the load-bearing cable node or load node for the continuous motion of the load is calculated as follows: In the formula, x 0 : initial position vector of the cable node or load node; x -1 : The position vector of the cable node or load node at the -1th time step; x 1 : The position vector of the cable node or load node in the first time step, x -1 =x 0 ; m: mass of the load node; F 0 : The resultant force acting on the node when the load node passes through the saddle.

9. The method according to claim 5, characterized in that: The calculation of the load movement position when the freight ropeway load moves continuously includes: At the n+1th time increment, the position of the load node p is calculated as follows In the formula, The position of the load node p at the n+1th time increment; The position of the load node p in the nth time increment; Δx p : The load node movement position in each time increment h; Where Δx p =V p h: The load node movement position within each time increment h is calculated as follows: Δx p =V p ·h Where V p : Moving speed of load node p; h: Time increment step.

10. The method according to claim 1, characterized in that The freight ropeway parameters include: ropeway span, ropeway height difference, load-bearing rope unit weight, load-bearing rope cross-sectional area multiplied by elastic modulus, traction rope unit weight, traction rope cross-sectional area multiplied by elastic modulus and load mass.

11. A method and system for analyzing the continuous motion process of a freight ropeway load, characterized in that: include: Acquisition module, calculation module and verification module; Acquisition module: to obtain the parameters of the freight cableway load-bearing cable nodes and load nodes; Calculation module: bring the parameters of the load-bearing cable node and the load node of the freight cableway into the pre-established motion equations of the load-bearing cable node and the load node, increase the time step according to the set time increment step, solve the node motion equation, calculate the position vector and the resultant force of the load-bearing cable node and the load node in the next time step, until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable node and the load node in each time step; Verification module: verifying the maximum load-bearing capacity of the freight ropeway based on the maximum force value that the freight ropeway can bear and the position vectors and combined forces of the load-bearing rope nodes and the load nodes at each time step; The calculation module includes: solving the node motion equation at the current time step to obtain the position vector of the load-bearing cable node and the load node at the next time step; Calculate the resultant force of the load-bearing cable node and the load node at the next time step according to the position vectors of the load-bearing cable node and the load node at the next time step; Increase the time step according to the set time increment step until the preset time period ends, and obtain the position vector and the resultant force of the load-bearing cable node and the load node at each time step in the preset time period; The motion equations of the cable nodes and load nodes are as follows: Where: m: the mass of the cable node or load node, The acceleration of the load node or the load node; F n : The resultant force acting on the cable node or load node at the nth time step; f dmp : virtual damping force; Wherein, the virtual damping force is calculated as follows: Where, ζ: damping factor, ζ>0; The speed of the node; When the freight cableway node is a load-bearing cable node, the resultant force F acting on the load-bearing cable node at the nth time step is n Calculate as follows: F n =G i +f i n In the formula, G i : Gravity acting on the load-bearing cable node i, f i n : The resultant internal force of the load-bearing cable unit connected to the load-bearing cable node i at the nth time step; When the freight cableway node is a load node, the resultant force F acting on the load node at the nth time step n Calculate as follows: In the formula, G p : Load gravity, The resultant force of the internal forces of the load-bearing cable unit at the nth time step; is the virtual traction on the load node at the nth time step; p: is the load node of the i-th unit of the load-bearing cable at the nth time step, between the load-bearing cable node i and the node i+1.

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