What hasn't been brought up is that very few trucks of one company are going for any appreciable distance on the same route. Think of how many trucks you may see on I-80 (Ohio Turnpike) and then break them down by company. There are only a few of the biggest companies find it worthwhile to use Turnpike doubles (2x53) or triples (3x28). Also, a large percentage of trucks don't spend a lot of time on the Interstates. You are taught to take the most direct route, not always the fastest. Miles on equipment costs money.
I used to drive for a Top 10 carrier who wouldn't pay for turnpike tolls unless it was a plate glass or other fragile load. I've driven across the entire state of Ohio on US30, back when it was all two lane.
Murphy Siding? If there's a human being in each cab, what have you saved? Why not let that person just drive the truck?
Mhch of the problem with truck operation on 'mixed-traffic' roadways is in the exaggerated following distance and slow recovery acceleration when trucks are distributed across lanes; it is reasonably unsafe to 'draft' at effective aerodynamic following distance for a variety of reaction-time and foreground-attention reasons. Platooning reduces these, if done right almost to the point of practical elimination; when you add predictive cruise to hold the engine (on a combustion-engined Class 8 tractor) reasonably in its power-band "automatically" with few 'excursions' and need to recover rotational speed against compression, the advantages become even more worthwhile.
I would add that the ability to run at reasonably constant 'speed limit' speed may have the same benefits for 'precision scheduled trucking' that can be observed in railroading; given the ability to platoon at off-peak times this promises to reduce the need to tolerate truck-induced congestion at many current points (specifically including I-40 and I-81 East of the Mississippi) even net of fixed bottlenecks (there is still a point in the city of Memphis that the most direct I-40 route from west to East gies down to one lane!).
If for some reason we come to tolerate higher speed for 'priority' platoons capable of reliably holding higher speed (with appropriate 'compensation' for the geometrically increased infrastructure wear and damage) you again compress faster and inherently more dangerous traffic into a shorter length of exposure to other traffic, passing in a shorter time. The effective vehicle density of such an operation may in fact converge on the efficiency of TOFC for restricted traffic volume or demand at the kind of higher speed that intermodal customers have traditionally failed to pay for over the years.
None of this, though, brings us to the sweeping 'economies' that were touted for electricity-fairy-powered magic self-driving electric trucks built in adequate numbers for a financeable price. We have a very long way to go to make platooning under robotic control as safe as individual oversight even when the 'autopilot'-type systems do much of the work in servo. I would in fact argue you'll never get there 'enough' not to lose your butt in the first major lawsuit... and you can bet there will be a lot of lawsuits, some probably justified...
Overmod The net result will be no worse than what human truck-driver reactions would be... and remember there is still a human, paying reasonable attention to road conditions, in each cab who can 'take over' as effective platoon leader of any following vehicles by reacting to traffic that the automatics might not accommodate.
Thanks to Chris / CopCarSS for my avatar.
EuclidTherefore, I conclude that for platooning to be safe, no cars can be allowed to enter the gaps between the trucks in a platoon.
The architecture of the V2V used here allows sufficient distance to assure all the 'following' vehicles would slow as commanded, and of course this rate is for any likely preceding emergency stop that cannot be 'avoided'. That is a concern, but it was adequately discussed before 1998 and is well understood by actual designers (rather than constructors of straw hypotheticals) today. (For the sake of completeness you may want to consider this letter and its context
https://transportation.house.gov/imo/media/doc/2020-01-22%20Full%20TI%20Letter%20to%20FCC.pdf
but anyone not born yesterday will recognize this does not concern channel 172 or any interference that might cause loss of integrity on that channel. It's cute to extrapolate current massive-data approaches to autonomous guiding to a requirement to broadcast that data in the ITS bands... but I don't think that is an efficient necessity (and stuff like Qualcomm's cutely-named C-V2X tech, which would use a great deal of the 'released' spectrum, certainly would love to be able to exploit it 'free'...)
The systems of machine vision that assist lanekeeping can be easily fused to detect turn-signal (and in emergencies predicted vehicle trajectory). The net result will be no worse than what human truck-driver reactions would be... and remember there is still a human, paying reasonable attention to road conditions, in each cab who can 'take over' as effective platoon leader of any following vehicles by reacting to traffic that the automatics might not accommodate.
What I expect to see as a MUTCD-compliant solution is 'merge zones' (denoted by stripes and signage) in which trucks break close following to preferentially allow other vehicles right-of-way across the platoon lane. This is in addition to the system of 'truck no-passing zones' that eliminates the current issue with slow passing on four-lane Interstates... probably enforced with cameras and AI/ES logic 'for everyone' that camps out in the passing lane for more than an undue time... but I digress.
Naturally a car in the middle of a platoon breaks close platooning, but not most of the guiding and predictive effects of the system. Assume for a moment the driver is a normal human in a non-ITS-equipped vehicle. He or she will take up what they consider a 'safe' following distance, and the adaptive cruise on the following truck will back the following distance up to 'normal and prudent' as law-abiding and safe drivers do today. Note however that the channel 172 data stream still fixes following guidance at the new longer spacing for the trailing vehicle, and of course any vehickes behind that one will still be able to close-follow.
The situation is more complicated when you have 'slower drivers' in the assigned platoon lane, potentially right down to the 40mph minimum. The ITS enablement allows platooned passing where the permitted speed differential is sufficient, but will restrict following 'safely' otherwise.
This accounts for morons, but not for potential evil intent... the kind of insurance scam you see in Russian dashcam videos, or 'activists' trying to fight trucking 'pollution', perhaps, or just misguided road rage. Again, the default behavior is simply to relax the commanded following distance as long as the delay persists ... then use 'best profile' to recover speed and platoon 'lashup'.
This is not an Infinibus parody situation where big trucks thunder nose to tail past exits while Caspar Milquetoast in his Pacer can't merge in. It's the vehicle equivalent of sensor-fused CBTC, and can be programmed in accord with whatever local motor-vehicle code is amended to advise or require.
Euclid Therefore, I conclude that for platooning to be safe, no cars can be allowed to enter the gaps between the trucks in a platoon. How will that be accomplished? Without that feature of keeping cars out of the platoon, the trucks in the platoon would not be able to follow at the close gap, and yet that close following is the advantage claimed to allow the road to carry more traffic due to automatic trucks running in platoons.
Therefore, I conclude that for platooning to be safe, no cars can be allowed to enter the gaps between the trucks in a platoon. How will that be accomplished? Without that feature of keeping cars out of the platoon, the trucks in the platoon would not be able to follow at the close gap, and yet that close following is the advantage claimed to allow the road to carry more traffic due to automatic trucks running in platoons.
Fully automated passenger vehicles are the only way to do this. (well not ONLY, but the only safe way).
This strikes me as yet another thing to throw into the growing pile that is "automated vehicles only gain their described advantages once the entire operational fleet is automated."
Murphy Siding Since OP never seems too interested in answering questions,
He doesn't get paid for that.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.
ttrraaffiiccHere come the truck platoons!
PLATOON OPERATIONAL QUESTION:
The article mentions that trucks sometimes follow unusually close in order to prevent cars from getting in line between them, and with automated trucks, they can follow even closer together to keep cars out from between them. But what happens if a car driver does enter the short gap made possible by automatic trucks? The car driver won’t know that there is a special reason why two trucks are driving so close together. From the car driver’s point of view, one truck is following too close, and should back off to make room for the car entering the gap between two trucks.
So the car driver will signal intent and begin entering the short gap between the two trucks. When this happens, the automatic system will slow the second truck to let the car driver into the gap.
Then when the car enters the gap, the length of the gap may have to increase by several times because the trucks can no longer follow close as if being one truck made possible by the fact that both trucks are automatically driven. And the addition of the car between the two trucks will force the car to slow in order to increase its gap to the lead truck, while that forces the second truck to slow down and give space to the car.
So, when a car merges into the small gap between automatic trucks in a platoon, it will require significant braking and slowing of the second truck. This will exaggerate the danger to traffic following the second truck. What if this was to happen with a longer platoon of say 20 trucks? What if say 3 drivers decided simultaneously to merge into the platoon of trucks? It seems to me that this could cause a kind of dangerous “slack run-in” similar to what can happen with freight trains.
Any time a car enters the gap between two trucks in a platoon, the car will break the connection of the virtual relationship that makes the two trucks into one truck for practical operation.
Overmod- Since OP never seems too interested in answering questions, maybe you can provide some insight. How do you picture things like this work: A platoon of 2 or more trucks is heading down the interstate between Omaha and Des Moines. That corridor is solid trucks changing lanes taking miles to pass other trucks. How do trucks #2 through #100 do this withour a set of eyes in the cab? How does the platoon handle icy road conditions, or other conditions that would require action form someone in the driver's seat?
Murphy SidingYou didn't even read the article, did you?
It should occur to anyone who thinks about this that there are no restrictions in this system to just 'two' vehicles -- that is just a reasonable test condition. As noted the test volume of actual freight carried so far is minuscule, but that is because it is a test: there needs to be a 'more ubiquitous' use of the various standardized technologies, harmonization of the proprietary ones, and buildout of the GPS/GIS infrastructure the railroads had the opportunity to build out as part of the PTC mandate but dropped the ball on ... I expect the trucking industry to drop the ball, too, but whine successfully for the Government to provide it. (It's related to safety, don'tcha know, and not dissimilar to what is provided with air traffic control...)
What it does nearly immediately is allow a decrease in effective congestion in many places on the Interstate system. It also provides a strong incentive to weed out trucking people who overload beyond their known tractor capacity, or play games with crawling uphill and then coasting past speed limits downhill -- a technique that in fact 'saves fuel' but is intolerable to other highway users.
The operational model is likely to settle on some defined maximum platoon length, and I have argued for many years that the system needs to detect legitimate issues with uninstrumented cars, for example allowing unrestricted emergency 'move to the right' as mandated in many state motor-vehicle codes or facilitating access to exit lanes or entering vehicles in what may be inadequate acceleration lanes -- while remaining resistant to intentional interference. If Peloton has not done this, it would not be particularly difficult to standardize and then implement it.
This only partially leads to 'savings' in the primitive sense ttrraaffiicc uses. But it dramatically opens the highway system to increased utilization both in terms of trucks of various sizes and kinds and individual motor vehicles (presumably including increasing numbers of autonomous vehicles that are ITS enabled). So it is a future of convenience and safety rather than massive "savings" to shippers ... or massive decreases in operating costs to offset the coming cost and regulation increases particularly as governments actually start ensuring trucks pay their true fair share of infrastructure damage and inconvenience they cause, and collecting appropriate 'tolls' instead of the current bureaucratic system of road-use taxation.
I'm not sure that I understand the OP's premise. The biggest trucking companies are investing more and more in domestic intermodal and yet they're making a mistake? I'm sure they know what their business is. That's how they got as big as they are.
Put them on a TRAIN!!!
Caldreamer
ttrraaffiicc https://www.fleetowner.com/technology/autonomous-vehicles/article/21134374/one-driver-two-trucks-paving-the-way-to-public-automation-acceptance Here come the truck platoons! By increasing asset utilization and decreasing fuel consumption and labour costs, platooning is going to be a boon for the trucking industry, but a massive threat to the rail industry. If customers only save 15% compared to trucks with domestic intermodal but they have to deal with the bad customer service of railroads and long transit times, what are they going to do when platooning drops trucking's cost to be at parity or below intermodal? Seems pretty obvious. Railroads don't exactly have a lot of room on pricing either since domestic intermodal is low margin business. It is quite a shame too. A lot of companies invested in new fleets of domestic 53s over the last year or so, especially reefers. Oh well, better luck next time, that is if there is a next time. #intermodalisoverparty
https://www.fleetowner.com/technology/autonomous-vehicles/article/21134374/one-driver-two-trucks-paving-the-way-to-public-automation-acceptance
Here come the truck platoons! By increasing asset utilization and decreasing fuel consumption and labour costs, platooning is going to be a boon for the trucking industry, but a massive threat to the rail industry. If customers only save 15% compared to trucks with domestic intermodal but they have to deal with the bad customer service of railroads and long transit times, what are they going to do when platooning drops trucking's cost to be at parity or below intermodal? Seems pretty obvious. Railroads don't exactly have a lot of room on pricing either since domestic intermodal is low margin business. It is quite a shame too. A lot of companies invested in new fleets of domestic 53s over the last year or so, especially reefers. Oh well, better luck next time, that is if there is a next time.
#intermodalisoverparty
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