Optical Speed Estimation for Track-Guided Vehicles Without Odometry

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the speed of track-guided vehicles suffer from high cumulative errors during extended periods of operation and are costly due to the complexity of using odometry and other positioning systems.

Innovation Solution

A method utilizing imaging sensors to capture and analyze a sequence of images, identifying characteristic image areas, and calculating speed based on the perspective shift of these areas, independent of wheel slippage, combined with a computing environment for processing and implementing this method.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If odometry-based positioning methods (balises, radar, GPS, odometers) are used to determine vehicle speed and position, then positioning accuracy is improved, but device complexity and cost increase

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical odometry systems (balises, radar, odometers) with an optical system using imaging sensors and image processing algorithms. The speed determination is achieved by analyzing perspective shifts of characteristic image areas in sequential images, eliminating the need for mechanical sensors and complex positioning infrastructure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Duration of action of moving object

If relative positioning is used to determine vehicle position from the last known location, then positioning can be maintained during extended operation, but cumulative measurement error increases with measurement duration

Engineering Contradiction:
Improveoperation durationVSAvoidpositioning accuracy
Core Design Contradiction:
Duration of action of moving objectVSMeasurement precision

Solution Approach 1:

The patent implements a feedback mechanism where the imaging sensor continuously captures images and the system periodically recalibrates by identifying characteristic image areas and calculating perspective shifts. This continuous optical feedback loop corrects cumulative errors by referencing fixed environmental features, maintaining positioning accuracy over extended operation periods.

Inventive Principle:
Principle #23Feedback

3Speed

If conventional odometry with displacement pulse generators and radar sensors is used to measure vehicle speed, then speed measurement is achieved, but the system becomes complex and costly

Engineering Contradiction:
Improvevehicle speed measurementVSAvoidmeasurement system complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The imaging sensor serves multiple functions: it captures images for object recognition, identifies characteristic image areas for speed determination, and provides environmental mapping. This multi-functionality eliminates the need for separate speed sensors and positioning systems, reducing overall system complexity while maintaining speed measurement capability.

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Measurement precision

If absolute positioning methods (balises, GPS, recognized landmarks) are used to determine vehicle location, then positioning accuracy is improved, but these methods are not continuously available

Engineering Contradiction:
Improvepositioning accuracyVSAvoidpositioning availability
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The system uses the imaging sensor to automatically identify characteristic image areas in the environment and compute vehicle position and speed autonomously. This self-service capability allows continuous positioning without relying on external infrastructure like balises or GPS, ensuring positioning availability in all operating conditions.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP4671084A1Method for determining the speed of a track-guided vehicle travelling on a route
Publication Date: 2025.12.31 SIEMENS MOBILITY GMBH
  • EP4671084A1 patent drawingFigure 1~2
  • EP4671084A1 patent drawingFigure 3~4
  • EP4671084A1 patent drawingFigure 5

AI summary

The invention encompasses the following: A method for determining the speed of a track-guided vehicle (FZ) traveling on a track. According to the invention, a sequence of images of the track and its surroundings is captured and stored by an imaging sensor, and the respective capture times of the images are stored in such a way that they are assigned to the respective images. Characteristic image areas are then identified in the images, and a number of stored images are selected to determine a perspective shift of at least one characteristic image area in the selected number of images, which arises due to the vehicle's movement. The perspective shift can then be converted into a speed, taking into account the capture times of the selected number of images.Furthermore, the invention comprises a vehicle (FZ) with a device for determining speed. Advantageously, a comparatively accurate relative location of the vehicle can be carried out when an absolute location of the vehicle is not possible.