Web site created by Donato Borello, Amsal Karic, and Randal C. Nelson



-Further Work-

Though a functional artifact was constructed by the end of the semester, we had a number of other ideas that would be interesting to explore given additional time.

Electronic System

The electronic system used a solar motor circuit to flash an LED every few seconds. While this design was minimalistic, it allowed for effective use of the power provided, and when it comes to longevity of systems, simplicity is preferred. However, it would have been more interesting to incorporate a photo resistor sound system which was part of the initial idea. This design was scrapped was due to the approximately 5mA current consumption by the 556 (dual 555) timer IC. Given a bit more time, a circuit similar to the 1381 IC solar engine design could be used to power the sound circuit once a certain voltage threshold is reached. It would then provide continuous power for the sound circuit until a lower voltage is achieved (lasting approximately 10mins), after which the power would return only to the LED system.

Power System

The power system currently uses a 1F ultracapacitor for storage of energy. According to datasheets, it has a very long lifespan and is capable of being charged hundreds of thousands of times. However, the capacitor is hampered by the fact that it has a considerable voltage leakage even when it is in the resting state. Measurements indicate that this leakage is bad enough to drop the voltage to the LED circuit to unusable levels after about 20 hours. Fortunately this is longer than there is night outside (assuming no ambient light) and still allows for the system to work continuously. Better capacitors may be available that have lower leakage, which is primarily due to the need to balance the series string and protect against accumulating an overload in a single element over the course of multiple charge and discharge cycles. The current capacitors use and active system, but it might be possible to design one with even lower current requirements.

Housing System

The final housing structure was fabricated from aluminum-bronze and has all of the necessary windows for the other parts to function properly. Physically it is a durable shell which could take a considerable amount of wear and tear and should be able to last a thousand years without issues. However, the size specification requires it to be approximately pocket-sized and the current design weighs fairly heavily in a standard pocket. The size was necessary to provide the space necessary for the solar cell windows, and the volume required for the loupe magnifier and print image. It might be possible to reduce the volume, especially if some more compact form of information treasure can be devised. The artifact is also a bit blocky-looking, and perhaps not as asthetic as it might be. Future work could refine the shape or add elements to give a more visually striking "steam punk" look.

Treasure

The treasure consisted of a durable sheet of plastic-based "paper" with a fractional millimeter sized font containing the final circuit schematic and a brief attribution for the artifact. Future work could potentially make use of a smaller printing system with stronger magnification which would make it easier to shrink down the entire aluminum-copper alloy case. Additionally, the treasure could make use of a better data preservation system than using a standard laser printer. There are better quality printing materials and methods out there, and it would be nice to get access to use them.