<p>I would think one of the stable platforms with obstacle avoidance would work.  DJI's newest drones have this feature although you would need to mount a very bright light on the drone for it to be useful in a dark cave.  If you're a skilled pilot then I would recommend a very powerful mid-range platform and fit a very bright LED lamp for illumination.  The DJI digital FPV system would also be essential to have if you're exploring a cave and examining the walls.  </p>

CC BY-SA 4.0
2020-04-15T02:54:04.557Z
Does the DJI flight software even work in situations where neither the GPS nor the cameras are available?
Mark
CC BY-SA 4.0
2020-04-16T03:52:24.607Z
@Mark  You are probably correct that the DJI drone would probably not want to fly without having a gps signal.
tavis
CC BY-SA 4.0
2020-04-16T06:54:59.347Z
The DJI digital system (or, rather, its goggles) is rather bulky, though, and that's a major drawback in caves where you must oftentimes squeeze yourself through very tight passages.
FlashCactus
CC BY-SA 4.0
2020-04-15T02:39:50.447Z
2020-04-21T03:56:21.240Z
2020-04-21T03:56:21.240Z
tavis
<p>Flying in this sort of environment needs to be <strong><em>very</em></strong> carefully planned + controlled.</p>

<p>The radio frequencies typically used for drone control + video transmission are extremely poor at penetrating any thickness of rock. </p>

<p>Unless you're always able to keep to a very clear line of sight, I think you would be getting random fail-safes more often than not. Rock is also quite hard... likely a very unpleasant experience for a failsafe'd drone.</p>

CC BY-SA 4.0
2020-04-18T14:25:06.243Z
2020-04-18T14:25:06.243Z
Paul Fernihough
<p>From what I know of the activity, it involves lots of squeezing yourself and your gear through small passages and there's often some water involved. Also, I would imagine, you wouldn't want to risk flying into walls (or people). So, if you need just a tool for exploring the walls and indentations of larger caverns, the best drone would be very compact in transportation, waterproof, stable and have a collision-avoidance system. A controllable camera gimbal is a big bonus for looking in different directions while hovering in place. That feature set suggests something in the Mavic line of DJI drones since they have all of it. They are compact, foldable, rugged, waterproof, stabilized, gimbal-equipped and collision-avoiding. If you want a recon drone, that would be it.</p>

<p>That said, while DJI drones can be flown indoors (and even have a special "tripod mode" that limits their forward speed), there seem to be some quirks with the position-stabilized modes there. Optical stabilization can fail in darker environments, the drone may wander around erratically for some seconds if it acquires some satellites through a window, for example. If you keep to the attitude mode, however, you should be fine.</p>

<p>All in all, if all you need is a camera platform/reconnaissance drone, get a Mavic (one of the smaller ones probably) and mount some powerful LED lights on it. Also, a good idea may be to get some prop guards with it despite the collision avoidance just to be extra safe. You don't want to lose that many dollars (or cut your buddy with a prop) in a cave.</p>

<p>Now, if you want to <strong>have fun</strong> with the drone, that's another deal entirely.
Large caverns have been flown by freestyle and race pilots on several occasions with great success. Depending on the size of the cavern you expect to fly, you might want anything from a larger (75mm+) brushless micro quad to a 4-5 inch quadcopter for huge spaces. The most universal is probably something like an 85mm whoop. Prop guards are a good idea in any case, ducts are probably not if you're looking for performance. Conformal coating all electronics to protect them from moisture is a must. Still, be prepared for the possibility of losing the drone. Also, acrobatic drones are not very useful for looking over stuff in a hover due to the fixed camera uptilt.</p>

<p>A digital video system is good for rejecting multipath signals in enclosed spaces, but note that all current digital systems are way bulkier than analog ones, so I'd probably go with a good analog transmitter and Rapidfire or similar.</p>

CC BY-SA 4.0
2020-04-16T07:26:39.153Z
2020-04-21T03:56:54.790Z
2020-04-21T03:56:54.790Z
FlashCactus
<p>Here's a link of a company that does cave filming using drones. <a href="https://aerialworx.co.uk/drone-filming-caves/#:%7E:text=Drone%20filming%20in%20caves%20is,on%20the%20Isle%20of%20Staffa" rel="nofollow noreferrer">https://aerialworx.co.uk/drone-filming-caves/#:~:text=Drone%20filming%20in%20caves%20is,on%20the%20Isle%20of%20Staffa</a>.</p>

CC BY-SA 4.0
2024-04-28T08:27:17.140Z
While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes.
sempaiscuba
CC BY-SA 4.0
2024-04-28T04:02:31.493Z
2024-04-28T04:02:31.493Z
Guest
<p>If it were me, there are two different kinds of drones I would want. A tiny whoop and a cinewhoop.</p>

<p>Tinywhoop is a loose definition of a very small drone that's about 3 inches wide with guards/ducts around its props and weighing anywhere from 20-50g. They are very durable and fly in places nothing else could. You can assemble them yourself (very easy) or buy one pre-assembled for around $100. You can add a small, powerful LED that allows some pretty fun exploration in dark and very tiny spaces without the risk of loosing a larger, more expensive piece of equipment. <a href="https://www.youtube.com/watch?v=nga_KgekIsU" rel="nofollow noreferrer">Example video of someone flying in their house with the lights out</a></p>

<p>A cinewhoop is a larger drone, more like 6-7 inches wide and weighing 200-400g, also with ducts. Typically it's called a cinewhoop because it's about the smallest thing you would want to fly that can comfortably carry a GoPro. You could equip this with a much more powerful light and have a real blast flying around. Like <a href="https://drones.stackexchange.com/a/138/10">tavis mentioned</a> the DJI FPV system would be an excellent setup for caves as it has great video quality and is very resistant to signal multipathing which is a very common affliction of analog video systems like what you would install on a tiny whoop. Multipathing is likely to be a very real issue inside a cave. If you could live with the analog break up though there are few 'starlight' type analog cameras that can operate in very dark environments. However, I don't think that would be nearly as enjoyable or as useful as a 1000+ lumen flashlight strapped to a DJI equipped cinewhoop. That would be awesome. <a href="https://www.youtube.com/watch?v=xkTwxIUtWbY" rel="nofollow noreferrer">Video here of DRL pilot NURK doing a better job of explaining what a cinewhoop is</a>.</p>

<p>I would say your typical DJI consumer drone would not be well suited to a dark cave. Without GPS they would rely on downward-firing cameras for position hold which doesn't work in the dark. You could possibly rig up light to assist the cameras but I would guess that it still wouldn't work very well.</p>

CC BY-SA 4.0
2021-03-14T02:20:20.893Z
I thought the DJI downward sensors were sonar and camera?
cliffclof
CC BY-SA 4.0
2020-04-16T06:51:05.037Z
DJI-like drones _do_ have collision sensors, though, which would be tremendously useful in an enclosed space. However I don't know whether DJI drones would refuse to fly in such a space without a GPS fix.
FlashCactus
CC BY-SA 4.0
2020-04-16T21:01:00.013Z
@FlashCactus As far as I know the collision sensors are all cameras though. Unless there is something fancy in newer DJI stuff they still need light. You could still add lights to help those cameras but it would just be even harder to equip because now they are pointing in pretty much every direction instead of only pointing down.
ipaq3115
CC BY-SA 4.0
2020-04-15T17:50:17.137Z
2020-04-21T03:56:10.013Z
2020-04-21T03:56:10.013Z
ipaq3115
<p>I do a lot of <a href="https://en.m.wikipedia.org/wiki/Caving" rel="noreferrer">spelunking</a> and I would like to know if anyone has some recommendation as to what type of drone would be the most useful in cave exploration with light and camera possibilities in total darkness.</p>

<p>I am only interested in drone usage where the cave chambers are quite spacious and not for usage in narrow passageways.</p>

CC BY-SA 4.0
2021-03-14T02:21:56.133Z
@KenGraham, Can you link us to some updates if you try anything out with this?  I'm curious how the dust works in a cave system and the whole process.  Cool.
cliffclof
CC BY-SA 4.0
2020-04-15T01:58:49.370Z
Generally closed spaces, low-light and close proximity to humans don't go together with drone usage. Not until flight software becomes far more mature and reliable.
ifconfig
CC BY-SA 4.0
2020-04-15T02:09:12.130Z
@ifconfig Some caves that I have been in you could seemingly fit a cathedral in it.
Ken Graham
CC BY-SA 4.0
2020-04-15T13:48:53.310Z
What kind of problem is the drone supposed to solve? Honest question since I don't know anything about spelunking. If its "looking into hard to reach passages" then maybe a extendable pole with a strong light and a small camera (maybe a FPV camera + goggles) are a more robust solution.
0x6d64
CC BY-SA 4.0
2020-04-15T23:29:19.050Z
@0x6d64 Looking for the possibility of an opening at higher elevations, over a ledge, thus avoiding climbing to find out. Just one possible usage.
Ken Graham
<recommendations><accessories>
Drones for spelunking?
Ken Graham
# Drones for spelunking?

(Asked by: username_0 on 2020-04-15)

I do a lot of [spelunking](https://en.m.wikipedia.org/wiki/Caving) and I would like to know if anyone has some recommendation as to what type of drone would be the most useful in cave exploration with light and camera possibilities in total darkness.

I am only interested in drone usage where the cave chambers are quite spacious and not for usage in narrow passageways.

**Tags:** recommendations, accessories

> **Comments:**
> **username_2**: Generally closed spaces, low-light and close proximity to humans don't go together with drone usage. Not until flight software becomes far more mature and reliable.  
> **username_0**: @username_2 Some caves that I have been in you could seemingly fit a cathedral in it.  
> **username_3**: What kind of problem is the drone supposed to solve? Honest question since I don't know anything about spelunking. If its "looking into hard to reach passages" then maybe a extendable pole with a strong light and a small camera (maybe a FPV camera + goggles) are a more robust solution.  
> **username_0**: @username_3 Looking for the possibility of an opening at higher elevations, over a ledge, thus avoiding climbing to find out. Just one possible usage.  
> **username_1**: @username_0, Can you link us to some updates if you try anything out with this?  I'm curious how the dust works in a cave system and the whole process.  Cool.  

---

## 5 answers

### Answer by username_10 on 2020-04-15. Score: 8 | Accepted answer

If it were me, there are two different kinds of drones I would want. A tiny whoop and a cinewhoop.

Tinywhoop is a loose definition of a very small drone that's about 3 inches wide with guards/ducts around its props and weighing anywhere from 20-50g. They are very durable and fly in places nothing else could. You can assemble them yourself (very easy) or buy one pre-assembled for around $100. You can add a small, powerful LED that allows some pretty fun exploration in dark and very tiny spaces without the risk of loosing a larger, more expensive piece of equipment. [Example video of someone flying in their house with the lights out](https://www.youtube.com/watch?v=nga_KgekIsU)

A cinewhoop is a larger drone, more like 6-7 inches wide and weighing 200-400g, also with ducts. Typically it's called a cinewhoop because it's about the smallest thing you would want to fly that can comfortably carry a GoPro. You could equip this with a much more powerful light and have a real blast flying around. Like [username_4 mentioned](https://drones.stackexchange.com/a/138/10) the DJI FPV system would be an excellent setup for caves as it has great video quality and is very resistant to signal multipathing which is a very common affliction of analog video systems like what you would install on a tiny whoop. Multipathing is likely to be a very real issue inside a cave. If you could live with the analog break up though there are few 'starlight' type analog cameras that can operate in very dark environments. However, I don't think that would be nearly as enjoyable or as useful as a 1000+ lumen flashlight strapped to a DJI equipped cinewhoop. That would be awesome. [Video here of DRL pilot NURK doing a better job of explaining what a cinewhoop is](https://www.youtube.com/watch?v=xkTwxIUtWbY).

I would say your typical DJI consumer drone would not be well suited to a dark cave. Without GPS they would rely on downward-firing cameras for position hold which doesn't work in the dark. You could possibly rig up light to assist the cameras but I would guess that it still wouldn't work very well.

> **Comments:**
> **username_6**: DJI-like drones _do_ have collision sensors, though, which would be tremendously useful in an enclosed space. However I don't know whether DJI drones would refuse to fly in such a space without a GPS fix.  
> **username_10**: @username_6 As far as I know the collision sensors are all cameras though. Unless there is something fancy in newer DJI stuff they still need light. You could still add lights to help those cameras but it would just be even harder to equip because now they are pointing in pretty much every direction instead of only pointing down.  
> **username_1**: I thought the DJI downward sensors were sonar and camera?  

---

### Answer by username_4 on 2020-04-15. Score: 3

I would think one of the stable platforms with obstacle avoidance would work. DJI's newest drones have this feature although you would need to mount a very bright light on the drone for it to be useful in a dark cave. If you're a skilled pilot then I would recommend a very powerful mid-range platform and fit a very bright LED lamp for illumination. The DJI digital FPV system would also be essential to have if you're exploring a cave and examining the walls.

> **Comments:**
> **username_5**: Does the DJI flight software even work in situations where neither the GPS nor the cameras are available?  
> **username_4**: @username_5  You are probably correct that the DJI drone would probably not want to fly without having a gps signal.  
> **username_6**: The DJI digital system (or, rather, its goggles) is rather bulky, though, and that's a major drawback in caves where you must oftentimes squeeze yourself through very tight passages.  

---

### Answer by username_7 on 2020-04-18. Score: 1

Flying in this sort of environment needs to be ***very*** carefully planned + controlled.

The radio frequencies typically used for drone control + video transmission are extremely poor at penetrating any thickness of rock.

Unless you're always able to keep to a very clear line of sight, I think you would be getting random fail-safes more often than not. Rock is also quite hard... likely a very unpleasant experience for a failsafe'd drone.


---

### Answer by username_6 on 2020-04-16. Score: 1

From what I know of the activity, it involves lots of squeezing yourself and your gear through small passages and there's often some water involved. Also, I would imagine, you wouldn't want to risk flying into walls (or people). So, if you need just a tool for exploring the walls and indentations of larger caverns, the best drone would be very compact in transportation, waterproof, stable and have a collision-avoidance system. A controllable camera gimbal is a big bonus for looking in different directions while hovering in place. That feature set suggests something in the Mavic line of DJI drones since they have all of it. They are compact, foldable, rugged, waterproof, stabilized, gimbal-equipped and collision-avoiding. If you want a recon drone, that would be it.

That said, while DJI drones can be flown indoors (and even have a special "tripod mode" that limits their forward speed), there seem to be some quirks with the position-stabilized modes there. Optical stabilization can fail in darker environments, the drone may wander around erratically for some seconds if it acquires some satellites through a window, for example. If you keep to the attitude mode, however, you should be fine.

All in all, if all you need is a camera platform/reconnaissance drone, get a Mavic (one of the smaller ones probably) and mount some powerful LED lights on it. Also, a good idea may be to get some prop guards with it despite the collision avoidance just to be extra safe. You don't want to lose that many dollars (or cut your buddy with a prop) in a cave.

Now, if you want to **have fun** with the drone, that's another deal entirely.
Large caverns have been flown by freestyle and race pilots on several occasions with great success. Depending on the size of the cavern you expect to fly, you might want anything from a larger (75mm+) brushless micro quad to a 4-5 inch quadcopter for huge spaces. The most universal is probably something like an 85mm whoop. Prop guards are a good idea in any case, ducts are probably not if you're looking for performance. Conformal coating all electronics to protect them from moisture is a must. Still, be prepared for the possibility of losing the drone. Also, acrobatic drones are not very useful for looking over stuff in a hover due to the fixed camera uptilt.

A digital video system is good for rejecting multipath signals in enclosed spaces, but note that all current digital systems are way bulkier than analog ones, so I'd probably go with a good analog transmitter and Rapidfire or similar.


---

### Answer by username_8 on 2024-04-28. Score: 0

Here's a link of a company that does cave filming using drones. [https://aerialworx.co.uk/drone-filming-caves/#:~:text=Drone%20filming%20in%20caves%20is,on%20the%20Isle%20of%20Staffa](https://aerialworx.co.uk/drone-filming-caves/#:%7E:text=Drone%20filming%20in%20caves%20is,on%20the%20Isle%20of%20Staffa).

> **Comments:**
> **username_9**: While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes.  

---

