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Transportation

Camless Internal Combustion and the Digital Age (hackaday.com) 383

szczys writes: The internal combustion engine is amazing, and it continues to evolve. Carburetors gave way to fuel injection, and a computer now monitors all kinds of sensors to ensure these engines operate at peak efficiency. But there is one thing that has remained largely unchanged: the cam shaft. This is a device responsible for mechanically timing the operation of the cylinders. It's possible to build an engine that uses digitally controlled actuators instead of a camshaft to decide when each cylinder should fire. These exist as prototypes — we have the technology, so why aren't we building with it? The answer is that change is hard, and as with the carburetor it could take an outside force (in that case mandatory efficiency benchmarks) to get automobile manufacturers to wager a bet on new technology.
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Camless Internal Combustion and the Digital Age

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  • by chromaexcursion ( 2047080 ) on Tuesday February 16, 2016 @06:44PM (#51523227)
    The fundamental parts of the engine are all mechanical. They work without a battery.
    Resilience to electrical failure is important.
    • by jonnythan ( 79727 ) on Tuesday February 16, 2016 @06:53PM (#51523315) Homepage

      Like fuel injectors and fuel pumps?

      No modern car engine will run without electricity.

      • by Brandano ( 1192819 ) on Tuesday February 16, 2016 @06:59PM (#51523375)
        But the failure of a mistimed valve is way more catastrophic than that of a misfiring injector or spark plug. Even if an electrically actuated valve system was to be used in production I'd expect it either to be supported by a backup mechanical system or to be designed never to interfere with the volume occupied by a piston. In the first case the electronic valve would be an additional cost only justified on high performance engines, in the second case it would affect the performance negatively. Perhaps this could work with sleeve valve engines?
        • by jo7hs2 ( 884069 ) on Tuesday February 16, 2016 @07:02PM (#51523397) Homepage
          Yeah, the idea of something smashing into something else due to a failure is what concerns me. I've already experienced what happens when a camshaft position sensor fails gradually enough that it doesn't trigger a fault in a computer...nasty ignition timing with backfires at high RPM...a Ford Taurus belching fire on the highway...and the idea of parts flying around without protection is why I don't own an interference engine. https://en.wikipedia.org/wiki/... [wikipedia.org]
        • by sjames ( 1099 )

          Probably we'll end up with valves that fail closed so they won't strike the piston.

          • It would depend on the type of fail. If something happens to alter the timing it might not even register a fault condition until after the fact. What could cause that would need to be investigated and protected against.

            • by sjames ( 1099 )

              Yes, there could still be failures of other parts that would cause a piston strike. But those exist with cam driven valves as well.

          • I assume the electric valve system would use something like a solenoid to push against the valve stem supported by a spring. The solenoid would need a force exceeding the force of the spring to open the valve.

            I'm not an expert here, so please correct me if I'm wrong. One thing about solenoids is that they are either on or off or at least the times to actually activate the push on the valve to full open or release its force for full close are pretty short. Cam shafts are shaped for a more controlled valv
            • EDIT: I guess the valve stem could be the shaft inside the coils of the solenoid. Another point is valve springs have incredibly high force constants - they are really hard to push. This might take a pretty high current to open the valve.
            • by sjames ( 1099 ) on Tuesday February 16, 2016 @08:45PM (#51523989) Homepage Journal

              In general, solenoids are either on or off, but that is not intrinsic to their design. Opening and closing times can be altered either electrically or physically (for example, using soft iron to slow the magnetic field's change).

              On some large diesel engines, the valves are driven hydraulically or pneumatically with solenoids just activating small control valves. On those, it's fairly easy to shape and position cylinder outlets to give it a (relatively) soft close.

              The rest, as you pointed out is a cost/benefit analysis.

              I can see some potential in the technology, but you won't see me buying a production car with it for the first few years after introduction.

            • by caseih ( 160668 )

              Solenoids can be driven with PWM. This is commonly used in hydraulics. Granted response time is slower on a hydraulic spool but I'm sure pwm would still work for this application.

            • I'm not an expert here, so please correct me if I'm wrong. One thing about solenoids is that they are either on or off or at least the times to actually activate the push on the valve to full open or release its force for full close are pretty short.

              The WVU version of camless engine uses rwo solenoids per valve. one to open, and one to close.

              Cam shafts are shaped for a more controlled valve action. I would guess that one could control the current through the solenoid coils to match that of the cam action. All this would mean computer activity, control circuits and a substantial increase in electric energy use.

              Pulse shape probably. Pulse shape is already used to control fuel injectors - and oddly enough one of those adjustments is sometimes made for RFI abatement.. A square wave pulse on a fuel injector generates a lot of Radio frequency interference But you can make an a valve actuator timing adjustment the same way.

              Also, there needs to be a serious comparison for failure modes between the two systems for reliability purposes. There are some common failure points such as a broken valve spring,

              Non interference engines would be a must.

              What is needed to judge how much this would help or not is if

              • Non-interference has all but disappeared, because of higher efficiency of interference engines.

                However, people seem to be misunderstanding the function of the electro-pneumatic valve. The electric solenoid would only OPEN the valve, with a pneumatic system returning it to close position. Electronic failure? Valve closed.

        • This. Valves getting stuck closed? Non-catastrophic failure, the engine runs like crap until you get the problem fixed. Valves stuck open? Piston slams into them, bending or breaking the valve, ruining the valve guide, and very likely breaking the piston. Might even damage the connecting rod and it's bearings. Not a trivial repair, at that point you have to tear the entire engine down and inspect all of it, probably cheaper at that point to just rebuild it completely or replace it. Meanwhile camshafts last
          • Most gasoline engines -- at least in the US -- are non-interference designs -- the valves never extend into space potentially occupied by a piston. Presumably because the designers don't want failure of a $100 timing belt to destroy the engine.

            • by guruevi ( 827432 )

              That really depends. Most 'japanese' brands (Hyundai, Nissan, Mitsubishi) have interference designs. For Ford and GM vehicles it really depends on the engine, they have some interference, some non-interference.

            • by dgatwood ( 11270 ) on Tuesday February 16, 2016 @09:20PM (#51524201) Homepage Journal

              I didn't think anyone still built interference engines, either, but apparently at least as of two years ago, a lot of smaller engines used interference designs. With that said, AFAIK, there's no technical reason that government safety standards couldn't mandate that electronic valve timing be used exclusively with non-interference designs. That would probably go a long way towards ridding the world of interference engines, at least in the long run, which would be IMO a good thing.

              For that matter, the main reason that valves are designed the way they are designed is that they have to be operated mechanically using simple levers. With an electronically controlled valve, at least in principle, there's no reason the valve couldn't be built in such a way that it either:

              • Opens outwards
              • Opens by sliding
              • Opens by iris action

              Any of those would eliminate the risk of the head colliding with the valves, and that last one could potentially also allow the ECU to individually adjust how much the valves open based on temperature, throttle, etc. much more precisely than any purely mechanical design, which might be beneficial in terms of fuel efficiency, noise, etc., or at least might allow them to eliminate external hardware that regulates airflow, thus reducing the overall cost of the engine.

              That said, I am not an engine designer, so this is mostly speculation.

              • I didn't think anyone still built interference engines, either, but apparently at least as of two years ago, a lot of smaller engines used interference designs.

                Yeah, you have it backwards. Non-interference designs are the ones that have all but gone away. Subaru, Nissan, they've all gone interference.

                For that matter, the main reason that valves are designed the way they are designed is that they have to be operated mechanically using simple levers. With an electronically controlled valve, at least in principle, there's no reason the valve couldn't be built in such a way that it either:

                Opens outwards
                Opens by sliding
                Opens by iris action

                No, that's not true. There are good reasons why a valve has to open and close the way it does, although yes, it could open outwards. An iris would be too fragile. A sliding valve would wear its seals. Nobody is making an iris, but you can get the equivalent of a sliding valve from Coates right now. You can get a small block chevy up over 10,000 RPM by replacing the va

        • And it's also entirely possible to engineer it correctly.
          A bridge that fails is also pretty catastrophic, but oddly enough engineers have also dealt with that problem and no one is scared of bridges.

          We are at the stage of having computers self drive cars, but the moment a computer looks like it could control a engine valve suddenly it's a ridiculous idea?

      • by jo7hs2 ( 884069 )
        But they WILL run without the battery.
        • by jo7hs2 ( 884069 )
          Just not without electricity.
        • by Pascoea ( 968200 )
          Yeah, they will run without the battery. Previous post said "No modern car engine will run without electricity" Without battery != without electricity. A modern car will not run without electricity.
        • by sjames ( 1099 )

          But they won't start without one.

          • unless you know how to push start a car with a manual transmission. You know "stickshift" ;)

            • by sjames ( 1099 )

              Sorry, no. If you remove the battery or run it completely flat, the fuel pump won't run, injectors and the spark plugs won't fire.

              You're thinking of the far more common case where the battery is present but too weak to turn the starter. In that case it still has enough for the plugs, injectors, and fuel pump so a pop start (push start) can work.

              Most motorcycle engines actually don't need a battery since they use a magneto connected to the crank shaft to fire the plugs.

      • Yes, someone is hugely behind the times it seems.

        BTW, so is the writer of the article, Lamborghini and a few others have production engines with electronically actuated valves
        (not electro-mechanical valve phased cams like many many engines have had for a while).
        This is old old tech in such areas of F1, etc.

        The largest issue is cost versus advantage, there is a lot of the first, and not much of the second.

    • The fundamental parts of the engine are all mechanical. They work without a battery.

      Resilience to electrical failure is important.

      The fundamental parts of the engine are all mechanical. They work without a battery.

      Resilience to electrical failure is important.

      Critical components of your engine, i.e. fuel injectors, ignition, your high pressure fuel pump all work with electricity from the 12V system. On most newer cars, so does the throttle body (it's no longer actuated by a cable from the accelerator).

      Resilience to failure in an interference engine can be achieved by failing closed, i.e. if the valve actuators lose power, they should close to move out of the way of rising pistons.

      The bigger reluctance on the part of auto manufacturers is probably reliability giv

    • by tlhIngan ( 30335 ) <.slashdot. .at. .worf.net.> on Tuesday February 16, 2016 @07:31PM (#51523593)

      The fundamental parts of the engine are all mechanical. They work without a battery.
        Resilience to electrical failure is important.

      The sparkplug of a gas engine requires... electricity.

      A modern car engine uses an ECU which regulates spark timing and the transmission (usually called a PCU or Powertrain Control Unit nowadays) - it adjusts the spark timing and spark power based on the load of the engine. Lose battery power and the ECU goes dead. Depending on the vehicle, if you drop the battery, it may or may not continue running - the alternator will produce more than sufficient power to keep the engine running, but the battery provides voltage regulation of the entire system.

      And there are still completely mechanically driven engines - small aircraft use them, and they're a PITA to manage because you have to manually adjust the mixture (fuel-air ratio) for optimum power as you change altitudes. Experimental avgas aircraft, and production diesels (running on Jet-A) use a FADEC (Full Authority Digital Engine Control) which runs off the ship battery and a backup battery that fully controls the engine. The pilot only has a lever that tells the FADECs (there are two of them for redundancy) how much power to develop - the FADEC figures out the optimum settings to achieve that. You get an increase in efficiency, a decrease in pilot workload and all around increases in efficiency.

      Heck, Electronic Fuel Injection isn't on aircraft engines yet - yes, they've had fuel injection for around 25 years or so but it's generally of the continuous spray type.

      As for this, it does have some advantages like extreme variable valve timing. Hybrid cars, for example, often use a modified Atkinson cycle engine (modified because it's really an Otto cycle engine, with the intake valve kept open well into the compression stroke to reduce the fuel charge). Atkinson engines are extremely efficient - they have a small intake and compression stroke but a large power stroke (the goal is at the end of the power stroke to have 0 differential between cylinder pressure and air pressure, thus ensuring you have extracted all the energy).. But at the same time, Atkinson engines don't develop as much power. Being able to switch operating modes on the fly can be useful in pure gas-only cars - switch to Atkinson during low power for maximum efficiency (idling, highway), while being able to switch to Otto when you need power (accelerating, for example)

    • by msauve ( 701917 )

      there is one thing that has remained largely unchanged: the cam shaft

      The author apparently hasn't heard of two stroke or Wankel engines.

    • Wankel engines don't have valves, so no cam shaft.

      Also, small two-stroke model airplane engines (the type with glow plugs that run on nitromethane fuel) don't have valves, so again, no camshaft.

  • by Anonymous Coward

    Camshaft hooked up to my Raspberry Pi. Ruby on Rails controlled Iot webserver platform with home automation built in. Insteon X10 platform protocols provide robust social media sharing.

  • by Thelasko ( 1196535 ) on Tuesday February 16, 2016 @06:44PM (#51523241) Journal
    rumor is the hydraulics used a ton of power. The thing was much less efficient than a traditional cam driven engine. Sure, the valve timing and lift was perfect, but it was otherwise a nightmare.

    Ever break a timing belt on an interference engine? Very bad.
    • by lgw ( 121541 )

      Well, TFS says

      digitally controlled actuators instead of a camshaft to decide when each cylinder should fire

      Which isn't what a camshaft does. Ignition timing has been "digital" in most cars for some time now.

      rumor is the hydraulics used a ton of power. The thing was much less efficient than a traditional cam driven engine. Sure, the valve timing and lift was perfect, but it was otherwise a nightmare.

      My car has camshafts, but the timing of the open and close is plenty computer controlled. You don't need actuators to open and close the valves, you only need hydraulics to make the cams "bigger" when more power is wanted, or alternately to start opening a (usually much larger) set of valves past a certain RPM (insert "VTEC kicked in!" meme jpg here).

      It's not like you need to calculate cam pro

      • Well. ... It would be good to calculate cam profiles on the fly. Changes in duration and lift as well as timing the actuation can give better performance and power at different rpms and fuel pedal position. This can even be desirable as boost pressure changes with turbo engines. Although I'm not to up on that last one but I think it is the principle behind variable valve timing.

        • by lgw ( 121541 )

          Yep - that "envelope" of timing vs rpm ve power demand can all be pre-calculated and built into VVT systems. Some are simply RPM based, some are more fancy.

    • by SumDog ( 466607 )

      Wait, I thought this was already implemented in Formula 1 cars? They don't have cams at all. They use pneumatic air injection and get up to 22,000 rpm....or at least they did before they switched to smaller engines and turbo chargers.

  • by Anonymous Coward on Tuesday February 16, 2016 @06:46PM (#51523253)

    It's possible to build an engine that uses digitally controlled actuators instead of a camshaft to decide when each cylinder should fire.

    Camshafts don't control when cylinders should fire, that's an already replaced component called the distributor. Camshafts control the timing of inlet and outlet valves, and there are already formula one and other engines using electronically actuated pneumatic valve lifters.

    The problem is that cam shafts are very reliable, and a single fault in valve timing, in an interference engine especially, results in catastrophic engine damage, so the software and hardware has a very high bar to meet for it to replace mechanical cams.

    Also firstpost.

    -puddingpimp

    • Camshafts don't control when cylinders should fire, that's an already replaced component called the distributor.

      There is a technology called Homogeneous Charge Compression Ignition [wikipedia.org] (HCCI for short), that has the capability of running a gasoline engine without a spark. It's like The Holy Grail of combustion. That technology requires variable valve lift, timing, and duration. Cam-less technology would be an enabler.

    • by swalve ( 1980968 )
      What's the distributor driven by?
  • I'm far and away not an engine guy, but I always thought the reason was limited lifespan of solenoids.

    A cam is just a spinning part. A solenoid would have to electrically activate perfectly every time, thousands of times a minutes, for 15-odd years of usage. To match that kind of usage, you're talking some serious solenoid. Probably they do exist but they're not exactly standard hardware, as far as I know.

    And even the article suggests you tinker with models where the pistons can't crash into the valves.

  • by leftover ( 210560 ) on Tuesday February 16, 2016 @06:55PM (#51523347) Homepage

    One of the big limiting issues in this field (BTDT) is energy consumption by the actuators and associated circuit components. Valve are heavy relative to the accelerations needed by the motion profiles. This results in ferocious energy use and dissipation.

    If this power consumption is more than the engine power/efficiency gains from tinkering with profiles, the answer is an easy No.

    My only relevant direct experience was for an R&D engine to test different cam profiles without having to grind sets of camshafts. It used plant electrical power, can't remember exactly how much but the equivalent horsepower was in the teens.

    • Re: (Score:3, Informative)

      by pz ( 113803 )

      In doing a quick search for a mis-remembered car that I thought had an all-electric valve train, I came across some fellow's back-of-the-envelop calculations suggesting it would take about 20 KW to run a car's valvetrain electrically. That's a heapload of power.

      Naturally, much of that power is likely dynamic (accelerate the valve mass, so put energy into it, then halt the valve mass, pulling energy back out, repeat indefinitely). Doing it efficiently is going to be a bear with wires of normal conductivity

    • I'm talking out of my butt here, but why not drive the valve operation with hydraulic power generated via a mechanical pump connected directly to the engine drive, then the electricity needed to to direct that hydraulic pressure where it is needed becomes pretty trivial, right? Now the same mechanical energy that was operating the cam is left in it's mechanical state; and you don't have the efficiency loss of converting the mechanical energy into electrical energy needed to drive big beefy solenoids.
      • System I worked on did use hydraulics, electrical actuator operated a pilot valve. Hydraulic pumps don't turn for free either.

    • This. It is not uncommon for valve springs to put just shy of 100 lbs of force on the seat, holding the spring closed; and, 300-400 lbs of force on the spring when the valve is open in order to guarantee that the valve closure acceleration is high enough during high RPM operation. These are the kinds of forces you have to replicate with your hypothetical actuator. It can be done; but, it is so energy intensive that the current generation of engines using roller cams and VVT are the more efficient solutio
  • by mykepredko ( 40154 ) on Tuesday February 16, 2016 @07:02PM (#51523395) Homepage

    Seriously. If the technology is mature (regularly survives a 500 mile race) while providing tangible benefits (more horsepower meaning a faster car with better fuel economy which means fewer pit stops) customers will demand it.

    Otherwise, it's of no perceived value to customers and might be seen as just another piece of electronic junk that is being foisted upon them (like anti-lock brakes for those of us who remember people who couldn't see their value).

    • I can bet you that NASCAR, which only recently went to electronic fuel injection and ignition systems, is not going to allow variable valve timing any time soon. They have enough trouble keeping the teams from bending the rules now, I'd hate to see how hard it would be to regulate this thing. Also, going 500 miles at 200mph is one thing, going 200,000 miles at 70mph quite another. Where they are related in some ways, they are different problems.

  • Automakers embrace whatever gets people to chose their car over the competitors car, is cost effective to manufacture, and is reliable enough to get past the warranty period but not so reliable the car last too long past the warranty.

    There were fuel injected cars long before it was practically mandatory. I believe there were Corvette's from the 1950's that had early fuel injection. I test drove a 1982 Fiat that had it. Fuel injection was slow to be adopted due to cost benefit ratios along with performanc

    • The old 50's Corvettes used purely mechanical fuel injection that not only was complex and hard to maintain, it required frequent maintenance. It was phased out after 1965. It bears literally zero resemblance to modern fuel injection systems. The first mass produced digitally controlled fuel injection made by GM showed up in the 1982 Corvette. It was a throttle body injection system that, in various forms, lasted through the 80's into the early 90's. But by 1984, GM started with port fuel injection tha

    • by dwywit ( 1109409 )

      Hope this doesn't count as a Godwin, but the germans were using fuel injection in their WWII fighters, and it proved a significant advantage over carburetted allied fighters - the FW-190 could perform a radical nose-dive which would leave a Spitfire fuel-starved.

      Fuel injection has been around a LONG time - just like disc brakes - but they both took a long time to make it to mass-production motor cars.

  • What it really means is that the efficiency improvements are so poor it is not worth the additional cost. Unless some government agency, for good reasons or for bad, forces the manufacturers to change it is not worth it.
  • by labnet ( 457441 ) on Tuesday February 16, 2016 @07:10PM (#51523469)

    Here is an example of a cam-less engine that has been in development for over 10 years.
    http://www.dukeengines.com/ [dukeengines.com]

  • Just a reminder, when your fuel injector goes tits up, you just replace the fuel injector. When your timing belt/chain breaks ("digital" or mechanical), you replace your engine.
    • Just a reminder, when your fuel injector goes tits up, you just replace the fuel injector. When your timing belt/chain breaks ("digital" or mechanical), you replace your engine.

      Not all engines will suffer internal damage when the valve timing gets out of hand. Many will, but some survive it just fine. It depends on the design. Sometimes there is clearance between the piston top and the open valves. Now, if you are not driving one of those designs, then you'd better be designing your "digital" system to fail safe, I.E. Fail in such a way that the valves don't open at all.... Having a valve and piston come into contact can be catastrophic for a lot of expensive to replace parts

  • I have a 1991 Mazda RX-7 with a rotary engine in my garage, no cams there!
  • Just because it is possible doesn't make it a good idea.

    Many engines are interference engines, where the valves sweep through the same space of the pistons during different parts of the cycle. This is largely due to the need to have high compression ratios (IC engine efficiency is strongly driven by compression ratio). Timing is crucial - if the timing is off, valves crash into the pistons and your engine tears itself to pieces. Timing belts, chains, or even gears are used to prevent this. It is particularl

    • The digital solution introduces at least two and possibly more points of failure per piston Loose or frayed wire? *BOOM* - destroyed engine. Mechanical failure of a single lifter? *BOOM* - destroyed engine.

      Not likely. Why? Most likely scenario is that the valve is opened via electronics and closed via a spring. Failure == closed valve. No permanent damage.

      • The digital solution introduces at least two and possibly more points of failure per piston Loose or frayed wire? *BOOM* - destroyed engine. Mechanical failure of a single lifter? *BOOM* - destroyed engine.

        Not likely. Why? Most likely scenario is that the valve is opened via electronics and closed via a spring. Failure == closed valve. No permanent damage.

        OK, maybe you can build around interference issues. You still have many more points of failure that can leave someone on the side of the road with a dead engine, and a more complicated system to diagnose and repair (read $$$). Where is the gain?

        As it is, crank angle sensors, O2 sensors, ignition timing sensors, are all items that can and do fail which will effectively brick your vehicle or require costly repair to pass emissions inspection. Emissions laws effectively mandate these technologies, and admitte

        • > Where is the gain?

          The gain as a few people have pointed out so far is that with an electronically actuated valve that both opens and closes electronically, you can reach much higher RPMs without the "valve float" of current valve trains, where the spring can't push the valve closed in time. horsepower being related to (torque)X(rpm), this translates to greater performance.

        • You still have many more points of failure that can leave someone on the side of the road with a dead engine, and a more complicated system to diagnose and repair (read $$$). Where is the gain?

          Power, economy and perhaps maintenance costs (no need to replace those timing belts) . Do you need any more?

          Furthermore, it's probably easier to diagnose since the on-board electronics can monitor the condition of the solenoids.

  • The forces involved in a valvetrain, coupled with the speed of operation needed are going to call for some chunky power electronics driving the valve actuator solenoids. Given that the typical failure mode for power MOSFETs is to go short circuit, this would drive the affected valve wide open and hold it there. The open valve then gets bent over and possibly driven through the top of the piston.

    I can't ever see this kind of high power (multiple kW), high speed electronic switching system being as reliable a

  • No, wait... We're already talking about cars... Hmm, where does one go to for an analogy when the subject is already cars?
  • by Anonymous Coward on Tuesday February 16, 2016 @08:06PM (#51523811)

    http://www.motorauthority.com/news/1101737_video-shows-inner-workings-of-koenigseggs-camless

  • The engine is just a constant-load, constant temperature (once it warms up) generator to top up the battery. Any adaptation to power demand should be handled by the electric drivetrain.
  • Lots of discussion about what happens with a mistimed valve in an interference engine. It's a valid concern, but as has already been pointed out, happens a lot in regular camshaft engines also. The most trivial example is a broken timing belt.

    Someone mentioned that electric valve actuators could be less forceful than a mechanical valve train, so that the piston slamming against an open valve would be bad but not catastrophic. But valve springs tend to be pretty strong, so it'd take lots of force to open

  • Go buy the solenoids with the required lifetime specs. What do you figure, 10,000 operating hours per year, 100000 rotations per hour, a valve opening every other rotation?

    That's 10M actuations per year. An engine is good for about 10 years, 100M actuations. 16V per engine (or so), so you need on average 1 failure or less per 16V per 100M actuations.

    Now go price that out and I think you'll find the reason why we don't do it this way to be obvious.

    Or just ask anyone who has had a fuel injector replaced and r

  • why are we still burning fossil fuels for transportation anyway?

  • by wakeboarder ( 2695839 ) on Wednesday February 17, 2016 @12:45AM (#51525317)

    I designed some spacecraft. We were limited on what we could use for a microprocessor because we needed something with history. We almost used an 8051 variant. Same goes for engines, lets say you invent an awesome engine, it even makes you toast in the morning amongst other great things like saving you fuel. You take it to one of the manufacturers, and they love it, because it saves their customers fuel and it give them more incentive to buy their products. Then they tell you, we have these things called warranty's that we offer on all of our vehicles can you tell us the MBTF? Most of the parts are new so you go back to your lab and run it for 5-10 years.

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