4 ms·
Would it be sufficient to just have a cheap BLE pressure sensor that you could place underneath a potted plant and look for cyclical variations of pressure to d
by 01100011 4y ago
Would it be sufficient to just have a cheap BLE pressure sensor that you could place underneath a potted plant and look for cyclical variations of pressure to determine when to water? I would think that any sensor in contact with the soil is going to have a much shorter lifespan than one which is kept dry and in a less reactive environment.
- solatic 4y agoExcess water drains out the bottom of potted plants. You'd need a coffee-scale style (e.g. Acaia Pearl) sensor, where the electronics are shielded from water from above. Those aren't cheap.
- joshvm 4y agoYou could put this below a saucer/pot stand which is fine for most houseplants. For outdoor projects it's going to have to be waterproof anyway.
- woutgaze 4y agoWhat if the plant grows?
- stavros 4y agoYou can probably fairly easily average out the low-frequency pressure changes. Trivially, you can consider the minimum weight per week the weight of the plant, and calculate the difference based on that.
- Jedd 4y agoYeah, this is my thinking, though I haven't built a proof of concept yet. Load Cell Weight Pressure Sensors are AUD$5 or so, and I reason a shallow receptacle of sand sitting outdoors, where rain can fall in, and direct sunlight can slowly evaporate the water, should provide a sufficiently accurate analogue for soil moisture. Certainly I would expect it would be easy enough to calibrate, using different depths of the medium, different types of medium (coir, perhaps), etc. An upside-down plastic pot saucer sitting under the tray would provide sufficient water-proofing for the pressure sensor, I'd expect.