Vehicle Acceleration Control Adjusting for Road Gradient
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle acceleration and deceleration control systems fail to adequately account for three-dimensional vehicle position changes relative to the road profile, leading to excessive uneasiness, such as a floating feeling, for occupants during travel.
Innovation Solution
An advanced drive system incorporating a forward information acquisition unit, position acquisition unit, and command calculation unit that adjusts drive commands based on road gradient and vertical acceleration limits (Gzmax) to minimize excessive forces during acceleration and deceleration, particularly when road gradients vary.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If acceleration and deceleration control is applied without considering three-dimensional vehicle position changes, then the control system remains simple, but the occupant experiences excessive uneasiness and floating feeling
Solution Approach 1:
The command calculation unit is designed to perform multiple functions: it calculates target speeds based on road gradient, determines drive commands considering both longitudinal acceleration and vertical acceleration constraints, and adjusts commands to prevent floating feelings. This multi-functional approach integrates three-dimensional control capabilities into an existing control architecture, achieving enhanced performance without proportionally increasing system complexity.
Data Source
AI summary
A forward information acquisition unit acquires a road profile ahead of the own vehicle. A position acquisition unit acquires a current position of the own vehicle. A state acquisition unit acquires a current speed of the own vehicle. A command calculation unit calculates a target speed at each point on a road ahead of the own vehicle, based on the road profile and the current position, and calculates a drive command for driving the own vehicle in the longitudinal direction of the own vehicle, based on the target speed and the current speed. The road profile includes a road gradient. The command calculation unit is configured to adjust the drive command, based on variation in the road gradient and Gzmax that is an acceleration limit limiting acceleration of the own vehicle in the vertical direction.