This instructable will help you make a hand that raises its middle finger if something gets in close proximity of it. It was a project for my Game Design (Games and Interaction) study at the HKU.

Step 1: Hardware and Parts Required:

Hardware:

• 1 Arduino Yun

• 1 Breadboard

• 1 Piezo Buzzer

• Jumper wires (I used 23)

• 1 Servo

• 1 Ultrasonic Distance Sensor (HC-SR04)

• LED lights (optional)

• 220Ω Resistors (optional)

Other Parts:

• 1 Glove

• Duct Tape

• Cardboard

• 1 long and solid object. For example a small steel pipe or a wooden plank. Personally i used a butter knife.

• Something to stuff the glove with. I used toilet paper which works fine but u can use many other materials to stuff the glove with.

Step 2: Arduino Hardware Setup (Fritzing Image):

Black cabels are the ground cabels and red cabels are the power cables.

The ports you attach your cables to might differ depending on your code.

I programmed the Arduino to execute certain commands if the distance sensor measures a solid object within 50 centimeters of itself. Within those 50 centimeters the closer the solid object gets to the sensor the more the servo will move the finger up and the higher the tone produced by the piezo buzzer becomes. I also added that if a distance within 50 centimeters is measured two LED lights will light up.

If the sensor doesn't measure anything within 50 centimeters nothing happens. The fist remains closed.

Step 3: Arduino IDE Code:

First you'll evidently need the Arduino IDE to be able to write code and upload it to your Arduino. It's available for download here: https://www.arduino.cc/en/Main/Software. You also need this to open the file you can download below.

The file below is the code I wrote... Bare in mind that it is far from perfect. With this code the servo is unstable. From time to time your Arduino will freeze for a few seconds. I did not yet manage to fix this as I have trouble with using delays and millis. Anyway here it is:

Arduino Code For Middle Finger.ino
Download

Step 4: Final Step - Build the Hand:

Keep in mind that this is just the way I've done it. I'm sure there are many less makeshift ways to build a hand but this worked for me:

First you grab the glove and start stuffing the fingers, except the middle finger, with toilet paper and cardboard (or whatever material you chose). Then you make a middle finger in such a way that you can firmly attach it to the servo. I made the middle finger by wrapping toilet paper around some iron thread and then wrapping both in duct tape. Once you attached the middle finger to the servo, you must then attach the servo to something that will withstand the servo's push when it changes positions. For this I used a knife but any similarly long and solid object will do. I once again used duct tape to attach the servo to the knife. You then push the knife and the middle finger into the middle finger compartment of the glove. You can then stuff the glove some more with toilet paper. Once the glove is stuffed you can bend and attach fingers in such a way it seems like a close fist. Do this as such that the middle finger does not get stuck in the fist when the servo tries to move it up. Finally I made a makeshift arm with cardboard and duct tape around the bottom part of the knife in such a way that you can put it down on a table without the hand constantly flipping over.

Step 5: Enjoy Flipping People Off!!!

Once your prototype works you can place it next to something of which you want people to keep their hands off. If they still take, touch or even reach for it they will be flipped off and hopefully think twice before they would do it again. Nobody likes to be flipped off!