Long time viewers will remember when this idea was conceived two Novembers ago, but essentially it’s a way to detect the relative moisture of a substance.

The principal is the same as in the above post, but this time, I made it bigger and attached it to a Raspberry Pi. The reason this is essential, is because I recently purchased a 12v DC pump capable of moving water. I will be able to sense the relative moisture in the plant, and then the plant will be able to water “itself”.

That will be done in python with the same basic technique I’ve been using all along, but in addition to gathering data about the plant every hour or so, it will be able to see if the plant needs water (by checking hopefully an array of moisture sensors) and then turning on the pump and watering it. I will also eventually integrate twitter and a webcam, but those cosmetic editions come once I know the system works.

To test it, I’ve added another set of data to the graph as seen in the last post and created a testing environment in my windowsill.

Basically I’ve put some dirt and 100mL of water into a container and inserted the sensor and am monitoring the moisture level over the next n hours, here are some pictures:

And here is a graph of some of the data:

I will make another post later today illustrating the process of plating the seeds.