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Keeping brakes compatible

Steve Skinner, Australasian Transport News (ATN)  /  October 18, 2016

There will soon be plenty of guidance for getting the best out of not only foundation brakes, but the much more complicated electronic systems as well

Chris Loose reckons English is a second language for a lot of engineers.

And that’s why Loose and numerous other technical experts who have been working on a guide to braking and stability performance for heavy combinations, are trying to keep it simple.

"We don’t want to overcomplicate it," says Loose, senior engineering advisor with the Australian Trucking Association (ATA). "Every operator who tries to read an engineering book won’t go past the title.

"We made it is as easy to understand as possible. An operator will focus on three key tables, and that’s probably all he’s going to have time for"

Those three tables are in the draft document which still needs real-world testing by operators.

The tables involve ratings across four classes of brake systems and three types of braking conditions.

The first class of brake system is what are called "dumb" brake systems, which are air only. The second type is load sensing valve brake systems, which are mechanical and air. The third is anti-lock brake system (ABS); and the fourth – and smartest – is electronic stability control.

These systems are rated against light or "normal" braking; heavy or "harsh" braking; and cornering or roll stability.

Smart truck and dumb trailers

The truck might have stability control, and the trailer might have TEBS (trailer electronic braking system) with roll stability, which would give the combination the top rating for both braking and roll stability.

But if the operator doesn’t plug in the power, it’s a dumb trailer.

Loose adds that with longer combinations you have to make sure the power goes right down to the back end -- at least 9 or 10 volts at the last control unit. "Without electrical grunt it’s (also) a dumb trailer."

And don’t try to stick a 24 volt lead into a 12 volt ABS system: "That will blow it up."

The tables apply equally to trailers attached by both fifth wheels or drawbars. However truck and dogs are inherently more unstable than semitrailers or B doubles.

Semis are connected by the fifth wheel, and are therefore roll-coupled. "A truck and trailer will tend to roll together," says Loose. "There is a link, so stability system on one of those units will help understand what’s going on with the other unit.

"With drawbar units though, between a dog trailer and a rigid or another trailer, they’re not roll-coupled, so one can roll independently of the other."

Loose adds that there are lots of different warning signs that there’s a brake compatibility problem, for example uneven brake wear; different brake temperatures; and wear on the kingpin.

Solid foundations

Chris Loose says fleets should try and standardise their brake technologies, because they are often mixing and matching trucks and trailers.

That advice applies both to the electronic overlay systems as well as the foundation brake systems themselves.

Re foundation brakes: "If you have got disc brakes on the truck, put disc brakes on the trailer. Get the foundations to match. It just makes life easier."

While on the subject of foundation brakes, the ATA has just released a 15-page technical advisory procedure on slack adjuster setup and compliance to the new National Heavy Vehicle Inspection Manual.

Meanwhile in May the ATA released the second edition of its 24-page technical advisory on ESC and the similar RSC (roll stability control).

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ATA discusses electronic braking technologies

Steve Skinner, Australasian Transport News (ATN)  /  October 17, 2016

Electronic braking systems are now generally regarded as a great thing, but there can be problems if truck and trailer systems aren’t properly matched

Chris Loose is a pretty funny bloke for a truck engineer.

His definition of a truck driver is someone who transports stuff you can’t. And an engineer is an organism who solves a problem you didn’t know you had in a way you don’t understand.

And everybody can relate to what he calls the "bum-ometer".

"The bum-ometer is no longer calibrated to the road," laments Loose, senior engineering advisor with the Australian Trucking Association.

"The trucks now have air suspension seats, they have air suspended cabs, they’ve got huge taper leaf springs and air bag suspension.

"The driver is no longer connected to the road so he no longer feels it.

"The driver is becoming more and more remote from his vehicle and the feel of the road.

"He is inherently as a result driving harder and faster through potholes because he no longer feels them, and it’s a huge issue.

"Unfortunately guys, it’s a male problem, testosterone, we want to get there faster."

And for Loose that’s one of the reasons why electronic roll stability is such an important thing.

Roll stability is part and parcel of the electronic braking systems (EBS) that have become more common in recent years.

Loose gave an entertaining  rundown on electronic braking and stability technology at this year’s Comvec technical conference in Melbourne, organised by Heavy Vehicle Industry Australia.

Life saver

As far as the ATA is concerned, the jury is no longer out on electronic stability control (ESC): it’s a great and proven life-saving technology.

ESC automatically slows the vehicle down via both the throttle and brakes if it senses the risk of a rollover.

The ATA points to a Monash University Accident Research Centre study from a couple of years ago which concluded that mandated ESC in heavy vehicles could reduce fatal heavy vehicle crashes by 4 per cent.

In turn, ESC can be the foundation technology for the even more advanced Autonomous Emergency Braking Systems (AEBS) that we’ve heard so much about for both cars and trucks in recent years.

Monash estimates mandated AEBS could prevent up to an incredible 25 per cent of fatal heavy vehicle crashes.

Meanwhile the Victorian Government says log truck and trailer rollovers have been virtually eliminated thanks to stability control on B-doubles in key logging areas of that state. That’s from an average of 40 rollovers a year previously.

The ATA is advocating that for most applications, electronic stability control should be compulsory in all new truck and trailer models from 2019.

As things stand, the lesser technology of ABS – anti-lock braking – is mandatory on all new trucks and trailers.

This is under the Australian Design Rules 35/04 (trucks) and ADR 38/04 (trailers, with load sensing valves as an alternative.) 

Loose doesn’t agree with it, but dollies are exempt from ABS or load sensing valves. However "through" power must be provided to the following trailer.

In the US and Europe most trailers have ABS; here most trailers don’t.

Ironically, there may be a safety problem with the latest technology, if there is incompatibility between truck and trailer braking systems.

If the truck has a "smart" brake system with ABS and better still EBS as well, and the trailer or trailers are "dumb", that can create a safety issue in itself.

The most obvious example is stamping on the brakes in an emergency: the trailers may not stop as well as the truck, thereby risking a jack-knife situation.

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So typical! Some of us remember when Freightliner first installed ABS. The road salt corroded the electrical connections,and created many jackknife involved accidents! The lawsuits continued long after ABS became a valid safety feature! There is always a " learning curve" with any new technology. In the 80's, there were doubles with converters that had the 60's era air-operated spring-less locking systems while the trucks and trailers had spring type "maxis".

Drivers warned against electronic braking complacency

Steve Skinner, Australasian Transport News (ATN)  /  October 19, 2016

Some are pushing trucks fitted with electronic stability control to the limit, experts say

The experts say that electronic braking and stability technologies are about control, rather than absolute stopping distances.

They say the technologies are great for already-safe drivers who might encounter a sudden emergency situation, and of course there are plenty of those possibilities with idiot car drivers alone.

However advocates of electronic braking acknowledge there is a risk that drivers will become complacent and push the envelope, thinking the technology will save their bacon if they go too hard.

"It’s the guy behind the wheel 9 times out of 10 who controls the destiny of the vehicle, not the technology," says the Australian Trucking Association’s Chris Loose.

"And what we are tending to find is there is a small group of guys who will drive to the limit of the technology. So by having the technology, it’s fantastic, but physics is physics, it will not save them all the time, we still have to ensure that they have the skills."

Isuzu’s Romesh Rodrigo joined Loose in also warning about driver complacency at this year’s Comvec technical conference in Melbourne.

Rodrigo says drivers need education in the new electronic wizardry. He says while in some applications  there have been less rollovers with stability control, there’s also been more wheel end damage.

"The drivers are now just driving to the limit, pushing these vehicles, and there’s a light flashing there but ‘Oh, gee, my truck hasn’t rolled over yet, so that’s a great thing’," says Rodrigo.

"But we’re not teaching the drivers that if that light is flashing, if that (ESC) plug falls out, that truck will be on its side."

Have patience with electronic brake suppliers: ATA

Steve Skinner, Australasian Transport News (ATN)  /  October 20, 2016

Trucking body warns that operators should not tamper with electronic braking and safety systems

Truck owners are being warned to spare a thought for electronic braking and stability suppliers and not to muck around with the technologies.

This includes changing configurations, for example.

"We’re a market of fiddlers, we like playing with things, we like tampering, we all think we can do better," says the Australian Trucking Association’s Chris Loose.

"But if there is an issue, go see an expert."

The ATA’s senior engineering advisor was speaking at this year’s Comvec technical conference in Melbourne, organised by Heavy Vehicle Industry Australia.

It was in the context of a draft guide, yet to be released, on maximising the compatibility of braking and roll stability systems between trucks and trailers.

"This guide is only one level," Loose says.

"The second level is where you need the Knorrs, the Wabcos, the Haldexes, the BPWs, and all those other guys to step up and look at the combinations."

Loose also advises having patience with these electronic systems suppliers, because they have a tougher job in Australia than probably anywhere else in the developed world.

For one thing, the incompatibility problem is going to be around for many years to come because of the slow turnover in trucks and trailers.

"It’s not going to be easy to solve because our fleet age is getting older. It’s 11 ½ years for prime movers."

As we constantly hear, Australia is a unique market, taking a mis-match of technologies  from all over the place.

"We are going to have to build up an experience base that doesn’t exist anywhere else in the world," says Loose.

"We have got trucks from Europe, we have got trucks from America, we have got trucks from Japan and we have got our own home grown stuff; and we’re doing combinations that are longer and heavier.

"Everything is going against them, and we are trying to do something fairly unique in this marketplace, so compatibility is not going to go away, and the guys on the ground servicing these units are going to struggle.

"They’re seeing stuff that is not being seen in Europe, they’re doing stuff that’s not being done in North America, so it’s not easy, so bear with them, help them, communicate with them."

Have confidence

Despite the warning against tampering, Loose says most truck workshops are capable of routine servicing of electronic systems, with technology supplied by the OEMs (original equipment manufacturers).

"And the key thing with any of this technology is regular service," he adds. "Seems simple, but it’s amazing the number of people that won’t actually go and check their wheel end sensors.

"In particular if you’re running off road, those sensors are one of the most exposed items on the vehicle, so they will get caught, sticks will hit them, the electrical lines will be crimped, all that sort of stuff will happen and they do need regular check-ups. So after a long trip, make sure the sensors are checked.

"This technology is great, but if you’re operating off road, if you’re operating remotely, you will have higher operating costs, there’s no doubt about it, but there are benefits too."

Whether it’s foundation or electronic braking systems: "It seems obvious, but it doesn’t always happen, and that’s making sure that equivalent safety critical service parts are used, and this has happened time and time again, bottom line wins out."

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Optimising brake performance explored at TMC 2016

Prime Mover Magazine  /  October 26, 2016

Industry experts have given visitors at this year's ATA-ARTSA Technical & Maintenance Conference (TMC 2016) in Melbourne, valuable best practice methods into managing brake system maintenance and compliance.

One of the most significant sessions came on the event’s first day with Bob Woodward – Project Manager at New South Wales-based Ron Finemore Transport – who joined representatives from transport equipment providers, SAF-Holland, Haldex and BPW Transpec, to discuss achieving brake compatibility and getting the best performance from braking setup.

As part of his presentation, Woodward dispelled the notion that achieving compatibility is anything less than operating within constraints, until a performance compromise can be reached. He also explained that the Australian Design Rules (ADR) have 'tram tracks' of compatibility, with brake performance lying between two, upper and lower guidelines, considered 'compatible'.

Meanwhile, Ian Thomson, Engineering Manager at BPW Transpec, pointed to the myriad factors affecting the development of brake compatibility regulation – in order to cover the whole spectrum of conditions and systems guidelines must account for both disc and drum foundation brakes in several brands, differing type sizes and use in singles, B-doubles and other truck configurations as well as booster and slack adjuster settings.

“Australia presents a particular challenge – not only is its fleet of prime movers sourced from all over – Europe, the US, Japan and Australia, it is also in serious need of an update, with an average age of 11.5 years,” he noted.

When it comes to ensuring your fleet is compliant, both with legal requirements and safety regulations, Thomson recommended that keeping a conversation going with an expert on the type of brakes used. “Even if you’re just changing the tire size, you need to redo your calculations,” he noted. “A miscalculation could result in an accident, so fleet owners should approach the manufacturer of the brakes or a dedicated brakes consultant.”

Thomson also referred to the Australian Trucking Association's (ATA) recently released Technical Advisory Procedure (TAP) as an ideal guide for effective brake adjuster set up, since it can help fleet owners with maintenance and compliance.

Developed in partnership with the ATA, Australian Road Transport Suppliers' Association (ARTSA), Truck Industry Council (TIC), the Commercial Vehicle Industry Association of Australia (CVIAA), the Heavy Vehicle Industry Australia (HVIA) and the Australian Livestock and Rural Transporters Association (ALRTA), the TAP can be a valuable tool for identifying compatibility and ensuring safe practice protocols are followed, according to Thomson.

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