New Rail TechnologySignal and Train Control SystemsBill Petitwww.billpetit.comRailway Age ConferenceDecember 12, 2008

What Ill Talk AboutHow we got where we areIssues affecting application of new technologyOverview of new technology applicationsParticularly PTC Whatever that means

How We got here History of Train Control Part 1

Track Warrant Control(Dark Territory)Movement Authority conveyed by track warrant Permission to occupy a Block of trackVerbal communication

Automatic Block Signal (ABS)Two main tracks, each with an assigned direction of movementMovement authority and operating speed conveyed by signal systemTracks are signaled only for movement in assigned directionTrain separation and operating speed information provided by signal system

Train Control System (TCS)(or cTc)Multiple main tracks, each signaled for traffic in both directionsMovement authority and operating speed conveyed by signal systemTrain dispatcher controls switches and signals from distant location

TCS with Cab Signals and Speed Control

Multiple Main Tracks, each signaled for traffic in both directionsMovement authority and operating speed conveyed by signal system with information sent through the railsTrain dispatcher controls switches and signals from distant locationTrain separation and speed limit provided by train crew and onboard equipment

Issues Affecting new technology applicationsCostReliabilityEnvironmentalSafetyLow probability, high consequence1000s of units in the field30 + year lifetime

What Do I Mean by SafetySystem Designed to correctly perform all operational requirements under normal conditionsSystem Designed to correctly perform all operational requirements under adverse conditions (environmental, system stress)

What Do I Mean by SafetySystem does not provide more permissive outputs under failure conditionsSystem or subsystemAll single point self-revealing failuresLatent (secondary) failures for non-self-revealing failures

Particular Issues with processor-based systemsFailures are non-linearSingle transistor failure within IC leads to an unknowable result. (weak-link behavior)Complexity

Over-reliance on redundancy

New Technology Systems

Enabling TechnologiesPosition Locating SystemsVehicle determines its own position, instead of relying on operator reporting or track circuitsTranspondersSatellite Locating Systems (e.g GPS)

Enabling TechnologiesMobile Data CommunicationsAbility to transmit increased amounts of dataAbility to track mobile node through the systemCan be used to convey information to the engineer in ways other than verbal (written) orders, wayside signals or cab signals

Enabling TechnologiesIncreased Processing PowerAbility to support other enabling technologies

Technology Examples

Electronic Train Management System (ETMS)Implemented on BNSF on pilot projectsSafety plan approved by FRA for use as an overlay systemExisting system must be maintained and used for safetyBased on Forms-Based (train order) architecture)

Track Warrant Control(Dark Territory)Train Orders conveyed verbally and repeated for confirmation (i.e. no change)Plan to send digital version of text for onboard display but not approved yet.Train orders encoded digitally at office and sent to locomotive (unseen by engineer) and enforced by onboard system based on GPS location.Also capable of reading status of existing wayside signals and enforcing them.

Electronic Train Management System (ETMS)Class I railroads are moving ahead with this architectureCSX CBTMUP V-TMSNS - OTC

Advanced Civil Speed Enforcement System (ACSES)In-Service on Amtrak NorthEast CorridorBased on Cab Signal Architecture.Utilizes existing cab signal Adds onboard database of civil and infrastructure dataTransponders used for position location.

Advanced Civil Speed Enforcement System (ACSES)Train separation and operating speed obtained from existing cab signal infrastructureCivil speeds enforced from onboard databasePositive stop enforced with data from onboard databasei.e. length of block, grade, curve, etc.

Advanced Civil Speed Enforcement System (ACSES)Temporary Speed Restrictions conveyed by radio from office and enforced based on onboard database.

ACSES - The Equipmentplus radio set(s) cables, serial links, brackets, connections to train brakes...Train borne

Incremental Train Control System (ITCS)In revenue service on Michigan HSR corridor and in ChinaUses cab signal based architectureMichigan uses existing wayside infrastructureChina uses virtual blocks and signals

Interoperable Communication-Based Signaling (ICBS)Industry effort to provide standards for interoperability based on a signaling-based architectureSupported by Alstom, GETS, Safetran and US&SInitial set of standards approved and published in current version of AREMA Manual of Recommended Practices for Communication and Signaling

ICBS ProjectDemonstration project in process funded by FRASupported by Alstom, GETS, Safetran and US&S

What we set out to doDefine Interoperability for a PTC system based on signaling principlesComplete system providing stand-alone ability to set and protect routes, deliver onboard authorities in terms of aspects, enforce onboard authorities including civil speed and pre-emptive braking (positive stop)Focus on train controlWork with interoperable comms system per RESCBasic system defined with ability to add additional functionality as needed.

What we didAgreed to and published architecture and interoperability recommended practices through a Professional Industry Association (AREMA)Through FRA and Private (supplier) fundingDefined Test Layout to incorporate multiple suppliersDeveloped Communications Router and Simulators for Test EnvironmentSubstituted 2 sets of suppliers equipment for one of the simulators3rd supplier to be integrated next week

Basic Territory for each supplier to simulate

GETSSafetranUS&SAlstomOverall Territory with Each Supplier covering One Section

Representation of Overall Test Layout

SLP (GETS VHLC)Interfaces to Genisys Control OfficeProcesses Signaling LogicInterfaces to SLP Protocol ConverterReceives Block StatusesTransmits Switch & Signal StatusesInterfaces to WA for Switch ControlGETS SLP Equipment RackDiagnostic TerminalSLP Protocol ConverterConverts Between GE and ICBS MessagingUses ICBS Database for Status MappingTransmits Block Statuses to GE SLPReceives Switch & Signal Statuses from GE SLPInterfaces to Comm. Router (ICBS Network)WA (GETS VHLC)Interfaces to SLPReceives Switch Control Statuses from SLPTransmits Switch Position Statuses to SLP

OBLP (GETS ITCS Onboard Computer)Location Determination Using ITCS Equivalent DatabaseEnforces TargetsInterfaces to OBLP Protocol ConverterTransmits Block StatusesReceives Switch & Signal StatusesInterfaces to Vehicle Simulator & Loco Interface PanelGETS OBLP Equipment RackVehicle Simulator & Diagnostic TerminalOBLP Protocol ConverterConverts Between GE and ICBS MessagingUses ICBS Database for Status MappingReceives Block Statuses from OBLPTransmits Switch & Signal Statuses to OBLPInterfaces to Comm. Router (ICBS Network)Locomotive Interface PanelAcknowledgement InputReverser Handle InputIn/Out Mode SwitchGETS ITCS Locomotive Display

Alstom ICBS SLP and WA Equipment RackPower SupplyVPI2 WAWA Local PanelVPI2 SLPVPI Power andVRD RelaysEthernet Hub

Questions ?Bill.Petit@ieee.orgwww.billpetit.com

Need to understand the history of signaling and train control so we can understand the system concepts as a way of determining where the system concepts should be updated with new technology, or when new technology should change basic system concepts.

Also need to understand some of the system constraints so we can determine how technology can address those constraints

With an understanding of these concepts and constraints, we can look to see what technologies can help improve safety and operations in the future.