Winning the International Botball Tournament: A TeamAnalysis

Daniel Honies1 and Daniel Swoboda2

Abstract— This publication introduces a set of bestpractices for the educational robotics competition Botballgained through long standing experience in the subject.Furthermore the publication gives an historic overviewof former Botball team items, the first non-US team towin the international Botball competition, and only thefourth to do so consecutively. The best practices weregathered by members of items over the course of a 4 yearlong competitive robotics career. With the publication ofthem, knowledge that can especially help new teams ismade available to all Botball teams therefore loweringthe barrier of entrance for new teams.

The first part introduces the Botball competition andteam items itself. This is followed by the 3 sectionsdescribing so called processes, each of them focusing onone area.

I. INTRODUCTION

Botball is one of the biggest school-focusedrobotics competitions in the world with over 250participating teams from more than 15 countries.The aim of Botball has always been to use roboticsto teach important STEM skills.[1] This effortcumulates in a competitive environment in whichstudents show off their robots in fiercely foughtrounds. Especially for schools with a long traditionin Botball, or those with the most knowledgeablestudents, a lot of the processes and knowledge re-quired to be successful in a competition is alreadypresent. However, teams with no such history orstudents lacking the experience have a naturaldisadvantage as they miss important informationand skills.

1 D. Honies is with Verein zur Forderung von Wissenschaft undTechnik an Schulen F-WuTSdaniel.honies at gmail.comrobo4you.at

1 D. Swoboda is with Verein zur Forderung von Wissenschaftund Technik an Schulen F-WuTS and RWTH Aachen Universitydaniel at swobo.spacerobo4you.at

Team items being one of the most recognisableBotball teams has gathered such skills and knowl-edge and therefore was able to successfully par-ticipate in various Botball competitions. By pub-lishing this information, the Botball game mightbe lifted to a new level as new teams can acquirethe theoretical knowledge needed to efficiently andeffectively manage themselves.

The processes introduced were fundamental toitems’ success but should not be seen as absolutebut rather one way to approach the competition,as many other teams have been successful withslight variations of the same techniques or evencompletely different approaches.

II. BOTBALL

Botball is a competition for autonomous robotsorganized by the KISS Institute for PracticalRobotics (KIPR)[2]. The main objective is to de-sign robots that perform a variety of tasks in 2minutes.

Scoring is based on 3 major elements:

• Documentation3 Files showing a teams ability to documenttheir progress have to be submitted through anonline system and are graded. Also an on-sitepresentation has to be given.

• SeedingA team has 3 runs on the table to score as highas possible. The 2 best runs will be averagedfor the score.

• Double Elimination (DE)Based on the seeding score a bracket fora double elimination tournament will beformed.

All 3 Parts contribute equally towards the overallscore.[1]

Fig. 1. items at GCER 2017

A. ECERThe European regional Botball tournament is or-

ganized by the Practical Robotics Institute Austria(PRIA), a Vienna-based organization for roboticseducation. As the tournament is part of the largerEuropean Conference on Educational Roboticswhich is partly funded by EU grants, it travelsaround European countries.[4]

B. GCERAn international Botball tournament is orga-

nized as the Global Conference on EducationalRobotics. The competitive program is extended bytalks of famous researchers and networking eventsfor students and teachers.[3]

III. TEAM

The team used as an example in this publicationis items. Located in Wiener Neustadt, Austriaitems had 6 members and an overall active Botballcareer of 4 years. The members of the team wereconstant throughout this time with the dissolve-ment of the team on graduation of their members.All of the members were students of HTL WienerNeustadt.

A. HTL Wiener NeustadtHTL Wiener Neustadt is a technology focused

5 year long high school based in Wiener Neustadt.Consisting of 4 departments (civil engineering,computer science, electrical engineering and me-chanical engineering) with the robotics club inthe hands of the computer science department.

Austrian technological high schools differ fromnormal high schools as they are 5 compared to 4years long and have a major focus on technologyand engineering with more than half of lessonsbeing related to the department students enrolledin. This leads to students having more than averageof theoretical and practical knowledge in their fieldof study.

B. History

items was founded in the first few months ofthe 2013/14 school year by 6 second-year stu-dents of the robotics clubs under the directionof Michael Stifter, PhD. The team members areDaniel Honies, Christoph Kaferle, Daniel Swo-boda, Markus Pinter, Florian Ungersbo”ock andRaphael Weinfurter. Starting with the 2014 Botballseason items participated alongside veteran teamAMAZeING at the European Regional Botballtournament in Vienna.

In the 2015 Botball season items participatedin both the European regional torunament in Hol-labrunn, Austria and the world championship inAlbuquerque, New Mexico.

The 2016 season led to items becoming bothEuropean and World Botball champion in Viennaand St. Augustine, FL respectively.

Their age-related last season was in 2017, withparticipation at the European Regional in Sofia,Bulgaria and the second World Championship titleat GCER in Norman, Oklahoma.

C. SuccessesCompetition Overall Seeding DEECER 2014 4. 3. 7.ECER 2015 3. 1. 13.GCER 2015 5. 5. 6.ECER 2016 1. 1. 1.GCER 2016 1. 1. 1.ECER 2017 2. 3. 3.GCER 2017 1. 2. 1.

IV. TEAM PROCESSES

In order to be a successful teams a varietyof internal team processes have to be managedand planned out well. These processes are keyregardless of the size of the team.

A. Motivation

While being successful at a competition andhaving fun while working on the robots is by itselfa big factor in team motivation, there needs to besome sort of motivation management to overcometeam-wide downs.

A big goal and achievable goal (e.g. Participat-ing at GCER or being under the top 10 in Seedingat my regional) should be agreed on by all teammembers and worked towards together.

Team members lacking in motivation shouldalways be encouraged by other team members tocontinue their work by highlighting the greatergoal of the team and or recent successes in thedevelopment of the bots, be they very small.

Another big factor to motivation is a second in-house team. Having a constant measure in progressby a team working in the same environment canbe a big deal whilst trying to stay motivated.

B. Organization and Management

There is no go-to solution for team organizationas it varies on a lot of factors like resources,team size and team experience. However there arecertain key factors that should be considered by allteams.

It is important to have either no person withmore authority than others (democratic/anarchichapproach) or a set of people with clearly definedauthority that the whole team respects (captainsapproach).

Team members should communicate with theirpeers as much as possible, explaining decisionsand avoiding an information void.

Roles should be clearly defined and work insmall sub teams encouraged and favored overpeople working alone.

Meet-up dates should be clearly defined and at-tendance required. Frequently missing people andmembers working significantly more than othersshould be avoided as it may cause unrest.

Enough time should be dedicated. This needs tobe adjusted based on team size, amount of robotsand strategies, etc.

C. Division of Labor

With many unique characters with different pos-sibilities coming together in a team, it is important

to make sure that each talents are used as effectiveas possible. People working in their field of interesttend to do better on assigned tasks and come upwith more creative solutions. That said, it shouldbe encouraged in later stages of development thatmembers of different fields of expertise engagewith each other to boost creativity.

V. PRE-COMPETITIVE PROCESSES

A. Strategy

1) Seeding: For the seeding strategy usually2 team members studied the game review verycarefully and at first only came up with a fewtasks which would score very high and are nottoo risky. They then proposed those ideas to theirother teammates and together the team figured outwhich tasks could be done by which robot.

By combining several lower scoring tasks in-stead of completing only one very high scoringtask the risk of a strategy can be lowered dras-tically as the score will still be high even if onepart fails. Furthermore the risk sinks if each robotsolves scoring tasks solely and isn’t depended onthe other robot. At an optimum one robot wouldscore at one side while the other one would scoreon the other side.

2) Double Elimination: In Double Eliminationit is even more important to run consistent than inseeding. Therefore for their main Double Elimina-tion strategy items usually adapted their seedingstrategy only slightly so that all the adjustmentsfor their seeding runs could be used in doubleelimination as well and they would only score ontheir side.

Whenever it was clear that the opponent teamwould stay on their side and not run a disruptor andtheir theoretical score was lower, items would trusttheir seeding bots and run a high scoring strategy.

In the event of another team running a disruptorbot, items would try to not run the bot which thedisruptor is targeting but instead run a disruptoritself which would target the remaining bot ofthe opponent team. Following this concept, itemshas still one scoring bot while the other team hasnone. It is essential to not block vice-versa as theoutcome would solely be based on luck whichshould be avoided at any circumstance.

Disruptor Bots: Disruptor Bots need to be eithervery big with long extendable arms or they needto have a creative way of overcoming the obstaclesin the middle of the board effectively and fast.Both versions are very hard to achieve consistentlyand can take as long as a seeding strategy todevelop even if they might look like surprisinglyeasy builds.

Anecdote: In the 2 GCER DE Tournamentsitems won, they only ran a disruptor in 2 finalmatches. A high scoring adaptable seeding strategywill usually get one way further than the mostcreative disruptor bot.

B. Documentation

The Botball Team Homebase provides very clearrules for the documentation phase. Also severalexamples of perfect documentations are given andvery well commented. Therefore its very easy toscore perfect on these and a minimal effort shouldbe put to those if a team is serious about winningthe tournament.

C. Robot Hardware

Items used a few core principles whenever a newrobot was designed.

1) Robustness: Robustness is one of the mostimportant principles when aiming for a consistentrobot. If a robot isn’t sturdy, its actuators won’thave the same position every run. If it crashes, itsactuators have to be re-calibrated. By using screwsinstead of connectors, legos can be connected morerobust and whole subsystems won’t fall off evenif the robot encounters unexpected barriers duringthe run.

2) KISS Principle: Actuators are supposed tobe build as simple as possible. This reduces the riskof mechanical failures and a more simpler LEGOconstruction is almost always sturdier than a verycomplicated one.

3) Specialization: Actuators that are modifiedexactly for one purpose can reduce programmingtime by magnitudes. There is a 1000 different waysto grab an object and usually the first try doesn’twork best. Not being fixated on one solution andtrying several different approaches might save timein the end.

Fig. 2. Special claw mechanism used to grab the cow in the 2017game

4) Modulation: By building different subsys-tems for your robot which can be switched effort-less, a lot of time building new robots can be savedwhile various strategies can still be realized.

D. Software Development

1) Pair Programming: Especially in laterphases of the development of a bot, the peopleresponsible for building the bots tend to have lesstasks on their schedule. By working with them andusing the concept of pair programming they can bea second set of eyes watching the bots as well assomeone who critically questions decisions. Thiscan help to find flaws in the strategy and theprogramming, therefore improving overall quality.

Making use of this programming strategy waskey for a successful cooperation between the dif-ferent sub-teams of items and a fast and reliabletesting method.

2) Orientation and Positioning: Pipes are aneasy way to align your robot. Especially in thecorner of the game board they can be used toaccurately achieve absolute positioning. This canreduce the amount of sensors needed and thereforeremove factors of uncertainty from the strategy andprogram.

Pipe based orientation was used extensively byitems.

3) Strategy Time Management: Managing thetime dedicated to different parts of a strategy isone of the most important tasks in Botball. Itemsrelied on multiple ways of managing the limitedtime available to the bots. One of the key aspects

was the use of multi-threading (as described later)and adaption of drive speeds. Both allow a vastreduction in time-consumption of a strategy. Inorder to synchronize the two bots on the table,time and sensor based events were used.

4) Fail-safes: In order to increase the perfor-mance and stability of a robot, items relied on fail-safes at critical points in the program. These fail-safes were activated when certain criteria were notmet and activated a fail-safe program that eitherrepositioned the robot or skipped to the next pointof the routine.

Such a fail-safe can be critical for both Seedingand Double Elimination strategies and can safe arun from ending up in disaster. It is recommendedto implement fail-safes.

5) Mulithreading: Multi-threading can be acore concept to save time and therefore a keyfactor to increase the amount of points that can beachieved. It’s applications can vary from prepar-ing the position of an actuator while the robotis moving to a different location to performingmultiple tasks at the same time. It is howeverimportant to keep in mind that multi-threading canlead to unintended behavior and therefore requiresmindful coding.

E. Consistency by Design”complicated robots flash draw crowds on prac-

tice day, but simple reliability wins the tourna-ment.”

Consistency is a core fundamental of every as-pect of a strategy and a robot. If testing shows thata sub-procedure cannot be repeated successfully9 out of 10 times on your own table, it is toorisky to be run at a tournament. Subsystems canbe redesigned or a new strategical programmingapproach might work out. Sometimes adding asimple sensor can increase consistency a lot. Ifa system didn’t work consistently after 2 weeks,it was usually dismissed and the strategy wasmodified.

F. TestingTesting was usually done that one strategy

would be programmed after another. The strategieswould be programmed step by step, making surethe program works consistently before continuingwith the next part. This approach safes a lot of

time as a simple hard- or software change at thebeginning can result in the whole program beingneeded to be recoded. Endless hours of testingshowed that what worked best for the team was2 people testing one robot. One being the primaryprogrammer would compile and start the programs.The other is continuously setting up the table androbot. While the robot runs, both would togetherdecide on what values need to be changed andwhat the next step for the robot should be.

VI. COMPETITIVE PROCESSES

A. Effective Human Resource ManagementTo succeed at a tournament it is essential to use

every member effectively in what they are bestat and in a configuration where people can worktogether under stress without creating too muchconflict.

The team had 4 people testing the robots in pairsas usual and 2 students focusing on informationgathering. While one member keeps an eye on thetesting table, the other one would have a closerlook at the robots in the pit-area for possibleconstruction violations.

It is essential for one student to get a generaloverview. They need to know most teams andtheir respective robots so they can later delegateon which teams to film in seeding or doubleelimination.

B. Information GatheringDuring their four years of Botball items exper-

imented with different ways of getting and stor-ing the necessary information about other team’sDE strategies necessary to win a tournament. Itwas tried to write everything down on paper byseveral people. In the second year the team evenprogrammed a web application which stored thesame information as the paper but with the addedbenefits of supporting pictures and videos. Ulti-mately after all of this approaches did not seemto provide critical information when needed andrequired an enormous amount of maintenance, theteam settled with a way easier method:

For teams that were considered very good andwhere a special DE strategy was needed, the teamtried to film them at seeding and store those fileswith the team name on one computer so they canbe analyzed together later on.

During DE one or two people always monitoredand mostly filmed the matches which where goingto decide the team’s next opponent. If the teamwasn’t one where a special strategy was createdfor, all members simply gathered together and de-cided on the basis of the just obtained informationon which strategy to run.

C. On-Site

Items always put their presentation togetherbased on the grading list given on the TeamHomebase and printed it out on standard letterpaper. It is advisable to double check especiallyon the graph and figures part as those score highand it is easy to lose points there.

Also bringing the grading list to the presentationis allowed and can help not forgetting any pointsthat may not be in your presentation directly.

One should be able to score at least more than95 points on the on-site if carefully prepared but itsalways hard to score perfect as you or the judgesmight miss a small detail.

VII. CONCLUSION

Botball is a dynamic and competitive environ-ment. This publication and the insights sharedthrough it are a first step into enabling youngerand less-experienced teams to be more successfulin a shorter amount of time. Such change wouldincrease the overall competitiveness of the compe-tition and therefore raise the level of knowledge ac-quired through participation for all teams. Uppingthe level of Botball therefore profits all teams, asit increases the complexity for experienced teamsas well, who would have to face new challenges.

The authors would like to encourage more se-nior teams to release their insights, strategies andprocesses. Such information could then be madeavailable in a knowledge-base for the benefit ofall teams.

ACKNOWLEDGMENT

The authors would like to thank their coachand mentor Dr. Michael Stifter for his continuousguidance throughout their active Botball career andhis organization and funding efforts that made itpossible to participate in the Botball program.

REFERENCES

[1] http://botball.org[2] http://kipr.org[3] http://new.gcer.net[4] http://ecer.pria.at