Gearshift Parameter Optimization for Cab Vibration Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Commercial vehicle driver's cab experiences uncomfortable pitching movements during traction force interrupted gear shifts due to vibrations, which can lead to shocks against limiting stops, and existing solutions either make shifts highly noticeable or result in uncomfortable stiff suspensions.
Innovation Solution
A method using a mathematical model to simulate and optimize traction force shift parameters, such as traction force reduction and increase times, to minimize vibration amplitudes, coupled with a control device for implementing these parameters, considering the vehicle's movement equations and geometric parameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a soft suspension is used for the driver's cab, then driver comfort is improved, but pitching movements during gear shifts become highly noticeable and cause shocks against limiting stops
Solution Approach 1:
The patent applies parameter changes by optimizing the traction force gradient (rate of change of traction force) during gear shifts. Instead of changing the suspension stiffness, the invention modifies the temporal profile of traction force application - specifically controlling how quickly traction force increases or decreases during shifting. By adjusting this parameter, the excitation of pitching movements is reduced, allowing soft suspensions to maintain comfort without excessive vibrations or shocks against limiting stops.
2Object-affected harmful factors
If a stiff suspension is used for the driver's cab, then pitching movements during gear shifts are reduced, but driver comfort deteriorates
Solution Approach 1:
The invention changes the approach from modifying suspension parameters to modifying traction force parameters. By controlling the rate of change of traction force (traction force gradient) during gear shifts, the system reduces pitching movements without requiring stiff suspensions. This allows the use of soft, comfortable suspensions while still minimizing harmful vibrations through optimized force application timing and rate.
3Speed
If traction force is rapidly changed during gear shifts, then shifting speed is improved, but vibration amplitude of the driver's cab increases
Solution Approach 1:
The patent applies parameter changes by optimizing the traction force gradient - the rate of change of traction force during shifting. Instead of simply increasing shifting speed through rapid force changes, the invention controls the temporal profile of traction force application. By adjusting this parameter, the system achieves fast shifts while limiting the excitation of vibrations, thus reducing cab vibration amplitude even during rapid gear changes.
4Object-affected harmful factors
If traction force gradient is reduced to minimize vibrations, then driver comfort is improved, but shifting time increases
Solution Approach 1:
The invention optimizes the traction force gradient parameter to achieve a balance between shifting speed and vibration reduction. By carefully controlling the rate of change of traction force, the system minimizes vibration excitation without excessively prolonging the shift duration. This optimized parameter allows for relatively fast shifts while keeping vibration amplitudes at acceptable levels, resolving the trade-off between shifting time and driver comfort.
Data Source
AI summary
A method of parameterization of traction force interrupted shifts in a transmission of a commercial vehicle having a frame, a cab supported by the frame, and a trailer coupled to the frame. The method includes a mathematical model which considers movement equations and geometrical parameters of the frame, the cab, and the trailer. Traction force patterns of traction force interrupted shifts are predetermined which depend on a traction force decrease time, a shift time, and a traction force increase time. From model and force patterns, vibration behaviors of the cab as the output parameter of the model is simulated. The parameterization of traction force interrupted shiftings takes place such that, as the shifting parameters, the traction force decrease time, the shift time, and the traction force increase time of such force patterns are determined, for which a defined evaluation criterion of the simulated vibration behavior of the cab is optimal.