Choose Drive Servos It’s usually recommended using servos instead of motors for an beginner’s antweight because with servos, you do not need a speed controller which saves money and precious weight on your robot. You should look for “micro” servos because they will save you a lot of weight. Be sure to make sure the servo is 360 modifiable. It’s recommended getting high torque servos for combat robots instead of high speed so it’s easy to push other robots around, even if you have a separate weapon. If you cannot find a servo that suits your needs perfectly, consider checking out another section on that site that sells “Futaba” servos. Futaba is a different brand that makes servos. Sometimes they have different sizes than the HiTech brand. Choose a Weapon motor If you have an active weapon (i. e. aren’t creating a “pusher”), then you probably need a motor to move the weapon. If you have a weapon that needs to move really fast (i. e. a spinning weapon), then you should get a geared DC motor (Brushless generally works better, but brushed would work) with a speed controller. It’s not recommended using a spinning weapon for your first antweight because they can be difficult to build and balance properly. However, if you are creating a flipper weapon, then you want to use a servo. It’s recommended to get a micro servo with extremely high torque so it can flip other robots with ease. Another thing to consider when looking for a weapon servo is the type of gears. If you use nylon gears and the motor gets a lot of stress, the gears can strip out over time. Try getting stronger gears made out of metal. Choose Wheels When choosing wheels, be sure to remember the rule that says the robot has to be able to fit within a 4"X4"X4" cube. This means you have to have wheels that have a diameter less than this. It’s recommended to use 2" diameter wheel. Be sure that the wheels can easily attach to the servos securely. Another great technique to use in combat robots of any size is the ability to drive upside down. Yes, the controls will be a bit backwards, but it can prevent you from losing the competition from being immobile. So consider making your robot shorter than your wheels so that it can drive upside down. Choose a Transmitter/Receiver When purchasing a receiver make sure that it has what is called “Fail-Safe operation”. It is a rule to have this in most competitions and a safety feature. The AR500 Receiver does not have this. You will need to purchase a BR6000 Bot Receiver, or another receiver that has this feature. For a transmitter it’s recommended using the Spektrum DX5e. If you built the Remote Controlled Robot found in the related wikiHows, you can reuse that transmitter, but you must buy a new receiver. Choose a Battery It’s highly recommended getting a LiPo battery instead of a NiMH battery. LiPo batteries are lighter. However, they are more dangerous, expensive, and require a special charger. Invest the money into a LiPo battery and a charger to save on the precious weight. Choose a Material The material the chassis and armor is made out of on a combat robot is extremely important because it is what prevents enemy weapons from piercing your electric components. There are three main choices that you should choose from: (Note: There are more, but these are the best for this particular weight class) Aluminum, Titanium, and Polycarbonate. Aluminum is light weight and strong, but it can be expensive and hard to cut. Plus it can not be more than 1mm at all. Titanium is light weight and extremely strong, but is hard to cut and extremely expensive. This also is subject to the 1 mm thickness rule. Polycarbonate, or lexan, is a lightweight, inexpensive, easy to cut, shatterproof, strong plastic that is sometimes used in bullet proofing. Polycarbonate is also a plastic so it can be as thick as you want, but it’s recommended to get it about 1 mm thick. It’s highly recommended using polycarbonate. It’s so durable that this plastic is the plastic that makes up the arena walls for antweight competitions. When you purchase it be sure to get extra, in case you mess up.
Add up the weight of the parts (in grams) and be sure they total less than 150 grams. If you don’t have CAD, download the free version of Sketchup. Take some of the free tutorials on Sketchup to learn all the basics. Create all the components you are using on Sketchup using the size specs you wrote down. Design out your chassis and armor. Be sure to make it less than 4X4X4 inches. Fit all the components into the 3D chassis/armor model to see if they fit at the same time. This will also help you decide where the components will be.
