Vehicle Spring Degradation Detection via Handling Characteristic Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing systems for diagnosing and controlling vehicle springs in suspension systems with active aerodynamic systems face challenges due to changes in spring characteristics over time or under excessive loading, leading to inaccurate tire loading estimates and suboptimal control of aerodynamic systems.
Innovation Solution
A method that involves sensing vehicle handling characteristics with mounted sensors, calculating first and second spring force estimated values using a Kalman Filter, and comparing these values to a threshold to adjust the nominal spring characteristic curve, ensuring accurate control of the active aerodynamic system by transforming it into an adjusted characteristic curve using a Recessive Least Squares Filter when necessary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the nominal spring characteristic curve is used to calculate tire loading, then the calculation is simple and fast, but the accuracy deteriorates over time as spring characteristics change
Solution Approach 1:
The system continuously monitors vehicle handling characteristics (accelerations, roll rates, pitch rates) and compares actual spring performance against the nominal characteristic curve. When degradation is detected through Kalman filtering and threshold comparison, the system provides feedback to adjust the spring characteristic curve, ensuring ongoing accuracy without requiring complex real-time reconstruction of spring properties
Solution Approach 2:
The system performs preliminary diagnosis by comparing estimated spring forces against the nominal characteristic curve before significant degradation affects tire loading accuracy. By detecting changes early through handling characteristic analysis and maintaining a library of spring characteristic curves, the system can proactively adjust parameters to maintain accuracy, preventing cumulative errors in aerodynamic control
2Adaptability or versatility
If spring characteristics are allowed to change with use and loading, then the spring adapts to operating conditions, but the nominal spring characteristic curve becomes inaccurate
Solution Approach 1:
The system dynamically adjusts the spring characteristic curve based on detected degradation patterns. Instead of using a fixed nominal curve, the system updates the characteristic curve parameters (spring rate, preload) based on comparative analysis of handling characteristics, allowing the model to adapt to actual spring behavior while maintaining measurement accuracy through continuous monitoring
Solution Approach 2:
The system changes the parameters of the spring characteristic curve (spring rate k, preload F0) based on detected degradation. By comparing estimated spring forces against the nominal curve and analyzing deviations in vehicle handling, the system identifies parameter changes and updates the characteristic curve to reflect current spring conditions, maintaining accuracy despite physical degradation
3Reliability
If vehicle handling characteristics are continuously monitored to detect spring degradation, then spring performance can be accurately diagnosed, but the computational load and system complexity increase
Solution Approach 1:
The system uses existing vehicle sensors (accelerometers, gyroscopes already present for other control functions) to monitor handling characteristics for spring degradation. By repurposing existing sensor data and computational resources already allocated for vehicle control, the system achieves reliable degradation detection without adding dedicated diagnostic hardware or excessive computational burden
Solution Approach 2:
The system replaces complex mechanical spring testing equipment with computational analysis of vehicle dynamics. Instead of physically testing spring properties, the system uses mathematical models (Kalman filtering) to estimate spring forces from measured handling characteristics, substituting mechanical measurement systems with software-based diagnostic algorithms
Data Source
AI summary
A method of controlling an active aerodynamic system of a vehicle includes calculating a first spring force estimated value from at least one sensed vehicle handling characteristic, and a second spring force estimated value from a nominal spring characteristic curve. When a difference between the first and second spring force estimated values is equal to or greater than a spring threshold value, a nominal spring characteristic curve is adjusted to define an adjusted spring characteristic curve, and the active aerodynamic system is controlled using the adjusted spring characteristic curve. When the difference between the first and second spring force estimated values is equal to or greater than the spring threshold value, a signal may also be engaged to provide a service recommendation.