Articulated Vehicle Steer Question

[JDH429]

Have been working on a design for an earth scrapper like a cat 657G and was wondering about the steering and if its possible to get away from using hyd cylinders on the pivot and using gear motors on all four corners instead and mixing the front two channels to work independently to steer the front end like a wheel chair works... The pivoting rear half should follow, No? Any one tried this? Sounds like it could work...

[pumptech]

Couple of years ago built the bruder wheel loader used screwdrives with servos , gear motors would work also , i used two servos / screwdrives , i reversed one of the motors , to get the push ,pull running on the same channel with a y harness .

[JDH429]

Hmm, good option as well.. or possibly linear actuators to do what you used the screw drives for. Thanks for your input.

[doodlebug]

Are you thinking of how the old Letourneau scrapers and tourn a pull's? I think that's how Steve built his project, http://rctruckandconstruction.com/sh...ght=letourneau.
Cheers, Neil.

[JDH429]

Neil, Thats basically what i was thinking. Thanks for the link to Steves build. I was thinking instead a ring and pinion deal like he did, using opposed gear motors in the axles like on a Stahl wheel loader...Im way off from any testing yet, just thinking about it. Thanks for your help.

[cosworth34677]

i'm using a 180 once servo in my loader for the stearing works great but it will try to center if you let go of the stick, it works for me

[andyathome]

Im in the process of redoing my rock truck.
I intend to fit a 6rpm motor with a small gear mated up to a large gear, both attached to opposite sides of the swivel.
will fit two limit switches to stop motor at max travel.
have used this before an a road roller with a 7kg drum and worked great, except never fitted limits and burnt out motor LOL.

there are many ways of doing the same job.


cheers andy