For Halloween this year, I decided to build a machine to launch 'Rockets' at the children that come to our door.
If you live in the United States, you may know these candies as 'Smarties'
The LEGO Mindstorms Robot Inventor kit has these nice wheels, which I thought might work.
The grid spacing actually works perfectly for these candies, so I didn't even need any kind of tensioning system.
Now to add a motor and see what happens.
Hmmm, does not launch them at all, we need to spin the wheels faster.
We'll try gearing them up 3:1.
A bit better, but still not great.
Let's gear it up another 3:1.
Hmmm, some bad speed wobble. We need to constrain the wheels better.
Much better.
But I think we can do even better. Adding a second motor will help overcome friction and prevent slowdown when the candies are launched.
🚀 To the moon! 🚀
Now we need some sort of feed system.
We'll build a channel and let gravity do most of the work.
This bar will push the bottom candy into the wheels.
And we'll use a motor to activate it.
Let's increase the capacity.
We need something to stop the entire stack from being pushed forward.
This panel should do it.
There is just enough space below it to allow a single candy through.
Now let's build a base so we can aim it.
Turns out these wheels also make a decent base for a turntable.
Now to add some gearing to a motor.
Now to build out the base, all suspended above the turntable wheel.
Let's build the Mindstorms unit into it, and add some wheels so it can glide over the surface.
Now we need to suspend the launch unit above it.
It's suspended at the back so that it can tilt.
Now to add some tilt control.
I've already used all four motors that come in the Mindstorms kit, so I had to get a Powered Up one.
Now for some testing.
We'll just remote control it for now.
Now for some Halloween testing.
Let's see if we can get one in the pumpkin. 🎃
It can launch these candies over 8 feet/2 meters.
Oops, one of them fell out of the feeder. Clearly could still use some work!
Success!!!!😄
We got two in, at least!
I will post instructions for some version of this soon. Thanks for watching, and Happy Halloween!! 🎃👻🦇
I ate way too many of these while building this....