Guest Blog – Smart Garden System 3D Printed Top for Sensors

Guest Blog – Smart Garden System 3D Printed Top for Sensors

Thank you Mark Strait (and son!) for the following Blog about adding a 3D Printed cover to the Capacitive Moisture Sensors used in the Smart Garden System.

What is the Smart Garden System?

The Smart Garden System (or SGS for short) is an introductory, easy to buildSmart Garden System Raspberry Pi based environmental monitoring and plant watering system using advanced sensors to monitor the soil moisture, monitor the sunlight, watch the air quality and monitor temperature and humidity.

You can see the product here.  While this product does not come with a Raspberry Pi, you can buy a fully loaded SD Card with all the Smart Garden System preinstalled here.

 

 

 

 

 

Building the 3D Printed Cover for the SGS Sensors

by Mark Strait

After working flawlessly for 3 weeks, it happened . . .  The reading for the moisture sensor on my Raspberry Pi Smart Garden System went from it’s regular average of around 60% to an anomalous 100%.  Checking the plant did reveal that the soil was in fact very wet. Was the system malfunctioning and overwatering? Nope. A little investigation found that my 10 year old had poured a glass of water over the plant.  Oh well, I thought, as it dries out everything will go back to normal. After a week or two of the reading staying at 100% I began to expect that something more was afoot. The response to my post to the SwitchDoc support boards indicated that the sensor had probably been fried when my son poured the water into the plant.

I ordered a replacement sensor but also set out to figure out a way to keep this from happening again.  Firstly, I spoke to my son about how I’d really appreciate it if he didn’t just randomly pour water over my projects.  My second effort was to create a barrier to better protect the sensor from water that will, by necessity, be proximal to it.  Having received a 3D printer for Christmas, I set to designing a cap to place on top of the sensor. I ended up using Tinkercad to design this piece because it is by far the easiest 3D design platform with a very flat learning curve.  Within a few hours I was able to design and print (using Cura) my first prototype. It was a little too small so I added a couple of mm and tried again. I ended up with a little cap that sits snugly on top of the sensor. To further protect the sensor, I filled the space within the cap with Dielectric Grease.

With everything now in place, I plugged in the sensor and everything went back to working as it should.  Have I tested the cap by pouring water on top of it? No, no I haven’t. But I do feel that the sensor has at least a fighting chance if some random event should befall my Meyer lemon tree again.  I have attached the stl files for this cap just in case, you too, have family members that don’t understand that electronics + water do not always mix.

You can download my STL file here.