12lb Weight Class


12lb full combat robots up the amount of kinetic energy by an order of magnitude. These robots while still accessible by amateur and home builders, start to pack a serious punch. In this weight class you can expect to encounter lots of metal and steel. Very few plastic or 3d printed materials can handle the damage these bots can dish out.


  • All robots must have a weapon lock that prevents any weapons from moving outside of the cage.
  • All robots must have a way to turn off power without disassembling the robot.
  • All robots must pass a radio fail safe test.

Physical Rules


  • 12lbs in a fight ready condition. All robots will be weighed prior to their first match.
  • Any camera of video equipment weight can be excluded should you have a camera mounted to the robot
  • There is a 6lb weight bonus for robots that do not use wheels or tracks for motion
    • In the event you are building a multibot, only the heaviest robot needs to be without wheels.
  • There is a 3lb bonus for competitors made up for more than 1 robot.
    • If more than half of the total weight of the robots is disabled the whole robot is considered disabled
    • The maximum weight of any one bot is 110% the weight class limit (for 12lbs this is 13.2lbs.)
      • If that bot happened to not use wheels or tracks it it's maximum weight would be 18lbs (12+6lbs)
      • In order to achieve the no wheels / no tracks weight bonus only the heaviest bot needs to be without wheels
      • The heaviest robot in any multi-bot setup must have an active weapon
  • The weight bonuses may be combined for a maximum weight bonus of 7lbs (19lb total weight) (assuming a wheel-less multibot)


  • Robots must be able to fit in a 30"x30"x24" Box in a fight ready condition. The robots may expand or contract during the match


  • Robots must use electrical systems that operate at less than 72 volts



  • Robots must include at least one active weapon
  • Weapons which use fire or heat must be able to self light, and self extinguish.
    • They should also self extinguish in the event that the connection to the transmitter is lost.
    • A weapon is also considering self extinguishing if it flames out after 30 seconds from ignition
    • Matches may be stopped if video equipment is being damaged by fire
    • Competitors must demonstrate for safety the appropriate respect and precautions when working with flame or heat based weapons.
  • The following weapon types are prohibited
    • Nets
    • Projectiles over 150mph
    • Liquids of any kind
    • Weapons which purposefully disrupt radio signals
    • Strobe Lights
    • Lasers

Spare Batteries

Bringing Spare Batteries is HIGHLY encouraged. Bot's get a minimum of 20 minutes in between matches for repair and recharge. Rarely is this enough time to recharge a fully dead battery. Bringing spare batteries is highly recomended!! If you let the organizers know your battery size and connector type one week in advance (contact@50day.io), we will glady provide you with a spare battery for your bot for free. NHRL has a strong prefrence for XT style connectors XT90/60/30.


  • 4 People Max

Pushing the rules

These rules describe the absolute limits of what can be done. There is much that is allowed at NHRL that might not be at other events. We actively encourage competitors to think creatively and imagine new robot designs. The following are examples of things are are perfectly legal within the NHRL rules

You are ALLOWED to do this at NHRL

  • Robots that use fire or heat as weapon
  • Robots powered by an internal combustion engine
  • Robots that use compressed gasses
  • Robots that are made of fabrics or soft bodies
  • Robots that will keep fighting even if their batteries are on fire
  • Robots that are crusher robots
  • Robots that can fly