sooo...has anyone used the power of EDF to make a truly functional RC hovercraft?

[Marzipan]

my Google-fu has shown there is a distinct lack of fully functional RC hovercraft out there and what is out there are generally pitiful examples that can only barely move on perfectly flat surfaces, I think that's due to the issue of not having motors with enough airflow and static pressure to fill the skirt, lift the craft up and keep up, and have enough air escaping the skirt slots or holes so it is actually hovering.

I have zero RC experience of any kind, so I'm totally theorizing and talking from my ass based on how I've seen aircraft perform with your standard electric motor and the jets with EDF. right now I'm only talking about having a functional skirt. the actual propulsion would be handled by one or two standard motors with or without rudders.

further to this...because TF has an awesome ease of use and low budget focus, making said hovercraft would be affordable so many could build one of their own.

has this been done already and my Google-fu failed me or is my observation right...there is a distinct lack of options and a serious vacuum in the hovercraft space?

 

[LitterBug]

EDFs are not necissarily best for hovercraft. They are usually propped for high speed, not high pressure. Squirrel cage might be a better idea for a lift fan. What you want is high volume for the lift fan, not high pressure or high speed.

 

[Marzipan]

EDFs are not necissarily best for hovercraft. They are usually propped for high speed, not high pressure. Squirrel cage might be a better idea for a lift fan. What you want is high volume for the lift fan, not high pressure or high speed.

I just looked up squirrel cage and found a fan blower. is that what you were referring to?

 

[leaded50]

https://forum.flitetest.com/index.php?threads/fpv-50mm-edf-hovercraft.62767/ ??

 

[quorneng]

Hovercraft can fall into two categories, those with a high pressure 'air curtain' and those that use a flexible 'plenum chamber' skirt that only need a low pressure but a high volume. High pressure requires some form of centrifugal fan. Low pressure can be a multibladed axial fan.

Both systems suffer from control issues due to the ease with which they can travel in any direction. This requires a fully controllable 360 degree thrust in both direction and yaw. Achieving this tends to be a bigger problem than providing the 'lift' air.

 

[PsyBorg]

Im not sure if these guys use EDF's on their gear or just souped up BDF's

 

[LitterBug]

Im not sure if these guys use EDF's on their gear or just souped up BDF's

Those use a dual discharge centrifugal squirrel-ish cage fan for lift and the forward(maneuvering) thrusters. see https://crunch.craft-tech.com/applications/design-optimization/hovercraft-fan/

 

[PsyBorg]

Those use a dual discharge centrifugal squirrel-ish cage fan for lift and the forward(maneuvering) thrusters. see https://crunch.craft-tech.com/applications/design-optimization/hovercraft-fan/

I was just tryin ta be funny... chalk up another fail haha..

 

[telnar1236]

my Google-fu has shown there is a distinct lack of fully functional RC hovercraft out there and what is out there are generally pitiful examples that can only barely move on perfectly flat surfaces, I think that's due to the issue of not having motors with enough airflow and static pressure to fill the skirt, lift the craft up and keep up, and have enough air escaping the skirt slots or holes so it is actually hovering.

I have zero RC experience of any kind, so I'm totally theorizing and talking from my ass based on how I've seen aircraft perform with your standard electric motor and the jets with EDF. right now I'm only talking about having a functional skirt. the actual propulsion would be handled by one or two standard motors with or without rudders.

further to this...because TF has an awesome ease of use and low budget focus, making said hovercraft would be affordable so many could build one of their own.

has this been done already and my Google-fu failed me or is my observation right...there is a distinct lack of options and a serious vacuum in the hovercraft space?

Another thing to keep in mind is scale. Real hovercraft need decently flat surfaces to operate on as well. Grass for an RC hovercraft would be like driving through thick foliage for a real one. It's not a one-to-one relationship for scaling ground effect and hovering height, but an RC hovercraft capable of traversing a wide range of surfaces and not just fairly smooth ones is going to essentially be a funny multirotor by that point. You can still definitely gain some benefits from ground effect and reduce the energy required for flight, and you'll get some help with stability, but ultimately what you have won't look much like a hovercraft unless you build excessively large.

Probably the most all-terrain capable hovercraft I have seen in a small RC format is this design from Peter Sripol:

FREE 3D printed RC hovercraft - YouTube

As you can see, it can go over pebbles and other small obstacles, but this is about the limit of what will be reasonably achievable with a hovercraft this size.

There is also a Flite Test Episode where Peter built something similar with DTFB:

DIY Hovercraft - One Day Projects For Snow | Flite Test - YouTube

Both of these designs use a flexible skirt which is pretty important since it allows the skirt to deform around obstacles while maintaining something of a seal and lifting the vehicle.

 

[leaded50]

i did a search on Google... a lot of ready-to-go EDF hoovercrafts, and DIY projects.