DIY Contactless Sanitizer Dispenser
A lockdown build: reusing an old RO water cabinet and its solenoid valve, an Arduino Nano, and an ultrasonic sensor to dispense sanitizer touch-free without false triggers.
All tags / Electronics
A lockdown build: reusing an old RO water cabinet and its solenoid valve, an Arduino Nano, and an ultrasonic sensor to dispense sanitizer touch-free without false triggers.
Inter-Integrated Circuit (I2C): how the master/slave two-wire bus works, where it is used, and a simple Arduino example for reading a sensor over I2C.
How a two-axis analog joystick works: two potentiometers for X and Y plus a push switch, its pinout, and where joysticks are used from games to surgical robots.
A 4x4x4 LED cube driven by an Arduino UNO and 64 LEDs, with the layer-and-column multiplexing code that animates it.
The MPU6050 motion sensor: a 3-axis accelerometer plus a 3-axis gyroscope with an onboard Digital Motion Processor. What it measures, where it is used, and an Arduino example to read it over I2C.
A from-scratch build log of a man-packable surveillance quadcopter on a Pixhawk flight controller, including every part, why it was chosen, and the trial and error that got it flying.
Serial Peripheral Interface (SPI): the four wires (MOSI, MISO, SCK, CS), how a transaction works, its pros and cons versus I2C, and a simple Arduino example.
How ultrasonic sensors measure distance with sound, the parts of the common HC-SR04 module, and an Arduino example that classifies an object as Near, Far, or Too Far.