Engine Speed Control During Gear Shifts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current work vehicles face challenges in selecting appropriate engine speeds during gear shifting, leading to undesirable oscillations and increased fuel consumption, especially when operating in auto-efficiency or cruise control modes.
Innovation Solution
A system and method using a computing device to control engine and transmission operations, determining a measured gear ratio and calculating a desired engine speed based on the requested speed and gear ratios, ensuring the vehicle maintains the requested speed while minimizing fuel consumption by adjusting engine speed during gear shifts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If engine speed is selected to minimize fuel consumption at a given gear ratio, then fuel efficiency is improved, but during gear shifting the system cannot maintain optimal engine speed leading to increased fuel consumption
Solution Approach 1:
The controller determines a target engine speed in advance based on the upcoming gear ratio change, then executes the engine speed adjustment during the gear shift process. This preliminary planning ensures smooth transition and maintains optimal fuel efficiency throughout the gear shifting operation.
Solution Approach 2:
The system dynamically adjusts engine speed during gear shifting by continuously monitoring actual gear ratio changes and modifying the target engine speed accordingly. This dynamic adaptation allows the system to maintain optimal performance despite the transient conditions during gear transitions.
2Ease of operation
If engine speed is not properly controlled during gear shifting, then gear shifting can occur, but undesirable oscillations occur in the drivetrain leading to increased torque consumption and fuel usage
Solution Approach 1:
The controller applies preliminary counteracting action by determining and commanding a target engine speed that compensates for the expected drivetrain oscillations during gear shifting. This preemptive control prevents the oscillations from developing, maintaining drivetrain stability throughout the gear transition.
Solution Approach 2:
The system continuously monitors the actual gear ratio during shifting and uses this feedback to adjust the target engine speed in real-time. This closed-loop control ensures that engine speed adjustments remain synchronized with actual transmission behavior, preventing drivetrain oscillations.
3Reliability
If the system continuously monitors and adjusts engine speed during gear shifts, then vehicle speed maintenance and fuel efficiency are improved, but system complexity increases
Solution Approach 1:
The existing vehicle controller is enhanced to perform multiple functions: it continues to handle normal engine control while adding gear shift detection, target engine speed calculation, and active intervention during gear transitions. This multi-functionality approach maintains reliability without requiring completely separate control systems.
Solution Approach 2:
The system focuses on changing specific control parameters (engine speed targets) only during gear shift events rather than continuously monitoring all system parameters. This selective parameter adjustment maintains vehicle speed reliability while minimizing the increase in system complexity.
Data Source
AI summary
A method for determining and controlling engine speeds of a work vehicle during gear shifts may include controlling an operation of an engine and/or a transmission of a work vehicle so as to maintain the work vehicle operating at a requested speed, and determining a measured gear ratio for the transmission as a gear shift is occurring from a first gear ratio to a second gear ratio. The method may also include calculating a desired engine speed during the gear shift as a function of the requested speed and either the measured gear ratio or the second gear ratio. In addition, when the measured gear ratio differs from the first gear ratio by a predetermined threshold amount, the method may include controlling the engine speed based on the desired engine speed for a remainder of the gear shift from the first gear ratio to the second gear ratio.