Using a Drone to Hang Stuff on Fences Beams and Other High Places

Just another guide that follows my experiments of hanging stuff on high places with a drone.

Drones are a great way to hang stuff they can reach pretty much anything.

I use them to hang pictures and solar-powered LED lights on top of abandoned towers and fences.

You might ask why, but that is the wrong question. The right question is how?

The approach in this guide is using a hook to attach the payload to the top of a fence or to narrow beams or cables. This works when you have a narrow target that can fit in the hook (like a fence/cable or beam). If you want to just stick your payload to a flat wall see previous tutorial:

The full guide is available in this video: https://www.youtube.com/watch?v=eLwvoa-CqTs

I recommend watching it before reading further.

DJI AIR 3 (1000usd, 750-gram payload)

Airdrop attachable remote payload release device(10usd).

1.8-2 mm rigid iron wire for hook.

0.2-0.5 iron wire for hanging the payload.

Flat skewer stick (40cm), + Padding tape + Zip tie.

The approach is simple: choose whatever payload we want to hang (picture/solar light) and attach it to the hook (the hook is simply a rigid bent metal wire).

Next, we hang the payload on a payload dropper device (which allows remote release of the payload). The drone flies above the target. Once the hook grabs to the target and the payload is in place, we use the remote release mechanism to detach the payload from the drone.

The naïve approach is to hang the payload from the drone with a wire directly below the drone. However, this will cause the payload to rotate and swing randomly making it hard to position. Also if the wire goes directly below the drone it can block the drone's downfacing sensors making it behave strangely.

The solution is to attach a horizontal stick to the drone so that the payload can be hung using wires from both sides of the stick. This gives a broad base and two attachment points which make the payload more stable. The stick can be attached to the payload release mechanism using a zip tie. The important part here is that if the stick is too loose it can move and vibrate and even touch the propellers, so you want the zip tie to be very tight. However, if the stick is too tightly bound to the payload release system it can create friction that will not allow it to be released. So there is a narrow balance here. I found that padding the stick with soft padding tape allows it to squeeze into the payload release device without creating too much friction. It's also recommended to check that the stick is stably bound to the release mechanism even under vibration but can also easily be released before actually flying.

For this I used 40 cm skewer stick. Binding the payload to the stick using thin metal wires (0.2-0.5mm). The reason for preferring metal wire is to reduce vibrations and swinging. Wire length of around 1.8-2 meters distance between the drone and payload is good for AIR 3.

It might sound simple to just fly with the hook above the fence and descend until the hook grabs the fence. This however is very hard given the limited precision of the drone and the payload's tendency to swing.

A much easier approach is to make one side of the hook shorter. Then move the drone with payload forward until the payload presses into the target, once the drone reaches and slightly passes the target the payload below the drone will be pressing the target (target means fence/beam/cable). At this stage, it's easy to position the hook by moving the drone up and down.

Unstable payload and hanging. If the payload constantly swinging or isn't sitting in place after hanging:

⦁ Add more weight to the bottom of the payload (like a small rock).

⦁ Use longer or more rigid wires and more distance from the drone to the payload (remember the drone generates lots of downward wind).

⦁ Make sure the stick is tied tightly and does not swing freely.

Payload does fail to detach:

⦁ Make sure that the stick does not bind too tightly to the payload release mechanism and does not prevent or block the payload release mechanism, either mechanically or by friction.

Drone behave strangely:

⦁ One problem I had with DJI AIR 3 is that the drone downward sensors identify the wire and or payload as ground, to avoid this use a long stick make sure that the wire dont got directly below the drone.