Overview
This is a flat front shovel for the Makerbot mBot robot to be used for robot fighting in a sumo arena.
The stock mBot’s bare front bumper is not built for pushing other robots around a sumo ring, so a proper front-end attachment is one of the first upgrades worth printing before a competition. This version uses a flat front edge, which gives the robot a wide, solid contact surface for head-on pushing matches, rather than one that tries to slide underneath an opponent. It is a simple, direct approach that works well against robots with a low, wedge-shaped front, where getting underneath them is not really an option anyway.
The shovel includes a shroud that protects the infrared sensors from sunlight, helping them better sense the boundaries of the battlefield. That shroud matters more than it looks: mBot’s line sensors read reflected infrared light to detect the white boundary line of the arena, and under bright competition lighting or sunlight, stray light easily washes out that reading and causes a robot to drive straight out of bounds. Shielding the sensors keeps the robot reacting to the actual ring edge instead of ambient glare.
I also designed a curved front shovel alongside this flat one, since the best shape often depends on your opponents’ style and the specific rules of the competition you are entering. Printing both and testing them against each other is the easiest way to find out which one suits your mBot best.
Both shovels bolt onto the same stock mounting points on the mBot chassis, so switching between them between matches takes a couple of minutes and no permanent modification to the robot itself. If your local competition rules restrict certain shapes or dimensions, it is worth checking those before committing to either version.
Sumo rules and opponent styles vary a lot between events, so it is worth treating both shovel shapes as a starting point to test against rather than assuming one is objectively better than the other for every match.
A cheap kit robot with the right printed attachments can hold its own against far more expensive hardware.
A simple upgrade that turns a kit robot into a real sumo contender.
I would generally reach for the flat shovel first against an opponent I have not fought before, since a wide, direct pushing surface is the more forgiving choice when you do not yet know how the other robot’s front end is shaped.
Download
The model is free to download and print, licensed under the Standard Digital File License.