I was lucky enough yesterday to have a chance for an up-close and personal visit with Morpheus. Morpheus grew out of the efforts of Project M and stands with its own list of accomplishments. The Morpheus testbed, done in cooperation with Armadillo Aerospace, is providing an avenue through which the development of future landers, to the Moon or beyond, is done better, in less time, and with less money.
Since its beginning, the Morpheus team has focused on off-the-shelf solutions, modularity of components, rapid turn-around of testing, testing as much as possible, and making use of the talents of other NASA centers. But more than the hardware or software innovations that are a hallmark of Morpheus, one of the project’s biggest hallmarks may very well be its affect on those working on it. Gone are the days, as one engineer put it, “…when you have a file cabinet for every screw”, a natural outgrowth of the Shuttle era.
It has to be remembered that during the 30 years that was the Shuttle era, making any changes to the spacecraft required a great deal of analysis and paperwork. Rather than test and test again, the workflow was one of analyze and analyze again. When one is talking about changing a crewed spacecraft that works, such mindset is perfectly understandable. After all, getting the crew back safely was, and remains, Job #1. Anything affecting the spacecraft must be well understood before a change is made. Since Shuttle was the biggest program at NASA for these last 30 years, its careful, conservative mindset spread throughout the Agency. Unfortunately, such a working mindset can suffocate and stifle initiative that is crucial in developing new technology programs.
The ruling philosophy at Morpheus is to test, analyze and test again. And sometimes the solution to testing and analyzing a problem lays not with the complex but with the simple.
Commotion of Motion
Take the issue of fuel sloshing, one that has affected rocket designers since the beginning of liquid rocketry. Morpheus currently has 4 46″ tanks, 2 for liquid methane and 2 for liquid oxygen. The effects on Morpheus’ motion and stability due to fuel sloshing were an unknown. How do you design your guidance and control to handle such movement? What movement are you designing to deal with? Is the problem big enough that the fuel tanks should be designed in a certain way?
One way to solve this puzzle is to grab a Computational Fluid Dynamics (CFD) software package, design, build and run a model as you best understand it, and examine the results. This could cost a good amount of money and time. Another solution is to build a rough replica of the Morpheus frame and tanks from parts bought at Home Depot and test it. This is both quick and inexpensive. Within a week and for under $100, the Morpheus team was able to watch not only the expected side-to-side motion but also an unexpected circular motion caused by interplay of the motion of liquids. From this inexpensive test, the Morpheus team fuel tanks that lessened this motion and a guidance and control capability to steady out the motion.
Managing the Mission Test
The Morpheus team faced a problem early on; how to get the software needed for testing and monitoring Morpheus and do so quickly and without breaking the bank. The prospects were not good that an effective solution was readily available. That is, until one of the Morpheus engineers sent out messages to other NASA centers asking if anyone had a solution. In stepped Goddard Space Flight Research Center.
Goddard has been working on flight software for awhile. Rather than build a custom package for every event, Goddard modularized the software so that those using it could take what they needed and toss the rest. In adopting the Goddard software, the chief task for the Morpheus team went from designing and coding a custom package, or having contractors do that, to one of building the interface between the Goddard software and the Morpheus craft. The end-result is a package that is the closest thing I’ve seen to the G environment that makes National Instruments’ LabView so popular. Don’t like an interface, redesign it in minutes to what works for you. Want the interface to look like the actual craft schematic, no problem, as the picture above shows.
Morpheus Rocket Engine
Morpheus has a methane powered engine. While methane does not have as high efficiency as hydrogen, that is its Isp is about 20 1/s lower, it makes up for that in other ways. Methane is easier to handle, store, and requires less complex and costly equipment. One of the innovations of the Morpheus program is that their engine uses a sheet of liquid methane to cool the engine nozzle. This has the effect of regenerative cooling, which is used on the current Shuttle engines, but without the complex plumbing. So, while there is a performance penalty in lost fuel, performance is boosted because the engine can run hotter. In the end, the engineers feel like it’s a performance wash. An additional benefit of methane is that it can be created in situ much more easily than can hydrogen.
Currently, the Morpheus team is tuning the engine. In the image below, mid-way down you’ll note what appear to be dark, metal screws just above where the engine’s injector plate would be. The propulsion engineers are using these plugs to tweak the acoustics of the engine.
The Morpheus engine is historically noteworthy; it is the first rocket engine developed by civil servants.
What Does The Future Hold?
Morpheus is to undergo a series of hot-fire tests. This is to build-up confidence in how the vehicle behaves. The big question on the first tests is whether Morpheus can stand on a pillar of fire? Another series of test will demonstrate whether Morpheus can transverse from one test pad to another? And if all goes well, this summer Morpheus will go out to White Sands Missile Range where its performance will be expanded.
But what about the beyond? One of the engineers emphasized that if the team were given the money to got to the Moon, they could accomplish that and quickly. Morpheus is currently sized for a full lunar mission, including the lunar orbit insertion, initial descent, and landing stages.
Regardless of whether Morpheus makes it to the Moon, its real impact has been on the people who have worked on it and the way they work. Morpheus puts to bed the notion populated by some that government in general, and NASA in particular, can do nothing right. The principle of testing and not being afraid to fail harkens back to a time few of us can remember in our nation’s space program. This kernel of change, if it propagates out to the rest of NASA, could push NASA closer to the innovative and responsive agency it once was for pushing the envelope in space exploration. And that is good for our nation.