A little video on noseweights

[NigelHutson]

Not wishing to open up a whole new debate on noseweights, but I thought this little clip was interesting. What do you think?

https://www.youtube.com/watch?v=4jk9H5AB4lM

 

[WoodlandsCamper]

Indicative, but the front of the car appears tethered to the front of the rolling road frame to hold its spacing, so that would induce damping in its own right.

 

[NigelHutson]

Yes, I agree, although it's the same in both examples. I remember "playing" with toy cars during my Collision Investigation training. We were talking about rear wheel lock up, and the instructors were saying that if the rear wheels of a car locked up, and the fronts didn't, the car would ALWAYS rotate through 180 degrees (unless it hit something). To demonstrate, the rear wheels on a toy car were stopped from rotating, and every time it was sent across the table, it rotated through 180 degrees! Hence the fitting of load sensing valves. It's a good way of re-living childhood days without the OH thinking I've gone totally bonkers!

 

[Raywood]

I did try to look this up but the link would not work.

 

[Dustydog]

When we were young we called them "hand brake U turns"

 

[Anseo]

https://video.xx.fbcdn.net/v/t42.1790-2/14593880_311296259248483_2610318171449589760_n.mp4?efg=eyJ2ZW5jb2RlX3RhZyI6InN2ZV9zZCJ9&oh=297341222baf55ee7f705420ba41960e&oe=57F38032

Link does not work for me either, url expired message

 

[NigelHutson]

Ray, the direct link does indeed seem to have stopped working. If you right click and then select "open in new tab", that seems to work.
Dusty, I remember those well too, although we hoped that they were "controlled"!

 

[ProfJohnL]

Not wishing to open up a whole new debate on noseweights, but I thought this little clip was interesting. What do you think?

j]https://video.xx.fbcdn.net/v/t42.1790-2/14593880_311296259248483_2610318171449589760_n.mp4?efg=eyJ2ZW5jb2RlX3RhZyI6InN2ZV9zZCJ9&oh=297341222baf55ee7f705420ba41960e&oe=57F38032

j
I can't get the link to work, so can you please give some other clue as to how we may find it?

 

[NigelHutson]

I have changed the link (which works for the time being).

 

[Anseo]

I have changed the link (which works for the time being).

Works now for me, thanks.

Anseo

 

[ProfJohnL]

Thank you Nigel, the clip now worked for me too.

This is actually quite an old clip and the same model was used by Bailey caravans on their exhibition stands following the work carried out by Bath University, and whilst scientifically you could pick a lot of holes in the model execution, it does display some of the important issues concerning instability with outfits. The clip is incomplete, as there was a more detailed explanation of what was actually happening.

If I remember correctly the demonstration was not so much about nose loads, but about the load distribution along the longitudinal axis and in particular "end loading" of the the trailer and its effect on yaw forces and motion.

Interesting to see it again, but its context has been skewed.

 

[Sproket]

This looks like the newer version ....
Notice the difference in the trailer beds for the simulation
https://youtu.be/qEWtBV9I0U4

And the older version is here
https://youtu.be/PFzrWHTG5e8

 

[ProfJohnL]

Hello Sprocket, Thanks for putting up another demonstration.

The earlier video is the one with the central spine on display, as this was actually used by the University as part of their test validation processes. They could easily move the test masses and repeat experiments with accuracy, The later video has the flat trailer which made it easier to demonstrate to the public about the types of load and their position.

You may note that if you allow the you tube video to run to the end you will see another video of John Wickersham using the same model.

 

[NigelHutson]

Good morning all,
Thanks for the second posting Sprocket.
The original video is very simplistic, but it does perhaps show to newbies the potential disastrous consequences of rear loading.
I'm certainly not trying to preach to the converted.
Nigel.

 

[LizziePope]

Thanks for posting it, Nigel. I'd seen it elsewhere and it's excellent. It is a great way to demonstrate clearly what the consequences are of getting it wrong.

 

[RayS]

Could we have the links written in full, please

 

[Hutch]

The links have been Great, Thanks Nigel. About a year ago I passed an HGV and just as I had passed it, my van got into a terrible tail wag for between 3 to 5 secons, thankfully the ALKO ATC kicked in and staightened the van and slowed us to about 50 mph and released again. Upon checking things, I had kept the nose weight to low to about 45 kg and had to much weight under the bed, Changed all this around, so now NW near to 90 kg. And next to nothing under the bed.

 

[NigelHutson]

EH52ARH, I'm glad that you survived the scare physically unscathed. A caravan in a snake is not a great feeling is it (been there etc., etc.)? I'm sure you found out that there's a huge difference between a car towing a caravan/trailer and an artic? The two main points are that the wheels of an artic trailer are right at the back (so would not get the pendulum effect), and also the fifth wheel coupling, which is generally sited over/slightly in front of the tractor unit's rear wheels, and if I can remember the legal jargon "not less than 20% of the load must be superimposed onto the tractor unit (or something like that)".

Nigel.

 

[NigelHutson]

RayS, does this help?

https://www.youtube.com/watch?feature=player_embedded&v=qEWtBV9I0U4
Hmmm, I typed the full link, but the video automatically pops up - sorry.

 

[RayS]

Thanks Nigel, that's the problem I had. I have caravanning friends in USA and Canada and quite often pass on gems like this. Not to worry, I'll get it back up and see if I can get it dwon from the Youtube banner.

 

[WoodlandsCamper]

Could you send them the link to this thread so they can see it?