

Now some of you are probably wondering, “well why can’t we just replicate the output of an engine?”. Well, you are on to something, but unfortunately it is a bit more difficult than you might think. Imagine rotating a tube at constant speed, and while the tube is rotating add a jittering movement. The difficulty is being able to cause and impose the torsional pulsations onto the component in a very short timeframe, since the engine speed will rotate between 10 and over 100 times per second, so the pulsation required must occur within about one thousandth of a second. To do this a large torque is required to accelerate the drive shaft (representing the crankshaft) in the clockwise and anticlockwise directions while the component under test is being rotated at a nominal speed.

At ATA, we are developing a new module to simulate torque pulsations. We have researched the market and there are torque pulsation systems out there, but these were typically developed for measuring torque out-of-balance of power generation turbines that have shafts with diameters in the order of 200 mm. These machines are extremely expensive and are not well-suited for automotive applications. Our new module has been specifically designed to recreate the torsional vibrations an automotive combustion engine would enact on a powertrain component. For example, an engine oil pump will be able to function by pumping oil in its normal operating mode, while at the same time experiencing torsional vibrations on it's drive shaft.