Introducing Lambda Nodes wireless sensors

Other Hardware Home Automation
1

Hi

I want to introduce to you a project I have been working on for quite some time that can help you with your home automation project:
Lambda Nodes are small wireless sensors based on NRF24L01 transceiver modules with the goal to be small, low price easy to use and open source. To my knowledge there is no such thing yet: either the sensors are expensive, bulky or closed source.

I noticed that a lot of people are struggling with wiring of their sensors or putting a lot of time and effort into making wireless sensors that are bulky and are complicated to maintain. If you want something that is small, easy to get started with and still have a long battery life then this is for you.

I designed the Lambda Nodes to be more or less 'plug and play'. The software automatically detects the nodes, configures them and either saves the data on an SD card or streams it to a server like thingspeak, a MQTT broker, plot.ly or wherever you want. No more hustle with I2C libraries, wrong readings and messy wires.
Using the custom designed base station called the Alpha node, based on an ESP8266 you can easily configure the nodes with the built in web page but it is also possible to use them with just about any Arduino compatible hardware or even a Raspberry Pi.

The project is in an advanced state, all the hardware is working and the software is almost ready to be released.
Sorry the project is not yet open source, it will be as soon as I get around to actually start crowd-funding for having them manufactured at Seeedstudio.
For that I am hoping to get some feedback from you: please let me know if you would be interested to help funding the manufacturing.

I recently made a simple introduction website on wordpress. So if this sounds interesting please check it out: Lambda Nodes website

Also I recorded a video showing the setup I made for the Zürich Maker Faire and the live data streaming capability:

Demo Video

Here are some specs of the advanced prototypes:

  • Radio frequency: 2.4GHz
  • Transmission range: up to 70m
  • Battery: CR2032
  • Battery life: up to 3 years

Theta Node (Temperature)

  • Size: 43x22x9mm (LxWxH)
  • Accuracy: ±0.5°C
  • Resolution: 0.02°C
  • Sensor: precision NTC
  • Range: -20°C to 80°C (up to 250°C with external NTC)

Epsilon Node (Soil Moisture probe)

  • Size: 100x22x9mm (LxWxH)
  • Resolution: 0.1% (0% is dry, 100% is fully wet)
  • Sensor: capacitive probe

Kappa Node (environment sensor)

  • Size: 43x22x9mm (LxWxH)
  • Sensor: BME280
  • Measures temperature, humidity and pressure

Alpha Node (receiver station)

  • Size: 50x50x12mm (LxWxH)
  • Uses ESP8266 for WiFi
  • SD card for local data-logging
  • Contains configuration web-page
2

Looks great! Nice to see a neat solution.

Some questions;

Hardware, I couldnt see the chip you were using on the nodes, Im assuming its a 328?

Solution, you're getting great life out of the batteries. Im assuming thats just from sleep modes?

Software, is your networking based on tmr24's libs, or something home grown?

3

Thanks for reporting back

scrumfled:
Hardware, I couldnt see the chip you were using on the nodes, Im assuming its a 328?'

Nope, it's a more modern ARM based controller from ST: a STM32F03

scrumfled:
Solution, you're getting great life out of the batteries. Im assuming thats just from sleep modes?

Yes, the STM32 has a great 3uA standby consumption, much better than the ATmega or ATtiny. The wake-up period can be changed during initialization phase (wireless command from base station). I measured 32 days or so for a 1 second wakeup interval but recently found that with a small hardware improvement this may be increased even more.

scrumfled:
Software, is your networking based on tmr24's libs, or something home grown?

I am using a library on the Arduino side but I think it is the one from maniacbug. The network protocol is completely application specific to keep the data to a minimum to maximize range and minimize power consumption. Never heard of tmr24's libs nor did I find anything when googling that.