OVERALL ROBOT DESIGN, FTC STYLE

PRESENTED BY:

ANDY BAKER

Sept. 2015

WHY SHOULD YOU LISTEN TO ME?Andy Baker

• President and co-owner, AndyMark• Founded in 2004• Crown Supplier to FIRST• andyb@andymark.com

• FIRST Mentor• FRC mentor: 1998-current• FLL mentor: 2012-current• FTC mentor: 2009

• Mechanical Engineer, University of Evansville, ‘91• FIRST Championship WFA winner, 2003• Husband, father of 3 teenage daughters

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THE ENGINEERING DESIGN PROCESSA method for solving a problem

Can be modified to suit the problem at hand

An iterative process

FIRST is an excellent opportunity to learn and practice this process!

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PROJECT PREPARATION: GET READY!Determine team goals

Know your resources, strengths and limitations• Design and manufacturing skills• Build location

Set schedule and expectations

Determine concept design groups

Determine leader to steer and manage design decisions

Before Kickoff

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DEFINING THE FTC CHALLENGE

Watch kickoff as a team

Everybody should understand the FTC Game Manual rules

• Read sections aloud to each other, as a group

Create lists and charts• Robot design constraints

• Maximum size, allowed materials & components

• How points are scored

• What actions are not allowed during the game

Kickoff

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THE CRITERIA FOR AN FTC ROBOT

Build a field• Buy field components you choose (certain parts / half field / full field)• Build a field using DIY instructions

Breakdown the game, understand the different strategies• Create a mock game (white board, board game, full scale with people)• Create a chart of the various scoring methods and the points awarded• Estimate the time needed to score points

Determine how the most points can be scored in the game• What actions carry a disproportionately large number of points• What actions may not be worth the risk

Create a list of what the robot should be able to do• The answer can end up being “Everything”• Rank features by order of importance for now• Quantify requirements: How Fast? How Many? How Far? How Long?• Keep track of this, as things can change later as more is learned

Weeks1 &2

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DEVELOPING FTC ROBOT CONCEPTSBrainstorm!

• Ideas may be for only a component, not necessarily a full robot concept

• Keep designs high level, don’t go down rabbit holes worrying about how it will be built

• Ideas don’t have to be on paper, use simple building tools to model concepts (LEGO, cardboard, PVC pipe, wood, foam board)

• Focus on accumulating as many ideas as possible

• All ideas are good

• Don’t criticize each other’s ideas

• Look at how various concepts may work together

• Often even more concepts will arise out of this discussion

Weeks1 &2

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HOW TO DECIDEReview concepts against criteria and constraints, estimate their ability to meet them

Compare relative complexity of concepts• Number of moving parts / degrees of freedom / failure modes

From this analysis the leading options should begin to be evident

Use a decision matrix to further rank ideas

Have one focused concept, but have 1-2 backup options as needed

Have one person responsible for overseeing and enforcing final decision

• Put-aside method from Mr. Bill

end of Week 2

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DECISION MATRIXEnd of Week 2

Attribute Weight

1-5 Rank 1-5 Rank 1-5 Rank 1-5 Rank 1-5Speed 4 4 16 5 20 2 8 5 20Power 4 3 12 4 16 4 16 5 20Score-ability 5 4 20 5 25 3 15 5 25Reliability 5 5 25 2 10 5 25 1 5Defense 3 2 6 4 12 5 15 5 15Easy to build 5 5 25 2 10 5 25 1 5Innovation 2 2 4 4 8 1 2 5 10Wow 2 2 4 4 8 1 2 5 10Total points 112 109 108 110

Sub-TeamsBlue Red Black White

Simple robot, known designs, can score well

and defend OK.

Complex robot, stretch designs,

does all functions well if they work.

Simple robot, no risks, using

easiest designs.

Complex robot, very risky

designs, can do it all if it works.

DEVELOPING ROBOT PROTOTYPESAssign Design Groups

• Chassis, appendages, structure

Build prototypes• Make many• Keep things simple (KISS)• Use alternative materials to speed construction• Keep records of results (pictures, video, sketches, etc.)

Design• CAD concepts• Assign motors, actuations, sensors• Figure out gear ratios, keep your options open

Iterate• Break it, fix it. Rinse and repeat!• Pay attention to new ideas which pop up here

Change is still easy at this point

Conduct weekly design reviews, communicate results

Weeks 3 - 5

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DETAILED DESIGN

Use prototyping results to finalize design• Use CAD or detailed drawings for all parts and dimensions

• Keep designs within the manufacturing capabilities of the team

Hold regular design meetings between groups• Track packaging issues for each component as designs develop

• Finalize motor use

• Include transition points between dependent mechanisms designed by different groups

• Design in sensors, wiring, connectors

Buy materials and parts that will be needed

Weeks 5-7

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FABRICATE & ASSEMBLY

Design in aesthetics• Powdercoat• Anodize• Paint• Color of materials

Groups finish designs & reach this stage at different times• Drive base done first• Weigh it down during testing

A more complete design will speed assembly

Electrical • Mechanical contacts and connections• You are all systems engineers in training.• Reliability: make things neat, color coded, labeled

Weeks 6-8

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TEST!

Test drivetrain early• Weigh down drivetrain to 40-50 pounds, drive it on Soft Tiles

Begin testing components as they come together• Break it early!• Early breaks = early fixes

Program, drive, and test as much as possible• Install automodes• Break it early!

Celebrate breaking things!

Plan for things to fail or break. • Take time to iterate designs and re-build components that do not

work as planned.

Weeks 8-9

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PRACTICE!

Practice

• Practice, practice, practice and then practice

Break it again

Practice some more

• Practice, practice, practice and then practice

Break it again!

Oh, and tweak your code

Weeks 10-12

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COMPETE AND UPDATE

Get as much done before competition as possible

• Plan your logistics well so you can focus on improving the robot• Finish your robot! The earlier you pass inspection at the

competition, the better your chances are to compete well.

Watch events to determine which designs work well

• Improve your designs, learning from what you see• Fabricate improvements

Watch other events to determine winning gameplay

• This helps focus practice

Have spare parts created and available at competition

2 weeks before

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HOW LONG SHOULD THIS TAKE?Timeline Task

Before Kickoff Determine goals, schedule, resources, leaders

Week 1-2 Understand game, Quantify points, Create list of robot tasks

Week 1-2 Brainstorm, Critique, Present, Decide on concept, Put-aside

Week 3-5 Assign design tasks, Finish prototypes, Begin CAD, Assign actuators, Buy needed robot items

Week 5-7 Finish Drivetrain CAD, Build Drivetrain, Finish programming structure, Finalize appendage designs, Drive robot, Design graphics and aesthetics

Week 6-8 Finish fabrication of all parts, Break things, Install wiring, Implement programming

Week 8-9 Break more things, Install automodes, Get appendage mechanisms to work

Week 10-12 Break and fix appendages, Practice, Install paint and graphics, Ensure spare parts are made

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THANK YOU!

Questions?

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