At NASA’s Kennedy Space Center (KSC) in Florida, at the northern edge of the former Shuttle Landing Facility (SLF), is an area that looks very much like the surface of the Moon, complete with rocks and craters to serve as a site to flight test the agency’s Morpheus prototype planetary lander. A total of 14 free flight tests have been conducted so far, the last of which took place under cover of darkness on May 28, 2014, and although Free Flight 14 (FF14) concluded Project Morpheus’ flight test campaign the team feels there are some areas they can improve upon, and so operations are again in full swing for a new series of flight tests, the first of which is currently scheduled to take place on Tuesday, Nov. 18, 2014.
“Since our last flight, the team’s engineers have been reviewing the volumes of data we collected during all the free flights. The analysis enhanced our understanding of the underlying performance of the Autonomous Landing and Hazard Avoidance Technology (ALHAT) system and revealed some areas that we felt were important to improve upon at this stage rather than waiting for a later flight implementation,” says Dr. Jon Olansen, Morpheus project manager at Johnson Space Center (JSC).
Morpheus, which has been in development under a strict budget since 2010, is a testbed and technology demonstrator for the development of planetary landers that will, in the future, be capable of accessing hard-to-reach areas on missions to destinations such as the Moon, Mars, or even an asteroid. The vehicle, which some would say resembles a UFO, has conducted many dozens of successful static hot-fire tests and tethered-flight tests at JSC in Houston, but the vehicle’s development has not come easily. In August 2012, during its second free-flight test at KSC, Morpheus Alpha crash landed moments after lift-off—an accident blamed on a malfunction that resulted in the total loss of the vehicle.
Project Morpheus pressed on to design and build a new upgraded prototype vehicle, Morpheus Bravo, utilizing the lessons learned from the crash, and in the time since Morpheus has had one success after another, excelling at exceedingly difficult and higher flights to prove the technology.
The Vertical Takeoff / Vertical Landing (VTVL) technology used on Morpheus is not something new, as the Apollo Lunar Modules were the first planetary landers to utilize it. ALHAT, on the other hand, comprises a new set of innovative technologies that would allow a future planetary lander to autonomously identify its landing area by creating 3-D maps of the surface on the fly, while being able to navigate and avoid hazardous terrain and ensuring a safe landing for future missions.
The work being done with the Morpheus Lander could lead to the development of planetary landers capable of reaching many places previously thought as inaccessible, like the Moon’s polar regions or deep craters on Mars, and Morpheus’ successful flights are a positive sign for a developing capability that could make future missions to those places a reality.
Morpheus’ last flight on May 28, 2014, was similar to previous tests, except it was done at night and was conducted with a finer-tuned ALHAT based on what was learned in FF13 to navigate Morpheus’ entire approach with ALHAT in closed-loop mode. Morpheus jumped skyward to an altitude of about 800 feet, solely using ALHAT’s Hazard Detection System for guidance, and—assisted by three light detection and ranging (lidar) sensors—the system detected rocks and craters on the ground before performing a safe landing a quarter mile away.
“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,” said Eric Roback, ALHAT flash lidar lead engineer at NASA’s Langley Research Center in Hampton, Va. “With this sensor we could even find the safest landing site in a pitch black crater.”
Now, nearly six months later, after a lengthy post-flight analysis, data review, and evaluation of Morpheus and its ALHAT performance, the team is ready to fly Morpheus again. All of the required vehicle modifications are now complete, and so Morpheus is scheduled for a tethered flight test this week to exercise all of its systems before proceeding to the next round of free flight tests in December.
“The tests we flew last spring successfully met all the objectives we had established for demonstrating integrated Lox/Methane propulsion and precision landing advances using ALHAT,” says Olansen. “The rationale for pursuing now is to fully demonstrate the system-level performance that would more readily enable infusion into future spaceflight missions. As a result, we developed a number of software updates, primarily to the navigation algorithms. We also designed hardware improvements, including relocating the Doppler lidar velocimeter to eliminate the interference from heated air due to the engine plume. The combination of identified modifications provide a sufficiently different ALHAT capability that warrants demonstration in the closed-loop flight environment that Morpheus provides.”
“The expectation is that these flights will establish the ALHAT suite with a TRL6 level of maturity, thereby reducing the development risk that future missions would have to endure in order to incorporate any of the components in their flight design,” added Olansen.
Morpheus’ propellant is a mixture of “green,” non-toxic liquid oxygen/liquid methane fuel, which is stored inside the lander’s four spherical propellant tanks. Future missions to the Moon and Mars could potentially produce these elements through in-situ resource utilization, thus largely mitigating the need for carrying all the necessary fuel required from Earth, and though the current Morpheus prototype vehicle is relatively small, having a payload capacity of 500 kg, the Morpheus team hopes to scale it up in the future to accommodate both crew and cargo.
“The first intent would more than likely be a robotic-type of mission, and depending on the path forward, and vehicles out there to get us beyond Low-Earth Orbit (LEO), the ALHAT technology and other Morpheus technologies could be part of that – at least we HOPE,” said Roback earlier this year. “So basically it’s not really the ‘Lander design’ as the intended tests for us, but rather the technologies we tested on these vehicles. If we were to continue testing, we’d probably use different vehicle designs as well.”
“Once this technology goes into service, the days of having to land 20 or 30 miles from where you really want to land for fear of the hazardous craters and rocks will be over,” added Roback. “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.”
Three flight tests are scheduled for the rest of the year, with the first tethered test expected on Nov. 18, weather permitting. Assuming all goes well, the team hopes to free fly Morpheus twice more during the first two weeks of December, with each of those flights following the same trajectory profile as FF10-14 did last spring.