New ESP32-based PCB with LoRa support from Christophe

Hello everyone,
I started a year ago to develop a connected hive. The prototype I am currently working on, uses a Lora communication system through the things network to node red and finally the Blynk application

Starting from my prototype, I developped a PCB with Kicad. In this PCB there is a ESP32 module, a RFM 95 lora, Deepsleep mode, load sensor with hx711, BME280 sensor and multiple DS18B20

Next it’s to test the curent consuption during the deep sleep :slight_smile:

christophe

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Nice, I see a solar charger! What model do you use? Do you have the HX711 breakout on the PCB’s other side? The blue screw terminal on the left side is for the DS18B20? Why is it a four screw terminal? DS18B20 has 3 wires, or is it for the load cell?

The solar charger is a TP4056, for the HX711 it’s an other PCB board but for the next version I will make it on the main PCB ( problem is I have different seize of HX711 breakout in stock). For the blue screw terminal block, yes it’s for the DS18B20 but only 3 connections are used for. In my stock I don’t have 3 terminal block connections ;). But I will use this last one for somethink else…

Dear Christophe,

thanks for sharing some details of your system and its design. We would be very happy to support you and your system with our backend components revolving around data visualization within Grafana. Would you be interested to support this within the firmware your are developing as an alternative to the backend-telemetry based on Node-RED / Blynk?

With kind regards,
Andreas,

Dear Andreas,
Yes I will be very interested to be involve on data visualization within Grafana, but I have no idea how it works… I will try to find more infirmation here ;).

Some modification on my PCB I done, I included the HX711 on it, PCB is ordered now I will just wait!:

I would recommend to add a screw terminal for the load cell’s shield. Connecting the shield to ground makes the analog signal less sensitiv for interfering signals. Btw. a similar PCB with an ESP8266 Open Hive WiFi Solar / Adafruit HUZZAH

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Ok many thanks clemens, I will make the modification right now ;)

Dear Christophe,

Nice to hear. Grafana is really the best thing which could have happened to us while starting to build up our infrastructure.

There are many ways you can approach that. The most basic way would be to forward your measurements directly into a timeseries database like InfluxDB using a respective data flow within your current Node-RED setup. There are probably many examples around the net outlining this.

However, no matter if you want to run the whole system on your own premises or if you want others to rebuild and reuse what you are currently doing there, there’s another option most likely called the Hiveeyes Backend. We built this for this very purpose of making it aspiring newcomers to the topic of beehive monitoring easier to get started on the backend side of things.

Some information around it is scattered between the static documentation and the forum. We already have some pointers to start reading about it. Essentially, looking at the documentation of Kotori is not a bad place to start. Specifically we like MQTT, so I am humbly directing you towards Data acquisition over MQTT — Kotori 0.22.7 documentation here. We will sort out more details while we go!

May I also humbly ask you if you plan to publish your design and the firmware using an open source license actually? In that way, it will even be easier for me and others to supply appropriate snippets of code by using regular patches towards it.

Again, I want to emphasize that this kind of integration is not a one-way route: The Hiveeyes Backend can be used by single beekeepers, beekeeper collectives or even larger communities to collect and share their data with each other. While we are running a medium-sized community on https://swarm.hiveeyes.org/ for everone who likes to join us, everything we do is free software and can be reused for any scenario one would like.

So, if you like that, I will be happy to support your endeavor further in that spirit in order to integrate things closer with each other. Saying this, I humbly ask for a bit of patience as I am currently traveling. See you!

With kind regards,
Andreas.

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Please bear with me, I am not a hardware guy at all. However, I would like to mention Stromversorgung HX711 and many other things collected on [INDEX] ADCs für Wägezelle in this context. The HX711 and gettings things right around it is nothing to fuzz with. As I can’t deduce how you have exactly integrated it, I would recommend to ask for review by one or the other experts in this forum.

Otherwise, temperature-related drifts like Ausreißer bei den Temperaturwerten, Drift bei den Gewichtswerten observed by @IngoP might happen in the wild.

Answering more specifically to your statement about placement of the HX711, some of us who take things more seriously even recommend placing the HX711 near to the load cell. @weef, @IngoP or others might want to elaborate on that further.

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Any thanks for your explanation, I will look at the links you give me :). I did already some tests out side with low temperature too…

Hello everyone,

Some update about my project, my PCB is working but I have 2 modifications to do on my new version. Weight, temperature and humidity data are received to TTN. Next is to test the distance of my LoraWan :slight_smile:

Christophe

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The TP4056 is not a dedicated solar charging IC, please search for a more solar-fitting part like the CN3065 (almost pin-compatible). Some people here use this, so we have some discussion coverage about it, too. - Both ICs have setting resistors for charge current; these should be adjusted to fit the solar cell used.

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Many thanks Weef, I will look regarding information for the CN3065 :)

Hello everyone,

I would like to use 2 channels (A and B) on the HX711 but I cannot find an example to read the 2 channels at all. Do you have any examples?
many thanks :slight_smile:
christophe

Dear Christophe,

things like READING BOTH CHANNELS .. solved · Issue #77 · bogde/HX711 · GitHub and using channel A + B together? version 2 · Issue #12 · bogde/HX711 · GitHub are telling us that one would have to invoke

scale.set_gain(128);

for selecting channel A and

scale.set_gain(32);

for selecting channel B.

However, I have not verified that and know nothing about any consequences thereof as I am not a hardware guy at all ;].

Cheers,
Andreas.

Dear Andreas,

Many thanks, ok now I understant better :). I will test it :slight_smile:

Cheers,
christophe

Hello everyone,

I would like to know if you would have a system which would allow to wake up my system with my esp32 which is in sleep profont for example in the event of hive theft? i know i can use gpio to wake up it but i’m not sure which sensor? Do you use in anti-theft systems?

many thanks for your help

christophe

Hello everyone,

Just to share my new version of my PCB with a GPS NEO6 and an accelerometer. The accelerometer will wake up my esp32 if my hive is moved. I need to check what is the sleeping current of the MPU6050 during my ESP32 sleeping time.


Christophe

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