Mentors WorkshopElectrical Sub-System

Mark McLeodTeam 358Festo/Hauppauge H.S.

FFor

IInspiration and

RRecognition of

SScience and

TTechnology

Objectives

FIRST Rules & Restrictions Official Suppliers & Other Sources Basics/Components Design Notes Potential Problems Keeping Students Busy Typical Schedule Sample Layout

FIRST Rules & Restrictions

Kick-off Rules FIRST Wiring Diagram Wire gauge Grounding Allowable divergence Part of $3500 limit (2005) on additional parts No single electronic component > $200 Inspectors rule – volunteers and all that implies

Official Suppliers & Other Sources

Official Suppliers www.innovationfirst.com/

Other Sources www.jameco.com www.mouser.com www.digikey.com www.future-active.com www.newarkinone.com www.radioshack.com

Simplified Circuit Diagram

12V SLA Battery

CircuitBreakerPanel

120A Circuit Breaker- +

Ground Stud

Robot Controller

Victor 884Speed

Controller

SpikeRelay

BackupBattery Modified Diagram by Steven Shade, Team 1111

Note: No control system wiring is included

Basic Components

•Main battery (12v)

•Wire gauge – 6, 10, 16 & 24 awg

•Spikes (forward/reverse/off)

•Victor speed controllers (coast, brake, calibrate)

•Motors, fans, compressor

•Circuit breakers – 120a main, 20/30/40a panel

•Ground stud

•Control system (7.2v battery)

•Servos, solenoids

•12v sensors -- current, banner

•Motors

Design Notes

Diagram robot electrical layout Access to all components for test and

replacement Control System status lights and buttons visible

and accessible Battery mounted securely and is readily

removable Weight of wire -- short wire runs Crimp & solder, label all wiring, connections,

fuses Neatness counts – tie-up cable runs (electrical

tape for insulation only)

Potential Problems

METAL SHAVINGS (cover electronics) Blown components Welding robot frame w/electronics attached Wiring loose/poor connection (PWM cables too) Victor Speed Controller calibration Overheating motors -- additional fan cooling LockTite melts plastic – controllers, spikes Breaker resets from stalled or improperly

geared motors

Keeping Students Busy Variations on robot electrical layout Develop basic skills

Circuit basics, e.g., series & parallel Advanced circuits, e.g., IR beacon, CMU camera, or

external processing circuit Use of multi-meter Learn to crimp & solder

Heavy components Delicate electronics (heat sinks) PWM and electrical connectors

Debugging techniques Projects

Battery charging station FIRST power connectors on battery charger Test bed

Typical Electronics Schedule

September thru December Develop basic skills

January thru March Six week build period

Robot design – space for electronics and wire runs Motor/sensor requirements Designing and testing solutions Resolve physical layout Integrating solutions with mechanical

Regional event Inspection