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Anecdotally, I never got into drones because of the batteries. Everyone I met that had them absolutely loved them, but had like 4 batteries they needed to keep

• nostalgk 7y ago
  This. I recently worked with a company that produces drones among other things, and spoke with the head of research there. More or less, they said they had given up on putting money into drone R&D until battery technology caught up, as they had plenty of ideas that they believed in but were unfeasible due to battery life.
  • libria 7y ago
    As RC vehicles {car|helicopter|plane} get larger they reach a certain mass where liquid fuel - usually a petroleum - is preferable to battery. Why is this not an alternative for drones?
    • terravion 7y ago
      Indeed this has been done since WWI. https://www.warhistoryonline.com/military-vehicle-news/short-history-drones-b.html https://www.warhistoryonline.com/military-vehicle-news/short...
      • libria 7y ago
        Let me rephrase: why would companies consider battery life a limit when liquid fuel is a viable way forward for range, time-aloft or size?
        • guelo 7y ago
          Nobody wants to risk the liability and noise of a flying lawnmower.
        • s1artibartfast 7y ago
          Repeating my post above: Given the line of sight limitation for drones, gas power does not add much value. Batteries are usually sufficient to map/photograph the area within range of the operator. Given this legal limitation, it is often more economical to hire a small plane like a Cessna with an avionics package and a 400 mi range.
        • buran 7y ago
          And then use it for what? They exist, but they are expensive. https://www.youtube.com/watch?v=wS0Hr2lw604 https://www.youtube.com/watch?v=wS0Hr2lw604
    • colechristensen 7y ago
      It certainly has been done, and on small drones too.
    • desdiv 7y ago
      It's been done, but it's expensive. Not many people can drop $30,000 on a drone: https://www.bhphotovideo.com/c/product/1416171-REG/walkera_ql1200_hybrid_version_petrol_electric_hybrid_drone.html https://www.bhphotovideo.com/c/product/1416171-REG/walkera_q...
      • cameldrv 7y ago
        It's hardly $30k to buy a gas drone. You can buy a Cox .049 engine for $50 or so. You're looking at a fixed wing aircraft though with one of those. What's made the quadcopter drone possible is the high torque and instantaneous throttle response of small electric motors, combined with fast control electronics. The conventional way to fly a small helicopter is just like a full sized helicopter, with a main rotor and a mechanical swash plate. With the right control electronics, these can easily be made into drones, but people tend to not like them as much anymore because they're mechanically complex and finicky. The electric motors are simple, and when one goes bad you just drop in a new one.
        • twic 7y ago
          Could you couple one of those engines to a generator, and use that to power the electric motors? You'd need a battery or supercapacitor to handle change in throttle demand that outpaces generator response too.
          • jsjohnst 7y ago
            Weight is the limiting factor. Try to find a generator that can output up to 400amps at 25V (what my big drone draws) and yet weighs less than five pounds including fuel. I think that’s a more impossible goal than increasing power density in batteries is.
            • danmaz74 7y ago
              400 ampere??
          • yardie 7y ago
    • fma 7y ago
      I've watched people fly RC airplane and helicopters with gas engines. They still exist, and there are air fields for them. I've seen them since the 90s as a kid. They aren't expensive but, are bigger and require an actual landing and takeoff area. https://www.hobbytown.com/gas-rc-airplanes/c7574 https://www.hobbytown.com/gas-rc-airplanes/c7574
      • TylerE 7y ago
        Those aren’t usually gas, but rather a nitromethane mix, runs off glow plugs (saves all the issues of timing, spark plus, distributors...)
    • m-ee 7y ago
      Controls are more complicated if you're not using electric motors where a microcontroller can easily adjust the RPM. Someones already linked a hybrid drone with a gas powered generator but it's not cheap. In high volume it could probably come down a lot but I don't know how much demand there is for it.
    • bluescrn 7y ago
      The electric motors used can change the speed of 4+ independent propellers extremely quickly. This is hard to do with petrol engines, without costing a lot of extra weight or mechanical complexity, in a system where any single failure means a crash
      • scotty79 7y ago
        I wonder if there's some simple variable transmission that could be electronically controlled to deliver power from the motor to the propellers in highly controlled fashion.
        • ahartmetz 7y ago
          A generator and four motors. Efficiency would probably be around 70%. It's about 90% in diesel-electric locomotives where more weight and money is spent on efficient conversion hardware.
          • scotty79 7y ago
            That adds weight of 4 beefy electric motors to the system. There's differential based continous variable transmission that varies according to resistive torque on a control shaft: https://makezine.com/2012/08/10/lego-continuously-variable-transmission/ https://makezine.com/2012/08/10/lego-continuously-variable-t... This might enable electronic control witout using any motors just one simple coil per propeller. Energy generated through this way of control could be stored to power onboard devices.
• deleted 7y ago
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• ghaff 7y ago
  Even more generally, when I've thought about getting a drone, I imagine flying it around my house a few times, take some video, and then what? I don't really want to take it out into nature environments. That seems obnoxious where it's even allowed. I suppose I could find clubs that fiddle with the things but I don't really have the interest. So, basically, I have trouble imagining how I'd use them for more than a couple days.
  • driverdan 7y ago
    I have a DJI Spark. It's loud when it's close but as soon as it's a few hundred feet away you can barely hear it. I primarily use it in nature and usually use it at 200-400ft elevation. At 200 ft it's quieter than standing next to a running car. At 400 ft you really have to try to hear it.
    • reaperducer 7y ago
      It's loud when it's close but as soon as it's a few hundred feet away you can barely hear it. If you're in an open area. And if there is only one drone. A couple of years ago I was in a serene canyon in Utah enjoying the peace and watching nature when three drones decided to scare away the bighorn sheep. People don't hate drones because they hate drones. That's why many seem to like the idea of Amazon/UPS drone deliveries. They hate drones because of what the drone pilots do with them.
    • deleted 7y ago
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    • caconym_ 7y ago
      "Quieter than standing next to a running car" isn't a good criterion for subjecting strangers to noise in a public place they're probably visiting at least in part to get some quiet and seclusion. I don't mean to be a dick; I've been flying R/C for ~25 years and I know how difficult it can be to find fun places to fly and how frustrating when other people get in the way of that. But I also really appreciate quietness and because I live in a city it's a rare gift for me when I do get out into nature. Please have some consideration for others and don't unilaterally decide what noise level is acceptable for them unless there are already significant sources of noise present or you're really sure nobody else is around.
• cr0sh 7y ago
  Longer flight times are possible, if an engine is used instead (plus servos to change prop pitch). I'm just not sure why it hasn't been pursued much (can't be the noise - electrics aren't exactly silent)...
  • foobarian 7y ago
    People have used fuel-powered drones extensively before Li-Po batteries got good (including me). My take on why they haven't taken off as much as the modern quadcopters: they are quite a bit scarier. The main two types of flier before quadcopters were fixed-wing model airplanes, and helicopters. They are both riskier to use than quadcopters: fixed wings can't be stationary and need a large area to fly around, while helicopters have large dangerous blades. This is why either of these are less attractive to the mass market. On the flip-side, I think converting a quadcopter to use an engine is expensive because controlling 4 blades at once is not as simple as with 4 electric motors. Either they need to have 4 gas engines (expensive, not as responsive as electrics) or they need to have a variable pitch mechanism (now you need an intricate/expensive mechanical system of levers and servos to transfer the control).
    • lozaning 7y ago
      Curtis Youngblood, the OG Heli god himself, actually has 2 stroke collective pitch drones: http://www.curtisyoungblood.com/platforms/tdp-mr/ http://www.curtisyoungblood.com/platforms/tdp-mr/ It's a scaled up version of his stingray.
  • ActorNightly 7y ago
    It has, just in the form of Helicopters. Its been known for a while that moving a lot of air slowly with a bigger blade is more efficient than moving less air faster with 4 props. The issue is that stability and control is easier to do with 4 blades rather than with one that has a swash plate.
• driverdan 7y ago
  It depends on how you use them. I travel full time so I primarily use mine for nature photography. 15 min is usually plenty of time and if not I have a 2nd battery that takes no time to swap. It would be nice to have longer battery life but it's not a deal breaker. The only cases where needing more time would be a big deal would be for filming something that lasts longer than the battery.
• coin 7y ago
  With petrol’s energy density, why not make gas powered drones? Gas engine → generator → small battery (backup power) → electric motors. This is what manned drones (still in development) do.
  • i_am_proteus 7y ago
    Great idea if you have robust controls! Terrible idea if you don't, because a crash can handily result in a fire or an explosion.
    • dredmorbius 7y ago
      Heavier fuels (kerosen, a/k/a jet fuel, diesel) have equivalent energy density to petrol, but are far less flamable. You might get a small fire, but not an explosion. And there are a lot of RC aircraft already. They are noisy, however. Drone buzz now is simply from spinning fans. Adding a reciprocating motor to the mix is all the louder. The alternative is lighter airframes and solar power. For quads / octos, probably not viable, but for a prop-driven fixed-wing craft, a very small amount of thrust to counter gravity could be quite effective. Expanded polystyrene or similarly light body, solar cells over all horizontal surfaces, and an ultra-lightweighted controls and imaging payload. That would allow for long-duration flights at least in daylight. The low-energy use would also make battery-powered night flights more viable, certainly beyond 15 minutes. The principle cost is loss of hover capabilities.
      • i_am_proteus 7y ago
        Yes, but the motor (turbine) to run kero is more expensive than the motor (piston) to run petrol.
        • grogenaut 7y ago
          The motor to run the drones was expensive till they became mass produced and dropped in price. Same for the batteries. DJI Drones aren't exactly cheap either. also I believe if you want to be pedantic, if it runs on combustion it's a engine. if electric then a motor.
• macintux 7y ago
  For me, it’s the FAA notification requirements that seem daunting. It looks like the situation may be better than it used to be, but it’s still confusing at a glance.
  • jsjohnst 7y ago
    Get your Remote Pilot license and you’ll understand that process inside and out.
• deleted 7y ago
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• LeftHandPath 7y ago
  I never got into them for the same reason I never got into football or (before I had to for professional reasons) Linux - everyone who is into it turns it into an evangelism project. I’m sure I would love them if I tried them, but I don’t want to be seen as the type of guy who owns a drone (like how I don’t want to be known as the guy who uses Linux or the village Libertarian, even though those words might describe me reasonably well).
• RRRA 7y ago
  Seems like graphene batteries are just around the corner and safer than lipo, with a few time the charge, that'll be interesting to see!
  • test1235 7y ago
    Seems like graphene has been around the corner for a decade or more - are there any real world applications yet?
    • mothsonasloth 7y ago
      Suncream (sunscreen)