Vehicle Bounce Motion Estimation Using Non-Linear Suspension Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for estimating bounce motion state quantities in vehicles assume linear suspension characteristics, leading to reduced accuracy when applied to non-linear vehicles.
Innovation Solution
A vehicle motion state estimation apparatus that includes a bounce motion estimation unit and a correction value estimation unit, which calculate and correct outputs based on non-linear suspension characteristics using traveling state information from general vehicle-mounted sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a linear suspension model is used for estimation, then the device complexity is reduced and ease of manufacture is improved, but the measurement precision of bounce motion state quantity is degraded when applied to non-linear vehicles
Solution Approach 1:
The patent applies dynamics by transitioning from a static linear suspension model to a dynamic non-linear model that adapts to varying suspension conditions. The non-linear model accounts for the changing relationship between vertical relative displacement and longitudinal displacement of wheels, allowing accurate estimation across different operating conditions while maintaining the same sensor configuration.
Solution Approach 2:
The patent changes the mathematical parameters of the suspension model from linear to non-linear characteristics. By modifying the model parameters to reflect the actual non-linear behavior of the suspension system, the estimation accuracy is improved without requiring additional sensors or hardware changes.
2Measurement precision
If a non-linear suspension model is used for estimation, then the measurement precision of bounce motion state quantity is improved, but the device complexity and computational requirements increase
Solution Approach 1:
The patent introduces a correction value as an intermediary element that bridges the gap between the simpler linear model and the more accurate non-linear model. This correction value compensates for the non-linear characteristics without requiring a complete overhaul of the estimation system, thus reducing the computational burden while maintaining accuracy.
Solution Approach 2:
The patent applies partial action by focusing only on the specific non-linear characteristics that most significantly affect bounce motion estimation. Rather than modeling all non-linearities of the suspension system, the approach targets the critical non-linear relationships between vertical and longitudinal wheel displacements, reducing computational complexity while preserving estimation accuracy.
Data Source
AI summary
Provided are a vehicle, a vehicle motion state estimation apparatus, and a method for estimating a vehicle motion state capable of highly accurately estimating a state quantity of a bounce motion of a vehicle having a non-linear suspension characteristic. The vehicle motion state estimation apparatus in a vehicle, in which wheels and a vehicle body are coupled via a suspension, includes a bounce motion estimation unit that estimates and outputs a state quantity of a bounce motion of the vehicle based on traveling state information of the vehicle, and a correction value estimation unit that calculates a correction value to correct an output the bounce motion estimation unit. The correction value estimation unit calculates the correction value in consideration of a non-linear characteristic of the suspension.