IMechE Challenge
Teammates:
Lee Bo Ki
Sebastian Chan Yong Jun
Denzel Odia
Adam
Kim Ha Bin
Table of contents

Target

Design

How it works

Calculations

Cost
Content
Target

Shoot a squash ball 6m away from the target with a string attached from the
table.

As accurate as possible

Under £30
Rejected Designs

Nerf Gun – Against the rules

Catapult - Unreliable

Water Gun – Difficult and expensive

Fly wheel -Expensive

Explosives – Against the rules

Slingshot – Not suitable and too simple
Parts

Electric pump with gauge

Valve

PVC Pipes

String
Assembly

Solids works picture

Diff. views
Assembly

A hole is drilled into the electric pump to connect a pressure valve.

The PVC pipe is then connected to the valve.

Super glue is used to connect the components and to ensure no leakage of air
in the system.

The 3m pipe is elevated at an angle of 30° from the base.

The string is attached to the ball and to the bottom of the PVC pipe.

The PVC pipe has a diameter close to the value of the diameter of the ball for
more accuracy.

Styrofoam is used as a base to stabilise the whole system.
How it works

Air is pumped into the system using the electric pump.

The air being stored causes air pressure and is released via a valve.

Speed of the air released causes the ball to move along the PVC tube.

The squash ball will move in a parabolic motion due to gravity.
Calculations

Assumptions made :

Velocity of air pressure leaving the cannon is equal to the velocity of the ball
leaving the cannon.

Air resistance is negligible.

The time to accelerate the ball is 0.005s (Estimated)

The target and the ball is perfectly horizontal and perpendicular.
Cost

Under £30

The rest are used to bribe the judges
Item
Quantity
Cost
Bicycle Pump
1
£14
PVC Pipes
1
£5
String
1
£1
Pressure Valve
1
£4
3D printing
1
£
Styrofoam
1
£2
Super glue
1
£2