4 ms·

No, because the weight is the cargo. As more and more semi-truck trailer beds transition to aluminum floor joists, for weight reduction, it's an overall increas

No, because the weight is the cargo. As more and more semi-truck trailer beds transition to aluminum floor joists, for weight reduction, it's an overall increase in productivity because the truck can now haul more cargo weight.

dredmorbius 9y ago
TBF, I suspect GP is referring to reducing the gross weight of trucks (vehicle + load), rather than the net of the vehicle alone. That's possible too, but would be tremendously less efficient as you'd have the same air resistence (or at least a substantial amount) but without the same cargo capacity. Railroads tend not to develop potholes.
- NamTaf 9y ago
  You can't really reduce the net weight whilst carrying gross weight beyond a point because the structure won't cope with holding the cargo. Maybe you can optimise some of it out but whether a human presses pedals/turns wheels or a computer does is relatively immaterial towards the net weight of the vehicle structure. Autonomy won't play a big role in that compared with improved design and materials. Also, remember that roads aren't made out of head-hardened solid steel - if they were, they'd probably nearly forever. Rail itself may not get quickly damaged (though they do) however rail wheels, which are made of relatively softer metal, develop all kinds of damage, require the machining away of the damaged surface periodically (as in, wheels shrink over time as mateiral is cut off it to get to new metal below) and only last a matter of years for heavy haul environments: http://www.asa.transport.nsw.gov.au/sites/default/files/asa/railcorp-legacy/disciplines/rollingstock/esr-0330.pdf http://www.asa.transport.nsw.gov.au/sites/default/files/asa/... Search for spalling, shelling and rolling contact fatigue as examples.
- B1FF_PSUVM 9y ago
  It would be fuel vs. road cost ... (There might be a paper in figuring out the sweet spot given hypothetical costs ...)
xioxox 9y ago
However, road damage doesn't scale with the weight. The damage roughly scales like the weight per axle to the power four! e.g. http://www.pavementinteractive.org/equivalent-single-axle-load/ http://www.pavementinteractive.org/equivalent-single-axle-lo...
- B1FF_PSUVM 9y ago
  I figured it would be a power, was just hand-waving with "steeply progressive" ;-)

dredmorbius 9y ago

TBF, I suspect GP is referring to reducing the gross weight of trucks (vehicle + load), rather than the net of the vehicle alone. That's possible too, but would be tremendously less efficient as you'd have the same air resistence (or at least a substantial amount) but without the same cargo capacity. Railroads tend not to develop potholes.

NamTaf 9y ago
You can't really reduce the net weight whilst carrying gross weight beyond a point because the structure won't cope with holding the cargo. Maybe you can optimise some of it out but whether a human presses pedals/turns wheels or a computer does is relatively immaterial towards the net weight of the vehicle structure. Autonomy won't play a big role in that compared with improved design and materials. Also, remember that roads aren't made out of head-hardened solid steel - if they were, they'd probably nearly forever. Rail itself may not get quickly damaged (though they do) however rail wheels, which are made of relatively softer metal, develop all kinds of damage, require the machining away of the damaged surface periodically (as in, wheels shrink over time as mateiral is cut off it to get to new metal below) and only last a matter of years for heavy haul environments: http://www.asa.transport.nsw.gov.au/sites/default/files/asa/railcorp-legacy/disciplines/rollingstock/esr-0330.pdf http://www.asa.transport.nsw.gov.au/sites/default/files/asa/... Search for spalling, shelling and rolling contact fatigue as examples.
B1FF_PSUVM 9y ago
It would be fuel vs. road cost ... (There might be a paper in figuring out the sweet spot given hypothetical costs ...)

xioxox 9y ago

However, road damage doesn't scale with the weight. The damage roughly scales like the weight per axle to the power four! e.g. http://www.pavementinteractive.org/equivalent-single-axle-load/ http://www.pavementinteractive.org/equivalent-single-axle-lo...

B1FF_PSUVM 9y ago
I figured it would be a power, was just hand-waving with "steeply progressive" ;-)