Drones

NOVAerial's helicopter drones: Better than multicopters?

NOVAerial's helicopter drones:...
NOVAerial Procyon 800E: all the advantages of a multicopter with added endurance, lifting power and autorotation?
NOVAerial Procyon 800E: all the advantages of a multicopter with added endurance, lifting power and autorotation?
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NOVAerial Procyon 800E: all the advantages of a multicopter with added endurance, lifting power and autorotation?
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NOVAerial Procyon 800E: all the advantages of a multicopter with added endurance, lifting power and autorotation?
NOVAerial Procyon 800E: nearly two metres of blade diameter makes these a large and heavy airframe
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NOVAerial Procyon 800E: nearly two metres of blade diameter makes these a large and heavy airframe
NOVAerial Procyon 800E: top speed of 90 km/h and a telemetry range of 20 km
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NOVAerial Procyon 800E: top speed of 90 km/h and a telemetry range of 20 km
NOVAerial Procyon 800E: tail rotor is controlled by a separate motor; there's no drive shaft down the tail
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NOVAerial Procyon 800E: tail rotor is controlled by a separate motor; there's no drive shaft down the tail

In our rush to accept multicopter drones into our world, have we forgotten the advantages of the humble helicopter? One Canadian company says its single top rotor helicopter drones are as stable and easy to fly as a multicopter, but with several key advantages.

Multicopter drones have emerged in the last five years as one of the key technologies shaping our immediate future. Their easy, stable flight and ability to hover gives them a ton of use cases from filmmaking, to deliveries, industrial inspection, construction and even transport, some time in the future.

But one Canadian company believes that in all the excitement about drones, we've forgotten about the humble helicopter – and a few key advantages a large single rotorcraft has over a multicopter once the latest electronics are figured in.

Helicopters, with their slower-turning single rotor, use less power to develop lift than a multicopter, which gives them a superior ability to carry heavy payloads, as well as longer endurance in the air. They're capable of stable flight in much higher winds than comparably sized multicopters, they're more efficient at high speeds, and they fold up quickly for easier transport than most multirotors.

Perhaps one big reason why they're not more popular is the perception that they're much harder to fly than a multicopter, but this is no longer the case. In fact, in full manual mode where a user has individual control over all rotor speeds, a helicopter is much simpler to fly than a multicopter.

What makes multicopter drones so stable in flight is the use of highly sophisticated flight computers that take the pilot's intention at the sticks and consider a bunch of sensor and GPS data to micro-manage the speeds of the motor controllers. Modern helicopter drones have all the same gear in them, allowing things like stable GPS hover, return to home functions and a much, much less complicated experience behind the sticks. You can set a modern heli's controls up to work almost exactly like a multicopter if you like.

With that in mind, there are some drawbacks. Larger rotors, for example, make more noise, and they're very sensitive to balancing issues and minor crash damage that might not ground a multicopter. On the other hand, that larger top rotor can autorotate the thing to the ground in the event of a motor failure, so there's a reduced risk of simple fall-out-of-the-sky damage to your airframe and payload.

NOVAerial Procyon 800E: nearly two metres of blade diameter makes these a large and heavy airframe
NOVAerial Procyon 800E: nearly two metres of blade diameter makes these a large and heavy airframe

Either way, NOVAerial Robotics has announced that its Procyon 800E drone helicopter is now flight tested and ready to begin limited series production.

The 800E is no hobbyist machine – it weighs in at 12.4 kg (27 lbs), has a 1.78 meter (5.8 ft) main rotor diameter, and carries a payload of between 1 and 5 kilos (2-11 lbs). It'll hover for 40 minutes, or cruise at 50 km/h (31 mph) for 50 minutes, and its top speed maxes out at 90 km/h (56 mph). Telemetry range is up to 20 km (12.4 mi) – this is a serious piece of kit.

Its 3D-printed modular body is simplified with the use of a separate motor for the tail rotor, eliminating the complex driveline and gear systems typically used to feed power from the main motor down the tail shaft. And the helicopter is controlled by Ardupilot autopilot software, allowing 90 percent of the automation you're familiar with on a multicopter drone.

No pricing is available, but it'll certainly be interesting to see if helicopter style drones start making a comeback now that multicopters have blown the doors open to so many industrial, creative and forward thinking applications.

More information: NOVAerial Robotics

10 comments
tapasmonkey
Drawbacks also include the potentially lethal rotor. Hit someone with a drone, maybe they'll sure you. Hit someone with one of these, you're likely going to prison.
JoelTaylor
Another draw back of the single rotor is that they are much more mechanically complex and that makes them more susceptible to mechanical failure. The mutirotors for their short comings are mechanically simple, having nearly all their complexity in the flight control computer which has no moving parts.
Bob
I have wondered why it took so long to add stability control to the helicopters. A large rotor is so much more efficient than several small ones giving them more lift and much longer flight times. Fixed wing drones also have superior range and endurance for many applications. But for photography and a stable platform the multi rotors are king. Since the simplest way to increase performance is to increase rotor diameter, it will be interesting to see how the multi rotors evolve.
Bob Stuart
I can't see any reason for a single rotor to automatically have a lower disk loading than a multi-rotor; that's a design decision. The single rotor has to carry ballast in the leading edges, where the multi rotor can use a rigid connection to the hub to maintain angle of attack. Auto-rotation is nice, but a parachute is probably lighter. Even motor cooling gets easier with multiples, and the reliability eliminates the very heavy interconnection between engines needed for safety on mechanical multi-rotors.
Joe Blough
One huge advantage of a single rotor machine is that you can power them with GASOLINE engines. Gas engines don't respond quickly enough to enable them to be used on multicopters, they simply can't be controlled fast enough for stability. However, on a single rotor machine you can load it up with gas and fly for hours not minutes while carrying substantial loads. Until battery technology improves a huge amount, multicopters will be short duration short range toys compared to anything powered with gas engines. I recall gizmag having a piece on a multicopter that has a central gasoline engine driving a generator which in turn charged batteries and powered the electric motors. This has a great range and duration too. So my fellow geeks, back to the past if you want a serious platform that can stay aloft and carry big weights.
Paul Anthony
"Larger rotors, for example, make more noise, and they're very sensitive to balancing issues and minor crash damage that might not ground a multicopter. " So there you go!
MD
I think this article is oversimplifying things a lot.. Noise, balance and crash tolerance... If you are comparing a toy Multiciopter with an "Industrial" RC Helicopter, there is no comparison. Helicopters are aerodynamically far superior to FIXED Pitch multicopters.. For large rotary wing aircraft, Balance and damage resulting from any kind of "crash"are equally significant, in actuality, IF you are operating any RC Aircraft Professionally (Making it a UAV), you do not want to have any kind of "crash" because CASA / CAA/FAA are all very interested (mandatory reporting) in anything which affects safety of operating Aircraft. However a conventional tailrotor Helicopter, just like a multicopter, is not the Ideal aircraft for all operations, designers and developers just have to look outside the box... There is an optimal configuration for any given task-set. PS, a Flybarless helicopter, has a similar number of interconnections and points of failure as a hexacopter, (Similar redundancy too - NONE) . NB there is no such thing as manual control of either a multicopter, or a "flybarless" helicopter, If the flight controller fails, your aircraft is going down. Reliability of electronics is likely to be similar, afterall they are using the exact same control hardware as used in a lot of multi's. The "Professional" Multicopter crowd are often composed of people who have never been exposed to anything else, and often aren't hobbyists first and professionals second, they are more often "photography driven" and have little interest in the actual art of the flying machine (or the science behind it). I do realise that most of the people reading and commenting here are merely casual bystanders and know nothing specific to most of the fields they are commenting on. General consumption only, do not use such an article as the basis of your purchasing decisions. ()
RobertLefebvre
Hello All, Thanks Mr. Blain for the article on the Procyon helicopter. I'm glad to see that you read much of the material on my website and produced a well informed article. I do believe that conventional helicopter systems have been overlooked in the rush to jump on the multirotor bandwagon. Many people do not realize that they can be as easy to fly as a multirotor. They're all just flying robots, and can use the exact same control systems. Meanwhile, helicopters present some important advantages over multirotors for medium-range professional applications. I'd like to comment on a few of the comments here. As regards safety relative to multirotors, you have to be sure to compare like-sized machines. I can assure you, having flown very large multirotors, that they are equally dangerous. Comparing them is like arguing about if you will be "deader" after being struck by a sword, or multiple knife wounds. Helicopters are undoubtedly more mechanically complex than multirotors. This is one of the main advantages of multirotors. They are simple and robust, hard to damage, easy to repair. But in applications where their typically low speed, short duration flight is not adequate, helicopters are a sometimes the only option. Also, while they do have more moving parts, helicopters are very mature technology. The Procyon 800E was specifically designed to eliminate as many unnecessary mechanical complexities as possible. It didn't actually take that long to add stability control to helicopters, I've been developing the technology right alongside multirotors for 6 years. It just appears that it has lagged, because not many people are working on helicopters and multirotors dominate the "drone" landscape. This is mostly because of the simplicity and robustness of multirotors. They are ideal for developing flight software, both because they are crash resistant, and typical computer science types would struggle to build and repair a helicopter. While there is no natural law stating that helicopters would have lower disk loading than multirotors, I think you will find this to be true if you really do an engineering study on these various systems. A helicopter has one core powertrain, battery mounting, payload and flight control frame, with a single boom for the tail rotor. The weight is essentially hanging from a shaft, and the large rotor is self-supporting via centripetal force. Multirotors necessarily have a central frame for battery and payload, and then one boom per disk, where the boom must be strong enough to withstand the load and vibration it is exposed to. Add up the weight of these booms, with a relatively small disk area, and you'll see it's difficult to achieve a lower disk loading than an optimized helicopter. I agree, that the ease of applying a gas engine to a helicopter is the "killer app" in the UAV industry. This is an easy, and very affordable way to achieve a high performance VTOL aircraft with multi-hour range. And again, unlike fuel-cells, this is very mature technology, and very very low cost. I have a development mule gas helicopter with 1.5 hour duration, which could easily become 3-4 hours if I wanted. Capable of 120 km/h flight speeds and lifting 3kg payloads, it completely eclipses any of the systems that Amazon and others have proposed. MD - excellent comments, I agree.
fb36
Not talking about these but I remember an episode of Mythbusters. They first tried an experiment with a gas powered RC Helicopter. Even the expert they brought from the store couldn't make it hover and it crashed dangerously. But they easily used a drone later.
over_there
A helicopter is superior to a quadcopter in every way. Quadcopters only got so popular because the hobbyist building them put a lot of effort into the stability systems in them they were electronic s projects which made them easy for someone with no idea to fly one.