Vehicle-to-Platform Distance Measurement Using Filtered Multi-Ray Sensing

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Solution Overview

Problem

Existing methods fail to provide a reliable measurement of the distance between a railway or road transport vehicle, particularly guided vehicles, and a platform, which is crucial for accurately adjusting the vehicle's height to minimize the vertical gap and facilitate passenger boarding and disembarking.

Innovation Solution

A method involving a detection system on the vehicle that projects laser or radar beams to measure distances, filters out aberrant data, and calculates the vertical and horizontal distances to the platform edge, allowing precise adjustment of the vehicle's height and gap filler dimensions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing distance measurement methods are used, then the measurement process is simple, but the measurement reliability is insufficient

Engineering Contradiction:
Improvedistance measurement reliabilityVSAvoiddetection system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The detection system divides the measurement task into multiple independent components: a laser projector that emits multiple rays at different angles, a detection system that captures reflections from these rays, and a processing unit that separates valid platform measurements from invalid reflections. This segmentation allows each component to perform a specific function efficiently, improving overall reliability without requiring a single complex system.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary processing stage that acts as a filter between raw detection data and final measurements. This intermediary unit analyzes the reflected rays, identifies which ones correspond to the platform surface versus other obstacles, and selects only the valid measurements for distance calculation. This intermediary step ensures measurement reliability by eliminating erroneous data before final processing.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If multiple rays are projected to improve measurement accuracy, then the vertical distance measurement becomes more precise, but the data processing complexity increases

Engineering Contradiction:
Improvevertical distance measurement precisionVSAvoiddata processing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The processing system segments the multiple detected rays into distinct categories: rays that reflect off the platform surface (valid measurements) and rays that reflect off other objects or the ground (invalid measurements). By processing rays in this segmented manner rather than treating them as a single complex dataset, the system achieves high measurement precision while keeping data processing manageable through systematic classification.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The processing unit extracts only the relevant information from the multiple detected rays - specifically identifying and selecting only those rays that correspond to reflections from the platform surface. This extraction process filters out unnecessary or erroneous data, leaving a clean set of measurements that can be processed to calculate vertical distance with high precision without the complexity of processing all detected reflections equally.

Inventive Principle:
Principle #2Taking out (Extraction)

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

Enables reliable measurement of distances for precise vehicle height adjustment and gap filler adaptation, enhancing passenger access by minimizing the vertical gap between the vehicle and platform.

Implementation Method 1

projection by the detection system of a plurality of rays, for example laser rays

Methodology Applied
Scientific EffectLaser: Laser

Implementation Method 2

detecting the ray reflected by an obstacle and of measuring the time interval between the emitted ray and said reflected ray

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 3

measuring the time interval between the emitted ray and said reflected ray, so as to calculate the distance between the detection system and the obstacle

Methodology Applied
Scientific EffectTime of Flight: Time of Flight

Data Source

PatentEP3995855B1Method for measuring a distance from a vehicle to a dock
Publication Date: 2026.04.15 ALSTOM HOLDINGS SA
  • EP3995855B1 patent drawingFigure 1
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AI summary

The invention relates to a method for measuring a given distance between a vehicle (10) and an upper surface (14) of a platform (16), comprising the following steps: - projection of a plurality of rays (20) by a detection system (18) mounted on the vehicle (10), the rays being contained in the same projection plane in the direction of the platform (16), - measurement, for each ray (20), of a distance (Dn) between the detection system (18) and the platform (16) along a respective direction of said ray (20) - exclusion of a first part of the measured distances (Dn) comprising the measured distances not corresponding to the upper surface (14), and - calculation of a vertical distance between a reference point of the vehicle (10) and the upper surface (14) of the platform (16) from distances not included in the first part.