New HGV braking system !!!

[hygt2]

http://www.bbc.co.uk/news/business-32845386

Very clever controller by Dave Cebon (knows what he's doing and has been doing it for over twenty years). I still remember him from my student days

Apparently they have developed a very, very speedy control valves for the pneumatic braking system, which can now cycle at speeds very close to those for a hydraulic ABS system.

Historically, my understanding is that the pneumatic ABS control valves worked at a 1 second cycle speed which is really not as effective as those in a car !!!

[stevieturbo]

Lorries have ABS ?

And lorries dont jackknife anymore ?

I dont know about you, but I've seen plenty of lorries lock the trailer brakes and start to jackknife, only the driver letting off stops it going further.

But if they could introduce such systems to lorries, compulsory fitment would be a no brainer.

[k20erham]

hi yes for quite some years hgv's have had ABS and traction control, they have always had some kind of load sensing control on both the tractor units and trailers.these are to assist the driver when certain conditions can cause a jack knife its not always the locking of the trailer wheels that's the problem, the laws of physics are demonstrated when if the practice unit slows faster than the sum mass of the trailer especially in the wet the total energy gets transmitted into the tractor unit via the trailer coupling or king pin, this has the effect of pushing the tractor unit sideways just like are car that's got too much rear brake bias. 9 times out of 10 the driver doesn't have the time or space to release the brakes to stop it. the modern stuff helps and normally saves the day.

[hygt2]

stevieturbo said:

Lorries have ABS ?

And lorries dont jackknife anymore ?

I dont know about you, but I've seen plenty of lorries lock the trailer brakes and start to jackknife, only the driver letting off stops it going further.

But if they could introduce such systems to lorries, compulsory fitment would be a no brainer.

Yes, lorries have had ABS from c. 20 years ago. However, as k20erham said, the energy stored in the trailer is a major factor in slowing down.

Also, the existing pneumatic ABS control valves works at c. 1-second cycle speed. As a result, when the ABS kicks in, the lorry would spend a lot of time NOT braking ...