The Solutions

Alternate Solutions:
Every individual aquatic challenge necessitates the design and construction of a unit capable of performing the given task. Below four different variations of the units designed to complete each challenge.

Challenge 1: Placing a ping-pong ball through a hoop

1. Catapult- The catapult will use a tension release arm pre-loaded manually. A 3-wire servo will release the arm using a standard drive shaft to straight gear system. The arm itself will be constructed from the booster kit with a plastic cup fixed to the end. A structure in front of the arm will limit its range of motion to 70 degrees, also causing the arm to return back to the resting position after firing.                 
2. Slingshot- The slingshot will consist of two upright structures mounted directly to the hull. Connecting them near their apex will be an elastic string. When pulled back this string will be loaded onto the same mechanism used on the catapult design. A servo will release the tension in the elastic firing the projectile.                                                    
3. Pinball- The pinball mechanism will work like the firing mechanism in a pinball machine. A spring will be attached to a contact surface. This system will be placed into a tube with a release mechanism powered by a 3-wire servo. Once released, the contact surface will strike the projectile and fire it down an exposed pathway approximately 8 inches long. 
4. Telescoping claw- The claw will hold the projectile until it is ready to be released. This action will be controlled by a 3-wire servo. The arm to which the claw is attached will extend under the power of a 269 motor. The drive shaft will rotate a gear which will have contact with fixed gears along the arm.                                                       

Challenge 2: Towing a Stranded Vessel

1. Hook- The hook will be a single jointed with a 3-Wire servo at the base where it is mounted to the hull. The arm of the hook will extend approximately 12 inches with a 3 inch offshoot connected perpendicularly downward at the end. This offshoot will have an adhesive contact surface on its inner side to grip the inside of the hull of the stranded vessel. 
2. Magnets- The magnet solution will simply be an electromagnet mounted to the hull of the vessel. A 3-wire servo will control the circuit from the auxiliary battery in order to shut the magnet off when the stranded vessel needs to be released, and before the vessel needs to be towed. A piece of magnetic material must be mounted on the stranded vessel prior to the rescue attempt.                          
3. Telescoping rod- On the end of an arm an adhesive contact pad will be applied. The arm will be approximately 12 inches long, and controlled by one 269 motor. A gear on the end of the motor drive shaft will rotate and move the fixed teeth on the arm. When retracting, two upright structures will be mounted directly to the hull of the vessel. The arm will be able to retract past these two structures but the vessel being towed will be disconnected.                                                                                   
4. Pincers- There will be one fixed arm with a contact pad on the inner surface. The other arm will be fixed onto a structure running perpendicular to the arms. The mobile arm will move horizontally across this structure under the power of one 269 motor. The gear ratio will be adjusted to ensure slow but steady movement on the arm.                        

Challenge 3: Sinking an Enemy Vessel

1. Downward hook- The hook will be mounted onto the vessel and pivot from the hull of the vessel. The rotation will be downward 110 degrees in an attempt to capsize the vessel. This motion will be controlled by one 3-wire servo. The arm will be approximately 12 inches long and be constructed form the booster kit.                                                 
2. Hole puncher- The hole puncher will be a weighted rod approximately 0.5" in diameter. This rod will be housed inside of a tube with a loaded spring behind it. The spring tension will be release by the operation of a 3-wire servo controlled gear slide system, similar to the one used in the pinball solution for challenge 1.                                                   
3. Upward hook- The hook will be mounded onto the side of the vessel. It will dip into the water prior to its operation and them rotated upward under the power of a 3-wire servo in an attempt to capsize the enemy vessel. The servo will be at the base of the hook, where it mounts to the hull. The arm will be approximately 12 inches long.                          
4. Splitter- The splitter will be single jointed mounted at the hull. Two upward struts and an elastic band will provide tension for the splitter to release upward and down in a full 180 degree arc. A 3-wire servo tension release mechanism similar to the hole puncher's mechanism will release the arm of the splitter. The arm will be approximately 12 inches long and have a weighted blade at the end. The blade will attempt to split the enemy vessel, destroying it.                    

Challenge 4: Floating a Buoy

1. Magnet- The magnet releasing system will will operated based on a connection controlled by a 3-wire servo between an electromagnet and its ancillary battery. The magnet will attract an opposing magnet on the buoy itself. When the connection is broken the buoy will drop off the side of the vessel.                                                                  
2. Rotating claw- The claw will be mounted on an arm approximately 4 inches long. The arm will be mounted directly to the deck of the vessel and rotate under the power of a 3-wire servo. The claw action itself will be under the power of an additional 3-wire servo. When the claw releases, the buoy will be dropped into the water. The arm can then rescind the claw back to its place above the vessel. 
3. Slide- The buoy will be placed before the mission at the end of a platform approximately 8" long and 4" wide. One 269 motor with a gear and drive shaft will move a piling up and raise the side of the platform with the buoy. The piling will extend to approximately 6". The buoy will then slide down the platform and into the water. The 269 motor will reverse, and return the piling, leveling the platform.                      
4. Cutting a tow string- The buoy will be towed behind the vessel for the entire mission until the time to float it comes. At this time, a 3-wire servo will rotate a drive shaft with one 1" gear on the end. This will turn another, smaller gear next to it, which is attached to the action of a pair of scissors. These scissors will cut the string, releasing the buoy.