Problem Statement
For this project we need a system that is:
- lightweight
- not too expensive
- able to withstand severe vibration
Solutions
Most computers today use hard drives that are not very tolerant of extreme vibration. There are two basic solutions to this problem: either running our system off of a flash drive or running our system entirely off of RAM.
Flash memory can interface to a computer through a variety of mediums including USB keys, compact flash cards, SD cards, etc. There are two basic drawbacks to using flash memory: price and overuse. Flash memory is not cheap compared to IDE drives. Also after a certain number of write cycles (100k - 300k) the memory on these devices begins to wear out and the memory on overused sectors may become unwritable. Despite these concerns flash memory is the only type of long-term memory currently available that is capable of withstanding severe vibration.
Possibly another alternative is to use an operating system that runs entirely off of RAM. In this scenario a hard drive would be connected to our computer only for development. When running our system the hard drive would be disconnected and the system would only be run from RAM. The only drawback to this method is that it would not be possible to log data on the host computer when we are out of network range with the helicopter.
There are many Linux distributions out there that require a small footprint and can be booted from some type of Flash memory. A good comparison of live distros can be found here.
