Examples for obniz devices controlled by Node-RED
This repository contains a growing collection of examples for electronic circuits based on obniz boards and controlled by Node-RED. They are organized around the parts found in the Keyestudio 48 in 1 Sensor Kit in order to help my students to carry out web-based or cloud-connected hardware projects without requiring too much knowledge of electronics.
Please note: this work is currently in progress. While it may already be used, do not expect it to be finished before end of October 2021.
Obniz boards are microcontroller boards based on the ESP-WROOM-32 with an additional OLED display and a three-way switch on-board and additional circuitry to make GPIOs 5V tolerant and robust even against short-circuits.
The boards and their firmware have been designed to be connected to local Wifi networks out-of-the-box and without any need for additional hardware. The devices then connect to a server operated by Obniz and provide a REST interface via which they can be controlled. In contrast to most other microcontroller boards the idea is therefore not to program the controller itself but to get access to its components and I/O pins over the internet.
This approach makes obniz devices unusable without an active internet connection (or while the servers at obniz are down) and cause an extra latency (making them unsuitable for real-time applications), but if the planned project requires internet access anyway, these drawbacks may not weigh so heavy - particularly since, on the other side, the offered hardware is astonishing robust and may therefore also be used by novices in electronics.
Keyestudio offers dozens of different sensors and actors on small boards which may be (plugged into breadboards and) directly connected to a microcontroller - at reasonable prices. Using such modules can speed up hardware development and reduce wiring and soldering efforts.
The 48-in-1 sensor kit contains the following modules:
| white LED | Knock Sensor | analog Gas Sensor | Rotary Encoder |
| RGB LED | digital Tilt Sensor | analog Alcohol Sensor | Relais |
| 3W LED | capacitive Touch Sensor | Steam Sensor | linear Temperature Sensor |
| Traffic Light | Flame Sensor | analog Piezo Vibration Sensor | Temperature and Humidity Sensor |
| active Buzzer | Reed Relais Module | Voltage Sensor | magic Light Cup |
| passive Buzzer | PIR Motion Sensor | Thin-Film Pressure Sensor | Attitude Sensor |
| digital Push Button | analog Temperature Sensor | Ambient Light Sensor | IR Proximity Detection Sensor |
| Collision Sensor | analog Rotation Sensor | UV Sensor | triaxial digital Acceleration Sensor |
| Line Tracking Sensor | Photocell Sensor | digital IR Receiver | 9G Servo |
| IR Obstacle Avoidance Sensor | analog Sound Sensor | digital IR Transmitter | Ultrasonic Sensor |
| Photo Interrupter | Water Sensor | Pulse Rate Monitor | LCD |
| magnetic Hall Sensor | Soil Humidity Sensor | Joystick | I2C 8x8 Dot Matrix LED |
In the end, this repository should contain examples for as many of these sensors as possible.