Chain Drive

[Silcantar]

So, I was thinking about building a PF-powered Technic version of this vehicle, from the video game Borderlands:

More info

It would have 4-wheel drive, and the front wheels steer by rotating sort of like a chopper bike, along a mostly-longitudinal axis (you can kind of see the rotation point in the picture). I was wondering whether you think that a chain drive (one on each wheel) would be strong enough to power it, if I built it to scale with these wheels (standard on 1:17 trucks, I think)? Also, do you think I could get away with 1 XL motor for propulsion, or would I need 2?

[dhc6twinotter]

Sounds like a cool idea. I bet that suspension would have some great flex!

I've never built anything motorized using chains, so I can't really comment on the strength. However, looking at how the steering is done on that model, it looks like the chains would have to twist as each front wheel steered. That's probably not really a good thing. If you want chains, I'm sure there is a way to do it, but I think it would be simpler to just run a drive shaft through the center of your steering pivot point.

IMHO, 1 XL motor would work fine for the scale you are building at. However, you could use one motor per side to allow for a 360* turn.

Anyways, that's my $.02. It looks like a really fun project, and I look forward to seeing your results.

Daniel

[Silcantar]

It doesn't skid steer, so I wouldn't need two motors for that, just for power. I could use a drive shaft, but that would force me to make the frame even wider than it already is. The chain wouldn't twist (it wouldn't, even if I wanted it to); it would only be between the 16t gear and the 24t gear in this picture:

The Technic triangles connect to an old style turntable, which is where the steering will pivot.

Edited July 18, 2010 by Silcantar

[dhc6twinotter]

Ah, ok....I was wondering if that was what you meant. I think a chain would work, and if not, you could always just throw in a few extra idler gears.

I like the idea.

[roamingstop]

Could you not mount a small tyre / wheel onto the gear shaft (by bevel gear); and use wheel on wheel movement to power it and make a slimmer design?

[Silcantar]

Could you not mount a small tire / wheel onto the gear shaft (by bevel gear); and use wheel on wheel movement to power it and make a slimmer design?

I could, but it would rely solely on friction, and I'm not sure if you can get the wheels to just touch, without too much or too little friction. I've already got a lot of it prototyped in LDD already, anyways.