We have been getting a lot of e-mail asking us “How do I build a BattleBot?” well, the answer is not that simple. You must do a lot of research before you begin. We can not tell you what kind of robot to build or how to build it. You have to do the work yourself. There are many websites with info on the basics, but the final design must be your own brainchild.
Read the rules
The first thing you need to do is read and understand the rules to battlebots. Read them over and over until you have a good understanding of what is and isn’t allowed.
Next you must decide what weightclass you want to compete in. I suggest you start with a lightweight or middleweight your first time out. We spent over $3000.00 on our middleweight Psychotron. We expect to spend about $5000.00 on our next heavyweight.
What type of robot do you want to build? There are many kinds of weapons out there, wedges, spinners, saws, hammers, lifters, etc. Each one has it’s own set of design problems and limitations. A wedge is by far the easiest design but be warned, the judges were really biased against wedges in the last competition. This is a televised event so try to make your robot as interesting and innovative as you can. I can speak from experience when I say noise, sparks, and speed will get you more points than just pinning your opponent against the spike strip.
I would stay away from walking robots, gas engines, hydraulics, and pneumatics for your first time around. Stick with electrical power. Electric is the easiest and most reliable of all the power sources out there.
Once you have decided on the basic design you will need to decide what parts you will use to put it all together. There are eight basic parts to an electric powered BattleBot.
1) Radio control
2) Motors
3) Batteries
4) Speed Controller
5) Drivetrain
6) Chassis
7) Armor
8) Weapon
Radio Control
The radio control unit is the brain of the BattleBot. These are the same radios that the R/C airplane and R/C car guys are using. The new rules however state that only PCM type radios with the 75mhz ground frequencies will be allowed after Dec 31st 2001. So if you buy an airplane or helicopter radio you will need to have it converted from 72mhz to 75mhz. There are several manufacturers of radio control units. The most popular are: Futaba, Hitec, Innovation First, and Airtronics.
Radios have a set number of channels. Each channel will allow you to control an individual function on your BattleBot. You will need at least two channels, one for steering and one for forward and reverse. Additional channels may be needed for controlling weapons. I recommend you get a six-channel radio now because you will want those extra channels at some point down the road. A good 6 channel PCM radio will cost around $300.00 Tower hobbies has great prices on radios but you will need to get it converted to 75mhz. Contact D&M electronics for frequency conversion.
Motors
The motors are probably the most important part of the BattleBot. If you skimp on the motors all the rest of the parts won’t mean a thing. Get the beefiest motors you can fit into your weight class. The type of motor you choose will depend on your drive train. If you want to go the easy route I recommend gear drive motors. The drivetrain is already worked out for you. You simply bolt the wheels directly to the motors. National Power Chair has great gear drive motors all ready to go. They also sell wheels ready to bolt onto the motors. These are great motors for middleweights on up to super heavyweight battlebots. Most of the lightweight builders use rechargeable drill motors. The DeWalt motor/gearbox combination seems to be the most popular. I personally would not recommend plastic gearboxes in a BattleBot.
Batteries
The batteries are the blood of the BattleBot. You need to squeeze as much power out of your batteries in a three-minute match as you possibly can. In addition you must be able to recharge or switch batteries quickly. You may only have 20 minutes between fights so you must be able to get back to full power really fast. Most electrical systems run on either 12 or 24 volts. The new rules allow up to 48 volts, that’s 4 12-volt batteries wired in series. Make sure all your electrical components are rated for the voltage and amperage you intend to use. There are two basic types of batteries allowed by the rules, Sealed Lead Acid Batteries and NiCad batteries. The type you chose will depend on both your configuration and budget. SLA batteries are by far cheaper than NiCad battery packs.
Speed Controller
The speed controller is what takes the radio signal and converts it into electrical power to drive the motors in forward or reverse. Speed controllers are very expensive and sensitive components. When you see smoke pouring from a BattleBot during a match is most likely the speed controller making that magic smoke. Smoke bad, smoke not good for bot. Make sure that you purchase a speed controller that is rated for the motors and batteries you will be using in your bot. It is a good idea to use a speed controller that is over rated just in case you stall out the motors. If you do not want to blow up your expensive speed controller we recommend using fuses between the motors and the speed controller and between the battery and the speed controller when operating your BattleBot.
Some good speed controllers are available from Innovation First and Vantec. Be ready to spend between $300.00 – $800.00 for good speed controllers
Drivetrain
The drivetrain on a BattleBot must be bullet proof. If something breaks on your drive train you are history. Most losses in the battlebox are due to drivetrain failure, so build it tough. There are several different types of drivetrains; Chain drive, gear drive, belt drive friction drive and gear drive motors as I mentioned above. All have their advantages and disadvantages. Do a lot of research on this subject before you decide what type of drivetrain you will use in your BattleBot.
Chassis
All of the different parts of a BattleBot have to be assembled together onto a chassis. Much like the frame of a car the chassis is what holds everything together. Some chassis are welded steel, others are machined out of a solid block of material. Biohazard has by far one of the most innovative chassis I have ever seen. It is machined out of several different types of alloys to make it both lightweight and strong.
Remember that whatever type of chassis you build it must be able to take a beating from the pulverizers and the killsaws.
Armor
A BattleBot is much like a tank in that it is covered with some type of armor plating. Your armor must be strong enough to survive the killsaws and other weapons, yet also be light enough that your battle bot will not be over weight. Titanium is by far the lightest strongest material used for BattleBot armor but it is very expensive and hard to work with. 6A1/4V is the most popular grade. Aluminum is softer but it is easy to cut and drill. If you use a softer material like aluminum we recommend making spare panels that you can replace in between matches. Aluminum has one other distinct advantage, it does not spark. If you get stuck on a killsaw or get attacked by a sawbot like Minion, the judges will not see a shower of sparks like titanium or steel armor would make.
Weapon
Your weapon is probably the one thing that will make your robot stand out from the rest. It must inflict maximum damage to your opponent’s robot without self-destructing. Think of ways to cut, smash, lift, throw, split and otherwise maim your opponent. Remember that points are awarded for aggression, strategy, and damage. All three of these categories can be enhanced by the proper choice of weapon. Weapons can be gasoline powered, electric, pneumatic, or hydraulic.
These are just the basics you need to know before you begin designing a battlebot. I have left out a lot of intricate details that you need to find out by researching and reading. I have compiled a helpful list of links to get you started on your research, good luck.
Builders Websites
Team Biohazard Great info on materials
Cool Robots.com By far the best place for info on getting started
Robot Combat.com Great list of frequently asked questions
A Technical Guide To Building Fighting Robots
Team S.L.A.M. Lots of good info
Puppet Master Robotics
Team Hazard Very good tips for robot builders
Online Calculators
Weight Calculator
Conversion Calculator
Calculator City
Batteries
Battle Packs
Battery Mart
Batteries.com
Odyssey Batteries
Power Sonic Batteries
Books & Videos
Robot Books.com
Team Delta
Motors
National Power Chair Robotics
Speed Controllers
Diverse Electronics Not widely used in BattleBots
Innovation First Victor 883 speed contolers as used by Team Rockitz
Vantec 2 Ch high end speed cotrollers used in bomb disposal robots
4QD UK company, Needs interface like Team Delta’s RCE110
