Apollo 11 Lunar Module Touchdown Dynamics Reconstruction Verification and Validation for Human Landing Systems

This paper presents an updated high-fidelity lunar landing dynamics simulation test bed developed at NASA Marshall Space Flight Center (MSFC) in support of the Human Landing System (HLS) program, with verification support from NASA Langley Research Center (LaRC). The MSFC GeneraLized Aerospace Simulation in Simulink® (GLASS) program uses MATLAB®/Simulink® and Simscape™ Multibody™ to model detailed contact dynamics of lunar regolith, shock absorbers, footpads, and multibody linkages, laying the groundwork for integrated analyses incorporating in-the-loop guidance, navigation, and control systems. For validation, the simulation focuses on pure landing dynamics and is benchmarked against Apollo 11 flight data and independent modern reconstructions.

The GLASS simulation demonstrates excellent agreement with historical Apollo data, validating the approach against real-world landing dynamics. Further, strong correlation between the MSFC and LaRC simulation results across different platforms provides verification of the modeling methodology. This collaborative effort establishes confidence in the simulation framework and provides a solid foundation for comprehensive HLS system analysis. The paper details the modeling methodology, validation against Apollo data, and verification through comparison with Zupp’s reconstruction and LaRC’s MSC Automated Dynamic Analysis of Mechanical Systems (Adams) reconstruction results.