Vehicle Mass and Road Grade Estimation via Uncertainty Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for estimating vehicle mass and road grade during operation are inadequate, impacting fuel economy and drivability, and lack precision and reliability.
Innovation Solution
A vehicle system that uses a controller to estimate vehicle mass and road grade by integrating sensor data, including engine torque, power loss, and navigation information, with uncertainty calculations to adjust engine output and speed, employing modules like vehicle mass estimation, power loss estimation, and road load variance estimation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If vehicle mass and road grade are estimated using existing methods, then fuel economy and drivability are impacted, but the estimation accuracy and reliability are insufficient
Solution Approach 1:
The system continuously monitors vehicle operation parameters and updates mass and road grade estimates in real-time based on feedback from vehicle dynamics. The controller compares estimated values with actual vehicle behavior and adjusts estimates accordingly, improving both accuracy and reliability through closed-loop feedback control.
Solution Approach 2:
The system dynamically changes estimation parameters based on operating conditions. Different estimation algorithms and weightings are applied depending on vehicle speed, acceleration, and load conditions, allowing the system to adapt to varying scenarios and improve estimation reliability across different operating ranges.
2Productivity
If real-time vehicle mass and road grade estimation is implemented, then fuel efficiency and drivability improve, but system complexity increases
Solution Approach 1:
The control module serves multiple functions: it manages engine operation, performs vehicle mass estimation, determines road grade, and controls transmission shifting. By consolidating these functions into a single multi-functional controller, the system achieves improved fuel efficiency without proportionally increasing overall system complexity.
Solution Approach 2:
The system uses existing sensor data from the vehicle's normal operation (acceleration, speed, engine torque) to perform mass and road grade estimation without requiring additional dedicated sensors or complex hardware infrastructure. The vehicle's own operational data serves the dual purpose of control and estimation.
3Measurement precision
If uncertainty evaluation is performed on vehicle mass estimate, then road grade estimation accuracy improves, but computational requirements increase
Solution Approach 1:
The system performs uncertainty evaluation selectively rather than continuously. Road grade estimation is initiated only when vehicle operating conditions are suitable (e.g., during coasting or specific acceleration patterns), and uncertainty thresholds are used to determine when estimation is necessary, reducing unnecessary computational overhead while maintaining accuracy when needed.
Data Source
AI summary
Apparatuses, methods and systems including dynamic estimations of vehicle mass and road grade estimation are disclosed. One exemplary embodiment is a method including operating a vehicle system to propel a vehicle, determining with a controller a vehicle mass estimate and an uncertainty of the vehicle mass estimate, evaluating with the controller the uncertainty of the vehicle mass estimate relative to at least one criterion, if the uncertainty of the vehicle mass estimate satisfies the criterion, determining with the controller a road grade estimate, and controlling with the controller utilizing the road grade estimate at least one of a vehicle speed and an engine output.