Boeing Nose Wheel Tiller

[Boeing Skunk Works]

This is what's behind the sidewall. I don't think there is any feeling on it other than the cable tension and the nosewheel tying to return to center in the turn.

[jackpilot]

Thanks Mike...
I think I will use a small clutch as a break  on the axle, set for a light tension, and that will do the trick.
Maybe having a straight alu bar extending on each side of the axle with a light spring (extension) at each end could simulate the centering action of the wheel?

[Trevor Hale]

I'll do what Jack said...          I says Pardon...?  LOL.. Perhaps one of you tackling this when you get is mastered could produce a drawing..  Even in crayon would suffice..

Trev

[Boeing Skunk Works]

I worked on the tension setup and seting up the pot yesterday. I had a lot of ideas for this but none were any simpler than this.

When assembled into the sidewall there is quite a bit of smooth friction already from the shaft collars pressing against the Delrin bushings so not much of a spring was needed. It's not so much a centering spring as something that just increases the force needed to turn the wheel as you turn it farther.




The pot was set up very simply too. A hole was drilled in the rear shaft collar and a hardened steel rod was JB Welded into it and set at an upward angle (can't be seen in the photo) to intercept the toggle on the slide pot. This setup gives 100mm of travel with a minumum of parts.

I disassembled the mechanism and installed it into the sim last night, but I've yet to wire it and test it. Pot is 10K and gives a nice smooth linear reading on the meter.

Pot is mounted with 3M automotive trim tape to a 3/16" piece of foam board which in turn is mounted to the aluminum mount.




Installed in sidewall:




I think I mounted it almost an inch too low. Too late now. I should have checked closer but it's tough to get in there to see very well.

[Trevor Hale]

Mike,

It looks fantastic..  Absolutely Stunning.  I wouldn't have noticed the height issue, if you hadn't mentioned it.  Just WOW!

Trev

[jackpilot]

thanks for the tutorial Mike
Should get mine from Nick next week
.....another project

[Boeing Skunk Works]

That's OK, if you have questions please post them.

I wired it up and programmed it in FSUIPC after work. It works great though I thought I'd have more nose wheel throw than I do. I might play with the settings some, but it works well as is.

[mpl330]

Here's my 1st attempt at the tiller (courtesy of Mr S's idea) - needs a little adjustment (and a lot of smartening up to compare to Mike's  ) but it did work 1st time I connected it up via the BU0386 card 

Cheers
Mike

[Boeing Skunk Works]

If it works that's all that matters.

I was surprised I got the two terminals wired correctly the first time. I thought I'd have to use the 'reverse axis' function in FSUIPC, but I had a 50-50 chance.

FSUIPC couldn't have been easier along with Leo's card.

Another project completed. Now...what's next?

[when acting as a wave]

Man, that looks great! I really enjoyed watching the entire project's step-by-step development too. Excellent stuff.

[Boeing Skunk Works]

Thanks!

You would have loved my reverse engineering of a Sperry SP-50 AP.   

[when acting as a wave]

Ahh, and by the wonders of Google I found it ... And I must be learning something too, because I almost caught myself actually beginning to follow the conversation; there's merely a gap between my understanding of the objective and the mechanics of the eventual fix (which I guess would be the undertaking of the fix itself) 

Your explanations and photos are an excellent way to fill in said gaps, however.

And there's nothing quite like finding a problem just to solve it, eh?

[Boeing Skunk Works]

I just rewired it and powered the solenoids it so I could integrate it in the sim. The AP disconnect on the yoke releases all of the solenoids and one of the switches in the AP sends that signal to the card.

All of the switches except the roll knob and hydraulic system select work as designed.