Investigation of the clonk phenomenon in vehicle transmissions—measurement, modelling and simulation

Abstract

Vehicle drivelines with manual transmissions are exposed to different dynamic engine torques under driving conditions. Besides the excitation through the cyclic irregularity of the combustion engine, there are additional load change excitations, for instance during acceleration and deceleration. With load changes, transient vibrations and noise appear through the contact changes of free-travelling single components of the driveline. In this report a detailed theoretical modelling of the driveline will be presented after a short description of the measurement methods from a test rig. A comparison between the measurement and the calculation results has validated the simulation model. It is shown what effects the loose gears and the toothing clearance have on the angular acceleration of the transmission components. By means of model calculations it has been shown that the vibration behaviour of the test rig correlates well with that under actual driving conditions. Finally remedial measures have been worked out with this simulation tool.