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Appeal For Commuter GPS Logs To Aid Electric Cars

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."

26 of 144 comments (clear)

  1. Regenerative breaking? by Shadyman · · Score: 4, Funny

    Is that where they break, and then fix themselves?

    I am Car of Borg. You will be assimilated.

    1. Re:Regenerative breaking? by olsmeister · · Score: 2, Funny

      A variant of ye olde perpetual motion machine.

  2. TomTom by Anonymous Coward · · Score: 2, Informative

    TomTom has been collecting this data for years for their IQ Routes:

        http://www.tomtom.com/page/iq-routes

    Did CMU ask them ?

    1. Re:TomTom by richlv · · Score: 2, Insightful

      exactly. http://www.openstreetmap.org/ project has massive amounts of gpx tracks uploaded from all over the world, and i think that would be a wonderful source of information for these people.

      --
      Rich
  3. My experience by rrohbeck · · Score: 3, Insightful

    From what I see here in rush hour, you only need boolean control: Full throttle or hard braking. When I coast towards a red light, there'll always be someone next to me who steps on it and cuts in front of me.

    1. Re:My experience by Brian+Gordon · · Score: 3, Funny

      Yeah I wrote time travel algorithms for freeway travel in my last job. The queue travel was pretty much directly related to the length of the freeway at the end of time.

    2. Re:My experience by Interoperable · · Score: 2, 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.

      --
      So if this is the future...where's my jet pack?
    3. Re:My experience by Interoperable · · Score: 2, Insightful

      If they got $0 for the sale of the SUV I'd say they deserve a $25K idiot tax.

      --
      So if this is the future...where's my jet pack?
  4. Braking by wildsurf · · Score: 4, Informative

    It's "braking," people. Braking. Though in the case of electric cars, that usually means decelerating/regenerating. The friction brakes on my Tesla still squeak after 12,000 miles of driving.

    --
    Weeks of coding saves hours of planning.
    1. Re:Braking by wildsurf · · Score: 2, Informative

      Michael, you have it actually backwards. Electric cars gain energy by braking without friction. The rotating wheels of the car act as a generator, converting the car's kinetic energy into electricity with about 70% efficiency. That's why the friction brakes on my Tesla still squeak; because the regenerative deceleration is enough 98% of the time, and I rarely need to use the friction brakes.

      Another nice feature of the Tesla is that the regen is triggered merely by lifting off the accelerator, so you can practically drive with one foot. It's also arguably safer, because deceleration starts immediately with no lag from moving your foot to the brake pedal.

      --
      Weeks of coding saves hours of planning.
    2. Re:Braking by compro01 · · Score: 4, 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.

      --
      upon the advice of my lawyer, i have no sig at this time
    3. Re:Braking by dtmos · · Score: 2, Informative

      If I understand you correctly, the Prius has done this for a decade. One of my Priuses is at well over 100,000 miles, and still has its original brake pads. The only time the Prius' friction braking system is activated is during very slow speed stops (when there's not enough counter EMF from the generator to get significant regenerative braking), and during emergency stops (when maximum deceleration is requested by the driver). The rest of the time the car uses regenerative braking.

      What do you mean by sacrificing power? Regenerative braking returns some of the vehicle's kinetic energy to the battery, making the car more efficient.

    4. Re:Braking by Dun+Malg · · Score: 2, Interesting

      recovering a loss qualifies as a gain. It is, in fact, regaining.

      --
      If a job's not worth doing, it's not worth doing right.
    5. Re:Braking by shway · · 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.

    6. Re:Braking by PPH · · Score: 2, 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.

      --
      Have gnu, will travel.
  5. Anonymized Travel Data by Umuri · · Score: 2, Insightful

    Ok, so maybe someone can help me out here, but how exactly do you anonymize travel data?

    I mean sure, psuedo anonymized could be fairly easily done, just take the raw data, match with topographical data, and output the combined result devoid of geographic representations.
    But even that wouldn't be anonymized to anyone who's looking for info on a specific area, since the data would all be similar and it wouldn't be hard to detect a route that goes through a given set of terrain, especially if the start or stop points (someone's house/parking garage) is known.

    So someone who's more in-the-know with anonymizing data sets of this or similar nature able to shed some light on this?

    --
    You never realize how much manually made unmanaged "linked" lists suck, till you have src.link.link.link.link...
    1. Re:Anonymized Travel Data by Anonymous Coward · · Score: 2, Informative

      I think they answer this on their site: http://chargecar.org/privacy

      Two passages jump out:

      "To further ensure your privacy, the first and last tenth of a mile of every commute is automatically removed before it is saved to our servers, and no data from those omitted portions is retained."

      and

      "ChargeCar will also not disclose your position data to anyone and it will be used strictly for research purposes. Search capabilities are only as low as the city level. The only information that ChargeCar will share are velocities and altitudes over time, separated from the positional data you submit. "

      Now, it isn't clear that they won't keep the positional data after they extract the velocities/altitudes, but they say they won't share it.

    2. Re:Anonymized Travel Data by Blakey+Rat · · Score: 3, Insightful

      Ok, so maybe someone can help me out here, but how exactly do you anonymize travel data?

      You have a table of GPS tracks. And you have a table of cars. And the two tables have no columns in-common that could be used to join the data.

    3. Re:Anonymized Travel Data by vlm · · Score: 3, 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".

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    4. Re:Anonymized Travel Data by Michael+Woodhams · · Score: 2, Informative

      And here we see a completely anonymous GPS track starting at 47 Washington Ave, Charleston, California*, stopping for 30 minutes just outside "Bobbie's Big Bargain Bisexual Brothel" before continuing to parking space 15 at the Word Of God radio station. We have no idea what car it was.

      (P.S. others have pointed that this scenario will not happen, because they delete the first and last .1 mile of the trip.)
      * All parts of this address except 'California' were made up by me. Any resemblance to the address of an actual patron of Bobbie's Big Bargain Bisexual Brothel are purely coincidental.

      --
      Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
  6. Wow, look at that: by Culture20 · · Score: 3, Insightful

    "It seems that 99.9% of drivers drive the speed limit, and engine-break to lights."
    Do they really expect anyone who isn't already driving a hybrid or electric and/or driving super-energy conscious will be interested in helping a project like this and send in Data? How people really commute: They drive 10-20 miles over the speed limit on highways, and 5-15 miles over the speed limit on city streets. They speed up to get in front of a slower (but still over the speed limit) car, just in time to brake hard for the stoplight. The data they collect will say regenerative braking is pointless, but the common-knowledge data will say that regenerative braking is the bee's knees.

  7. Re:CMU can pay for it. by DemianJ · · Score: 2, Informative

    If I'm not mistaken, CMU has a small endowment for a University of its size and stature (Just over $1 Billion), you'll find it trailing many universities . That said, I believe CMU does receive more than its share of grant, research funds and donations (Tepper, Gates, etc...) for buildings, etc...

  8. Slightly related, open source electric cars by Aggrajag · · Score: 2, 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
    http://ecars-now.wikidot.com/

  9. Requires Cheap Batteries First by KalvinB · · Score: 4, Interesting

    According to http://www.sahkoautot.fi/eng:faq#toc3, 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.

  10. Re:CMU can pay for it. by tkrotchko · · Score: 3, Insightful

    Well, once would have to wonder if CMU produces any IP as a result of this free data, would they release all copyrights and patents for free?

    Or is that different?

    --
    You were mistaken. Which is odd, since memory shouldn't be a problem for you
  11. Re:The part of the story you're missing... by Jon+Abbott · · Score: 2, Informative

    I would suspect that this varies depending on the model. My Garmin 60csx has the ability to disable track logging. There have been numerous times where I've wanted it to record the track, but it had turned off track logging... Sounds like a good time to say "YMMV". :^)