Update

Today we worked on designing the design of the project.  We brainstormed and made a few sketches on paper.  We kept the design small to minimize the catapult arm weight and to reduce size in general.  We also decided against making the catapult "turnable" or adjustable.  The design would have called for attaching a servo to the bottom of the project and it was decided that it would be difficult to attach the servo without it being weak at the attachment point.  The sketches were then transformed into Solidworks files.  The decision was also made to use the catapult arm as the 3D Printed piece since it needs to be light, strong and exact in order to work properly and all three of these properties are met by using plastic.  We also decided today that the servo will not be fast enough to "throw" objects, therefore we will need to use a DC motor and a motor shield.  The design also includes 3 leds and a button which will be pressed when ready to fire.  The leds will "count off", lighting up the first, second and third ones in order before it fires.