Automated Manual Transmission Clutch Control for Low Speed Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automated mechanical transmission systems in heavy construction vehicles face unpredictability in clutch and engine response to minimal throttle requests, making precise low-speed positioning and pacing challenging.
Innovation Solution
A control method for an automated manual transmission system that determines the rate of throttle change to engage the clutch at distinct rates, allowing for normal or blended pedal modes, where the clutch can be partially slipped to control engine speed and vehicle movement incrementally, enabling precise positioning and pacing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the clutch is engaged at a normal engagement rate for typical acceleration, then the vehicle responds quickly to throttle input, but the vehicle cannot achieve precise low-speed positioning and pacing
Solution Approach 1:
The clutch engagement rate is made dynamic and adaptive based on operating conditions. The control system adjusts the clutch engagement rate between a first rate for normal acceleration and a second rate for low-speed positioning, allowing the system to optimize performance for different operational requirements rather than using a fixed engagement rate
2Speed
If minimal throttle request is applied for incremental vehicle movement, then low-speed positioning is attempted, but the clutch and engine response becomes unpredictable
Solution Approach 1:
The control system incorporates feedback mechanisms to monitor clutch slip and throttle pedal position. Based on this feedback, the system determines whether to maintain blended pedal mode or transition to normal clutch mode, thereby improving the reliability of clutch response during minimal throttle requests by continuously adapting to actual operating conditions
3Productivity
If the clutch is engaged at a high engagement rate, then the vehicle accelerates rapidly, but the vehicle cannot move incrementally for precise positioning
Solution Approach 1:
The system changes the clutch engagement rate parameter based on the operational mode. In blended pedal mode, a second clutch engagement rate is used that allows incremental vehicle movement for precise positioning. When normal acceleration is required, the system switches to a first clutch engagement rate that provides rapid acceleration, thus adapting the parameter to meet different performance requirements
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
The system allows for accurate and controlled low-speed vehicle positioning and pacing by engaging the clutch proportionally with throttle pedal movement, reducing unpredictability and maintaining steady engine power for applications like cement mixers.
Implementation Method 1
a clutch drivingly interposed between the engine and an input shaft of the transmission... The clutch is engaged at a first clutch engagement rate... The clutch is engaged at a second clutch engagement rate
Data Source
AI summary
A control method for operating an automated manual transmission system having a fuel-controlled engine, a multiple-speed change-gear transmission and a clutch drivingly interposed between the engine and an input shaft of the transmission is provided. The control method determines a rate of throttle change of a throttle pedal. The clutch is engaged at a first clutch engagement rate based on the rate of throttle change being greater than a threshold. The clutch is engaged at a second clutch engagement rate in a blended pedal mode that is proportional to an amount of throttle percentage engagement based on the rate of throttle change being less than the threshold. The first and second clutch engagement rates are distinct.