Quick and dirty stepper-motor driver tripod turret
Motorised gun turret
I’ll be honest, the overall effect isn’t as exciting as I’d hoped. Mainly because the stepper motor I chose only had a small number of steps per complete revolution.
I think I counted 20. Which means that each single step is 18 degrees.
Even with micro-stepping, it means that the turret jumps almost ten degrees with every step. The main problem this causes is that the movement becomes very “jerky” if played back at a relatively slow speed (since the gaps between steps become pronounced.
So I had to speed up the time between steps.
The delay between steps is currently set to 25 milliseconds.
That means to complete a full rotation would take 20 x 25ms = 1/2 a second. That puts our gun turret at two revolutions per second, or a whopping 120rpm!
That’s really too fast to be of any use.
But until I can find either a geared stepper in a similar size, or a stepper with many more steps per revolution, it’ll have to do (the circuitry can remain the same for almost any stepper motor, so changing the actual motor should be relatively easy).
I think I’ll add some trickery to this, so that it’s compatible with my app-enabled hardware, used for the Titan Forge Cyber Punk diorama a few weeks back – it may look a bit rubbish, but being able to rotate a gun turret through a phone app has got to be pretty cool, hasn’t it?
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