This is the result of an invitation for our department to be involved in an Engineering sponsored Sumo-bot competition. The rules are fairly simple.
- Maximum weight is 12 lbs
- Maximum voltage is 16
- Maximum size not to exceed 600 mm in X, Y, and Z.
- No pneumatic or hydraulic components
- Offensive device energy limited to throwing or flipping limited to 600 mm high or 600 mm distance
Represented here is basic platform for mounting defensive and offensive systems to. This part of the project is ongoing and has been revised several times, though the basic design has been to make it a defensive design from the beginning.
Available here https://armattanproductions.com/pages/kit_detail/1644 are prefabricated upper, lower, and inner side panels from 3mm carbon fiber.
Most everything has been printed with 4 upper and lower layers as well as perimeters. Infill has been 30% for most parts with the exception of the battery housing and its parts that were printed at 100% infill. Small parts such as spacers are also at 100%.
Print temperatures have been 225C on the hot end and 55C on the bed. All parts are in PLA from www.microcenter.com. There is a store locally, and they have the best price on PLA.
Specifications and Sources
Wheels and Tires
Just a note about the three different drive wheel files;
This is the original wheel design concept. You simply run a 3/8-24 tap inside and the wheel threads directly on the the output shaft of the gearbox. Then install the LH retaining screw that you removed when uninstalling the chuck from the cordless drill. The retention method is sound and secure if you are not driving too hard.
This wheel is the same concept as above except for 1.9 mm is removed from the back face to accommodate the variations in cordless drill models offered at Harbor Freight.
This is the improved design that also requires a lathe turned piece that makes the threads secure. I found that aggressive driving led to wearing on the plastic threads. I will post a pdf file detail sheet to manufacture the metal hub part to.