Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Self-Powered Trailers Promise Leaner Freight Runs

spectrum.ieee.org

Post reply on HN
Print view View original

51–60 of 73 posts

Re: Self-Powered Trailers Promise Leaner Freight Runs

#51

Post by ErroneousBosh »

_blk wrote: post #10
WindyTree wrote: post #4

In the US, commercial trailers are used like these crappy sheds, you go get one and the ABS unit is gone, the only thing worth stealing. For any company where this doesn’t hold it’s a big deal. The bigger deal is really RV trailers. You power assist, with simple motors controlled by pulling, and you can pull a huge one with ANY car, you don’t need truck, just modified mirrors. Plus the RV trailer benefits from slow s…

In practice it's of course not so simple. Every truck that passes you (or that you pass) will suck you right in if your tow vehicle isn't heavy enough or you don't have good enough grip. Also, (RV/drum) trailer brakes suck so hard that you really want a vehicle with some additional stopping power other than regular brakes (heavy duty transmission, big engine, and diesel exhaust or compression brake). E-brakes work we…

> Every truck that passes you (or that you pass) will suck you right in if your tow vehicle isn't heavy enough or you don't have good enough grip

You'd think you'd ever see some evidence of this happening and right now at the height of Tourist Season you'd expect to see the roads littered with smashed caravans, but no - it does not appear to happen.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#52

Post by bluGill »

shrubble wrote: post #40

The placement of the Krone pack in the photo at link, makes me laugh: it would never survive in the USA, given the way truck drivers drive and the bumps and curbs etc. that trucks drive over. It would be ripped off or at least heavily damaged within 50K miles.

Maybe some truck drivers. However there are also a lot of trailers in the US that hang even lower than this appears to. The most common situation is trailers have a lot of space between the floor and the ground - so a forklift can drive all the way in. However some trailers - those used for house moving for example - have much lower floors. They have more space inside which is good for lighter things you are putting on the trailer by hand.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#53

Post by bluGill »

ErroneousBosh wrote: post #48
WindyTree wrote: post #4

In the US, commercial trailers are used like these crappy sheds, you go get one and the ABS unit is gone, the only thing worth stealing. For any company where this doesn’t hold it’s a big deal. The bigger deal is really RV trailers. You power assist, with simple motors controlled by pulling, and you can pull a huge one with ANY car, you don’t need truck, just modified mirrors. Plus the RV trailer benefits from slow s…

> and you can pull a huge one with ANY car, you don’t need truck, just modified mirrors So pretty much like everywhere outside the US? Here in the UK it's not uncommon to pull a 1500kg caravan with a bog standard Ford Focus, without any problems at all, and well over two tonnes on a twin-axle one with something like a Volvo V60. People come from all over Europe to holiday here with their caravans, and are towing them…

Those are small trailers that you can pull with small cars in the US. The US has many RVs that need much larger trucks to pull them as well. I don't have much autobahn experience, but I don't recall ever seeing a RV type trailer like are somewhat common in the US.

Even if your car can pull the trailer, that doesn't mean you should. If the trailer is oversized the car and engine can pull it - but you need something much bigger/heaver to control the load if anything goes wrong. More than one person has had their car roll because they were towing a large trailer at high speed and a wind gust pushed them into the ditch. If they were towing at city street speeds they would have been okay, but not autobahn speeds.

You don't need a 7.5 tonner to pull a small trailer. However you do need to carefully check the tow rating, bad things happen if the tow vehicle is too small. You do need a 7.5 tonner to pull a large trailer though.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#54

Post by bluGill »

ErroneousBosh wrote: post #51
_blk wrote: post #10

Earlier quoted context omitted.

In practice it's of course not so simple. Every truck that passes you (or that you pass) will suck you right in if your tow vehicle isn't heavy enough or you don't have good enough grip. Also, (RV/drum) trailer brakes suck so hard that you really want a vehicle with some additional stopping power other than regular brakes (heavy duty transmission, big engine, and diesel exhaust or compression brake). E-brakes work we…

> Every truck that passes you (or that you pass) will suck you right in if your tow vehicle isn't heavy enough or you don't have good enough grip You'd think you'd ever see some evidence of this happening and right now at the height of Tourist Season you'd expect to see the roads littered with smashed caravans, but no - it does not appear to happen.

It has happened people I personally know. It wasn't just a truck passing, it was a truck passing with a good cross wind, which is why it isn't common. This wasn't a small tow vehicle, it was a F350 which is a large truck even by US standards, and it has a heavy duty frame. At least the truck was strong/heavy enough to say out of the ditch and could safely be moved to the side of the road unlike if it was a smaller tow vehicle.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#55

Post by mapt »

Dreami wrote: post #20
crote wrote: post #15

Earlier quoted context omitted.

But that's the thing: you already have to pay a driver to sit around! In Europe there's (simplified) a mandatory 45-minute rest break after 4.5 hours of driving. Similarly, there's a mandatory 11-hour rest period after the daily maximum of 10 hours of driving. And it is very strictly enforced, with every commercial truck having been equipped with a sealed and certified data logger, plenty of random checks by traffic…

At least from the truckers I watch on YouTube from Germany, there is already a shortage of rest stops for trucks. Sometimes you can see them even in the entrance of the rest stops, parked in a dangerous spot. If they all have to charge, then that becomes a problem, because they can’t find a space even „creatively“. Not saying that electric trucks are bad, just one more problem to solve

So build them stops.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#56

Post by mapt »

SonOfLilit wrote: post #30
crote wrote: post #15

Earlier quoted context omitted.

But that's the thing: you already have to pay a driver to sit around! In Europe there's (simplified) a mandatory 45-minute rest break after 4.5 hours of driving. Similarly, there's a mandatory 11-hour rest period after the daily maximum of 10 hours of driving. And it is very strictly enforced, with every commercial truck having been equipped with a sealed and certified data logger, plenty of random checks by traffic…

I think many long-haul truckers work in pairs for this reason?

Regulations are a bit different, not just on what counts as rest, but on physical format.

The normal US front-engine is rare in Europe.

The US extended sleeper generally doesn't exist in Europe

The European compact cabover generally doesn't exist in the US.

The scale influences this more than a little bit. The longest drives you'd find it sensible to make hauling freight inside Europe are between 12 and 18 hours of nonstop travel, while in the US they're more like 40-60 hours.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#57

Post by bluGill »

jimnotgym wrote: post #41
just_some_user wrote: post #7

Cool, but I don’t see the real benefit. Electronic trucks already work quite well, start at around 150k (vs. 150k for a retrofitted e trailer), and are afaik mostly limited by the charging infrastructure. If you now add a an electronic trailer to your diesel truck, you now also have to care about charging. Yes, in Europe the legally required rest periods can already be used for efficient charging, but this is not an…

I suppose the trailer has a lot of space for solar panels on top, which the tractor does not. But those could be connected to the tractor rather than the trailer. Of course

Last time I ran the numbers, in ideal situations a truck/trailer could generate enough power from solar alone to drive on the highway. Ideal means the truck is already at speed, it is towing multiple trailers (length is only legal in a few states), they are used the most efficient solar panels made (significantly better than the mass produced panels most people are putting on their house - at a massive increase in cost), it is near noon, and it is near the equator.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#58

Post by nradov »

ErroneousBosh wrote: post #48
WindyTree wrote: post #4

In the US, commercial trailers are used like these crappy sheds, you go get one and the ABS unit is gone, the only thing worth stealing. For any company where this doesn’t hold it’s a big deal. The bigger deal is really RV trailers. You power assist, with simple motors controlled by pulling, and you can pull a huge one with ANY car, you don’t need truck, just modified mirrors. Plus the RV trailer benefits from slow s…

> and you can pull a huge one with ANY car, you don’t need truck, just modified mirrors So pretty much like everywhere outside the US? Here in the UK it's not uncommon to pull a 1500kg caravan with a bog standard Ford Focus, without any problems at all, and well over two tonnes on a twin-axle one with something like a Volvo V60. People come from all over Europe to holiday here with their caravans, and are towing them…

European caravan trailers are generally designed with a much lower tongue weight, like only 4%. This reduces strain on the tow vehicle at the cost of reduced stability. It is ridiculously dangerous to tow such a trailer at full "Autobahn speeds". You might be able to get away with it on a straight road if nothing goes wrong but a sudden maneuver or even a strong gust of wind can lead to uncontrolled oscillation and a roll-over crash.

https://www.theautopian.com/heres-the-physics-behind-tongue-...

US trailers are generally designed with something like 10-15% tongue weight which allows for much higher dynamic stability but also requires a much stronger tow vehicle. As usual there is no free lunch in mechanical engineering.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#59

Post by bluGill »

inigyou wrote: post #17
wodenokoto wrote: post #12

Earlier quoted context omitted.

Maybe you shouldn’t throw out your new trailer, but it looks like a good deal for expanding a fleet. Remember that all signs point towards more CO2 fees and higher gas prices in the coming years

I'm not seeing any sign of CO2 fees increasing in the USA. If anything, they'll be federally outlawed.

Not in the next 3 year. However there are more elections coming up. And other things changing. For that matter even if the US does nothing, other countries doing something will forced changes. Petro cars are so cheap in the US (they are not exactly cheap) in large part because the design costs are amortized over so many buyers, when the rest of the world isn't buying them that drives up costs in the US.

Meanwhile I'm not the only US driver who has discovered how much cheaper a EV is, so even without CO2 fees things are changing - just slowly.

Re: Self-Powered Trailers Promise Leaner Freight Runs

#60

Post by nradov »

reactordev wrote: post #33
SonOfLilit wrote: post #30

Earlier quoted context omitted.

I think many long-haul truckers work in pairs for this reason?

And split the revenue? No way Jose. Team driving is not preferred.

What are you talking about? All of the major long-haul trucking companies hire team drivers.

https://schneiderjobs.com/truck-driving-jobs/driving-opportu...

Post reply on HN