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Power Transportation Hardware Technology

Driverless Cars Are Giving Engineers a Fuel Economy Headache ( 208

schwit1 shares a report from Bloomberg: Judging from General Motors' test cars and Elon Musk's predictions, the world is headed toward a future that's both driverless and all-electric. In reality, autonomy and battery power could end up being at odds. That's because self-driving technology is a huge power drain. Some of today's prototypes for fully autonomous systems consume two to four kilowatts of electricity -- the equivalent of having 50 to 100 laptops continuously running in the trunk, according to BorgWarner Inc. The supplier of vehicle propulsion systems expects the first autonomous cars -- likely robotaxis that are constantly on the road -- will be too energy-hungry to run on battery power alone. A fully autonomous subcompact car like a Honda Fit, for example, will get 54.6 miles to the gallon in 2025 in the best-case scenario, more than 5 miles below the U.S. emissions target, according to BorgWarner. A small pickup or SUV would be at 45.8 mpg, versus a target of 50. Engineers don't have much time to resolve this, as companies are planning to deploy their first fully self-driving cars in the next couple of years. One way for automakers to meet the power-hungry needs of self-driving systems will be to use gasoline-electric hybrid models rather than purely electric cars, said Mary Gustanski, chief technology officer of supplier Delphi Automotive Plc's powertrain business.
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Driverless Cars Are Giving Engineers a Fuel Economy Headache

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  • by bit trollent ( 824666 ) on Thursday October 12, 2017 @09:04PM (#55360021) Homepage

    Really? These engineers didn't consider that processing power is constantly shrinking and becoming more efficient?

    I feel like I'm reading an article from 30 years ago about how computers will never fit inside your home because the take up large rooms!

    • by ShanghaiBill ( 739463 ) on Thursday October 12, 2017 @09:25PM (#55360079)

      Really? These engineers didn't consider that processing power is constantly shrinking and becoming more efficient?

      Also, the claim that SDCs will have computers consuming 2-4 kw seems implausible. Tesla Autopilot consumes WAY less than that, and is doing basically the same thing in terms of processing sensory data. Waymo will have access to TPUs that can process vision data eight times more efficiently than GPUs, which themselves consume no where near 2kw. There may be some heavily instrumented prototypes that have 2-4kw of computing power, but that doesn't mean the production version will do that.

      • Perhaps the sensors' electricity consumption is included in the 2kw figure?
        • by rtb61 ( 674572 )

          The sensor suite for automated vehicles is key. What they can see, how far they can see it and how often they see it. How durable is it, how reliable is it. They really need to open up the sensor market and share methods until they get one that works reliably, whether passive or active. A encrypted lidar [] suite seems the only way to go, encrypted because each cars signal needs to be unique but it would also be useful to share and read signals from other vehicles (much like

          • The sensor suite for automated vehicles is key.

            Tesla uses 8 cameras, consuming less than 1 watt each.
            So where are the other 1992 watts going?

            • The sensor suite for automated vehicles is key.

              Tesla uses 8 cameras, consuming less than 1 watt each. So where are the other 1992 watts going?

              According to an article here earlier this week, LIDAR, more processing, and all the other systems that car companies say will be required for actual autonomous vehicles to function as opposed to what Musk and Tesla says will work. The Lidar also has to have sensor warts all over the car which also affects aerodynamics and fuel economy. They're building future cars with current equipment because you can't run vaporware through a government testing program. It probably all comes down to in theory, theory is t

            • Tesla also uses radar. That's an active sensor, so it's gotta consume a bit more than that.

              Other car companies use lidar as well.

          • You don't need to encrypt, just use random values. It's actually harder to predict if your rng works

      • by viperidaenz ( 2515578 ) on Thursday October 12, 2017 @09:45PM (#55360161)

        Tesla Autopilot is not much more than lane keeping and auto cruise control.
        It can't handle cross traffic without crashing into a truck. It's designed to only be used on motorways. It can't drive through a city. It can't read signs at an intersection to determine who gives way.

        Autopilot != self driving. It does exactly what an autopilot does, keeps you on course at the correct speed, and hands back control to the pilot when it detects a scenario that requires a decision.

        • Re: (Score:2, Insightful)

          Tesla Autopilot is not much more than lane keeping and auto cruise control.

          The sensors are the same. The low level image processing is the same. There would need to be some additional processing to handle intersections, etc. but it would be like maybe 10% more, not 2000%.

          The premise of TFA is nonsense.

        • So a car could run for most of the journey on autopilot, and hand over to the self driving system for short periods?
        • by Ost99 ( 101831 )

          You're describing the hardware in the first Autopilot (AP 1.0) based on Mobileye with one camera + radar. The current hardware has 8 cameras, radar and ultrasound sensors (AP 2.0).

          This video shows AP 2.0 hardware in action with an early version of the self driving software from last year : []
          Far from perfect, but it can do much more than just lane keeping and cruise control.

      • by AmiMoJo ( 196126 )

        Maybe they are using the radar to microwave the TV dinners that the car is front is taking home. Imagine how cool that would be, your car asks the one behind to prepare your evening meal ready for when you get home!

    • The nascent technology of diver-less, electric autos is such that gains in efficiency are inevitable.

      It also seems likely the technology will garner substantial government subsidies on the order of alternative energy generation, so the leaps in advancement will be measured in bounds.

    • It's not just the raw CPU processing power, it's also the sensors and specialized data reduction front-ends (FPGA) - sooner or later they'll get out of FPGAs, but with the rate at which these things are developing/changing, they'll probably stay re-configurable for awhile.

    • by Calydor ( 739835 )

      30 years ago?

      That was 1987. We had Amigas, I think the 386 architecture was in play at the time, the NES console was making its debut ... We already HAD computers in our homes by then.

    • My number one question is, what's the rush?

      It seems all the companies want to be the first to market a self-driving car, that's a given, but why rush into something that has to be done right or not at all? We don't need the first ones on the road causing all kinds of accidents and problems. Nothing will kill the interest in self-driving cars faster than an unreliable and dangerous vehicle that was rushed to market.
    • Really? These engineers didn't consider that processing power is constantly shrinking and becoming more efficient?

      I feel like I'm reading an article from 30 years ago about how computers will never fit inside your home...

      Perhaps you meant 50 years ago?

      (My Apple IIc is 33 years old, and can fit in a backpack.)

    • I feel like I'm reading a response from 50 years ago, when we were all going to have flying cars and live in glass boxes and only have to work 20-hour weeks because computers would do everything for us.

      Moore's law is dead [], I wouldn't count on it for future planning. Any space savings is going to come from custom ASICs, which means you're going to be even more at the mercy of the manufacturer for spare parts (and you'll never be able to ride in a "classic" self-driving car, as they'll all be dead from bit ro

  • by freeze128 ( 544774 ) on Thursday October 12, 2017 @09:12PM (#55360041)
    The answer is simple: Outsource the processing power to an overseas call center where your virtual driver (Let's call him 'Steve') will steer the car in a simulator-like environment. A few webcams around the car will certainly use less power than that huge LIDAR pod on top of WAYMO cars.
  • I run a small cluster on less than 2kW of power which would include 3 nodes with each 16 cores, 256GB RAM, 1TB in SSDs and a Tesla GPU.

    Just to give you an idea, 2kW of power on your standard 12V car requires a current of 167A.

    I'm not even sure what you would have to put in to get a package of 2kW, that's 2000W. Camera's take up less than 2W each, even if you need 10 of them, you're still at only 20W LIDAR take up perhaps 10W each, one for each end of the car is another 20W. Give or take another 10W for vari

    • by Anonymous Coward

      How much power does the omni directional LIDAR array of your cluster use? Oh, it doesn't have one that works at highway speed and distance, much less allow for cross traffic?

      Well then, my welcome mat at home uses zero power and is about as relevant as your anectdote. Thanks for telling us all about your cluster. Do you not have a TV? Oh wait you must, because you would have told us if you didn't. You are that guy.

      • by guruevi ( 827432 )

        I looked one up for you, the price tag isn't great at $10k but it only consumes 7W and can "see" 100m.

    • Just to give you an idea, 2kW of power on your standard 12V car requires a current of 167A.

      I think I just found where a lot of the power is consumed. 167 amps is a lot of current, that means I^2*R losses.

      The total power of the individual pieces and parts might be far less than 2kW, but add in losses to heat in the wires because everything is running on 12-14 volts and that might just add up to quite a bit of power loss.

      Then again I might be completely wrong.

      • It's almost like that can be fixed with a small amount of cabling. Speaking of I^R losses a car is not big enough to worry about the power loss. If that power is significant enough then you're sitting on one giant fire hazard smelling of outgassing insulation.

        Oh and since EV batteries are typically quite high voltages is unlikely to be an issue that isn't resolved with a small power supply.

    • by pnutjam ( 523990 )
      Well, each of the nodes will be running a full windows stack and some sort of wireless channel for side loading ads, those have to be flashy too.
  • by SumDog ( 466607 ) on Thursday October 12, 2017 @09:21PM (#55360069) Homepage Journal

    Self driving cars in Europe might be neat where they don't have transportation shortages. In America, our mass-transportation infrastructure is non-existent. Except for a handful of cities, you have to own a car in order to simply function in society, or you have to find a job that lets you work from home or live in a very limited area of town.

    I wrote a post about this a while back:

    Basically even if you had Interstates which only allowed self-driving cars and all of them could travel at over 120kph bumper-to-bumper and all of them were filled with four people each, you still wouldn't even get to 10% of the capacity of a traditional rail system, running on a single track, with trains arriving at 5 minute intervals (and most cities with rail systems have them arriving at 2 min intervals during rush hour. London has several automated trains. Singapore is fully automated).

    Before we start dumping billions into subsidizing self driving cars, how about we build up our self-driving train tech; a known technology which currently exists and transports millions of people every day.

    • How do you get from the terminal to your work, though? In Europe and New York, you can walk. Or, because they're high density, hop onto a subway. We're much too spread out for that to work. Sure, you can argue that we should be more dense, but face it: that's just not going to happen anytime soon.

      • by SumDog ( 466607 )

        America didn't get as spread out as it is overnight. You start laying down rail, you will see businesses start to pop up around each station. We can get back to a sustainable city-scape again. America use to be walkable. It can be again.

        • Yeah, it didn't happen overnight. And it won't change overnight, i.e., "anytime soon."

          When was America walkable? Maybe for a very short time between the rural to city migration, but a short period of history isn't gospel. It wasn't really all that long after America became "urban" that cars started forming "suburban."

          We have modern attitudes about urban/suburban/rural, but that's not snobbery or even necessarily automobile related. We developed a hell of a lot differently than most of the world. Compare us

        • America pretty much started spread out. Small villages surrounded by farms. Surrounded by forests. Surrounded by water.

      • Rail works great it does not work better than cars till it reduced your real commute time. The rest of the world has high-speed trains the US thinks acella is fast and that making a 100-mile detour to Providence makes sense (does politically 2 senators). We need real high speed rail in new corridors with enough parking rather than trying to improve existing over-congested lanes.

        The build it denser sucks, high density living is horrid. I'm 60 ish miles outside NYC get that door to city center commute time

    • That's absurd. Trains full works great for a city like London or cities in the US already serviced by trains. It makes no sense at all even for the Bay Area, and then when you get to flyover states - WTF, who would full trains coming by every two minutes make sense for the typical US small city with extended suburbs?

    • Because American urban and suburban populations are too spread out for efficient use of mass transportation. I live about 45 minutes from the closest station for my city's rail system, and then probably another 45 minutes ride on the train to the stop closest to my work plus another 15 to 20 minutes to wait for the bus that runs from the stop to my work. Or, i can drive myself and be there in 45-60 minutes. There are many more people like me that would benefit from autonomous cars then there are people w
    • You present an incredibly well reasoned argument, and if humans were logical on the order of the Vulcans, there would be no viable position against it.

      Yet, there are people aplenty who will not ride the train, in the same fashion that they won't wait for appointment TV. It's either slightly inconvenient for them, or significantly beneath their imagined station in life.

      • by Pulzar ( 81031 )

        Yet, there are people aplenty who will not ride the train, in the same fashion that they won't wait for appointment TV. It's either slightly inconvenient for them, or significantly beneath their imagined station in life.

        There are plenty of very rich folk living in Manhattan that take the train every day.

        Many people I know would take the train, if there was one. I don't think the "status" thing is holding people back. Having the nearest station as close as the final destination, trains averaging a quarter of

        • Manhattan, [] though, seems like a poor representation to multiply exponentially from, in the attempt to predict nationwide usage.
        • I know a bunch of people that won't take trains with good reason, the stations are not safe crime wise, center city of feeder cities are pretty rough generally.

    • Why would we need driverless trains? Driverless buses, on the other hand would be very appropriate. It would be especially nice if there was some sort of scheduling and routing flexibility to reduce dependence on static routes and times. In fact, we could start building scheduling and routing apps right now, then they can meet in a convergence with the driverless tech some years down the road.
    • You're completely missing the point of self driving cars. It's not the LONG trips on a highway that this will be hugely impactful for, it's the shorter ones in town. People don't take transit in a lot of cases because they aren't near transit. A SDC can get them that last mile on both sides. Your car takes you to the subway and then drops you off and heads back home to park, for example. Or even better, *you don't even own a car any longer* and just belong to a car share cooperative that can summon an SDC t

  • 1) Despite the general belief, driverless has NOTHING to do with all electric. Yes, there will be a competition.

    2) Eventually, the computing power and sensor tech will improve power efficiency, allowing both in the same car. Expect that to happen 5-10 years after the first one becomes ubiquitous.

    3) I bet they are underestimating how much power they will save by getting humans out of the loop.

    4) You can probably decided to turn the AI off to drive long distances, thereby saving battery life.

    • 4) You can probably decided to turn the AI off to drive long distances, thereby saving battery life.

      I'd say that is the most unexplored way of saving energy. A properly designed system will demand substantially less power in some situations, and much more in others. Probably, today's prototypes draw the same kind of power when the car is stopped waiting for a traffic light, when the car is cruising alone, when you approach a busy intersection...

      "Premature optimization..." and all that. You first get a system that works, then you tweak it. We are still getting the working system, optimization will have to

  • by fahrbot-bot ( 874524 ) on Thursday October 12, 2017 @09:33PM (#55360119)

    ... the equivalent of having 50 to 100 laptops continuously running in the trunk, according to BorgWarner Inc.

    Apparently, Resistance isn't futile it's V / I.

  • by ebrandsberg ( 75344 ) on Thursday October 12, 2017 @09:36PM (#55360125)

    Consider: Many long-haul trucks operate mostly on well maintained highways between distribution centers. Ten or more of them could be linked together scanning for issues, and communicating with each other, possibly with a lead car in the front that can react to accidents and incidents before they even pass, similar to over-sized loads on the road today. Even if not driving between distro centers, they can use existing rest-areas as stopping points where local drivers can take over in shifts.

  • So they're saying we should be wary of the consumptive nature of the hive mind in the trunk?

    I should have expected no less from Borg Warner.

  • Two to four kilowatts in an electric automotive application? So what's the problem? Accelerating a ton of metal takes a HYSTERICAL amount of electric power.

    A horsepower is almost exactly 3/4 of a kilowatt. So four kilowatts is 5 1/3 horsepower.

    A vehicle just cruising at highway speeds takes teens of HP just to fight wind resistance and rolling friction. (Numbers from a long while back, so aerodynamic improvements may have brought it down a bit, though I doubt it's under ten HP.) Accelerating takes a lo

    • by b0bby ( 201198 )

      My electric car averages about 4 miles per kWh in mixed driving, so 2-4kW would really put a ding in my range. I doubt it will come to that, though.

      • by Ost99 ( 101831 )

        That means your range would be reduced by 8-16 miles per hour of driving.
        The most power hungry level 5 computer meant for production vehicles is the Nvidia Drive PX Pegasus at 500W. That would eat up 2 miles per hour of driving.

  • Nonsense (Score:5, Interesting)

    by crow ( 16139 ) on Thursday October 12, 2017 @10:13PM (#55360251) Homepage Journal

    This is calculations based on wild assumptions about what is actually required for self-driving. If Tesla is right, then they can do it with the hardware that is already shipping, so power is not an issue--they just need to finish the software. You can also look at what Nvidia just released that they're billing as being designed for self-driving cars. AMD is apparently working on a similar product.

    This sounds like a typical naysayer making stuff up to get attention (and advertising hits).

    • The truth is generally somewhere in the middle.

      I imagine ultimately the sensor array, whatever it may be, will consume around 2-500W; the processing will likely end up with redundant systems, coming in around 2-300W. You will have communication to share information between cars in order to improve distance data, and that may add another 20-50W. Generally manageable, although city driving might take some real time to mature to the point that it fits within this energy profile.

      • by crow ( 16139 )

        If you assume 300Wh is a mile of range, then you're talking about consuming one or two miles of range per hour of driving. That's not bad.

  • What kind of a person gets excited about a driverless car? What's the fun in that? I just don't get it.
    • by kamapuaa ( 555446 ) on Thursday October 12, 2017 @11:56PM (#55360483) Homepage

      The sort of person who lives at point A, and works at point B, and has to get up in the morning to drive the same route from A to B and then later in the day drives from B to A every day. Driving is an hour and a half a day (mostly) wasted. If I could sleep or work or jerk it for an extra hour and a half every single workday, I feel like my quality of life would be improved. Just that alone would be an extra 400 hours/year.

      • You have my sympathy for your drab existence.
        • Re: (Score:3, Funny)

          by dunkelfalke ( 91624 )

          It seems to me that since apparently driving a car is your only joy in life, you should be the one who is pitied. Why won't you become a taxi driver?

          • Let me guess, couldn't pass the driver's test now you have a grudge against motor vehicles?
            • Let me guess, couldn't pass the driver's test now you have a grudge against motor vehicles?

              Driving a car is one of the most dangerous things humans do on a daily basis. 40,000 people die every year doing it, so don't be ignorant as to the parents point. The old-fashioned mentality of being forced to drive to a building every day and sit in front of a computer to do a job that could easily be done from home needs to die.

              My commute time was at least 2 hours every day. That's 40 hours a month wasted sitting in a car. I told my employer I would give them half of that wasted workweek back in exch

              • I don't understand why anyone would get a job 1+ hours away from home and then complain about it. Kind of like getting a house next to a train track and complaining about the noise. You probably have that commute because you make more money in that scenario. So fine, that's the trade-off you made, now live with it.
              • Do they fail to understand or do they not care? It's not their problem if you spend 2 hours a day driving.

        • Similarly, if the highlight of your life is your drive to work, you must have just about the most life imaginable - which would explain why you take out your bitterness by being an asshole on a technology website.

      • If I could sleep or work or jerk it for an extra hour and a half every single workday, I feel like my quality of life would be improved

        I think if you jerked it for a *extra* hour and a half every day, your dick would fall off and your quality of life would be greatly reduced.

    • People who commute. Those who consider driving as "fun" are those who typically shouldn't be doing it on the road, or at least on a busy road.

      I would pay top dollar to recover 8 hours of my week, 48 weeks of the year which are otherwise completely fringing wasted doing the single most mind numbing thing people routinely do.

      Who would want a self driving car? Those who fall asleep at the wheel. Those who'd rather watch TV. Those people who get dressed in their car, put on makeup in their car. That stupidly la

      • Well none of you can be working too hard, you all seem to have plenty of time to waste on this site.
  • by RhettLivingston ( 544140 ) on Thursday October 12, 2017 @10:50PM (#55360351) Journal

    The NVidia or other GPU approach to AI is too flexible for this application. It needs a more purpose-built chip. Perhaps something like IBM's TrueNorth or even a mixed analog/digital NN approach.

    NNs in general have potential to be much more power efficient than traditional computing with vectors makes it appear, but not when we use traditional computing techniques to simulate the NN.

    We will see this evolve quickly as the market appears. It's still quick and dirty time right now.

  • by locater16 ( 2326718 ) on Thursday October 12, 2017 @11:06PM (#55360387)
    A Tesla Model S has a 90 kilowatt hour battery life for it's 275 mile range. A kilowatt hour is a thousand watts, and let's assume you're going 60mph. For argument, and maths, sake we'll assume you're going above efficiency and say you'll get 240 miles out of that. That's 4 hours, so 22.5 kilowatts an hour. That's a powerdraw of 22 thousand watts in 1 hour. The new self driving chip announced by Nvidia only draws 500 watts, that's 500 watts in an hour. Or better yet, here's the empirical evidence of Tesla owners discussing their average watts/min usage: []

    Even there with more efficiency, the new Nvidia chip uses in an hour less energy than the car itself uses in 2 minutes. This article is absolute bullshit, they had 1 damned thing their job required and they didn't do it. Self driving electric cars are perfectly mathematically sounds.
  • Instead of worrying about the efficiency of something that might be made in 2025, let's worry about how much power these things consume when someone actually builds a fully functional one that is for sale.

    Then we will at least have a metric for comparison and competition.

  • This sounds stupid, and also, even if it were true then this is something that gets solved the more autonomous cars you get on the road:

    * You get more computer driven cars on the road, the roads will become more computer-car friendly. Think of signs or markings on the road that will tell the car where it is, or what kind of hazards are coming up via for example a QR code.
    * Once you get more driver-less cars you get inter-car communication. Car up ahead does the full sensor sweeps and pass the results down t

  • obviously they are running alpha versions of the hard and software, yes, it will be 30 laptops in the boot. the production model will be nothing like this.
    just look at alpha versions of computers from the old days, it filled several tables of boards and wires everywhere, still in the end you get a nice small box.

  • I thought there were efficiencies to be had from a self-driving car being able to optimize acceleration, braking, and with car-car communication, greatly reducing a lot of the stop/go in congestion. It should be able to reduce the power consumption of the engine/motors over the way humans accelerate, brake, and speed up and slow down too often.

    These won't make up all the losses to self drive, but won't they offset some meaningful percentage? 5% or so power consumption from the drive system through efficien

  • It seems a bit disingenuous to suggest that *experimental* systems that are running on general purpose computing platforms are going to be the actual endgame and then using that to decide that self driving cars are going to have a problem with power consumption. Of course, I don't know what the specific tech involved in each self drive system actually is. However, because everything is experimental at this point, it is pretty much certain that nothing is optimized. It would be a waste of resources to optimi

Can anyone remember when the times were not hard, and money not scarce?