Downhill Shifting Control Using Gravity Sensor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shifting control methods for vehicles fail to recognize downhill grades before entering the grade, leading to inefficient fuel usage and unstable driving experiences due to inappropriate shifting modes during coasting operations.
Innovation Solution
A shifting control method and apparatus that collect forward road grade information and determine the appropriate shifting mode based on the downhill grade before the vehicle enters the section, allowing for preemptive control of the transmission between coasting neutral control and D-stage shift control modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the transmission is maintained at drive gear mode (D stage) during coasting operation, then the engine brake can be operated to control vehicle speed, but the vehicle durability is degraded and ride quality is worsened due to engine acting as a load
Solution Approach 1:
The system performs preliminary grade recognition using a gravity sensor before the coasting operation begins, allowing the control device to pre-determine the appropriate shifting mode. This prevents the need to switch modes during coasting, avoiding engine brake engagement and protecting vehicle durability while maintaining speed control.
Solution Approach 2:
The transmission shifting mode is made dynamic and adaptive based on the recognized road grade. The control device automatically selects between neutral mode and D-stage mode according to the gravity sensor data, optimizing both speed control and vehicle durability for different downhill conditions.
2Speed
If the transmission is maintained at drive gear mode (D stage) during coasting operation, then vehicle speed can be controlled, but the coasting distance is reduced and reacceleration frequency increases
Solution Approach 1:
The system performs preliminary grade recognition using a gravity sensor before the coasting operation begins, allowing the control device to pre-determine the appropriate shifting mode. This prevents the need to switch modes during coasting, avoiding engine brake engagement and protecting vehicle durability while maintaining speed control.
Solution Approach 2:
The transmission shifting mode is made dynamic and adaptive based on the recognized road grade. The control device automatically selects between neutral mode and D-stage mode according to the gravity sensor data, optimizing both speed control and vehicle durability for different downhill conditions.
3Use of energy by moving object
If the transmission is shifted to neutral mode during coasting operation on downhill with steep grade, then coasting distance can be increased, but the vehicle speed is rapidly increased making the driver feel uneasy
Solution Approach 1:
The system performs preliminary grade recognition using a gravity sensor before the coasting operation begins, allowing the control device to pre-determine the appropriate shifting mode. This prevents the need to switch modes during coasting, avoiding engine brake engagement and protecting vehicle durability while maintaining speed control.
Solution Approach 2:
The transmission shifting mode is made dynamic and adaptive based on the recognized road grade. The control device automatically selects between neutral mode and D-stage mode according to the gravity sensor data, optimizing both speed control and vehicle durability for different downhill conditions.
4Measurement precision
If the grade is recognized after the vehicle enters the downhill section, then the control decision can be made based on actual grade, but the control response is delayed and proper control cannot be performed at the appropriate point in time
Solution Approach 1:
The system performs preliminary grade recognition using a gravity sensor before the coasting operation begins, allowing the control device to pre-determine the appropriate shifting mode. This prevents the need to switch modes during coasting, avoiding engine brake engagement and protecting vehicle durability while maintaining speed control.
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
This approach improves fuel efficiency and provides a stable driving experience by enabling proper shifting control before entering a downhill grade, reducing reacceleration frequency and maintaining vehicle speed, thereby enhancing overall driving performance.
Implementation Method 1
the driver may recognize the grade of a downhill on which the vehicle is currently traveling, using a gravity sensor (G sensor)
Data Source
AI summary
A shifting control method for controlling a speed change of a vehicle in a downhill section may include collecting, by a forward road grade information collection device, information on a downhill grade which is present ahead of a vehicle, before a vehicle enters a downhill section, determining, by a driving information detection device, whether a predetermined inertial driving condition is satisfied, before the vehicle enters the downhill section, and deciding, by a control device, a shifting mode of the vehicle depending on the downhill grade, and controlling a transmission according to the decided shifting mode, at a predetermined time before the vehicle enters the downhill section.