The SPECTRE is the actual hovercraft that drives around and pops enemy balloons
SPECTRE Chassis Mechanical Design
For the mechanical base of the hovercraft, we used 20.5" diameter .125" thick duron. The motor stands and blade protectors were all cut out of duron of the same thickness. The rule with hovercrafts is not always to go as light as possible - when we switched to duron from foamcore, we got better performance. This is because the added weight of the duron disc gave us a much more even distribution of weight, and tiny movements in battery and component location no longer altered the center of gravity as much as they had before.
Hot Wire Balloon Popper Mechanism
Our balloon popper mechanism, made to resemble Magnemite's magnet arm, utilizes a hot wire to pop opponent's balloons. When the "Pop Balloon" command is sent from the controlling MI6, the SPECTRE's microcontroller will turn on a power MOSFET that will drive approximately 1 amp of current through a thin high resistance wire fixed across the "magnet." A servo will rotate the arm down as Magnemite attempts to pop a balloon. After two seconds, the hot wire will turn off and the servo will return the "magnet" to the deactivated state.
Hovercraft Skirt
The skirt is one of the most critical parts of a hovercraft. There are a lot of different variations - hard skirt, soft skirt, material choices for both, etc. We tried about a dozen different variations before we settled on the one pictured below which gave us the best functionality. It is a soft skirt, meaning it is compressible and made of fabric which inflates when the lift fan turns on. The fabric of choice is ripstop nylon, a robust utility fabric that can be easily torn into rectangulars due to the rectangular grid the fabric is created in. Rip of a long rectangle of fabric (~70 inches in our case) and wrap it around a ring of foamcore. Wrap it around a smaller ring of foamcore on the bottom side so the skirt pulls in by a few inches. Take this assembly and attach it to the bottom of your hovercraft and you have a robust hovercraft skirt.
CAD files
spectre.zip | |
File Size: | 4384 kb |
File Type: | zip |
popper_mechanism.zip | |
File Size: | 511 kb |
File Type: | zip |