Alignment with the Vision for Space Exploration: Green Flag

The benefit of this project to both lunar and Mars exploration is well aligned with the goals of the VSE. These technological advances, given the virtual guarantee that mission software will increase in complexity and requirements for reliability, will all be enabling for a Mars mission as well as the lunar mission.



The primary objective of the Autonomous Landing and Hazard Avoidance Technology (ALHAT) project is to develop and mature various hardware and software components that will aid lunar descent vehicles. Overall, the goal is for the system to enable safe, accurate, and precise landing near selected landing sites anywhere on the lunar surface unaided by humans. The primary customer for the technology is the Lunar Lander Projects Office.


The technology that the ALHAT project develops includes hardware and software components. Some of the hardware components are locally developed sensors such as flash lidar (Light Detection and Ranging), scanning lidar, optical Doppler lidar, and cameras, whereas other components are commercially available sensors (inertial motion units, star trackers, and altimeters). The software components include algorithms to convert sensor data to vehicle-state information, algorithms that aid vehicle flight, and guidance and navigation algorithms. The TRL for the overall system varies. Some sensors can be considered to be at TRL 3 or 4 (flash lidar), whereas others have flown in space but have not been employed for lunar landing scenarios (scanning lidar). The algorithms range from TRL 3 to TRL 5. The current team is composed of personnel from JSC, LaRC, JPL, the Charles Stark Draper Laboratory, and Johns Hopkins University Applied Physics Laboratory. Moreover, there is some university and industry involvement (by the University of Texas at Austin, Utah State University, Jacobs Engineering Group, Inc., and Fastmetrix, Inc.).


Quality: Gold Star

The quality of the NASA development effort on the ALHAT project is high. The team has the experience and expertise to carry out the technology development. Moreover, the team is working in a tightly coordinated manner. It has reported several major accomplishments and significant findings, ranging in scope from technical achievements, to vendor site visits, to written operation concept reports, to independent reviews of the ALHAT project.

The team has recognized several technology areas that had not previously been identified. These include a need for sensors that can provide real-time elevation maps of terrain during descent; a need to increase and improve the operational range, accuracy, and resolution of flash lidar; and a need for a velocimeter that can provide accurate and precise horizontal velocity measurements. It is noteworthy that the team has identified these gaps and plans to address each one by the Lunar Lander PDR in the year 2011.

The broader community is involved in this project; however, there is room for additional involvement. Facilities at LaRC, JPL, and JSC are being used and are adequate to advance to TRL 5. Achieving TRL 6 will require free-flier tests.

Effectiveness in Developing and Transitioning: Green Flag

The technology roadmap for the ALHAT project shows a systems engineering approach to problem solving. Continued development of hardware and software technology is planned, with significant milestones set for June

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