Patent Application
20170305447
This invention relates generally to train control systems, and more specifically to a distributed solid state interlocking that includes a plurality of intelligent wayside signal devices such as track circuits, signal aspects, traffic controllers, track switch machines, automatic train stop machines, etc. An intelligent signal device makes its own determination related to the functionality and operation of the device, and continuously monitors its own state. For example, an intelligent signal determines its own aspect, and the position of its associated stop mechanism when used in transit applications. Similarly, an intelligent switch determines if the switch should be locked or not, and monitors the position and status of the switch. The intelligent wayside devices are interconnected together by a data network to detect train movements, and provide safe operation of trains through interlockings, as well as in automatic block signal controlled territory.
Solid State Interlockings (SSI), a.k.a. Electronic Interlockings, are well known and have evolved from the relay-based interlockings that are widely used at various railroads, and transit properties around the world. Typically, a solid state interlocking consists of a centralized vital processor that controls a plurality of signal peripherals, including signal aspects, track switch machines, automatic trip stop devices, and the like. The prior art employs a safety critical software logic that executes on the vital processor, and which is based either on Boolean equations that emulates conventional relay logic or, in the alternative, on a set of interlocking rules that are applied to a vital data base that describes the interlocking configuration. However, all Solid State Interlockings described in the prior art share the common characteristic of having the safety critical software logic executes on a central vital processor, which in turn controls various I/O devices that interface with office and wayside signal peripherals. Such interfaces to wayside signal apparatuses are normally implemented using copper cables from the centralized processor location to the various field locations where the signal apparatuses or peripherals are installed.
This centralized architecture employed by the prior art has a number of limitations and disadvantages. First, the implementation of a centralized interlocking configuration requires the installation of a large number of copper cables that interconnects the I/O ports of the centralized interlocking processor to the various signal peripherals at field locations. Such copper cables are expensive to furnish, install, test, and maintain. These copper installations require maintenance and protection against grounds, crosses, and other electrical faults. The Federal Railroad Administration (FRA) requires periodic testing of these cables to ensure the integrity of the signal installations. Further, copper installations are susceptible to electro-magnetic interference, and require shielding.
Second, the centralized architecture is susceptible to catastrophic failures, which normally cause a decommissioning of an entire interlocking. While there are a number of redundancy schemes that could be used to decrease the probability of such catastrophic failures, a catastrophic failure could still occur because of a common software fault, or due to external factors such as human error, grounding faults, lightening, or other electrical spikes.
Third, for a medium or a large size interlocking, the system response time is generally slower than the response time provided by a relay installation. This is mainly due to communication delays/time outs between the centralized processor & I/O boards, redundancy configurations to comply with hot standby requirements, and the I/O interfaces to the various signal peripherals. Also, slower response time occurs as a result of the processing time required for of a plurality of iterations of the entire interlocking logic software, and to implement safety features such as vital shutdown of the centralized processor.
Fourth, it is normally difficult and time consuming to design a centralized interlocking logic either by emulating relay logic circuits, or by developing a set of interlocking rules and associated vital data base. This is particularly the case for a large interlocking.
Fifth, after making a change or modification to a centralized vital interlocking logic software, it is necessary to perform extensive retesting of the interlocking functions.
The present invention addresses the limitations, and disadvantages of the prior art by employing a distributed processing configuration, by providing a physical and logical isolation between the various interlocking components, and by allocating and distributing the interlocking control logic to the various signal apparatuses.
This invention relates to train control devices, and in particular to a distributed solid state interlocking system, wherein the control logic for the interlocking resides in the various interlocking peripherals. The new solid state interlocking system does not employ centralized logic control, but rather uses a fast data network to communicate information between intelligent signal peripherals. Collectively, such intelligent signal peripherals operate as a data flow machine wherein the status of each signal device and other information are transmitted in real time to other signal devices. A state machine is then used at each signal peripheral to process data, and to control & provide the functionality of the peripheral.
Accordingly, it is an object of the current invention to provide a distributed electronic interlocking system, wherein the intelligence and functions of the interlocking is distributed and allocated to the various signal apparatuses or peripherals.
It is another object of this invention to provide an electronic interlocking system that minimizes the use of line cables. Line cable is defined in the art to include copper and/or fiber cable that relays a vital command from a centralized location to a signal peripheral in the field, transmits the status of a signal peripheral to another peripheral or to a centralized location, or interconnects two signal peripherals for the purpose of implementing a vital signal or interlocking function.
It is also an object of this invention to provide an electronic interlocking system that includes intelligent signal peripherals, and wherein it would be possible to provide new and/or enhanced functions related to such intelligent peripherals.
It is still an object of this invention to provide an electronic interlocking system that has a distributed intelligence in order to minimize the occurrence of a catastrophic failure that impacts a large section of the interlocking.
It is a further object of this invention to minimize a catastrophic failure by providing a distributed electronic interlocking system, which includes a plurality of hardware modules that are co-located in one enclosure, and are interconnected by a data network, and wherein each hardware module is dedicated for the control of a specific signal device.
It is another object of this invention to provide an electronic interlocking system, wherein a failure of the hardware and/or software that controls an intelligent signal peripheral does not impact the functionality of other signal peripherals.
It is also an object of this invention to provide an electronic interlocking system that is easy to design, install, test, and modify.
It is still an object of this invention to provide an electronic interlocking system that includes a plurality of intelligent signal peripherals, and wherein an intelligent signal peripheral is controlled by a generic controller that employs a plurality of parameters, or a vital data base.
It is also an object of this invention to provide an electronic interlocking system, that includes a plurality of intelligent signal peripherals, and wherein an intelligent signal peripheral is capable of communicating either directly, or through a Communication Based Train Control (CBTC) zone controller, with a CBTC equipped train for the purpose of integrating the interlocking system with the CBTC system.
It is another object of this invention to provide an electronic interlocking device that incorporates a Vital Change Management Process (VCMP) to handle disarrangements of an interlocking. This VCMP identifies changes and/or modifications to the vital control logic of an interlocking, or changes to the configuration of an interlocking, assess the impact of these changes on the various vital elements, and/or safety functions of the interlocking, defines the interlocking elements and/or functions that must be tested, maintains a record of the tests performed, and ensures that the interlocking is re-commissioned only after all required tests are performed, and successfully completed.
It is yet an object of this invention to provide an electronic block signal control installation that includes a plurality of intelligent signal units, wherein a signal unit includes an automatic wayside signal, its associated automatic trip stop mechanism, and track circuit.
It is also an object of this invention to provide an intelligent block signal control device that is parameterized to enable dynamic selection between alternate signal layout configurations, and wherein one of such configurations is used for tie-in purposes.
It is still an object of this invention to provide an intelligent block signal control device that is controlled by a generic controller, which employs a plurality of parameters, and/or a vital data base.
It is a further object of this invention to provide an intelligent block signal control device that incorporates a plurality of parameter sets, and wherein one of said sets is used to maintain train service during certain failures.
It is another object of this invention to provide an intelligent block signal control device, which is parameterized to enable selection between a plurality of signal layout configurations, wherein one of said configurations is associated with the removal from service of the signal ahead.
It is still an object of this invention to provide an intelligent block signal control device, which is parameterized to enable selection between a plurality of signal layout configurations, wherein one of said configurations is associated with the failure of the signal ahead.
It is a further object of this invention to provide an intelligent block signal control device, which is parameterized to enable selection between a plurality of signal layout configurations, wherein one of said configurations is associated with low adhesion conditions.
It is also an object of this invention to provide an electronic interlocking device that includes a centralized hardware module, which employs a plurality of virtual state machines that are logically isolated from each other, wherein each virtual state machine is used to control a signal device, and wherein said plurality of virtual state machines exchange data related to the statuses of associated signal devices.
It is a further object of this invention to provide an electronic interlocking system that includes a plurality of intelligent signal devices, wherein an intelligent signal device is programmed to provide protection for work zones.
It is still an object of this invention to provide an electronic interlocking system that includes a plurality of intelligent signal devices, wherein an intelligent signal device is programmed to enforce temporary civil speed limits.
It is also an object of this invention to provide an electronic interlocking system that includes a plurality of intelligent track circuits, wherein an intelligent track circuit provides additional statuses for the associated detection block, including the “always reporting block” status, and the “never reporting block status.”
The foregoing and other objects of the invention are achieved in accordance with a preferred embodiment of the invention by providing an electronic interlocking system, wherein the control logic of the interlocking is distributed between intelligent signal units that are interconnected by a wayside data network. The intelligent signal units are also connected to a programmable logic controller (PLC), which provides the non-vital selection functions, the associated Zone Controller (ZC) if Communication Based Train Control (CBTC) technology is used, and the Automatic Train Supervision (ATS) server if applicable. A signal unit includes one or more signal peripherals, and is controlled by an intelligent signal device (ISD) that includes a vital processor module, a data communication module, and an interface module. Each signal unit receives imported data, via the data communication module, from other signal units, the relevant PLC, ZC, and/or ATS server. Also, each signal unit exports data to other signal units, the relevant PLC, ZC, and/or ATS server to provide the status of the associated signal peripherals. Further, each signal unit receives input data related to the status of associated signal equipment via the interface module. Output data is generated by the vital processor module, and is used to activate the associated signal peripherals.
The configuration of a signal unit is a design choice that is subject to predefined rules. However, there is a plurality of generic signal units that are provided to simplify signal control logic design requirement, and to provide data driven, or parameter driven installations. Further, the unit configuration rules are designed to optimize the performance of the interlocking. In particular, the allocation of signal peripherals to the various signal units is driven in part by the objective to minimize the response time for the various interlocking functions. For example, an “Automatic Signal Unit” includes the automatic signal, its associated stop mechanism and circuit controller, and the track circuit for the detection block immediately ahead of the signal. The inclusion of said track circuit in the automatic signal unit ensures that the red aspect of the signal is activated almost immediately after a train crosses the insulated joint into the block ahead of the signal, and since the track circuit associated with said block is included in the automatic signal unit. Similarly, a “Switch Signal Unit” includes the track circuit associated with the first detection block in the reverse direction of traffic for the switch detector circuit to ensure that the switch is locked by its detector circuit as soon as a train crosses the corresponding insulated joint.
In addition, to reduce data communications between the various signal units, and in order to optimize the response time, the control logic for certain internal signal functions is repeated at a plurality of signal units, rather than communicating the status of said internal signal functions between signal units. For example, the control logic for route locking functions is repeated at opposing “Home Signal Units,” and could also be repeated at “Switch Signal Units.” In addition to reducing data exchanges between signal units, this concept of repeating internal signal functions in a plurality of signal units has the added benefit of minimizing the impact of a signal unit failure.
The concept of intelligent signal devices provides the inherent characteristic of isolating the control logic for all the functions associated with a signal device from the control logic of other signal devices. The only link between the control logic for two signal units is the communication link between the respective data communication modules. Because data flow between the two processors associated with two signal units is predetermined, it is a simple task to identify the signal units affected by a modification of the interlocking, or a change in the control logic for a signal unit. Such deterministic data flow between signal units makes it possible to provide a “Vital Change Management Process” (VCMP) to simplify the testing requirements associated with the disarrangement of an interlocking.
The VCMP could be implemented in a real time vital processor, which monitors changes to the interlocking configuration, data flow, and/or control logic, identifies testing requirements for affected signal units, and maintains records of successfully completed tests for signal units affected by a particular version or release. Upon the initiation of a new modification, and/or release, the VCMP first identifies existing and/or new signal units included in the modification and/or release then it determines additional signal units impacted by the modification and/or release using data flow information.
The Concept of intelligent signal units, also, presents an opportunity to provide enhanced safety, and operational flexibility for various signal equipment. For example, it would be possible to enhance the safety of an automatic signal by enabling and disabling the “Key-By” function from a centralized location (ATS for example). Additional safety function such as temporary civil speed limits, and protection for work zones could be implemented in a fixed block installation by employing the grade time control feature of signal units together with centralized control functions. Similarly, the states of a track circuit associated with a detection block could be expanded to include “Always Reporting Block” (ARB), and “Never Reporting Block” (NRB). Such expanded track circuit states could be used to enhance the safety and operational flexibility of train operation. For example, a new switch locking function could be activated if an associated detector block indicates an NRB status. Alternatively, an emergency screw release function for a switch could be enabled if an associated detector block indicates an ARB status. Obviously, the proper operating procedures must be followed for such emergency screw release operation.
Another safety enhancement is related to low adhesion conditions. The computing resources of an intelligent signal device are used to dynamically reconfigure the signal layout in an area upon the detection of a low adhesion condition. In effect, this new dynamic reconfiguration function will increase safe train separation, and is activated by a command from a centralized control location.
Further, because the control logic for an intelligent signal device is primarily dedicated to a specific signal apparatus, the control logic could be parameterized to provide a generic device dedicated to said specific signal apparatus. In this case the generic device is customized to a particular location by manipulating a set of parameters. Such generic device will also reduce the design and engineering tasks required for new signal installations, and will greatly reduce the number of circuit and detail drawings. For example, the control logic for an automatic signal unit could be configured as a generic control logic that is customized to a site specific location using a data base, and/or a plurality of parameters. The control logic will include all possible functions and features related to the home and distant controls for the automatic signal location, the automatic stop control, signal lighting requirements, and indication requirements. Internal vital parameters are then added to provide a means for selecting the specific functions and features associated with a particular location.
Also, one of the advantages provided by an intelligent signal device is to reduce the impact of signal failures on train operation, and to simplify the staging and tie-in process during the initial construction phase, and/or during the implementation of modifications to signal installations. This advantage is achieved in the above described automatic signal unit example by providing two sets of home and distant control logic, together with an enabling parameter that dynamically activates the appropriate set under pre-defined conditions. The first set of home and distant control logic is based on the location and other parameters of the signal ahead in the current signal arrangement layout. The second set is based on the location and other parameters of a different signal ahead in a modified signal arrangement layout. Said second set could then be activated to implement a tie-in task during a signal bulletin. This feature provides a measurable reduction in time and effort required to implement changes to signal installations.
Similarly, the second set of home and distant control logic could be based on the location and other data for the second signal ahead in the current signal arrangement layout. In such a case, this second set could be activated by a parameter to provide fast recovery from a failure at the first signal ahead. In effect, upon such failure, the first signal ahead is removed from service until it is repaired. Train service continues at normal operating speed with a longer home and distant controls. Obviously, if the nature of the failure is related to a track circuit failure, then this feature cannot provide recovery at normal operating speed. Also, the proper operating procedures should be implemented (proper aspect displayed, stop hooked or driven down, etc) when a signal is taken out of service.
The intelligent signal devices are interconnected by a wayside data network (WDN) that manages the data exchanges between the various signal devices, the associated PLC that provides the non-vital selection functions, the zone controller (if CBTC is used), and the ATS server if applicable. The WDN is designed to provide a resilient and fault tolerant backbone allowing high speed data exchange between the various signal devices that form the electronic interlocking. The network employs a fiber optic backbone with appropriate equipment to provide layer 2 communication services between the various elements of the interlocking, as well as layer 3 communication service (routing) to interface the elements of the electronic interlocking with the ATS server, and/or with operator consoles at dispatcher locations. All data messages exchanged between the various intelligent signal devices are time stamped, and are processed by vital processor modules to ensure freshness of data received. In the event of communication interruption, or a determination that the data received is not fresh, then default values are assigned to affected import data. Such default values are based on the safe state for each affected input variable. For example, the import data for the status of a track circuit will default to “occupied” upon loss of communication, or a determination that the received status does not comply with the freshness threshold. Alternatively, the import data for the status of a track circuit that is used to activate a timing function (such as grade time or station time) will default to “vacant” upon loss of communication, or a determination that the received status does not comply with the freshness threshold. This means that an import variable could have two different default values if it is used in two different applications.
It should be noted that the implementation of intelligent signal devices will simplify interface requirements with a CBTC system. Each intelligent signal device could communicate directly with the zone controller to provide the status of its associated signal equipment, and to receive override control data and other information generated by the CBTC zone controller. Alternatively, and as the state of the art for CBTC technology evolves, intelligent signal devices could communicate directly with vital computers on board approaching trains to provide status information, and receive override data. Also, intelligent signal devices could be interconnected with dynamic transponders in non-CBTC territory to provide the status of wayside signals to the transponders. In turn, said dynamic transponders could transmit a plurality of variable civil speeds to approaching CBTC trains based on the aspects of wayside signals. Furthermore, an intelligent signal device could be interfaced with vital wheel detectors to provide speed measurement or axle counter functions.
It should also be noted that the concept of intelligent signal devices could be partly employed in a signal installation. The extent this concept is implemented at an interlocking is a design choice. For example, intelligent signal devices could be employed to control the automatic signals between two interlockings, while maintaining conventional relay or solid state interlocking (with centralized intelligence) to control the signal equipment at the interlockings (home signals, approach signals, switch machines, etc). Alternatively, automatic, approach, and home signals could be implemented using intelligent devices, while maintaining centralized logic for switches, traffic signals, and other signal equipment.
Further, intelligent signal devices could be provided in a centralized location for the purpose of isolating the control logic for the various signal equipment from each other. In such a case, the main objective for employing intelligent signal devices is to minimize the probability of a catastrophic failure that would impact the entire interlocking, and to employ the deterministic data flow characteristic of distributed intelligence for the purpose of providing a Vital Change Management Processor. Obviously, in such a case, and since the intelligent signal devices are co-located in a single location, line cables are required to interconnect field equipment with the various interface modules.
Another design alternative is to implement the intelligent signal devices as individual state machines that operate on fault tolerant, and vital hardware architecture. In such a case, each state machine represents an intelligent signal device, and is logically isolated from other state machines operating on said fault tolerant hardware. Such logical isolation is implemented in a vital manner to ensure the integrity of the Vital Change Management Process. In such a case each type of state machine could be parameterized to minimize design efforts, and data is exchanged between the various state machines in a manner that is similar to the data flow between individual intelligent signal devices that are interconnected by a wayside data network.
These and other more detailed and specific objectives will be disclosed in the course of the following description taken in conjunction with the accompanying drawings wherein:
The preferred embodiment of the present invention provides a structure, or a process to control interlocking devices, and to control the safe operation of trains over sections of signaled track territory. For a typical interlocking installation that includes at least one track switch, a plurality of wayside signals and associated stop mechanisms (for transit application), and a plurality of detection blocks, the current invention configures the interlocking elements into a plurality of signal units, each of which has an independent vital control device. These vital control devices are interconnected by a data network that manages the data exchanges between the devices. Unlike a conventional interlocking that employs centralized control logic, the current invention segregates the interlocking control logic by type of interlocking element.
For example, in a typical interlocking configuration the control logic for track switch machines, home signals, approach signals, automatic signals, and directional traffic signals are segregated from each other. Such segregation, combined with placing vital control devices at close proximity to the physical trackside signal devices, provide many benefits. These benefits include minimizing the operational impact of a failure, minimizing line cable requirements, making it possible to develop a generic, parameter driven control device for each type of signal element, simplifying design, testing and commissioning tasks for the initial installation, as well as after a disarrangement of the interlocking, and simplifying the interfaces between trackside signal devices, and other signal devices such as Programmable Logic Controllers (PLC), Zone Controllers, and ATS servers.
In order to minimize data exchanges between signal unit devices, certain signal control logic could be duplicated within different signal units rather than transmitting additional data between units. For example, route locking functions could be duplicated within the devices that control home signals, and the devices that control track switches. The logic could also be repeated within the PLC that provides the non-vital selection functions for the interlocking. In addition to reducing data exchange requirements, this design approach will minimize the failure impact of one unit on the remaining control devices at an interlocking.
Referring now to the drawings where the illustrations are for the purpose of describing the preferred embodiment of the invention and are not intended to limit the invention hereto,
The entire interlocking is then configured into signal units of the types described above. Each signal unit is controlled by an intelligent signal device (ISD), which includes a communication module 32, a vital processor module 34, and an interface module 36 as shown in
The interface module 36 includes a set of vital I/O boards each of which is designed to interface with a specific type of signal equipment. Typical vital I/O boards known in the art include a signal lighting board, a stop machine board, a switch machine board and a track circuit board. A general purpose vital I/O board is used to provide “dry contact” interface to electromechanical equipment such as relays, contactors, etc. Further, each type of vital I/O board could include a plurality of boards to interface with different versions of trackside equipment 38. For example, a signal lighting board could include low voltage DC board to interface with LED aspects, as well as low voltage AC and high voltage AC boards to interface with incandescent lamp aspects. Similarly, a stop machine board could include a high voltage AC board to drive the stop motor for an all-electric stop machine, and a low voltage DC board to activate the stop valve for an electro-pneumatic stop machine.
As would be appreciated by a person skilled in the art, a vital I/O board could include certain intelligence of its own. For example, it is preferable that the signal lighting board includes intelligence that provides a “Light Out” detection function. Upon the detection of a light out condition in an aspect, the intelligent I/O board provides a signal to the associated ISD, which in turn modifies the indications displayed at other aspects within the associated signal, and activates the appropriate alarm functions. Similarly, a high voltage AC stop machine board could include intelligence that senses a high in-rush current. Further, it desirable that each I/O board is designed to detect any ground conditions on the local copper wiring that interconnects trackside signal equipment with the ISD. Upon the detection of a ground condition, the I/O board is turned off.
In general, the interface module 36 shown in
As indicated in
The generic operation of an ISD consists mainly of receiving data related to the states of other signal units, determining and/or controlling the operational states of associated signal equipment, and communicating said operational states to other signal units. To accomplish these tasks, and ensure efficient data flow between the various ISD's, the vital processor module 34 of an ISD employs two sets of data. The first set is related to the data exchanged with other intelligent signal devices, and is configured as import data, and export data. Further, the import data includes two data fields for each data element. The first field identifies the data element, and the second field identifies its origin (i.e. the ISD location where the data element originated). Similarly, the export data includes a field that identifies a data elements that is generated at the ISD location, and a second field that identifies the destination address(es) for said data element. The second set is related to data exchanged with trackside equipment associated with the ISD location, and is configured as input data and output data. The input data represents the statuses of trackside equipment, such as track circuits, switch machines, stop machines, etc. The input data also includes any data generated by intelligent I/O boards, such as light out conditions for signal aspects. The output data represents the control signals generated by the vital processor module 34, such as signal aspects, stop control signal, switch activation signal, etc.
An example of import/export data configuration for 353 automatic signal unit is indicated in
The above example demonstrates one of the advantages of the ISD concept presented herein related to the simplification of changes, and tie-in tasks. To modify a traditional hard-wired system would normally require the addition of cables/equipment and/or wiring changes. Similarly, to interface a hard wired signal installation with CBTC would normally require the addition of cables, interface racks, as well as wiring changes in the existing equipment. Under the ISD concept, tie-in tasks and/or interfaces with CBTC would require modification to the internal logic of affected ISD's, and changes to the data configuration, thus eliminating the need for additional wiring and equipment and/or wiring changes. Further, if the ISD internal logic is parameterized, then tie-in tasks and/or interfaces with CBTC would require only modification to the data and/or parameter configuration.
The input/output data configuration for an ISD is structured similar to the import/export data configuration as indicated in
One of the main characteristics of the ISD concept is that the control logic that resides within an ISD is dedicated to a specific type of signal element, and is segregated from the control logic of other types of signal equipment. For example, the control logic 64 for 353 automatic signal unit, shown in
A generic ISD incorporates the logic for all possible functions, and site specific features for a type of signal equipment. The ISD also incorporates a plurality of internal vital parameters that are integrated with said logic to provide a means for selecting the desired functions and features at a particular location. There are two types of parameters used in this ISD concept. The first type is related to a parameter that activates a function or a feature. The second type is related to a parameter that enables a function or a feature. Both types of parameters are set by a signal engineer at the time an ISD is programmed, or is customized to a particular location. An activating parameter is set to either “TRUE,” i.e. “ACTIVATED,” or “FALSE,” i.e. “NOT ACTIVATED.” Similarly, an enabling parameter is set to either “TRUE,” i.e. “ENABLED,” or “FALSE,” i.e. “NOT ENABLED.” A function or a feature that is enabled can be activated and de-activated by a user input, typically from an operating console. In effect, a parameter is used to either select or bypass a logic module in a parameterized logic configuration.
To customize an ISD to a particular location, a programming tool with a display device is used. A graphic user interface (GUI) is provided to enable a designer, or a signal engineer to select & activate parameters, and enter the required site specific data. The signal engineer is presented with a series of screens that include the various parameters related to the type of signal equipment controlled by the ISD. The design of the programming kit is such that upon the selection of general or high level parameters, additional screens are presented to the signal engineer to further customize the ISD to the specific site or location. There are two sets of graphic user interface screens. The first set is related to the signal control logic for the ISD, and enables the signal engineer to define the functional requirements of the location, and identify the required site specific data. The second set of screens is related to the communication logic for the ISD, and enables the signal engineer to define the import and export data, as well as the origination and destination addresses. In addition, and as would be appreciated by a person skilled in the art, the design for the programming kit could incorporate safety checks, plausibility determinations, and cross checks to detect the selection of contradictory parameters, or obvious errors in the parameterization configuration of the device.
To demonstrate the concept of generic intelligent signal devices, an example of a generic ISD for an automatic signal unit is disclosed for the preferred embodiment.
An example of the parameterized diagram for the “Home Control” functions is shown in
These parameters are also integrated in the logic modules for the secondary logic functions. For example, in
To set the activating & enabling parameters for the “Home Control” functions, the signal engineer is presented with a series of graphic user interface screens that indicate all of the available parameters. First, the signal engineer is instructed to activate the desired secondary control functions for the “Home Control” as shown in
Similar to the “Home Control” function, an example of the parameterized diagram for the “Distant Control” function is shown in
An example of the parameterized diagram for the “Signal Lighting” function is shown in
An example of the parameterized diagram for the “Stop Control” functions is shown in
An example of the parameterized diagram for the “Block Detection” functions is shown in
An example of the parameterized diagram for the “Indication” functions 81 is shown in
In addition to the above described six (6) primary signal control functions, there are a number of main parameters that define the signal equipment present at an automatic signal location. Examples of these parameters are shown in
The design of the programming kit is such that it detects obvious errors, and inconsistent selections by the signal engineer. For example, with respect to the main parameters shown in
It should be noted that different and/or additional detailed parameter screens are presented to the signal engineer based on which parameters were activated in previous screens. For example, the detailed parameter screen for the “STATION TIME CONTROL” function shown in
The second set of graphic user interface screens is related to the configuration of import and export data. Similar to parameterized logic, a parameterized data configuration simplifies the effort required to identify the import data, and their origins, as well as the export data, and their destination addresses. Because most of the data exchanged takes place between the ASU 20 indicated in
Similarly,
As would be understood by those skilled in the art, different or alternate parameterized diagrams could be used. Further, different logic diagrams than those indicated in
The WDN 40 is designed to provide a resilient and fault tolerant backbone that enables high speed data exchange between the various intelligent signal devices that form an electronic interlocking. It is preferable that the network employs a fiber optic backbone with appropriate equipment to provide layer 2 communication services between the various elements of the interlocking, as well as layer 3 communication service (routing) to interface the elements of the electronic interlocking with the ATS server, and/or with operator consoles at dispatcher locations.
All data messages exchanged between the various intelligent signal devices are time stamped, and are processed by vital processor modules to ensure freshness of data received. In the event of communication interruption, or a determination that the data received is not fresh, then default values are assigned to affected import data. Such default values are based on the safe state for each affected input variable. For example, the import data for the status of a track circuit 162 will default to “occupied” (“FALSE”) upon loss of communication, or a determination that the received status does not comply with the freshness threshold as shown in
It should be noted that, and as would be appreciated by one skilled in the art, the wayside data network could be implemented by wireless means using Real Time Communication (RTC) protocols. In such case, each ISD is equipped with a data network that effectively establishes communication through appropriate network architecture to enable the exchange of data between the various ISD's. Such wireless approach has the added advantage of enabling direct communication between CBTC equipped trains, and Intelligent Signal Devices.
The allocation of dedicated vital computing resources to specific types of signal equipment, and the concept of intelligent signal devices, makes it feasible to enhance the safety, and operational flexibility of signal installations. The automatic signal unit described in the preferred embodiment provides a number of safety enhancements to train detection, and automatic signal operation. For example, using the computing resources that are dedicated to an automatic signal unit, it is feasible to provide an intelligent track repeater function as shown in
Similarly, it would be possible under certain conditions to detect a “Never Reporting Block” (NRB) by comparing sequences of dropping, and activating a plurality of adjacent track circuits. The example shown in
Other safety and operational enhancements provided by the ISD that control the ASU described above include the temporary speed restriction shown in
Further, the ISD concept would enable the implementation of dynamic home and distant control functions as illustrated in
To implement these dynamic functions, a remote I/O device 192 that is associated with the ISD device 190 at the ASU location is used to exchange data between the ASU location and the “Next” signal location as shown in
The dynamic reconfiguration described herein provides a mean to quickly recover from certain types of failure, and enables train service to continue at normal speed, but with longer headway in the affected area. Another application to this dynamic reconfiguration is to extend both the home and distant controls for all signals in an area upon the detection of low adhesion condition. In such a case, upon the activation of a central control command, dedicated logic at each ASU location will first check that the new home control limit for the signal is clear before implementing the extended home control. This will ensure that the signal is not flashed to a stop aspect when this function is implemented.
It should be noted that the concept of employing a remote I/O device 192 to exchange data between one ASU location and the “Next” signal location (
It should also be noted that the concept of segregating the vital control logic for a specific type of signal element from the vital control logic of other types of signal elements could be implemented without the use of individual intelligent signal devices. For example, the vital control logic for an interlocking could be configured as a plurality of segments or processes, wherein each segment or process provides the entire logic for a particular signal unit. Also, a separate logic segment would be required for each signal unit location. Further, although said plurality of segments or processes could run on the same hardware resources, they must be logically, and vitally isolated from each other. The only link between these segments is a communication structure that provides a means to exchange data between the segments. Similar to the hardware implementation of intelligent signal devices, each segment or process includes import and export data configurations, as well as input and output data configuration for associated trackside devices. A separate I/O interface module could be provided for each segment or process, and such module could be remotely located in the vicinity of the associated trackside equipment. Furthermore, the process or software segment for each type of signal equipment could be parameterized in order to minimize design and engineering tasks.
Obviously, this configuration of separate software segments on centralized hardware resources will not provide all the benefits provided by intelligent signal devices, however, such configuration has the advantage of providing a structured approach for testing or retesting of a signal installation after the disarrangement of an interlocking. In both the ISD implementation, and the in a centralized configuration that employs isolated software segments, a Vital Change Management Process (VCPM) could be used to determine testing requirements after a modification is made to an existing signal installation.
As would be understood by those skilled in the art, alternate embodiments could be provided to implement the new concepts described herein. For example, different diagrams could be derived for the control logic associated with an automatic signal unit. Also, different parameters could be used to provide a generic automatic signal unit. Furthermore, many programs may be utilized to implement the logic presented in the various figures herein. Obviously these programs will vary from one another in some degree. However, it is well within the skill of the signal engineer to provide particular programs for implementing each logic for the functions disclosed herein. Further, the concept of using a plurality of parameters to develop a generic signal device could be used with any signal device such as an approach signal, a home signal, a switch, etc. It is also to be understood that the foregoing detailed description has been given for clearness of understanding only, and is intended to be exemplary of the invention while not limiting the invention to the exact embodiments shown. Obviously certain subsets, modifications, simplifications, variations and improvements will occur to those skilled in the art upon reading the foregoing. It is, therefore, to be understood that all such modifications, simplifications, variations and improvements have been deleted herein for the sake of conciseness and readability, but are properly within the scope and spirit of the following claims.
This is a continuation application of patent application U.S. Ser. No. 14/149,972, filed in the Patent and Trademark Office on Jan. 8, 2014, which is a continuation of U.S. Ser. No. 13/506,358, filed in the Patent and Trademark Office on Apr. 13, 2012, and which was issued as U.S. Pat. No. 8,695,972, which is a continuation of U.S. Ser. No. 12/313,757, filed in the Patent and Trademark Office on Nov. 24, 2008, and which was issued as U.S. Pat. No. 8,214,092, which benefits from provisional application U.S. Ser. No. 61/004,824 filed in the Patent and Trademark Office on Nov. 30, 2007.
| Number | Date | Country | |
|---|---|---|---|
| 61004824 | Nov 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 14149972 | Jan 2014 | US |
| Child | 15646875 | US | |
| Parent | 13506358 | Apr 2012 | US |
| Child | 14149972 | US | |
| Parent | 12313757 | Nov 2008 | US |
| Child | 13506358 | US |
