FTC Basic Design By Andrew Rudolph What are
FTC Basic Design By Andrew Rudolph
What are we designing? STRATEGY DRIVES ROBOT DESIGN NOT THE OPPOSITE!
What are we designing? The Road to Reality
2012 – 2013 Robot Rules Not the same as it used to be
Robot Rules 2012 -2013 • 18” x 18” – No weight limits • No mechanisms which: • • • Damage Playing field Damage or flip other robots Entangle Sharp edges Use hazardous materials
Robot Rules 2012 -2013 • Only can use preformed robotics components from: • Lego • Tetrix • Matrix
Matrix? • • • Designed to bring costs down of FTC overseas Designed off standard lego grid Different motors Different motor controllers Different Gears and wheels Observed at World Possibly thinner metal Championship exhibit Belt system CV Axles Check some of the offerings at: • http: //matrixrobotics. com
http: //www. chiefdelphi. com/forum s/showthread. php? t=106017 Matrix
Robot Rules 2012 -2013 • Only COTS (Custom Off The Shelf) items allowed: • Linear Slide • Non-motorized Turntables and Lazy Susan • Lead screws and threaded rod plus compatible nuts • Servo Blocks • #25 Chain and connector or half links
Robot Rules 2012 -2013 • Unlimited in quantity or size of the following: • Raw material available to all teams from standard • • • distributors Standard bearings or bushings Fasteners Rope, Cord, Cable, monofilament, … Rubber bands Latex tubing Zip ties Nonslip pad without adhesive backing Electrical solder, tape and any type of glue/cement Any COTS lubricant as long as it doesn’t get on stuff
Low Resolution Design You’ll get HDTV later
Low Resolution Design • Drawings
Low Resolution Design • Cardboard Mockups
The game piece • What can I do with this game piece? • What is the raw data on the game piece? • • Size Weight Center of Gravity Hard / Soft / Bouncy • Are there any unique features I can use to my advantage?
Sample Analysis. The • • Crate from 2011 -2012 9" L x 7 7/8" W x 6 1/8" H Covered in. 75” dia. holes Hard Plastic Ideal for organizing CDs, DVDs or smaller items in the office, bathroom or college dorm room.
What tasks within my strategy do I need to perform? • Are you going to… • acquire it? • manipulate it? • store it? • lift it? • position it? • release it?
The game piece • Think like a robot about the game piece: • What does the game piece look like from the robots POV? • What are all the ways the game piece could lay? • What is the most usable or stable position? • How does the object react?
Break time!
Drive Trains • • • 2 wd Casters / Omni wheels on end Difficult to drive Highly maneuverable Easy to get pushed Low payload
Drive Trains • • • 4 wd Easy to drive Can be low maneuverable Good pushing Easy to balance weight
Drive Trains • • 6 wd Drop center gives best of 2 wd and 4 wd Easy to drive Can be low maneuverable • (w/o drop center)
Drive Trains • • • Holonomic Maximum maneuverability Difficult to code / drive Easy to be pushed around Complex design
Drive Trains • • Tread Lower Center for maximum maneuverability FTC treads tend to slide Snap easily with side load
http: //www. youtube. com/user/FTC 5454
Mobility Analysis
Speed Reduction • Slower Speed Higher Torque • Higher Speed Lower Torque 221 robotics systems chain breaker
Mechanisms • Linkages http: //kmoddl. library. cornell. edu/ http: //www. mechanisms 101. com
Mechanisms • Lifts
Mechanisms • Complex stuff
Medium Resolution Design • Prototypes
CAD • No surprises when you build your real robot • Make changes quickly • Package your electronics! • Inventor • Solid. Works • Creo (PTC) • Use online tutorials, or take classes at Community College • • http: //www. catalogds. com/db/service? domain=fir st&command=show. Product&category=FTC_KOP& product=FTC%20 Kit%20 of%20 Parts Google Tetrix CAD
Paper Towers • Make the tallest tower you can • Must support at least 1 golf ball within 3” of the • • • tallest point • 3” bonus for every ball extra in top 6” of tower 1 Newspaper sheet 1 Strip of Tape Must be freestanding (i. e. cannot be taped to floors, walls, etc) Must pass a whoosh test Must spend 4 minutes minimum planning
General Design Tips • Maximize your “Acquisition Zone”
General Design Tips • Alignment Devices
General Design Tips • Use Nylock Nuts
General Design Tips • Keep your Center of Gravity low
General Design Tips • Will stray objects interfere?
General Design Tips • Make it easy to drive
General Design Tips • Design is an iterative process
Other Design Mantras • • Really, simple IS better Assume Nothing Sometimes wild ideas lead to champions You don’t have to prototype everything… …just the parts you want to work.
Resources Alro Metals Plus - Orlando www. alro. com 1101 Oak Lane Winter Springs , FL 32708 -2323 (407) 339 -2576 Metal sheet, extrusion, Aluminum, steel, brass, some plastics Can get new cut or from “drop” Mc. Master-Carr www. mcmaster. com Everything (i. e. bearings, bushings, hardware, tools, raw materials). Easiest website to find things on, fast shipping from Atlanta Warehouse, decent prices on most things. Grainger www. grainger. com Like Mc. Master but much more difficult to use catalog / Website. Has a few local storefronts that can help find part or even stock. MSC www. mscdirect. com Like Grainger Laird Plastics www. lairdplastics. com 4240 LB Mc. LEOD RD ORLANDO, FL 32811 407 -316 -0042 Full sheets of plastic, lots of options, might have to order in parts, much cheaper than most places. Fastenal www. fastenal. com Multiple Orlando Locations Hardware, in bulk, some tools, great prices. Skycraft Surplus www. skycraftsurplus. com 2245 W Fairbanks Ave Winter Park, FL 32789 If you’ve never been you’re missing out. Great place to get wires and other ideas. www. hansenhobbies. com Great kit for building your own PWM cables
Thank you.
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