RWU SailBot

Presenters: Philip Bourque, Nate Brodrick, Maria Mangiameli

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Additional Team Members: Nick Tinglof, Grace Harting, Chris Maseda

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Advisor: Dr. Gordon Stewart

Meet the Team

Course

• ENGR490 & ENGR492

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Composition

• 5 Mechanical
• 1 Electrical/CS

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Maria Mangiameli

Electrical & CS

Nicholas Tinglof

Mechanical

Chris Meseda

Mechanical

Grace Harting

Mechanical

Philip Bourque

Mechanical

Nate Brodrick

Mechanical

Our Philosophy

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KISS “keep it simple sailor”

• Recycle materials
• Hull from WPI
• Old kite for sail material
• Pre-Existing design
• Sail
• Rigging
• Mast/boom
• NACA airfoils
• Keel & bulb
• Rudder
• Minimal coding

Major constraints:

1. Time
2. $811 budget
3. No sailors on the team

Work Distribution

Electronics &

Software (Maria)

Rudder (Chris)

Work Distribution

Keel & Bulb

(Nate & Philip)

Additional Work

Finances

(Nick)

Meeting Minutes

(Grace)

Boat design:

Naval Architecture

Hull

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Hull graciously donated by WPI

Alterations Made

• Mast Relocation
• New Mast step
• Paint & fiberglass work
• Attachment points for the rigging
• Windvane attachment

Initial

Final

Keel

For the keel shaft, our design options were limited by the existing hull geometry. So the easiest solution was to utilize that location and size.

Using a website called airfoiltools.com we were able to create different CAD designs to see which would fit our steel bar best

The airfoil for the keel shaft was manufactured using a steel bar that fit in the slot with a 3d printed NACA airfoil sleeve

Keel Bulb

Requirements:

• 6 kg Mass
• Symmetrical Airfoil
• Thickness/Chord Ratio of 10

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Design:

• NACA 0010 Airfoil
• Lead Filling with 3D printed Bulb

Mast

• Carbon Fiber Tubing vs. Aluminum Tubing
• Calculate deflection to decide best diameter for criteria

The original mast step was located towards the front of the hull. For our design, we needed to move the location of our mast further aft to align the center of effort with the center of lateral resistance and maintain neutral helm

Mast Location:

Sail

DF95 mainsail with jib

• Used the sail shown from a 1 meter RC sailboat and scaled it to fit our boat
• Bermuda shaped mainsail

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Material: ripstop nylon recycled from a wind kite, reinforced at corners, grommets added

Rudder

• 3D printed PETG sleeve over aluminum rod

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• NACA 0021 airfoil

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• ~5% of sail area

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• Aspect ratio ~5:1

Boat design:

Electronics

Electronics Overview

Ground

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Sailbot

MATEK Aircraft Flight controller

Winch servo

Windvane

Telemetry

Rudder

servo

RC

GPS

12V battery

ArduPilot Mission Planner

Inputs

Windvane

GPS & Compass

Flight Controller

Compass

I2C

Analog input

GPS

UART

Outputs

Winch

Rudder

Flight Controller

PWM

PWM

Boat design:

Controls & Communication

Communications

RC &

Telemetry

Flight Controller

UART

Ardupilot

• Open source autopilot system
• RC & Autonomous connection to boat

Lessons Learned

The Good

• Boat sailed very well! Responsive and fast
• The flight controller was a great plug and play solution
• When we got auto mode working, it was able to complete an endurance lap
• We learned a ton!

The Bad

• Initially could only change autopilot settings via USB
• Needed more auto mode testing beforehand
• Contrary to calculations, mast had large deflections
• The boat could use selectable size rigs

The Ugly

• Could use a nicer paint job
• More ducks

Acknowledgements

• Thanks to Dr. Gordon Stewart for proposing and advising the Sailbot project
• Thank you to the School of Engineering, Computing and Construction Management (SECCM), and the Roger Williams Provost for helping fund the project
• Thanks to Kevin Ulmer for the guidance and $1000 dollar donation that we can use next year
• Thank you to WPI for the donation the boat hull
• Thank you to Kevin Ulmer, Caylin Schnoor, George Higham and Cary Kaczowka for your technical expertise and input towards the project

Questions?