Transmission Control Device for Corner Exit Drivability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle transmission control systems face challenges in maintaining actual vehicle speed alignment with target speed patterns, particularly on inclined corners and slopes, leading to reduced drivability and insufficient acceleration performance, while also failing to optimize fuel consumption during deceleration phases.
Innovation Solution
A transmission control device that includes a shift timing calculation unit, a target gear ratio calculation unit, and a gear ratio overwriting command unit to adjust the gear ratio based on external information, ensuring the vehicle accelerates at the correct position and maintains the required gear ratio for improved drivability and reduced fuel consumption during deceleration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the gear ratio is changed from deceleration section to acceleration section based on fuel consumption optimization, then fuel consumption in deceleration section is reduced, but acceleration performance at exit of corner is insufficient
Solution Approach 1:
The control device determines an acceleration position in advance before the vehicle reaches the exit of the corner, and sets the gear ratio to approach the required gear ratio at this predetermined position. This preliminary adjustment ensures that when the vehicle actually needs acceleration at the corner exit, the transmission is already in the optimal gear ratio state, thus maintaining both fuel efficiency during deceleration and acceleration performance at the exit.
2Use of energy by moving object
If the gear ratio is set for flat road conditions, then fuel consumption is optimized, but actual vehicle speed deviates from target speed pattern on inclined corners
Solution Approach 1:
The control device calculates a required gear ratio that specifically accounts for corner inclination angle. When the corner is inclined, the system adjusts the gear ratio parameters differently from flat road conditions. The gear ratio is controlled to approach this inclination-compensated required gear ratio at the determined acceleration position, ensuring that the actual vehicle speed follows the target speed pattern accurately even on inclined corners while maintaining fuel efficiency.
3Power
If the acceleration gear ratio is determined only for acceleration section, then acceleration performance is improved, but fuel consumption reduction in deceleration section is not achieved
Solution Approach 1:
The control device continuously monitors the vehicle's position relative to the corner and determines the optimal acceleration position based on the distance from the corner exit. The gear ratio control is adjusted continuously to approach the required gear ratio as the vehicle approaches the acceleration position, rather than making abrupt changes. This continuous adjustment ensures smooth transition that maintains acceleration performance while optimizing fuel consumption during the deceleration section leading up to the corner.
Data Source
AI summary
Provided is a transmission control device which can improve drivability in an acceleration section even while taking a reduction of fuel consumption in a deceleration section into consideration. The transmission control device (transmission controller) which controls a transmission in a running control of a vehicle includes a shift timing calculation unit which determines an acceleration position at which the vehicle accelerates on the basis of a target speed pattern generated from external information, a target gear ratio calculation unit which determines a required gear ratio which is required at the acceleration position, and a gear ratio overwriting command unit which outputs a command of overwriting the gear ratio such that the gear ratio at the acceleration position approaches the required gear ratio. In the control of the transmission of the transmission controller, the gear ratio is set to the required gear ratio (target gear ratio) at a predetermined point after the vehicle exits the deceleration section and reaches the acceleration position.