NASA’s Morpheus experimental rocket-powered vertical takeoff and landing testbed is scheduled to resume testing in November after successfully completing a series of free flights earlier this year. Morpheus is one of the agency’s projects to develop technologies enhancing the capabilities and reliability of interplanetary surface exploration missions.
Following successful flight testing with the Morpheus Bravo vehicle, project managers decided to prepare for a second series of three follow-up tests to further improve its systems and capabilities. The first of these is scheduled to begin this week at Kennedy Space Center from a specially constructed simulated lunar landscape north of the Shuttle Landing Facility. Morpheus testing at KSC will conclude with two more powered tests in early to mid-December.
Check Out These 360-Degree Panoramic Views Of Morpheus! |
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 In The SLF Hangar |
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 On the launch pad |
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 On the launch pad |
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 The Landing Field |
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 Inside Launch Control |
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Risk Mitigation
When attempting to send spacecraft to other planets and bodies in the Solar System, engineers say that the most difficult aspect is achieving a successful autonomous landing on unknown terrain. Often, the the distance to mission controllers on Earth is so great there are significant communication delays and it requires the spacecraft to be programmed to guide itself to touch down without human intervention using pre-programmed commands that cannot be updated in real-time. As a result, a lander faces a significant risk of failure if the environment changes in the final stages of entry or if there are previously unknown hazards such as boulders, cliffs or crevices.
Enter NASA’s Project Morpheus, a spider-like vehicle designed to test vertical take off and autonomous landing techniques at a specially designed test area at Kennedy Space Center’s SLF.
Morpheus was conceived as as a testbed for developing technologies and techniques for enabling spacecraft to land on the Moon, asteroids or other planets while making real-time decisions to identify and avoid hazards and achieve safe touchdown unaided by controllers on Earth. Morpheus lays the foundation for capabilities that will become increasingly important in the coming years as NASA and other agencies send increasingly massive landers to Mars and eventually the outer planets.
The value of real-time hazard avoidance decision-making was displayed by the European Space Agency’s Philae spacecraft that recently landed on Comet 67P after the mission used near real-time imagery and data to attempt navigation to a safe touchdown. Even with careful planning, the small probe ended up in a shadowed region despite a successful landing and lost power less than two days later.
Technologies being developed by Morpheus and other projects will be able to eliminate this and other hazards for future spacecraft travelling to the far reaches of the Solar System.
“Once this technology goes into service, the days of having to land 20 or 30 miles (32 to 48 km) from where you really want to land for fear of the hazardous craters and rocks will be over,” said Eric Roback, ALHAT flash lidar lead engineer at NASA’s Langley Research Center in Hampton, Virginia. “Then we can land near the truly interesting science and near the critical resources that will be needed for eventual colonization, and we can do it over and over again safely.”
One of the key elements being tested is the Autonomous Landing Hazard Avoidance Technology (ALHAT). ALHAT utilizes its Hazard Detection System to steer the vehicle clear of objects on the ground that pose a risk to safe landing. The Hazard Detection System on Morpheus uses three light detection and ranging (lidar) sensors to create 3-Dimensional maps of the landing target and identify objects such as rocks and craters that must be avoided.
Morpheus determines where it is in relation to the landing target via doppler lidar and radar altimeters, providing position, altitude and velocity information to the lander’s guidance system. It uses this data to select a landing point free of surface hazards.
Failure Lays The Foundation For Success
After development and initial tether tests in 2010-2012 at NASA’s Johnson Space Center in Houston, TX, the Morpheus team brought the first experimental Vertical Takeoff / Vertical Landing (VTVL) testbed to Kennedy Space Center where the open space permit the vehicle to launched without the use of a safety tether. Unfortunately, rocket science being what it is, the lander was destroyed during a free flight test in August 2012 when it veered out of control and crashed.
Undaunted, the project commenced building a second vehicle, Morpheus Bravo, and returned to KSC’s Shuttle Landing Facility to continue flight testing.
This second Morpheus lander successfully completed a series of fourteen untethered free flight tests earlier this year, culminating in a nighttime launch and landing on May 28. The 98-second test began at 10:02 p.m. EDT with the Morpheus lander launching from the ground over a flame trench and ascending more than 800 feet.
The vehicle relied on its autonomous landing and hazard avoidance technology sensors to survey the hazard field and determine safe landing sites. Morpheus then flew forward and downward covering approximately 1,300 feet while performing a 78-foot divert to simulate a hazard avoidance maneuver.
“The flash lidar performed very well, and we could clearly identify rocks as small as one foot (0.3 m) in size from the largest range that Morpheus could give us, which was approximately a quarter mile,” Roback said. “With this sensor we could even find the safest landing site in a pitch black crater.”
Environmentally Sensitive and Cost-Effective Propulsion
The Morpheus vehicle is propelled by a liquid oxygen (LOX)/liquid methane propulsion system that can provide a specific impulse of up to 321 seconds during space flight, and these cryogenic propellants burn cleanly, are nontoxic, and can be stored easily in space. For future space missions, it may be possible to produce oxygen or methane in situ.
Oxygen is already a necessary and compatible commodity for life support systems in spacecraft, and oxygen/methane systems are being studied for power generation. LOX and methane are also readily available and relatively safe and easy to handle, permitting frequent, low-cost ground testing. These attributes and potential capabilities make propulsion with LOX/methane an attractive technology.
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