9 ms·
A Bluetooth Low Energy soil moisture sensor
- larsrc 4y agoVery roughly, how much would the combined parts for these cost, for, say, 10 or 100? How much extra would mentioned DMT assembly be?
- _spduchamp 4y agoNice! Capacitance moisture sensor is totally the way to go. I've never ordered up a custom board with all the little SMD stuff. If anyone is making a big batch of these I'd love to find a way to piggyback on that order.
- mattwdelong 4y agoChiming in to day I would also participate in this order. I have a farm and would love to automate aspects of my irrigation and have been looking for something like this. This in combination with soil temperature would be very beneficial.
- godelski 4y agoOften these moisture sensors (and other sensors here) can have high rates of error. Just something to keep in mind if you use it in a professional setting. But if they are cheap enough you can probably normalize out the variance and get a better reading.
- iancmceachern 4y agoOne of these might work for you: https://m.fr.aliexpress.com/item/32689223035.html?html=static&gatewayAdapt=glo2fra https://m.fr.aliexpress.com/item/32689223035.html?html=stati... https://www.amazon.fr/Corrosion-Resistant-Capacitive-Moisture-Voltage/dp/B07SBQL5F8 https://www.amazon.fr/Corrosion-Resistant-Capacitive-Moistur... If not I run www.openagriculturesupply.com amd would love to help find something that does.
- greggsy 4y agoI have a couple of these hooked into an rpi zero to monitor soil moisture under my house. They work, but wireless would be much better.
- iancmceachern 4y agoI should have linked these for you in the first place. They have a whole ecosystem of sensors that are all wireless. https://www.seeedstudio.com/SenseCAP-S2105-LoRaWAN-Soil-Temperature-Moisture-and-EC-Sensor-p-5358.html?queryID=4791913b1b79d74e445f9c60a3e98084&objectID=5358&indexName=bazaar_retailer_products https://www.seeedstudio.com/SenseCAP-S2105-LoRaWAN-Soil-Temp...
- spelunker 4y agoI just want some for my garden lol
- baremetal 4y agoI would also like to be apart of the order. Automating my farm is high on my list of priorities.
- jomoho 4y agoWould you be interested in letting me ask you a few questions about what you would be looking for when automating your farm? I am working on an early stage startup on the topic please contact me at https://uverd.co/contact.html https://uverd.co/contact.html or leave a comment here. Thanks
- an_aparallel 4y agoif your comfortable with soldering SMD - i have ordered PCBs from https://oshpark.com/ https://oshpark.com/ they offer free shipping from memory - really cheap. i got these shipped from America to Australia :) for 1 design - you get 3 pcbs (identical)
- morphle 4y agoI am ordering 10000 capacitive moisture and temperature sensor boards with an microcontroller wired to 100 wifi and bluetooth gateways including labour and programming for around $5 or €5 per sensor. Most of the cost per sensor is labour so could be omitted. If you want to piggyback onto this order or collaborate please send an email to morphle at ziggo dot nl. We can lower the price per moisture sensor down to $1.42 when we order 100000 or more or by dropping labour intensive features. At a shared/combined batch order of 1 million sensors we will drop to $0.30 per sensor. At this point it is economical to have a sensor per plant (or mecanically planted seed). With optional starlink and solar panels and batteries for full offgrid operation. Custom software features in an app for smartphone or laptop with a https://microblocks.fun https://microblocks.fun type programmability and spreadsheet graphs and website output would be optional. We could add microphones and motion sensors to sense rodents or snails or monitor (rain)forest for illegal cutting with chainsaws or poachers.
- colordrops 4y agoIs BLE kind of turning into the open source alternative to ZigBee/zwave?
- tiagod 4y agoI think it is, LoRa is used a lot for longer range stuff but it's not so open
- auxym 4y agoThe zigbee spec is freely available, I fail to see how BLE would be any more "open source". I think it's just that every smartphone, tablet, laptop, etc now has BLE integrated, so it's easy to make a widget like a soil moisture sensor and connect it to your phone. Also, the newer LE version of bluetooth is quite power efficient so it can run for a while on a CR2032 if you take care to put the MCU in sleep mode between measurements, and whatnot.
- comice 4y agoObviously almost everyone has a device to receive BLE whereas zigbee is a bit more specialist. I've been playing with some arduino hardware that supports zigbee as well as BLE, and BLE is trivially easy to get working where the zigbee stack is much more complicated and much less documentation. So I would guess that plays a part too.
- tiagod 4y agoThis is cool. wonder if conformal coating over this would be enough to survive the outdoors
- ortusdux 4y agoI'm wondering about the longevity of the soil contacting elements. The usual generic soil moisture probes typically have a high failure rate, IIRC due to galvanic corrosion. https://www.digikey.com/en/products/detail/seeed-technology-co.,-ltd/101020008/5482619 https://www.digikey.com/en/products/detail/seeed-technology-...
- _spduchamp 4y agoIt is my understanding that capacitive moister sensors don't have this problem. Can anyone confirm?
- simonrobb 4y agoThat's correct in my experience. Galvanic corrosion was never a problem for the capacitive sensors I developed a few years back (unlike the resistive sensors linked by the parent). However you typically want them more rugged than a bare PCB for industrial settings and since the capacitive field can pass through plastic I had them in a plastic housing filled with resin. Perfectly isolated from the outside environment and hard as a rock. Here's a prototype: https://imgur.com/9yO28CY https://imgur.com/9yO28CY
- metaphor 4y agoI can see how your prototype defends against corrosion, not so much this b-parasite toy. What I don't see anyone talking about is the impact of dielectric moisture absorption[1], which is typically around 0.3-0.5% over 24 hours exposure for cheaper FR-4 on the market, let alone how this product intends to maintain sensor calibration over time. I'd expect to see external corrosion impact at the solder joints first, especially around the battery terminals, but corrosion creep may happen alot sooner than that: vias in the b-parasite prototype are clearly tented[2], but that masking is superficial and won't protect against hygroscopic exposure from the inside; being open source certainly doesn't preclude hobbyists from making even worse material decisions either. [1] https://www.ipc.org/sites/default/files/test_methods_docs/2.6.2.1a.pdf https://www.ipc.org/sites/default/files/test_methods_docs/2.... [2] https://github.com/rbaron/b-parasite/blob/main/img/resized/img1.jpg https://github.com/rbaron/b-parasite/blob/main/img/resized/i...
- WaitWaitWha 4y agoWrite a Home Assistant [0] integration and suddenly you will gain a large set of followers who will also get it into the other closed systems. [0] https://www.home-assistant.io https://www.home-assistant.io
- dexterdog 4y agoIt's already supported as a blemonitor device
- enlightens 4y agoIn fact it does work with Home Assistant (which is a fantastic platform) : https://github.com/rbaron/b-parasite#home-assistant https://github.com/rbaron/b-parasite#home-assistant
- too_big_to_fail 4y agoCurious what “other closed systems” means. I’ve used OpenHAB but is home assistant not open source? I haven’t used it yet.
- WaitWaitWha 4y agoI meant that if you get it working in Home Assistant (FOSS) then the path to Amazon, Google, Apple (closed systems) is easier.
- jdswain 4y agoDoes anyone know what kind of range you get with BTLE sensors like this? I'd think a decent distance would be required in most cases, and BTLE is meant to be short range. A while back I built a LoRa device and we got really good range, 10km at least without having to try too hard, the plan was to deploy 100's of these so it was complicated ensuring communications without collisions, and also this was for a controller not a sensor, which is much harder on the battery as the device needs to listen periodically for updates.
- poink 4y agoTens of meters, highly variable in range and speed, not super reliable.
- arcticbull 4y agoBLE 5.2 has a range of up to 240m. It'll depend on antenna design and ambient conditions but 100m should be easy.
- sgt 4y agoWiFi will do 50 meters, but depending on layout and obstacles, you could be looking at 20. Might be the same for BLE?
- arcticbull 4y ago5.2 in particular extended the range significantly. You're right, I'm confident layout and obstacles will reduce the range.
- defrost 4y agoThat was my first question also - mention in replies are 100-240 m rages which is useful to know. FWiW here in W.Australia 4,000 acres is a mean size for farms (with a skew distribution) .. roughly 4 km a side for a square boundary. I can see these being useful for occassional monitoring around a central solar powered collector - with stakes and flags on the sensors tags so they can be picked up again and recovered as wheat grows. These are the practical issues of modern grain farming (and many farms are much much larger - the mean is skewed by many small plot farms while the bulk of the industry revolves around a few hundred much much larger concerns).
- nathan_f77 4y agoThis is really cool! I'm already running Home Assistant and have bluetooth temp/humidity sensors around the house, so it would be great to add some of these. I've never ordered a PCB like this before with SMT assembly. I have some other PCBs that I would like to design and manufacture, so it will be helpful to start with this and learn how to do it.
- ctoth 4y agoEcowitt make a range of low-cost sensors which all transmit to a central hub over 433/915MHz. They have around 400 feet of range, and it is easy to get the base station to constantly ping a URL with current sensor values. The soil moisture sensor is available on Amazon or directly from Ecowitt[0]. There is also a HomeAssistant integration[1]. [0]: https://www.ecowitt.com/shop/goodsDetail/19 https://www.ecowitt.com/shop/goodsDetail/19 [1]: https://github.com/garbled1/homeassistant_ecowitt https://github.com/garbled1/homeassistant_ecowitt
- TaylorAlexander 4y agoQuestion: Any suggestions on some easy ways to make a web page which displays a status value, where the status is updated by a simple shell command? You mention pinging a URL with sensor values, which seems similar to what I want to do (which is to see if a remote location has power and internet connectivity or not, so I don't bother driving to work if the power is out).
- Donckele 4y agoIf the script is local to the web server then it can be run via cron to produce html/js/css files. If the script is external then it must be capable of making a http request to the server where a script does something similar to the scenario above.
- TaylorAlexander 4y agoYeah. I have a couple servers I could maybe run something on. I guess I don’t really know how to serve a link where I could make an HTTP request. I run servers with discourse and other applications but I never manually serve something. I suppose this is simple enough and I should look that up. What is it called on the server side when you make a URL available for receiving HTTP requests? I realize I’m not sure what to research exactly. EDIT: wait a minute, actually I’ve used flask before with python. I guess I just need to figure out how to run flask on my web server, maybe on a sub domain, without interfering with the discourse instance that’s already there. Hmmm.
- Jayakumark 4y agoCapacitive sensors are better https://www.youtube.com/watch?v=udmJyncDvw0 https://www.youtube.com/watch?v=udmJyncDvw0 This guys tests a bunch and found most of them shipping from aliexpress were bad.. https://www.youtube.com/watch?v=IGP38bz-K48 https://www.youtube.com/watch?v=IGP38bz-K48
- 01100011 4y agoWould 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.
- vmcmkg 4y ago
- franciscop 4y agoI guess no from following the wiki, but is there a way to just buy these modules without any hardware assembly required? I'm interested in hackishly monitoring the soil moisture and this seems great, but not so much into PCB fabrication etc.
- lathiat 4y agoPerhaps the sonoff MS01 is for you. Needs to be paired with a device to plug it into: https://sonoff.tech/product/accessories/ms01/ https://sonoff.tech/product/accessories/ms01/
- LeanderK 4y agoI was recently thinking about a similar hardware (although I have no hardware background). I have a lot of plants, some shared with my roommates, and many frequently die. Taking care of plants together is hard and sometimes we are all away for a few weeks so somebody else is taking care. I would love to have an app that alerts me if something basic is wrong, for which 90% of the time would be too much or not enough water. But what I would need is a cheap plant sensor, I would need like 10 or 15, I don't want to spend more than a few bucks per plant. I didn't find an available solution! I've found a few sensors but they were way to expensive. I know quite a few struggling with plants, having great plans but then killing most so I think quite a few would be interested. I don't know whether the sensors are too expensive or what's the problem. This looks like the right idea, a dumb sensor that could be paired with a inexpensive hub plugged in somewhere talking to some server that distributed notifications and statistics to an app.
- adrian_b 4y agoA few decades ago, I have made an automatic watering system for the plants from the balcony of my apartment, which has worked many years without problems. The cost for the electronic parts was negligible, but assembling the device required some work (mostly for the water pipes, which had to be cut and bent at the right sizes, and then they had to be fixed on some walls). Water was brought through a pipe from the bathroom (from the water reservoir of the toilet, which was mounted at a greater height than the plants, so the water flowed naturally towards them; as an alternative one can add a manifold on an input pipe with cold water, to provide an extra branch for the water, in which case there should be enough pressure to reach greater heights), it passed through an electrovalve recovered from a washing machine, and it was distributed through some thin pipes to the plants. The humidity sensor was printed on a PCB and the electronic part consisted of an operational amplifier, a transistor and a relay that actuated the electrovalve, to turn on and off the water going to the plants. The operational amplifier (a model with high impedance inputs) was connected as a Schmitt trigger with the inputs to a resistor bridge that included the humidity sensor and there were 2 adjustable resistors used to modify the thresholds of the Schmitt trigger, for controlling the humidity levels at which the water was turned on and off. The schematics was adapted from one published in some hobby electronics magazine, so I assume that a search through old collections of such magazines would find many examples. I have used a single humidity sensor and a single electrovalve, common for all, because there was never a significant difference between the humidity levels at different plants. When this is not true, a separate electrovalve can be inserted on each branch of the pipes, with a separate humidity sensor. For the humidity sensor, it may be a good idea to reuse some old PCBs with edge connectors whose contacts are gold-plated, e.g. the PCBs of some old memory modules (after cutting the PCB part with the memory chips and soldering a wire across all contacts). Using the gold-plated contacts for soil contact avoids the oxidation problems that would appear in unprotected copper.
- throwaway894345 4y agoCool to see this on the front page. I stumbled across this a few months ago when looking to make something similar (I have done relatively little embedded programming and was interested in a hobby experiment). I would really like to understand how to design circuits and send them off to be manufactured (especially for something like a soil moisture sensor, which presumably needs the circuit bit to be water proofed).
- creativenolo 4y agoWould be great if this could be solar powered. Something makes me feel uneasy about using batteries to keep plants alive (probably unjust compared to solar production cost over only a few years of use.)
- ortusdux 4y agoI would love a POE variation of this. I'm getting ready to start trenching for pop-up sprinklers and I am going to use the opportunity to run some ethernet lines out for cameras & sensors. It would be awesome to burry maintenance free moisture sensors in the process.
- netsectoday 4y agoAll soil moisture sensors will eventually become uncalibrated, wear out, or fail. The only automation you need to keep a plant alive is a timer attached to a water source. Also, don't forget to feed it with nutrients every month or so... they don't eat soil and letting a plant starve isn't proof you needed a moisture sensor.
- dml2135 4y agoVery cool, I bookmarked this to come back to later. As a gardener who recently built a home server, I hope to eventually set up a soil moisture monitoring system, which I could then in turn eventually hook up to an automatic watering system. My rough idea of how this would work would be a bunch of sensors that I then hook up to something like influxDB/grafana. If anyone has built such a system themselves I'd love to know how you did it.