Student Rocket Project

[JerryBaumchen 1,075]

Hi folks,

Back in September, a local DZO invited me to come out to a boogie that they were having. So I went. While there I met a couple of Mech Engr students from Oregon State University (OSU). Since I'm a retired ME, I got to chatting with them & I wished them well with their studies.

In October I got a phone call from one of them. He said that he was part of a team working on a student rocket project that they hoped to enter into an international competition in June 2016. Another student and he wanted to come up and see what I might be able to do, in the way of rigging, to help with their project. The project team is about 15 people and these two, along with a few others, are working on canopy recovery of the rocket.

So the two of them came up & we talked about what they wanted/needed and what I might be able to do for them. We talked about making a ram-air canopy for the recovery of the rocket. As I quizzed them, we decided that a 10 sq ft canopy would do the job. I explained what would be a canopy building project and about what I would expect it to take. I gave them an extra square reserve that I had and told them to take measurements for scaling this canopy.

A few weeks later they returned and they had a 10 sq ft canopy. They had done their homework and contacted a number of mfrs. This resulted in AirTec supplying a bunch of CYPRES cutters and Aerodyne built them a canopy ( it is the one you will see in the video ) & a free bag and two small pilot chutes. I did some sewing for them & sent them on their way.

Another few weeks later they called and said that they had broken a line on the canopy & could I fix it. So I drove down to OSU, looked over their project room, met some other team members, talked to them about deployment altitudes, cutter mounting, loop location within the rocket housing, etc. They had been dropping the canopy from the top of the OSU football stadium to check deployments and had broken a steering line. The line is an extremely small line; since I did not have any of this line, I changed out the entire lower steering lines on both sides with CYPRES loop material. It took a couple of tries, but I got everything dimensionally right on the 2nd effort.

A few weeks later they did a deployment test out at the Pacific Northwest Skydiving Center. The first attempt was not fully successful in that the circuit board that was to fire the two cutters on the payload had turned itself off just after loading into the plane. However, we did find that the payload would fall somewhat stable in pilot chute fall ( a smaller version of a tandem in drogue-fall ). The two pilot chutes that Aerodyne had provided were a 12" diameter one and a 10" diameter one. We went with the 12" one.

One of the next tests was a steering control test. This is the one that you will see in the video. The white wheels that you see are the spools that wind up & back to control the canopy. One problem that we had to solve was that there is no person to release the brakes once the canopy deploys. A lot of brainstorming resulted in trying a deployment without brakes; and it worked perfectly.

One thing you will see in the video is that the jumper ( Connor Kelsay ) is holding a pink device in his hand. That is a 'wrap' that I made for him to hold onto the payload, during his deployment, until he releases his grip then the 'wrap' opens up and away goes the payload.

My biggest problem in this project is not taking over & telling them what to do at each step. I have to keep telling myself that this is a learning project for them, it is not for me. However, I am having the time of my life working with them. For me, it is unbelievably satisfying to be around & working with a bunch of eager, smart, soon-to-be engineers. They are the future, folks.

Anyway, here is one video; I hope you like it: https://vimeo.com/158157565

They have another actual launch test scheduled for later this month at an amateur rocket site located east of Bend, Oregon. I went over for a previous launch test ( some good, some not so good results ) and plan on going over for this next one; it is scheduled for 29 Apr 16.

Jerry Baumchen

[billeisele 122]

good stuff, pass it along

Give one city to the thugs so they can all live together. I vote for Chicago where they have strict gun laws.

[38lightning 0]

My longest running flight-related hobby (8 years, less active the last few years due to college eating up my free time) is high-power rocketry. As you may have seen at the test launches, "large" parachutes in the hobby are pretty much always some kind of round (flat, hemispherical, or semi-toroidal). I've seen a couple of other groups fly rockets with steerable ram-airs, and I always figured the tough part would be getting a ram air deployed successfully, as pyrotechnic deployments from a rocket can sometimes be a little bit chaotic. Looking at their deployment test video, it looks like they're separating the payload section and letting it descend a bit under a drogue then using the CYPRES cutter to deploy the ram-air once things have stabilized. Is that correct?

Nice work by everyone involved! I can't wait to see video of the system in flight (on a rocket, that is).

William "38lightning" Carpenter
High-power rocketeer, aerospace enthusiast, engineer

[JerryBaumchen 1,075]

Hi 38,

Quote

it looks like they're separating the payload section and letting it descend a bit under a drogue then using the CYPRES cutter to deploy the ram-air once things have stabilized. Is that correct?

Yes. The design concept is that directly, at or just after apogee, the nose cone will be seperated ( still attached via lanyard ) and the pilot chute will deploy. It will then fall from 23,000 ft in pilot chute fall until 3,000 ft where the two cutters will release the canopy to deploy out from the payload.

Jerry Baumchen

[BIGUN 1,097]

Awesome, Jerry... passing it forward.

But, then no one would expect anything less from you.

The one thing I don't understand is who is in charge of the brake lines (white mechanical wheel) and what's behind it... a gps sensor that guides it to the LZ or someone on the ground controlling it with an RC box?

Nobody has time to listen; because they're desperately chasing the need of being heard.

[turtlespeed 212]

BIGUN

Awesome, Jerry... passing it forward.

But, then no one would expect anything less from you.

The one thing I don't understand is who is in charge of the brake lines (white mechanical wheel) and what's behind it... a gps sensor that guides it to the LZ or someone on the ground controlling it with an RC box?

And can you get it to flare?

I'm not usually into the whole 3-way thing, but you got me a little excited with that. - Skymama
BTR #1 / OTB^5 Official #2 / Hellfish #408 / VSCR #108/Tortuga/Orfun

[kallend 1,672]

Excellent. Accreditation of engineering programs has required a team design project since 2001 and this looks like a good one.

I had used rocket design on a smaller scale with freshmen classes for a number of years, until my launch site was placed "out of bounds".

...

The only sure way to survive a canopy collision is not to have one.

[JerryBaumchen 1,075]

Hi Keith,

Quote

The one thing I don't understand is who is in charge of the brake lines (white mechanical wheel) and what's behind it... a gps sensor that guides it to the LZ or someone on the ground controlling it with an RC box?

As I understand it, it will use a self-guiding system based upon GPS coordinates. I have met the guy 'in charge' of the guidance system and he is an electronic type of engineering student. Nice guy, but they speak in languages that are beyond me. He is also the guy who designed the control board to detect altitude & fire the cutters; they are not using AirTec circuit boards, just CYPRES cutters.

I talked with my contacts on the team about this, as I was concerned that if they just used the one coordinate, it might just be coming in downwind with lots of forward speed ( from the little that we know, it does look like the 10 sq ft canopy has a lot of speed in full flight ). So I suggested that they use two coordinates, one about 500 ft in the air at a location about 500 ft downwind and a second one which is the very dead center that they want to hit.

They told me that they thought this is a good idea and that they are working on it.

I'm an old-school ME ( Class of '71 ), this whole new world of electronics is way out of my retired pay grade.

Jerry Baumchen

[JerryBaumchen 1,075]

Hi turtle,

Quote

And can you get it to flare?

Right now, that is somewhat of an unknown.

The white spools are 2" in diameter ( ~ 6" circumference ) & it only takes about a 1/4 turn ( 1 1/2" of control line deflection ) to control the canopy. And I do not know the speed of the spools when winding up or winding out.

And you can imagine, this is an R & D project for these students; and of course a great learning project.

When I met with some of the team down at OSU they mentioned that they want to win this competition. While that would be great, I told them that IMO it is the learning that they will do from here to then is the real learning process, not the winning.

Jerry Baumchen

[BIGUN 1,097]

Thanks, Jerry. Pretty cool stuff. And, I hear ya about new cool technology... Most look at me like they've smelled a bad fart when I tell them I'm not on facebook. ; )

Nobody has time to listen; because they're desperately chasing the need of being heard.

[RiggerLee 61]

Wamore has done some small ram air guidance systems. They did some really small ones in about the same range. In the end they wound up with a single spool, single stepping motor. They've tried it a number of ways. some of their motors are geared so they can just set the breaks with the motor. Some times the breaks are set and the motor pulls a light weight line that has an eyelet that loops over a yellow cable on the riser and pulls it out of the loop on a two ring, how we do it. But their smallest as I said uses a single motor. The break line runs from one side, down one full time around the spindle, and back up to the other side. It opens and flys in about 1/4 breaks. To turn the motor turns a bit one way, lets out one side pulls in the other. To fly straight it goes back to center. Simplest light system they've come up with. No real flare.

Cutters are $$$ Some people use a heated wire to cut a loop of micro line to release their drogue. So they have a dowel or some thing wrapped in wire. A loop of micro line loops around it and a loop on the drogue, think slink, wire heats and cuts through the loop. Cheaper.

Sounds really cool. Great project.

Lee

Lee
[email protected]
www.velocitysportswear.com

[theonlyski 3]

RiggerLee

Cutters are $$$ Some people use a heated wire to cut a loop of micro line to release their drogue. So they have a dowel or some thing wrapped in wire. A loop of micro line loops around it and a loop on the drogue, think slink, wire heats and cuts through the loop. Cheaper.

Using a 3-ring like the Strong DH tandems is even cheaper and reusable without having to replace the loops every time. You just need some way to pull the cable.

"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

[JerryBaumchen 1,075]

Hi guys,

Quote

Cutters are $$$

Quote

Using a 3-ring

I do not think there is room; the rocket is only 5" in diameter. Things are very tight in there.

AirTec is donating the cutters.

Jerry Baumchen