chapter 1 Welcome to Competition Robots Copyright 2002 by The McGraw-Hill Companies, Inc. Click Here for Terms of Use.E L C O M E to the world of combat robotics. You’ve watched them on TV. You’ve seen models of them on toy store shelves. You’ve seen them featured on the covers of magazines. You might also be among the lucky ones who have actually sat arena-side and watched in person as seemingly sane men and women guided their creations of destruction toward another machine with the express goal of mangling, dismembering, and smashing the opponent. Television has brought this controlled mayhem into the living rooms of America. You cheer wildly as your favorite robot with its spinning hammers rips the steel skin off its foe. Your robot chases its limping target into a corner, only to have a series of saw blades arise from the floor and send your hero sailing across the arena. The TV cameras pan over to the operators of the losing robot; they are smiling. Even in a moment of havoc, both sides are having fun. Parts and sparks are flying, and smoke wafts upward from the hapless opponent as hazards and weapons reach their targets. The crowd cheers and banners are waving. A winner is announced, and then two new bots start at it. You can not stop grinning. “This is cool!” After the program is over, you turn to your friend excitedly and say, “I’mgonna build one of those robots.” “Yeah, right,” she says. “You can’t even program the VCR. Good luck building a robot.” “Hey, I’ve got a book on how to build ’em. I’ll start small, maybe build one of those little sumo robots. It’s a kick to watch those little guys try to shove each other out of a ring. I have some friends who can help me get started. I’mgoing to do it!” Robot combat has come a long way from its origins. The founding father of the sport is Marc Thorpe. He came up with the idea for robotic combat while experimenting with attaching a remote-control tank to his vacuum cleaner to make house cleaning more fun. After a few years spent developing the rules for a game where two robots would duel in front of a live audience, a new sport was created: Robot Wars. The first official combat robot event was held at Fort Mason Center in San Francisco. It was a huge success. Since Robot Wars first came on the scene, thousands of people have participated in building combat robots, and millions have watched and cheered on their favorite bots. Many new combat robot contests—such as BattleBots, Robotica, and BotBash, to name a few—have been spawned from the original Robot Wars competition. 2Chapter 1: Welcome to Competition Robots 3 This sport has become so popular, in fact, that many robots have become better known than their human creators. For example, devout followers of robotic combat are familiar with such famous builders as Carlo Bertocchini, Gage Cauchois, and Jamie Hyneman, but these mens’ robots—Biohazard (pictured in Figure 1-1), Vlad the Impaler, and Blendo, respectively—are now bona fide household names among the millions of people who watch BattleBots on TV. The various robotic combat events have seen many different types of machines, from two-wheel-drive lightweight robots to six-wheel-drive, gasoline-powered superheavyweights. Even walking robots, more commonly known as StompBots, have entered into the mayhem. Probably the most well-known StompBot is the six-legged superheavyweight Mechadon built by Mark Setrakian. Setrakian has even built a super heavyweight snake robot. Though his unusual robots have not won any events, they’ve all been outstanding engineering achievements and great crowd pleasers. The weapons on these robots range from simple wedges and spikes to jabbing spears, hammers, and axes, to spinning maces and claws, hydraulic crushing pincers, and grinding saw blades of every type, size, and color. The destructive power of these weapons has been used for everything from scratching paint off a rival bot to denting aluminum plates, punching holes through titanium and Kevlar, ripping off another robot’s entire armor plating, and completely disintegrating an opponent in a single blow. One of the most destructive robots the sport has seen to date is Blendo. This spinning robot, more commonly known as a SpinBot-class robot, totally destroyed FIGURE 1-1 Biohazard, a superstar of robotic combat. (courtesy of Carlo Bertocchini)many of its opponents in a matter of seconds. It had such destructive force that it was once banned from continuing to compete in a contest and was automatically declared co-champion for that event. Today, most combat robots are remote-controlled; but in the early years of Robot Wars, there were several fully autonomous combat robots. These robots ran completely on their own, using internal microcontrollers and computers for brains, and sensors to find and attack their opponents. Many people think autonomous combat robots would be too slow to compete because they would require too much time to locate and attack an opponent. This isn’t always the case, however. The 1997 Robot Wars Autonomous Class champion, Thumper (built by Bob Gross), won a match in 10 seconds flat. That’s Thumper in Figure 1-2. Today, most autonomous combat robots are found in robot sumo events, where two bots try to find and push each other out of a sumo ring. In this event, bots are not allowed to destroy each other. Sumo builders face a unique challenge, as they design their bots to “see” their opponent and push them out of the ring before getting pushed out themselves. This contest has become increasingly popular in recent years, and new sumo events are popping up all over the world. In the past, competition divisions consisted of man versus man, or team of men versus team of men (let’s face it—it began as a male-dominated sport). Strength, speed, agility, endurance, and strategy were the only factors that determined the winner or loser. Thanks to robot combat, this isn’t the case anymore. At robot competitions, ingenuity, creativity, and intelligence now rule the game. No longer are 6-foot 5-inch, 240-pound male “athletes” dominating the game. A 10-year-old girl with excellent engineering skills can now defeat a 250-pound former 4 Build Your Own Combat Robot FIGURE 1-2 Thumper, an autonomous robot built by Bob Gross, won big-time at Robot Wars in 1997. (courtesy of Bob Gross)Chapter 1: Welcome to Competition Robots 5 NFL linebacker, and a wheelchair-bound person can run circles around an Olympic gold medalist. Robot combat has leveled the playing field so that anyone can compete against anyone on equal ground. What Is a Robot? Now that you’ve made up your mind to build a robot, you’re probably sitting back wondering just what you’ve gotten yourself into. “What is a robot?” you ask yourself. Surprisingly, there are many definitions, depending on whom you ask. The Robot Institute of America, an industrial robotics group, gives the following definition: “A robot is a reprogrammable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks.” These people, of course, are thinking only of robots that perform manufacturing tasks. Now that you’re thoroughly confused, Webster’s New World Dictionary defines robot as “any anthropomorphic mechanical being built to do routine manual work for human beings, or any mechanical device operated automatically, especially by remote control, to perform in a seemingly human way.” Hmmm. Now we seem to be talking about human-formed robots, like in the movies, or it could be the description of a washing machine, or maybe the Space Shuttle’s “robot arm.” Where did the term “robot” come from? Back in the 1920s, a Czech playwright by the name of Karel Capek wrote a short play entitled R.U.R., which stands for Rossum’s Universal Robots. The word robot came from the Czech word robota, which means indentured servant or slave. In Capek’s play, the robots turned on their masters, which became a theme in many movies and stories in later years—robots doing bad things to people. Only in more recent movies have robots become friends of humans and started doing bad things to other robots. To this day, those in the field of robotics still argue about what exactly constitutes a robot. Many people think that if a machine doesn’t have some sort of intelligence (that is, a microcontroller inside), it isn’t a robot. Some might look down their noses and claim that only a multiarmed machine driven by a Pentium 4 processor with 512 megs of RAM and fed by 100 sensors is really a robot. Those at NASA might feel the same way about the Space Station’s Canada Arm. All this arguing really doesn’t matter, because everyone has their own definition of what a robot is—and everybody is right. Whatever you choose to call a robot is a robot. Combat Robot Competitions Before we start talking about types of robot competitions, let’s cover a brief history of the events that gave rise to this sport. Organized robot competitions have beenaround since the late 1980s, and have been rapidly growing ever since. The following is a short history of some of the most popular robot contests around today. There are many other competitions aside from those listed here, and new ones are turning up each year. Late 1980s The remote control and autonomous robot sumo contest is invented by Hiroshi Nozawa of Fujisoft ABC, Inc., in Japan. 1989 Inventor and entrepreneur Dean Kamen founds FIRST. This nonprofit organization, “For Inspiration and Recognition of Science and Technology,” pairs up school-age children with local engineers to build robotic projects. 1992 Marc Thorpe discovers that his experiments with building a radio-controlled vacuum cleaner to help with the housework can be turned into a new sport called Robot Wars. 1992 FIRST Robotics hosts its first competition with 28 high-school teams. 1994 Marc Thorpe creates Robot Wars. This is the first major competition where robots face off against each other in an arena in front of a live audience. The first event is held at Fort Mason Center in San Francisco. 1997 Mentorn Broadcasting produces a six-episode series of Robot Wars for BBC television in the U.K. 1997 BotBash, a similar event to the original Robot Wars, holds its first event in Phoenix, Arizona. March 10, 1999 BattleBots is founded by Trey Roski and Greg Munson in San Francisco. August 14, 1999 BattleBots hosts its first event in Long Beach, California, with 70 robots competing. January 29, 2000 BattleBots appears on pay-per-view television, and airs the second BattleBots event from November 1999. August 23, 2000 BattleBots begins airing as a television series on Comedy Central. The show quickly shoots up in ratings and finishes its first season as one of the most popular shows on cable TV. April 2, 2001 BattleBots registers over 650 robots at its Spring 2001 competition. April 4, 2001 Robotica begins airing as a television series on the Learning Channel. Early indications show the program is a hit among viewers. August 20, 2001 The new Robot Wars Extreme Warriors, a spin-off from Robot Wars, premieres as a new television series on TNN. 6 Build Your Own Combat RobotAs you can see, the history of robot combat is relatively short in comparison with baseball or football, but all sports have to start somewhere. With its current growth rate, it won’t be long before this becomes one of the most popular sports in the world. As with any game, there are different rules and goals for each event. Following are brief descriptions of some of these contests. The exact details of the events should be obtained directly from the event organizers. BattleBots BattleBots is probably the most popular robotics event in the United States. A large fan base has been accumulating ever since these competitions started airing on cable TV. BattleBots is a single elimination fight-to-the-death contest where one robot tries to destroy another in a 3-minute time frame. If one of the robots becomes incapacitated for 30 continuous seconds, or is destroyed, that robot loses the match. If both robots are still fighting at the end of the 3-minute time frame, the winning robot is declared by how many points they scored. There are three official judges who award up to 5 points each for aggressiveness, damage, and strategy, for a total of 45 points. The robot with the most points wins the match. If your robot is fortunate enough to survive the match, it has only 20 minutes to undergo any repairs before the next match. If the robot faces another fight soon afterward and cannot be repaired in the 20-minute time frame, it must forfeit the next match. The main BattleBots arena is called the BattleBox. Weighing in at 35 tons, this “box” consists of a steel floor measuring 48-feet-by-48-feet, and walls that tower 24ft high. The walls of the BattleBox are made out of Lexan (a highly resilient polycarbonate) ranging in thickness from one inch at the base of the walls to 3/16 inches at the top. There are two 8-foot-by-8-foot entry doors where the robots enter. Within the BattleBox there are a set of hazards and weapons, which are as follows: Kill Saws These are 20-inch-diameter carbide-tipped SystiMatic saw blades that can cut through virtually any material. They can spring up with many pounds of force, easily tossing 340-pound superheavyweight robots into the air. Pulverizers These monster aluminum hammers are used to smash any unfortunate robot that gets under them. Hell Raisers BattleBots competitions occasionally employ these 3-footby-4foot plates that move up 6 inches, wreaking havoc in a robot’s motion. Ram Rods The ram rods are a set of six carbide-tipped spears that shoot up 6 inches from the BattleBox floor with over 60 pounds of force. Chapter 1: Welcome to Competition Robots 7Spike Strip Around the perimeter of the BattleBox is a strip of 180 metal spikes—each one 1-inch in diameter and 3 inches long—that point toward the center of the BattleBox. The Vortex This is a 3-foot-diameter disk that will spin the robot around if it rolls on top of the vortex. The Augers These huge rotating screws mangle any robot unlucky enough to get caught in their grip. There are four different weight classes for wheeled BattleBots, as shown in Table 1-1. 8 Build Your Own Combat Robot FIGURE 1-3 Two-wheel-drive, spike-wielding Toe Crusher, built by Christian Carlberg. (courtesy of Christian Carlberg) More Than Maximum Lightweight 25 pounds 60 pounds Middleweight 60 pounds 120 pounds Heavyweight 120 pounds 220 pounds Super heavyweight 220 pounds 340 pounds TABLE 1-1 BattleBot Weight Classes Walking robots get an extra 20-percent weight increase bonus, so the weight classes for walking bots are 72 pounds for lightweights, 144 pounds for middleweights, 264 pounds for heavyweights, and 408 pounds for superheavyweights. All of the details about BattleBots, including rules and regulations, can be found online at www.battlebots.com. Robot Wars Robot Wars is where it all began—two robots fighting to the death. In the early days of Robot Wars, there was an arena filled with hazards, including spikes, buzz saws, and a swinging bowling ball. Robots fighting in this competition had to avoid the hazards while attacking opponents. Not only were there remote-control robots fighting, there were also autonomous machines competing. Since Robot Wars moved to the United Kingdom in 1997, the event has changed quite a bit. Before the bots get a chance to go to the big fight, they now have to pass a series of obstacle course tests. These obstacles include crashing through brick walls, climbing over teeter-totters, passing between two closing walls with spikes, avoiding large pendulums, knocking over large metal drums, and steering clear of fiery pits. Chapter 1: Welcome to Competition Robots 9 FIGURE 1-4 The vicious-looking Razer has been a crowd favorite for several years running at the U.K. Robot Wars. (courtesy of Vincent Blood)To make the events a little more challenging, the contestant bots have to contend with “house” bots whose main purpose is to destroy anything fool enough to come near them. The smallest house robot is Shunt. At 231 pounds., this powerhouse can pull a Land Rover and wield a deadly axe. Dead Metal, weighing in at 247 pounds., is very effective at using its buzz saw and deadly pincers. The 256 pound titaniumarmored Matilda wields a chain saw on her rear, and the 264 pound Sergeant Bash with his deadly flamethrower can cook his victim when it gets caught in his front pincers. Finally, there is Sir Killalot, at a massive 617 pounds. His pincer claws can cut through the toughest armor and then lift a 220-pound hapless victim—to be dropped into the fiery pit. The lucky winners of the obstacle courses get to move on to bigger and better fights. Below is a list of three of the most popular events that bots must pass in more advanced Robot Wars competitions, prior to moving on to the final round: Pinball In the pinball tournament, bots must navigate around a course and hit certain objects, each of which is worth a different number of points. The bot with the most points wins the tournament. Bots score 5 points for hitting barrels, 10 points for the multiball, and 5 points for each multiball in the pit. Crossing over the ramp is worth 20 points, going through the car door gate is worth 25 points, and moving the sphere out of the pit is worth 25 points. Hitting Matilda’s and Sergeant Bash’s guarded targets are worth 50 points each, and getting past Dead Metal to its target is worth 75 points. All of this must be accomplished in 5 minutes. Sumo The Sumo event is held on an elevated ring, and the contestant bot goes up against a house bot. This is a timed event to see how long a bot can stay in the ring before being pushed off by the house bot. Most of the time, the house robot wins this event, but once in a while a challenger will be successful in pushing a house bot to its doom. The bot with the longest time on the sumo ring wins that event. Soccer Robot Soccer is an event where two bots try to push a white ball into the other bot’s goal.Ahouse bot is positioned in the arena to assist in the game. “Assist” is a relative term because the house bots have a tendency to capture the ball, thus leaving the other two bots to fight. Once the time limit expires, a judge determines which robot is the winner. Robot Wars has several other events that are less common, one of which is the Grudge Match. In this competition, if your bot has a grudge against another bot—including a house bot—it gets the opportunity to fight that bot one on one. 10 Build Your Own Combat RobotAnother event is the Tag Team match, where two bots team up against two other bots. A popular event is the Tug-Of-War, where a contestant bot is attached to a house bot via a rope. Between the two bots is a pit. As you guessed, the contestant bot must pull the other bot into the pit. Yet another popular event is the Melee. Here, three or more robots fight against each other and the last one standing wins the melee. (BattleBots has a similar event to the Melee, which is called the Robot Rumble.) Table 1-2 lists the weight classes for Robot Wars. The official Robot Wars Web site is at www.robotwars.co.uk. BotBash BotBash is a smaller-scale version of BattleBots. The rules of the contest are very similar to BattleBots, with the big difference being that BotBash is a double elimination tournament. This means your bot can lose one round and still be able to fight on. This is a nice change for bot builders because if a battery connector falls off, or some other unforeseen problem arises in a match that causes you to lose, you can still prove that your bot is the best by winning the remaining rounds. Another big difference is that the BotBash bots have lower weight limits. Tables 1-3 and 1-4 list the BotBash weight classes for the wheeled and walking robot classes. As with BattleBots, there is a 3-minute time limit; and if both bots are still fighting, a winner is declared by points. Here, the three judges award one point each for aggression, strategy, and damage, for a total of nine points. Each year, the BotBash tournament offers different events aside from one-on-one battle. In the past, they’ve featured a Capture the Flag event where two cones (flags) are placed at opposite sides of the arena and the bots race to capture the opposing bot’s flag. The bots can plan either an offensive or defensive role to attack or protect the flag. The bot that touches the other bot’s flag first wins the match. Other events at BotBash include obstacle courses and sumo events. Occasionally, BotBash tournaments feature autonomous events. Because the rules and events for each tournament change each year, builders must keep up-to-date on the rules and regulations. The official BotBash Web site is at www.botbash.com. Chapter 1: Welcome to Competition Robots 11 More Than Maximum Featherweight 0 pounds 25 pounds Lightweight 25 pounds 50 pounds Middleweight 50 pounds 100 pounds Heavyweight 100 pounds 175 pounds TABLE 1-2 Robot Wars Weight Classes 12 Build Your Own Combat Robot FIGURE 1-5 Spike III, a third-generation robot built by Andrew Lindsey, a long-time combat robot competitor. (courtesy of Andrew Lindsey) More Than Maximum Class A 0 pounds 12.9 pounds Class B 13 pounds 30.9 pounds Class C 31 pounds 58.9 pounds Class D 59 pounds 115.9 pounds TABLE 1-3 BotBash Wheeled Robot Weight Classes More Than Maximum Class A 0 pounds 24.9 pounds Class B 25 pounds 55.9 pounds Class C 56 pounds 87.9 pounds Class D 88 pounds 172.9 pounds TABLE 1-4 BotBash Walking Robot Weight Classes Chapter 1: Welcome to Competition Robots 13 Robotica Robotica is a new type of robot combat where bots must complete several courses before they can fight each other. This type of contest has different design requirements; brute strength doesn’t guarantee that the bot will win the contest. Bots need to be more agile and creative to solve each challenge. In this contest, you must keep up-to-date on the rules because the challenges change dramatically each year. There is only one weight class for the Robotica robots. The maximum weight is 210 pounds., and the robot must fit inside a 4-foot-by-4-foot-by-4-foot cube at the start of the match. To give you an idea of the different types of events Robotica contestants face, the following are details on qualifying obstacle courses from the first two television seasons. Season One In the first season of Robotica, bots had to survive three different preliminary rounds. The first event was the Speed Demons race, where two bots raced around a figure-8–shaped track in opposite directions. The first bot that finished eight laps won the race. If the 2-minute time limit expired with both bots on the track, the race was ended. Points were given to each bot for each lap finished. The bots were allowed to crash into each other when their paths crossed. The second event was the Maze event. Here, the bots had to navigate to the center of a maze and overcome several obstacles, which included a teeter-totter ramp, a weighted box, spiked paddles, speed bumps, a guillotine, and a waterfall. The first robot to the center won the event. Points were given to each bot for each obstacle successfully navigated. The final event was the Gauntlet event. Each bot had to crash through five increasingly difficult obstructions. The obstacles included a pane of glass, a wall made of pint-sized metal cans, small bricks, stacked cement blocks, and a large weighted box. Two bots ran identical parallel courses, and the first bot that moved the weighted box won the event. Points were also awarded for each obstacle the bot went through. The bot with the most points after the three events won the preliminary round and got to fight the winner of another set of events. The final match, called Fight to the Finish, took place on a 16-foot diameter ring 8 feet off the ground. To win this event, your bot had to push the opponent off the ring to its death on spikes below the ring.Season Two During the second season, the preliminary events changed from three events to two events. The first event was the Gauntlet. In this new version of the Gauntlet, the bots had to run through a diamond-shaped track. Both bots started at the same point but went in opposite directions. They had to crash through a number of obstacles on the first two legs of the diamond track, including a wall of wood, weighted cans, a wall of bricks, and then a cement wall. After all this destruction, the bot then had to crash through the debris field created by the other bot. Once the bot completed the diamond track, it then climbed a ramp to destroy a series of glass columns. When all the glass columns were destroyed, the bots had to climb a final ramp to the victory zone. Bots got points for each obstacle successfully navigated. The bot with the most points won the event. The second event was the Labyrinth. The bots had to navigate through a series of challenges, after each of which was a glass wall to be broken through by the bot. The challenges included a 20-pound box, a suspension bridge, spikes shooting up from the floor, a flip ramp, a sand pit, and a set of steel cargo rollers. When all challenges were successfully navigated and all six glass walls were broken, a seventh glass wall was revealed. The first bot to break the final glass wall received bonus points. To make things more difficult, a set of Robotica “rats” with buzz saws are constantly attacking the bots to impede their progress. Points are awarded for each obstacle successfully navigated, and the bot with the most points wins that event. The bot with the most points after the two preliminary events moves onto the Fight to the Finish event. As with the first season, the bots try to push each other off the ring. The first one falling out of the ring loses the overall match. As you can see by the different events, Robotica is more challenging than a purely destroy-your-opponent type of robot combat. But in order to win Robotica, it still comes down to having the strongest and most powerful bot. The official Robotica Web site is at www.robotica.com. FIRST (For Inspiration and Recognition of Science and Technology) FIRST does not condone competitions where two bots try to destroy each other. However, we are including FIRST in this list because their competitions are very intense and aggressive, and are becoming extremely popular among robot enthusiasts. The FIRST Robotics Competition is an annual design competition that brings professionals and high-school students together in teams to solve an engineering design problem. One of the goals of competition is show students that science, engineering, and inventions are fun and exciting, so they will be inspired to pursue careers in engineering, technology and science. A big part of the event is having students work directly with corporations, businesses, colleges, and professionals to help support them in building bots for the competition. This is a fast-paced competition that starts shortly after the beginning of a new year. Each team has 14 Build Your Own Combat Robotonly six weeks to design and build their bot. After that time, they compete in regional contests and later move on to the final championship. In 1992, the inaugural year of the FIRST competition, there was only one contest with 23 teams entered. Since then, the contest has grown significantly. In 2001, there were 14 competitions with a total of 535 teams entered. FIRST has grown to include Canadian and Brazilian teams, as well. Each year the goal of the contest changes, and nobody knows this goal until the first day of the six-week countdown. During this six-week time period, teams must figure out the rules and goals of the contest and design and build their bot. During the actual contest, a team is paired up with another team, and those two groups of people must work together to solve the prescribed challenge against two other teams. The particular contests are designed so that teamwork is required in order to score enough points. During most of the preliminary rounds, the contest officials decide team pairings. In the finals, a team is allowed to choose its partners. The FIRST organizers believe this helps promote teamwork and cooperation. FIRST robotics is an extremely challenging and exciting contest. Many of today’s famous combat robot warriors cut their teeth in competition robotics by competing in FIRST, either by participating as a member of a high-school team or serving as a mentor to a FIRST team.Alot of the technologies and skills needed for building combat robots are used in designing FIRST robots. The official FIRST Web site is www.usfirst.org. Chapter 1: Welcome to Competition Robots 15 FIGURE 1-6 Team Titan Robotics from the International School in Bellevue, Washington, built Prometheus for a FIRST competition. (courtesy of Larry Barello)Robot Soccer Probably the most difficult robot sport is Robot Soccer. This is an autonomous game where a team of bots works together to score goals against another team of bots. The rules of the game are similar to those in actual soccer games. Bots use advanced vision systems to track the soccer ball, monitor the location of the opposing team’s bots, and know where their own teammates are. All of the bots play their positions just as human players do. There is a lot of cross-communication between all of the bots playing. This contest is usually performed by university students developing algorithms for artificial intelligence. We reference this contest because a lot of the technologies being developed for Robot Soccer players may soon migrate down to combat robots. At some point in the future, there may even be autonomous soccer teams in popular competitions like BattleBot. More information on Robot Soccer can be found at www.robocup.org. Before you start building a bot for a particular contest, you should get a copy of that contest’s current rules and regulations. You can usually find this information on the organization’s official Web site. Keep in mind that some of these competitions have long and complex regulations for builders to follow, and the rules do change from time to time because the contests are evolving into a mature sport. You need to be very familiar with the robot specifications and safety requirements for the contest you have in mind, as they’ll have a significant effect on your bot’s design. 16 Build Your Own Combat Robot The sport of robotic combat has been called “American Gladiators for people with brains” and the “sport of the future.” However, back when I first signed on board with my armored harbinger of destruction, it was just a small bunch of guys getting together in San Francisco’s Fort Mason Center for what could only be described as Rockem’ Sockem’ Robots for grownups. The crowd was small but enthusiastic. The hazards in the arena were walls that pushed in and out, some spinning blades that popped up whenever the guy running them was alert enough to press the lever, and a large metal ball looming from on high that swung like a giant pendulum of death from a chain on the ceiling. Lexan walls separated the audience from the inevitable flying shrapnel and sparks. The floor of the arena was so dented, dinged, and pitted by the last day that you were sorry your robot wasn’t equipped with off-road capabilities. Someone was nice enough to set up a primitive closed-circuit TV so that we in the backstage “pit” area could see what was happening in the arena and know when we should get on-deck for our matches. While we toiled away on our bots, our spot in the pit was so close to the action that we could almost watch the battles if we stood on our chairs. The sound of saws grinding metal and the smell of overcooked batteries, fried wires, and oil filled the air. It was heaven. It was also my robot Spike’s first time competing as a lightweight. We came in third, but where we wound up didn’t matter. Just being a part of the action was thrilling enough. If you needed a screwdriver or blew a gasket, someone was there with a spare to help you get your bot back into the fray. When our Tekin speed control turned into a smoking slagpile, we got a loaner from the guy we were going to be up against in the next match. In the pit, we were all on the same team, working toward a common goal. However, once our bot was in the arena, all bets were off, and it was mano a mano: let the best-made machine win. First PersonThe Scope of This Book Building a bot is not that difficult—if you’ve done your homework on the basic elements involved. It may take you a while to figure out how to do new things, and it might take a long time before you build your dream machine, but consider your first project a learning process—patience and persistence are key when you’re building a bot. Robotics is one of those fields where you need to be able to wear a lot of different hats. That means you must know a little bit about a lot of things, including motors, electronics, wiring, computers, radio transmitters and receivers, batteries, gears, belts, bearings, chains, sprockets, metals, plastics, drilling, cutting, threading, bending, and welding—just to name a few. You don’t have to be an expert in all of these categories—you just need to understand the basics behind each one. Most combat robots are built by a team of people. Each team member is knowledgeable about certain areas of robot building. When you get a group of people together who all know different pieces of the process, it reduces the burden on each individual for having to be an expert on everything. After you have built a couple of bots and competed in a few contests, you’ll become something of an expert in all of the different categories because you will have been involved to some degree with every part of building the bot. Probably the number-one question that gets asked of a bot warrior is, “Howdo I build a robot?” Well, nobody can give you a quick answer. It usually takes months to years to learn how to build a bot. There is just too much stuff you need to know. Most of the time, people learn just by doing it. We all make mistakes, and we learn from them. The scope of this book is to help you, the new robot builder, get started in the exciting field of constructing combat robots. After reading this book, you will have an understanding of all the elements that go into building a bot. Usually, the new robot builder is surprised to find out that there are so many different things that go into this process. This is because most people only see the finished product—the beautiful, gleaming El Diablo or Nightmare or Deadblow—they don’t see the blood, sweat, and tears that went into building it. Chapter 1: Welcome to Competition Robots 17 The hardest part for us was just getting there. We had no sponsors and had to pay our own way for everything. It was tough, and it took months to pay off that credit card, but I would do it all again in the blink of an eye! We met some of the most incredible (and nicest) people. The designs we saw and the creativity of the engineers and imagineers behind their bots inspired us. The generosity in the sharing of ideas, tools, and even parts amazed us. We became part of this amazing community of robot builders and battlers and the camaraderie warmed us. It was one of the best weeks of my life. —Ronni Katz First Person continued