Catapult Trajectory Project

Goal: build a catapult precise enough to calculate where shots will land.

Parameters: Launch a golf ball or tennis ball Must launch at least 5.0 m horizontally but not more than 20 m Must launch at least 2.0 m high but not higher than 5.0 m (meeting the minimum ensures the ability to hit the target but going farther reduces the chance of a “bull’s-eye”) Must be small enough to store easily in the room and to be carried by one person

Teams: 1 to 3 people per catapult – NO MORE THAN THREE!!!

Scoring: 40 points

On-time completion of device within parameters: 8 pts Creativity, Aesthetics, Quality of construction: 15 pts Calculations of velocity and target locations: 15 pts (must NEATLY show all work and diagrams) Hitting 2 targets: (3, 2, 1, or 0 each) (6 possible) 2 pts

Safety: Device should not be more powerful than necessary No combustion or CO2 containers Hands away from parts that could catch or injure Use only tools that you and your parents are comfortable with you handling Use your team’s expertise in various construction techniques to reduce the risk of injury

Tips: Springs are more consistent than bungee cords A “stop” can provide a fixed launch angle A well designed cup or carrier can release the ball consistently Tubular guns tend to put spin on the ball PVC pipe is easy to use, but not rigid, and the glue is noxious More powerful is not better. The goal is precision.