Tachograph Sensor Assembly Tamper Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing tachograph arrangements lack an independent verification mechanism to detect manipulations, relying on a single sensor for vehicle speed and state detection, which can be vulnerable to tampering.

Innovation Solution

Incorporating a second, adjacent sensor connected to a processing unit for generating digital data, with encrypted signals transmitted via the data line, allowing for independent verification without additional components or interface changes, and utilizing encryption and correlation processing for enhanced security.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single sensor is used for vehicle speed detection, then the device complexity is low, but the reliability is reduced due to vulnerability to tampering

Engineering Contradiction:
Improvetamper detection capabilityVSAvoidsensor arrangement complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent divides the sensing function into two separate sensors (first sensor and second sensor) that independently detect vehicle speed. This segmentation allows the system to compare readings from both sensors to detect tampering, thereby improving reliability while maintaining manageable complexity through modular sensor design

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent creates a redundant copy of the sensing function using a second sensor that mirrors the functionality of the first sensor. By having two independent sensors performing the same measurement task, the system can verify consistency between readings to detect manipulation, enhancing reliability without requiring fundamentally new sensor technology

Inventive Principle:
Principle #26Copying

2Reliability

If external sensors or additional components are integrated for verification, then the reliability improves, but the ease of manufacture and adaptability deteriorate due to interface modifications

Engineering Contradiction:
Improvesignal verification capabilityVSAvoidproduction process compatibility
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent designs the dual-sensor system to interface with the existing tachograph through standardized connections, allowing the same sensor arrangement to serve both original speed detection functions and the new verification function. This multi-functionality approach enables tamper detection without requiring separate interfaces or modifications to vehicle production processes

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

Solution Approach 2:

The system uses its own internal resources (the two sensors and their signal processing circuits) to perform verification, rather than relying on external systems like ABS or engine control units. This self-service approach eliminates the need for additional interface adaptations to external vehicle systems, maintaining ease of manufacture

Inventive Principle:
Principle #25Self-service

3Reliability

If encryption and digital signal processing are implemented, then the reliability and security improve, but the device complexity increases

Engineering Contradiction:
Improvesignal integrity verificationVSAvoidsignal processing circuit complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces physical signal transmission with digital signal processing and encryption. By converting analog sensor signals into digital form and applying cryptographic algorithms, the system achieves robust signal integrity verification and tamper detection. This substitution of mechanical/electrical signal handling with digital processing enhances reliability while the modular implementation keeps complexity manageable

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

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 provides robust protection against manipulation by offering an independent signal for plausibility checks, maintaining compatibility with standardized tachograph interfaces and enhancing security without altering vehicle architectures or production processes.

Implementation Method 1

the pulse generator includes a sensor element for generating a modulated electrical signal proportional to the vehicle speed

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP2306405B1Tachograph assembly for a vehicle and sensor assembly for a tachograph
Publication Date: 2019.05.22 CONTINENTAL AUTOMOTIVE GMBH
  • EP2306405B1 patent drawingFigure 1
  • EP2306405B1 patent drawingFigure 2
  • EP2306405B1 patent drawingFigure 3

AI summary

The tachograph arrangement has a tachograph and a sensor arrangement for detecting a parameter for driving condition of a vehicle. The sensor arrangement has two sensors (2,3), where the latter sensor is arranged adjacent to the former sensor. The former sensor is stand in connection with a digital data producing device (12). The digital data is produced directly or by an operating unit for operating sensor signals of the latter sensor.