DarkStar Catapult

Michael WhiteheadVince Wong

DarkStar Catapult

ENGR 5November 19, 2002

Overview

Introduction Constraints Project Objectives Approach

Preliminary Ideas Refinement Implementation Construction & Testing Final Mechanism

Results & Possible Improvements Conclusions Acknowledgements

Introduction

Design of a method to carry a standard Food Aid Package down and inclined ramp trigger upon impact of barrier launch over wall 6’2” tall and land 10 linear feet past barrier

PYTHON-INFESTED JUNGLE BOUNDARY

4 in

4 ft 8 ft

STARTLINE

FAP TARGET SPOT6 ft 2 in

3.5 ft

10 ft 10 ft

Constraints

Dimensions cannot exceed 18”x18”x18”

No pre-constructed devices

No motors or propellants

Total cost $20 or less

Cannot exceed 10 pounds

Objectives

To traverse 7 feet down an inclined launching ramp

Successfully launch a Food Aid Package (FAD) of dimensions 4-3/8” x 4-3/8” x 5-1/2“ weighting 7 ounces over a 6’ 2” wall to a spot 10 feet away from the base of the launching ramp.

Approach

Preliminary Ideas

spring launch powerful version

Approach

Preliminary Ideas

crossbow early form of final design

Approach

Refinement-

Most practical designs, but spring or tubing

Approach

Implementation

trigger

stop bars

originally usingwheels

Approach

Construction and Testing

3/4”x3/4” pieces of wood

surgical tubing for propulsion

movable stainless steel rods for trajectory adjustment

hinge and ram rod trigger design

no wheels

Approach

Final Mechanism Design

Results & Possible Improvements

Results The FAD successfully crossed the barrier and landed in

the desired area during testing, but not during actual competition

20th place, 2 failed, 3rd 9.33’, 3 lbs

Possible Improvements Devise system to keep surgical tubing on the device

permanently

Stronger surgical tubing to prevent stretching

Conclusions

Pilot holes are a necessity

Importance of adjustability

Acknowledgements

Michael’s Father Mark Provided valuable insight in building techniques Provided assistance during more difficult construction

periods