With the current coronavirus situation, we’ve been encouraged to wash our hands regularly for 20 seconds – or approximately how long it takes you to hum “Happy Birthday” from beginning to end twice. That sounds easy enough, but do you really do this every time? What you need is some sort of automatic timer, perhaps with a dial gauge for easy visual reference.
As it just so happens, Gautam Bose and Lucas Ochoa built such a device with an Arduino Uno. The aptly named Wash-A-Lot-Bot detects a person’s hands in front of it via an ultrasonic sensor, then ticks a dial timer from 0 to 20 (or rather 20 to DONE!) using a micro servo.
This simple setup can be made with little more than scissors and tape, making it a great way to learn about Arduino and programming while you’re stuck indoors.
Whether it’s with an old friend or new acquaintance, we’ve all had those awkward gaps in conversation. Do you speak next, or let the other person lead the discussion? If that’s not happening naturally, then SASSIE, or “System for Awkward Silence Solution and Interaction Enhancer,” is here to help.
The cylindrical device detects audio feedback via a pair of microphones positioned near each person in a conversation. When a sufficient silence is detected, SASSIE pops a flag out and rotates to indicate who needs to talk. If that wasn’t enough of a hint, it also audibly tells that person to say something.
SASSIE is powered by dual Arduino Uno boards, one of which takes care of the bulk of the control functions, while the other actuates the stepper to spin the top indicator.
What does one do with over 1,000 LEDs, white acrylic, and 288 IR sensors? If you’re Redditor “jordy_essen,” you create an interactive light panel.
In one mode, the user pull a reflective tool across the sensors to draw a paths, with potentiometers implemented to select the color. It can also be set up to play a sort of whack-a-mole game, where one has to activate the sensor in the same area where it illuminates.
For this amazing device, jordy_essen uses not one, or even two, but six Arduino Mega boards to drive the LEDs directly — in turn controlled by a webpage running on a Raspberry Pi. If that wasn’t enough hardware, an Uno is tasked with taking inputs from the color potentiometers.
Loop antennas for ham radios use heavy duty variable capacitors for tuning. Since such capacitors need to be physically turned for adjustment, radio enthusiast Jose B.O. made his own remote rig using an Arduino Uno and CNC shield.
The CNC setup allows stepper motors to rotate through a range of angles for frequency selection, and three antennas can be controlled via separate Pololu A4988 driver modules. An optical encoder is used for control, along with buttons for preset frequencies, and a 16×2 I2C LCD display provides visual feedback. Microswitches are implemented to set the upper and lower bounds for the stepper motors.
When you step out in public, you’ll often be filmed by a number of cameras and perhaps even be analyzed by tracking software of some kind. The Watchman robot head by Graham Jessup, however, makes this incredibly obvious as it detects and recognizes facial movements, then causes a pair of eyeballs to follow you around.
The 3D-printed system — which is a modified version of Tjhazi’s Doorman — uses a Raspberry Pi Camera to capture a live video feed, along with a Raspberry Pi Zero and a Google AIY HAT for analysis.
This setup passes info on to an Arduino Uno that actuates the eyeballs via a 16-channel servo shield and a number of servos. The device can follow Jessup up, down, left, and right, making for a very creepy robot indeed!
The build uses the laptop’s Enhanced Dictation functionality to convert text into speech, and when a Python program receives the proper keywords, it sends an “H” character over serial to an Arduino Uno to activate the vehicle.
The Uno uses a transistor to control a 12V relay, which passes current to the Jeep’s starter solenoid. After a short delay, the MacBook then transmits an “L” command to have it release the relay, ready to do the job again when needed!
As a fan of Iron Man, Forsyth channeled his inner Tony Stark and even programmed the system to respond to “JARVIS, let’s get things going!”