New? See the Hardware Learning Guide for a list of important wiki pages!

The Hardware section of MAST handles everything with power, circuits, and sensors. This page should include information on

  • RS232
  • TTL
  • Serial communication protocols, ie 8N1
  • Noise reduced design (ie ground loops)
  • Electrostatic protection and why
  • Batteries (charging, discharging, voltage curves)
  • Present design of the boat and equipment used

Timeline 2010/2011Edit


  • Find how to charge RC boat's batteries
  • pololu (serial motor controller)
    • RS-232 COM microcontroller cable (microcontroller is serial levels)
    • can be driven by RS232 into RS232 level input. Or TTL level or CMOS levels into the logic-level input.
    • output is 5V logic we think... look into whether there are 5V serial inputs on the microcontroller to read the responses back from the Pololu (not RS232).
    • multiplexer needs to be connected to 3 pin outputs from the Pololu
  • look up microcontroller signal levels and pins
    • all COM ports RS232 level?
    • all digital I/O pins 3.3V level?
  • clean up multiplexer circuit (RC/uC -> motors)
    • put headers on all wires
    • make wires to connect to pololu motor outputs
  • clean up the power portion of the multiplexer circuit
    • evaluate the current draw from the motors and fuse accordingly
    • fuse the smartwinch power circuit
  • box layout (february task)
    • determine all components that have to be in the box first
    • determine boat size
  • replace old elec power circuit
  • look into low voltage shutoff (MAX696EPE+-ND)
    • read user manual
    • test hooking up a dummy load and adjusting voltage cutoffs
    • plan how to use it to cut off unecessary loads/cut off power to all components when the voltage is dangerously low; send feedback signal
  • eagle as you go (teach)
  • mini solar system testing - solar powered compass!
    • research options
    • design system to power compass to start
    • basic testing off boat
    • mounting (waterproofed?)


Sept - Recruit, meeting 1&2 (intro and teaching about systems basics), referendum?, teach eagle (meeting 3), set research goals

  • Sept 16 - Open House, recruitment, email list signup
  • Sept 23 - Overview of control system, LED circuit and soldering session
  • Sept 30 - Run down of multiplexers and how they are used in the boat

Oct - Research the options, decide general course of the year (tasks); construct prototype of power and control;

  • Oct 7 - Explanation of how voltage regulators are used, how we use capacitors to reduce error, soldering three of these small circuits
  • Oct 14 - Construct prototype of power and control system
  • Oct 21 - Integration of power and control prototype with Arduino and servos
  • Oct 27 - Power Calculations (requirements), solar power

Nov - Design: ELEC Box Design, Battery Locations, Wiring in Boat

  • Nov 4 - Specific design/drawings of ELEC Box, inputs/outputs locations on box

Dec - Exams/final designs/order parts for final design

Jan - Construct final power and control system; C Blair 11:09, January 6, 2011 (UTC) construct ballast prototype (talk to Cory to see what he wants to do for the ballast this year)

Feb - Complete build; C Blair 11:09, January 6, 2011 (UTC) Land test power, controls, sensor systems; if no problems -> solar panels, turning off sensors/motors depending on battery levels, camera, replacing NMEA combiner box, other performance tweaks, wireless arduino programming (this will have HUGE payoffs during competition in performance tweaks), start satellite communication research (SPOT messenger?), AIS

March - Final build fixing

April - Water testing on weekends

May - Compete!

Useful PostersEdit

  • RS232, TTL, CMOS signals Serial Nick

RS232: inverted 12V logic, 0=+12V, 1 = -12V, also has a serial protocol associated which specifies at least a ground TX (RX) lines (other lines for handshaking are CTS, RTS)

TTL: 3.3V OR 5V logic, 0=0V, 1 = 3.3V, requires a ground and signal, no protocol associated

  • What are all the wiring harnesses, pins, powers, baud rates, etc of the compass and wind sensor? Nick
  • Soldering Guide
  • Serial port communication (combine with signal level info above?) Serial Nick
  • Resistor color codes Media:Resistor_Color_Chart.pdf Nick
  • Circuit diagram symbols [1] Electronics Components Nick
  • Null modem/Loopback full schematic Serial Nick
  • Low noise design (ground loops, antennas, crosstalk)
  • Electrostatic Discharge Protection
  • Typical things to troubleshoot - it's usually the power, or the power and signal grounds arent connected. If not, look into shorts, discontinuities, and blown chips on the boards
  • Parts of a datasheet Nick
  • Battery charging, maintenance, and TLC Power

Timeline 2009/2010Edit

September - recruit, referendum

October - inventory, user manuals

November - set design goals, research and design to address waterproofing, power management

December - preliminary designs and budget

January - Order parts

February - Construction starts

March - Construction

April - Construction

May - Merge with Software

June - Competition

July - Document

August - Document, prep for 2010/2011

External LinksEdit

All items (43)

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