Purdue Students Building Moon Lander Rocket

tekgoblin sends words that a team of students at Purdue University are working on a project to build a rocket engine that could be used on a future Moon lander. Quoting: "Graduate students Thomas Feldman and Andrew Rettenmaier are part of a team developing a thrust chamber for NASA's Project Morpheus, which includes research to develop new technologies for future trips to the moon, Mars or asteroids. The rocket must meet stringent design and performance specifications related to factors including efficiency, size and weight limits, thrust and the ability to dynamically throttle the rocket from 1,300-4,200 pounds of thrust, Feldman said. ... A development test chamber has been designed and is ready for testing. This heavily instrumented chamber is far bulkier than the eventual flight chamber, and data from upcoming tests will be used to refine the flight engine's design."

ooh yeah

[tekgoblin]

Boiler UP!

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[sconeu]

So what *DOES* the future of the Turkish textile industry look like?

Re:Such a waste

[wsxyz]

They seem to be learning about intelligently designing a rocket motor, which is obviously unconstitutional, and can't possibly work anyway.
I don't fly want to fly in a rocket designed any other way than by natural selection.

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[tragedy]

Rockets are made through intelligent design and _artificial_ selection. Rocket designs that explode during testing generally don't get to have unmodified offspring.

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[LifesABeach]

Given that the design is from Purdue, not Evansville, one hopes that when metric conversion is discussed, it isn't considered a religious subject,(SNAP! Purdue). But all inner university rivalry's aside; given that the name of the project is, "Morpheus"; I would hope that Purdue's students would anodize the engine red.

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[tragedy]

Given that the project name is Morpheus, I just hope they don't fall asleep while operating rockets.

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[LifesABeach]

I believe that if Purdue anodizes the engine blue, then I would hope that the crew wakes up in time.

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[Roachie]

Yea, once dogs evolve enough to teach aerospace engineering it is my hope that they will be the ones to put and end to crap like this.

Nerd quotient

[currently_awake]

Nothing like building space craft. And the USA has plenty of launch options for stuff that doesn't come back in one piece.

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[gizmo_mathboy]

The Purdue folks just built the engine. They didn't build the lander.

Pfft

[sir_eccles]

It would be easier to just use a solid rocket booster from ATK.

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[gizmo_mathboy]

Because you can vary the thrust on a solid rocket booster, not.

The lander probably needs variable thrust. Solids won't be very useful for that.

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[tragedy]

The GP is, I believe, making a joke about the corrupt political process through which most NASA parts are sourced (by congressmen who know nothing about rocketry) and which often becomes an overriding factor in their design. Basically, congress tells NASA that they will use engines from _this_ manufacturer, in _this_ district, then NASA has to design the rest of the mission around what that manufacturer can actually provide them. ATK bought the Thiokol rocket division (after a few intermediate splits and me

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[tragedy]

I did read the findings of the commission , although it's been a long time. Would "came apart like wet tissue paper" have been more accurate? They were extra-fragile in the Challenger case because they were cold, but even when not cold, they apparently made it a significant fraction of the way towards total failure on many previous uses. I may have misremembered just how severe the previous failures were. Oh, and I certainly know who Richard Feynman was. The fact that the O-rings were already a known proble

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[hackertourist]

The boosters for Ariane 5 (a bit smaller than the Shuttle SRB, but close enough) are shipped to French Guyana empty. ESA/Arianespace have built a casting facility on site.

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[tragedy]

Ah. Can I assume that they are completed in one pour and conclude that completing a large solid rocket booster in one pour is therefore not impossible?

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[hackertourist]

I assumed that they'd be cast in a single pour, but apparently not: booster manufacturing process [esa.int]

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[tragedy]

Hmm, diagram on that page is very unsatisfactory. Hard to tell if they do use interlocking segments with an o-ring in their design or not. If you actually pour in place, I suppose you could probably do away with the o-ring design by just leaving enough clear space that you can weld the inner sections together safely, then pour directly on top of the previously solidified propellant rather than having to do the careful alignment and rely on relatively flimsy o-rings. Maybe it just doesn't matter if hot gases

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[gizmo_mathboy]

Compare the Lunar Lander from Apollo to the Armadillo craft to the Morpheus project.

There is only so many configurations where you have a centrally mounted engine and a bunch of spherical propellant tanks.

Not so much a knock off as that is what physics and mother nature dictates.

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[gizmo_mathboy]

Would you rather deal with 2 systems (variable thrust engine and an air bag deploy system) or just 1 system?

You would need an engine regardless, there is no atmosphere on the moon so you can use the Martian solution. You could use a parachute for the bulk of the descent and then have the air bag.

I wouldn't even dream of using an air bag for manned missions, no control of the impact at all.

With variable thrust you have controls systems to keep things stable and can vector out of the way like Neil did on Apol

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[tragedy]

Square-Cube ratio. Or rather, sphere-radius to sphere volume ratio. Larger payloads are a lot harder to land with an airbag system than small ones like the Mars rovers. As the payload gets more massive, the size (and complexity) of the airbag you need to safely stop all of its kinetic energy increases more. That's why the up and coming Mars rover, which is the size of a compact car, is not going to be landed with an airbag system.

Hmm. That got me thinking, anyone have the numbers on the maximum speed an obj

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[mmontour]

Hmm. That got me thinking, anyone have the numbers on the maximum speed an object can reach falling towards the moon?

Same as the escape velocity, which Google says is 2.38 km/s.

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[tragedy]

Definitely pretty ouchy. I was just asking because of the whole airbag question. With no aerobraking, you have to have rocket boosters to land, or you have to have a passive landing system that can absorb a ridiculous amount. Just wasn't sure offhand what the best case scenario was for that ridiculous amount.

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[Coren22]

Woosh?

What's wrong with the Lunar Module descent engine?

[jwilso91]

TRW's lunar module descent engine was quite a piece of engineering. Turns out that the ability to throttle down to 10% of rated thrust is rather difficult to achieve in a biprop engine. The eventual design made some serious compromises to gain the throttleability that generations have enjoyed in lunar landing simulators - it could not run stably at all in the 65%-95% range.

I can understand wanting to reinvent the wheel for the sake of the inventing, but this was a particularly tough nut to crack and one (to