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As long as there have been twopeople gathered together who havedifferent ideas and skill sets, therehave been competitions of some sort.The recent Summer Olympics was anextreme example of the world’s finestwho gathered together in China toprove who the best athlete in manycategories was. Old records fell as younger or more experienced athletes swam or ran faster than everbefore, jumped higher or further, or performed some series of athleticmotions with more finesse than theothers. An American swimmer walkedaway with a record eight gold medals.

We humans love to present ourfinest to the world in hopes that ourcountry’s competitors are better thananyone else. Robotics is no differentas we are all proud of our coolest,fastest, meanest, smartest, or mostdestructive robot of all and want toshow it to the world in some sort of competition.

In this year’s April issue of SERVO,I touched upon some of the morepopular contests such as the SeattleRobotics Society’s Robothon, thePortland Robotics PDXBot robot competition (both of which have beenpostponed due to the need of leadership), the Robotics Society ofSouthern California’s annual robotfairs, and a few of the nationalevents. As I was more concerned withthe exhibits by different groups, I really did not cover the complexities of these events and the many moreheld around the world.

I also had a few responses from

readers mentioning that I did notcover their event or other events thatwere particularly noteworthy. I spokewith a few personally, and related thatI can never cover the wide spectrumof any topic in modern robotics technology and I just try to cover afew unique aspects of a particular article’s subject. This certainly appliesto the many robot exhibitions andcompetitions as there are so manytypes of contests and competitionsthese days. In this article, I again will highlight a few of the more wellknown robotics contests in a bit moredetail, but, this in no way representsthe very best competitions. They justhappen to be a few of the contests Iknow a bit more about.

Competition can be as simple asone neighbor watching another builda robot. That neighbor then decidesthat he can build an even better one,and so on. It can also arise in a schoolor university where two or more students build a robot that can “oneup” another group of student’smachine. Sometimes a competitiveurge develops when a person watchesa contest on TV or reads about one.

Some of the best competitionsarise when sponsors decide to developa contest with a specific set of rulesand award prizes to the best in thecontest. These can be a simple sciencefair at a local high school, a nation-wide series of contests such as FIRST,or even a government sponsored contest such as the DARPA off-roadGrand Challenge or Urban Challengewith a first prize of $2 million.

Contestants benefit as do thesponsors who can use the winningtechnology to further enhance militaryor other government projects at a far cheaper cost than handing outresearch grants. I’m going to outline a few of the more widely-spread typesof contests and, as I mentionedbefore, these are just a drop in thebucket of the many very interestingcompetitions around the world involving experimental, amateur, anddownright unique robots.

The Seattle Robotics SocietyRobo-Magellan Contest

The varieties of entrants in robotics contests can vary from simplekit-built wheeled robots exhibited byelementary level kids in a local eventto the million dollar autonomous carsand SUVs entered into the GrandChallenge series held in multi-miledesert and suburban environments.

I had the honor of being one ofthe judges for the Seattle RoboticsSociety’s Robo-Magellan contest for several years, held at the SRSRobothon at Seattle Center. This contest was envisioned as an affordable alternative to these government sponsored contests andhas spread to many robotics groupsacross the country. Entries are nothingshort of amazing.

The robots that I’ve seen over theyears range from a few pounds tomaybe 30 or more, and sizes rangefrom a small, remote-controlled carchassis to 18 inches long and 14

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ROBOT COMPETITIONS AND CONTESTS

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inches high, or so. They must weighless than 50 pounds and fit within afour foot cube for the duration of therace. Some crawl away from the starting point at a speed slower thana stroll in the park and others raceaway at breakneck speeds. I’ve seencontestants running behind theirspeeding Robo-Magellan robot, barely able to keep up, with the safety tether in their hand ready foran emergency stop.

Figure 1 (courtesy of SRS) showsa contestant holding the safety tetherin the October 2006 competition.Wireless safety switches are admissi-ble, but most contestants use a wiredtether. In the early years, we had a bitof trouble with the GPS satellitesbeing shadowed from the robots by ahigh wall or even the Space Needle,but this made the contest a bit morechallenging when the competitorstransferred navigation to odometryand compass navigation.

Newer and more sensitivereceivers solved a lot of the GPSreception problems in later years. Inever saw an entry that wasn’t firstclass, though some did manage to get lost or stuck behind obstacles.

As stated in the rules set up bythe SRS, “Robo-Magellan is a roboticscompetition emphasizing autonomousnavigation and obstacle avoidanceover varied, outdoor terrain. Robotshave three opportunities to navigatefrom a starting point to an endingpoint and are scored on the timerequired to complete the course with

opportunities to lower the score basedon contacting intermediate points.”

The ‘chicken switch’ tether I mentioned previously is allowed to disable the robot when it is deemedunable to continue or will run into aperson or obstacle, but all control isautonomous and navigation is by GPScoordinates (no differential GPS toenhance the accuracy), visual cameras(to avoid obstacles and locate the 18”orange traffic cones), and on-boardcompasses.

The contest is held outdoors (forbest GPS reception) and is usually onsidewalks, grass, and has some uniqueramps and turns. The contests at theSeattle Center have always attracted a crowd of people who excitedly follow the robots around the course.Sometimes a person with an orangejacket or hat will confuse the robot so that it deviates from the coursebecause it thinks it has seen theorange cone.

It’s always fun to explain to thecrowd just how intelligent the robotsare and why they do certain things onthe course, (which can be longer than1,000 feet). Scoring is based on time,but points are also given for locatingand touching all waypoint cones, soslower robots have frequently bestedthe speedier machines. Contestantsare given the course coordinates justbefore the contest and are allowed totraverse the course themselves beforetheir robot makes its run (a maximumof 15 minutes is allowed for eachrun). Other groups have used desertcourses, woods, and strictly urbancourses with only concrete andasphalt. To make the course moreinteresting, overhead trees, inclines,curbs, garbage cans, park benches,shrubs, and even streams have beenincluded. Target cones are hiddenfrom view at the starting points andat the waypoints. Go to www.robothon.org/robothon/robo-magellanfor more detailed rules and information.

IEEE MicromouseCompetitions

Running a maze with a robot hasalways been a draw and people have

built robots to solve simple mazessince before the microcomputer age.In 1977, IEEE Spectrum magazineannounced a ‘micromouse’ contestthat would be held in New York in1979. That gave time for the 6,000initial entrants to design, build, andfine-tune their creations. Fifteen finalists were selected for the competition to be run in a 10’ by 10’maze. The winner of this first contestwas a simple, high-speed wall-followerthat used no sort of ‘intelligence’ toseek its goal. These types of mice simply turn a certain direction whendetectors locate the absence of a walland continue turning in that samedirection for the same reason, many times until they eventually (accidentally!) reach the goal. Ruleswere changed to eliminate these types of entries.

As the contest series gained popularity in the early 80s and groupsaround the world became interestedin participating, the rules becamemore defined. ‘Mice’ appeared in allsorts of forms. David Buckley of theUK came up with Quester in 1981 — a large 8” by 7-1/2” by 5-1/2’ micromouse that used a vision systemto detect the maze walls and bumpsensors when those sensors failed.(See Figure 2).

Buckley gained a bit of famewhen Quester was featured in one of the earliest non-industrial robotmagazines, Robotics Age. The FirstWorld Micromouse Competition washeld in Tsukuba, Japan in 1985 andthe top six winners were all locals.After a few sporadic contests in theUS with low attendance and few

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FIGURE 1. Robo-Magellan contestant.

FIGURE 2. Quester from the UK.

entrants, the contest became quitepopular and is now often held in conjunction with electronic businessconferences, especially where IEEE attends.

What is a Micromouse?

A mouse must be self-containedand totally autonomous, no largerthan 25 cm by 25 cm (about 10” x10”) and there is no limit on theheight. It cannot, however, move overor damage the maze walls. The mazeitself consists of a square pattern of16 by 16 squares (18 by 18 cm each),with 5 cm high walls of 1.2 cm thickness. The entire maze is enclosedby an outside wall and the mouse isplaced at an outside square and must find its way all by itself to foursquares at the center of the maze.

This destination is so positionedthat wall-hugging mice will be unableto locate it. Of course, the maze is setup ahead of time and hidden fromview until just before the contestbegins. The mouse has 10 minutes tocomplete the run from the start to thecenter four squares where there is awooden goal post. Obviously, the

fastest mouse wins. Figure 3 showsthe maze at a contest at Cal StateChico. Note the detector protrusionsover the walls in both Figures 3 and 4.

One entry at a contest that I hadthe pleasure of judging back in 1988at Wescon featured a very uniquemouse. It could not have weighedmore than 100 grams and had a pairof sensor arms made from PC boardmaterial that extended over the wallson both sides of the maze paths. I’mguessing that the arms had a series ofIR photo transistors and IR LED pairsto detect the presence or absence ofwalls, and to keep the robot centeredin the path. This little sucker would zipforward and stop at each 18 cmsquare, examine the walls present,and would then proceed or quicklyturn a precise 90 degrees as required,and quickly step to the next square. It rapidly examined almost every possible square and found the centerfairly fast.

The amazing thing was when thecontestant placed the mouse back inthe square, the mouse quickly sped to the center four squares by theabsolute best route, sometimes making deliberate 45 degree turns to save time. Needless to say, it wonfirst place.For rules, check outwww.ieee.uc.edu/main/files/sac2007/mm_rules.pdf. There are manyother good sites that have both rulesand building techniques available.

FIRST — For Inspiration andRecognition of Science andTechnology

I could not write about robot contests without mentioning the verypopular FIRST competition that beganback in 1992 with 28 teams compet-ing in a New Hampshire high schoolgym. This competition series is thevision of one of my favorite roboticinnovators, Dean Kamen, best knownas the inventor of the SegwayTransporter. FIRST competitions are forhigh school students across the USand other countries. NASA and othermajor US companies have been long-time supporters of these events.

One example of a challenge wasone year teams competed against

each other by controlling their individual robots to push and passlarge rubber ‘Trackballs’ around thefield of play. (Two of the five winninghigh school teams were sponsored by NASA centers.)

The mission and vision of theFIRST Robotics Competitions, FRC, isdescribed this way, by Kamen:

“Our mission is to inspire youngpeople to be science and technologyleaders, by engaging them in excitingmentor-based programs that build science, engineering, and technologyskills, that inspire innovation, and that foster well-rounded life capabilities including self-confidence,communication, and leadership.”

BEST — BoostingEngineering, Science, andTechnology

BEST is also a non-profit, volunteer-based organization whosemission is to inspire middle and high school age students to pursue careers in engineering, science, andtechnology through participation in asports-like, science and engineering-based robotics competition.

Their vision is to excite thenation's students about engineering,science, and technology to unlocktheir imagination and discover theirpotential.

Final Results

I’ve only touched on a few of the more visible robotics contests. The many variations of BattleBots thatwas so popular a half dozen years ago on the Comedy Channel are stillheld across the world. Robot Sumoand other physical robot vs. robot contests are a mainstay of most robotorganization’s events. If any of thesecompetitions sound the least bit interesting to you, I encourage you togo to any of the hundreds of websitesfor information and help your owngroup of robotics enthusiasts developsome super fun events in your hometown. SV

Tom Carroll can be reached via emailat TWCarroll@aol.com.

FIGURE 3. Micromouse maze atCal State Chico contest.

FIGURE 4. Micromouse maze variations.

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