Vehicle Height Control via Mass Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Commercial vehicles face challenges in maintaining a legally prescribed maximum height when unloaded, as tire deflation can cause the vehicle height to exceed limits, and existing solutions require additional sensors and complex systems for height adjustment.
Innovation Solution
A method using a mass estimator to determine the current mass of the vehicle based on sensed engine driving force, acceleration, and braking force, allowing for height adjustment through an air suspension system to maintain the vehicle below the maximum height without additional sensors, by estimating the mass and adjusting the ride height accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a level control valve with additional sensors is used to correct ride height, then the vehicle height can be controlled below the legal maximum, but the device complexity and cost increase
Solution Approach 1:
The existing sensor system serves dual purposes: it monitors both vehicle dynamics parameters (for mass estimation) and can be used for height control, eliminating the need for dedicated height sensors. The system uses itself to provide the required function without additional components.
Solution Approach 2:
The existing sensor network is designed to perform multiple functions: vehicle dynamics monitoring, mass estimation, and height control. This multi-functionality reduces the need for specialized sensors and simplifies the overall control system architecture.
2Measurement precision
If additional sensors are installed to measure ride height directly, then measurement precision improves, but the device complexity and cost increase
Solution Approach 1:
The existing sensor system monitors vehicle parameters (acceleration, driving force, braking force) that can be used to estimate mass and infer height changes. The system repurposes available sensors to provide height information without requiring dedicated height measurement sensors.
Solution Approach 2:
Direct mechanical/physical height measurement sensors are replaced with an indirect estimation approach using vehicle dynamics parameters. The mass estimator calculates height changes based on physics-based relationships between force, acceleration, and mass rather than direct geometric measurement.
3Reliability
If the vehicle height is adjusted to compensate for tire deflation, then the legal maximum height is maintained, but energy consumption increases
Solution Approach 1:
Instead of continuously adjusting height, the system activates height correction only when mass changes indicate significant tire deflation. This partial action approach maintains legal compliance while minimizing energy consumption by avoiding unnecessary adjustments.
Solution Approach 2:
The system continuously monitors vehicle mass and height, activating height adjustment only when the estimated mass change indicates tire deflation that would cause height exceedance. This feedback-based approach optimizes energy usage by correcting height only when necessary for compliance.
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 method simplifies height adjustment by utilizing existing data sources, reducing the need for additional sensors and ensuring the vehicle remains below the legal maximum height, even when empty, thereby preventing height exceedance due to increased tire radius.
Implementation Method 1
a height-adjustable motor vehicle... air suspension system... adjusting a height (eg, ride height) of the motor vehicle
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a method for adjusting the height of a height-adjustable motor vehicle (10), preferably a commercial vehicle. The method includes determining the current mass, preferably the current total mass, of the motor vehicle (10) using a mass estimator. The method includes adjusting the height of the motor vehicle (10) based on the determined current mass of the motor vehicle (10). Preferably, the current total mass can be estimated very easily using the mass estimator, which can provide information about the height of the motor vehicle.