See the Slow Roller in action here:
These are the 3D printed parts for a Slow Roller apparatus to be used in a physics class. In addition to these parts you need two or four equal lengths of 1/2-inch electrical conduit and something to elevate the upper stand (I use two or three textbooks).
With the ramp assembled at a small angle the rollers accelerate at a very slow rate, allowing students to accurately measure displacement and time data.
I have students plot displacement vs time, which results in a quadratic relationship. This is a wonderful opportunity to teach students how to linearize data. You can also calculate a few tangents of the displacement graph in order to produce a velocity vs. time graph, from which students can determine the acceleration of the rollers.
The Disk Roller and the Ring Roller accelerate at different rates, allowing you to create various challenges for students. The Long Island Physics Teachers Association uses this apparatus in one of the events at their annual Physics Olympics. A challenge might be for students to predict where faster roller will overtake the slower roller when the slower roller is released with a head start on an adjacent track.
Rollers
I print the rollers with 50% infill.
Stands
I print the stands with 15% infill.
The author hasn't provided the model origin yet.