Vehicle Weight Estimation Using Air Spring Pressure Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing weight estimation devices for vehicles, particularly those using air springs in suspension systems, face complexity due to hysteresis effects, requiring multiple maps for accurate weight calculation which complicates the process.
Innovation Solution
A weight estimation device that includes a storage unit for weight calculation information correlating internal pressure values of air springs with vehicle height, a measured value acquisition unit, an internal pressure value calculation unit to correct measured values, and a weight calculation unit to determine the weight of the supported body based on corrected internal pressure values, simplifying the calculation process by using a single type of weight calculation information.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If two maps are used to correct internal pressure levels in response to suspension system expansion and contraction, then weight calculation accuracy is improved, but calculation process complexity increases
Solution Approach 1:
The patent merges the two separate correction maps (one for expansion, one for contraction) into a single correction map that handles both cases. The correction map stores correction values differentiated by suspension state (expanded/contracted), allowing the system to select and apply the appropriate correction value based on the current state without requiring separate map structures, thereby simplifying the overall system while maintaining accuracy
Solution Approach 2:
The patent introduces a dynamic state judgment mechanism that determines whether the suspension system is in an expanded or contracted state based on previous state information. This dynamic approach allows the system to adaptively select the appropriate correction value from the unified correction map, enabling accurate weight calculation across different suspension states without requiring multiple static maps
2Measurement precision
If multiple correction maps are used to account for hysteresis effects, then measurement precision is improved, but ease of operation deteriorates
Solution Approach 1:
The patent combines multiple correction maps into a single unified correction map that contains correction values for both expansion and contraction states. The map is structured to allow quick lookup based on suspension state, reducing the operational complexity of selecting and applying corrections while maintaining precision across different hysteresis conditions
Solution Approach 2:
The patent pre-calculates and stores correction values for both expansion and contraction states in advance within the unified correction map. This preliminary preparation eliminates the need for complex real-time calculations or multiple map selections during operation, simplifying the weight estimation process while maintaining accuracy
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 solution enhances the precision of weight calculation for vehicles by accounting for hysteresis effects without the need for multiple correction maps, thereby simplifying the calculation process and improving accuracy.
Implementation Method 1
air springs which configure a suspension system, the air springs supporting a vehicle body
Implementation Method 2
calculates the weight of a supported body supported by the air springs based on measured internal pressure level of the air springs
Implementation Method 3
The correspondence or relationship between the internal pressure level of the air springs and the weight of the supported body supported by the air springs changes in response to, if any, a hysteresis of an expansion and contraction of the suspension system
Data Source
AI summary
A weight estimation device for a vehicle includes a storage unit storing a weight calculation information indicating a correspondence between an internal pressure value of an air spring supporting a vehicle body and a vehicle height serving as a height of the vehicle body from a base, a measured value acquisition unit acquiring a measured internal pressure value and a measured vehicle height, an internal pressure value calculation unit calculating a corrected internal pressure value of the air spring by deducting or adding a corrected value from or to the measured internal pressure value in a case where the measured internal pressure value is greater or smaller than the internal pressure value of the weight calculation information which corresponds to the measured vehicle height, and a weight calculation unit calculating a weight of a supported body, including the vehicle body, based on the corrected internal pressure value.