Introduction: Quick Quiz: 5 Min No-Solder Cap-Touch Buzzer Game
This gives you the plans for setting up the quickest version of a quiz-show type buzzer system that I have seen. You only need a couple LEDs, some gator clips, and an Arduino, and you will have a buzzer system ready for 4 people in under 5 minutes! It all fits right on a regular board; plug and play! As a bonus, this uses Cap-touch sensing for the buzzer, so you can basically use almost anything as your buzzer, like a coconut or soda can, or even your friend.
Traditional Buzzer Systems
There are plenty of really nice instructables out there for making really high quality buzzer systems such as https://www.instructables.com/id/Quiz-O-Tron-3000-A...
Even though the electronics aren't that complicated for making a basic switch, many still require a couple extra components (like resistors), and additional building steps (like soldering together components). At a minimum you usually need to run two separate wires out to each buzzer, which can be kinda cumbersome with multiple players.
Cap-Touch Buzzer (like Makey Makey!)
Using capacitive touch sensing lets us run just 1 wire out to each buzzer. It also lets you make more fun styles of buzzers! Instead of just a regular button, contestants can use anything that's kind of conductive like a banana, a coconut, a cup of water, a pet tortoise with a piece of copper tape on her, or a piece of metal. Check out Makey Makey for all kinds of capacitive touch inspiration: http://www.makeymakey.com/
I used conductive rubber silicone thumbs in this example. The instructable for making that fun material will come out in just a couple days as i finish it up!
One thing to note for anyone playing around with Capacitive touch sensing: you totally need to check out ADC cap-touch sensing! (the kind that this tutorial uses). It requires no extra resistors, AND most importantly, it works well even when your device is powered from a battery (unlike traditional cap-touch sensing).
I learned about it from the folks at http://hackteria.org/ and it solves so many of the problems with cap-touch sensing. It is really powerful!
Step 1: Materials
All you need is:
- Arduino Uno
- Gator Clips
- 4 Leds
- Piezo Buzzer (optional)
and here's the arduino code! https://github.com/quitmeyer/QuickQuiz
Step 2: Setup
Connect the LEDs to the Arduino's out pins 2-3, 4-5, 6-7, 8-9
Put the longer (positive) lead of the LEDs in the lower number pin (e.g. pin 2)
Connect the Piezo Buzzer to pin 11 (positive side) and the other pin to the ground.
Connect gator clips to the Analog Inputs from A0-A3
Connect the other end to something kinda conductive (again we used conductive rubber thumbs cuz it was weird).
Connect your arduino, and load this code
Step 3: Play!
The game is setup to lock-out other players for 4 seconds after someone buzzes in. You can change this however you want in the code. You can also change the threshold of the cap-touch for different types of materials you sense with!