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Intuitive Machines’s Odysseus module successfully lands on the Moon

The IM-1 mission brought American spacecraft, the first ever private one, back on the satellite powered by a 3D printed engine

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The IM-1 mission by Intuitive Machines, Inc. (Nasdaq: LUNR, LUNRW), a space exploration, infrastructure, and services company, lifted off on February 15th from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. After a little more than a week hurtling through space, it reached its final destination, the Moon, where the “Tardis-size” Nova-C vehicle and the Odysseus module successfully soft-landed on the surface leveraging its 3D printed engine at around 00.00 GMT. It is the first American spacecraft to land on Earth’s satellite since the Apollo missions and it’s also the first ever private one to land successfully.

The IM-1 mission is Intuitive Machines’ first attempted lunar landing as part of NASA’s Commercial Lunar Payload Services (“CLPS”) initiative, a key part of NASA’s Artemis lunar exploration efforts. The science and technology payloads sent to the Moon’s surface as part of CLPS intend to lay the foundation for human missions and a sustainable human presence on the lunar surface. The mission was defined last September when Intuitive Machines opened its AM-capable Lunar Production and Operations Facility in Houston.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket

10-years in the making

Intuitive Machines was founded in 2013, coincidentally when 3D printing began to become more accessible to engineers around the world.

Co-founders Steve Altemus, Dr. Kam Ghaffarian and Dr. Tim Crain, stepped out of the gates of NASA’s Johnson Space Center to take a shot at changing the world. In 2018, the United States declared the Moon of strategic interest and refocused NASA on returning to the Moon sustainably under the agency’s Artemis program. The following year, NASA awarded Intuitive Machines its first task order to land a suite of payloads on the surface of the Moon.

Over the next four years, Intuitive Machines built an entire space program, including its Nova-C lunar lander, mission control, and global Lunar Telemetry and Tracking Network (LTN) capable of spacecraft data transmission at lunar distance. With these assets complete, Intuitive Machines is prepared to conduct its first mission to the Moon, IM-1. From its humble beginnings on a napkin, Intuitive Machines has evolved into a diversified space exploration and infrastructure company prepared to pioneer the commercial landscape of space – with a North Star of landing on the Moon.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket

IM-1 ready

The IM-1 mission is the first U.S. vehicle to land softly on the lunar surface since Apollo 17 in 1972. Intuitive Machines selected SpaceX to launch the Company’s Nova-C class lunar lander, named Odysseus, on a SpaceX Falcon 9 rocket from NASA Kennedy Space Center’s Pad 39A. After launch, Odysseus separated from the Falcon 9 rocket on a direct trajectory to the Moon.

Intuitive Machines flight controllers working from Nova Control in Houston, Texas, planned for Odysseus to land on the Moon approximately nine days after liftoff. After touchdown, Intuitive Machines and its customers will operate payloads on the lunar surface for roughly seven days before the lunar night sets on the south pole of the Moon, rendering Odysseus inoperable.

This mission signifies not only a return to the lunar surface after a hiatus of several decades but also a bold leap into a new era of commercial lunar science and exploration. At the heart of the IM-1 mission is the Nova-C lunar lander, designed and constructed by Intuitive Machines. The lander is equipped with state-of-the-art technology, including a propulsion system powered by an environmentally friendly mix of liquid oxygen and liquid methane.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket
Nova Control was designed to resemble Star Trek’s USS Enterprise Bridge. Nova-C uses two types of radios. Vehicle health and spacecraft status operate at a speed comparable to a 1976 modem. Meanwhile, the science data radios go 16,000 times faster. Nova-C was originally designed to have a cylindrical hull. The company moved to a hexagonal structure to accommodate mass and payload integration constraints. Intuitive Machines employees’ names are etched into Nova-C’s footer to permanently stamp on the Moon.

Moon delivery

This mission’s primary objective is to deliver a variety of payloads to the Moon’s south pole region, a part of the Moon that remains unexplored. These payloads include scientific instruments and technology demonstrations that aim to pave the way for future human and robotic exploration of the Moon. The significance of the IM-1 mission extends beyond the mere act of landing on the lunar surface. It represents a pivotal moment in the ongoing narrative of space exploration, where private enterprises play an increasingly vital role.

Through NASA’s Commercial Lunar Payload Services (CLPS) initiative, the IM-1 mission is part of a broader strategy to foster a sustainable presence on the Moon, facilitating scientific discovery, resource utilization, and the development of lunar infrastructure. The payload includes Galactic Legacy Labs’ Lunaprise, an indestructible time capsule created by 3D printed watch company Barrelhand and designed to preserve humanity’s cultural heritage and knowledge. This innovative archive, capable of enduring a billion years, is a testament to our civilization’s legacy, ensuring that the essence of human achievement and wisdom is safeguarded against the ravages of time and space, etching our story indelibly on the moon’s surface.

A macro-shot of the time capsule created by Barrelhand. The Lunaprise mission objective is to establish a secure lunar repository called the Lunparise in support of Arch Missions Foundation’s billion-year archive, preserving human knowledge for eternity. These messages are called Lunagrams and can be submitted online as text, an image, or both. Music and video files are also accepted. An archive from the nonprofit Arch Mission Foundation, including the English Wikipedia, The Rosetta Project, Long Now Foundation content, Project Gutenberg content, and other cultural archive datasets are also included in the Lunaprise payload. Image courtesy: Barrelhand.

The knowledge and experience gained from this mission will be invaluable in shaping future missions to the Moon and beyond. Moreover, the IM-1 mission’s success will lay the groundwork for a burgeoning lunar economy, opening new possibilities for research, commerce, and exploration.

By advancing humanity’s capabilities to operate on the lunar surface, the mission sets the stage for more ambitious endeavors, including the establishment of lunar bases and the exploration of potential resources. The data and insights gleaned from the IM-1 mission will potentially address the challenges of living and working on the Moon, thus furthering humanity’s dream of becoming a multi-planetary species.

Nova Control is the nerve center of Intuitive Machines’ lunar mission operations in Houston, Texas. The operations center hosts mission controllers in a collaborative circular environment with access to mission-critical and support software, including the VoIP voice system. Nova Control is commercially offered, and the mission-critical command and control software, Nova Core, is developed and sustained in-house with contingency operations achieved in partnership with Fugro SpAARC in Western Australia.

Intuitive Machines has long-term agreements with ground stations across the globe that comprise its Lunar Tracking, Telemetry, and Command Network (LTN), which support S-band, X-band, and Ka-band uplink and downlink. In December 2022, Intuitive Machines validated its LDN by successfully tracking NASA’s Artemis I mission as the spacecraft reached its farthest distance from Earth.

Ahead of Artemis

Malapert A is a satellite crater to Malapert, a 69 km crater in the Moon’s south pole region. Named after Charles Malapert, a 17th-century Belgian astronomer, the area around the landing site is believed to be made of lunar highland material, similar to Apollo 16’s landing site. The IM-1 landing site is about 300 km from the Moon’s south pole. The nearby Malapert Massif is one of the 13 candidate regions being considered for NASA’s Artemis III mission.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket Shortly after launch, a spring force gently pushed Odysseus away from the launch vehicle’s second stage, allowing the lunar lander to deploy and drift away toward the Moon. Odysseus was in a standby state before separation. Break wires connected to the launch vehicle let the Nova-C spacecraft know it deployed, and a timer started on the lander to activate its primary systems. After completing the separation timing interval, Odysseus powered on, including Guidance Navigation and Control (GNC), Automated Flight Management (AFM) software, radios, and thermal control.

When Odysseus’ top deck is pointed toward the sun, this is known as max power attitude, which also helps flight controllers in Houston, Texas, manage the lander’s thermal state on the vehicle by keeping other systems in the shade of the top deck and side deck solar arrays. Each step in the commissioning process is expected to happen autonomously because flight controllers in Houston do not have communications with Odysseus yet. When autonomous commissioning is complete and max power attitude is established, Odysseus turns on its communication radios and makes first contact with flight controllers in Nova Control.

Intuitive Machines commissioned Odysseus several minutes after LVSEP autonomously. During autonomous commissioning, the lander’s GNC activated the cold-gas helium Reaction Control System (RCS) to control the vehicle’s attitude. At this point, Odysseus did not know where it’s pointed, but it could stop its spin motion, much like a person spinning in a chair with closed eyes can control the spin without knowing where it stops. After controlling the spin rate, special cameras known as star trackers autonomously matched images of the distant star field and provided Odysseus with its orientation.

Software onboard took the star tracker measurements and processed them through an algorithm known as the Kalman filter to correct the onboard orientation, known as attitude, and then estimated and rejected bad measurements. Once the GNC system autonomously determined its attitude relative to the star field, it used a reference position from the nominal launch vector to determine the approximate location of the sun. GNC then commanded RCS jets to maneuver the lander’s top deck toward the sun with a slight angle to illuminate the top deck and side solar arrays to generate maximum power.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket There are multiple steps to performing a main engine burn. The first is to flow cryogenic methane and oxygen down the lander’s feed lines to the engine to condition the propulsion system temperature; we call this chillin’ the engine. PROP monitors several automated valve and temperature readings in this process to ensure everything is progressing within the expected parameter ranges. The onboard AFM is monitoring the Time of Ignition (TIG) for the CM to begin. A few seconds before TIG, the RCS system fired jets to settle their tanks’ liquid methane and oxygen. Then, the main engine igniter comes on, much like a pilot light in a gas oven, to ignite methane and oxygen, which have been mixed in the combustion chamber by a carefully orchestrated opening of main throttle valves.

The 3D printed engine start-up sequence is something that Intuitive Machines tested thousands of times to validate safety and reliability. During CM, the vehicle held a constant attitude by adjusting the angles of the main engine inside a two-axis gimbal ring designed by the Intuitive Machines team. The automated CM sequence also throttled the main engine to give the PROP team data to make necessary adjustments across the engine’s power range. At the same time, Odysseus continued to coast toward the Moon. After autonomous commissioning, flight controllers in Nova Control prepared for the engine commissioning maneuver using Odysseus’ state-of-the-art cryogenic propulsion system.

The engine commissioning maneuver allowed flight controllers to verify engine performance and adjust the lander’s first trajectory. Odysseus was moving on a Trans-Lunar Orbit (TLO) after LVSEP on its way to the Moon before Engine Commissioning. Flight controllers on the trajectory team (TRAJ) used the signal from the lander’s communication systems to perform Orbit Determination (OD) and fire arcs of this signal data to update how fast it is moving. Minor corrections were implemented to stay on course, like a car driver making minor adjustments with the steering wheel along a straight stretch of road.

Intuitive Machines Nova-C readies for soft moon landing with a 3D printed engine, on IM-1 mission with Odysseus module on a SpaceX rocket Intuitive Machines’ Flight Dynamics Officer (FDO) used this update to calculate a direction to execute the engine Commissioning Maneuver (CM) for the best improvement in Odysseus’ trajectory to intercept the Moon. With the CM direction set by FDO, Intuitive Machines’ Flight Manager (FM) and Communications Officer (COMM) command the vehicle to rotate from max power attitude to burn attitude. Now, CM transitions control to Intuitive Machines’ Propulsion Operations (PROP) lead to begin the main engine burn.

The Nova-C class lunar lander’s three TCM burns are executed at maximum throttle, where the engine is most efficient. After each TCM, Intuitive Machines flight controllers pointed the lander’s HGA back to Earth for communication to Nova Control. Following TCM 3, the TRAJ team collaborates with FDO to finalize the OD solution crucial for updating the Lunar Orbit Insertion (LOI) maneuver. Concurrently, Odysseus’ top deck maximizes solar energy capture post-TCM 3, adopting the maximum power attitude. As LOI approached, Odysseus used its RCS to orient retrograde, directing the engine towards the Moon for optimal positioning ahead of the maneuver.

After CM, TRAJ collects data from another OD update. FDO evaluated this update and calculated how far Odysseus might be from hitting its orbit target around the Moon. FDO uses a particular coordinate system called the B-Plane, which is the mission design equivalent of the square on the backboard in basketball. If a basketball player hits the backboard square with a shot, the ball is likelier to go in the hoop. Similarly, if Odysseus hits its target on the B-Plane, it is in the right spot to be captured into lunar orbit.

LRA is a collection of eight approximately half-inch retro-reflectors – a unique collection of mirrors that is used for measuring distance – mounted to the lander. The mirror system reflects laser light directly backward to the orbiting spacecraft that emits the laser light to precisely determine the lander’s location on the surface of the Moon. LRAs are valuable because they can continue to be used as precision landmarks for guidance and navigation during the lunar day or night. A few LRAs surrounding an Artemis landing site or base camp can serve as precision landmarks to guide the arriving landers by aiding in an autonomous and safe landing.

The expected mission scenario was that each Trajectory Correction Maneuver (TCM) would be smaller than the previous one as flight controllers dial in the lander’s B-Plane target. TCM 3 was the most critical maneuver because it was the last chance flight controllers in Houston had to correct Odysseus’ trajectory before it was captured into lunar orbit. For each TCM, FDO evaluated the maneuver size needed to keep the B-Plane target in the lander’s path. If the TCM is less than the ability of Odysseus’ main engine to execute, the flight controllers may choose not to perform that TCM and make any corrections during the next opportunity.

After flight controllers loaded the final LOI maneuver solution on Odysseus, Intuitive Machines had about four hours of watching systems prepare for this maneuver. For IM-1, LOI was performed in the blind on the far side of the Moon. Flight controllers were not receiving real-time updates because there was no line-of-sight communication back to Earth. The Nova Control team counted down to LOI TIG and waited for the lander to perform its largest maneuver, between 800 and 900 meters per second, to capture into a 100 km circular Low Lunar Orbit (LLO).

This maneuver was approximately one-third of the total capability of Odysseus’ propulsion system. After the successful LOI, the Nova Control team started a cadence of activities to check the lander’s status and its systems in LLO to prepare for landing. This included calibrating Odysseus’ navigation optical cameras for lunar illumination conditions. For each lunar orbit, Intuitive Machines had about 75 minutes of communication followed by 45 minutes where the Moon blocked Odysseus’ direct line-of-sight radio link between the lander and Intuitive Machines’ ground stations.

Eaglecam is designed to deploy off of Nova-C approximately 100ft (30m) above the lunar surface and capture images as the spacecraft touches down on the Moon.

When flight controllers lose communications and are in a communications blackout, it’s called Loss of Signal (LOS). When flight controllers regain communication and are within line-of-sight, it’s called Acquisition of Signal (AOS). Odysseus orbited the Moon 12 times before descending to the surface. For Intuitive Machines, the LLO environment is more complex than the deep space environment Odysseus experienced during transit.

The Moon’s harsh environments are actively at play. When the lander is on the sunward side of the orbit, the sun heats the lander on one side, but the Moon also bakes the other side of the spacecraft with reflected infrared radiation, so Odysseus is very warm. Then, the lander passes into the lunar shadow, and the vehicle plunges into a deep cold regime and requires heater power drawn from batteries to keep systems warm.

Descent Orbit Insertion (DOI) is a small maneuver that usually happens on the far side of the Moon. The main engine fires to slow the lander so that its minimum altitude drops from 100 km to about 10 km near the landing site. The low point of an orbit around the Moon is called perilune, while the high part is apolune. In orbit, Odysseus travels faster near the peri condition and slower at the apo state. This effect is an exchange of potential energy like what people experience riding a bike through hills, coasting fast at the low points and slower at the peaks. Once DOI occurs, Odysseus is completely autonomous.

SCALPSS will capture images of the effects of the lander’s engine plume as it interacts with the lunar surface while Odysseus is descending, and as the dust plume settles after the spacecraft lands. This information is critical for validating predictive models on how particles on the lunar surface are moved by rocket engine exhaust and allows scientists to analyze the close-up imagery of the surface of the Moon. Data from SCALPSS can be used for future Artemis vehicle designs to ensure the safety of both the landers and any other surface assets nearby during landing.

The lander coasted for approximately one hour after DOI; then, the GNC system activated the main engine for Powered Descent Initiation (PDI). Odysseus reduced its velocity by approximately 1,800 meters per second to land softly on the surface of the Moon. Some lander designs have propulsion systems with multiple jets that fire on and off during descent to achieve this; however, Nova-C has a 3D printed engine designed to continuously burn and throttle from PDI until touchdown.

This approach is similar to what the Apollo descent module did. When the lander engine comes on at PDI, it is initially in a hard braking phase. The lander stays in the braking phase until approximately 2 km from the landing site. Powered Descent Initiation Terrain Relative Navigation (TRN) cameras and lasers on the lander’s downward side feed information to the navigation algorithms, which provide guidance and control. This portion may sound complicated, but it’s something humans do each time they walk, ride a bike, or drive a car. Sensors are like human eyes collecting position, velocity, and orientation data.

ILO-X is a precursor to the ILOA Hawai’i flagship Moon South Pole Observatory ILO-1. The ~0.6 kg ILO-X instruments, built for ILOA by Toronto-based Canadensys Aerospace, includes a miniaturized dual-camera lunar imaging suite (one wide field and one narrow field). It will aim to capture some of the first images of the Milky Way Galaxy Center from the surface of the Moon, as well as performing other celestial astronomy / Earth / local lunar environment observations and exploration technology validations – including functionality and survivability in the lunar environment. This mission will be the first Hawaiʻi-based organization’s cameras on the Moon. Hawaiʻi is a place that honors science, discovery and mindful exploration. The ILO-X narrow-field camera was given the name Ka ‘Imi (The Search) after a Hawai’i student naming contest. Receiving this name from the next generation of scientists of Hawaiʻi is a great honor and celebration of the unique communities and knowledge that exists on the Hawaiian Islands of which ILOA calls home.

Navigation is a brain processing this information to determine where and how you move. Guidance is similar to a human brain determining, if I am here, moving in this direction, what do I need to do to get where I want to be? The answer could be to turn left or speed up. Control is the equivalent of turning the steering wheel or stepping on the accelerator to improve the guidance command. Human eyes act as sensors, seeing how things change, and the complete cycle repeats.

Now, Odysseus is upright, with the Hazard Relative Navigation (HRN) sensors facing forward in the area where the lander intends to touch down. Intuitive Machines designed Odysseus’ trajectory to fly to the Intended Landing Site (ILS) on the Moon. Once the Nova-C class lunar lander is getting closer to its ILS, the onboard software selects a safe Designated Landing Site (DLS) with the slightest slope, free from hazards, with the range of the lander.

Odysseus’ systems matched lunar gravity to fly toward the DLS. During this time, the main engine was continually throttling down, lowering the engine power to compensate for the lander getting lighter and lighter with spend propellants spent leaving the spacecraft’s mass. Odysseus’ GNC system flew the lander to a point approximately 30 m above the DLS, and the lander went into a vertical descent at three meters per second. Then, the lander broke to a one-meter-per-second descent rate 10 meters above the surface, preparing for terminal descent and landing.

RFMG technology uses radio waves and antennae in Nova-C’s tank to measure exactly how much propellant is available. RFMG could be crucial during future long-duration missions that will rely on spacecraft fueled by cryogenic propellants, like liquid hydrogen, liquid oxygen, or liquid methane. These propellants are highly efficient but are tricky to store as they can evaporate quickly, even at low temperatures. Being able to accurately measure spacecraft fuel levels will help scientists maximize resources as NASA moves toward its goal of returning humans to the Moon through Artemis.

At this point, Odysseus used inertial measurements only. No cameras or lasers were guiding the spacecraft to the lunar surface because they would read lunar dust kicking up from the lander’s engine. Odysseus’ Inertial Measurement Unit (IMU) sensed acceleration like a human’s inner ears, which feel rotation and acceleration. Terminal descent is like walking towards a door and closing your eyes the last three feet. You know you’re close enough, but your inner ear must lead you through the door. Pitch Over with Main Engine Hazard Detection and Avoidance Vertical Descent Terminal Descent

Odysseus is designed to land at one-meter-per-second velocity. Flight controllers expected about a 15-second delay before confirming the ultimate milestone, softly landing on the surface of the Moon. It took a little more than that but now Intuitive Machines and its customers are ready to conduct science investigations and technology demonstrations for approximately the next seven days before the lunar night sets on the south pole of the Moon, rendering Odysseus inoperable.

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746 composites AM companies individually surveyed and studied. Core composites AM market generated over $785 million in 2023. Market expected to grow to $7.8 billion by 2033 at 25.8% CAGR. This new...

Davide Sher

Since 2002, Davide has built up extensive experience as a technology journalist, market analyst and consultant for the additive manufacturing industry. Born in Milan, Italy, he spent 12 years in the United States, where he completed his studies at SUNY USB. As a journalist covering the tech and videogame industry for over 10 years, he began covering the AM industry in 2013, first as an international journalist and subsequently as a market analyst, focusing on the additive manufacturing industry and relative vertical markets. In 2016 he co-founded London-based VoxelMatters. Today the company publishes the leading news and insights websites VoxelMatters.com and Replicatore.it, as well as VoxelMatters Directory, the largest global directory of companies in the additive manufacturing industry.

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