Author Topic: CEV RCS and Solar Panel Canfield joint proposal (Read 53276 times)

AndyMc · « **Reply #20 on:** 01/06/2006 11:20 pm »

First thoughts: Interesting, Complex - more moving parts than standard thrusters. It seems to be a solution looking for a problem - which I don't think exists in this case. It also introduces some problems of its own, most already mentioned by others in this thread. However this type of mechanism, beefed up, could offer an alternative to gimbaling existing engines such as the RL10, giving a greater range of movement for vectored thrust. I'm thinking of its possible use in landers such as the LUNOX study of 1993: http://www.abo.fi/~mlindroo/Station/Slides/sld051p.htm

Though they wouldnt really fit in with the particular landers in this study, they could offer a greater range of engine gimbal to this type of spacecraft, saving having to nose down to acheive orbit. Something akin to the harrier jump-jet transitioning from vertical to horizontal flight. They would enable ascent, retro-burns, and plane changes without having to re-orientate the spacecraft. Whether this is a useful feature is open to question. But it would allow pilots to see the landing site earlier through the forward windows, without having to use tv monitors.

A very clever mechanism. I just worry if those hoses and cables could take the repeated flexing if used as shown in the video.

Tony T. Harris · « **Reply #21 on:** 01/06/2006 11:24 pm »

I don't think the flexing is a problem. Using the right pipe/hose with proven tested ability, and I'm sure it's moved on since my day, it wouldn't be a problem.

Bruce H · « **Reply #22 on:** 01/06/2006 11:26 pm »

Very clever system and I agree with Andy, I believe this will be for missions not to the ISS, but for Lunar missions. Extra and more dynamic corrections, very useful. More details will be very welcome, I look forward to reading them.

Firestarter · « **Reply #23 on:** 01/06/2006 11:34 pm »

Very nice, lets get this baby on the road and go exploring. Apollo on Steriods this aint, this is similar shape, big time advance. Boo Yaa!

AndyMc · « **Reply #24 on:** 01/06/2006 11:41 pm »

Just had another thought. This type of thruster would be very useful for station keeping - say on a space-station at L1, L2 etc.

Launch Fan · « **Reply #25 on:** 01/06/2006 11:47 pm »

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AndyMc - 6/1/2006 6:41 PM

Just had another thought. This type of thruster would be very useful for station keeping - say on a space-station at L1, L2 etc.

Good call. Possibles with automated cargo, etc. etc. Wonder how much this costs too.

HarryM · « **Reply #26 on:** 01/06/2006 11:54 pm »

It certainly offers more flexibility figuratively and literally, and not just for the thrusters and panels. I think it is more critical actually to the solar arrays as there is no easy way around that problem when in BBQ mode. You can angle the vehicle so it is not perpendicular to the suns rays, but then your solar arrays will likewise only get about 30-40% sunlight.

Which begs the question, what is the overall minimum solar array exposure needed to keep the craft functional? In a low lunar orbit it will be in shadow ~ 50% of the time. Most of that will be in dormant mode while the crew is on the surface, but would not be good to "have" to leave the CEV if it in a low orbit (Earth included) because it is not getting enough juice from the arrays over a set amount of time.

Shuttle Man · « **Reply #27 on:** 01/07/2006 12:02 am »

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HarryM - 6/1/2006 6:54 PM

Which begs the question, what is the overall minimum solar array exposure needed to keep the craft functional? In a low lunar orbit it will be in shadow ~ 50% of the time. Most of that will be in dormant mode while the crew is on the surface, but would not be good to "have" to leave the CEV if it in a low orbit (Earth included) because it is not getting enough juice from the arrays over a set amount of time.

Allow me to make a phone call and get you those figures. I know just the man.

James Lowe1 · « **Reply #28 on:** 01/07/2006 12:13 am »

Worth pointing out to the new people here lately that the CEV particular thread has a huge amount of info and images during the process so far.
http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=493&start=1

NASA_LaRC_SP · « **Reply #29 on:** 01/07/2006 12:18 am »

If Dr. Steve Canfield is reading this thread, congratulations on a great concept. Some mathematics involved it this joint, very clever.

BSAE · « **Reply #30 on:** 01/07/2006 12:24 am »

Can anyone speculate as to how much weight could be saved with this system? Or will it end up weighing about the same as quad thrusters?

To The Stars · « **Reply #31 on:** 01/07/2006 12:33 am »

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BSAE - 6/1/2006 7:24 PM

Can anyone speculate as to how much weight could be saved with this system? Or will it end up weighing about the same as quad thrusters?

It's a weight saving, I'm assuming from appearance. It would help if we knew what alloy the joints are made of.

NASA_Twix_JSC · « **Reply #32 on:** 01/07/2006 12:40 am »

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AndyMc - 6/1/2006 6:41 PM

Just had another thought. This type of thruster would be very useful for station keeping - say on a space-station at L1, L2 etc.

This is a perfect simplification of any spacecraft that is stablized along three axis. Someone's going to get rich off this design.

Avron · « **Reply #33 on:** 01/07/2006 12:42 am »

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To The Stars - 6/1/2006 8:33 PM

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BSAE - 6/1/2006 7:24 PM

Can anyone speculate as to how much weight could be saved with this system? Or will it end up weighing about the same as quad thrusters?

It's a weight saving, I'm assuming from appearance. It would help if we knew what alloy the joints are made of.

Some one should do some FMECA on these puppies... looks like a lot of failure modes.... again we may be getting the old story of mass saving, but greatly increasing the risk factors... like my favourite foam issue.. it could be covered, but there is a mass penalty..

I must say I like the joint design.. if it was redundant I may be a lot less worried.

newsartist · « **Reply #34 on:** 01/07/2006 12:47 am »

A general comment; not in rebuttal to anybody here.

What happens in a failure mode? Losing one, is there a greater percentage of control loss, with fewer options to work around it?

GirlygirlShuttlefan · « **Reply #35 on:** 01/07/2006 12:53 am »

So what did they do with the Apollo when one of the four on a block failed?

Rob in KC · « **Reply #36 on:** 01/07/2006 01:34 am »

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NASA_Twix_JSC - 6/1/2006 7:40 PM

Quote
AndyMc - 6/1/2006 6:41 PM

Just had another thought. This type of thruster would be very useful for station keeping - say on a space-station at L1, L2 etc.

This is a perfect simplification of any spacecraft that is stablized along three axis. Someone's going to get rich off this design.

True and that'd reduce costs, making it even more viable.

SRBseparama · « **Reply #37 on:** 01/07/2006 02:39 am »

Nice video, the CEV looks a lot better than the orignal images Griffin put out in his VSE address.

Stowbridge · « **Reply #38 on:** 01/07/2006 03:09 am »

Interesting, very interesting. Passing this information around.

Polecat · « **Reply #39 on:** 01/07/2006 03:38 am »

I'm aware of the fact this thread is a very good basis for questions that needs to be asked about this interesting concept, but could I reccomend a specific question thread, should the opportunity arise and be secured for asking the persons involved some questions. I'm *sure* there are even Exploration Systems and Engineering people or interested thereof, who are for some reason not fully briefed and would it welcome the opportunity to find out finer details of this concept, even if as background before they may wish to present it. It would be benificial for both parties involved. Thank you.