Simple AWS prototype

[Becs]

Hi all.

Since I first got my hands on a 8880 I have been fascinated by the concept of AWS on a normal car. But I thought a permanent AWS like on the 8880 could be quite dangerous att high speeds. An adjustable AWS system would be better. I thought about rebuilding the 8880 and upgrading the steering, but I lacked the skills and patience to even try to think of a reliable way of building it. Over the years I have gone back to this idea but never got any closer to a solution.

Until when the 9398 came and we got the servo. Now there was a simple way of doing it, instead of a mechanical solution it would be an electrical. Only, two servos would be needed.

Last week I finally got my hands on a second servo and yesterday I built this simple prototype.

By connecting one servo through a switch you get a easy choice of three steering modes.

Normal:

Sharp, like 8880:

And slight crab steer:

I also made a simple gearbox with two motors with different gearing joined through a differential and the slower motor connected to a switch.

Thus giving it three speeds. Controlling both switches at the same time gives easy handling: Agile steering at slow speeds, normal steering at medium speeds, and slight steering at high speeds.

It is really fun to drive around with, unfortunately I didn't have enough time to make a video before leaving my Legos for the week. I will try to get time for it next weekend.

Hope you like it

Happy building

Becca

[lukeandahalf]

Looking forward to the video! Looks great so far, multiple steering and speed controls makes it all the more interesting.

[Junpei]

Looks great, I can't wait to see the video. Zero steer would be pretty much impossible, right?

[skriblez]

Nice work. Looking forward to the video :)

[aol000xw]

How does that motor setup work in practice?

I've got the feeling that one motor will work against the other. The movement will follow the "less resistance path", so in a climb with only one motor working the vehicle could stop while the stopped motor is driven backwards by the running motor. With two motors working I think one will work way harder than the other, on a climb steep enougth the slow one might be dragged by the fast one, and on flat terrain the fast one dragged by the slow one.

But all of this is just my guess, thats why I ask how does it work, really interested on what happens when climbing.

[Becs]

I'm happy you like it. I wish i could take credit for the halfway done bodywork though I found it here a long time ago, someone tried to make a Toyota Celica, I think. I copied it in an attempt at completing it, but I got no further. Thought it could fit here for a splash of colour.

@TwentyLeggedHen

It depends on what you mean with zero steer. It does not steer if you dont want it to, with all wheels pointing forwards Otherwise I can't think of any way to get something called "zero steer".

@aol000xw

You are right in doubting the practicality of the setup. It does work great on flat surfaces with no obstacles. But because they work against each other in low gear it doesn't take much force to hinder it. It works in the opposite way of a normal gearbox. Can't get over the hill? Shift to a higher gear and take it with speed

Maybe, if it will stay together until I'm done with my current project, I might a serious attempt of completing it. I would, however, make a conventional gearbox instead.

Happy building

Becca

[Becs]

Hello everyone,

I had some time this weekend to make a small video.

Here it is:

Becca

[Junpei]

Looks great! It seems to be struggling around 1:13, is it just the video?

[Becs]

Thank you. Hm.. I think that was only me struggling with the remote.

[Lipko]

Well, this seems to be perfect, since it can shift modes even when it's steered.

I want to make a telehandler once and make a manual version of this steering. I already have an idea but I would love to see other ideas too.