Vehicle Movement Control System for Railroad Terminals

This invention relates to a vehicle movement control system for use in railroad terminals. More particularly, my invention relates to a remote control arrangement by which movement of all vehicles and operations of remote mobile work units, for example, switching locomotives, are directed and controlled from a central control headquarters in a railroad terminal area.

Railroad terminals designed particularly for freight train operations normally consist of receiving and departure yards, one or more classification yards, various servicing facilities for locomotives, cabooses, and freight cars, and industrial yards and tracks for serving local customers. Also included are various control headquarters and offices, mobile work units or crews, and communication facilities connecting all such locations and units in order to provide management control or supervision of the operations. Control systems for classification yards are already known in the railroad art and include such features as automatic switching systems for routing the cuts of cars to preselected storage tracks and automatic speed control apparatus for obtaining the proper coupling speeds between cars as they arrive at their selected storage location. Further, interlocking control systems for the entrance and exit switching matrices to a terminal area and for individual yard entrances are also known, including the remote control of such interlocking systems. However, many manual operations are still involved in the usual railroad terminal area. These include the delivery of written operational and work orders to switching crews and manually recording the operations performed and the movement of cars between yard locations to maintain a car location inventory. Further, each switching crew foreman controlling a switching locomotive in the various yards or serving nearby industries decides what procedure to follow, that is, the order of specific operations in moving cars. Also such crews must frequently return with their locomotives to a central location to receive subsequent orders for moving vehicles throughout the area. Obviously, this form of operations control does not result in the most efficient or economical order for the work items performed or the most efficient use of the facilities available. The manual procedures frequently require additional manpower and extra movements of the various locomotives and other type work units. This reduced efficiency and economy in the operations also adds to the total amount of apparatus actually needed, particularly locomotives for switching purposes. Improvement in efficiency and economy of terminal operations may be obtained if all vehicle movements are controlled and directed from one central location and specific work assignments are transmitted directly to the various mobile work units scattered throughout the area.

Accordingly, an object of my invention is a centralized vehicle movement control system for railroad terminal installations.

Another object of my invention is to provide within a railroad terminal control system a centralized vehicle movement control arrangement.

Also an object of this invention is a vehicle movement control system for railroad terminals in which a central data processing means selects and transmits specific work commands to remote mobile work units within the terminal area.

A further object of this invention is a method of controlling the operations of mobile work units in a railroad terminal area by selecting and transmitting itemized work command formats from a central data processing means at the control location to selected mobile units which perform the desired operations and by checking the correct performance of the assigned work by the vehicle movement information periodically reported to the central data processing means from the remote locations.

Still another object of the invention is a vehicle movement control system for railroad terminals in which a work assignment selected by a movement controller is translated into an itemized work format by a data processing means and transmitted to a selected remote mobile work unit where it is recorded in printed form as instructions to the work unit crew.

It is also an object of my invention to provide a method and apparatus for controlling the movement of cars in a railroad terminal area by which an itemized work list for efficiently accomplishing a series of desired car movements is determined by a central process control means and transmitted to a selected switching locomotive, which completes each work item in order as the necessary track routes are successively established by remote control by the central process control means in response to information transmitted from the switching locomotive as each item is completed and checked for correctness by the central process control means.

Another object of my invention is an arrangement for controlling the movement of cars in a railroad terminal area including a central data processing control means, switching locomotives with data recording and transmission devices, a terminal communication system, and track route control apparatus wherein the central processing means translates desired car movements into a series of work items which are transmitted as a printed itemized format to the selected switching locomotive whose crew performs each work item in listed order, reporting completion of each item to the central processing means, which checks the correctness of the completed work and responds by transmitting a route control to position wayside apparatus to establish the track route required for the next work movement if the previous work has been correctly performed.

Other objects, features, and advantages of my invention will become apparent from the following description when taken in connection with the accompanying drawings and appended claims.

In practicing my invention, I add the novel vehicle movement control arrangement to the automatic control system provided for classification yards in a railroad terminal area. Such class yard control systems normally include a central data processing means, automatic speed control apparatus for obtaining proper car coupling speeds, and an automatic switching system for routing cars to the desired storage tracks. The automatic speed control and switching apparatus is controlled by the central processing means which includes a computer portion programmed for determining the leaving speed for the various cars from the car retarders in accordance with the car parameters previously measured and recorded. As part of the yard control operations arrangement, an inventory by serial number of the cars occupying the storage tracks of the yard is also maintained by the data processing means with the car numbers recorded by any known kind of manual or automatic car identification system. Various parameters of the classified cars, such as length, number of wheels, and weight, are also stored in the data processing arrangement. This type of yard control system is already known in the art in several different specific forms.

To all of this, I add a movement control center with input/output means associated with the central data processing means in order to read out car and locomotive location information and for input of designated work assignments, such as vehicle movements, to be accomplished in the terminal area. I also add to the existing communication system a digital arrangement having a data transmission capability. This involves, of course, adding such a capability over whatever radio communication channels are already in use to contact the various types of remote mobile work units and personnel scattered throughout the terminal area. Further, each such mobile work unit, for example, a switching locomotive and crew, is provided with digital and voice communication apparatus to receive and transmit data and voice messages. The incoming data is recorded by a printer device aboard the work unit or locomotive as an itemized work command to the work unit foreman. The transmitter for returning information to the central location is part of a portable communication device provided for the foreman, conductor, or chief of the work crew. This individual carries the portable unit providing two-way voice and data transmission communications with the movement control headquarters and with the central processing unit.

The input of the work assignment or vehicle movement command into the central processing unit activates the preparation of a work list format which is transmitted to the selected mobile work unit which may best accomplish the work assignment. The work command format is an item-by-item list in the sequential order that is to be followed in performing the assigned task. If vehicle movements are involved, for example, the switching of railroad cars, the format lists in order the movements that are to be made by the switching locomotive to complete the assignment in the most efficient and economical manner. The foreman of the mobile work unit transmits a signal to the central processing unit as each item of the work list is completed. If a vehicle movement is involved in one of the yards of the terminal, the processing unit transmits control functions to establish the required track route, each new set of control functions being transmitted as the previous item on the work list is completed and so reported. When movement of cars is involved, such movement is automatically detected and reported from the various field locations by apparatus supplied throughout the yard and is recorded in the processing unit as information functions are received. The reception of such information enables the central processing unit, using previously stored car parameter data, the car inventory, and the received work completed reports, to check that each work list item has been done correctly. If there is any inconsistency between the assigned vehicle movements and those reported and correlated with the stored inventory, a new route can not be established until the inconsistency or error is corrected. The necessary corrective action is determined and instructions transmitted to the locomotive and crew involved. The work unit foreman also has voice communication with the movement direction center to enable exceptions to routine operations to be quickly handled. The information reported into the central processing means is also available for readout to movement direction headquarters to follow and check progress throughout the terminal area when exceptions occur and upon completion of assigned tasks.

I shall now describe in more specific detail a railroad terminal vehicle movement control system embodying one form of my invention, referring from time to time to the accompanying drawings in which:

FIG. 1 is a diagrammatic illustration, in conventional block form, of a type of railroad terminal control system which may embody this invention.

FIG. 2 is a partially diagrammatic, partially schematic illustration of a vehicle movement control arrangement embodying my invention as applied to a specific yard portion of the terminal control system illustrated in FIG. 1.

FIGS. 3A to 3C, when placed adjacent vertically in order, are a macro flow chart for the vehicle movement control process provided by my invention.

In each figure of the drawings, as appropriate, similar reference characters designate similar parts or portions of the apparatus and/or systems.

I shall refer first to FIG. 1, which shows the overall system for controlling the operations of a large railroad terminal area. A conventional block at the top of this drawing figure represents, as is marked, the terminal headquarters. This is one of five major personnel groups or control locations within the terminal control system. The other four major locations, each outlined by a conventional block, comprise the Movement Control Center (MCC) shown below the terminal headquarters, the Facilities Service Center (FSC) and the Industrial Service Center (ISC) shown to the left and right, respectively, of the MCC location, and the Communication Service Center (CSC) shown below the Movement Control Center.

Another important element of the terminal control system is the data processing means, elements of which are grouped to the right of the Communication Service Center within a conventional dot-dash block designated as the Data Processing Center. These elements comprise a central data processing unit, labeled and hereafter referred to as the CPU, together with an associated program input/output (I/O) device and a data file or storage unit, all shown by conventional blocks. The central data processing unit CPU consists of the digital computer element which was previously mentioned as controlling the automatic switching and the speed control systems used in the classification yard to control the proper routing and correct coupling speed for classifying cars. During classification operations, data concerning car locations, i.e., inventory and car identification, both as to serial numbers and car parameters, is produced, correlated, and entered by the CPU into the Data File element, which represents the data storage capability of the data processing center. Such stored data may be recalled as needed in other operational procedures of the CPU. It is also to be noted that a single data processing center normally services the entire terminal system for management and supervisory control procedures. This includes, as already indicated, such data processing and computer procedures as needed for classification yard operations, for which priority interrupt type of input/output for data and controls is used. The CPU is further defined as any known type of on-line, real-time process control, stored program digital computer. One specific digital computer apparatus which has been used in such classification yard control systems, and which can also be used in the system here described, is the Honeywell Type DDP 516 which is manufactured by Honeywell Information Systems, Inc., Framingham, Mass. Normally, a basic machine language such as DAP-16 is used for programming.

Within the terminal headquarters block, the smaller blocks shown along the bottom represent the control console positions of the principal supervisory personnel located in that office. The center position is that of the terminal superintendent, designated SUPT, while to the left is the control position occupied by the main line train dispatcher (DISP) and to the right is the position occupied by the chief clerk and his assistants and designated as the CLERK position. Each control console position shown within the terminal headquarters is provided with access to the voice channels of the terminal communication system in order that such communication may be available with all parts of the terminal system and to various remotely located offices and other headquarters. This voice channel access is indicated at the left of each control console block by an appropriate symbol which is associated with the single line representation of the voice communications arrangement. This single line representation of the voice channels is designated throughout the drawings by an associated small circle with a letter V insert. Each control console position is also supplied with an input/output (I/O) or output only visual device which is used for a readout display of information essential to the operations controlled or supervised by that set of management personnel or for the input of control functions or command directives relative to that level of supervision. While any type of input/output display means appropriate to the operation may be used, a well-known type is the cathode ray tube (CRT) display device, with associated input keyboards, which can be used for the display of requested data or operational information and for the input of commands and other data. A specific CRT system which may be used, and which is compatible with the previously cited Honeywell computer, is manufactured by Computer Communications, Inc. All such data for display or for input is transmitted to and from the CPU in the Data Processing Center over digital communication links which are shown in the drawing by a single line representation further designated by a small square with the letter D insert. These input/output display devices are capable of providing a readout of the existing conditions throughout the terminal or of stored information and directions being given by other personnel, while the input may consist of desired actions, orders, or information for data storage. In some cases a hard copy record is essential for long reports and messages. For this purpose, a line printer may be required at the terminal headquarters in addition to input/output typewriters at some other locations. The terminal headquarters device for this purpose is designated by the smaller conventional block in the upper right of the terminal headquarters block. Such devices are also under the direct control of the CPU by direct digital link channels over which is transmitted the necessary information to provide such hard copy.

The Communication Service Center functions to provide communication channels between all elements of the terminal system and to various other headquarters and external locations. Switching is provided, normally automatically, for common user circuits for the transmission of digital data and voice communications. As required, this center also supplies recording, editing, and retransmission of messages and other types of recorded data. The communication service, as indicated, is not limited to the terminal area but will include channels or message service to customers, to interchange railroads, to satellite locations, and to the central operations headquarters of the entire railroad, designated by the block in the lower right. This external service in particular may be provided by various types of channels, such as wire telephone or teletype and both voice and high speed digital data transmission radio, including microwave channels. Of particular interest in the present discussion are the voice channels and digital data links established between the MCC and the CPU, respectively, and the mobile work forces employed throughout the terminal area, such as switching locomotives, repair crews, and other field service elements, all designated by the conventional block in the lower left of the drawing.

The Facilities Service Center is responsible for car and motive power servicing and repairs, for maintenance and servicing of all terminal facilities, and for similar functions. Communications, both digital and voice, are required for this center to various repair and maintenance crews, service shops, and similar locations. This FSC is provided with a control console which includes voice communication means and an input/output display device with digital link to the CPU. The Industrial Service Center is responsible for customer contacts and facilities and for initiating the pickup from, and delivery of cars to, industry tracks. The ISC also maintains an inventory of cars in industrial sidings within the terminal area jurisdiction. Obviously, this center also needs voice and digital communication to many places and is provided with a control console having a voice communication means and an input/output display device. Both of these service centers have representatives at the movement control center who also are provided with control consoles designated here by the left and right console symbols within the movement control center block, designated FSR and ISR, respectively. These representatives provide coordination between the service centers and immediate contact with the movement director for exceptional operations.

The movement control center also includes the movement director and such assistants as are necessary. A single control position is shown in this figure with the console symbol designated by the reference MD. Each element in the movement control center, including the FSR and ISR, is provided with communication means with access to the entire communication system, designated by the symbols showing the voice channel communication means and by the input/output display devices with digital links to the CPU. All of the input/output display devices will be of the same type throughout a particular system such as the cathode ray tube type previously mentioned. In the facilities and industrial service centers, the MCC, and the terminal headquarters, the digital communication links terminating in the input/output display devices provide direct access only into the CPU for input and readout of data. Data transmission to external locations and to terminal mobile work units is direct from the CPU over common user digital links switched by the CSC. Direct voice communication between the centralized locations such as the FSC, ISC, MCC, and the terminal headquarters is normally by intercommunication channels providing a direct link between such elements not requiring switching at the communication service center. However, the voice communication means on each control console also provide common user access through the communication center to locations external to the yard and to the mobile work units.

The final conventional block representing one of the centralized terminal control locations, that is, those blocks shown above the communication service center is that designated as FACILITY. This block represents all service and maintenance locations or shops handling such things as motive power, cars, cabooses, and track and wayside apparatus maintenance. It is to be noted that it is tied into the direct voice channels including the intercommunication arrangement for the centralized elements and is also tied into the digital link channels for direct access to the CPU from its input/output display device.

Since my invention is directed to the control of vehicle movements within the terminal area, a specific example of this type of control has been extracted from the overall system shown in FIG. 1 and is illustrated in FIG. 2, to which I now refer. At the top in this figure is shown diagrammatically an expanded movement control center MCC with two directly related operating facilities. An operating position or control console is illustrated for the movement director (MD), the facilities service representative (FSR), the industrial service representative (ISR), and one assistant movement director (AMD). The MD console is a master unit and is here shown with three input/output display devices. Typical information displays which may be entered into some of the devices are shown by the conventional blocks connected by dotted lines and consist of such items as the terminal schedule and individual train details. This console may have other devices for access to information readout in other forms. Smaller control consoles are indicated for the FSR, AMD, and ISR, each with a single input/output display device. Typical information which may be displayed on the FSR device is that pertaining to motive power availability, as conventionally indicated, while the ISR display device will normally show information concerning the industrial service center activity such as industry requests or car locations. The display device for the assistant movement director AMD will display items similar to those on the master MD console but at any one time will display that data associated with the specific duty to which the assistant is assigned. Each of these control console positions is, of course, provided with voice communication means, with access both to the intercommunication arrangement and to external communication facilities.

A large display model of the entire terminal area is illustrated as being located within the movement control center for display of general information and indications for an overall picture of the terminal operations. This model receives information only for display purposes, that is, readout only, as there is no associated input device. The specific details, of course, of the overall display illustration are extracted to the individual console display devices as the personnel handle particular problems occurring during terminal operations. As examples, two of the facilities associated with the operations of, but not in the same office location as, the MCC are shown, the mainline dispatcher (DISP) and the crew calling center (CC). Each has an operating console and the necessary communication facilities, both digital and voice. Typical information displays received from the CPU are indicated, i.e., the mainline dispatcher device displaying necessary mainline scheduling and that of the crew caller, the available crew information. The mainline dispatcher also has other control means and communications, for controlling the movement of trains on the mainline, which are not shown as they do not enter into the terminal operations here considered.

Also shown by conventional blocks are the central processing unit CPU and the communication service center CSC. Each serves the same purpose as that described for FIG. 1 but the communication links here shown are limited to those associated with the vehicle movement control arrangement. At the right, the CPU is shown with direct digital input and output links with the consoles of the various elements of the movement control center and directly related locations. The communication service center CSC provides common user type voice and digital data communication facilities between the movement control center and the CPU, respectively, and mobile work units involved in the yard or terminal operations. However, a separate direct digital transmission system is provided to the field logic units for remote control of track apparatus, such as track switches, and for the reception of indications from such wayside apparatus as car or wheel counters, train detectors, switch position indicators, and similar elements. Such remote control systems are well known and specific details are not necessary. Depending upon the desired transmission rate, the remote control system may be either a Time Code Control System (e.g., Type L, Form 514) or a Solid State Code Control System (e.g., Type 560) manufactured by the Union Switch & Signal Division, Westinghouse Air Brake Company, Swissvale, Pa., applicant's assignee. It may be noted that a local control panel is also provided with direct connections to the field logic units so that individual wayside control of such items as track switches may be exercised when necessary for purposes of exceptional type operations.

The lower part of FIG. 2 schematically illustrates portions of two yards of the terminal system and two switching locomotives working in various parts of the terminal. At the lower right are shown the remote ends, that is, distant from the hump, of a few of the bowl or storage tracks of the classification yard, each designated for reference purposes by a track number prefixed by the symbol B. The blocks shown on three of these tracks represent stored cars, the number of cars being that indicated by the number within the block. At the lower left are shown three tracks of the departure yard, designated in a conventional manner by the letter D preceding a two-digit number, such as track DO1 on which the switching locomotive is shown. Various lead tracks used for switching purposes are shown, designated by the letter L and a two-digit number, and a single caboose storage track CO1. Various switches and crossovers for establishing routes throughout the track network are illustrated, the crossovers being designated by an X and by a two-digit number reference. As previously mentioned, these switches and crossovers are controlled by the CPU through a direct digital communication system which provides for a remote control arrangement of all switches and interlocking arrangements within the yard. Also previously mentioned was the fact that indications of the switch positions and train occupancy of various detector track sections are returned by the same communication system to the CPU.

The switching locomotive SWl is illustrated sybolically as occupying or located on track DO1. Its crew is shown also by conventional symbols, the switching foreman SWF and the other crew members by the single symbol SWC. A second switching locomotive SW2 is illustrated as being elsewhere in the terminal area. For example, it may be working in the humping area, serving various industry tracks, or in the receiving yard. It may, of course, be also working in the departure yard area assembling outgoing trains. Each such locomotive within the terminal area is equipped with a data receiver and printout device, shown by the conventional block P within each SW symbol, connected by a digital communication link with the CPU. Such communication, of course, requires a radio channel since these are mobile units and obviously can not be connected by a fixed arrangement. Any one of several commercially available receiver-printer devices which is compatible with the specific digital communication channel provided may be used. One such device usable for this purpose is the radioteleprinter manufactured by Kleinschmidt Division of SCM Corporation, Deerfield, Illinois. The digital receiver and recording device provides printed work assignments and other instructions for the switching locomotive crew, illustrated by the WORK LIST block associated with each printer P.

The crew for each locomotive is interconnected by a voice communication channel, obviously short range radio. The switching foreman SWF is also linked by a voice channel with the movement control center and by a digital two-way communication link with the CPU. Each of these is part of the common user network switched through the CSC. A typical control console available to, or preferably carried by the foreman SWF is shown at the left for illustration purposes. This console contains a green and a yellow indication light, indicated as G and Y, respectively, an acknowledging pushbutton designated T, and three function transmission buttons 1, 2, and 3 for signaling the CPU that various elements of a work list, to be discussed shortly, have been completed. The operation of any one of these function pushbuttons on the foreman's console initiates the transmission over the digital communication link of the corresponding message to the CPU. The message is also identified as to its origin or transmitter location, for example, as coming from the crew of switching locomotive SW1. Also shown is a digital link between switching foreman SWF anad switching locomotive SW1. This is a remote locomotive control system by which the locomotive movements may be controlled by the foreman from any position off the locomotive or even when on the locomotive, if so desired. Such a system functions without any manual control operations on the locomotive and may be any typical system of this type. One example is shown in U.S. Pat. No. 3,096,056, issued July 2, 1963 to L. R. Allison for a Locomotive Remote Control System. It should be noted that this remote control of the locomotive is not effected through the SWF console shown. Rather, other control apparatus, not shown, is provided for this separate and distinct control system.

Before describing the operation of the vehicle movement control system, I shall briefly discuss the chart shown in FIGS. 3A to 3C. When FIGS. 3A, 3B, and 3C, in order, are placed adjacent in vertical column, with FIG. 3A at the top, a macro flow chart of the vehicle movement control process is formed, the links between the adjacent figures being designated by the circled letters X and Y. Conventional symbols are used and the other circled letters A and B designate points of entry or departure for repeat actions. This macro flow chart is illustrated in very general terms since, as mentioned, various models of digital computers are usable in the terminal control system. The illustrated chart does not provide the instructions from which more detailed flow charts may be developed in accordance with the specific computer being used in any one installation.

A typical movement control action using the apparatus illustrated in FIG. 2 will now be described, with reference also to the macro flow chart of FIGS. 3A to 3C. The assumption is that a new shift has come on duty in the movement control center to continue the usual 24 hour operation. In addition to the briefing given to each individual reporting for duty by the outgoing corresponding individual, observation of the terminal model will show the movement director the general status of the terminal area, location of the switching locomotives and approaching trains, and any potential trouble spots. A visual display readout of the current terminal schedule will enable him to plan overall movements for his shift and even for part of the next shift and to determine which must be done immediately. A visual display of train details is also available to enable him to initiate action, as will be discussed. If necessary, he may obtain additional visual information or talk with other personnel or facilities. Whenever the movement director MD initiates any action, the CPU will inform the mainline dispatcher (DISP) of any effect on the mainline scheduling, the crew clerk (CC) when and what crews are to be called, the facilities service representative (FSR) of motive power needs and other items, the industrial service representative (ISR) of effects on industrial requirements or plans, and finally the selected switching locomotive of the work assignment by a work list printout in a manner to be described. Conversely, each of these individuals or units is responsible for inputting information pertaining to their assignments to keep the CPU data file current and for informing the movement director of exceptional conditions.

It is assumed that the oncoming movement director now requests a terminal schedule display. At his input request, this display appears on one of his display devices, as conventionally illustrated, by digital transmission from the CPU, and will take the form shown by the partial example of such a schedule in the following chart.

The terminal schedule when visibly displaced shows the movement director the scheduled arrival, departure, and makeup times for trains, and the type loads (MIX), track assignment, and exceptions, in order of the earliest time involved. It may be noted that, for convenience, the 24-hour clock method of showing time is employed. The make-up time is determined by the CPU program in accordance with cut-off time for cars and estimated switching times. For non-scheduled (NS) trains, the make-up time may be established when the associated bowl tracks of the class yard become full or enough cars to make up the train are otherwise available, as in the illustrated example for train UPD. The movement director, of course, can change the make-up time as necessary to suit his overall plans. In the illustrated example, train MT is ready for departure and train DT is in departure status. These trains thus require no action by the oncoming movement director. However, from the terminal schedule and other available information, this movement director can plan ahead to determine whether or not additional switch locomotive crews, inspectors, and other personnel may be needed. He can see that trains 1NP and UPD will require immediate action in view of their programmed make-up times. He will thus visually display on one of his devices their train details.

Upon the request of the movement director, initiated on the input panel on one of his display devices, the CPU will furnish over the digital link the details for outgoing train 1NP as shown in the following chart.

The train detail display for departing trains will show the departure time, the MIX, and the block code or TAG for cars to be included in that particular train. The number (Q) and total length and weight of cars of the various selected block tags in each track or inbound train within the terminal area is also indicated. Make-up information for the train is developed by the CPU as shown in the final column of the train detail display. Train 1NP scheduled to depart at 1100 hours carries all types of traffic, blocked in the order of tags 300 and 270, with the train to be filled to 115 cars with cars of tag 090 on the rear. As previously indicated in the terminal schedule, there is a cut-off time for this train of 0800 hours. Since there are already enough cars as shown in the train detail display in the bowl tracks of the classification yard to assemble this train, the CPU program supplies the make-up plan to pull in succession 32 cars from bowl track B30, 48 cars from bowl track B27, and 35 cars from track B09, which will empty tracks B30 and B27 but leave 10 cars of tag 090 in track B09. The CPU program also totals the number, length, and weight of the cars to be used and specifies the number of locomotive units which will be required. This programming takes into account any restrictions on length or weight of cars or other factors which enter into the composition of the train. If the movement director agrees with the recommended make-up plan, he simply adds a departure track assignment D02, shown in parentheses in the last line of the chart, and presses the transmit button on his display device input panel which initiates the make-up actions. Alternate actions are available to the movement director in this case. For example, he might decide to increase the number of TAG 300 and TAG 270 cars by humping the cars already in receiving track A13 and eliminating or taking fewer cars of TAG 90 on the rear of the train. However, in the assumed example, the movement director has agreed with the proposed make-up plan and initiates the action by selecting a departure track as indicated in the last line of the train detail chart.

Although not specifically shown in the above illustrated details chart for train 1NP, the movement director or an assistant, knowing from the terminal model display the location of the various switching locomotives, will normally also designate the specific locomotive to perform the make-up of the train. Such selection of the switching locomotive as part of designating a work assignment is assumed in the initial input of the macro flow chart of FIG. 3A. It is specifically assumed that locomotive SW1 is selected to make up train 1NP.

Once the final decision on the make-up of the train is reached, in the specific example herein the selection of the departure yard track on which the train will be assembled and the locomotive to do the work, the CPU initiates the transmission of work commands, i.e., a work list format, to the selected switching locomotive to accomplish the train make-up assignment. This work list is transmitted over the digital communication link and is so addressed as to be received only by the selected locomotive, here switching locomotive SW1. Each locomotive has a data printout device P to receive and record in printed form the work list format, which is an item-by-item list of the sequential switching movements to accomplish the job assignment in the most economical and efficient manner. This work command sequence and the specific items thereon are developed by the CPU from the make-up program recommended and the other input programs and data storage available, including the known position of the switching locomotive selected. For the herein discussed assignment, i.e., the make-up of train 1NP, an example of the itemized work list as printed on locomotive SW1 follows.

Before considering the specific work list, it is to be noted that, within the terminal limits, the switching locomotive foreman is responsible for movement of the switching locomotive and any coupled cars. This foreman has a digital communication link with the CPU, as previously described, and voice communication specifically with the assistant movement director (AMD), with other movement control center personnel, and with other members of his switching crew. In general, the foreman takes the printed work list and when ready to make a specific movement, presses the corresponding numbered button on his console. The CPU checks that the previous moves were correctly made and then lines up the required route, if possible, and transmits a proceed command or authorizing signal which lights the green light G on the foreman's console, which he turns off by pushing the button T. The foreman then controls the switching locomotive to make the movement, preferably using the remote locomotive control system so that he may position himself to best observe the operation from a position off the locomotive. If an error had been made in executing the previous work item or the next route is tied up by other apparatus, the CPU transmits a hold or wait command which lights the yellow light Y in response to the foreman's indication of the completion of the preceding move, i.e., readiness for the next item. Under these conditions, if the error and correction instructions are not transmitted by the CPU or the route obstacle is not obvious, it may be necessary for SWF to talk to the AMD to correct the situation.

The illustrated work list for the switching operations to assemble train 1NP is a typical example of such work lists as printed on the switching locomotive for instruction to the crew. The work list shows, in the heading, the locomotive number, the radio number, and the job number, the crew, date and starting time, task description (fourth line, make-up train 1NP), and the present location of the locomotive. The rest of the work list format shows the movements to be made, in numbered sequences 1, 2, and 3, each including the next track destination, the specific route if there are alternates available, the number of cars to be pulled or set off, and the initials and serial number of the car where a cut is to be made. It is to be noted that the numbered sequence 1, 2, and 3 of the itemized movements or work operations repeats in cycles in order that a limited number of function transmission buttons may be used on the foreman's control console for transmitting the periodic reports to the CPU.

I shall now describe in somewhat more detail the centralized control of the operations of locomotive SW1 to complete the assumed job assignment of making up train 1NP on track DO2. The process may also be followed on the macro flow chart of FIGS. 3A, B, C. The immediately following action is shown at the fourth block level (from top) in FIG. 3A. The preceding description covers the portion of the chart above the present position. Foreman SWF, finding his crew ready, pushes function button No. 1 on his control console. This initiates the transmission of a ready-to-work (ready for item No. 1) signal to the CPU. The received signal is identified as coming from locomotive SW1 and the CPU, relating it to the previously assigned work list, checks the existing conditions in the work area as to occupancy by other locomotives or other possible obstacles. If all is clear, controls are transmitted over the separate digital channel to the field logic apparatus to establish a route from track DO1, where the locomotive is, to bowl track B30, taking into account the prescribed condition that the movement must utilize crossover X01 of the alternate routes available. When the route is established and the corresponding indications are received from the field logic, the CPU selectively transmits a signal to the SWF console to light the green light G. Foreman SWF, observing the green signal which he extinguishes by operating pushbutton T, controls the locomotive SW1 by his remote control system to move from its position on track D01 through crossover X01 and into track B30. The foreman also directs his crewman SWC to prepare for the pulling of 32 cars from bowl track B30 with the car bearing the serial number shown on the second line of item 1 on his work list as the most distant car. The crewman SWC checks the coupling of the various cars and possibly the air hose connections and if necessary uncouples any other cars in this bowl track beyond the 32 which are to be pulled at this time.

The foreman, with the locomotive in the bowl track prepared to pull the 32 cars, then presses the function button number 2 to transmit an indication of the completion of step No. 1 and readiness to follow with step No. 2 of the work list. The CPU makes the necessary check and transmits control functions to the field logic apparatus to line the route from track B30 to departure track D02 as directed by the work list. As locomotive SW1 backs out into track D02 pulling the cars from track B30, field detector devices will report to the CPU, by wheel count and/or other car detection information, the passage of the 32 cars along with the occupancy of the various switch detector sections. All this information is transmitted by the field logic apparatus over the direct remote control digital channel. The CPU checks the car movement indications against the inventory list previously prepared and other parameters stored as the cars were classified into that track to assure that all the cars intended are being removed from track B30. When the locomotive has completed the movement of pulling the cars, at least to clear the switch to track B27, foreman SWF presses his function button No. 3 to indicate readiness for the third item of the work list, that is, to enter bowl track B27.

The CPU checks the correct completion of item 2 prior to issuing the control functions to line the route into track B27. If too few cars or too many cars have been pulled from track B30, the detection of this error causes the CPU to transmit a signal to light the yellow lamp on the foreman's control console. This action is shown in the flow chart at the top of FIG. 3C. The normal process flow is further diverted (as shown in the chart), the errors and necessary corrections are tabulated, and a corrected work list format including these required corrections is transmitted to the locomotive, where it is received and recorded by the printer device P. Foreman SWF then controlss the locomotive and crew to make the movements directed by the corrected work list, which replaces or at least supplements the original list. Wait signals may also be caused if the next route is unavailable or is slow in being established, as shown in the flow chart in FIGS. 3A and 3B, respectively. If the reason for the yellow signal is not obvious, such as the next route occupied by another work unit, and a corrected work list is not shortly received, foreman SWF can communicate with the assistant movement director to determine what the exception is that causes a refusal of the next step. Of course, it may only be that the switch into track B27 is not cleared by the first block of cars, as the detector track means reports are received by the CPU from the field logic.

Assuming, however, that all is correct, the switch foreman's console green light G is illuminated, as soon as the track route is lined and locked, and the crew of locomotive SW1 continues with item 3. On the second line of item 3, the serial number of the most distant car of the 48 to be pulled is indicated so that the point at which the cut is made from any other cars in track B27 is known. When the 48 cars have been pulled from track B27, the existing string of 80 cars pulled into track D02, and the proper indications have been received by the CPU, transmission of the "ready for next work step" signal by operating button No. 1 of the foreman's console will actuate the CPU to issue directions to the field logic to line the route into track B09 over crossover X03, as is directed by the printed item 1 of the second cycle of the work list. The second line of work list item 1, second cycle, indicates the point at which the cut is to be made between the cars in track B09 since not all of the cars of tag 090 identity in this track are to be pulled during the make-up of this particular train.

When all the cars are pulled from the bowl tracks as directed by the work list, locomotive SW1 pulls into track D02 and all the cars are set out. The car number in the second line, item 2, second cycle of the work list designates the point at which the crew cuts off from the string of cars at the locomotive end, leaving that numbered car in track D02. In this example, all cars are left out and the car number is a check for the crew as to the lead car identity. The crew completes the preparation of the train unit to the extent required by their assigned duties. Having completed this item 2 of the second cycle of the work list, foreman SWF reports readiness to undertake the next work list item. The next three items require that locomotive SW1 will be operated out onto lead L01, back into departure track D01, and then onto lead L12. Each of these moves is made as the CPU causes the necessary route to be lined and transmits a green signal indication to the SWF control console to proceed with the next step. The last two moves, that is, items 1 and 2, third cycle, are separated so that other switching locomotives possibly working in the departure yard may also move along interfering routes, while switcher SW1 is traversing the necessary distances, in order that the work time in the yard of all switching locomotives may be used more efficiently. When work item 3, third cycle is authorized, locomotive SW1 moves into track C01 to pick up caboose No. SP852 as directed. This serial number of the caboose comes from the car inventory maintained by the CPU, which has thus determined that this is the first available caboose on this storage track. Locomotive SW1 is then operated through the fourth, three-item cycle of the work list to move onto track L11 annd back into track D02 to couple the caboose to the train and then to return into track L11.

Locomotive SW1 is then returned by the crew finally into track D01, its original position, to await further orders. Actually the next work assignment by this time may already have been transmitted from the CPU and printed out by the receiving device P on the locomotive. For example, while train 1NP was being made up, the movement director may have come to a decision as to the make-up of the next train in the terminal schedule, train UPD, and the necessary make-up program already decided and recorded in the CPU. This transmission of the next work assignment over the digital transmission channel direct to the printout device on the locomotive conserves time, allowing locomotive SW1 and its crew to remain on location and not have to return to a central point to receive the next order, nor long await the transmission of such work assignments.

During the assembly of a train, the work commands list of the necessary switching operations, such as illustrated previously, will include as necessary the setting out of any misrouted cars from the classification or bowl tracks as the blocks of cars are pulled to make up the train. This misrouting information is obtained by the CPU from the car tracking functions during humping operations and results in the recovery of such cars prior to the time that they might be inadvertently made up into a train for departure. The CPU, during the train make-up switching operations, also updates the car inventory storages for the various bowl tracks as the blocks of cars are pulled. Any up-to-date inventory is thus maintained as to cars in the classification yard which still are available to be made up into outgoing trains.

Other types of jobs, meanwhile, may be assigned to other mobile work units in the terminal area, for example, switching locomotive SW2. For such a work unit, the specific job may be the taking of cars from the industrial yard to set out on various industrial tracks serviced within the terminal area. The job list format under these conditions will include the car numbers and the industry track spotting positions at which they are to be located. It will also include the cars, by serial number, to be picked up and brought back to the yard for movement elsewhere and cars which are to be respotted along industry tracks in new positions. Locomotive SW2 may alternately be assigned to pushing a train over the hump into the classification yard. The work list will then designate the specific track number in the receiving yard from which the train is to be moved and will also designate the end cars of the block to be humped by their serial numbers. This humping movement will be controlled, similar to that described for locomotive SW1, by the CPU up to the time that the actual humping of the cars into the classification yard begins, that is, when the train is on the immediate approach to the hump location. From this point, the humping action is controlled directly and automatically over other control channels so as to obtain the optimum humping speed in accordance with the size of the cuts being released. This particular portion of the terminal area control system is not part of the present invention.

Following a humping operation, the humping locomotive crew may be directed to perform a trimming operation to correct any misroutes or to couple-up cars within a storage track which have stopped short of other cars. Misrouting occasionally occurs during classification because of the necessity of locking a particular track switch to prevent cornering of a car due to catch up by a following car. Also, due to unmeasurable variables, the speed control system does not always achieve coupling by every car classified. The operational method provided by this disclosure may also be used to direct and control this trimming operation. The track network is similar to that shown at the bottom of FIG. 2 and in fact is at the other end of the storage tracks such as B30, B28, etc. The control process for the trimming operation may be as complete as that previously described for the train make up. However, since the operation of the trimming locomotive is principally confined to move in and out of the storage tracks from a single lead track similar to track L11, certain modifications in the control process are possible without reducing the effectiveness of the operation.

The following description of a specific example of a modified control arrangement for a trimming operation is taken from the yard control system in use at the Alyth Yard of the Canadian Pacific Railroad, located at Calgary, Alberta, Canada. Upon completion of the humping of a particular train, the process control computer outputs a tabulation of misroutes which have occurred and the location of the misrouted cars. The terminal and yard controller (TYC), i.e., the operator, is informed also or has visual observation of those tracks in which cars have stopped short of preceding cars. In this specific installation, the TYC determines the necessary trimming actions and enters these into the computers as an itemized work list, using a CRT keyboard or a typewriter as an input device. In other words, he spells out the moves necessary for the trimming locomotive, i.e., the hump locomotive, to correct the misroutes and consolidate the cars in each track. This work list is printed out on selected other typewriters or output devices, and particularly at the hump crest to provide a copy to the trim locomotive crew. Further, the print out at other locations informs all concerned that the TYC has established or set up a trimming operation.

The trim locomotive crew proceeds to perform the work assignment, item by item. The computer outputs the necessary control functions, as and when required, to align switches to establish the trimming routes through the track network at the hump end of the storage tracks. The computer receives indications as to the moves made by the train locomotive, counts the cars moved, and compares the results of each move with the requirements of the corresponding item of the work assignment. The computer outputs the control functions to align the route for the next trimming step only if the movement just completed agrees with the required work. In this specific operation, there is no direct communication between the crew and the computer. The crew has a printed copy of the work list and, after performing a particular item, waits for the route required by the next step to be established. The computer also corrects the stored car inventory for each track from which misrouted cars aree removed or to which they are correctly added.

Computer program listings, in the DAP-16 language for the previously referenced Honeywell Type DPP 516 computer, to accomplish this trimming operation portion of the control process at Alyth Yard follow. ##SPC1## ##SPC2## ##SPC3## ##SPC4## ##SPC5## ##SPC6##

Job assignments selected by the movement control center may be transmitted by the CPU to other type mobile work units in the terminal area. For example, mobile car inspector teams or car repair teams provided with truck transportation may be used and directed throughout the terminal area to perform the necessary work. The work list format under such conditions indicates the locations of the cars to be inspected or repaired and if possible the nature of the work to be done. Such work units report completion of each job item prior to moving to the next item on their work list. Obviously, however, no route controls are needed for this type of mobile work units and also no actual check by the CPU is possible as to the full and correct completion of the work list items. However, when such a team is working on cars anywhere in the yard, the CPU provides the necessary route blocking for safety purposes. That is, no switching locomotive will be routed into any track where the cars are being worked upon by inspectors or repair teams. This safety function will be performed automatically in accordance with the data already stored in the CPU as the work assignments are made and transmitted.

The system of my invention thus provides an efficient control of the movement of vehicles in a railroad terminal area. All movement of mobile work units is directed from a central location where all the operating data and information pertaining to the terminal is readily available. Not only movement of the mobile units is directed but the movement of cars through the terminal including the various yards is centrally controlled. The work units, particularly the switching locomotives, do not need to return for specific work assignments to a central location but may remain in position for subsequent operations. In addition, the work list formats transmitted to such locomotives and other work units, and recorded thereon, direct the best sequence of the operations for the utmost economy. Since central direction of operation is thus provided, fewer personnel and less items of equipment are needed to perform the work. The economy and efficiency thus obtained result in a better and cheaper operation of the railroad terminal using the arrangement disclosed.

Although I have herein shown and described only a single specific embodiment of the vehicle movement control system for railroad terminals of my invention, it is to be understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.