Torsional vibration

Torsional vibration is like playing with a Slinky. Imagine you have a long Slinky and you hold it at one end while someone else holds the other end. When you move your end up and down really quickly, the Slinky starts to move in a wavy pattern. This is similar to what happens inside a car or truck engine when it is running.

Inside an engine, there are a lot of parts that move together to make the car go. One of these parts is called the crankshaft. The crankshaft is like the skeleton of the engine. It is a long metal rod that connects all the other moving parts. When the engine is running, the crankshaft turns around and around very quickly, like a spinning top.

But, just like the Slinky, when the crankshaft spins quickly, it causes some wavy movements in the other parts of the engine. These waves are called torsional vibrations. They can make the engine shake and rattle a little bit, kind of like a bumpy car ride.

If torsional vibrations get really bad, they can cause damage to the engine. So, mechanics and engineers work hard to design engines that can handle these vibrations without breaking down.