300 Gram Combat Robot Details

This information is no longer current, we now use rules for 1 pound and 3 pound robots. See our main page for more info.

Our Own Weight Class
Due to the fact that building a 150 gram fighting robot is a little difficult to say the least, and our goal is to get as many people interested as possible in this sport. We have designed our own weight class and rules. Once we have a bigger space and battlebox we plan on a 3lb weight class but for now, please build according to the following rules.

Bot building rules –
300 Gram max weight
bot has to fit in a 6x6x6″ cube (think diagonal you can get a bot bigger than 6×6″)
Battery MUST be enclosed inside the bot
No – flames, liquids, electro-shock, electromagnets, entangling devices or projectiles allowed.
You must have a screw in style power button – plans for how to build one are on https://www.thingiverse.com/thing:3081171 (yours does not have to be this one but needs to function like it. – no switches)
Bot must have a safety built in that if the transmitter is not connected, the bot disables. (this feature is built into almost all modern controller and receivers and is on by default)

Battle Rules
Bot weapons can ONLY be tested inside the battle box with the door shut
rounds are 3 min long
Each bot starts on either a red or blue square
You will hit your ready button when you are ready – no take backs!
Immediately after both opponents hit their ready buttons a count down will take place via color changing lights. – RED, YELLOW, GREEN – bell will ring and battle begins.
after 45 seconds the lights on the box will change to yellow for 15 seconds.
after those 15 seconds, the Blue and Red trap doors will open
At the 2min 45 second mark the white lights will start to fill in with yellow. Once all lights are yellow bell will ring and lights will turn red signifying the end of the round.
at the end of the round bots MUST be turned off before the door can be opened.
Winner is determined by one of 3 things. –
Disable opponents bot – if the bot cannot move transversely (spinning in a circle does not count) or bot driver can surrender.
Push opponents bot into the trap doors holes – If both bots fall through the bot that went through last is the winner. If it is determined that both bots fell through at the exact same time, it will go to a judges decision.
Judges decision – if both bots are still active after the 3 min round. Judges will pick the winner based on points. 3 points given for damage, 2 for control and 2 for aggression.

There is a long list but I think this will get most people started. Keep in mind these things when purchasing parts. #1, this is a battlebot and parts WILL be destroyed. Sometimes the cheaper option is the best. #2, you are standing 2 feet away from your bot. A $300 radio and receiver are not needed.

Most of our bodies are 3D printed but you can build it out of anything you wish.

Drive motors – Most of us use N20 motors and 2 brushed motor ESCs to control them. The motors have gears on them and can make all the difference in the world depending on your needs. A 30/1 ratio will give you a fast bot with very little torque. A 70/1 ratio will give you a bot with a lot of torque but will be slow. *** when purchasing your brushed motor ESCs make sure to get the one WITHOUT a break! *** https://smile.amazon.com/gp/product/B071478FMY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1


You can also use micro servos with no need for an ESC but we have seen lots of issues with servos twitching causing bots to just spin, also stripping out gears.

Weapon motors and controller. – Most of us are using racing drone motors and ESCs for our weapons. (they don’t have to be top of the line motors since you are not actually using them to race drones.) Also pay attention to what direction the motor is supposed to spin. All motors can spin both directions but the nut that holds the weapon on needs to spin correctly or the weapon will fly off.



Radios and Receivers – If you already have a 2.4 ghz radio just use that. if you do not, a very entry level controller is the flysky FS-i6. It is a 6 channel radio and will work perfectly for this.


Batteries – This mostly depends on 3 things. The power rating on your motors, your size you can fit in the bot and the weight you have left over to stay under 300g. Most of us use a 2s lipo around 200-300mAh – just pay attention to the connectors to make sure they will fit into your ESCs. Most batteries with a JST connector will work. You can always put a different connector on (just be careful!)