Posts with «soil» label

Simulate Climate With An Arduino

There are usually two ways to go about any task: the easy way and the hard way. Sometimes we might not know there are two options, but once we see someone else’s solution we might feel differently. When running a greenhouse or small farm, for example, we might decide to set up dozens of sensors to measure temperature, humidity, soil moisture, dew point, sunlight, or any number of other variables. That’s the hard way. The easy way is to use the Arduino-powered Norman climate simulator from [934Virginia].

Rather than relying on an array of sensors, any of which could fail or provide erroneous data for any number of reasons, Norman relies on a simple input of data about the current location – target coordinates, specified date ranges, and minimum/maximum values for temperature and humidity – in order to learn and predict the weather conditions in that location. It makes extensive use of the Dusk2Dawn library, and models other atmospheric conditions using mathematical modeling methods in order to make relatively accurate estimates of the climate it is installed in. There are some simulations on the project’s Plotly page which show its successes as well.

Presumably anyone using this device could run a greenhouse relatively well on only $10 worth of electronics rather than relying on a suite of sensors and input data, which is helpful for anyone strapped for cash (especially in developing areas of the world). The project is named after Norman Borlaug, a famous soil scientist and someone worth reading about. The first (and possibly only) sensor we might want to add to this project is a soil moisture sensor, since yearly estimates won’t tell us whether it has just rained or not.

Images courtesy of Wikimedia Commons.

Hack a Day 03 Aug 06:00

Sensing Soil Moisture: You’re Doing it Wrong!

If you compulsively search online for inexpensive microcontroller add-ons, you will see soil moisture measurement kits. [aka] built a greenhouse with a host of hacked hardware including lights and automatic watering. What caught our attention among all these was Step 5 in their instructions where [aka] explains why the cheap soil sensing probes aren’t worth their weight in potting soil. Even worse, they may leave vacationers with a mistaken sense of security over their unattended plants.

The sensing stakes, which come with a small amplifier, work splendidly out of the box, but if you recall, passing current through electrodes via moisture is the recipe for electrolysis and that has a pretty profound effect on metal. [Aka] shows us the effects of electrolysis on these probes and mentions that damaged probes will cease to give useful information which could lead to overworked pumps and flooded helpless plants.

There is an easy solution. Graphite probes are inexpensive to make yourself. Simply harvest them from pencils or buy woodless pencils from the art store. Add some wires and hold them with shrink tube, and you have probes which won’t fail you or your plants.

Here’s some garden automation if this only whet your whistle, and here’s a robotic friend who takes care of the weeds for you.

Filed under: green hacks