Vehicle Guidance System Wheel Angle Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vehicle guidance systems rely on costly wheel sensors for wheel angle estimation and hardcoded steering ratios, which are inflexible and require manual adjustments, leading to increased costs and reduced performance.
Innovation Solution
A vehicle guidance system that uses a processor to estimate wheel angles based on hand wheel angle and yaw rate, adjusting steering commands to guide the vehicle along a set path, eliminating the need for wheel sensors and allowing dynamic adjustment of steering ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If wheel sensors are attached to each wheel to estimate wheel angle, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent extracts the wheel angle estimation function from physical wheel sensors and implements it through a computational model using readily available sensor data (steering wheel angle sensor, vehicle speed sensor, yaw rate sensor). This eliminates the need to attach sensors to each wheel while maintaining estimation capability.
Solution Approach 2:
Instead of directly measuring wheel angle with physical sensors on each wheel, the patent creates a computational copy/estimate of the wheel angle by processing data from existing sensors through a mathematical model. This virtual sensing approach achieves the measurement function without the physical complexity.
2Measurement precision
If wheel sensors are attached to each wheel to estimate wheel angle, then measurement precision is improved, but cost increases
Solution Approach 1:
The patent makes existing sensors (steering wheel angle sensor, vehicle speed sensor, yaw rate sensor) perform multiple functions. These sensors originally designed for other purposes are now also used for wheel angle estimation, eliminating the need for additional dedicated wheel sensors and reducing overall system cost.
Solution Approach 2:
The system uses its own existing sensor infrastructure to provide the wheel angle estimation function. Rather than requiring external wheel sensors, the vehicle's existing sensor network serves the additional function of enabling accurate wheel angle estimation through computational processing.
3Ease of manufacture
If hardcoded steering ratio is used in control systems, then ease of manufacture is improved, but adaptability deteriorates
Solution Approach 1:
The patent transforms the static, hardcoded steering ratio into a dynamic, estimable parameter. By implementing a steering ratio estimation module that calculates the actual steering ratio based on measured data, the system can adapt to different vehicle configurations and conditions while maintaining ease of manufacture through software-based flexibility.
4Manufacturing precision
If manual adjustment of gains is required to improve vehicle performance, then ease of operation deteriorates, but manufacturing precision can be maintained
Solution Approach 1:
The patent implements feedback mechanisms where the estimated wheel angle and steering ratio are continuously used to adjust and optimize vehicle guidance control. The system automatically uses the estimated parameters to refine steering commands, eliminating the need for manual gain adjustment while maintaining precise vehicle performance control.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In an example embodiment, a vehicle guidance system includes a memory including computer-readable instructions stored therein and a processor. The processor is configured to execute the computer-readable instructions to estimate a wheel angle of a vehicle based on at least a first value, the first value being a hand wheel based estimate of the wheel angle, and adjust steering commands for steering the vehicle based on the estimated wheel angle to permit the vehicle to move along a set path.