Research & Learning
Other Class pages
Before beginning a data logging project it's important to ask a few simple questions about the nature of thing you are logging. Here are a few sample questions:
Once you have a sense of the behavior of the thing your are logging, figure out what you want to use the data for:
The final major issue to consider is how/where you are storing the data and how you want to be able to access it:
That last point is important. If you are taking a reading once a second and that reading has a time stamp and value you might be looking at 100 bytes per reading, which means that in 1 day you'll have generated: 100bytes *60sec * 60 min * 24 hours = about 8.5 megabytes of data.
You may not have the space for that, or depending on what the data you are looking for you might not have to store every reading.
For example if you are trying to track when lights go off or on in a room with a photosensor, you can design your system so that it only posts a reading when it notices a big change (up or down) from the previous reading. Even if this system were sampling every tenth of second, you would generate only a small but relevant set of data.
The overall point is to think about the nature of what you are tracking, what you want to do with that datastream and how much space and computing power you have.