Railcar Order Identification via Brake Pipe and Wireless Timing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the sequence of railcars connected to a locomotive on a train face challenges such as multiple trains responding to brake test signals from the wrong locomotive, especially when trains are positioned close together, and require electrical connections that may not be feasible for all railcars.

Innovation Solution

A method utilizing a brake pipe as a slow network for transmitting a unique identification code and measuring time delays via a fast wireless network to determine the distance of railcars from the locomotive, ensuring only connected railcars respond to the correct locomotive, even when some are not equipped with control devices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If brake test signals are transmitted to determine car order, then railcars can be identified, but multiple trains standing close together cause false responses from railcars not connected to the transmitting locomotive

Engineering Contradiction:
Improvecar order identification accuracyVSAvoidfalse response rate
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The system performs preliminary actions by first establishing a unique identification code through the brake pipe communication before attempting to determine car order. This preliminary code exchange ensures that only railcars connected to the specific locomotive will respond to subsequent identification commands, preventing false responses from trains standing close together.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The brake pipe serves as an intermediary communication channel that carries both the unique identification code and the car order determination signals. This intermediary mechanism ensures that communication is restricted to connected railcars only, as the identification code must be received through the brake pipe before the railcar will respond to identification requests.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If electrical communication connections are used between railcars, then reliable data exchange is achieved, but the system becomes infeasible when some railcars lack control devices

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidcompatibility with mixed equipment levels
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The system uses pneumatic communication through the brake pipe to transmit the unique identification code to railcars. This pneumatic approach replaces the requirement for electrical communication connections, allowing reliable identification even when some railcars lack control devices or electrical communication capabilities. The brake pipe communication is universally applicable across all railcars in the train.

Inventive Principle:
Principle #29Pneumatics and hydraulics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Ensures accurate identification of connected railcars by using pressure variations in the brake pipe for encoding identification codes, allowing distance calculation and response only from relevant railcars, even in close proximity or with varying equipment levels.

Implementation Method 1

Transmitting, by the control device of the locomotive of a unique identification code to the railcar control devices via a slow network constituted by the brake pipe

Methodology Applied
Scientific EffectPressure variations: Pressure Gradient

Implementation Method 2

the locomotive control device of the locomotive and the control devices of the railcars may exchange messages via a fast network

Methodology Applied
Scientific EffectWireless communication: Electromagnetic Induction

Implementation Method 3

Determining, by the railcar control devices, of a time delay between the state of the transmission received from the locomotive control device and a state of the transmission measured on the slow network

Methodology Applied
Scientific EffectTime delay measurement: Time of Flight

Data Source

PatentEP4011746B1Method for identification of a car order on a train and control device for a railcar
Publication Date: 2026.01.28 KNORR BREMSE SYST FUR SCHIENENFAHRZEUGE GMBH
  • EP4011746B1 patent drawingFigure 1~2

AI summary

A method for determining a sequence of railcars (14, 16, 18, 20) connected to a locomotive (12) on a train (10), wherein a control device (28) of the locomotive (12) is connected to railcars (14, 16, 20) comprising a control device (30, 32, 34) via a brake pipe (22), wherein the control device (28) of the locomotive (12) and the control devices (30, 32, 34) of the railcars (18, 16, 20) may exchange messages via a fast wireless network (52), comprises the following steps: Transmitting, by the control device (28) of the locomotive (12) of a unique identification code to the control devices (30, 32, 34) via a slow network constituted by the brake pipe (22); Transmitting, by the control device (28) of the locomotive (12) over the fast network, of messages indicative of a current state of the transmission carried out via the slow network, wherein the messages comprise the unique identification code; Determining, by the control devices (30, 32, 34), of a time delay between the state of the transmission received from the control device (28) and a state of the transmission measured on the slow network; Calculating a distance of each railcar (14, 16, 20) to the locomotive (12) from the time delay and a propagation velocity of the slow network; Requesting, by the control device (28) of the locomotive (12) of a report relating to the calculated distance and/or measured time delay by each railcar (14, 16, 20); Sending, by the control device (30, 32, 34), a report in response to the above request, if an identification code in the request matches an identification code received via the slow network and Ordering the railcars (14, 16, 20) by their distance to the locomotive (12). A Control device (30, 32, 34) for a railcar (14, 16, 20), wherein the control device (30, 32, 34) comprises a pressure sensor (38, 40, 42) for detecting pressure changes within a brake pipe (22) connected to a locomotive (12), wherein the control device (30, 32, 34) is configured to decode an identification code of the locomotive (12) encoded in the pressure changes, wherein the control device (30, 32, 34) further comprises a communication unit (46, 48, 50) for communicating over a wireless communications network (52) and wherein the control device (30, 32, 34) is configured to only respond to requests from a locomotive (12) if an identification code sent with such a request corresponds to the identification code decoded from the pressure changes.