Rail Vehicle Braking Control via Dynamic Force Redistribution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Rail vehicles experience under-braking or over-braking due to variations in adhesion, friction, and braking system faults, leading to inconsistent braking distances and potential safety hazards, particularly in local public transport where maintaining minimum distance between consecutive vehicles is critical.

Innovation Solution

A method involving a common brake control device that coordinates and adapts the activation of distributed braking devices to maintain precise deceleration by continuously comparing actual deceleration with a setpoint value, adjusting braking forces and effects in response to changing conditions, and redistributing braking forces across different carriages and types of braking systems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Force

If individual braking devices are actuated independently with higher braking pressure to compensate for reduced braking force, then braking force is increased, but the risk of over-braking increases when adhesion conditions improve

Engineering Contradiction:
Improvebraking forceVSAvoidbraking precision
Core Design Contradiction:
ForceVSReliability

Solution Approach 1:

The patent implements a common brake control device that continuously monitors the actual deceleration of the rail vehicle and compares it with the desired deceleration. Based on this feedback, the control device dynamically adjusts the activation of individual braking devices to maintain precise deceleration control. This prevents both under-braking and over-braking by responding to real-time adhesion conditions rather than relying on fixed brake pressure settings.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent merges the control of multiple distributed braking devices under a single common brake control device. Instead of independently controlling each braking device, the system coordinates all braking devices through centralized control that considers the overall deceleration requirements and adhesion conditions across the entire rail vehicle, enabling optimized force distribution.

Inventive Principle:
Principle #5Merging (Combining)

2Force

If braking pressure is increased to ensure sufficient braking force, then braking effectiveness is improved, but wheel locking and sliding occur leading to longer braking distances

Engineering Contradiction:
Improvebraking effectivenessVSAvoidwheel-rail friction control
Core Design Contradiction:
ForceVSEase of operation

Solution Approach 1:

The patent applies different braking forces to different wheel axles based on their local adhesion conditions. The common brake control device distributes braking force selectively to axles with sufficient adhesion while reducing or preventing braking on axles at risk of locking. This localized control of braking force prevents wheel sliding while maintaining overall braking effectiveness.

Inventive Principle:
Principle #3Local quality

3Reliability

If anti-skid devices reduce brake pressure to prevent wheel locking, then wheel sliding is prevented, but under-braking occurs when adhesion is insufficient

Engineering Contradiction:
Improvewheel locking preventionVSAvoidbraking force
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The system dynamically adjusts braking force distribution based on real-time adhesion conditions detected by anti-skid devices. When adhesion is insufficient, the common brake control device redirects braking force to other axles with better adhesion conditions rather than simply reducing overall brake pressure. This dynamic redistribution maintains braking force while preventing wheel locking.

Inventive Principle:
Principle #15Dynamics

4Force

If braking force is increased to compensate for adhesion loss, then braking force is maintained, but over-braking occurs when adhesion increases during braking

Engineering Contradiction:
Improvebraking forceVSAvoidbraking distance control
Core Design Contradiction:
ForceVSMeasurement precision

Solution Approach 1:

The common brake control device continuously monitors actual deceleration and compares it with the desired deceleration profile. When adhesion conditions improve during braking, the feedback mechanism detects the increased deceleration and automatically reduces braking force to maintain the target deceleration, preventing over-braking and ensuring precise stopping position.

Inventive Principle:
Principle #23Feedback

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

This approach ensures precise braking, minimizing the risk of under- or over-braking, maintaining safe distances between rail vehicles, and adapting to varying adhesion and environmental conditions, thereby enhancing safety and operational efficiency in rail transport.

Implementation Method 1

pneumatically controlled compressed air friction brakes such as block and disc brakes

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

the maximum static friction force that can be transferred from the wheel to the rail

Methodology Applied
Scientific EffectStatic friction: Static Friction

Data Source

PatentEP3113993B1Method for controlling a breaking system of a rail vehicle
Publication Date: 2021.10.20 KNORR BREMSE SYST FUR SCHIENENFAHRZEUGE GMBH
  • EP3113993B1 patent drawingFigure 1
  • EP3113993B1 patent drawingFigure 2

AI summary

The invention relates to a method for controlling a breaking system of a rail vehicle, said break system comprising several braking devices. The deceleration of the rail vehicle is controlled during braking, by means of a common brake control device which is connected to the brake devices, for a corresponding variable control of the brake devices to a desired target value.