Segway, GM Partner On Two-Wheeled Electric Car 394
Slartibartfast was one of many readers sending in news of GM's partnership with Segway to develop a two-seater urban electric vehicle. It's called the Personal Urban Mobility and Accessibility, or "PUMA." This is just a prototype, so don't get your credit card out yet. Its total cost of ownership could be about 1/4 that of a traditional car, GM says. The prototype runs for 35 miles, at a top speed of 35 mph, on lithium-ion batteries. It features the now-familiar Segway balancing technology, though fore-and-aft training wheels are visible on the prototype. Some commentators have likened it to a high-tech rickshaw, others to a golf cart. Engadget describes how the ride feels.
Campus life... (Score:1, Interesting)
Just imagine the convenience of having a two wheeled, compact and light weight form of transportation that you could lock up on your way into class.
Re:Yeah, but what's the point? (Score:3, Interesting)
Or add two more wheels, a couple more seats, a larger engine, and enclose it so you're better protected at higher speeds...
Obviously this is just GM wasting more (of my) money. A cell phone acting as the dashboard? Some proprietary wireless communication between pumas? Destined to fail.
Re:Seems rather silly (Score:3, Interesting)
He quickly changed the subject.
Re:Yeah, but what's the point? (Score:3, Interesting)
oops - not the 3 times part. Not close - but that Germany is ahead of China at all is surprising and impressive to me.
Re:Yeah, but what's the point? (Score:4, Interesting)
I'm pretty sure that this information is false. Let me see...yeah, here we go [straightdope.com]:
Groundbreaking research in bicycle dynamics was published in 1970 by David Jones. He mounted counter-rotating gyroscopes on bikes to counteract the gyroscopic effect of the wheels. The resulting bikes were quite rideable. So why do bikes stay up?
The answer is: trail. Trail is the difference between where the bike's front wheel contacts the ground and where the steering axis (drawn through the fork of the front wheel) meets the ground. Well-designed bicycles have negative trail--that is, the wheel contacts the ground behind where the steering axis meets the ground. When you tilt, the trail causes the wheel to turn, thus converting the tilting motion into a turning motion, etc., as per my original report. The acid test done by Dr. Jones is in creating bikes with positive trail. Even professional cyclists can't ride those very far.
Re:Yeah, but what's the point? (Score:5, Interesting)
Their weather (if you can call it that) is just a wee bit different as well. One of those little SMART cars would be the dumbest choice you could make for winter driving here.
My friend has a smart. My boss has a mini. We live in sunny Montreal. Here we hit 30 degrees in summer and -30 in winter. That's a 60 degree c swing yearly and in 2007-2008, we had 3 (three) meters of snowfall. In winter they put on winter tires and driver very comfortably through snow. Moreover, my boss had a jeep explorer beforehand, and he had a harder time driving it on ice than the mini.
I think countries like Norway may actually know what snow is, ice and black ice are. I understand that from an intuitive point of view, it looks weird as it seems natural that a hummer with huge tires would get a better grip on the street than a dinky little car, but the issue of sliding is more a question of friction, and these car were designed to grip the road. Their wheels are placed "SMART"ly and the weight is "SMART"ly distributed.
Re:Yeah, but what's the point? (Score:3, Interesting)
The conservation of angular momentum does not play a role in keeping a normal bicycle upright.
Yes, gyroscopic effects exist. They affect keeping your bike upright the same way finding change on the street affects your income: Not enough to be mentioned in a reasonable discussion.
I'm trying to avoid sounding like an ass, and probably not doing a very good job, sorry. Incredibly persistent erroneous memes like this get under my skin.
Re:Yeah, but what's the point? (Score:3, Interesting)
Two front wheels and one rear wheel = understeer. The other way around = oversteer. The former is generally considered to be safer.
The center of gravity is also a big concern. The reason those three-wheeled ATV's that vlm mentioned above were a problem was that they were top heavy and the engine was too far forward. If they'd put the engine a bit aft of the rear wheels and made it a flat configuration they'd have been much more stable.
Re:Yeah, but what's the point? (Score:3, Interesting)
Re:Yeah, but what's the point? (Score:2, Interesting)
From what I can tell Smart tries too hard to be all things and fails.
They wanted to be cheap, so they used steel, they wanted to be safe, so they used lots of it, they wanted to be high mileage, but lots of steel kills that.
And somehow they aren't that cheap either.
Compare a Yaris-S 3-door to a Smart Passion Coupe.
Same price essentially, Smart gets 33/41 MPG to the Yaris's 29/35.
Unless you are in a situation where parking by driving towards the curb is a HUGE benefit, the Yaris is almost certainly a better deal.
Thar Smart needs to drop 3K from the price, or get it's mileage past 45 MPG. Especially if Diesel starts to take-off.