Emergency braking at it's best!

Dymo

This just looks crazy, and with a fully loaded trailer.

On a test track in the new Volvo FH, together with test drivers you get to experience how the Collision Warning with Emergency Brake system can avoid a rear end collision, even if its tight!
The tractor trailer is fully loaded to 40 tons GCW.

https://www.youtube.com/watch?v=ridS396W2BY

Any truck drivers out there with opinions on this?

mickdw

Dymo wrote: »

This just looks crazy, and with a fully loaded trailer.

https://www.youtube.com/watch?v=ridS396W2BY

Any truck drivers out there with opinions on this?

Almost looks like the truck is tethered to something. The truck must be travelling v slowly.

JustLen

It says on the clock its travelling at 60. Would that be miles or KM?

T-Maxx

Brown underpants moment if you're seeing that in your rear view mirror.:eek:

slimjimmc

JustLen wrote: »

It says on the clock its travelling at 60. Would that be miles or KM?

Km/h. It's written under the "20" on the speedo.

BrianD3

Here's a video from the ADAC which has footage of a MAN artic braking automatically. To illustrate the value of such systems video also shows what happens when a small truck (5.5 tonnes) hits a line of cars at 70 km/h

https://www.youtube.com/watch?v=s-8mbaRUj88

Mycroft H

Mercedes have a similar system.

Damien360

Dymo wrote: »

This just looks crazy, and with a fully loaded trailer.





Any truck drivers out there with opinions on this?

Wow. That is impressive. I would'nt fancy being the test driver in the white volvo for that. Looks like the truck did not break during initial warning and waited until very last second when driver did not intervene. Plenty of time for driver to take control himself. It would be very expensive brake pads to get that to work without serious overheating.

Dymo

Small price to pay for avoiding a near fatal accident.

Cuddlesworth

Interesting system. Looks like the cab and engine pivot over the front axle under braking, creating huge amounts of weight driving down on the tires. The more break force used, the more weight pushing down on the front tires, the more grip the tyres have which means more braking power.

Actually with the way electric cars have choice in where they position the batteries, we could easily see similar systems using a percentage of the batteries over the front wheels.

guil

Cuddlesworth wrote: »

Interesting system. Looks like the cab and engine pivot over the front axle under braking, creating huge amounts of weight driving down on the tires. The more break force used, the more weight pushing down on the front tires, the more grip the tyres have which means more braking power.

Actually with the way electric cars have choice in where they position the batteries, we could easily see similar systems using a percentage of the batteries over the front wheels.

That's just the cab suspension throwing the cad forward like that, takes very little braking to get it moving around a bit

colm_mcm

I would've thought the back brakes would do most of the work on a truck?

JabbaTheHut

colm_mcm wrote: »

I would've thought the back brakes would do most of the work on a truck?

Not really. Especially if it's EBS brakes.

OP. How do you know it's loaded to 40 tons gross? It brakes like it's unladen. If it brakes like that at 40 tons, then they're some brakes, emergency braking or not

Supergurrier

Impressive stuff, got to have alot of respect for a firm like Volvo single handedly carrying out such expensive research because the can

Mycroft H

JabbaTheHut wrote: »

Not really. Especially if it's EBS brakes.

OP. How do you know it's loaded to 40 tons gross? It brakes like it's unladen. If it brakes like that at 40 tons, then they're some brakes, emergency braking or not

Says in the video description on you tube!

Mr Simpson

This video shows what can happen when trucks crash (full ep of traffic cops). Great system imo

https://www.youtube.com/watch?v=NXPWjIpVTx8

Pottler

Excellent systems on the trucks. What I'm taking from this though, is that I'm buying a bigger car...

Mycroft H

Looks like Volvo are well ahead of the Curve in this (auf Deutsch)

I suppose it's no surprise coming from a company with so many pioneering road safety techniques.

dmc17

Hope it's more reliable than this one

Mycroft H

^ I think that was back in 2007 or so. I'd say the technology has improved a little bit since then.

Mr Benevolent

MarkMc wrote: »

This video shows what can happen when trucks crash (full ep of traffic cops). Great system imo

Sobering for any driver. The NCAP test doesn't cover rear collisions.

Pottler

dmc17 wrote: »

Hope it's more reliable than this one

I'd love to have been in the de-briefing meeting. "So Olaf, you muppet, how did you manage to feck that up???":D

kirving

Plus, it wasn't turned on properly, and was a prototype system.

The weight of the truck shouldn't affect braking distance, once the components are up to the job (ie: you're limited by the friction of the tyres rather than the disks/pads). The required braking force depends on the mass of the vehicle, but the maximum friction force which can be applied through the tyres also depends on the mass of the vehicle.

I love these types of systems. (My final year project is to develop a telemetry system for a Formula Student car, which involves using lots of the same sensors that are used in these types of systems. More info for anyone interested in my sig)

Cuddlesworth

guil wrote: »

That's just the cab suspension throwing the cad forward like that, takes very little braking to get it moving around a bit

Cool. Could only go on what i can see. Any idea how a 40 ton truck can brake like that? That seems better than my motorbike on a hot day with sticky tires.

Super sticky tires on the truck? Ones that no actual haulage company could afford to run.

deandean

Very impressive! Mind you it was a volvo car that the truck was going to hit, tbe VOVAS (Volvo on Volvo avoidance system) would have kicked in tbere too. a toyota in front would have been run over ;-)

Mycroft H

Just don't go googling VOVAS in work lol

paddyland

Those trucks were all emergency braking in a straight line.

What happens on a curve?

kirving

I imagine that there is a number of radar scanners on the front of the cab high up which would help visibility around corners.

On a blind bend, there's only so much it can do but a computer can brake almost instantly, where it would take a human half a second to react - at the vert least miniming the impact speed. The system should balance brake forces to keep the truck on course on a bend too.

It really wont be long before crashing a new car will be a difficult task.

Cuddlesworth wrote: »

Cool. Could only go on what i can see. Any idea how a 40 ton truck can brake like that? That seems better than my motorbike on a hot day with sticky tires.

Super sticky tires on the truck? Ones that no actual haulage company could afford to run.

Required stopping power is proportional to weight. But, the more weight you have, the more force on the front tyres, and the more grip they have.

You're right about the tyres, but the system would constantly gauge the grip level of the tyres during normal driving, and again as it senses an object.

BorneTobyWilde

My opinion is the truck behind the Volvo truck has no chance of stopping, So yea new truck avoids dickhead who stops in middle of truck, But new truck gets hit from behind,
While dick head drives off with his head in the clouds , totally unaware he caused a 50 vehicle pile up.

corkgsxr

I prefer the merc one that doesnt wait till your about a meter away before trying to stop

mickdw

Id like to see how the stopping distance of those trucks compare to a new family car. When I started watching that volvo truck video, I thought it was going to be a system to aid control as it avoided the obstacle. Quite odd to see it actual pull up in time.

Popoutman

Kevin Irving wrote: »

The weight of the truck shouldn't affect braking distance, once the components are up to the job (ie: you're limited by the friction of the tyres rather than the disks/pads). The required braking force depends on the mass of the vehicle, but the maximum friction force which can be applied through the tyres also depends on the mass of the vehicle.

Though the total mass of the braked object will definitely have a bearing on braking distance. The brakes will be able to dissipate the forward momentum at a particular rate, and this rate is determined by either the tyre/road interface, or the brakepad/brakedisk interface, whichever is lower. The vehicle mass, if higher, will certainly result in a longer braking distance. More mass, more momentum, more energy to dissipate. This means a longer time to dissipate more energy, when the rate of dissipation is limited.

It's bit of an oversimplification to think that the extra mass will give a directly proportional increase in dissipation rates at the road/tyre interface.

Esel

MarkMc wrote: »

This video shows what can happen when trucks crash (full ep of traffic cops). Great system imo

Too many talking heads for a 28 minute video (based on a number of FFs).

I do like the automatic braking in the first few videos in this thread though.

Some newer cars have auto braking when/if the driver stamps the brakes then lifts off immediately though - probably delevoped as a result of such drivers (new to ABS; stamping pedal) lifting off the brake pedal when they freak on feeling the pulsing feedback through the pedal.

Mr Simpson

Esel wrote: »

Too many talking heads for a 28 minute video (based on a number of FFs).

OT, but yeah there can be, its a good show though. The crash in it is mental, poor girl had no chance.

Can heavy braking (particularly on wet or icy roads) not lead to jackknifing at all, with articulated trucks? Or have I got that all wrong?

Presumably they didn't show any wet-weather stuff as the technology is still in it's infancy in that regard? I'd imagine there'd need to be sensors or such attached to the bottom of the cab or wheels to gauge how wet they are at any given time, and it calculates the stopping distance accordingly or something to that effect?


It seems a very sophisticated system. Between this and cars that are learning to parallel park themselves, you'd wonder what's next for vehicle technology.

Mr Simpson

I think if the trailer brakes as well it shouldn't jacknife. I'd say its more if you brake and try to avoid then it would jacknife, I could be wrong though

Jimdagym

This is going to mean a huge increase in the number of people going under the back of a 40 foot though...

bijapos

BorneTobyWilde wrote: »

My opinion is the truck behind the Volvo truck has no chance of stopping, So yea new truck avoids dickhead who stops in middle of truck, But new truck gets hit from behind,
While dick head drives off with his head in the clouds , totally unaware he caused a 50 vehicle pile up.

Firstly if the truck driver behind is paying attention they should have a better chance of avoiding a collision, along with this every new truck will have this system fitted after 2015, some from 2013 so it's a rolling introduction that wil lsoon be in most trucks.

Secondly the "dickhead" who stops in the road is probably stopped at the end of a traffic jam or behind an accident, they might not just be driving with their head in the clouds.

Something like this:

Paulo Jorge da Silva, 46, is claimed to have shown "gross inattention" when he failed to notice a tailback of traffic on the M6 near Sandbach in Cheshire as he approached at 40 mph.
His truck laden with fruit juice cartons smashed into the back of a Toyota Previa carrying couple David and Michelle Statham and their children.
Mr Statham ,38, a chef, Mrs Statham, 33, and their children Reece, 13, Jay, nine, 20 months old Mason and ten weeks old Ellouise died instantly in the night time accident last October.

BrianD3

Off topic but this thread shows the value of paying close attention to what's happening behind you and thinking about escape routes when you're stopped in a tailback. Simple things like leaving enough room between you and the vehicle in front so that you can maneouvre if necessary. As the ADAC crash test and the real life crashes in this thread demonstrate, a car's occupants are extremely vulnerable if their car is stopped behind a line of cars or HGV and is rear ended by another HGV. The impact speed of the M6 Previa crash was only 31 mph yet 6 people were killed instantly.

kirving

Popoutman wrote: »

Though the total mass of the braked object will definitely have a bearing on braking distance. The brakes will be able to dissipate the forward momentum at a particular rate, and this rate is determined by either the tyre/road interface, or the brakepad/brakedisk interface, whichever is lower.

The road/tyre interface will generally be your limit, since brake pads can exert huge pressure.

The road/tyre interface is the important part, and the coefficient of friction here depends directly on the force applied to the front wheel , which in turn is proportional to the weight of the vehicle.

goz83

Fred Flintstone would be jealous

trixyben

BorneTobyWilde wrote: »

My opinion is the truck behind the Volvo truck has no chance of stopping, So yea new truck avoids dickhead who stops in middle of truck, But new truck gets hit from behind,
While dick head drives off with his head in the clouds , totally unaware he caused a 50 vehicle pile up.

This is what I was thinking, truck with this auto brake technology does its job and prevents a crash with the car in front only to be rear ended by car from behind...

So would the idea of dash cams front and rear of the truck limit any liability on the truck drivers behalf if indeed it was the car in front of him who was really at fault and as i have witnessed before they would drive away regardless if they knew what happened are not

Popoutman

Kevin Irving wrote: »

The road/tyre interface will generally be your limit, since brake pads can exert huge pressure.

The road/tyre interface is the important part, and the coefficient of friction here depends directly on the force applied to the front wheel , which in turn is proportional to the weight of the vehicle.

In a lecture or theoretical discussion with perfectly linear characteristics, yes you are right.
In the real world with non-linear tyre contact patch behaviour, increased deflection in suspension components, changes in brake behaviour with increased temperature and heat transfer limits being reached and other factors like this will adversely affect the braking performance, leading to longer braking distances..

GreeBo

trixyben wrote: »

This is what I was thinking, truck with this auto brake technology does its job and prevents a crash with the car in front only to be rear ended by car from behind...

So would the idea of dash cams front and rear of the truck limit any liability on the truck drivers behalf if indeed it was the car in front of him who was really at fault and as i have witnessed before they would drive away regardless if they knew what happened are not

But wouldnt this following driver/truck crash anyway? At least in this case its now just hitting a truck, not a truck that has already mashed through a bunch of cars?

tu2j2

trixyben wrote: »

This is what I was thinking, truck with this auto brake technology does its job and prevents a crash with the car in front only to be rear ended by car from behind...

So would the idea of dash cams front and rear of the truck limit any liability on the truck drivers behalf if indeed it was the car in front of him who was really at fault and as i have witnessed before they would drive away regardless if they knew what happened are not

Is this technology only there to negate the effects of truck drivers driving up the hole of a car or not paying attention to the stopped traffic infront?

The car infront isn't causing the truck to do its emergency braking thing, the truck driver not paying attention is (In 95% of cases)