jlcortex · HackerTrans

That is true for HYBRiX, but there are other hybrid multirotors, which do not have a design well-balanced enough to being able to stay aloft on just batteries (batteries to lift a 25kg MTOW drone are heavy, so the drone needs to be very light, while still robust, to work properly.. it is tricky ;)

jlcortex

há 6 anosdiscuss

Equivalent hydrogen multirotors at this stage do not have the payload capacity of a hybrid fuel-electric drone. They might be a great solution in the future, but the technology is not there yet.

jlcortex

há 6 anosdiscuss

Sorry about that! :(

jlcortex

há 6 anosdiscuss

It's because of the duty cycle of the engine, we put it at a constant rate of 12000 RPM for hours. It is not the standard setting for that engine.

jlcortex

há 6 anosdiscuss

Yes, it is a series hybrid, the engine acts as a range-extender. The mechanics of the aircraft are much simpler this way and therefore more reliable. We are not sure about the efficiency, though. There are no helicopters under 25kg MTOW with our flight time right now.

jlcortex

há 6 anosdiscuss

Of course it does not compare to electric multirotors in that aspect, but its performance is much more advanced. We aim to replace combustion manned helicopters in first response applications, among others. HYBRiX can provide similar operational flight time with 100 times less fuel consumption per hour. Electric multirotors, with up to 30 minutes of flight time, are not suitable for searching missions for example.

jlcortex

há 6 anosdiscuss

A hybrid drone like HYBRiX has power redundancy. If the engine stops for some reason, it still has some minutes of endurance in electric-only mode, for an emergency landing. With an unmanned helicopter, if the engine fails, the crash is mostly warranted, even with the autorotation function.

Besides, the mechanics are simpler and therefore more reliable. And the propellers are smaller than a helicopter rotor, which is safer. Multirotors are also much simpler to operate than a helicopter. Most industrial customers do not want to operate unmanned helicopters because of their complexity.

jlcortex

há 6 anosdiscuss

Fix wings are amazing for some applications. The problem with them starts when you want to carry heavier payloads. Taking-off and landing gets more and more complicated as they scale-up, while you only need 10 sq. meters to take-off HYBRiX drone. In the end, the different drone types are suitable for different purposes.

jlcortex

há 6 anosdiscuss

The problem with that is that, in the end, you are carrying a multirotor on your plane. It is not so efficient as a fix-wing or plane and it does not perform like a multirotor, because it lacks hovering endurance. That convertible concept does make sense for some specific applications, but they are not the perfect-for-all solution either.

jlcortex

há 6 anosdiscuss

That's the point. Even though some fix-wings or convertible drones are able to do certain maneuvers similar to multirotors, their endurance is extremely limited then. A hybrid copter like HYBRiX is able to hover for hours, but it would be even more efficient on translational flight. Here you can see to which degree we can control the drone when we push it to its limit: https://www.instagram.com/p/CHIZgQPgLtZ/

This means an outstanding resistance to wind, which fix-wings do not have.

jlcortex

há 6 anosdiscuss

Quadcopters are equivalent to helicopters in terms of performance. VTOL-planes fly as a plane, they do not have hovering endurance, barely a few minutes at the most, just for take off and landing. So they cannot perform missions that require hovering capabilities. A hybrid multicopter has the advantage of longer-endurance, traditionally exclusive of planes, while still keeping all the advantages in simplicity, ease of use and versatility of multicopters.

jlcortex

há 6 anosdiscuss

The main reason is that multirotors are a much more recent solution, and they started as small unmanned vehicles because the regulation is much simpler (the requirements for airworthiness certification for multirotors are not standardized yet). But I believe that we will see more and more applications for multirotors in the future. As a concept, they are safer than helicopters, with much simpler mechanics.

jlcortex

há 6 anosdiscuss

Hi all! thanks for sharing the news! At Quaternium we are very excited to see that our project is raising so much interest! There are already many accurate comments on this thread. But just to give you some context. Quaternium was the first company in the world to demonstrate a hybrid power system for a drone, with a flight over 3 hours back in 2015. Right now, our latest record is over 10 hours of hovering flight with HYBRiX multirotor (with an experimental setting with more fuel and no payload). A key element of this news is that the drone is <25 kg MTOW, (bigger aircrafts have obviously longer flight times). The fuel engine acts as a range-extender, it is a series hybrid, like the BMW i3. And we develop the power system, in collaboration with Löweheiser company (https://loweheiser.com/) using a 2-stroke Zenoah engine that we adapt to the drone needs. Our product uses the engine on a very different duty-cycle, comparing to the standard application, so we do a lot of work on it and got a much better performance compared to other competitors. Multirotors are the most popular drones for several reasons, that some users have already mentioned. They are much more versatile because they can hover, do not need launching platforms and are quite easy to operate. They are also mechanically simpler than helicopters, reducing failure points. Our goal with HYBRiX is to being able to replace manned helicopters for aerial imaging operations, not to replace planes or fix-wings, which are more efficient for the applications that do not require hovering. As for convertible VTOLS / fix-wings, they are cool but not so versatile, because their hovering endurance is very limited, only useful for VTOL take-off / launch. That makes it possible to take-off from smaller areas than planes, but do not have a performance comparable to a multirotor. Hope this clarifies some doubts mentioned on the thread.