Nerf Dart Shooter
We've been working on this for some time. Danny built the original 'Pan & Tilt' using lego technic, following a design found on YouTube. We had to substantially modify it, adding lots of additional gearing for 'fine control'. We had intended to use GPIO signals from the Pi to control the motors in the Pan & Tilt mechanism, only using the Lego IR remotes to experiment with. But for simplicity we decided to retain the IR remote for controlling the motors.
Unlike others, who have built their nerf shooter by cannibalising the mechanism from an 'electric' nerf gun, we decided to go with a compressed air approach using CO2 from a mini gas cylinder to shoot out the dart from a Nerf Jolt. We had initially tried to make this work with a Nerf Triad, allowing 3 shots to be fired without needing to re-load. Unfortunately, we found the shots to be inconsistent with all 3 darts sometimes being fired at once!
The gas valve controlling the air burst is turned on and off using the signal from the Lego remote. To allow aiming, a small laser diode was added. This is also controlled from the Lego remote.
In use the shooter is surprisingly consistent when shooting a dart. It is important to align the laser dot with the point at which the dart hits once fired. The nerf dart flies with a very obvious trajectory!
Laser diode used to form the laser aimer. Resistor and diode limit current and prevent the voltages being reversed which could damage the laser diode.
Dan-ED with Nerf shooter mounted. The CO2 cylinder driving the shooter is mounted at the back. Control of the motors driving the Pan & Tilt mechanism is via a Lego IR remote. A second remote lights the laser aimer and opens the gas valve to fire the nerf dart. It is surprisingly consistent.
Pan and Tilt in action. It is relatively smooth. The gearing had to be modified to increase the gear ratio in order to provide 'fine control'.
The Pan and Tilt can steer the shooter with a high degree of accuracy! Once correctly aligned the nerf dart can consistently hit the 'red dot'.
Unlike others, who have built their nerf shooter by cannibalising the mechanism from an 'electric' nerf gun, we decided to go with a compressed air approach using CO2 from a mini gas cylinder to shoot out the dart from a Nerf Jolt. We had initially tried to make this work with a Nerf Triad, allowing 3 shots to be fired without needing to re-load. Unfortunately, we found the shots to be inconsistent with all 3 darts sometimes being fired at once!
The gas valve controlling the air burst is turned on and off using the signal from the Lego remote. To allow aiming, a small laser diode was added. This is also controlled from the Lego remote.
In use the shooter is surprisingly consistent when shooting a dart. It is important to align the laser dot with the point at which the dart hits once fired. The nerf dart flies with a very obvious trajectory!
Laser diode used to form the laser aimer. Resistor and diode limit current and prevent the voltages being reversed which could damage the laser diode.
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