Teacher/Mentor Institute Hands-On Session: Building a Robot Scott McEwen & Kevin Barrett July 21-22, 2014

Overview  Quick and simplified exposure to what your student team will experience  You will experience some of the same  Design choices  Building decisions  Learning experiences  Frustrations  We hope that this will make you a better coach and mentor! Page 2

Caveats This guide has a suggested procedure for building your robot. You may vary from this procedure so long as you:  Do not endanger yourself or anyone else  Do not permanently attach anything to the Returnable Kit parts  Do not damage the room or furniture in any way  Clean up after yourself Page 3

Be courteous to our hosts!  Please DO NOT scratch the tables, other furniture or floors, or snag any carpet or furniture fabric  Keep a box lid or other surface protector between your work and the furniture or floor Page 4

The Competition  Two robot teams per match; multiple matches.  Game Field:  Bounded by PVC  Small & big balls  Two buckets (one per team)  Score by placing balls in your bucket.  Small balls = 1 point each  Big balls = 2 points each Page 5

Platform (1) Construct/Attach:  Plywood base  Motors  Skid Make sure the platform is stable and can roll in various directions. Page 6

Platform (2)  Attach Cortex Page 7

Connect Motors to Cortex (1)  Motor Ports 1 & 10 – Built-in motor controller. Not allowed by BEST.  Motor Ports 2-9 – Require external Motor Controller. BEST requires use of ports 2-9.  Motor Ports 1-5 share same overload circuit protection, and Ports 6-10 share same circuit overload protection. Balance motors between ports 1-5 and  Use Screw Terminal Motor Interface Page 8

Connect Motors to Cortex (2)  Cortex Motor Port  Motor Controller  Screw Terminal Block  Motor wires with Quick Connects  Motor Tabs Page 9

Test the Platform (1)  easyC: File … New Competition Project  Field Control Competition Project  Operator Control tab  Joystick … Arcade- 2 motor into while loop Forward/Reverse Channel: 2 Rotate Channel: 1 Left Motor, Right Motor: (look where you plugged these in to the Cortex.)  Joystick … JoystickAnalogDeadband => before Arcade  Deadband for both Channel 1 and Channel 2  Test-“drive” the platform – make sure the motors respond correctly Page 10

Wheels  Attach hubs to wheels  Attach hubs to motor shafts Page 11

Arm  Build and attach A- frame to hold arm  Make and attach an arm that is the right size to:  Reach to the ground  Be pulled down by the winch Page 12

Winch  Build and attach winch  Mount and attach winch motor  Wire winch motor to Cortex  Edit your program to include winch motor  Test  Add spool and string to winch and test again Page 13

Test Drive 1. Go to Build and Download menu. Compile your program. Fix any errors. 2. Connect USB cable between laptop and Cortex. Download your program to Cortex. 3. Tether joystick and Cortex – Connect them with USB cable. 4. Turn on Cortex first, then joystick. Wait for ROBOT and JOYSTICK lights to turn green. 5. Test each wheel motor forward and backward. If either wheel moves in the wrong direction, go back into the program, check or uncheck the box to reverse direction, and try again. 6. Untether the Joystick and Cortex. Turn them off. Insert the 2 VEXNet keys and turn them back on. 7. Drive the platform without the tether. Page 14

Servo  Connect servo to Cortex with a Servo Controller  In your program, add a JoystickToServo, and use Channel 5 or 6  (Servos don’t need a deadzone)  Turn on Cortex and Joystick. The Servo will rotate to its “zero” position. Make a note of it. Page 15

Claw  Disconnect the servo from Cortex.  Design and assemble claw, including servo. Make sure it can move properly.  Remember to assemble it so that its starting position coincides with the servo’s “zero” position.  Reconnect the servo to the Cortex. Turn Cortex on and test claw. Page 16

Mount the Claw  Attach the claw to the end of the arm.  Make sure it reaches to the ground and can open and close.  You may need to add a servo extension between the servo controller and the servo. Page 17

The Competition  Two robot teams per match; multiple matches.  Game Field:  Bounded by PVC  Small & big balls  Two buckets (one per team)  Score by placing balls in your bucket.  Small balls = 1 point each  Big balls = 2 points each Page 18