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Robot Event at the Seattle Center

If you are ready to get started, use this guide. While the creative possibilities in robot combat are endless, we'll start with some simple options for everyone, even the absolute beginner.

How to get started in combat robotics

Go to events

Many builders get "hooked" by watching robots on TV or on YouTube. While you can learn from watching matches, it can be difficult to know how to get started from these sources. You might be able to find and connect with local robot builders using Discord or Facebook, but the first thing that every new builder should do is to go to Events and see how things are done in the real world. A typical small event is one day long, with check-in and preliminaries in the morning, and competition until every match has been completed. Some will even have restaurants or food trucks available, but in others you will need to prepare for your own needs.

Even if you don't bring a robot, you should ask the event organizer if it is OK to walk around the pits and talk to the builders. Watching them prepare for their matches and repair robot damage will help you figure out what you'll need for your first event. While builders are generally friendly and helpful, do remember to be courteous, as some of them will be preparing for a battle with very limited time, and often will not be able to talk to you while they work.

Learn the rules

Each robot combat event is governed by rules that specify such things as bot size and weight, allowable weapons, and safe behavior for both you and your bot. Learn what you are allowed to bring, how the event is scored, and how matches are structured. Listen in during the Driver's Meeting before the first match for a summary of requirements for participants.

Before you compete, read the event rules carefully; even if an event adopts SPARC rules or another standard, local changes are not uncommon. Check with the event organizers if you have any doubts about whether your bot will be accepted.

Borrow a robot

If you aren't very familiar or comfortable with building things, and you want to experience robot combat without spending much money, ask about "loaner bots" at your local event. Some enthusiasts have a "stable" of several robots used for small gatherings, lectures and demonstrations. Some even rent their bots out for parties! You might be able to compete for just the cost of the entry fee. These bots will usually be small nondestructive types that are fairly durable.

After a little experience driving a bot, think about owning your own. If it sounds interesting, read on!

Building your own robot

150 gram combat robot

If you have a great idea for a design, and the skills to make it happen, follow that dream! Most people, however, will want to start with a robot that has already been designed. There are two ways to do this. One is to buy a factory-made kit, and the other is to follow an existing design.

Either way, in the process of assembly, you'll learn everything that goes into building your own bot. As you become familiar with the pieces, you'll not only begin to understand how it works, you will also better understand the ways it will fail. When you walk away from a match with a broken bot, you either need to have a plan to fix it, or you will need to call on the help of the other teams.

Pick a weight class

Once you've been to an event and decided to build a robot, you need to pick a weight class for your first build. Take into consideration which weight classes are supported in the event(s) you plan to attend, your budget, and your building skills. Most builders start with "insect-weight" bots (the smallest and lightest classes) because they are the cheapest to build and maintain. Generally things get more expensive as they get bigger; the larger the weight class, the more destructive your opponents' bots will be, and the higher the likelihood that your bot will be damaged and require repair. Also, the building / fabrication requirements are very different for a 1-pound robot vs. a 30-pound robot. Start with something that you think you'll be able to complete, and if you have fun then you might go ahead and build a second and third robot.

Building from a kit

If you've decided to go with a factory-made kit, you'll assemble a robot using instructions. Many will include a simple radio for control; others require you to buy one. Read the Radios section for suggestions. A few simple hand tools are all you will need to get started.

Ask your local event organizer if there are any robot-building classes available. You might be able to join a small group where everyone builds their own bot from a kit of parts.

You should buy replacement parts along with your kit. For example, many kits have exposed wheels, and tires and wheels frequently are damaged by aggressive opponents.

Building following a design

If you're feeling more adventuresome, you can construct a bot according to plans you can get online. In almost every case these plans are free, but it can be tricky to judge which ones are worthwhile. Your local builders will have recommendations for you. See the 3D printer page for a long list of available designs. Access to a 3D printer is required to make some of the parts for nearly every available design.

A beginner's best bet is often to build in the 150 gram weight class, since these bots are small, inexpensive, and easy to repair when damaged. Local events almost always have a 150g competition.

As you compete, you might come up with changes to the design you're using, like better armor or improved weapons. Experiment and learn, and don't be afraid to try wild ideas or to use scrap materials -- just stay within the weight limit and the rules. If you can do 3D design on a computer, you can also modify the plastic components of your kit.

Side note about parts: Robot combat is an unusual hobby that is not well served by most hobby shops. Your local hobby or radio-control supply house probably specializes in trucks and racing, flying and sailing models, or multirotor aircraft. Even if they have a great selection of parts, they won't know what equipment is suitable or allowed by the rules, and they may be reluctant to sell to someone who intends to risk damage of their products. As a result, specialty robot combat suppliers have been created to meet the needs of people engaged in the sport.

Designing your own robot

If you want to go your own way, building robots of your own design is the pinnacle of competition and success. Whether you carefully engineer a plastic chassis for 3D printing, or rummage in the junkyard for bits and bobs, the goals are yours to set.

Building and competing with your robot is supposed to be fun. Know yourself and pick a design that you will enjoy, but be sure to do something within your capabilities. Building a pneumatic flipper with no prior experience isn't a good choice for your first bot. Many in the hobby recommend starting with a simple pusher or lifter design, because more complicated designs require some knowledge of engineering, mechanical design, and materials science.

Picking components

Some people spend a ton of time picking motors and batteries and all the things that go into your first robot. It pays to take some time and make informed choices, but even advanced builders iterate and discover new components to improve their bots. Don't let 'perfect be the enemy of good'. Pick things that work, then iterate and make improvements over time as you go. If you are new to fabricating things take a look at the NameThatPart page to learn about different materials and some of the basic things you'll need to create your robot.

Build and test your robot

Before you start your build you want to make sure you have the right tools. Nothing is more frustrating than setting aside time to build your robot only to find that you are missing a tool needed to build it.

Safety is always important when building and testing your bot. If you have active weapons, begin with the weapons completely disconnected or removed. Do a "wheels-up" test of your drive system to make sure it is working as expected. Ensure that the failsafe is working correctly using just the driving motors first. If everything works, take the bot for a test drive before enabling the weapon, if you can do it safely.

Once the driving motors are tested, you can install and connect the weapon. Weapons tests should be performed using a reinforced test box. Some builders will set up a camera to observe and record the bot while they and others remain safely out of the way. Get into the habit of performing tests in safe environments, as this is frequently a requirement in competitions.

Optimizing your robot

Beginning builders may not be aware of all the ways that the transmitter, receiver, and motor controls can be customized. After you've had some "stick time" driving the bot you may find it isn't as easy to control as you expected. Here are a few tips:

  • If you can't predict where the bot will steer, you may be having radio issues, but often it's poor traction; try a different driving surface.
  • If it steers to one side, you might have one motor faster than another; you can set your radio or ESC to limit the speed on one motor or boost another.
  • If your ESC offers braking, try it; you might find it easier to precisely position your bot before an attack.
  • You might be able to gain an edge when using your weapon. Setting endpoints and/or rate curves for servo motion on a flipper, for example, could position it for faster response to your stick movements.

Getting Started Guides

Preparing yourself

After the bot is built, it must be operated. Combat robots need drivers to succeed. Two keys to success in the bot arena are driving skills and strategy.

Master driving skills

First, you must become a master of your own bot. Find or make a safe place to test your bot without chance of injury to yourself, family, pets, and others, and get plenty of practice driving it as often as possible. Learn how long the battery will hold out before it must be charged. If possible, adjust your controls so that the bot moves and performs as your hands expect it to; for example, adjust the bot or the radio so that when the stick is pushed straight forward, the bot will go straight ahead, and not veer to one side. All of the bot's motions should be predictable and reliable. Then you can practice your moves, just as with any sport, even if all you have is a wood-block dummy to push around.

Study and engage

You will need to effectively engage your rivals in the battle arena, identifying their strengths and seeking out and exploiting weaknesses in their bot designs and in their own driving. You might be able to watch videos of your opponent bots in prior matches to learn about their behavior. However, only in real combat will you learn all the instincts needed to adapt to ever-changing situations. Robot combat is a true sport, and its techniques can be learned and studied not only by watching videos, but by going to events and fighting.

Pit strategy

While at each event, you will have your own spot in the "pits" for repairs and adjustments. Take the time to visit as many competitor's pit tables as possible during the competition, and see what they're up to. It's not uncommon for your opponent's bots to be refitted from one competition to the next, or even modified for individual matches, and you should be prepared with new tactics against potential new threats. Imagine the advantage in knowing your next competitor has a stronger weapon than before, or that they have replaced their armor with fresh plates angled to deflect your bot... or maybe they have taken too much damage, and had to switch to their old, slightly cracked bot frame in order to remain in competition. There is no formal homologation in combat robotics; anything that meets the weight limit and the rules is fair game, and it's best not to be surprised just at the moment your match starts.

Strong spirit

Finally, steel yourself for failure. Parts will fail, things will break, batteries run low, circuits overheat, gears jam, belts fall off, connectors come unplugged, and mighty opponents may cut your bot to ribbons. "The general rule of thumb in any robot competition regardless of weight class is not to put a bot in the arena you aren't comfortable having destroyed."[1] If defeat comes, congratulate your opponent, return to the pits, rebuild, and return to the arena and triumph.