Designing combat robots for the one-pound Plastic Antweight division has special considerations.

  • PET, PETG, ABS, or PLA, PLA+ are the only materials that can be used for the chassis and weapons.
  • Motors, electronics, axles, fasteners and adhesives can be any material, but cannot be used in such a way to enhance the structural integrity, armor the robot, or enhance any weapon.

Designing for the Plastic Antweight division

The Standardized Procedures for the Advancement of Robotic Combat lists several prohibited weapon and materials, both in general, and specifically for the Plastic Antweight class. The following sections are copied from OSCR's SPARC ruleset.

4.4.Plastic Classes

The spirit of these classes is to have an easy entry point for new builders and to encourage creative designs by limiting materials to plastics that are easy to work with, commonly used in 3D printers and don’t have strength characteristics common in the standard classes.

4.4.1.PET, PETG, ABS, PLA, or PLA+ are the only materials that can be used for the chassis and weapons. No other types of plastics or materials allowed (ie. metal, carbon fiber, UHMW, etc). At their discretion, event organizers may allow additional plastics that meet the spirit of the rules.

4.4.2.Non-plastic parts such as motors, electronics, axles, fasteners and adhesives can be any material, but cannot be used in such a way to enhance the structural integrity, armor the robot, or enhance any weapon. Magnets to enhance traction or downforce are prohibited. Foam is allowed for wheels and padding of electronics.

4.4.3.Robots may be disqualified at the Event Organizer’s discretion if it is deemed to violate the spirit of the class. Contact the event organizer ahead of time if you are not sure your robot meets the above definition.

14.Forbidden Weapons and Materials.

The following weapons and materials are absolutely forbidden from use:

14.1.Weapons designed to cause invisible damage to the other robot.

This includes but is not limited to:

14.1.1.Electrical weapons

14.1.2.RF jamming equipment, etc.

14.1.3.RF noise generated by an IC engine.

14.1.4.EMF fields from permanent or electro-magnets that affect another robot’s electronics.

14.1.5.Entangling Weapons or defenses:

These are weapons or defenses that can reasonably be expected to stop drive train and/or weapon motion by being wrapped around rotating parts.

This includes nets, tapes, strings, and other entangling materials or devices.

14.1.6.Weapons or defenses that that can reasonably be expected to stop combat completely of both (or more) robots.

14.2.Weapons that require significant cleanup, or in some way damages the arena to require repair for further matches.

This includes but is not limited to:

14.2.1.Liquid weapons.

Additionally a bot may not have liquid that can spill out when the robot is superficially damaged.

14.2.2.Foams and liquefied gasses

14.2.3.Powders, sand, ball bearings and other dry chaff weapons

14.3.Un-tethered Projectiles (see tethered projectile description in Special Weapons section 15.1)

14.4.Heat and fire are forbidden as weapons.

This includes, but is not limited to the following:

14.4.1.Heat or fire weapons not specifically allowed in the Special Weapons section (15.2)

14.4.2.Flammable liquids or gases

14.4.3.Explosives or flammable solids such as:

14.4.3.1.DOT Class C Devices

14.4.3.2.Gunpowder / Cartridge Primers

14.4.3.3.Military Explosives, etc.

14.5.Light and smoke based weapons that impair the viewing of robots by an Entrant, Judge, Official or Viewer.

(You are allowed to physically engulf your opponent with your robot however.)

This includes, but is not limited to the following:

14.5.1.Smoke weapons not specifically allowed in the Special Weapons section (15.3)

14.5.2.Lights such as external lasers above ‘class I’ and bright strobe lights which may blind the opponent.

14.6.Hazardous or dangerous materials are forbidden from use anywhere on a robot where they may contact humans, or by way of the robot being damaged (within reason) contact humans. Contact the event you plan to attend if you have a question.

15.Special weapon descriptions allowed at this event:

15.1.Tethered Projectiles are not allowed at this event.

15.2.Heat and Fire are not allowed at this event.

15.3.Smoke Effects are not allowed at this event.

The Plastic Antweight division hosts entirely 3d printed robot chassis and weapons which, as an additive process, has a few design considerations.

  • Print bed sizes are typically around 220mm x 220mm, and parts must fit inside the bed
    • Parts can be puzzle-pieced together with cutouts and exceed 200mm overall

    • Smaller parts print faster and are easier to replace

    • Be careful of overhangs, the printer cannot print on air!

  • Weight is the primary restraint in any combat robotics class

  • All 3d prints are comprised of the outermost surfaces called walls, and the interior space, or infill.

    • Infill is lighter than walls, so poking holes (Swiss-cheesing) adds weight by creating walls

      • Note in the following example how adding holes adds walls and weight to this cube

One of the exciting features of modern combat robotics is the ability to swap out parts for not only the sake of convenience in the pit stall, but to implement different offensive and defensive options. In order to do this, design tolerances to allow the correct fit.

Oregon State Combat Robotics covers these design elements, and more, during our weekly general meetings and workshops.