Four-Wheel Drive Torque Distribution Control on Slopes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Four-wheel drive vehicles experience decreased uphill-driving ability and response speed when starting on an uphill slope due to uneven distribution of driving force between front and rear wheels, as the rear wheels receive less torque than needed to overcome increased loads.
Innovation Solution
A method that measures longitudinal acceleration to determine the slope degree of the ground and adjusts the torque distribution between main and sub-driving wheels using a power distribution device, providing increased torque to the rear wheels on uphill slopes and reducing torque based on brake signal and gear engagement times to prevent shock and maintain driver intention recognition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If driving force is distributed equally to front and rear wheels in four-wheel drive vehicles, then stability on slippery roads is improved, but uphill-driving ability decreases when starting on slopes due to insufficient torque to rear wheels
Solution Approach 1:
The patent implements dynamic torque distribution that adapts to driving conditions. The control unit dynamically adjusts the torque distribution ratio between front and rear wheels based on detected slope information, vehicle speed, and acceleration pedal operation amount. This resolves the contradiction by transitioning from static equal distribution to dynamic condition-based distribution, maintaining stability on slippery roads while providing enhanced uphill-starting capability when needed.
Solution Approach 2:
The patent changes the torque distribution parameter based on slope degree and driving conditions. When a slope is detected, the control unit increases the torque distribution ratio to the rear wheels, particularly during vehicle start on slopes. This parameter adjustment resolves the contradiction by optimizing torque allocation for different terrain conditions, ensuring both general stability and specific uphill-starting performance.
2Speed
If torque is increased to rear wheels on uphill slopes, then uphill-driving response speed is improved, but shock and instability may occur due to frequent torque adjustments
Solution Approach 1:
The patent applies preliminary action by detecting slope conditions in advance before the vehicle needs to start moving uphill. The control unit identifies uphill slopes through acceleration sensing and提前 (in advance) adjusts the torque distribution ratio to the rear wheels before the driver operates the acceleration pedal. This preliminary adjustment prevents shock during actual startup while maintaining fast response, as the system is already prepared with optimal torque distribution.
Solution Approach 2:
The patent implements feedback control by continuously monitoring vehicle acceleration, wheel speed, and slope conditions, then adjusting torque distribution accordingly. The control unit receives feedback from sensors and dynamically modifies the torque distribution ratio to maintain system stability while improving uphill response. This closed-loop control prevents excessive shock by making gradual, informed adjustments based on real-time vehicle state.
3Adaptability or versatility
If torque distribution is adjusted frequently to respond to changing slope conditions, then adaptability is improved, but device complexity increases due to multiple sensors and control mechanisms
Solution Approach 1:
The patent applies universality by designing a control unit that performs multiple functions: it detects slope conditions, calculates optimal torque distribution ratios, controls the power distribution device, and monitors vehicle state. This multi-functional approach resolves the contradiction by consolidating control logic into a single intelligent unit rather than requiring separate complex mechanisms for each function, thereby maintaining adaptability while managing system complexity.
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
Improves the uphill-driving response speed and ability by providing appropriate torque to the rear wheels based on slope level, reducing frequent torque adjustments, and minimizing shock in the four-wheel drive system.
Implementation Method 1
a measuring step that measures a longitudinal acceleration sensing value by a longitudinal acceleration sensor on a vehicle
Data Source
AI summary
A method of controlling traveling of a vehicle may include a measuring step that measures a longitudinal acceleration sensing value by a longitudinal acceleration sensor on a vehicle, a longitudinal acceleration calculating step that calculates a longitudinal acceleration of the vehicle from a speed of the vehicle, a slope degree calculating step that calculates a slope degree of a ground on which the vehicle is, from the longitudinal acceleration sensing value and the calculated longitudinal acceleration, a determining step that determines a slope direction and a slope level of the ground from the calculated slope degree, and a controlling step that provides in advance a torque amount, which is distributed from main driving wheels to sub-driving wheels for traveling, to a power distribution device, at different levels in accordance with the slope direction and the slope level of the ground.