Option #1:
New suction carrrr!
You may notice that for the time being, I've named it Parkour, because I can't think of anything else and Parkour is a lot better than "suction...vehicle...thing". If anyone thinks of any better names then there's a comments section. Anyways, here's a better idea of what Parkour looks like:
Ohhhh yeah, going for two fans this time. It's still going to be powered by Pololu's micro metal gearmotors, since they've proven they're worth their weight in gold, and will grip everything via Pololu's awesome wheel/tire sets.
So this thing is very very wide because when a vehicle is turning like a tank, it simply performs better the wider it is relative to it's length. As far as the huge 90mm tires are concerned...well, this screenshot says it all.
Parkour is designed to be able to go around the outside edge of corners. The huge tires and substantial ground clearance will also aid it in conquering just about everything else too, of course, from deep grooves in the sides of buildings to interior 90 degree transitions, which suction car v1.0 needed a couple extra angles to conquer.
Besides opening the doors to pretty much any terrain, I'm also working to improve upon all of the other minor little issues with suction car v1.0 that bugged me. To start off, Parkour operates off of one battery.
One. Battery.
Instead of, you know, three. I plan to use one of these. This will give me the same 4S power and twice the capacity, which will be awesome since I'm shooting for at least a 10 minute run-time this time around. Further improvements include actually having enough chassis space for all of the components, and using hacked servo boards to control the drive motors, instead of shitty R/C airplane controllers that decide to stop working sometimes, and won't reverse. So now, besides being able to reverse out of bad situations, I'll be able to actually turn in place, with the outside tires moving forward and the inside tires moving backward, instead of just having the outside tires moving forward and the inside tires doing nothing. Maneuverability was always a bit of an issue with SCv1.0.
Oh, everyone stop for a second and look at how much effort I put into modeling the Pololu 90mm tires/wheels for this project. I don't know how many grooves there are around the real tires, but mine have 210 little grooves all the way around. I feel like a god, knowing my creation so well.
Onward.
Option #2:
Yes, it's a gun. No, it's not designed to kill people.
...and yes, I have contemplated mounting it on Parkour and calling it one project.
It's basically a baseball pitching machine, except scaled way down and designed to shoot elongated projectiles through a barrel, hopefully at a much higher speed and accuracy. I've actually been toying with this idea for a very very long time...like, years.
Everything's pretty compact in this design and therefore hard to see but I'll try to explain as best I can.
The projectiles are going to be made out of something cheap, readily available, easy to work with, and 1/4" in diameter. Sounds like wooden dowels to me. Here's a screenshot showing the loading device. There's just a tall gravity-fed ammo rack that holds the wooden dowel segments, and at the bottom a servo will work an arm (not in the drawing...yet) that pushes the lowest dowel into the giant spinning wheel which then propels it to
Maybe that's a better view. Here you can also see the second standard size servo I have mounted underneath the entire assembly, which will be used for the tilting portion of the pan/tilt mount that I want this gun to be mounted upon.
The reason the projectiles are going to be so long (two inches, actually) is pretty simple. The giant rubber tire that will be propelling them is going to be spinning at somewhere around
That being said, the barrel on this thing actually needs to be the opposite of a real gun...very short; just long enough to make sure the projectile is moving straight. After the wheel is no longer accelerating the dowel segment, the only thing that projectile is doing is slowing down, and will do so at a higher rate if it's traveling through a barrel with friction.
So why'd I only go with one tire to accelerate the projectiles, and not two? Well...I didn't find it necessary for one, since the projectiles are elongated and won't start spinning like a ball would if spun by a single giant tire. Baseball pitching machines need two wheels to be any good because they're pitching...balls. Also I went with one tire for the sake of being compact.
Oh yeah:
On the other side of the giant wheel are ball bearings, so that eliminates the huge amount of friction that would have been present if the projectile was being pressed against the other side of the barrel as the drive-wheel propels it.
I guess that's pretty much it for the wheel gun. When I first began designing it, I had a second drive motor at the end of the barrel that was angled ever so slightly, to put a spin on the projectile, but that turned out to be too much of a pain in the ass. Also, right now it's semi-automatic. I really want it to be fully automatic because that would be awesome but I'm still working on figuring out the best way to make that dream come true.
So...both are still only about 90% finished, but...Parkour, or wheel gun? I can't decide.