DarkStar Catapult Michael Whitehead Vince Wong DarkStar Catapult ENGR 5 November 19, 2002

Overview t Introduction t Constraints t Project Objectives t Approach u Preliminary Ideas u Refinement u Implementation u Construction & Testing u Final Mechanism t Results & Possible Improvements t Conclusions t Acknowledgements

Introduction t Design of a method to carry a standard Food Aid Package u down and inclined ramp u trigger upon impact of barrier u launch over wall 6’2” tall and land 10 linear feet past barrier PYTHON-INFESTED JUNGLE BOUNDARY 4 in 4 ft 8 ft START LINE FAP TARGET SPOT 6 ft 2 in 3.5 ft 10 ft

Constraints t Dimensions cannot exceed 18”x18”x18” t No pre-constructed devices t No motors or propellants t Total cost $20 or less t Cannot exceed 10 pounds

Objectives t To traverse 7 feet down an inclined launching ramp t 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 t Preliminary Ideas spring launchpowerful version

Approach t Preliminary Ideas crossbow early form of final design

Approach t Refinement- Most practical designs, but spring or tubing

Approach t Implementation u trigger u stop bars u originally using wheels

Approach t Construction and Testing u 3/4”x3/4” pieces of wood u surgical tubing for propulsion u movable stainless steel rods for trajectory adjustment u hinge and ram rod trigger design u no wheels

Approach t Final Mechanism Design

Results & Possible Improvements t Results u The FAD successfully crossed the barrier and landed in the desired area during testing, but not during actual competition u 20th place, 2 failed, 3rd 9.33’, 3 lbs t Possible Improvements u Devise system to keep surgical tubing on the device permanently u Stronger surgical tubing to prevent stretching

Conclusions t Pilot holes are a necessity t Importance of adjustability

Acknowledgements t Michael’s Father Mark u Provided valuable insight in building techniques u Provided assistance during more difficult construction periods