After the competition got extended for another month, I decided that my first submission was not worthy enough for a two months long competition so I decided to start designing this fully automatic turret. This does not need any human interaction apart from turning it on and refilling the magazine when it's empty.
First thing's first, Tobias Frank's turret design (http://tec.artstation.com/projects/1bk9Z) inspired me to follow a similar design pattern. Apart from the design idea, the whole mechanism has been planned by me. The coding was also done by me but a friend of mine helped a bit in the end when I was running out of time.
So the basic operation is the turret rotates 60°, seeking any sort of obstacle using ultrasonic sensors. As soon as the sensor detects an obstacle present within the prescribed distance (via coding), the servo that rotates the turret pauses and the flywheel turns on. At the back, there is a stepper motor that pushes the darts from the magazine into the flywheel and the flywheel pushes out the dart. As soon as the obstacle is removed, the turret goes back to rotating state, seeking further obstacles.
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