How the Prius wastes fuel

[oldtamiyaphile]

Originally Posted by Natalya

And then once I'm there I do what I can to keep the car rolling instead of stop-and-go because, obviously, MPGs, and maybe (wildest dreams here) I can train the driver behind me to not be such a nut and see that stop-and-go could just be slow-coasting.

Yeah, I wonder if anyone's had an AHAH! moment when I do that. I do very occasionally see someone doing the same thing (once that I can remember).

[Frank Lee]

That would require situational awareness AND introspection!!!

[Xist]

So, how come each lane can have a different speed? It seems like they oscillate with different frequencies.

[niky]

Originally Posted by Natalya

And then once I'm there I do what I can to keep the car rolling instead of stop-and-go because, obviously, MPGs, and maybe (wildest dreams here) I can train the driver behind me to not be such a nut and see that stop-and-go could just be slow-coasting.

So much this.

[elhigh]

Originally Posted by Natalya

I heard (lol how much stupid stuff starts with those two words?) that most stop-and-go on the highway is related to the flow on one section of the highway having a different speed from the next section, and the stop-go is the adjustment between the two speeds.

There's a portion of my commute that, for about a mile, is prone to terrible stop-and-go rippling for exactly the reason you describe. The ripples can propagate as much as another mile or so upstream, it's ridiculous.

Getting into the left lane and pushing up to a higher speed is the strategy at that point. And even so sometimes a ripple can develop there; maintaining a large gap between myself and the next guy can help a lot to mitigate or cancel them out, but there's almost always some fool crowding my bumper, gnawing at his steering wheel because the twerp in the little Honda won't close up that gap.

I can't get my good mileage on that part, but influencing others' behavior and preserving my gap mean not getting hit with the ripple, which would be even worse. I just wish it weren't so stressful, having to resist the peer pressure of the tailgaters who are so dissatisfied that I won't fill the gap.

[Natalya]

Originally Posted by elhigh

I just wish it weren't so stressful, having to resist the peer pressure of the tailgaters who are so dissatisfied that I won't fill the gap.

Moments like that for me every day...

Today I was on the highway and yeah there was 100 feet between me and the car in front, but I knew he was gonna hit the brakes so I didn't accel up into him and the guy behind me was like tailgating... So stupid.

I just want to be like, "Yeah drive up there as fast as possible so you can slam your brakes even harder!!" It can be frustrating. People just want to race into the stopped traffic at full force.

****

Oh gosh, this is slightly unrelated, but later today I was driving with my windows down. Know what's more scary than being tailgated? Being tailgated by a crazy woman who is yelling into her cell phone!! I was so paranoid she was going to rear-end me in her fit of rage at whoever was on the receiving end. I have a full-assist brake switch and LED brake lights, every time I was approaching a stop I toggled my brake switch real fast a few times to warn her to pay attention to the road not the sorry sap on the other end of her phone.

[Hersbird]

Just to be Devil's advocate... if compulsory pulse and glide helps economy, doesn't compulsory tailgating also help econony? Personally I can't wait anymore for a completely autonomous fleet of cars. Driving has always been one of my favorite things and I would argue nothing has in reality given America more freedom then our roads and cars. I just hope there is an effort to maintain the freedom part to go when and where you want for next to nothing with animinity while eliminating the ability to be an ass to everyone else.

[Frank Lee]

If the roads weren't so crowded this wouldn't be much of an issue.

And it's not that there aren't enough roads.

[Natalya]

Originally Posted by Hersbird

Just to be Devil's advocate... if compulsory pulse and glide helps economy, doesn't compulsory tailgating also help econony? Personally I can't wait anymore for a completely autonomous fleet of cars. Driving has always been one of my favorite things and I would argue nothing has in reality given America more freedom then our roads and cars. I just hope there is an effort to maintain the freedom part to go when and where you want for next to nothing with animinity while eliminating the ability to be an ass to everyone else.

Eventually what's going to happen is the NHTSA is going to approve some kind of truck-to-truck communication about vehicle position and speed and hazard detection, and give some limited control to onboard computers on the trucks, allowing trucks to draft eachother semi-autonomously and very safely. This technology will then be made available to passenger cars.

Auto enthusiasts will demand the continued right to drive even as other cars become more automated; what will happen is there will be dedicated lanes on the highway for automated cars only while the rest of us have to use the normal lanes.

I think the compulsory P&G someone else mentioned above was more of a joke... hitting the gas then slamming on the brakes in bumper to bumper traffic like we see on the highways isn't P&G.

[elhigh]

^Reminds me of a story I was trying to write. It was awful and juvenile and I abandoned it, but one idea I touched in it was a convoy - a train really - of connected vehicles. The lead gets crap mileage but all the rest did great, and on average all were pretty good.

With autonomous vehicle control, high precision reactive cruise control and even intervehicle communication, I can see a system of petition-and-permission convoy creating software, vehicles compare each other's destinations and link up - not physically like in my story, lo these many years ago - to form mutually beneficial teams. Such convoys would default to the middle lane if one were available, and automatically open gaps in themselves when approaching exits and entrances if no middle lane was available.

Close up the gap enough and the lead car gets a benefit too. I wouldn't trust a human with this kind of tailgating, I'm talking about a following distance of maybe three feet or less - close enough the two vehicles are aerodynamically coupled.

Sorry, this has wandered away from the original topic. I'll stop here.