Quote:
Originally Posted by euromodder
Whatever its merits, I've always felt Phil's solution was way too complex to work IRL.
It's got to be done the easy way to work - KISS.
* Optimised for straight line duty and slight turns, i.e. highway style driving.
--- Don't bother about streamlining in slow hard turns
* Gap filling plates hinged on the tow vehicle
--- outboard movement to be restrained by bungee cords
--- inboard movement physically restricted by solid stops, yes, this will leave a gap on the outboard side in a hard turn - that's not an issue
--- downward movement of the top plate to be physically stopped by the sideplates , upward restrained by bungees
--- bungees might be fixed to the physical stops for the gap-filling plates, but not too far aft on the plates in order not to bend these.
* front side and top of the trailer to be rounded
--- helps even without the gap-filling plates
--- rear end of the gap-filling plates to rest on the rounded front, using teflon wheels on the plates
--- small, locally applied teflon plates on the trailer where the above wheels go as the plates slide over the front of the trailer
|
The most challenging hurdle I ran into was when in a low speed turn,with trailer cocked,and on the sloping crown of the roadway,and the tow vehicle was ascending a laterally-level up-slope.
With only aluminum skins on the outside of steel-truss skeleton plate frames,the side plates would snag underneath the top plate and destroy it as it was displaced span-wise.
By moving the side plates onto the trailer by use of the lolly-shafted C-frame,the side plates cannot bind against the trailer during any type of orientation,nor the integrator on the back of the tow rig.
The upper frame has skids and rollers which are in constant contact with the trailer.As soon as the trailer displaces in any manner,the upper plate can raise to clear.An upward displacement of the trailers tail causes no interference.
I've yet to finish the lower plate(s).Those will have to wait 'til after the A2 Wind Tunnel.
As far as bungees or springs,I found that the side plates would be required to swing a full 90-degrees to clear the trailer face at 'full-lock',and no bungee or spring could maintain tension while 'straight',without being stretched beyond it's elastic limit and permanently deform when at full 'turn.'
I ended up with something akin to cable/pulley/double-hung window sash weights, riding vertically inside no-snag elevator shafts.These can handle the entire range of motion without damage.
It is complicated but has survived over 5,000 test miles without a hitch.
I recommend that the nose of the trailer be just as close to the tow ball as possible to allow the side plates to be as short and as light as possible.
When you strike a pothole or pressure ridge in the roadway it causes 'jerk,' which is an instantaneous acceleration,and can easily destroy structures who's inertia/momentum loads can be overcome during these 'instant' transient loads.
