Mavic Mini - Inspections

[tpodm]

So I have this potential job wanting to view internals of an air duct. The duct has a diameter of 900mm which means the mavic mini will fit in there but main concern is would it be possible to fly the drone through the duct work. Anyone have any experience with this?

Thanks.

 

[Starz]

Watching.

 

[old man mavic]

me too

 

[Meta4]

So I have this potential job wanting to view internals of an air duct. The duct has a diameter of 900mm which means the mavic mini will fit in there but main concern is would it be possible to fly the drone through the duct work. Anyone have any experience with this?

What is the duct made of and will it be dark inside?

 

[tpodm]

Going to site next week to have a site inspection, but i am assuming it will be (fingers crossed) stainless steel.

Yes it will be dark inside but we can light it up inside with a flood light.

 

[Meta4]

Going to site next week to have a site inspection, but i am assuming it will be (fingers crossed) stainless steel.

Yes it will be dark inside but we can light it up inside with a flood light.

Anything metallic, even thin foil will block GPS so the drone would try to use VPS for positioning.
If the duct is too dark or if there is no recognisable pattern or tecture to the bottom surface of the ducting, the drone would be in atti mode without brakes or position holding.
Will the mini even launch without GPS and VPS?

 

[rehkram]

This may not end well. Those tolerances are too tight for the MM. It can, probably will, drift sideways, whereupon unless you have nerves of steel it is all too easy to over-correct and crash into the opposite wall.

Second prediction, it will ascend if, or rather when, it senses the bottom of the duct and will shoot up and try to glue itself to the ceiling. You could tape over the sensors to avoid that one. See FlytPath's youtube for a full discussion and demo.

I know these things from direct experience of flying the MM in tight places. I'm comfortable with 2 meters clearance in all directions but will get closer if the nose is pointing at an obstacle and the FPV is clear. Otherwise, it's not the right tool for the job. There's a good reason there aren't, to my knowledge, any youtube videos of flying an MM inside ductwork!

 

[RogerDH]

Maybe an RC car would be a better option?

 

[scro]

Sounds like it could be very challenging. As other have said, you'll be up against:

• No GPS inside the duct
• Not enough light for optical sensors to work. Probably no detail on the duct walls either for the sensors to detect
• No light for the camera to take good video/stills. A flashlight might help but the light would be very much side-on and not illuminate the sides of the duct. If the duct isn't straight it wouldn't work after the 1st bend either.
• Turbulence created by prop wash and any draught in the duct would make flying in atti mode very hard, especially as you can't see the drone, or see it very well.
• Risk of drone sucking itself to the ceiling of the duct
• Drone camera will probably be too close to the subject and hence be out of focus.

How about a cellphone on a long stick or selfie pole, or strapped to an RC car, as RogerDH suggests? At least the phone has a camera light. I've used the long stick method to do inspections under floors and similar tight spaces with good success. Just start the video recording, with the flash on, and poke the phone/stick in to the space to be inspected. It can take a couple of goes to get just what you want to see.

Flying a drone up a duct sounds advanced and exciting, but there are other simpler, cheaper, lower risk, (and more boring?) ways of carrying out the inspection.

 

[Lurch003]

Sounds like you need one of these !!

 

[ff22]

Watching.

With or without popcorn?

 

[rehkram]

Here's the FlytPath video, well worth watching for general information, but particularly if you want to fly indoors and/or in tight places.

 

[Thanev]

Sounds like you need one of these !!

View attachment 102935

But business will suffer when he goes back to school....

 

[Lurch003]

??? I meant the ATV not the child !!!

 

[rehkram]

I've flown the MM inside our empty concrete corn silo. It's around 20 feet in diameter and 100 feet high. Hand launch through an access door, center drone, go up, look down, take photo, descend, hand catch. Making corrections just going straight up and down a 20 ft wide tube is easy enough.

Here's the view looking down. You can see my hands, the controller display and a pigeon nest above me with two eggs at 6 o'clock center. I did not know the eggs were there until I looked at the captures afterwards. This was taken mid-March, the chicks fledged successfully and have joined their flock mates learning how to precision-poop on my tractor.

 

[Rondal]

Put a string on it (that way you can get it back- maybe) and give it a try.

 

[Thanev]

??? I meant the ATV not the child !!!

Don't knock it.These young one's have serious skill sets with a controller.

 

[Lurch003]

Don't knock it.These young one's have serious skill sets with a controller.

To be honest, he'd fit in the ducting! Job done for a bag of sweets ?

 

[Bosco Bear]

If it's dusty in the ducts, the dust will get blown all over the place and could cause problems with the drone -- motors, gimbal, electronics, etc. As previously mentioned, something with wheels is a better alternative.

 

[old man mavic]

maybe something with "ducted" fans would work ,like a hovercraft