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Navigation Doppler Lidar (NDL), Psionic-built copy of the engineering test unit

Griffin Mission One · manifested · lander system

A lidar landing sensor (an optical head with three telescopes and an electronics chassis) that measures the lander's velocity and its altitude above the ground during descent. Psionic built this unit under its NASA license as a copy of NASA Langley's NDL engineering test unit, the design that flew on Peregrine and IM-1. On Griffin it is part of the lander, its primary altimeter, not a NASA payload.

PI: not applicable (a lander component). NDL's inventor and NASA lead: Farzin Amzajerdian (NASA Langley); Psionic's founder Steve Sandford and chief engineer Diego Pierrottet came from the Langley NDL work.
Built by: Psionic (Hampton, Virginia), which licensed NDL from NASA in 2016, building NASA Langley's engineering-test-unit design for Astrobotic (now Voyager Lunar Systems) (company)
Technology landing sensor (Doppler lidar)
Moon Base need #1101 (The study's reading, as for the IM-1 and Peregrine units: gap #1101 and the Users Guide's landing challenge do not name NDL, but the challenge asks for landing systems that take accurate range and velocity measurements over low-visibility terrain, which is what NDL does. Griffin-1 would be the first landing on which NDL is the lander's own primary altimeter at the South Pole.)
Route onto CLPS commercial; Not a payload selection: Astrobotic chose NDL for its own lander and had Psionic build the unit. NASA had assigned NDL to Astrobotic's Peregrine in January 2020, where Astrobotic used it as its primary navigation sensor; for Griffin the unit is Astrobotic's purchase from Psionic. When Astrobotic ordered it, and on what terms, is not public; by December 2024 Langley said the Psionic build would fly on Griffin.
Timeline first funding 2005 (Langley proof of concept, NDL design line); 2016 (Psionic license); first flight test 2008-08 (helicopter, NDL line); 2017-04 (FO Xodiac, third generation); this unit: not in public sources; selected not in public sources (Langley said by December 2024 that the Psionic build would fly on Griffin); launch target late 2026 (NASA, Aug 2026); landing not in public sources
On the Moon not yet flown
FO tested

Flights before the Moon

  • aircraft (not FO): Helicopters at NASA Dryden (2008) and Kennedy (2012), ALHAT project, 2008-08 and 2012-12. Early NDL prototypes: real-time altitude and velocity against GPS and inertial navigation.

"conducted a series of helicopter flight test campaigns in August 2008 at NASA Dryden (now Armstrong) Flight Research Center"
— NTRS 20250010290, page 9

  • NASA test vehicle: Morpheus rocket-powered test lander, Kennedy, ALHAT project, 2014. Second-generation NDL on six flights, the last three in the closed-loop navigation. FO's NDL page dates the Morpheus flight 2012.

"The ALHAT project conducted six flight tests of the NDL sensor on the rocket powered Morpheus test vehicle at KSC in 2014"
— NTRS 20250010290, page 9

  • FO: Masten (now Astrobotic) Xodiac rocket-powered lander, Mojave, in NASA's COBALT payload (TechPort 91351), 2017-04-06 and 2017-04-13. The third-generation NDL, open-loop: the effect of real landing-vehicle dynamics on NDL. Its lessons went into the engineering test unit design that this unit copies.

Data: date: Apr 6 and Apr 13, 2017
— FO annual report, FY2017, flights of TechPort project 91351 (flight table)

"The third-generation NDL model"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"The lessons learned from this testing were critical in design, build, and testing of an NDL Engineering Test Unit"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

  • FO: Masten (now Astrobotic) Xodiac, Mojave: Psionic's own commercial NDL (FO technology T0256, TechPort 106687), 2020-09-10. Psionic's version of NDL on simulated lunar-lander maneuvers; it helped Psionic validate its algorithms and data processing. Not the engineering-test-unit design, but the same builder.

"Flight Test: Sep. 10, 2020"
— Flight Tests Advance Commercialization of NASA Navigation

"The flight test helped Psionic validate their algorithms and data processing to verify the accuracy of these measurements."
— Flight Tests Advance Commercialization of NASA Navigation

"The flight test added to data collected on"
— nasa.gov: dr-fop-pub-anr-20-03-fop-accomp-report-online.pdf, FY2020 report p. 4

  • FO: Blue Origin New Shepard, in NASA's SPLICE payload (FO technology T0269, TechPort 106705), 2020-10-13 and 2021-08-26. A sister engineering test unit (ETU #2). The rocket's helium environment limited the NDL data.

Data: date: Oct. 13, 2020
— FO annual report, FY2021, flights of TechPort project 106705 (p. 8)

Data: date: Aug. 26, 2021
— FO annual report, FY2021, flights of TechPort project 106705 (p. 9)

"The SPLICE project flew NDL sensors on the Blue Origin New Shepard suborbital rocket on two flights in 2020 and 2021"
— NTRS 20250010290, page 9

  • aircraft (not FO): Aircraft flight tests (type not stated), NDL ETU #1, 2021-2023. A sister engineering test unit in aircraft tests and integrated tests with other avionics.

"# 1: Aircraft flight tests (2021 - 2023)"
— NTRS 20230008771, page 10

  • Earth orbit or deep space: Astrobotic's Peregrine Mission One (NDL ETU #4, the lander's primary navigation sensor), 2024-01-08. The same design on the same company's lander, in space for 6.5 hours of nominal operation. Peregrine's propulsion failed, so it never did its landing job.

"NDL operated nominally for 6.5 hours"
— NTRS 20240016238, slide 11

"# 4 – Lunar Landing Demonstration onboard Astrobotic lander (2024)"
— NTRS 20240016238, slide 9

  • earlier lunar mission: Intuitive Machines' IM-1 (NDL ETU #3, a NASA payload), 2024-02-22. The same design through a lunar descent: valid range and velocity data from 10 km to the surface.

"NDL provided 100% valid measurements from 10 km to the Moon's surface"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"# 3 – Lunar Landing Demonstration onboard Intuitive Machines lander (2024)"
— NTRS 20240016238, slide 9

  • aircraft (not FO): NASA Armstrong F/A-18, Psionic's own NDL (PSNDL) in a test pod, 2025-02-20 to 2025-02-24. Psionic's own version, not this unit: navigation data in highly dynamic maneuvers up to the speed of sound, for lunar and Mars descent. FO's pages describe it next to the FO test, but it was a NASA Armstrong test, not an FO flight.

"Flight Test: Feb. 20-24, 2025"
— Flight Tests Advance Commercialization of NASA Navigation

"Psionic’s NDL system was flight tested at NASA’s Armstrong Flight Research Center in Edwards, California, on an F/A-18 Hornet aircraft"
— Flight Tests Advance Commercialization of NASA Navigation

Heritage hardware

  • design heritage (copy of NASA's engineering test unit): NASA built four NDL engineering test units of one design: ETU #1 (aircraft tests), #2 (New Shepard), #3 (IM-1) and #4 (Peregrine). The Griffin unit is a fifth of the same design, built by Psionic. ETU #4 was Astrobotic's primary navigation sensor on Peregrine, so Griffin's lander team has integrated this design before.

"4 ETUs have been built"
— NTRS 20230008771, page 10

"identical to the one flown on both the Astrobotic Peregrine and Intuitive Machines Odysseus CLPS missions"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

Funding before the lunar flight

  • The NASA NDL design line, which this unit copies: Langley seed money for a proof of concept (2005), ALHAT and Morpheus (second generation), COBALT (third generation, 2013-2017) and SPLICE, which built the engineering test units (STMD Game Changing Development). Amounts not public; the IM-1 record lists the 2016-2019 parts orders that name NDL. (NASA Langley; STMD and HEOMD projects (ALHAT, COBALT, SPLICE); 2005-2023): amount not in public sources

"In 2005, he and his team received funding from Langley to put together a proof of concept."
— NASA’s Laser Navigation Tech Enables Commercial Lunar Exploration - NASA

"NASA’s Space Technology Mission Directorate (STMD) further matured the NDL technology as part of the Safe and Precise"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"The NDL sensor development was supported by multiple NASA program offices including the Space Technology Mission Directorate"
— NTRS 20250010290, Acknowledgments

  • Building this unit: Psionic, for Astrobotic, under Psionic's 2016 exclusive NASA license and Space Act Agreements. The price and who paid it are not in public sources; no NASA contract names the Griffin unit. (commercial (Astrobotic purchase); NASA license and Space Act Agreements; not in public sources): amount not in public sources

"In 2016, he worked with NASA’s Technology Transfer program to exclusively license the NDL technology."
— Flight Tests Advance Commercialization of NASA Navigation, Background

"Psionic also entered into a Space Act Agreement to leverage NASA facilities and expertise"
— Flight Tests Advance Commercialization of NASA Navigation, Background

  • Not this unit: NASA money to Psionic for its own, smaller NDL versions (PNDL, PSNDL). USAspending lists six NASA contracts to Psionic (UEI JPNARELTCEN6), among them 80NSSC22C0014, 'Compact commercial Navigation Doppler Lidar with photonic-integrated-circuit upgrades' ($6,731,332 obligated, 2022-2027), 80NSSC23CA180 (CCRPP, 'NDL System on Module', $2,499,101) and SBIR 80NSSC25C0433 (PSNDL component qualification, $3,997,571). Spinoff says NASA also backed Psionic through Game Changing Development projects. These fund Psionic's versions, not the copy of NASA's unit, so no amount is entered here. (NASA SBIR, CCRPP and STMD contracts to Psionic (own versions); 2020-2027): amount not in public sources

"COMPACT COMMERCIAL NAVIGATION DOPPLER LIDAR WITH PHOTONIC-INTEGRATED-CIRCUIT UPGRADES"
— USAspending.gov, award 80NSSC22C0014, description; obligated 6731332.0; 2022-01-13 to 2027-11-15

"CCRPP - NAVIGATION DOPPLER LIDAR SYSTEM ON MODULE"
— USAspending.gov, 80NSSC23CA180, amount 2499101.0

"FY25 SBIR PHASE II SEQUENTIAL - PSNDL COMPONENT QUALIFICATION FOR CLASS A MISSIONS"
— USAspending.gov, 80NSSC25C0433, amount 3997571.0

"has also bolstered the company’s efforts through multiple Small Business Innovation Research contracts and Game Changing Development program projects"
— Softer Moon Landings for Companies

How it got onto CLPS

"Astrobotic has also integrated NDL into its lunar lander for Griffin Mission One."
— Transitions of Flight Tested Technologies

"Our team recently finished integrating Navigation Doppler LiDAR (NDL) with Griffin-1"
— NDL Integrated with Griffin-1, Astrobotic, 30 Apr 2026

"Astrobotic: NDL was the primary navigation sensor Not a CLPS payload"
— NTRS 20240016238, slide 10 (Peregrine)

"NDL is a flight-controlled guidance and navigation sensor but is not considered a NASA CLPS payload."
— NASA press kit, Commercial Lunar Payload Services Initiative: Astrobotic's Peregrine Mission One…, Peregrine

On the Moon

Delivered to Astrobotic and integrated into Griffin-1 by April 2026. Astrobotic says each integration step is tested in software, on a mobile FlatSat and in helicopter and Xodiac tests, without saying which NDL unit flew. It would be the first NDL to serve as a lander's own primary landing sensor through a full lunar descent: Peregrine's unit never descended, and IM-1's landing used no NDL data.

"has been assembled and delivered by Psionic to Astrobotic for their upcoming Griffin Mission One"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"including software-in-the-loop, testing with our mobile FlatSat, helicopter and Xodiac rocket testing, and full system simulations"
— NDL Integrated with Griffin-1

"the attempt proved to be unsuccessful and the vehicle conducted its landing without the use of any NDL data"
— NTRS 20250010290, page 11 (IM-1)

FO's role

Grade: tested. Grade unchanged from the study's earlier traceback (fo-tested), with the caveat it already carries: FO did not fly this unit. It flew the direct predecessor of its design (2017), a sister engineering test unit (2020-2021) and Psionic's own NDL version (2020). FO's page says the 2017 Xodiac flights gave 'a unique environment for examining the effect of landing vehicle dynamics on the NDL operation', and their lessons were 'critical in design, build, and testing of an NDL Engineering Test Unit', the design this unit copies. For Psionic, the 2020 flight 'added to data collected on previous VTVL testing' toward 'flight-ready NDL units'. Manifested, not landed.

FO flights: 5. Two Xodiac flight days in 2017, one Xodiac flight for Psionic in 2020, and two New Shepard flights in 2020-2021 shared with other payloads (and part of NASA's Tipping Point with Blue Origin). Their cost is in FO records, not in public sources.

"The rocket-powered Xodiac vehicle provided a unique environment for examining the effect of landing vehicle dynamics on the NDL operation."
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"The lessons learned from this testing were critical in design, build, and testing of an NDL Engineering Test Unit"
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"During a flight test supported by Flight Opportunities, Psionic’s version of NASA’s NDL flew on Astrobotic’s (then Masten Space Systems) Xodiac vertical takeoff vertical landing system in Mojave, California."
— Flight Tests Advance Commercialization of NASA Navigation

"Psionic Navigation Doppler LIDAR: Precision Navigation Sensor for Lunar Missions"
— TechPort project 106687, title (FO, Psionic, 2019-2021)

"SPLICE (Safe & Precise Landing Integrated Capabilities Evolution)"
— TechPort project 106705, title (FO, JSC, 2020-2023)

"Navigation Doppler Lidar, a copy built by Psionic"
— earlier finding of this study (not a public source)

Who built it

"A copy of the NDL engineering test unit (identical to the one flown on both the Astrobotic Peregrine and Intuitive Machines Odysseus CLPS missions) has been assembled and delivered by Psionic to Astrobotic for their upcoming Griffin Mission One."
— Moon Mission for Flight-Tested Navigation Doppler Lidar

"Psionic built the same device, under its license, to be the primary altimeter for another CLPS mission, Astrobotic’s Griffin lander"
— Softer Moon Landings for Companies, Spinoff, published 30 Dec 2025

"Psionic build of NDL ETU will be flown on Astrobotic’s Griffin mission"
— NTRS 20240016238, conclusion slide (Langley, AIAA SciTech 2025)

"After retiring from NASA, Sandford formed Psionic in Hampton, Virginia."
— Flight Tests Advance Commercialization of NASA Navigation, Background

Moon Base need

"Develop precision landing systems capable of taking highly accurate range and velocity"
— Moon to Mars knowledge base: Moon Base technology and knowledge challenges, Headline challenge 1

"technologies should enable safe and accurate landings in all visibility conditions"
— Moon to Mars knowledge base: ESDMD #1101: Lunar Precision Landing and Hazard Avoidance for Human Exploration, description

Open questions

  • Has the Psionic-built Griffin unit, or an NDL test unit, flown on Astrobotic's helicopter or Xodiac tests? Astrobotic lists such tests for its integration work without naming the unit.
  • What did Astrobotic pay Psionic for the unit, and did NASA fund any of it? Not in public sources.
  • When did Astrobotic order the unit? Not in public sources; Langley's slides of December 2024 say it will fly on Griffin.
  • Spinoff calls it Griffin's 'primary altimeter'; does Griffin also use it as a primary velocity sensor, as Peregrine did? Not in public sources.
  • What FO paid for the 2017, 2020 and 2020-2021 flights: FO records.