302 Build Your Own Combat Robot has higher priority than an object detector. The more sensors the bot has, the better the information it can process to determine a better reaction. You can also collect a time history of the data in order to predict where the oppo - nent will be, and then planyour attack based on the prediction. For example, if your bot detects that its opponent is off to one side, it can conduct a preplanned attack move, such as moving forward for 6 inches and then making a U-turn maneuver to get behind its opponent, instead of just turning toward the opponent. This generally requires a lot more processing power than a Basic Stamp. There are many microcontrollers available today that have this type of capability, such as the MIT Handyboard that uses the Motorola 68HC11 microcontroller, or the Robominds (www.robominds.com) board that uses the Motorola 68332 microcontroller. Traction Improvements As stated earlier, weight and traction are very important in a sumo bot. Most mini sumos are two-wheeled bots. In the international robot sumo class, there is a wide range of two-, four-, and six-wheeled bots. And most of them have a single motor directly driving each wheel. After the bot’s wheels have been modified to have the highest possible coefficient of friction, and the bot is at its maximum weight, what is left to increase its pushing power? Increase the robot’s apparent weight. The way this is done is to add a vacuum system to the bottom of the bot. The vacuum system then sucks the bot down to the sumo ring, thus increasing the forces on the wheels, and increasing the pushing power of the bot (assuming the motors don’t stall!). The rules of the contest prohibit sticking or sucking down to the sumo ring; but if the robot can continuously move while it’s “stuck,” then the vac- uum system can be used because it doesn’t interfere with motion. The Japanese make the best vacuum-based sumo bots. These bots are so good that they can compete on a sumo ring that is upside down without falling off! One of the drawbacks to the vacuum-based bots is that they can generate so much vacuum that it literally tears the vinyl surface off the sumo rings. Under the rules of the contest, if a bot damages the sumo ring, it is disqualified. Unfortunately, once the ring is dam - aged, no other bot can use the ring. This is why most clubs specifically prohibit the use of vacuum systems. Robot Part Suppliers There are several companies that sell parts to build sumo bots. Lynxmotion (www.lynxmotion.com) sells enough parts to build complete and competitive sumo bots. Figure 13-15 shows a photograph of a six-wheel-drive international class sumo bot built by Jim Frye of Lynxmotion. This bot has a unique feature where the front scoop deploys forward after the match starts, which makes it easier for this bot to get underneath its opponent. This bot also uses a Basic Chapter 13: Robot Sumo 303 Stamp 1 for the microcontroller. Acroname (www.acroname.com) sells a wide variety of parts that can be used to build quality sumo robots. Mondo-tronics (www.robotstore.com) and HVW Technologies (www.hvwtech.com) also have a wide selection of robot parts. Annual Robot Sumo Events The following is a list of some of the largest annual robot sumo contests. This is not a complete list. There are many other contests held each year. This list only shows some of the largest events: ■ All Japan Robot Sumo Tournament: www.fsi.co.jp/sumo-e ■ Seattle Robotics Society Robothon: www.seattlerobotics.org ■ Northwest Robot Sumo Tournament: www.sinerobotics.com/sumo ■ Portland Area Robotics Society: www.portlandrobotics.org ■ Western Canadian Robot Games: www.robotgames.com ■ Central Illinois Robotics Club: www.circ.mtco.com ■ San Francisco Robotics Society of America: www.robots.org At this point, you should have enough information to get started in the exciting world of robotic sumo. As you gain more experience competing in sumo tourna - ments, you’ll learn how to improve the designs of your bots, and help your com - petitors improve their designs, as well. Caution: robot sumo can be addictive! FIGURE 13-15 International class sumo robot named Overkill. (courtesy of Jim Frye) [...]... sport is all about 315 316 Build Your Own Combat Robot P ete Miles—Building Live Wires For a long time, I daydreamed about building the perfect combat robot Since I’d watched robot competitions on TV religiously and had built several winning mini sumo bots, I figured I could easily build a combat machine When I read an invitation from The Learning Channel (TLC) on the Seattle Robotics Society e-mail service... and allow plenty of time to build and test your robot By now, you should have enough information to get started building combat robots It is a fun and exciting world, so what are you waiting for? Start building your robot! 327 chapter 15 Afterword Copyright 2002 by The McGraw-Hill Companies, Inc Click Here for Terms of Use T he Future of Robot Combat The sport of combat robotics has boasted an almost... aluminum (Whatever you do, don’t use 1100 series aluminum in your robots This is one of the softest forms of aluminum you can get I used it because I already had a big sheet of it, and I didn’t want to spend any more money on the robot. ) Figure 14-10 shows the next step of the fabrication process 3 19 320 Build Your Own Combat Robot FIGURE 14 -9 Laying out the components on a plywood board to get a visual... educators and academic roboticists for high school students “We’re builders ourselves,” he explains, “and so we said, ‘wouldn’t it be great to learn about robots in school?’ BattleBots IQ will be an elective that students can take to apply all the math and physics and science they learn in class to build a real robot. ” Greg hopes that BattleBots IQ will be more 331 332 Build Your Own Combat Robot the sum of... tested the robot more before the event, but six weeks really is not a lot of time to build and properly test a robot Live Wires didn’t do well in its first competition, but it was a lot of fun to build and it was truly heartbreaking for us to watch it fail My experience with Live Wires is similar to many combat robot builders When you take a lot of shortcuts and don’t allow enough time to build the robot. .. hand carried the robot outside, set up an empty 55-gallon drum, and put up a few traffic cones for a show When they asked us to show off the robot, we hooked up the batteries and turned on the transmitter At this point, I was biting my lip, expecting to see the same type of failure I saw the night before I pushed the throttle forward, and the robot took 321 322 Build Your Own Combat Robot FIGURE 14-11... Wires coming around the first bend in the course At this point, the robot started having problems One side of the bot stopped working so it started going around in circles This was a rather disconcerting experience After the time expired, we gathered up 325 326 Build Your Own Combat Robot FIGURE 14-16 Live Wires at the weigh-in at Robotica— notice the two front-end attachments the bot and took it apart... important in robotic combat: driving ability and pleasing the crowd Battles have been lost due to poor control of a robot s movement in the arena For this reason, you should test drive your robot as much as possible before competing and discover early how to compensate for odd quirks Pleasing the crowd is also important; if two robots are tied in a match, the vote of the crowd decides who wins A robot with... little sand is added to it, it can cut any material known to man One of the nice things about an abrasive waterjet is that it can cut some rather intricate features without difficulty 317 318 Build Your Own Combat Robot FIGURE 14-7 Flat pattern parts for the cordless drill motor mounts Originally, we wanted to use Vantec motor controllers for the robot When I called Vantec to order one of their RDFR... odd-shaped screw, I used the Bosch screws instead of trying to find my own FIGURE 14-13 Cross-sectional layout of the new motor/sprocket shaft adapter 323 324 Build Your Own Combat Robot Step 8: Adding a Weapon Once the core structure was built and the new motor shaft adapters were fabricated, we had only two days left until we had to ship the robot to the TLC studios, and we still didn’t have a weapon We . 14-1 Chew Toy 308 Build Your Own Combat Robot Research what supplies you already have on hand to do your building. What tools do you own or have access to? Do you have space in which to build or have access. wanted a fast robot, we really didn’t know what fast meant in this context. Since the robot s speed is a function of the motor speed, 316 Build Your Own Combat Robot Chapter 14: Real-Life Robots: Lessons. are decent sized with deep treads for added traction. 310 Build Your Own Combat Robot Chapter 14: Real-Life Robots: Lessons from Veteran Builders 311 The ammo box was destined to receive all the