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by baybal2 2106 days ago
Single rotor controls are much, much simpler.

At least it does not require a mandatory PID control to not fall out of the sky.

Very little math involved in control of a helicopter. A 3 actuator type with 1 actuator for each axis basically has no need for any control signal manipulation, and can be made fully analog.

And a helicopter can be made more or less statically stable by pure mechanics, and aerodynamics.

P.S.

It doesn't seem that the drone in question exist in anything, but CGI at the moment.

P.P.S.

And quite unsound CG at that. On some of their CG shots, a swashplate actuators are attached with their axis coincidal with that rotor..., and a tail rotor control yoke not attached to anything...
2 comments
coolspot 2106 days ago
In my understanding Ghost 1-3 do exist, but classified.

Ghost 4 is in development/entering production. Being military project, it is likely that publishing real photos would be difficult at this stage for various reasons. Same with giving real blueprints/CAD files to a 3D artist for marketing materials.

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CamperBob2 2106 days ago
Given this, what are some reasons why single-rotor RC aircraft have never been as popular as quads?
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rasz 2104 days ago
RC Heli = expensive specialized mechanical parts, collective pitch Rotor Head is a nightmare.

quad = difficult to develop software control loop

One is easier to replicate after initial development than the other. Heli crash also usually results in destruction of Rotor Head, the most expensive part. You could use an analogy of Carburetor versus EFI.

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baybal2 2105 days ago
Single rotor crafts do not avail for plasticky parts, and require more non-off-the shelf parts in general.

Even very first quads were for example easily makeable with existing toy parts, and plastic.

But with just a bit more efforts, single rotor craft take a lead from quads by a significant margin.

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CamperBob2 2105 days ago
Interesting, thanks. I've never heard this perspective before. So you'd say that anyone building an elaborate homebrew quad -- e.g., the TechIngredients guy at https://www.youtube.com/watch?v=4ZPvZiJLbvI , who generally seems to know what he's doing -- would be better off putting comparable effort (and comparable cash) into a single-rotor aircraft instead?
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