Appeal For Commuter GPS Logs To Aid Electric Cars 144
holy_calamity writes "A team at Carnegie Mellon University has begun a project seeking to design a kit to cheaply convert secondhand cars into cheap, electric ones suitable for commuting, if little else. They hope to rely heavily on smart management software to extract as much efficiency as possible from regenerative braking, and knowledge of terrain from GPS tracking. But they are hampered by a lack of public data on how commuters actually drive. Their solution is to appeal to GPS users to upload .gpx log files of their commute to the team's site. The data is plugged into a simulator that reveals how much cheaper an electric car could do your journey, and an anonymized public dataset will be created. A programming contest will award a production electric car to the coder who designs the best management algorithm using it."
Good in theory (Score:1, Interesting)
In theory, this is a good idea, but I do not think it will work that way. I have yet to see a specialized, 35+ mph, 10+ year lifespan (important for resale value) car that will cost under $10K. A basic, 30+ mpg car can be had under $12K. A basic plug in hybrid (Prius?) will likely go under $25K (without extra batteries), and get pretty good mileage as is.
I expect in the near future, there will be plug in hybrids with a variable amount of batteries. People will go to a car dealer and buy (or rent) the plug in hybrid without range extending batteries. They will drive around and see how many kwh they use up. Based on that, the buyer will buy the amount of kwh in batteries they feel they need. If they drive long distances, the buyer may skip the the plug in hybrid altogether and buy a diesel instead.
I think the average public's intelligence is being underestimated when it comes for the potential to save money.
Slightly related, open source electric cars (Score:3, Interesting)
I've been following the progress of a Finnish electric car project:
Quote:
"we are offering the open source blueprints of the electric conversion kits globally and leave the manufacturing of the kits to the markets"
http://www.sahkoautot.fi/eng [sahkoautot.fi]
http://ecars-now.wikidot.com/ [wikidot.com]
Re:Braking (Score:5, Interesting)
What do you mean sacrifice power? The prius' regenerative braking already has this kind of effect. It doesn't completely eliminate pad wear, but it fantastically extends the life of the pads. There are ones out there with over 100k miles still using the factory pads.
Re:Anonymized Travel Data (Score:4, Interesting)
So someone who's more in-the-know with anonymizing data sets of this or similar nature able to shed some light on this?
Much like social networking sites, the best solution is not to upload anything you don't want your name on. Since they're trying to build a "commuter car" as opposed to a "adult video shopping excursion car", the best solution is to only upload the drive to and from work, unless your work happens to be "professional adult video shopper".
Re:Braking (Score:3, Interesting)
Re:Braking (Score:2, Interesting)
The friction brakes on my Tesla still squeak after 12,000 miles of driving.
I find the brakes on my Tesla Roadster also squeak - mostly due to non-use. The brake dust gathers on the rotor and doesn't get wiped away since I mostly use regen to slow the car. This causes the brakes to squeak when I do try and use them. When this happens, I can make the squeak go away by braking hard once to remove the brake dust. I find an empty residential street and bring the car up to 15 or 20 miles per hour, and then stomp hard on the brakes to come to a complete stop. No more squeak for another 1000 miles.
Re:My experience (Score:3, Interesting)
I love the people who tailgate using boolean throttle techniques; they constantly alternate between slamming on the accelerator then the brakes to maintain a constant average speed. It's only slightly better than driving at a constant speed while simultaneously applying the brakes and the accelerator but it clearly projects to drivers around them that they're morons...which I assume is the idea because I can think of no other reason why they do it.
I think every new car should have a system that calculates how much fuel you consume and compares it against how much you should have consumed for the same distance and average speed if you were driving optimally. It could then use current gas prices to give you an output in dollars wasted. You could think of it as an idiot tax for poor drivers.
Requires Cheap Batteries First (Score:5, Interesting)
According to http://www.sahkoautot.fi/eng:faq#toc3 [sahkoautot.fi], lithium batteries will last for about 125,000 miles. What nobody wants to talk about is the price of replacing them. They just want to talk about how "cheap" it is to charge them. Articles just assume that by the time you need to replace them, surely cheaper and better batteries will be available. I've heard estimates of about $10,000 for replacing the batteries in an electric vehicle. So that's 8 cents per mile times 30 miles per gallon that conventional engines get for the same size vehicle which is $2.40. So pretty much zero savings.
My Versa gets around 36mpg which bumps the cost per gallon of the electric up to $2.88 which is about 30 cents more than fuel in my area. And that doesn't include the cost of electricity needed to charge the batteries.
Electric cars simply cannot beat the economics of a small commuter car. Until they get the price and performance of rechargeable batteries well below the cost of regular gas there's no financial incentive to buy an electric car. They need to do far better than 8 cents per mile for electric. I'm not going to spend $20,000+ on a car just to have electric when I'm saving no money per mile and could have spent $10,000 less on standard car AND saved money on getting where I want to go.
Re:Braking (Score:3, Interesting)
Think slamming it in reverse at full throttle instantaneously, up to and including breaking the tires loose and smoking them. With current technology (electric "current" get it?) that would probably roast the controller and the motor.
Current regenerative braking systems are far more advanced than this.
Today's electric cars use AC induction motors driven by variable frequency inverters. Throttling the motor from acceleration to deceleration is done by varying the motor's drive frequency from slightly higher then the motor's speed (positive slip) to slightly lower (negative slip). This speed/frequency difference can be controlled very precisely, thereby controlling the amount of torque and power into or out of the motor. So, like acceleration, braking and regeneration can be easily modulated. Nothing gets 'slammed' in either direction.