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A 'Portal' Sentry Turret to Guard Your DIY Lab

Need some security in your DIY workshop? Gadget Freak Ben Pawlowski and his team show you how to build a security camera/alarm modeled after the turret guns from the popular video game, Portal.

Inspired by the popular Portal video game franchise, Raxius Bloom, Martin Miller, Ben Pawlowski, and Giovanni Velez decided to create a model turret gun modeled after the ones featured in the game. Within the lore of the game, the turret is advertised as a consumer-grade version of a military defense turret that is intended to be used in the home to protect loved ones. It has the ability to locate, track, follow, and execute commands once a target is found.

The turret operates in four different modes (demo, friendly, sentry, and defective) and will track a target and sound an alarm based on if an intruder is an enemy or not. It is also programmed to speak and play different songs depending on what mode it's in

Parts List    
Amount Part Description Allied Part #
1 Arduino Mega  
1 eSun PLA 3mm Filament Black + White  
1 LM386N Audio Power Amplifier  
1 Pixy (CMUcam5) Smart Vision Sensor  
2 Micro Servo Motor TowerPro 9G  
1 HC - 05 Bluetooth Serial Module  
1 Adafruit Audio FX Sound Board with 2MB Flash 70460758
1 Galaxy Note 3 (Or any bluetooth capable device)  
24 Red LEDs 70054144
1 Speaker  
1 Aux cable 70302568
1 Protoboard and breadboard 70012513
1 Solder 70177921
1 copper wire 70825765
1 Assortment of resistors and capacitors 70022898
3 9V battery connectors 70181688
1 Battery pack for AA batteries 70182566

Click the image below for a slideshow of the build instructions.

Click here to download full build instructions including source code.

The eye of the turret uses a signal recognized from the camera and follows the signal's movements in real time. A gimbal inside the eye allows for a full range of motion within 180 degrees (90 degrees up, down, left, and right). If the signal is determined to be an “enemy” it will trigger a sound from the FX board notifying the successful acquisition of the signal and begin “firing” the guns mounted on either side of the turret. Figure 1 shows the basic components from the front view.

Do you have a cool, original, homemade gadget you'd like to share with the world? Give us the details at, and you may receive $500 and automatic entry into our $6000 Gadget Freak of the Year contest!

[All images courtesy of Ben Pawlowski]

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