Tabletop Pull Back Tri-Mode Spring Motor Rolling Chassis is a fully 3D printed rolling chassis having 3 modes of operation, wind, power and coast.
My earlier 3D printed windup vehicles used a key or knob to wind the spring. This vehicle uses a floating pinion gear designed to wind the spring when the the vehicle is rapidly rolled backwards. This is the wind mode.
Once the spring is wound, releasing the vehicle propels it forward until the spring is depleted of its stored energy. This is the power mode.
Finally, after the spring is depleted, a second floating pinion gear disengages the spring motor from the rear axle allowing the vehicle to coast. This is the coast mode.
This vehicle does not outperform my earlier designs for distance, but it does illustrate that there's always room for improvement!
I probably forgot a file or two or something, so if you have any questions, please feel free to ask.
Designed using Autodesk Fusion 360, sliced using Cura 2.3.1, and printed in PLA on an Ultimaker 3 Extended.
You will need to purchase 12 "AS 568" size 221 (1 11/16 O.D., 1 7/16 I.D., 1/8" section) o-rings for the tires.
I printed my parts on an Ultimaker 3 Extended using .1mm vertical resolution and 100% infill for "Axle Spring.stl", "Spring.stl", "Gear Spring.stl" and "Axle Rear.stl", the remaining parts at 20% infill.
Prior to assembly, test fit and trim, file, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on the colors you chose and your printer settings, more or less trimming, filing and/or sanding may be required. Carefully file all edges that contacted the build plate to make absolutely sure that all build plate "ooze" is removed and that all edges are smooth. I used a flat jewelers file and plenty of patience to perform this step.
Study "Assembly.stl", carefully noting the locations and positions of the various components as assembly proceeds.