Construction method of metro station batch cargo loading, unloading and carrying system

Abstract

The invention belongs to the field of underground logistics transportation, and particularly relates to a construction method of a metro station batch cargo loading, unloading and carrying system. Comprising the following steps: setting a metro freight vehicle overall structure, internal space arrangement and cabin door opening and closing control parameter calculation method; a metro freight vehicle built-in movable storage cage is configured; configuring a platform shielding door construction operation mode capable of being in butt joint with a subway freight vehicle and a platform cargo loading and unloading operation process; designing a subway platform logistics area warning tape arrangement scheme; configuring a platform layer cargo carrying path; constructing a subway platform-station hall interlayer cargo carrying vertical channel; and building a station hall layer cargo handling route and a station access channel. According to the invention, on the premise of not interfering the passenger transport service, the space utilization efficiency of the subway station, the rationality of machine configuration and the operation efficiency after the logistics function is added are improved, and the station is supported to rapidly process urban goods in batches.

Description

Technical Field

[0001] This invention belongs to the field of underground logistics transportation, specifically relating to a method for constructing a bulk cargo loading and unloading system for subway stations. Background Technology

[0002] With the continued growth in demand for urban e-commerce, fresh food delivery, and on-demand replenishment of manufacturing parts, urban logistics systems are facing higher requirements for delivery efficiency and operational stability. Current urban logistics mainly relies on surface road transportation, which is constrained by factors such as road traffic pressure, limited parking space, and delivery bottlenecks during peak hours, leading to overall operational bottlenecks. Subway systems, with their high punctuality, large capacity, and 24 / 7 operation, have become an important supplementary means for urban logistics to "reduce costs and increase efficiency" and expand delivery channels. In particular, utilizing subway systems for short-distance urban freight transportation has a solid resource base and development potential, showing significant advantages, especially in alleviating the "last mile" delivery pressure in central urban areas.

[0003] Currently, some cities have piloted "passenger-freight mixed" transportation during off-peak hours or at night, utilizing surplus capacity of subway trains. This involves setting up dedicated train carriages to carry freight units, and manually escorting arriving goods out of stations. This method has improved the utilization rate of subway trains and station space to some extent, providing an exploratory path for subway freight practices. However, the current station freight loading and unloading model lacks standardized and efficient processing procedures; freight handling routes overlap significantly with station passenger service areas, leading to decreased station traffic efficiency and safety hazards. Furthermore, nighttime operations are constrained by operational maintenance and equipment load limitations, making it difficult to meet the demands of high-frequency freight circulation.

[0004] Subway station spaces generally consist of three basic areas: a public area, an equipment area, and a track area. The public area refers to all areas that passengers may pass through during entry, exit, and train travel, and is divided into the passenger concourse and passenger platform areas according to spatial hierarchy. The subway station equipment area includes three functional zones: an office and living area, a system area, and an electromechanical equipment area, supporting the daily operation and management of the station. To enable rapid loading, unloading, and handling of arriving goods, it is necessary to modify the facilities, equipment, and passageways originally located in the passenger platform and equipment areas to a certain extent, such as using new platform screen doors, installing vertical freight elevators, etc., and replanning the freight flow paths within the station to achieve efficient connections between trains, personnel, and the station, meeting the time and space requirements for high-frequency freight transportation using the subway system. Summary of the Invention

[0005] The purpose of this invention is to provide a method for constructing a bulk cargo loading and unloading system for subway stations.

[0006] The technical solution to achieve the purpose of this invention is: a method for constructing a bulk cargo loading and unloading system in a subway station, comprising the following steps:

[0007] Step (1): Set up the calculation method for the overall structure, internal space layout and door opening and closing control parameters of the subway freight car;

[0008] Step (2): Configure the subway freight car with built-in mobile storage cage;

[0009] Step (3): Configure the platform screen door structure and operation mode that can be connected to subway freight vehicles, and the platform cargo loading and unloading operation process;

[0010] Step (4): Design a plan for the layout of warning tape in the logistics area of ​​the subway platform;

[0011] Step (5): Configure the cargo handling path on the platform level;

[0012] Step (6): Construct a vertical passage for cargo handling between the subway platform and the concourse;

[0013] Step (7): Construct the cargo handling route and access channels to and from the station hall.

[0014] Furthermore, step (1) specifically includes:

[0015] Step (11): Overall structure of the subway freight car:

[0016] The metro freight car has the same structural dimensions as the existing metro train. The height of the metro freight car's floor is no different from that of the platform. The chassis structure of the metro freight car is a sandwich box-shaped main beam. The chassis has standardized installation interfaces arranged laterally. Wide sliding-folding combination doors are set on the left and right sides of the car body. The door structure is composed of double-layer lightweight composite panels and a high-rigidity frame. The side walls of the car body have recesses for storing the folding doors.

[0017] Step (12): Interior space layout of subway freight cars:

[0018] The interior space of the subway freight car is divided into multiple standard slots arranged longitudinally along the vehicle. Each slot is equipped with guide rollers and quick-lock devices at the bottom to guide the storage cages to position and lock them in place. Foldable seats are partially installed on the internal side walls, and embedded sliding rails are arranged on the top for temporary installation of hanging devices or transportation of non-standard goods.

[0019] Step (12): The calculation method for the opening and closing control parameters of the subway freight car doors is as follows:

[0020] Dwell time at a single station t s In a subway freight scenario with frequent stops (no more than 60 seconds), the complete opening and closing time T of the cargo door is... c as follows:

[0021]

[0022] In the formula, L s For the sliding stroke; θ f For the folding angle; v s ω is the average velocity during the slip phase. f The average angular velocity during the folding phase;

[0023] To ensure that the door does not interfere with the vehicle body cavity during the sliding separation process, the expression is as follows:

[0024] D r ≥D m +δ

[0025] In the formula, D r D represents the depth of the storage compartment. m δ represents the door leaf thickness; δ represents the assembly clearance.

[0026] Thrust F required during the slip phase s The calculation formula is as follows:

[0027]

[0028] In the formula, T e The motor torque is r; the lead screw radius is m. d The mass of the door is μ; the coefficient of rolling friction is g; g is the acceleration due to gravity.

[0029] Metro freight car door motor power P m The expression is as follows:

[0030]

[0031] In the formula, T m P represents the instantaneous output torque of the drive motor, expressed in N·m. calc ω represents the theoretically calculated power actually required by the system during operation. m η is the rated angular velocity of the motor. m The value is the transmission efficiency; the coefficient χ is the safety margin coefficient, with a value of 1.2.

[0032] Furthermore, step (2) specifically includes:

[0033] Step (21): The structure of the mobile storage cage built into the subway freight car is as follows:

[0034] The storage cage body is a load-bearing frame formed by welding high-strength aluminum alloy profiles. The four corners of the frame are equipped with stamped reinforcing corner plates and reserved lifting ring holes. The frame is surrounded by foldable mesh sidewalls. The bottom of the storage cage is covered with a wear-resistant composite plate. Polyurethane rollers are arranged longitudinally along the lower edge of the composite plate and guide racks are embedded. The rollers are connected to the bottom plate of the storage cage via spring damping seats. Four-point weighing sensor interfaces are arranged inside the bottom plate.

[0035] Step (22): The specific calculation method for the design control parameters of the built-in mobile storage cage in the subway freight car is as follows:

[0036] The three-dimensional datum dimensions of the cage are determined by the following expressions:

[0037]

[0038] In the formula, L c W c H c These represent the design reference dimensions of the cage in the length, width, and height directions, respectively; L lim W lim H lim These represent the limit values ​​of the cage's external dimensions in the length, width, and height directions, respectively; △ represents the clearance of the vehicle's cargo compartment.

[0039] When the storage cage moves along the platform roller line or vehicle rail, the pushing resistance is considered as rolling resistance, specifically:

[0040] F rr =μ r ×(Q n +M c )×g ​​(6)

[0041] In the formula, F rr For rolling resistance; μ r Q is the coefficient of friction between the roller and the track; n The maximum set loading mass load for a single storage cage; M c The weight of the storage cage itself;

[0042] To achieve single-person escort or AGV-assisted pushing, a thrust F is designed. push It should satisfy: F push ≥φF rr , where φ is the operating margin coefficient;

[0043] Step (23): Number of storage cage rollers n w With single wheel ultimate load C w Satisfy the following formula:

[0044]

[0045] In the formula, C wP represents the ultimate load-bearing capacity of a single roller. w The actual load-bearing capacity of each roller; coefficient λ is the load redundancy coefficient.

[0046] Furthermore, the specific operation mode of the platform screen doors in step (3) is as follows:

[0047] Platform screen doors include standard passenger section screen doors and passenger / freight section screen doors. The passenger / freight section screen doors are located at both ends of the platform, aligned with the doors of the first and last subway train cars, respectively. The width of the screen doors is adapted to the effective opening surface of the freight doors. When connecting to the freight cars of the subway train, the screen doors open to the same width as the freight car doors. When the train is a purely passenger train, the screen doors can also connect to the passenger car doors and open synchronously with other standard passenger section screen doors.

[0048] The platform screen doors in the passenger and freight shared section adopt an electric-driven sliding one-way opening mechanism, equipped with a 24V low-voltage DC motor and a lead screw guide rail system. During the opening and closing of the platform screen doors, their operating status is transmitted back to the platform PLC in real time through position sensors, and at the same time, data is synchronized with the subway dispatch center through the signal bus.

[0049] Furthermore, step (5) specifically involves:

[0050] Step (51): Discretize the passable surface into grid nodes based on the platform building plane coordinate system, define the loading and unloading port P0(x0,y0) of the first or last carriage, the platform end platform screen door passage P1, the equipment area entrance P2, and the vertical freight elevator car entrance P3; Under the constraints of "not crossing the waiting area, not cutting across the evacuation passage, and minimum turning radius ≥ r-{min}", use the weighted shortest path model to plan the horizontal path of cargo handling, as shown in the following expression:

[0051]

[0052] In the formula, d i θ is the length of the i-th path segment; i α1 represents the turning angle between adjacent line segments; β1 and β1 correspond to the straight-going and turning cost weights, respectively, where β1 > α1 is used to suppress frequent turns; n is the number of line segments in the path.

[0053] Step (52): The path search uses the A* algorithm, and the heuristic function is Euclidean distance. After obtaining the node sequence {P0, P1, P2, P3}, the straight lines and arcs between each node are smoothed to ensure that the turning radius of the storage cage does not exceed r. min =1.2m; After completing the horizontal path, calculate the total pushing resistance, as shown in the following expression:

[0054]

[0055] In the formula, μ r γ is the rolling friction coefficient; γ1 is the steering additional resistance factor; Q n Set the maximum load capacity for the storage cage; M c The weight of the storage cage itself;

[0056] Step (53): The vertical freight elevator dispatch adopts a "first-come, first-served" strategy: the elevator is called when the car is at the station hall and idle; if it is in operation, the waiting time t is calculated. w =t cycle -t elapsed Only when t w <t thr Only if a waiting period is arranged, otherwise, the passenger will be switched to another backup freight elevator; the total travel time is calculated using the following formula:

[0057]

[0058] In the formula, t cycle The time for one complete elevator cycle; t elapsed t represents the running time of the current cycle. thr The set acceptable waiting time threshold; T is the total handling time along the entire path; d i v is the length of the i-th segment of the transport path; push The speed of manual pushing; t w For elevator waiting time; t lift This refers to the lifting and lowering time of the freight elevator.

[0059] Furthermore, step (6) of constructing the vertical cargo handling passage between the subway platform and the concourse is specifically as follows:

[0060] Step (61): Determine the net dimensions inside the car:

[0061] B = W c +2Δ c D = L c +Δ c H = H c +1000 (11)

[0062] In the formula, B, D, and H represent the net width, depth, and height of the freight elevator, respectively; L c W c H c These are the length, width, and height of the subway freight storage cage, respectively; △ c Minimum safety clearance in both the lateral and longitudinal directions;

[0063] Step (62): Determine the rated load Q of the vertical channel. e :

[0064] Q e =k s ×(Qn +M c (12)

[0065] In the formula, Q n The maximum set loading mass load for a single storage cage; M c For cage weight; k s For safety factor;

[0066] Step (63): The car lifting speed v is obtained based on the stopping window Δt(s), and the expression is as follows:

[0067] t lift =Δt-t 装卸 -t 启停缓冲 (13)

[0068] In the formula, h is the height from the platform to the concourse level, in meters (m); t lift Δt is the elevator car lifting time; Δt is the total train stop window time; t 装卸 For horizontal push time; t 启停缓冲 To provide a buffer for the car's start and stop;

[0069] Step (64): Determine the elevator drive motor power P and the brake force F. b The expression is as follows:

[0070]

[0071] F b ≥τ×(Q e +0.5M s )×g ​​(15)

[0072] In the formula, P is the power required by the elevator drive motor; Q e The rated load of the elevator; σ is the unit conversion factor; η is the overall efficiency; M s τ is the self-weight of the elevator guide rail / car system; τ is the safety factor.

[0073] Furthermore, step (7) constructs the cargo handling routes and station access channels at the station concourse level, including the station concourse self-pickup mode, the entrance / exit elevator transfer mode, and the equipment area direct-to-ground mode, specifically as follows:

[0074] The station hall is gridded, and the equipment area exit P is defined. S With target node P t Planning cost function:

[0075]

[0076] In the formula, C(P) is the total cost of path P; d i Let θ be the length of the i-th straight path segment; iLet be the i-th turn in the path; z is the degree of overlap with passenger flow; α2, β2, and γ2 are the weight coefficients of each factor, where α2 < β2 < γ2 indicates that the cost of turning and conflict with passenger flow is higher than that of straight segments;

[0077] A*-Lite search is used to output three shortest feasible paths and avoid high-traffic areas online; for entrance / exit transfer elevator modes and equipment area direct-to-ground modes, a vertical distance h is added to the end point of the path. c The total time expression is as follows:

[0078]

[0079] In the formula, T c v represents the total handling time. push The speed at which the storage cage is manually pushed; h c The vertical distance to the endpoint; v lift To increase the speed of the elevator; t 启停缓冲 This is the buffer time for system response and start / stop.

[0080] Compared with the prior art, the significant advantages of this invention are:

[0081] This invention proposes a rapid loading and unloading system and construction method for bulk goods in subway stations. The overall deployment is completed in a progressive manner, following the vehicle system, platform interface, horizontal passageways, vertical passageways, and concourse / ground distribution. It provides a complete technical path encompassing vehicle door design, storage cage configuration, platform screen door modification, platform and equipment area logistics channel connection, vertical freight elevator layout, and concourse freight flow organization. This helps shorten the freight transfer time during train stops, controlling the loading and unloading time of a single train to within 60 seconds, ensuring no interference between passenger and freight transport, and improving subway operational efficiency. The entire solution adopts modular components for external installation, achieving semi-automated flow processing and through-train transport capabilities for arriving goods without large-scale underground renovation projects. This significantly reduces the implementation cost and difficulty of subway freight transport, promotes the transformation of urban ground distribution models to underground three-dimensional transfer systems, alleviates ground road traffic pressure, contributes to urban freight transport carbon reduction, and provides convenient and fast smart logistics distribution services.

[0082] The system and method proposed in this invention achieve engineering and operational innovations by integrating a vertical connection between trains, stations, and concourses, ensuring that passenger levels remain unobstructed and freight traffic continues uninterrupted. This prevents station dwell time from being extended, waiting areas from being compressed, and significantly reduces the number of ground delivery vehicles, thereby reducing congestion and emissions, freeing up ground space, and improving the layout rationality and operability of subway stations after incorporating logistics functions. It provides a scalable path for large-scale urban logistics distribution using subway stations as hubs, and has significant social, economic, and environmental benefits. Attached Figure Description

[0083] Figure 1 This is a schematic diagram of the rapid loading, unloading, and handling system for bulk goods in subway stations proposed in this invention, as well as its construction method.

[0084] Figure 2 This is a schematic diagram of the overall structure and internal space layout of the subway freight vehicle proposed in this invention.

[0085] Figure 3 This is a schematic diagram of the structure of the built-in mobile storage cage in the subway freight vehicle proposed in this invention.

[0086] Figure 4 This is a schematic diagram of the structure of the subway platform dual-purpose passenger and freight screen door proposed in this invention.

[0087] Figure 5 This is an example of the arrangement and deployment scheme of warning tape in the logistics area of ​​a subway platform proposed in this invention.

[0088] Figure 6 This is a schematic diagram of the cargo routing plan for the subway station platform level proposed in this invention.

[0089] Figure 7 This is a schematic diagram of the cargo handling space structure on the platform level of a subway station proposed in this invention.

[0090] Figure 8 This is a schematic diagram of the vertical cargo handling passage between subway platform and concourse levels proposed in this invention.

[0091] Figure 9 This is a diagram showing the result of cargo movement path planning in the concourse of a subway station in an embodiment of the present invention.

[0092] Explanation of reference numerals in the attached figures:

[0093] 21-Layered shelving; 22-Internal shielding door of the carriage; 23-Storage cage; 24-Quick-lock latch; 25-Folding seat; 31-Mesh sidewall; 32-Lifting ring hole; 33-Reinforced corner plate; 34-Bearing frame; 35-Hidden hinge; 36-Spring lock; 37-Polyurethane roller assembly; 38-RFID tag; 41-Window; 42-Groove inflatable sealing ring; 43-Door body; 43-Handrail; 71-Continuous lighting strip; 72-Platform equipment area; 73-Vertical freight elevator; 74-Yellow guide markings; 75-Foldable guardrail; 76-Platform end shielding door; 77-Pedestrian; 81-Car; 82-Storage cage; 83-Guide rail groove; 84-Modible locking device. Detailed Implementation

[0094] The present invention will now be described in further detail with reference to the accompanying drawings.

[0095] A rapid loading, unloading, and handling system for bulk goods in a subway station and its construction method include the following steps:

[0096] Step (1): Set the spatial structure and door opening and closing method of the subway freight car, including the overall structure and internal space layout of the subway freight car, and the calculation method of the control parameters for opening and closing of the subway freight car doors.

[0097] Step (2): Configure the built-in mobile storage cage of the subway freight car, including the basic structure of the subway freight storage cage and the calculation method of the design control parameters of the subway freight storage cage.

[0098] Step (3): Configure platform screen doors that can be connected to subway freight vehicles and platform cargo loading and unloading operation procedures, including the structure and operation mode of subway platform passenger and freight dual-purpose screen doors, control parameters of subway platform passenger and freight dual-purpose screen doors, and subway platform batch cargo rapid loading and unloading operation procedures.

[0099] Step (4): Design a warning tape layout plan for the logistics area of ​​the subway platform, including the layout range of the warning tape and the operation process of the warning tape deployment and retraction.

[0100] Step (5): Configure the cargo handling space and path on the platform level, including the cargo handling path planning method for the subway platform area, the platform end screen door structure modification method, and the logistics channel layout method for the platform equipment room area outside the end door.

[0101] Step (6): Construct a vertical passage for cargo handling between subway platform and station hall levels, including the basic structure of the vertical passage for cargo handling between station levels and the calculation method for the configuration parameters of the vertical passage for cargo handling between station levels.

[0102] Step (7): Construct the cargo handling route and access channels to and from the station hall, including the cargo handling operation process and cargo movement path planning method in the station hall.

[0103] Furthermore, the overall structure and internal space layout of the metro freight vehicle in step (1) are as follows: an overall structure based on a wide sliding-folding cargo door and a fully automatic end coupler is adopted.

[0104] The metro freight cars adopt a body design with the same height as conventional passenger cars, slightly shorter than conventional passenger cars. The width and height remain consistent with existing metro trains to adapt to existing lines and platform systems. The vehicle floor height is identical to the platform height, and the top profile follows standard clearances, facilitating coordinated configuration of facilities such as platform screen doors, tunnel cross-sections, and overhead contact lines. The chassis structure is a sandwich box-shaped main beam with standardized installation interfaces arranged laterally, facilitating the later addition of weighing sensors, attitude detection modules, and other devices. Wide sliding-folding combination doors are installed on both sides of the car body. The door structure consists of double-layer lightweight composite panels and a high-rigidity frame. When opening, the door first slides laterally away from the bulkhead, then folds inward into recessed grooves in the side wall of the car body, without occupying platform clearance.

[0105] The interior space of the cargo compartment is divided into multiple standard compartments based on a modular layout. Each compartment is equipped with guide rollers and quick-lock devices at the bottom to guide the storage cages into position and secure them. The compartments are arranged longitudinally along the vehicle. Foldable seats are partially installed on the side walls to meet short-term seating and emergency needs. Embedded sliding rails are installed on the top of the cargo compartment for temporary installation of lifting devices or transport of non-standard goods.

[0106] Furthermore, the calculation method for the opening and closing control parameters of the subway freight car doors in step (1) is as follows:

[0107] (1) At high-frequency stops (single-station dwell time t) s In a subway freight scenario (not exceeding 60 seconds), the complete opening and closing time T of the cargo door is... c A sufficient window period must be allowed for loading and unloading of storage cages, as shown in the following expression:

[0108]

[0109] In the formula, L s For the sliding stroke; θ f v is the folding angle (taken as 90°); s ω is the average velocity during the slip phase. f This represents the average angular velocity during the folding phase.

[0110] (2) Ensure that the door does not interfere with the vehicle body cavity during the sliding separation process, as shown in the following expression:

[0111] D r ≥D m +δ (2)

[0112] In the formula, D r D represents the depth of the storage compartment. m δ represents the door leaf thickness; δ represents the assembly clearance, which is a value determined by a combination of door manufacturing tolerances and vehicle vibration margin.

[0113] (3) Regarding drive matching, calculate the thrust F required during the slip phase. sThe expression is as follows:

[0114]

[0115] In the formula, T e The motor torque is r; the lead screw radius is m. d denoted as denoted as the mass of the door; μ as the coefficient of rolling friction; and g as the acceleration due to gravity.

[0116] (4) Verify the power P of the subway freight car door motor m The expression is as follows:

[0117]

[0118] In the formula, T m P is the instantaneous output torque (N·m) of the drive motor. calc ω represents the theoretically calculated power actually required by the system during operation. m η is the rated angular velocity of the motor. m The value is the transmission efficiency; the coefficient χ is the safety margin coefficient, which is generally taken as 1.2.

[0119] Furthermore, the basic structure of the subway freight storage cage in step (2) is as follows: the cage body is welded from high-strength aluminum alloy profiles to form a load-bearing frame. The four corners of the frame are equipped with stamped reinforcing corner plates and reserved hoisting ring holes. The frame is surrounded by foldable mesh sidewalls. The mesh is made of plastic-coated steel wire to take into account both ventilation and preventing scattering. The door is opened and closed with one button through a hidden hinge and spring lock. The bottom of the storage cage is laid with wear-resistant composite board. Polyurethane roller groups are arranged longitudinally under the board and embedded with guide racks. The rollers are connected to the bottom plate through spring damping seats, which can automatically adapt to the small height difference between the vehicle slot rails and the platform roller lines. Anti-detachment guide rods are added at the bottom corners to suppress lateral displacement when the subway train brakes or passes through curves. The front and rear ends of the cage body are equipped with quick-release locking interfaces. The self-resetting cam mechanism cooperates with the vehicle slot locking block. Insertion locks and removal unlocks. The locking or unlocking time is generally no more than 2 seconds. To achieve full-process information tracking, a passive radio frequency identification electronic tag (RFID) and a QR code nameplate are integrated in the front left corner, and a Bluetooth Low Energy (BLE) tag port is reserved in the rear right corner. Four weighing sensor interfaces are arranged inside the base plate to facilitate the real-time reading of load data by the subway train control system.

[0120] Furthermore, the specific calculation method for the design control parameters of the subway freight storage cage in step (2) is as follows:

[0121] (1) Determine the three-dimensional reference dimensions of the cage to ensure that there is no interference during loading and unloading. The expression is as follows:

[0122]

[0123] In the formula, L c Wc H c These represent the design reference dimensions of the cage in the length, width, and height directions, respectively; that is, the control dimensions actually used for design and manufacturing. L lim W lim H lim These represent the limit values ​​of the cage's external dimensions in the length, width, and height directions, respectively, which are the physical structural limit dimensions of the vehicle's cargo compartment or passageway; △ represents the clearance of the vehicle's cargo compartment slots.

[0124] (2) When the storage cage moves along the platform roller line or vehicle rail, the pushing resistance is mainly rolling resistance, specifically:

[0125] F rr =μ r ×(Q n +M c )×g ​​(6)

[0126] In the formula, F rr For rolling resistance; μ r Q is the coefficient of friction between the roller and the track; n The maximum set loading mass load for a single storage cage; M c The weight of the storage cage itself.

[0127] To achieve single-person escort or assisted pushing by automated guided vehicles (AGVs), a thrust F is designed. push It should satisfy: F push ≥φF rr , where φ is the operating margin coefficient.

[0128] (3) Number of storage cage rollers n w With single wheel ultimate load C w It should satisfy the following expression:

[0129]

[0130] In the formula, C w P represents the ultimate load-bearing capacity of a single roller. w The actual load on each roller is denoted by λ, which is the load redundancy coefficient. To suppress the risk of amplified rolling resistance or damage caused by overload, it is generally set to 0.8.

[0131] Furthermore, the specific structure and operation mode of the subway platform passenger and freight dual-purpose platform screen doors in step (3) are as follows:

[0132] The new subway platform screen doors consist of two parts: standard passenger screen doors and shared passenger / freight screen doors. The shared passenger / freight screen doors are located at both ends of the platform, aligned with the sliding-folding doors of the first and last subway train cars, respectively. The width of the screen doors has been increased to accommodate the effective opening surface of the freight car doors. When connecting to a freight car of a subway train, the screen doors open to the same width as the freight car doors; when the train is a purely passenger train, the screen doors can also connect to the passenger car doors and open synchronously with other standard passenger screen doors. The shared passenger / freight screen doors use a lightweight, high-strength composite material frame structure with embedded stainless steel reinforcing ribs and pre-installed grooved inflatable sealing rings around the door body. The outer layer of the door panel is made of wear-resistant aluminum-magnesium alloy plate, and the inner layer is a honeycomb sandwich panel, to reduce weight while maintaining rigidity.

[0133] The platform screen doors in the shared passenger and freight section employ an electrically driven sliding one-way opening mechanism, equipped with a 24V low-voltage DC motor and a lead screw guide system, enabling high-frequency opening and closing operations. During the opening and closing process, the operating status (open / closed / not in position) of the screen doors is transmitted in real time to the platform PLC (a programmable logic controller installed on the platform, mainly used to control the platform's signal system, train detection, door control, etc.) via position sensors. Simultaneously, data synchronization is maintained with the subway dispatch center via a signal bus to ensure operational safety. If abnormal resistance or position stagnation is detected during the opening and closing process, the system immediately triggers an emergency stop and alarm, ensuring the reliability of platform operations in different modes of subway passenger and freight intermodal transport.

[0134] A light curtain sensor is embedded inside the doorpost to detect intrusions within a height range of 50–1400 mm. A capacitive anti-pinch sensor strip is installed along the bottom edge of the door; when an object is detected being pinched, an emergency stop is immediately triggered and the door opens approximately 100 mm in the reverse direction. The entire door leaf is also equipped with an integrated stress monitoring strip to collect real-time data on changes in the door frame stress and share this data with the train control system. During operation, the system uses an adaptive algorithm for opening and closing speed to ensure the door is fully open or fully closed within 4 seconds, and completes the synchronous movement of the cargo hold door and the loading and unloading of storage cages within the remaining time, thereby ensuring the rapid and safe loading and unloading of bulk cargo.

[0135] Furthermore, the specific control parameters for the passenger and freight platform screen doors in step (3) are as follows:

[0136] (1) Determine the opening (or closing) time of the passenger and freight platform screen doors of the subway station, as shown in the following expression:

[0137]

[0138] In the formula, t is the time for the platform screen door to open or close; S is the door travel distance; v max n is the maximum linear velocity of the door body; p is the driving wire pitch; n r This represents the motor speed.

[0139] (2) The opening or closing time t of the platform screen door must satisfy the following expression:

[0140] 2t≤Δt-t 缓冲 (9)

[0141] In the formula, △t is the total window time for train stops, which is usually 30 to 60 seconds; t 缓冲 The buffer time used for the slow opening and synchronization delay of the hatch is usually 6 to 9 seconds.

[0142] (3) Determine the driving torque (friction approximation) of the passenger and freight platform screen doors of the subway station, as shown in the following expression:

[0143] T r ≥θ·T d (10)

[0144] In the formula, T d The minimum torque required for driving; T r The rated output torque of the motor; m d θ is the door weight; μ is the coefficient of friction of the slide rail or roller; p is the screw pitch; θ is the safety margin coefficient, which is generally taken as 1.3.

[0145] (4) The linear acceleration of the platform screen doors for both passenger and freight use in subway stations is specified in the following expression:

[0146]

[0147] In the formula, a is the linear acceleration of the door when it starts or stops; v max S represents the maximum linear velocity of the gate; S is the sliding stroke of the gate; limit: 0.8 m / s 2 This is to prevent violent impacts to the door, enhance passenger / cargo safety, and improve the smoothness of motor control.

[0148] (5) The amplitude deviation of the passenger and freight platform screen doors in the closed state of the subway station is specified by the following expression:

[0149] ε=W d -(W v -δ v (12)

[0150] In the formula, W d Effective opening / closing radius (mm); W v δ is the width of the vehicle door. v For positioning error, |ε| ≤ 20mm; if this limit is exceeded, the system will automatically reduce v. max up to 0.2v max And then realignment is performed. The above formulas for time, torque, acceleration, and amplitude together ensure that the platform screen door can quickly, smoothly, and accurately complete full opening and closing within the limited stopping window.

[0151] Furthermore, the specific process for rapid loading and unloading of bulk goods on the subway platform in step (3) is as follows: After the train arrives at the track area stopping position, the train-station communication system first performs position verification and coupler status confirmation; when the vehicle stops, the coupling lock signal and the platform screen door closing signal are both determined to be valid by the train control center, the system issues the "loading and unloading preparation" command, and at the same time switches the platform warning light strip to yellow flashing and starts the light curtain shielding. Then the platform screen door and the vehicle cargo door enter the linkage opening stage. The platform screen door servo driver first opens at a preset low speed of about 50mm to complete the alignment verification, and then pushes it to full opening at full speed. The on-board PLC sends an "unlock" signal, the slot quick-release lock hook is released, the escort personnel push the storage cage to the platform screen door line and the RFID is successfully identified by the ground reader. Then the platform escort personnel or AGV take over and continue to guide the storage cage to the vertical freight elevator located in the subway equipment area on the platform level; throughout the process, the light curtain sensor and the weighing unit monitor the channel status in real time. If a blockage or overload is detected, a pause is triggered and an alarm is triggered at both ends of the train and the ground. Once all storage cages have been handed over, the cargo door closes slowly to 50mm and enters a buffer compression phase; the platform screen doors close simultaneously after confirming the sealing rings have been depressurized. Finally, the train control system receives the "platform safe ready" instruction, restores the passenger safety circuit, and requests departure from the station from the train dispatcher. The above loading / unloading-opening / closing process is generally required to be completed within a 30-60 second stop window to ensure it is basically synchronized with passenger boarding and alighting times and does not affect subsequent train operations.

[0152] Furthermore, the specific layout of the warning tape in step (4) for the platform logistics area is as follows: the warning tape is set along the corresponding platform section of the freight car, with an embedded retractable structure preferred, a tape width of 120-150mm, and a yellow and black diagonal stripe color. The bottom surface of the entire warning tape is covered with an anti-slip rubber layer, and fiber optic reflective strips are installed every 1m along the long side to ensure that the boundary of the work area can still be clearly identified in low-light environments.

[0153] The longitudinal starting and ending points are defined by extending 0.5m beyond the clear width of the subway train's cargo door on both sides. The lateral distance from the platform edge is generally no less than 0.8m, and the overall length is no less than 1.5 times the clear width of the cargo door, ensuring complete coverage of the loading / unloading area and personnel movement zone. A 200mm buffer zone is reserved between the leading edge of the warning tape and the platform curtain wall to accommodate telescopic roller rails and roller conveyor transition components; the trailing edge maintains a 300-350mm gap from the regular yellow waiting line, achieving a double-layer visual cues through color difference. Flexible end caps with embedded magnetic positioning plates are installed at both ends of the tape, allowing it to unfold or retract within 3 seconds using a manual or electric retraction device. On curved platforms or end areas with protruding equipment rooms, the warning tape follows the platform curvature, with additional 30° chamfered buffer plates at corners to prevent scratching the cargo cage.

[0154] Furthermore, the specific procedure for the warning tape deployment and retraction in step (4) is as follows: When the train is about to enter the station and the train control center sends out the "freight operation" instruction, the platform staff first issue a reminder through public broadcast to guide waiting passengers to move to the outside of the regular yellow line, and use hand gestures to assist in evacuation, ensuring that no passengers remain within 0.8m of the front edge of the operation area. After the passengers are evacuated, the staff unlocks the rewind box and pulls the warning tape horizontally towards the train body. The tape is quickly attracted to the preset positioning plate through the magnetic end cap, forming a continuous isolation line. After the train loading and unloading is completed and the train-station reset signal is received, the staff presses the rewind switch of the rewind box, and the warning tape is automatically retracted. The portable fence is folded and placed in the equipment cabinet and the magnetic end cap is closed, restoring the normal passenger flow organization of the platform.

[0155] Furthermore, the specific method for planning the cargo handling path in the subway platform area in step (5) is as follows:

[0156] (1) Using the platform building plane coordinate system as a reference, the passable surface is discretized into grid nodes, defining the loading and unloading port P0(x0,y0) of the first (or last) car, the platform end platform screen door passage P1, the equipment area entrance P2, and the vertical freight elevator car entrance P3. This must satisfy the following conditions: it does not cross the waiting area, does not cut across evacuation routes, and has a minimum turning radius ≥ r. - Under constraints such as "{min}", a weighted shortest path model is used to plan the horizontal path for cargo handling, as shown in the following expression:

[0157]

[0158] In the formula, d i θ is the length of the i-th path segment; i α1 represents the turning angle between adjacent line segments; β1 and β1 correspond to the straight-going and turning cost weights, respectively (β1>α1 is used to suppress frequent turns); n is the number of line segments in the path (i.e., the number of line segments into which the path is divided).

[0159] (2) The path search uses the A* algorithm, and the heuristic function is Euclidean distance. After obtaining the node sequence {P0, P1, P2, P3}, the straight lines and arcs between each node are smoothed to ensure that the turning radius of the storage cage does not exceed r. min =1.2m. After completing the horizontal path, calculate the total pushing resistance, as shown in the following expression:

[0160]

[0161] In the formula, μ r γ is the rolling friction coefficient; γ1 is the steering additional resistance factor; Q n Set the maximum load capacity for the storage cage; M c The weight of the storage cage. If F exceeds the upper limit of manual pushing force F... maxIf so, an auxiliary electric traction module will be automatically added.

[0162] (3) The vertical freight elevator dispatch adopts a "first-come, first-served" strategy: the elevator is called immediately when the car is at the concourse level and idle; if it is in operation, the waiting time t is calculated. w =t cycle -t elapsed Only when t w <t thr A waiting period of 25 seconds or less is allowed; otherwise, the passenger will be switched to another backup freight elevator. The total path time estimation formula is as follows:

[0163]

[0164] In the formula, t cycle The time for one complete elevator cycle; t elapsed t represents the running time of the current cycle. thr The set acceptable waiting time threshold; T is the total handling time along the entire path; d i v is the length of the i-th segment of the transport path; push The speed of manual pushing; t w For elevator waiting time; t lift This refers to the lifting and lowering time of the freight elevator.

[0165] Through the above-mentioned shortest path, resistance verification and elevator control logic, it is ensured that the entire process of the storage cage from the loading and unloading port of the carriage, through the end of the platform, through the equipment area and up to the station hall by the freight elevator does not interfere with the passenger flow.

[0166] Furthermore, the specific method for modifying the platform end screen door structure in step (5) is as follows: remove the existing glass door or partition components, and retain the original top beam and wall structure. A new "side-sliding freight screen door" is installed at the original channel axis position. The door body is composed of a lightweight metal frame and a high-strength transparent composite panel. The door width is designed to allow a single fully loaded subway freight storage cage to pass smoothly. The door opening and closing method adopts an embedded sliding guide rail mechanism. The drive mechanism is an integrated electric screw sliding assembly, equipped with a travel limit switch and a door locking mechanism. In terms of control logic, the door opening signal is linked with the train stopping, freight mode activation, and vehicle end door opening signal. It is only authorized to open during freight operation and remains locked during daily operation. The door opening and closing status is fed back to the platform PLC in real time through a bidirectional position sensor and synchronized with the vehicle freight dispatching system signal to prevent the train from starting when the door is not closed.

[0167] Furthermore, the specific method for arranging the logistics channel in the equipment room area outside the end gate of the platform in step (5) is as follows: a straight transport channel is set up in the platform equipment area near the track area outside the platform end screen door, and the original maintenance zone between the side wall of the equipment room and the tunnel wall is uniformly designated as a "freight passage zone". Yellow guide lines and LED indicator lights are arranged along the inner side of the channel, and foldable guardrails are set on the outer side, which not only limits the flow of goods but also facilitates equipment maintenance.

[0168] A dedicated vertical freight elevator is embedded at the end of the passageway. The elevator shaft utilizes the existing column spacing in the equipment room, and the car opening is flush with the passageway to avoid sill protrusions. A call button, load indicator, and RFID reader are installed next to the elevator entrance; the elevator automatically identifies and starts when the storage cage is in place. Positioning pins are pre-installed inside the car to ensure the cage does not shift during lifting. A continuous lighting strip is added above the passageway, and reflective warning stickers are affixed to the corners. Rubber buffer strips are embedded in the floor every two meters to protect the equipment cabinet columns and the sides of the storage cages.

[0169] Furthermore, the basic structure of the vertical cargo passage between station levels in step (6) is as follows: The passage is located in the equipment area of ​​the platform level, sharing the same vertical shaft with the corresponding position on the concourse level. I-beam guide rails are embedded at the four corners of the shaft and fixed by horizontal bracing plates welded to the side of the original column grid, avoiding any weakening or slotting of the main structure. A double-rail counterweight freight elevator is installed in the shaft, with the car opening facing the horizontal logistics passage. The side wall of the car is equipped with pluggable positioning pins to lock the storage cage. The pit depth at the lower end of the shaft is reserved for maintenance space, and the upper car top is separated from the concourse ceiling by a dustproof net cover. All cables, lighting, and fire protection pipelines are laid in a dedicated channel on the rear wall of the shaft, and an inspection and maintenance access door is installed at the top of the concourse level to ensure safety during later maintenance.

[0170] Furthermore, the specific calculation method for the configuration parameters of the vertical cargo passage between station levels in step (6) is as follows:

[0171] (1) Determine the net dimensions inside the car, as shown in the following expression:

[0172] B = W c +2Δ c D=L c +Δ c H=H c +1000 (16)

[0173] In the formula, B, D, and H represent the net width, depth, and height of the freight elevator, respectively; L c W c H c These are the length, width, and height of the subway freight storage cage, respectively; △ c The minimum safety clearance for both the lateral and longitudinal directions is typically 200–370 mm.

[0174] (2) Determine the rated load Q of the vertical channel e The expression is as follows:

[0175] Q e =k s ×(Q n +M c (17)

[0176] In the formula, Q n The maximum set loading mass load for a single storage cage; M c For cage weight; k s =1.3 is the safety factor.

[0177] (3) The car lifting speed v can be inferred from the stopping window Δt(s), and the expression is as follows:

[0178]

[0179] In the formula, h is the height from the platform to the concourse level (m); t lift Δt is the elevator car lifting time; Δt is the total train stop window time; t 装卸 For horizontal push time; t 启停缓冲 The buffer time for car start-stop is 20-25 seconds in total; when h = 6m and Δt = 60s, v ≤ 0.4m / s is taken.

[0180] (4) Determine the drive motor power P and the brake force F. b The expression is as follows:

[0181]

[0182] F b ≥τ×(Q e +0.5M s )×g ​​(20)

[0183] In the formula, P is the power required by the elevator drive motor; Q e The elevator's rated load capacity is denoted by v; the elevator's lifting speed is denoted by σ; the unit conversion factor is used to convert Newton-meter-seconds to kilowatts; η is the overall efficiency, typically ranging from 0.75 to 0.8; M s τ is the self-weight of the elevator guide rail / car system; τ is the safety factor, which ensures that the braking capacity has sufficient margin under various working conditions, and is generally taken as 1.2.

[0184] Furthermore, the cargo handling process in step (7) can be specifically divided into the following three types:

[0185] Process 1: Self-pickup in the station hall. After the storage cage arrives at the equipment area on the station hall floor via the freight elevator, the escort personnel push the cage along the existing road in the equipment area, pass through the partition door of the station hall equipment area to enter the passenger platform service area. Several smart self-pickup lockers are set up in the non-paid areas of the station hall (such as entrance and exit passages, ticket areas, etc.). The escort personnel store the goods in the self-pickup lockers in the station. After successful RFID matching, the goods are delivered to the lockers and the empty cage is retrieved.

[0186] Procedure 2: Entrance / Exit Transfer Elevator. Self-service lockers are located on the ground outside the station. Storage cages are escorted through partition doors along the station hall passage to the nearest station entrance / exit. They are then lifted to the ground platform via an installed vertical freight elevator. The escorting personnel load the goods into the self-service lockers or specially designated kiosks near the subway station entrance / exit, and then return to the station hall with the empty cages via the freight elevator.

[0187] Process 3: Direct access from equipment area to ground. A vertical freight elevator will be added to the equipment area of ​​the station hall, leading directly to the ground. The cage will not enter the passenger platform, but will be moved a certain distance on the same floor of the equipment area before being directly raised to the ground logistics distribution point. Goods will be picked up by ground delivery vehicles or express delivery riders, and empty cages will be recovered with the elevator.

[0188] Furthermore, the specific method for planning the cargo movement path in the station hall in step (7) is as follows:

[0189] The station hall is gridded, and the equipment area exit P is defined. S With target node P t (Self-service lockers, vertical freight elevators, or ground delivery points). Planning cost function:

[0190]

[0191] In the formula, C(P) is the total cost of path P; d i Let θ be the length of the i-th straight path segment; i Let be the i-th turn in the path; z is the degree of overlap with passenger flow; α2, β2, and γ2 are the weight coefficients of each factor, where α2 < β2 < γ2 indicates that the cost of turning and conflict with passenger flow is higher than that of straight segments, encouraging short and straight paths that avoid densely populated areas.

[0192] A*-Lite search is used to output three shortest feasible paths and avoid high-traffic areas online. For modes two and three, a vertical distance h is added to the path endpoint. c The total time expression is as follows:

[0193]

[0194] In the formula, T c v represents the total handling time. push The speed at which the storage cage is manually pushed; h c The vertical distance to the endpoint; vlift To increase the speed of the elevator; t 启停缓冲 The buffer time for system response and start / stop is usually set to 7 to 10 seconds.

[0195] Furthermore, the specific method for arranging the station's cargo entry and exit channels in step (7) is as follows:

[0196] Openable partition doors are installed at the boundary between the equipment area and the passenger area, with infrared beam detectors embedded in the door frames to ensure passenger isolation. A "freight transport zone" is marked on the right side of the main passageway in the station hall, with low-back roller rails laid and marked with yellow guide lines. Steel plates are used to cross escalator and staircase joints. Vertical freight elevator shafts leading to the ground are arranged at the entrance and exit passages and guardrails are added. Self-service lockers or kiosks on the ground side should be located within a 10-meter radius of the station entrance and exit.

[0197] Example

[0198] A rapid loading and unloading system and construction method for bulk goods in subway stations includes the following steps: S1, designing the overall structure of subway freight vehicles.

[0199] Subway freight cars (i.e., freight carriages) are modified from standard subway train carriages, including basic structures such as the car body shell, chassis, and bogies. The doors employ a sliding mechanism that folds away from the sealing surface for storage; the door body is composed of a high-rigidity frame and lightweight composite panels. For example... Figure 2 As shown, the vehicle's floor height is no different from the platform height, and the top profile continues the standard clearance, facilitating coordinated configuration with facilities such as platform screen doors, tunnel sections, and overhead contact lines. Each door is equipped with an expansion-type sealing ring around its perimeter, achieving a tight seal through inflation when closed. The vehicle chassis adopts a box-beam structure, with a pre-reserved standardized roller rail interface for easy docking with the platform roller system, reducing vibration and impact during cargo handling. The bogies feature a secondary air spring damping structure. The control system links train positioning and coupler locking; cargo doors are only allowed to open after the train has come to a precise stop and the coupling lock is confirmed, maintaining a locked state under normal conditions. The vehicle ends are equipped with a fully automatic three-channel dense formation coupler, integrating mechanical locking, air braking, and electrical signal interfaces, and featuring micro-displacement compensation, allowing direct operation with metro passenger trains.

[0200] S2, Design the interior space layout of subway freight cars

[0201] The interior of the freight car is rationally divided into several functional areas. Positioning grooves are set along the length of the car floor, and each groove is equipped with guide rollers and quick-release latches at its bottom to guide and secure the freight storage cages. The interior space preferably adopts a matrix layout, divided into three sections, each capable of accommodating 2 rows × 3 columns, totaling 6 standard cargo storage cage units, such as... Figure 3As shown. To make full use of the height space of the carriage, a tiered shelving or hook system is designed inside. Foldable shelves are provided on the side walls and top of the carriage for placing small packages or stackable boxes, achieving a "smaller on top, larger on bottom" tiered storage mode. Foldable seats are partially installed along the side walls of the carriage for escort personnel to use for short-term duty and emergency rest. The aisle area uses non-slip flooring and is painted with conspicuous markings to ensure the safety of personnel and manual handling equipment.

[0202] S3. Specific procedures for setting up rapid loading and unloading operations for goods at subway platforms.

[0203] Once a subway train carrying goods arrives at the station, the system efficiently completes the loading and unloading of goods according to the following steps:

[0204] Freight trains (or train formations with freight cars) pull into the designated position on the platform, and the automatic train positioning system ensures that the doors of the freight cars are precisely aligned with the passenger / freight platform screen doors (such as...). Figure 4 (As shown). After the train comes to a complete stop, it sends a positioning signal to the platform control system. Upon receiving the train positioning signal, the platform freight screen doors and the carriage doors open synchronously according to the set control parameters. During the opening process, a buzzer sounds and an indicator light illuminates to remind on-site personnel to pay attention to safety. Within a few seconds, the doors are fully open, forming a loading and unloading passage that connects the interior of the carriage with the platform logistics area.

[0205] Staff (or automated guided vehicles, AGVs) waiting on the platform immediately enter the carriage after the doors are fully opened, release the bottom locking device of the target storage cage, and push the cage out of the carriage to the designated temporary storage area on the platform (within the warning tape area). If the cage is heavy, a hydraulic pusher can be used to assist in pushing it out smoothly. Simultaneously with unloading, goods awaiting dispatch at this station are also prepared. Empty cages of the same type or storage cages destined for the next station are already lined up in the platform's waiting area. After unloading the arriving goods, personnel immediately push the storage cages awaiting transport on the platform into the carriage in sequence. Guided by fixed tracks inside the carriage, the cage car is pushed to the designated locking point, triggering the locking mechanism to secure it. Multiple cages awaiting transport are quickly loaded in sequence, occupying the previously vacated space in the carriage. The entire unloading and loading process is carried out seamlessly like an assembly line, completing cage replacement in the shortest possible time. After confirming that all unloaded goods have been unloaded and all transported goods have been loaded, and that personnel have returned to the safety line, the operator issues the door-closing command. The freight car doors and platform screen doors close and lock simultaneously and quickly. The train then receives the departure signal, departs from the platform, and completes one round of cargo loading and unloading operations.

[0206] S4. Determine the layout and deployment procedures for warning tape in the platform logistics area.

[0207] To ensure that cargo loading and unloading operations do not interfere with passenger waiting, warning signs for logistics areas are set up on the platform to separate the work area. For example... Figure 5As shown, warning tape is placed around the designated logistics operation area on the platform. Preferably, the logistics area is located at the end of the platform near the freight platform screen doors, with the area determined based on actual needs. The specific area includes: one side near the platform edge, one side of the platform's rear wall (or equipment room wall), and both ends adjacent to the passenger passageway. The warning tape is approximately 1.2 meters high and features prominent yellow / red stripes and the words "Do Not Approach" to warn passengers to stay away. During non-operational hours, the warning tape is rolled up and concealed in a groove in the platform floor or wall, without affecting the platform's aesthetics or passageway.

[0208] When freight loading and unloading operations are required, the warning tape should be operated according to the following procedure: First, platform staff will set up the warning tape according to the predetermined plan. Then, staff will check that there are no passengers remaining in the work area and, after confirming safety, guide the entry and exit of the storage cages. Throughout the loading and unloading operation, the warning tape will remain deployed, serving as a means of crowd control and safety warning. Once the loading and unloading process is completed and the train has departed, the person in charge of the operation will confirm that there is no cargo or equipment remaining on site, and then release and lock the warning tape. The warning tape will automatically retract into its concealed slot under the action of the drive device, restoring the platform to its original state. During the deployment and retraction process, there are usually voice prompts or buzzers to remind passengers; the entire removal process is quick and safe.

[0209] S5. Planning of cargo handling routes in subway platform areas

[0210] After goods are unloaded from the train, they need to be transported a certain distance on the platform before entering the vertical transport channel within the station. According to equations (13) and (14), constraints on the goods transport path in the subway platform area are established, and the goods transport path on the platform is designed based on the shortest path principle and the passenger isolation principle. The starting point (goods unloading point) is selected at the end of the platform near the freight platform screen doors. Figure 6 As shown, a straight or smoothly curved passageway should be planned from this starting point to the platform staircase or freight elevator entrance. Considering that the width of storage cages is generally no more than 1 meter, and sufficient space is required for manual pushing, the planned passageway width should be at least 1.4 meters. One side of the path should be adjacent to the platform wall or platform screen door partition, and the other side should be separated from the passenger area by warning tape. Conspicuous signs should be placed at the start and end points of the handling path, such as "Start Point of Goods Handling Passage" and "Freight Elevator Entrance" painted on the ground, to guide workers along the designated route. To avoid affecting passengers, if the goods handling path intersects with areas that passengers may pass through due to the platform layout, temporary barriers or personnel should be set up to monitor the area.

[0211] S6. Design a structural modification plan for the platform screen doors at the end of subway stations.

[0212] The existing structure at the far end of the platform was modified to create a dedicated passage for goods. First, the original fixed partitions or glass doors at the platform end were removed, retaining only the original top beams and side walls. Then, a "side-sliding" freight door was installed at this passage location as a shielding partition at the platform end. The newly installed door uses a lightweight, high-strength metal frame and transparent composite panel combination structure, with the door opening designed to accommodate fully loaded storage cages. To achieve automatic opening and closing of the door, an integrated electric screw drive device was installed at the lintel, including a drive motor, guide rails, travel limit switches, and a door lock. The drive motor moves the screw to advance or pull back the door leaf, enabling rapid horizontal sliding opening or closing of the door; after the door closes, the lock automatically locks the door leaf, ensuring a tight seal at all times.

[0213] Next, the end door control module is connected to the platform PLC and the train freight communication bus. The end freight door is only allowed to unlock and slide open when the train sends a freight operation instruction and the platform confirms that the main platform screen door is closed and the train end cabin door is unlocked; otherwise, it remains locked. For safety interlocking, bidirectional position sensors installed on the door transmit the door's opening and closing status to the platform control center in real time and simultaneously to the train dispatching system. If the end door is detected as not fully closed, the train will be prohibited from starting to prevent danger caused by the train moving when the passageway is open.

[0214] S7. Design of the logistics channel layout scheme for the equipment room area outside the terminal gate.

[0215] Utilizing the space in the equipment area adjacent to the tunnel wall on the outer side of the platform, a continuous horizontal cargo passage will be laid to facilitate the entry of storage cages from the platform into the vertical freight elevator. For example... Figure 7 As shown, a "freight passageway" is planned along the side wall of the platform outside the platform end door, transforming the original passageway for maintenance personnel into a freight passageway. The length of the passageway depends on the location of the vertical elevator, and the width of the passageway should be no less than 1.5 times the width of the storage cage. Considering both pushing operations and personnel walking side by side, the ideal width should be 1.5 meters. In narrow spaces, partial widening methods can be used (such as removing part of non-load-bearing walls or equipment racks to make room) to ensure passage width. The passageway floor needs to be paved with a flat and sturdy material, such as non-slip steel plates or concrete, capable of withstanding the pressure of heavy-duty freight vehicles.

[0216] A continuous yellow directional marking is installed along the inner side of the passageway (near the equipment room), with LED indicator lights at regular intervals to clearly indicate the direction of cargo movement, facilitating path identification for escort personnel and AGVs at night or in low-light conditions. Foldable metal railings are installed on the outer side of the passageway to separate the cargo passage from the adjacent equipment area, preventing cargo from veering off course and colliding with equipment. The railings are hinged and can be temporarily folded down during non-cargo operations, allowing subway maintenance personnel easy access to the equipment area for inspection. Furthermore, to enhance passageway safety, continuous lighting strips are added to the top of the passageway to ensure adequate illumination around the clock; conspicuous reflective warning stickers are affixed to corners and supports; and rubber buffer strips are embedded in the ground approximately every 2 meters to mitigate potential side impacts from storage cages, protecting the equipment cabinet pillars and cage edges from damage.

[0217] S8. Design of the vertical cargo passageway between station levels

[0218] The elevator shaft adopts a reinforced concrete cast-in-place structure or a steel structure frame system, with the inner wall sprayed with a wear-resistant and fireproof coating. The top is equipped with a dedicated smoke exhaust vent and maintenance passage, complying with subway fire prevention and maintenance regulations. The elevator control system is connected to the subway platform and concourse freight dispatching system via a dedicated PLC module, enabling real-time monitoring of car status, floor position, load, and door opening / closing status, and possessing remote fault diagnosis and emergency manual switching functions.

[0219] like Figure 8 As shown, the freight elevator is a specialized model with high load capacity and rapid start-stop performance. The internal dimensions of the car are adapted to the maximum stacking configuration of the storage cages, and the car doors open towards the horizontal passageway of the platform level. The floor is paved with non-slip and wear-resistant material and equipped with guide rail grooves to facilitate the smooth entry and exit of goods. A movable locking device, such as a pin or wedge, is installed at the bottom of the car to secure the storage cages in the center of the car after they enter, preventing them from swaying or shifting during lifting.

[0220] S9. Determine the location coordinates and functional parameters of the vertical cargo passageway between station levels.

[0221] The ideal location should meet several principles: (1) be as close as possible to the platform's cargo loading and unloading area to shorten the horizontal transport distance; (2) avoid main passenger passage areas and important structural beams and columns; and (3) have the conditions to set up cargo distribution points on the concourse level. Based on these principles, the location is determined on the station design drawing. The concourse level corresponds to the vertical coordinates, and elevator exits are opened in areas that do not affect the ticket hall and ticket gates.

[0222] Functional parameters include the elevator's load capacity, speed, and control logic. Regarding load capacity, considering the weight and batch size of the storage cages, the elevator is designed to transport at least one fully loaded cage plus additional weight per trip. Therefore, setting the elevator load capacity to twice the full load weight is a safer configuration. For speed, based on urban rail transit emergency requirements and logistics efficiency needs, a speed of 1.0 m / s or higher is selected to ensure a one-way travel time of less than 15 seconds. Simultaneously, the elevator's safety parameters include: door opening delay (ensuring the elevator stops 0.5 seconds before unlocking and opening the doors), overload alarm threshold, emergency stop delay, and restart time. These parameters can be comprehensively set according to subway operation regulations and the characteristics of freight transportation.

[0223] S10. Establish specific procedures and movement paths for cargo handling operations in the concourse level of subway stations.

[0224] Based on the actual needs of the station, select and implement a suitable cargo handover mode for the concourse level, clarify the process of cargo delivery from the concourse level to the final pickup point, and plan the corresponding movement routes. There are three main modes for cargo handover at the concourse level, which the station can choose according to its conditions:

[0225] Mode 1: In-station self-pickup locker mode. When using the in-station delivery solution, the freight elevator will deliver fully loaded storage cages to the equipment area on the station hall floor, such as... Figure 9 As shown by the solid arrow, the security personnel push the cage along the equipment area aisle to the passenger concourse. Then, they push the cage directly to the smart parcel locker installed in the non-paid area (outside the turnstiles) of the concourse along the designated passageway. After verifying that the RFID tag integrated on the cage matches the locker system information, the personnel open the cage door, remove the goods one by one, place them into the corresponding slots in the locker according to their destination, and promptly close and lock the empty cage. After delivery, the security personnel push the empty cage back and send it to the freight elevator for return retrieval. In this mode, the goods remain within the station throughout the entire process, and passengers can retrieve them from the locker themselves using a verification code. This method is suitable for use in stations in high-traffic central urban areas.

[0226] Mode 2: Station Entrance / Exit Handover Mode. If goods need to be delivered outside the station (e.g., near a subway station entrance / exit), a transfer elevator solution can be used. Similar to Mode 1, security personnel enter the passenger concourse from the station hall equipment area through a partition door, then push the storage cages along the planned cargo passage to a location not far from the nearest subway entrance / exit (usually near the entrance / exit corridor in the station hall). A vertical freight elevator is installed using the entrance / exit passage space to lift the storage cages to the ground. Once the cages reach the ground, security personnel transfer the goods from the storage cages to self-service lockers or temporary express delivery counters near the entrance / exit, where recipients can collect them outside the station; simultaneously, the empty cages re-enter the freight elevator and descend back to the station hall level. Security personnel retrieve the empty cages and return to the station hall equipment area via the original route for the next batch of goods. In this mode, goods are delivered to the ground via the subway station entrance / exit, achieving a connection between the inside and outside of the station. This is suitable for subway stations that cannot accommodate self-service lockers internally or require connection to ground delivery services.

[0227] Mode 3: Direct Ground-Level Access from Station Concourse Equipment Area. For stations with exceptionally high passenger traffic or those seeking to further expedite delivery, a dedicated freight elevator can be installed within the station concourse equipment area, directly connecting to the ground level to transport the storage cages. In this mode, escort personnel do not need to enter the station concourse's public area; they simply move the storage cages a few meters from the original freight elevator exit on the concourse level and push them into another freight elevator car that directly connects to the ground. This elevator then activates, lifting the cages along with the goods to a logistics distribution point near the ground entrance / exit. Ground delivery vehicles or couriers can immediately retrieve the items from the cages and load them for delivery. This mode bypasses the passenger flow area of ​​the station concourse, minimizing disruption to passengers and making it suitable for stations with open ground areas.

[0228] In summary, the present invention, through the solutions described in steps S1 to S10, enables subway stations to have the function of rapid loading, unloading, and handling of bulk goods. Through vehicle modification, platform renovation, and process optimization, goods can be fully utilized for transshipment within the city using the subway's off-peak capacity. Practical results show that this system can significantly improve urban distribution efficiency, alleviate surface traffic pressure, and reduce logistics costs and carbon emissions. Simultaneously, throughout the implementation process, emphasis is placed on safety isolation and coordinated control to ensure that passenger safety and operational order are not affected under passenger-freight co-operation. The above embodiments illustrate the implementation path and measures of the main content of the present invention, which can provide a reference for large-scale logistics distribution practices in Chinese cities utilizing existing subway systems.

Claims

1. A method of constructing a mass cargo handling system for a subway station, characterized by Comprise the following steps: Step (1): set the overall structure of the subway freight vehicle, internal space layout and hatch opening and closing control parameter calculation method; Step (2): configure the built-in mobile storage cage of subway freight vehicle; Step (3): configure the operation mode of the platform screen door structure of the subway freight vehicle, and the platform freight loading and unloading operation process; Step (4): design the layout scheme of the warning tape in the logistics area of the subway platform; Step (5): configure the platform layer freight handling path; Step (6): build the vertical channel for freight handling between the subway platform and the station hall; Step (7): build the station hall freight handling route and in-out station channel.

2. The method of claim 1, wherein, Step (1) specifically includes: Step (11): the overall structure of the subway freight vehicle: The structure size of the subway freight vehicle is consistent with the existing subway train, and the floor height of the subway freight vehicle is consistent with the platform. The chassis structure of the subway freight vehicle is a sandwich box-shaped main beam, and the chassis is transversely arranged with standardized mounting interfaces. The left and right sides of the vehicle body are provided with wide sliding-folding combined doors. The door structure is composed of double-layer light composite board and high-stiffness frame. The concave groove for folding door body is embedded in the inner wall of the vehicle body; Step (12): internal space layout of subway freight vehicle: The internal space of the subway freight vehicle is divided into multiple standard slots arranged along the longitudinal direction of the vehicle. The bottom of each slot is provided with a guide roller and a quick plug lock device for guiding the positioning and locking of the storage cage. The inner wall is partially provided with foldable seats, and the top is provided with a temporary installation hanging device or an embedded slide rail for transporting non-standard goods; Step (12): the calculation method of the opening and closing control parameters of the hatch of the subway freight vehicle is: In single station dwell time t s Under the metro freight scenario of not more than 60s, i.e. high-frequency stop station, the complete opening and closing time T of the hatch c As follows: In the formula, L s is the sliding stroke; θ f is the folding angle; v s is the average sliding speed; ω f is the average angular speed of folding; To ensure that the door body does not interfere with the concave cavity of the vehicle body during sliding disengagement, the expression is as follows: D r ≥D m +δ wherein D r is the depth of the receiving groove; D m is the thickness of the door leaf; δ is the assembly gap; The required thrust force F in the slip phase s The calculation formula is as follows: In the formula, T e is the motor torque; r is the screw radius; m d is the door mass; μ is the rolling friction coefficient; g is the gravitational acceleration; Power of metro freight vehicle cabin door motor P m The expression is as follows: In the formula, T m is the instantaneous output torque of the driving motor, in units of N·m; P calc is the actual required theoretical calculation power of the system during operation; ω m is the rated angular velocity of the motor; η m is the transmission efficiency; and the coefficient χ is a safety margin coefficient, with a value of 1.

2.

3. The method of claim 1, wherein, Step (2) specifically includes: Step (21): the structure of the built-in mobile storage cage of the subway freight vehicle is: The storage cage body is a load-bearing frame formed by welding high-strength aluminum alloy profiles. The frame corners are provided with stamped reinforcing angle plates and hoisting ring holes. The frame is provided with foldable grid side walls. The bottom of the storage cage is paved with wear-resistant composite board. The composite board is longitudinally arranged with polyurethane roller groups and embedded with guide racks. The rollers are connected to the bottom plate of the storage cage through spring damping seats. The bottom plate is internally arranged with four-point weighing sensor interfaces; Step (22): the calculation method of the design control parameters of the built-in mobile storage cage of the subway freight vehicle is specifically: Determine the three-dimensional reference size of the cage body, and the expression is as follows: In the formula, L c , W c , H c respectively represent the design reference dimensions of the cage in the length, width and height directions; L lim , W lim , H lim respectively represent the limit values of the cage outer dimensions in the length, width and height directions; and △ is the vehicle cargo compartment slot clearance. When the storage cage moves along the platform roller line or the vehicle roller, the pushing resistance is considered as the rolling resistance, which is specifically: F rr = μ r × (Q n + M c ) × g (6) where F rr is the rolling resistance; μ r is the rolling wheel-rail friction coefficient; Q n is the maximum set load mass load for a single storage cage; M c is the self-weight of the storage cage; To realize single-person escort or AGV (Automatic Guided Vehicle) assisted pushing, a pushing force F push The following should be satisfied: F push ≥ φF rr Wherein φ is an operation margin coefficient. Step (23): Number of storage cage rollers n w With single wheel limit load C w Satisfies the following equation: where C w is the ultimate load capacity of a single roller; P w is the actual load on each roller; and λ is the load redundancy factor.

4. The method of claim 3, wherein, The operation mode of the platform screen door structure in step (3) is specifically: The platform screen door includes a standard passenger section screen door and a passenger and freight shared section screen door. The passenger and freight shared section screen door is arranged at the two end areas of the platform and is aligned with the hatch position of the first and last subway train carriages, respectively. The width of the screen door is adapted to the effective opening face of the freight door leaf. When the freight carriage of the docking subway train is connected, the screen door is opened with the same width as the hatch of the freight carriage. When the stopped train is a pure passenger train, the screen door can also be connected with the passenger carriage hatch, and it is opened synchronously with other standard passenger section screen doors. The passenger and freight shared section shielding door adopts an electric drive sliding type one-way opening mechanism, is matched with a 24V low voltage direct current motor and a screw rod guide rail system; during opening and closing of the shielding door, its operation state is returned to a platform PLC in real time through a position sensor, and data is kept synchronous with a subway dispatching center through a signal bus.

5. The method of claim 4, wherein, Step (5) is specifically: Step (51): Discretize the accessible surface into grid nodes with the station building plane coordinate system as the reference, define the first or non-junction carriage loading and unloading port P0(x0, y0), the station end shielding door passage port P1, the equipment area entrance P2, and the vertical freight elevator car port P3; under the constraints of "not crossing the waiting area, not transversely cutting the evacuation passage, and the minimum turning radius ≥ r - {min}”, use the weighted shortest path model to plan the horizontal cargo handling path, and the expression is as follows: where d i is the length of the ith segment of the path; θ i is the angle between adjacent segments; and α1, β1are the cost weights for straight and turning, respectively, with β1> α1to discourage frequent turning; and n is the number of segments in the path. Step (52): The path search adopts A* algorithm, and the Euclidean distance is taken as the heuristic function After obtaining the node sequence {P0, P1, P2, P3}, the straight line and the circular arc between the nodes are smoothed to ensure that the turning of the storage cage does not exceed r min = 1.2 m; after completing the horizontal path, the total pushing resistance is calculated, and the expression is as follows: wherein μ r is the rolling friction coefficient; γ1is the cornering power factor; Q n is the maximum set load mass load of the storage cage; M c is the self-weight of the storage cage; Step (53): The vertical freight elevator dispatch adopts a "first-come, first-served" strategy: the elevator is called when the car is at the station hall and idle; if it is in operation, the waiting time t is calculated. w =t cycle -t elapsed Only when t w <t thr Only if a waiting period is arranged, otherwise, the passenger will be switched to another backup freight elevator; the total travel time is calculated using the following formula: In the formula, t cycle is the time of one complete cycle of elevator operation; t elapsed is the time of operation of the current cycle; t thr is a settable acceptable latency threshold; T is the total transport time for the entire path; d i is the length of the i-th section of the transport path; v push is the manual pushing speed; t w is the elevator waiting time; t lift is the freight elevator lifting time.

6. The method of claim 5, wherein, Step (6) of constructing a vertical goods carrying channel between a subway platform and a station hall is specifically: Step (61): determining the net size in the car: B = W c + 2Δ c D = L c + Δ c H = H c + 1000 (11) In the formula, B, D, H are the internal net width, depth, height of the goods elevator respectively; L c , W c , H c are the length, width, height of the subway goods storage cage respectively; Δ c is the minimum lateral and longitudinal safety clearance. Step (62): determining the vertical passage rated load Q e : Q e = k s × (Q n + M c ) (12) where Q n is the maximum set load mass load for a single storage cage; M c is the cage weight; k s is the safety factor; Step (63): the car lifting speed v is obtained according to the stop window Δt(s), and the expression is as follows: where h is the height of the landing to the mezzanine level, m; t lift is the time of the lift car to rise; At is the total window time of train stopping; t 装卸 is the horizontal pushing time; t 启停缓冲 is the car starting and stopping buffer; Step (64): Determining the elevator drive motor power P and the brake braking force F b The expression is as follows: F b ≥τ×(Q e +0.5M s )×g (15) where P is the power required by the elevator drive motor; Q e is the elevator rated load; and σ is a unit conversion factor. η is the overall efficiency; M s is the weight of the elevator guide rail / car system; τ is the safety factor.

7. The method of claim 6, wherein, Step (7) of constructing a station hall goods carrying route and an in-out station channel includes a station hall self-pickup mode, an entrance and exit transfer elevator mode and a direct ground mode in the equipment area, and is specifically: Mesh the station hall floor, define equipment zone exit P S With target node P t , Plan cost function: where C(P) is the total cost of path P; d i is the length of the i-th straight path segment; θ i is the i-th corner in the path; z is the degree of weaving with passenger flow; and α2, β2, γ2 are weight coefficients of various factors, where α2< β2< γ2 indicates that the cost weights of turning and conflict with passenger flow are higher than those of straight segments. The A*-Lite search is adopted, three shortest feasible paths are output, and passenger flow hot areas are avoided online; for the exit and entrance transfer elevator mode and the equipment area direct ground mode, a vertical distance h is added at the path end point c The total time expression is as follows: In the formula, T c is the total handling time; v push is the manual pushing speed of the storage cage; h c is the vertical distance of the end position; v lift is the elevator lifting speed; t 启停缓冲 is the system response and start-stop buffer time.

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