A method and system for operating a rail-type transport trolley
By dividing the total stroke of the rail-type transport trolley into fast travel and end-point search stroke, and setting different speed sections and deceleration, the problem of target position deviation caused by slipping when the trolley is moving is solved, and the effect of quickly and accurately reaching the end point is achieved.
Patent Information
- Application Number
- CN202411857457.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-04-04
AI Technical Summary
In new energy battery swap stations, rail-type transport trolleys are prone to sliding relative to the actual walking surface when moving, resulting in target position deviations. Existing solutions such as adding gears or installing sensors have errors or increasing maintenance costs and time consumption.
By dividing the total stroke of the rail-type transport trolley into a fast travel and a end point search stroke, setting different speed segments and deceleration, and using technical means such as deceleration marking points and proximity switches, the trolley can travel at a faster speed during the fast travel, and decelerating at a smaller speed and a specific deceleration when approaching the end point.
It effectively reduces the time deviation of the transportation trolleys reaching the finish line, improves the accuracy of reaching the finish line, and reduces maintenance costs and time consumption.
Smart Images
Figure CN119759003A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of new energy battery swap stations, and in particular relates to an operation method and system of a rail-type transport trolley. Background Art
[0002] In new energy battery swap stations, RGV carts are usually used to transport batteries. In actual use, due to the influence of multiple factors such as the friction between the cart and the track, acceleration and deceleration, the cart that transports the batteries will slide relative to the actual walking surface when moving (i.e., slipping), resulting in the theoretical travel of the motor that drives the cart to move being greater than the actual travel of the cart, resulting in a deviation between the target position reached by the cart and the actual target position.
[0003] To solve this problem, there are two main design solutions on the market: one is to add gears between the walking mechanism and the actual walking surface to reduce the walking error value, but the error still exists, and the wear of the gears will increase the subsequent maintenance cost; the other is to install sensors from the outside to make the walking mechanism search for points at a slower speed, but this method of reducing speed for accurate positioning will take more time and affect the user experience. Summary of the invention
[0004] The object of the present invention is to provide an operation method and system of a rail-type transport vehicle to solve the problems raised in the above-mentioned background technology.
[0005] To achieve the above object, a technical solution adopted by the present invention is: a method for operating a rail-type transport vehicle, comprising the following steps:
[0006] A1: Determine the starting point Sb and the end point Sf of the total travel L of the transport vehicle, and divide the total travel L into a fast travel journey L1 and an end point search journey L2, where L1>L2;
[0007] A2: Set the maximum stable running speed V1 of the transport vehicle in the fast running interval L1 and the maximum stable running speed V2 in the terminal search interval L2, wherein V1>V2>0, and the average running speed of the transport vehicle in the L1 interval is greater than the average running speed in the L2 interval;
[0008] A3: A deceleration mark point is set near the end point Sf of the total stroke L. The distance from the deceleration mark point to Sf is Lm. By the formula a1=V2 2 / 2Lm to find the deceleration a1 of the transport vehicle in the Lm interval;
[0009] The transport trolley runs at a speed of V1 to the intersection of the fast travel stroke and the end-point search stroke, and then runs at a speed of V2 to a distance Lm from the end point of the total stroke, and then decelerates and stops at the end point Sf at a deceleration of a1.
[0010] Preferably, the operation method of the fast travel process is as follows:
[0011] B1: Set the acceleration a2 and deceleration a3 of the transport trolley in the fast travel interval, take the total travel L as the travel distance, and calculate the movement time of the transport trolley at the speed V1;
[0012] B2: Measure the running distance of the transport trolley in the fast travel interval multiple times, obtain the minimum difference between the total travel and the running distance, and set the difference as the minimum safety distance Ls;
[0013] B3: Travel Ls from the end point Sf toward the starting point Sb to the point where the intersection of L1 and L2 occurs.
[0014] Preferably, the acceleration of the transport vehicle in the end point search interval is set to a4, wherein a4>a2, and the absolute value of a3 is smaller than the absolute value of a1.
[0015] Preferably, in step B3, an absolute safety stroke La needs to be added, and the position of the intersection point of L1 and L2 is the position after traveling a distance of Ls from the end position Sf toward the starting position Sb, and then traveling a distance of La.
[0016] Preferably, with the end position Sf toward the starting position Sb as the direction, a relative safety distance Lr needs to be added at the intersection point determined by B3 to be a new intersection point of L1 and L2, wherein Lr=Ls.
[0017] Preferably, with the end position Sf toward the starting position Sb as the direction, Lm needs to be added at the intersection point determined by B3 as a new intersection point between L1 and L2.
[0018] The present invention also provides a rail-type transport trolley system for use with the above-mentioned operating method, comprising a transport trolley and a track, wherein a proximity switch is provided on the track, and when the proximity switch identifies the transport trolley, the transport trolley starts to decelerate at a deceleration of a1.
[0019] Preferably, the track is also provided with an extreme position limit switch for reminding the transport trolley when the running position of the transport trolley exceeds the terminal position.
[0020] Beneficial effects of the present invention: When the operating method of this scheme is actually used, the transport vehicle will travel most of the total distance at a faster speed, and then travel at a slower speed until it decelerates and stops at the terminal position when it reaches the deceleration mark point. The entire operating process travels most of the distance in a short time, thereby saving time. At the same time, it travels at a relatively slow speed during the remaining distance, effectively ensuring the accuracy of reaching the terminal position. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is the operation flow chart of the transport trolley of the present invention;
[0022] Figure 2 It is a schematic diagram of marking various points in the total travel of the transport trolley in the present invention. DETAILED DESCRIPTION
[0023] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.
[0024] Example:
[0025] A rail-type transport trolley system comprises a transport trolley and a track, wherein a proximity switch is arranged on the track, and at the same time, an extreme position limit switch is also arranged on the track for reminding the transport trolley when the running position of the transport trolley exceeds the terminal position. The proximity switch and the limit switch can adopt a contact mechanical structure, or a non-contact structural design using a sensor or the like.
[0026] Among them, see Figure 1 , Figure 2 The present invention also provides a method for operating a rail-type transport vehicle, comprising the following steps:
[0027] A1: Determine the starting point Sb and the end point Sf of the total travel L of the transport vehicle, and divide the total travel L into a fast travel journey L1 and an end point search journey L2, where L1>L2;
[0028] A2: Set the maximum stable running speed V1 of the transport vehicle in the fast running interval L1 and the maximum stable running speed V2 in the terminal search interval L2, wherein V1>V2>0, and the average running speed of the transport vehicle in the L1 interval is greater than the average running speed in the L2 interval;
[0029] A3: A deceleration mark point is set near the end point Sf of the total stroke L. The distance from the deceleration mark point to Sf is Lm. By the formula a1=V2 2 / 2Lm to find the deceleration a1 of the transport vehicle in the Lm interval;
[0030] The transport trolley runs at a speed of V1 to the intersection of the fast travel stroke and the end-point search stroke, and then runs at a speed of V2 to a distance Lm from the end point of the total stroke, and then decelerates and stops at the end point Sf at a deceleration of a1;
[0031] It should be noted that the starting point Sb and the end point Sf are relative to each other in the total travel distance L, that is, if the direction of the transport vehicle from the battery compartment to the vehicle position is positive, the starting point Sb is the battery compartment position; if the direction of the transport vehicle from the vehicle to the battery compartment position is positive, the starting point Sb is the vehicle position.
[0032] The operation method of the fast travel process is as follows:
[0033] B1: Set the acceleration a2 and deceleration a3 of the transport trolley in the fast travel interval, take the total travel L as the travel distance, and calculate the movement time of the transport trolley at the speed V1;
[0034] B2: Measure the running distance of the transport trolley in the fast travel interval multiple times, obtain the minimum difference between the total travel and the running distance, and set the difference as the minimum safety distance Ls;
[0035] B3: Travel Ls from the end point Sf toward the starting point Sb to the point where the intersection of L1 and L2 occurs.
[0036] Among them, the acceleration of the transport vehicle in the end-point search interval is set to a4, a4>a2, and the absolute value of a3 is smaller than the absolute value of a1. It should be noted that the calculation in this embodiment does not consider the vector direction, so the accelerations a2, a3 and the decelerations a1, a4 are all positive numbers.
[0037] In step B3, an absolute safety stroke La needs to be added. The position of the intersection point of L1 and L2 is the position after the end position Sf travels a distance of Ls toward the starting position Sb, and then travels a distance of La.
[0038] In which, with the end position Sf toward the starting position Sb as the direction, a relative safety distance Lr needs to be added at the intersection point determined by B3 to be the new intersection point of L1 and L2, and Lr=Ls.
[0039] Among them, with the end position Sf toward the starting position Sb as the direction, Lm needs to be added at the intersection point determined by B3 as the new intersection point of L1 and L2.
[0040] Specifically, it is necessary to select appropriate parameters to debug the transport trolley to determine the position of each point of the transport trolley under the total stroke. For example, assuming that the total stroke L = 2200mm, and assuming that the acceleration of the transport trolley in the travel range L1 is a2 = 500mm / s 2, deceleration a3 = 300 mm / s 2 , the maximum running speed V1=500mm / s. Through the calculation formula of displacement and speed, we can calculate the time when the transport trolley accelerates from 0 to V1 speed, the time when V1 decelerates to 0 and the time when the transport trolley maintains V1 speed under theoretical conditions. According to the above results, the actual distance traveled by the transport trolley on the 2200mm track is measured many times in the experimental environment. Assuming that the maximum travel distance obtained by multiple measurements is 2180mm, it means that the transport trolley must slip at least 20mm under the model conditions. In this way, the most basic fast travel stroke L1=2180mm and the end point search stroke L2=20mm can be obtained. At this time, Ls=L2=20mm, and the deceleration mark point is included in the stroke of L2.
[0041] Of course, in order to prevent the transport trolley from being infinitely close to the theoretical state during actual operation, an absolute safety stroke La needs to be added. For example, 20% of Ls can be used as La, that is, La = 4mm. At this time, L2 = 20 + 4 = 24mm, and L1 = 1176mm.
[0042] Among them, if the distance from the starting point Lb to 1176mm is taken as the theoretical end point of the transport trolley in the rapid travel range L1, it will be affected by 20mm slippage in actual use. The actual L1=1176-20=1156mm. At this time, in actual use, the transport trolley roughly stops at the position 1156mm from the starting point. By determining the length of the L1 path, the length of L2 can be effectively and reasonably designed.
[0043] Among them, in the process of conducting experiments on the total stroke L of the transport trolley to obtain Ls, in order to avoid the transport trolley from infinitely approaching the theoretical state during actual operation and to ensure that the transport trolley has a second end point to find the stroke interval L2, Lm should be regarded as an independent existence in the L2 interval, that is, if Ls = 20mm, the minimum L2 should be the sum of Ls and Lm.
[0044] In addition, when designing the motion parameters of the transport trolley in the L2 path, it should be ensured that the acceleration a4>a2 so that the transport trolley can start quickly, and the absolute value of a3 is less than the absolute value of a1 so that the transport trolley can stop quickly, thereby effectively ensuring the accuracy of the transport trolley's parking position. For example, in the L2 trip, assuming that the acceleration of the transport trolley = 1000mm / s 2 , the deceleration is 625mm / s 2 , then Lm=2mm at this time. Of course, according to the relevant formulas of displacement and velocity, we can know that the greater the deceleration in L2, the smaller Lm.
[0045] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A method for operating a rail-type transport vehicle, characterized in that: The following steps are involved: A1: Determine the starting point Sb and the end point Sf of the total travel L of the transport vehicle, and divide the total travel L into a fast travel journey L1 and an end point search journey L2, where L1>L2; A2: Set the maximum stable running speed V1 of the transport vehicle in the fast running interval L1 and the maximum stable running speed V2 in the terminal search interval L2, wherein V1>V2>0, and the average running speed of the transport vehicle in the L1 interval is greater than the average running speed in the L2 interval; A3: A deceleration mark point is set near the end point Sf of the total stroke L. The distance from the deceleration mark point to Sf is Lm. By the formula a1=V2 2 / 2Lm to find the deceleration a1 of the transport vehicle in the Lm interval; The transport trolley runs at a speed of V1 to the intersection of the fast travel stroke and the end-point search stroke, and then runs at a speed of V2 to a distance Lm from the end point of the total stroke, and then decelerates and stops at the end point Sf at a deceleration of a1.
2. The method for operating a rail-type transport vehicle according to claim 1, characterized in that: The operation method of the fast travel process is as follows: B1: Set the acceleration a2 and deceleration a3 of the transport trolley in the fast travel interval, take the total travel L as the travel distance, and calculate the movement time of the transport trolley at the speed V1; B2: Measure the running distance of the transport trolley in the fast travel interval multiple times, obtain the minimum difference between the total travel and the running distance, and set the difference as the minimum safety distance Ls; B3: Travel Ls from the end point Sf toward the starting point Sb to the point where the intersection of L1 and L2 occurs.
3. The method for operating a rail-type transport vehicle according to claim 2, characterized in that: The acceleration of the transport vehicle in the end point search travel interval is set to a4, where a4>a2, and the absolute value of a3 is smaller than the absolute value of a1.
4. The method for operating a rail-type transport vehicle according to claim 2, characterized in that: In step B3, an absolute safety stroke La needs to be added. The position of the intersection point of L1 and L2 is the position after traveling a distance of Ls from the end position Sf toward the starting position Sb, and then traveling a distance of La.
5. The method for operating a rail-type transport vehicle according to claim 2 or 4, characterized in that: With the end position Sf toward the starting position Sb as the direction, a relative safety distance Lr needs to be added at the intersection point determined by B3 to be the new intersection point of L1 and L2, where Lr=Ls.
6. The method for operating a rail-type transport vehicle according to claim 2, characterized in that: With the end point Sf toward the starting point Sb as the direction, Lm needs to be added at the intersection point determined by B3 as the new intersection point of L1 and L2.
7. A rail-type transport trolley system, operated using the operating method according to any one of claims 1 to 7, characterized in that: It comprises a transport trolley and a track, wherein a proximity switch is arranged on the track. When the proximity switch identifies the transport trolley, the transport trolley starts to decelerate at a deceleration of a1.
8. The rail-type transport vehicle system according to claim 6, characterized in that: The track is also provided with an extreme position limit switch for reminding the transport trolley when the running position of the transport trolley exceeds the terminal position.