Rocket Recovery via Drone? Rocket-Drone!

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HyperSpeed

Well-Known Member
I have had this idea for months, and I cannot resist any longer from discussing it here.

When I imagine a rocket that helps itself in the recovery stage quite well, I imagine a rocket-drone. My idea of a rocket-drone would use an air frame with 4 recessed areas designed radially around the body tube, where 4 carbon tubes + blades + motors would fold into and clear (for aerodynamics). At apogee it would still deploy a drogue or chute, but the second recovery stage is where it would get interesting. The 4 rotor arms would deploy and flip out, the apogee chute would detach, and the motors would crank up to speed to bring everything to a hover. Just like a 'return to home' on any drone, the rocket would GPS its way back to the launch area, hovering with the forward end now aiming at the ground. Because the rocket will be setting itself down so easily, there would likely be little evidence that the flight even occurred (assuming all went well structurally during flight).

Well, what do you guys think about that sort of idea? Would that be possible to actually build and launch legally? This type of thing would allow a club with a 100x100' launch area to fly L3 beyond 10K feet altitude while surrounded by lakes and heavy forest, but not have to worry about recovery. I don't know that I would actually have a chute that detaches, but I was trying to keep the idea of a chute somewhere in the picture since I know how much you guys would cringe with no chute on-board.

I've lost some of my favorite builds to tracking and wind, and had I had a rocket-drone each time I might not have to miss them! :wink:

dr wogz

Fly caster
What if one rotor doesn't deploy? or not work correctly? What about 2? Is there a safety back-up? What kind of weights are we talking about? I see a drone that's needed to carry a 4lb rocket somewhat large-ish.. Definitely added complexity.. (and L3 rockets can be over 50lbs..)

I think field size is determined by motor size, and these rules are somewhat rigid..

Now, having a drone to search for & recover your rocket is a neat idea.. But personally, I like the walk to find & retrieve my rockets.. gives the sport that added 'physical exertion'..

ttabbal

Well-Known Member
If you are really familiar with multicopters, you might be able to pull it off. Note that you need some rather powerful motors for the larger rockets. As this would be more about control than speed/acrobatics, I recommend low Kv motors and long low pitch props. I wouldn't go quad, I'd go octo. You can lose a couple motors/props with an octo and the control board can still stabilize the craft. If you lose one prop on a quad, it's coming down, hard. I would also consider a secondary emergency parachute. If you detect high speed falling in the flight computer, deploy the chute and shut down the motors.

As I see it, you have a couple problems that need solving.

1) The ability have the arms/motors/props fold up for launch, lock into place for launch and handle the G forces, lock on deploy and be strong enough to hold the whole rocket up.

2) Not tangle in the harness.

3) Power for the whole thing, but not be very heavy. If you're ok with power/weight ratio taking a hit for the rocket part of the flight, it's less of an issue. But this isn't going to be a lightweight contraption. The motors alone will add up.

I'm sure there are plenty more, there always are with this many moving parts. Just a few things to think about while considering designs. My first thought is to build it onto a centering ring structure, and have the body tube cut up to contain the copter parts. If you put the hinge toward the nose, then fold the arms down toward the motor, that would provide some protection from the thrust, and the forces during the rocket burn would help hold it closed. The props would be aligned with the arms for the rocket phase of the flight, allowing the whole thing to fit into the body tube. Design the drogue to keep everything else up and away from the booster section. Deployment would open up like an umbrella, lock the arms in, then spin up the props. You would probably want to have the controller set up to go a ways to the side when it first powers up, so you end up dragging the whole rocket sideways for a while. This is to avoid tangling the drogue, harness, etc. into the octo, giving time for the other parts to fall under the new source of lift.

Another option is to have the arms fixed in the deployed position and use them sort of like fins for the boost phase. You could even mount fins to the arms, using them as gussets. If you use folding glider props, you can keep the props from trying to spin during boost. Set it up so the multi's thrust is "down" compared to the rocket. At apogee, spin up, flip over, now you're an octo.... with a long landing gear... The nose cone could be held with shear pins with a chute in the BT like normal, for emergencies. If you detect a problem on the flight controller, shut down and pop the chute. Or even use a switch on your R/C transmitter.

Blackleaf99

You can choose your behavior, not your emotions.
From the title of this thread, I thought you meant a drone that autonomously flies out to pick up and retrieve your rocket. Nice idea if it could work.

ksaves2

Folks have used them to hunt rockets and have had some successes. It's conceivable one could use a Gawd awfully pricey drone to fly to a GPS position they glean from their tracker, have the drone look around and take command to
hook the harness and carry it back. Problem is: Big rocket = Even bigger drone required.

Also some sites outlaw R/C flights including drones during active launches. After a launch is over it's not a problem.

You fat A's need the exercise anyways so go walk out there to get it! Kurt

RCLoversan

Member
I have had this idea for months, and I cannot resist any longer from discussing it here.

When I imagine a rocket that helps itself in the recovery stage quite well, I imagine a rocket-drone. My idea of a rocket-drone would use an air frame with 4 recessed areas designed radially around the body tube, where 4 carbon tubes + blades + motors would fold into and clear (for aerodynamics). At apogee it would still deploy a drogue or chute, but the second recovery stage is where it would get interesting. The 4 rotor arms would deploy and flip out, the apogee chute would detach, and the motors would crank up to speed to bring everything to a hover. Just like a 'return to home' on any drone, the rocket would GPS its way back to the launch area, hovering with the forward end now aiming at the ground. Because the rocket will be setting itself down so easily, there would likely be little evidence that the flight even occurred (assuming all went well structurally during flight).

Well, what do you guys think about that sort of idea? Would that be possible to actually build and launch legally? This type of thing would allow a club with a 100x100' launch area to fly L3 beyond 10K feet altitude while surrounded by lakes and heavy forest, but not have to worry about recovery. I don't know that I would actually have a chute that detaches, but I was trying to keep the idea of a chute somewhere in the picture since I know how much you guys would cringe with no chute on-board.

I've lost some of my favorite builds to tracking and wind, and had I had a rocket-drone each time I might not have to miss them!
I've had this idea in mind for years. One day I've drawn a sketch and I kept in my wallet for... a while.
Finally I've built a rough prototype.
https://makezine.com/2018/03/21/drone-rocket-hybrid-lands-vertically/
It has been the most challenging thing I've ever built.
P.S.
If you use propulsive landing you don't need to deploy the parachute, but if you want to that for safety reasons, I've already prepared a module for it, which is remote controlled.
https://youtu.be/1WNQxj7vTnM

Well-Known Member
I have been thinking about a drone with a cutting wheel on it that could cut the shock cords of rockets that are hung up on a power line. Easy and safe way to get them back.
Steve

RCLoversan

Member
I have been thinking about a drone with a cutting wheel on it that could cut the shock cords of rockets that are hung up on a power line. Easy and safe way to get them back.
Steve
I believe this not what this post was about.

RCLoversan

Member
What if one rotor doesn't deploy? or not work correctly? What about 2? Is there a safety back-up? What kind of weights are we talking about? I see a drone that's needed to carry a 4lb rocket somewhat large-ish.. Definitely added complexity.. (and L3 rockets can be over 50lbs..)

I think field size is determined by motor size, and these rules are somewhat rigid..

Now, having a drone to search for & recover your rocket is a neat idea.. But personally, I like the walk to find & retrieve my rockets.. gives the sport that added 'physical exertion'..
Generally speaking in rocketry I really like modular structures, therefore you just need to add a RC parachute module, to the cylinder used for the pyro rocket (because you can't use the ejection charge). If you'd like to have an example, watch my test bed using the same AUW of my Rocket Drone (Estes D-12 motor). I've basically used the same rc controlled parachute module of my water rockets, with excellent results.
https://youtu.be/1WNQxj7vTnM

georgegassaway

I have been thinking about a drone with a cutting wheel on it that could cut the shock cords of rockets that are hung up on a power line. Easy and safe way to get them back.
Steve
Uh, H*** no! NOT SAFE AT ALL!

Intentionally flying an R/C (or any model) model NEAR a power line is an incredibly DANGEROUS and STUPID thing.

Just no.

Never mind the other danger of a R/C model with a cutting wheel on it, regardless of power line. Accidents happen, and having a model "Armed" with a cutting wheel of death on it, BAD idea. Hey, why not glue Ginsu knives to the tips of the fins of a 4-finned rocket, and add one to the nose cone too, what could go wrong there?

The one practical method that had involved multicopters helping to retrieve models (mostly model planes and other multicppters) has involves a line with a hook on it, or even just a line. Sometimes, a direct rescue such as the hook grabbing a model from a roof or small island. Other times, delivering a hook with a line, or just lying a line, across a tree limb, so that then the limb can be yanked on by humans pulling on the line.

Sometimes it backfires, trying to use a hook or laying a line, the "rescue" multicopter gets entangled in the tree too.

Here's a successful one that laid lines across the tree, no hooks.

This one almost backfired. The "Rescue Drone" got tangled up in the tree also and briefly was stuck in the tree too. Later they used the drone to deliver a hook with line, in a manner that allowed the drone to separate from the line, so once the hook was set they yanked on the limb until the first model fell out.

mikec

Well-Known Member
having a model "Armed" with a cutting wheel of death on it, BAD idea.
I'm not saying this is a good or safe idea, but multicopter props are likely way more dangerous than a tool that could credibly cut a piece of tubular nylon.

Brainlord Mesomorph

Well-Known Member
My long term goal is RC glider recovery.

/I've seen Youtubes its been done
//but that was a plane w/ a rocket engine
///I want a rocket w/ RC control.

LithosphereRocketry

Pining for the Fjords
My long term goal is RC glider recovery.

/I've seen Youtubes its been done
//but that was a plane w/ a rocket engine
///I want a rocket w/ RC control.
DynaSoar Rocketry (burkefj on the forum) makes RC rocket glider kits. I haven't tried one myself but I've heard nothing but good things about them.
https://dynasoarrocketry.com/

georgegassaway

From the group at Flite Test, the ultimate Range Box that can come to you when you need it... (batteries not included)

(*&^%$#@! I didn't want to buy it! I wanted to invent it! Which actually I will claim; I invented it in 1978. I just didn't perfect it. (*&^%$#@)