Sneak Peak: Jolly Logic's Easy Dual Deployment

This is exactly the answer to my problems I have been waiting for. I have gotten away from DD flights mostly because they are not elegant and seem overly complex for the type of flying I enjoy. Your solution is exactly what I have been looking for. Very well done sir. I'm a buyer when HALO hits the market!

BTW, I assume the release is pyro free, is it a magnet?

Jim,

Have you flight tested the configuration in the video? My concern would be the drag forces essentially pulling the chute out of the tether. On the other hand, there are configurations where that wouldn't be an issue (burrito roll). Excellent product and I can't wait to get one.

Kevin

This is a pretty cool design in that it's pyro-free and doesn't require strategic wire routing.

I feel it has the same issues as a cable cutter from a reliability standpoint, but it's certainly an improvement on the design for those that don't otherwise fly an altimeter.

kruland said:

Jim,

Have you flight tested the configuration in the video? My concern would be the drag forces essentially pulling the chute out of the tether. On the other hand, there are configurations where that wouldn't be an issue (burrito roll). Excellent product and I can't wait to get one.

Kevin

Click to expand...

I was thinking the same thing last night. Simply from the standpoint that motor ejection, on average, likely has a higher velocity than baro based ejection. I also see no reason why you can't use a baro for apogee and this for main. I have three rockets right now that already have altimeter bays that I could potentially use this in as an alternative to my cable cutters. Looks very promising, do you have a price point yet?

Very clever, John! I've just about given up on cable cutters, this looks like the perfect solution for DD on those short fat rockets where you can put a deployment-charge altimeter in the NC for the drogue but you don't have an easy way to handle the main. Just reef the main as the drogue, and use the Easy DD to open the main.

I'm not understanding where people are having issues with a cable cutter. I've only had 1 failure and that was user error due to the fact that I forgot to hot glue the igniter into the closure. Other than that I've had 100% success.

John Beans said:

I'd worry about it not sliding out cleanly from a BT-55, which is 33mm. I think folks could make it work, like put most of the chute BELOW it and make sure that at the top it is clearly free and not snug or jammed in the tube, and maybe powder the tube. But that means that you'd need to be super-careful, which doesn't leave much margin for error. I don't know. Maybe?

Click to expand...

Yeah, that's kind of what I was thinking as well. I guess I just need to try it on something a little larger....flying my Semroc SLS Aero Dart on an F15 in that field would be an application I think.....Hmmmmmmmm

OK, John....it's been a day, what's the hold-up? Is is out yet? Is it out yet? Is it out yet? (Grand-rocketeer-inspired post.)

blackbrandt said:

I'm not understanding where people are having issues with a cable cutter. I've only had 1 failure and that was user error due to the fact that I forgot to hot glue the igniter into the closure. Other than that I've had 100% success.

Click to expand...

I kinda agree. My only cable cutter failure was due to the same reason. The Jolly unit is similar to the cable cutter but you don't have to run a wire to a remote altimeter or even need an altimeter bay. I feel this is what rocketry has been waiting on for a long time. I can't wait to get my hands on one and test it with chute bags. This looks to be perfect for the way I fly. So much want!

Congratulations, you have invented the Smart Parachute™.

('bout time SOMEBODY did it, if you ask me)

John Beans said:

Chute Release monitors the ground pressure, then looks for a flight over 100 feet, then waits until the rocket is approaching the set altitude and begins opening in a timely way so that it has released by the appointed altitude.

If you think through all of that, the only thing you'd want to be careful about is that Chute Release has a valid starting reference point for ground, and that you "get the laundry out" somewhere up there.

Hope that makes sense.

Click to expand...

Actually, no. It has to sense apogee, right? Otherwise it is going to deploy on the way up instead of the way down. What did I miss?

The price will be the biggest deal maker/breaker IMO.

Anything more than about $40 and I'll just run a wire out of my altimeter bay and use a cable cutter. Now, if it's less than $40 I may consider it...

John Beans said:

It will sense ejection pressure (like our current altimeters), but it's designed to ignore it. You'll want to protect it just like you protect your chute from direct gases and embers, but it will be fine.

Click to expand...

Interesting, so...is it recording the apogee altitude? And you've programmed it to ignore the over-pressure at the ejection event?

Bat-mite said:

Actually, no. It has to sense apogee, right? Otherwise it is going to deploy on the way up instead of the way down. What did I miss?

Click to expand...

John, we wouldn't want it opening on the way up, that's for sure!

It's got all of that logic in it. I was simplifying. The firmware goes through states like "sitting on the ground" and "boosting" and "falling." So in normal operation, it wants to be above the target altitude, falling, and anticipating when to open.

There are corner cases to deal with. For instance, what do you want to have happen if the flight never reaches target altitude but is coming down? Right now in that case, Chute Release has decided to err on the side of opening. The most likely case is a crazy sideways flight (or someone who forget to change their setting from a previous flight), but in either case Chute Release would err on the side of opening the chute.

blackbrandt said:

The price will be the biggest deal maker/breaker IMO.

Anything more than about $40 and I'll just run a wire out of my altimeter bay and use a cable cutter. Now, if it's less than $40 I may consider it...

Click to expand...

Which cable cutter do you use?

blackbrandt said:

The price will be the biggest deal maker/breaker IMO.

Anything more than about $40 and I'll just run a wire out of my altimeter bay and use a cable cutter. Now, if it's less than $40 I may consider it...

Click to expand...

yeah, but there are many who don't want an altimeter bay. motor eject and this product and you're good to go.

John Beans said:

Which cable cutter do you use?

Click to expand...

A clone of the archetype cutter. Cost a few bucks to make.

RKeller said:

yeah, but there are many who don't want an altimeter bay. motor eject and this product and you're good to go.

Click to expand...

That's me! Price point is a pretty small part of the equation for me. I really want to do high altitude flights, but because I really don't want to fuss with electronics and ground testing, this is a dream come true.

Everyone has their own opinion, and I respect that, but I guess I'm just one of those people who flies an altimeter in EVERYTHING just so I can have data. All of my rockets either have an altimeter bay or are being retrofitted with one.

kruland said:

Jim,

Have you flight tested the configuration in the video? My concern would be the drag forces essentially pulling the chute out of the tether. On the other hand, there are configurations where that wouldn't be an issue (burrito roll). Excellent product and I can't wait to get one.

Kevin

Click to expand...

Agreed. The cable cutter looks fantastic on the ground, but issues occur in flight during ejection and freefall - tangled lines, pulled ematches, burritos that do/don't unfurl, etc. Some of these aerodynamic concerns apply to the HALO as well.

However, the concept is ideal for simple DD- no pyro, no ebays. Hope to see more on this. Please, squeeze it into a 38mm tube!

Buckeye said:

Please, squeeze it into a 38mm tube!

Click to expand...

Yes please.

Buckeye said:

However, the concept is ideal for simple DD- no pyro, no ebays. Hope to see more on this. Please, squeeze it into a 38mm tube!

Click to expand...

patelldp said:

This is a pretty cool design in that it's pyro-free and doesn't require strategic wire routing.

Click to expand...

The most salient points/comments regarding this gizmo ^^^

I'm curious about the release mechanics and MSRP?

A great product and I will have one when available.

I have built and ground tested and have ready to flight test a similar device that is RC based. It is a tiny ply box with a lipo battery, a 3 gram 2.4 Ghz RX and a 5 gram servo that will release a rubber band that is reefing the chute. Anchored by a tether and I have some sandpaper glued to the back of the ply box to prevent the assembly from sliding on the chute bundle during boost or ejection

Allows main chute release on demand when desired.

My ply box is a little thicker than your altimeter based product.

Not for everyone, but I have tons of RC gear and was able to build this one from my spare parts box .

This looks great. Another option for more choices on how to fly - this one being simple and clean. I like it.

That said, if AT ALL possible, it would make a huge difference if it could fit into a 38mm tube. For my type of flying this is pretty much THE airframe size I could see using something like this in most often. Smaller than that I generally either fly low enough to not need "dual deploy" or I'm flying minimum diameter at much higher altitude and I'd be using much more sophisticated avionics, and for larger than that standard dual deploy setups work just fine already. Sure I can see plenty of applications for HALO in larger sizes and would likely use them, but 38mm is where I sort of "need" it.

I'll be watching, and waiting with my checkbook, for when these hit the market,
another great - and unique - product from Jolly Logic!
s6


(postscript: I don't want to derail this thread from it's main purpose/theme, but for all those that have been having trouble with CableCutters, I've found the key is to rig and use a small pilot chute. This has solved all my issues with CCs, and I now use them with confidence and reliability. Search the forum elsewhere for ways to do this.)

Stop bothering the guy he is busy working on Dick Stafford's and my next purchase.

H_Rocket said:

Stop bothering the guy he is busy working on Dick Stafford's and my next purchase.

Click to expand...

+1 +1 +1 (forum doesn't like one +1)

This looks like a fantastic product! I want one I can even see myself modifying my current DD rockets to use this instead (by "modifying" I mean removing the altimeter bay and converting the upper section into a payload bay) . I too am very interested in the cost.

grouch said:

I kinda agree. My only cable cutter failure was due to the same reason. The Jolly unit is similar to the cable cutter but you don't have to run a wire to a remote altimeter or even need an altimeter bay. I feel this is what rocketry has been waiting on for a long time. I can't wait to get my hands on one and test it with chute bags. This looks to be perfect for the way I fly. So much want!

Click to expand...

Ditto. Cable cutters work fine. My failure was my fault. But easier,, simpler, fewer wires is better.

I use homemade cable cutters and just bought my first pair of archetype cable cutters. $40 would be a fair price. Under $40, I'd buy a couple at least

blackbrandt said:

I'm not understanding where people are having issues with a cable cutter. I've only had 1 failure and that was user error due to the fact that I forgot to hot glue the igniter into the closure. Other than that I've had 100% success.

Click to expand...

For me it's more a question of mitigating perceived failures as well as comfort and possibly a preference.

I have several cable cutters, and have also had success with them. I do think it is also a bit premature to make the call...but this new inovation certainly looks promising.

My perceived concerns over the cable cutter have always been what if the ematch wires break. Yes I secure them and coil up some slack, however anything can happen in the air stream. With this technology there are no wires to fail. There is also the potential failure of the e-match. I now test my e-matches for resistance, when I can and remember, but that is not a 100% guarantee. With the "JLED" (Jolly Logic Easy Deployment) I will be watching for the reliability of the servo but it is too early to know how legitimate that concern is, if at all. In one of the original cable cutter how-to videos they bring up the concern of losing BP out the end with the o-ring. I am not sure if this has ever resulted in a failure but it has stuck in the back on my mind (legit or not). I do know from speaking with others, as well as some ground test results and post inspection of my hardware, that there is a legitimate concern with the aluminum piston failing to cut the tie in the cable cutter, due to wear. This is why I use the stainless pistons and I am much more comfortable with that choice.

Actually I have never had a cable cutter fail but I have had my deployments fail using a cable cutter. This was due to experimenting with deployment bags and pilot chutes connected to a cable cutter...a configuration I may try to pick up again with this product.

Again too early to tell and I am sure I am overlooking something when comparing the two technologies, however for me it may simply come down to a comfort level...plus one thing I know that I will not miss, is soaking my hardware post flight to clean the BP residue.