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.
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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.
Building a full electronic drum kit from piezo triggers and a DIY rack, converting strikes to MIDI, and driving the sounds from GarageBand on an iPhone with headphones.
An IoT build that pulls live COVID-19 figures for India from a web API on an ESP8266 and scrolls them across a 64x32 P4 LED matrix using the PxMatrix library.
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 compact, space-saving octopad built from piezo sensors and aluminium-composite triggers, wired into an existing Roland TD-11 module for silent, headphone practice.
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.
Air drums that trigger MIDI notes when your hands pass over infrared sensors, built on an ATmega8 at the MIDI baud rate, with a 555-based 38kHz IR front end and TSOP1738 receivers.