The Automated Life Preserver Launcher

Curtis Sand & Zach Byrne

Overview

Automatic System for launching life preservers when someone falls off a boat.

In a real system: thermal cameras, an actual pneumatic life preserver launcher, victim would carry a panic beacon

In our system: regular cameras, Nerf launcher, flashlight

Inspiration

Incorporate many interesting subsystems:

Serial Communication

Stepper motor/servo control

Image processing

Binocular range finding

What’s cooler than a Nerf turret?

The ALPL

The ALPL

The ALPL

Finding Bright Spots

Find the average location of bright pixels.

Effective for single light sources.

Fails for images with many lights or high overall brightness.

Calculating Distance

Second camera finds angle θ.

Fixed width w. Limitations:

Camera FoV Image

resolution 57°

Theoretical Range

Min: 0.78 meters

Max: 32.6 meters

Aiming Control range by

adjusting launcher elevation.

Experimentally determined ranges.

Fit a parabola to the data.

Setbacks Mechanical Issues

Moment of Inertia on the elevation motor.

Firing servo missing trigger.

Difficulty squaring cameras

Computer Issues

Instability of external RAM.

Unreliable connection to cameras.

Floating point bugs.

Results

Success!...Mostly.

Finds targets...sometimes.

Calculates distance...reasonably.

Calculates correct elevation...almost.

Acceptable Proximity to target...usually.

Questions?