So, I get that so far this is just an Amazon publicity stunt and there isn't actually anything here to talk about.
But give them some credit. Most of these problems are solvable. You can build a drone with bumpers around the propellers and screens above and below, to solve the "sticking finger in the propellers" problem.
You can deal with the vast majority of the navigation problem by just getting enough altitude. Above a certain altitude, you don't suddenly see new unknown buildings springing up out of nowhere, and don't need to worry about navigating around power lines or anything of the sort. Just do the takeoff in a controlled area, rise up to an altitude high enough to avoid anything but a few pre-programmed skyscrapers and radio towers, and fly to your destination at that altitude.
And you can solve the landing problem by having someone sit in a control room and take over for the landing and takeoff from customer locations. Paying someone for two minutes worth of landing and takeoff is much cheaper than paying them for the full 30 minute delivery time, along with the expense of a full sized vehicle and insurance that goes along with it.
Everyone seems to worry about the liability aspect, asking "what happens when one of these falls on someone". But we already deal with liability issues with cars all the time. Heck, we deal with the issue with planes as well; planes do sometimes fall out of the sky and kill people, but you don't hear people saying that delivery by plane will never work. That's just built into the cost of delivery. Drones are much lighter, don't have tanks of gasoline, and flying in the air gives you much more open space than driving on roads. And you could probably add a failsafe that deploys a parachute if the drone loses power or otherwise start to fall.
The big problem is flight time. Batteries just don't have the energy density to support long flight times; you can build ultra-light drones that get an hour of flight time with a lot of care, but if you're building something that's actually going to carry packages, deal with wind, and so on, 30 minutes is probably the upper limit. That means that you won't be able do trips of more than about 15 minutes each way. Now, since you can go in a straight line, without traffic, that gets you further than a 15 minute car/bike delivery, but it'll still be limited to people who are fairly close to a distribution center.
Are there other types of drones other than traditional quadcopters, for example variable-pitch quadcopters [1], that can get more airspeed and thus cover more distance in 15 min?
What about using airplane-style drones (like traditional RC planes) + a parachute to land the package? And this way you could use nitro gas fuel to get better energy density (since you can use one big gas engine instead of having to use four tiny motors)
I have quite strong opinions about this. The only way to ensure efficient, high-load drone flight is to develop a hybrid design which uses wings to generate lift during cruise. The efficiency lost to the rotors is massive.
So I think eventually we will see tilt-rotor designs, where wings take over once the drone is airborne but the rotor disk is pitched horizontal for takeoff and landing. This massively increases energy efficiency, and makes it possible to go a lot faster.
The reason this hasn't been done with larger airplanes (the only prominent example, V-22 Osprey, demonstrates the difficulty), is that combustion engines makes the design prohibitively complex. But with electric motors, it should be very doable.
Wow, that's with a greater degree of mechanical simplicity than I thought possible. But this is exactly what I was talking about. Now if you can somehow reduce propeller drag at high horizontal speeds and also accomodate a payload and/or a larger battery and also handle adverse wind conditions, you'd have something really nice.
Sure, there are potentially other designs that will get somewhat higher speed, though at some point that will require enough extra power that it won't be worth it.
Airplane style drones can fly further, but navigation is more difficult, and parachutes will pose a lot more logistical problems than landing quadcopters (or, more accurately, multicopters; they used octocopters in the demo). One of the nice things about multicopters is how easy control and navigation systems are compared to something like an airplane or traditional helicopter.
The biggest improvement would be from better battery technology. Battery technology is improving, but very slowly compared to, say, transistor density.
Comments
So, I get that so far this is just an Amazon publicity stunt and there isn't actually anything here to talk about.
But give them some credit. Most of these problems are solvable. You can build a drone with bumpers around the propellers and screens above and below, to solve the "sticking finger in the propellers" problem.
You can deal with the vast majority of the navigation problem by just getting enough altitude. Above a certain altitude, you don't suddenly see new unknown buildings springing up out of nowhere, and don't need to worry about navigating around power lines or anything of the sort. Just do the takeoff in a controlled area, rise up to an altitude high enough to avoid anything but a few pre-programmed skyscrapers and radio towers, and fly to your destination at that altitude.
And you can solve the landing problem by having someone sit in a control room and take over for the landing and takeoff from customer locations. Paying someone for two minutes worth of landing and takeoff is much cheaper than paying them for the full 30 minute delivery time, along with the expense of a full sized vehicle and insurance that goes along with it.
Everyone seems to worry about the liability aspect, asking "what happens when one of these falls on someone". But we already deal with liability issues with cars all the time. Heck, we deal with the issue with planes as well; planes do sometimes fall out of the sky and kill people, but you don't hear people saying that delivery by plane will never work. That's just built into the cost of delivery. Drones are much lighter, don't have tanks of gasoline, and flying in the air gives you much more open space than driving on roads. And you could probably add a failsafe that deploys a parachute if the drone loses power or otherwise start to fall.
The big problem is flight time. Batteries just don't have the energy density to support long flight times; you can build ultra-light drones that get an hour of flight time with a lot of care, but if you're building something that's actually going to carry packages, deal with wind, and so on, 30 minutes is probably the upper limit. That means that you won't be able do trips of more than about 15 minutes each way. Now, since you can go in a straight line, without traffic, that gets you further than a 15 minute car/bike delivery, but it'll still be limited to people who are fairly close to a distribution center.
Are there other types of drones other than traditional quadcopters, for example variable-pitch quadcopters [1], that can get more airspeed and thus cover more distance in 15 min?
What about using airplane-style drones (like traditional RC planes) + a parachute to land the package? And this way you could use nitro gas fuel to get better energy density (since you can use one big gas engine instead of having to use four tiny motors)
[1] http://www.youtube.com/watch?v=Vy5Ky50eGJs
I have quite strong opinions about this. The only way to ensure efficient, high-load drone flight is to develop a hybrid design which uses wings to generate lift during cruise. The efficiency lost to the rotors is massive.
So I think eventually we will see tilt-rotor designs, where wings take over once the drone is airborne but the rotor disk is pitched horizontal for takeoff and landing. This massively increases energy efficiency, and makes it possible to go a lot faster.
The reason this hasn't been done with larger airplanes (the only prominent example, V-22 Osprey, demonstrates the difficulty), is that combustion engines makes the design prohibitively complex. But with electric motors, it should be very doable.
There is an RC model called the Quad Shot that sounds similar to what you're describing. http://www.youtube.com/watch?v=IK_-yTrwNtU
Wow, that's with a greater degree of mechanical simplicity than I thought possible. But this is exactly what I was talking about. Now if you can somehow reduce propeller drag at high horizontal speeds and also accomodate a payload and/or a larger battery and also handle adverse wind conditions, you'd have something really nice.
Sure, there are potentially other designs that will get somewhat higher speed, though at some point that will require enough extra power that it won't be worth it.
Airplane style drones can fly further, but navigation is more difficult, and parachutes will pose a lot more logistical problems than landing quadcopters (or, more accurately, multicopters; they used octocopters in the demo). One of the nice things about multicopters is how easy control and navigation systems are compared to something like an airplane or traditional helicopter.
The biggest improvement would be from better battery technology. Battery technology is improving, but very slowly compared to, say, transistor density.
It's a way to take the wind of of Google's sails when they announce delivery by self-driving car, which would have seemed futuristic until now.
Strange that this was downvoted given that it was proven true onto a couple of days later.