Putting the "Spin" on a Robotic Sailboat

A couple weeks later, Miller registered another important milestone and filed another update.

"Spin sailed under full servo-control of mainsail and jib today. This achievement has taken over a thousand man-hours to achieve...from a boat that was perfectly usable last year but fully manually controlled. I was onboard pushing joysticks & buttons making sure everything went smoothly. Sailing by digital joystick takes getting used to, especially in the tight maneuvering space of the Auckland Viaduct. Spin can tack in 3 seconds. The only technical issue was an unpleasant noise from the auxiliary motor/hydroelectric generator when pushed to 20 amps output. Next time I won't scrimp on that critical component.

There are many months of work to do before she's autonomous and net-energy-positive, but it's a good start. The Sailvision worked from initial installation last year. Next projects are waterproofing, mainsail furler, instrumentation, and telemetry. This afternoon it's time for a few rums and Foo Fighters in The Spin Lab."

With no end in sight regarding the current America's Cup imbroglio, Miller reckons his work on Spin will continue unabated. He plans on lightening the keel and fashioning a bolt-on extension to address increased righting moment with the addition of a new, untried, square-top mainsail. Participation in the 2010 World Robotic Sailing Championship is a strong possibility. Fund-raising is something that needs attention‚ "I'd love to find a sponsor like Parallax, the company that makes the microcontroller chips that Spin depends on"‚ but otherwise, the work continues.

I have to confess that much of what Miller has explained to me has, quite frankly, totally escaped my complete comprehension. I guess maybe he was thinking of me when he offered the following: ‚"The name Spin works really well on many different levels for this project. Spin also stands for Science Project for Instrumentation and Navigation. I can also say to people, "Go ahead, take her for a Spin" or "This crazy project makes my head Spin!"

That I understand.

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Here is what Spin has and does:  

    * Four onboard Parallax Propeller microcontrollers perform sail control, system monitoring, and navigation
    * Each Propeller resides on a custom Spin Controller PCB designed by Miller
    * Each Spin Controller supervises up to four motors/actuators and has 16 12-bit A/D channels
    * Sail control lines (sheets) and rudder are controlled using 7 gear motors and 3 linear actuators (so far)
    * Each motor has a dedicated motor controller receiving packetised serial commands from a Spin Controller
    * Each winch's position, velocity, current, and motor temperature is measured at 30 Hz.
    * Motor end limits, home position, and max current stored in EEPROM
    * Spin Controllers simultaneously accept manual joystick, R/C PWM, and telemetry commands
    * Auxiliary propulsion is provided by a 600-watt trolling motor that also generates power while sailing
    * Navigation system includes AHRS (heading, heel, pitch), GPS, four boat speed sensors, and three anemometers
    * Communication system includes 900 MHz long-range telemetry and 2.4 GHz Wi-Fi.
    * Spin also has onboard cameras that measure sail shape in near-real time (a.k.a. Sailvision)
    * Spin is carried on a motorised trolley with dual 24V, 60A gear motors. Trolley can pull 300 kgs horizontally for going up gangways from floating pontoons.

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