Vehicle Speed Control for Abrupt Road Grade Impact Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern vehicles with autonomous driving features struggle to provide a smooth ride over abrupt roadway grade changes, such as driving onto curbs, which can cause sudden stops, jolts, and discomfort to occupants, particularly for those with impairments or sensitivities.
Innovation Solution
A vehicle system that automatically detects abrupt grade changes using cameras or IMUs, determines a target speed for a comfortable transition, and adjusts vehicle speed through deceleration to maintain or achieve this target speed, thereby reducing impact loads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the vehicle maintains current speed over abrupt grade changes, then productivity is improved, but occupant comfort deteriorates due to sudden stops and jolts
Solution Approach 1:
The system detects abrupt grade changes ahead of time using cameras and IMU sensors, then proactively decelerates the vehicle before reaching the grade change. This preliminary action allows the vehicle to maintain smoother motion and reduce impact loads on occupants while still efficiently navigating the grade change.
Solution Approach 2:
The system dynamically changes the vehicle's speed parameter in response to detected grade changes. By adjusting speed from normal operating levels to reduced levels when grade changes are detected, the system balances productivity with occupant comfort, minimizing sudden stops and jolts.
2Object-affected harmful factors
If the vehicle decelerates to reduce impact load, then occupant comfort is improved, but productivity deteriorates due to reduced speed
Solution Approach 1:
The system performs deceleration in advance when grade changes are detected, allowing the vehicle to pass over the grade change at a controlled, comfortable speed. This timing optimization ensures that speed reduction is minimized while still achieving smooth passage, thereby balancing comfort with productivity.
Solution Approach 2:
The system dynamically adjusts vehicle speed based on real-time detection of grade changes. Rather than maintaining a fixed speed reduction, the system optimizes deceleration timing and magnitude to achieve the smoothest possible passage while minimizing overall travel time and productivity impact.
3Productivity
If the vehicle travels at higher speed, then productivity is improved, but measurement precision of grade changes deteriorates
Solution Approach 1:
The system performs grade change detection and analysis at lower speeds when conditions permit, ensuring high measurement precision. Once grade changes are identified and characterized, the system can then optimize subsequent passage speed to maintain productivity, using the preliminary precise measurements to guide safe and efficient traversal.
Data Source
AI summary
A method includes automatically monitoring a path in proximity to a vehicle to detect an abrupt grade change along the path and ahead of the vehicle. The grade change is determined to be abrupt depending on a predetermined threshold of a minimum change in grade height. Upon receiving, by processor circuitry forming at least one processor, indication that an abrupt grade change exists, the method determines a time or distance or both from a position of the vehicle to the abrupt change. The method then determines, by the processor, a target speed the vehicle is to use to travel over the abrupt grade change using predetermined correlations between a target speed of the vehicle and an indicator of expected comfort of an occupant of the vehicle as the vehicle travels over the abrupt grade change. The vehicle is decelerated to the target speed to drive over the abrupt grade change.