Fundamentals of Damping — Lesson 2

Damping is present in nearly every physical system.  If you look carefully you will see it in places you never realized.

Mountain biking is a sport enjoyed by many, and over the past few decades, the engineering of mountain bike suspensions has seen great innovations and improvements. Before the invention of suspension systems for mountain bikes, trying this type of maneuver would be pretty risky and likely not be pulled off as smoothly.

What is the magic that is helping to keep the ride from wiping out and crashing?  The suspension system is the key.  The first highlight shows the front and rear suspension.  Notice they are both elongated.  But the later highlights in the video show the rear suspension compressed, and then the front suspension compressed.   Watch again in full screen mode and see if you notice now.

Damping is the key to making this a smooth and less risky maneuver.  The suspension system has two main components, a spring and a damper.  The damper takes energy out, so the rider and bike don't bounce and lose control.

What types of physical damping are present in the mountain bike suspension?  One is viscous damping by a fluid-filled piston.  Another is an elastomeric (rubber) piece placed in the shock so that when the shock fully compresses it won't bottom out roughly; instead, it will push against the rubber to soften the blow of a hard landing. This is an example of material damping.

Lecture

In this video we will focus on the types of physical damping and then switch to how to characterize damping.  Let's get rolling.

Alternate video link.

Handout

Here are the accompanying handout slides for this lesson.