Vehicle Liquid Fill Level Measurement Using Discrete Threshold Frequency Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for determining the fill level of liquids in vehicle containers, such as urea-water mixtures, are prone to inaccuracies due to dynamic movements and measurement noise, leading to unreliable liquid consumption calculations and potential manipulation detection challenges.

Innovation Solution

An operating method that uses a measuring device to assign measured fill levels to discrete thresholds, determines the frequency and duration of threshold activations, and calculates realistic fill values by identifying the threshold with the maximum frequency over a defined period, thereby filtering out noise and ensuring accurate liquid consumption assessment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If direct fill level measurement is used in dynamic vehicle conditions, then measurement simplicity is maintained, but measurement precision deteriorates due to movement-induced noise and inaccuracies

Engineering Contradiction:
Improvemeasurement system simplicityVSAvoidfill level measurement accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The continuous fill level measurement range is segmented into multiple discrete threshold levels. Instead of relying on a single continuous measurement that is susceptible to noise, the system divides the measurement space into distinct segments (thresholds), allowing the liquid level to be determined by identifying which segment it occupies. This segmentation approach filters out measurement noise while maintaining system simplicity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system employs periodic sampling of fill level measurements over time rather than relying on instantaneous readings. By taking multiple measurements at different time points and determining the most frequently occurring threshold activation, the system achieves more reliable results that are insensitive to transient noise caused by vehicle dynamics.

Inventive Principle:
Principle #19Periodic action

2Productivity

If instantaneous fill level readings are used for consumption calculation, then calculation speed is maintained, but reliability deteriorates due to noise and manipulation detection challenges

Engineering Contradiction:
Improveconsumption calculation speedVSAvoidliquid consumption measurement reliability
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The system performs preliminary processing of fill level measurements by comparing them against predefined thresholds and recording threshold activations before final consumption calculation. This preliminary action organizes the raw measurement data into a more reliable format (threshold activation frequencies) that can be quickly and reliably processed for consumption determination, ensuring both speed and reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system uses feedback from multiple measurement points and threshold activations to determine the most probable fill level. By analyzing the frequency distribution of threshold activations and selecting the most frequent occurrence, the system creates a self-correcting mechanism that filters out noise and potential manipulations, providing reliable consumption data for feedback control and monitoring purposes.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2562377B1Operating method for a vehicle
Publication Date: 2021.03.03 MAN TRUCK & BUS SE
  • EP2562377B1 patent drawingFigure 1
  • EP2562377B1 patent drawingFigure 2

AI summary

The operating method involves measuring a level (12) of a liquid in a tank of a vehicle by using a measuring unit, where the measured level is assigned to a nearest threshold level (10) among multiple of known threshold levels. Each threshold level is a defined filling value, where the threshold level among multiple of threshold levels is activated through measuring unit. The threshold level is determined relative to a defined period of a maximum frequency to represent a realistic filling value.