Rollover Predictor for Articulated Vehicles Using Yaw Rate
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rollover prediction systems for combination vehicles, such as articulated dump trucks, face challenges in accurately detecting lateral acceleration and rollover status, especially during large-roll-angle conditions, tire-slip/tire-lock, and understeering/oversteering, due to limitations in sensor detection and vehicle speed measurement.
Innovation Solution
A rollover predictor judgment device equipped with lateral acceleration sensors, yaw rate sensors, and steering-angle sensors that calculate and compare multiple lateral acceleration thresholds to determine the rollover status, enhancing detection accuracy and responsiveness across various vehicle states.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a lateral acceleration sensor is used to detect lateral acceleration of the rear vehicle body, then the rollover predictor status can be determined, but when the roll angle is large the sensor cannot correctly detect the lateral acceleration
Solution Approach 1:
The patent transforms the lateral acceleration detection problem into a parameter transformation problem. Instead of directly using the lateral acceleration sensor output, the system calculates lateral acceleration by transforming parameters from yaw rate and steering angle sensors through mathematical relationships (aL = r × ω²), where the transformation accounts for large roll angle conditions that invalidate direct sensor readings.
Solution Approach 2:
The patent introduces intermediary parameters (yaw rate and steering angle) that can be reliably measured even under large roll angle conditions. These intermediary measurements serve as mediators to indirectly determine lateral acceleration when direct measurement fails, bypassing the limitation of the lateral acceleration sensor.
2Measurement precision
If vehicle speed sensor and steering-angle sensor are used to calculate lateral acceleration, then rollover status can be assessed, but vehicle speed cannot be correctly detected when the tire is locked
Solution Approach 1:
The patent uses yaw rate as an intermediary parameter to bypass the unreliable vehicle speed measurement during tire lock conditions. By calculating lateral acceleration through the relationship aL = r × ω² (where ω is yaw rate), the system avoids directly using vehicle speed from sensors that fail under tire lock, maintaining detection reliability through an alternative measurement pathway.
Solution Approach 2:
The patent changes the measurement parameters from vehicle speed (which becomes unreliable under tire lock) to yaw rate (which remains detectable). This parameter substitution allows continuous and reliable lateral acceleration assessment regardless of tire lock status, transforming the detection approach to work under extreme conditions.
3Measurement precision
If multiple sensors and calculation methods are used to improve detection accuracy, then rollover predictor status can be accurately judged, but the device complexity increases
Solution Approach 1:
The patent makes existing sensors multi-functional by using yaw rate and steering angle sensors not only for their primary functions but also for lateral acceleration detection. This universal usage of existing components achieves improved detection accuracy without adding dedicated hardware, reducing the complexity increase that would normally accompany enhanced measurement capabilities.
Solution Approach 2:
The patent replaces direct mechanical/lateral acceleration sensing with a computational approach using rotational dynamics measurements. By substituting the lateral acceleration sensor's direct measurement function with calculations based on yaw rate and steering angle, the system achieves equivalent or superior accuracy while using sensors that remain reliable under diverse operating conditions.
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
The system effectively judges the rollover predictor status with high detection accuracy and responsiveness, even in challenging conditions, by using multiple lateral acceleration calculations and thresholds, ensuring timely notification and prevention of rollover events.
Implementation Method 1
a lateral acceleration sensor 26 that detects an acceleration of the rear vehicle body 3 in a right-left direction
Implementation Method 2
a yaw rate sensor 27 that detects a yaw rate of the rear vehicle body 3
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A rollover predictor judgment device (30) for a combination vehicle (1) includes a lateral acceleration sensor (26), a yaw rate sensor (27), an articulate angle sensor (23), and a judgment device in a form of a retarder controller (32). The judgment device judges that the combination vehicle is in a rollover predictor status when a first lateral acceleration calculated based on a detection value of the lateral acceleration sensor (26) is a first threshold or more or when a second lateral acceleration calculated based on a detection value of the yaw rate sensor (27) and a detection value of the articulate angle sensor (23) is a second threshold or more.