1. FTC Build a Better Robot
Cougar Robotics 4251

2. Design Principles and Strategies

3. Design Principles and Strategies
KISS
Keep It Super Simple
Tool Design First
Leapfrog Development
Never go backwards
Repetitive Testing
Competitive Development
Joey
Questions / Discussion
Leapfrog so you never go backwards
Strategy, build your robot to complement partners...

4. Practical Applications

5. Chassis/Drivetrain Stiff & Stable Frame Maneuverability
Rocker in a 6 wheel tank-drive chassis
Omni wheels on corners or one end
Ability to go where you want/need to for the game
Going the right speed
Practice driving before the tournament
Be prepared to drive on all parts of the field
Nathan
-don’t go in-depth on rocker
-omni wheels on the corners or at one end

6. Other Isolate your motors from impacts Torque > Traction
Mechanical Alignment
8 motors, 3 lego motors, 12 servos
Joey
Note for Joey: Put program on brick that tells robot to drive straight for 10 seconds or so.

7. Motor Power Table Motor Name Speed (RPM) Speed (Radians/Second)
Torque (oz/in)
Torque (Newton/meters)
Power (Watts)
DC 12 volt Motor
150 16
300
2.12
33.26
PF XL
220 23 56
0.40
9.11
NXT Servo
170 18 70
0.49
8.80
PF M
405 42 15
0.11
4.49
180 Servo 60 6 84
0.59
3.73
PF E
780 82 5
0.04
2.88
Continuous Servo 43 39
0.27
1.24
Evan
Need motor stats/limits
Should bring Ring It Up! arm

8. Double Drilled vs Regular

9. Tools, and Using them Color coding tools
Good mechanics have their own tools
Removing cross-threaded machine screws
Vice grips
Drill out
Removing rounded out machine screws
Easy outs
Sean

10. Building Practices Keeping screws and set screws in
Nylocks
Lock-tite and pre-nylon threaded set screws
Don’t transmit loads thru axles
Understanding friction/traction
Surface area doesn’t change friction
F=µFn
Components under tension & compression
Joey
Build both examples

11. Regular Wheel With Sprocket

12. Calculating Loads on Lever Arms
Margin of Safety
At least a 2:1
Exercise
Use a lever arm on your robot or make one including:
A DC motor
At least one gear change
A lever arm on the end
Using your setup, calculate the reasonable max weight your lever arm could elevate
Evan
Should bring Ring It Up! arm

13. Custom Parts

14. CAD Programs PTC Creo Pro Autodesk Inventor Gear Generator
Evan

15. Tools Laser Cutter CNC Machine Sheet Metal Shear Sheet Metal Brake
Polycarb and PETG
Sheet Metal Brake
Machine Lathe
Evan

16. Steel and Plastic When to use steel Your best plastics PETG Delrin
Polycarbonate
Joey

17. 3D Printing When to print your own parts
Web order 3D printing (Shapeways)
Some companies can print steel
Sean

18. Useful Websites Official Game Forum
Chief Delphi
ROBOTC Forum
Xander Soldaat
Cougar Robotics
Landroids
Sean

19. More Useful Websites Hitechnic http://www.hitechnic.com/
Lego Education
Digikey
McMaster-Carr
Sean

20. Contact Information
Coach Jamie-
Coach Judy-
Kids-