Touchdown dynamic modeling and simulation of lunar lander
In this paper, the key influences of lunar lander landing model are illuminated systematic. Then the touchdown dynamic model of lunar module is built. And the simulation model for lunar landing described on ADAMS is discussed. As an example, one kind of lunar module model with four cantilever truss style landing gear is built by ADAMS and the simulations are focused on the influences on landing by the characteristics of buffers in primary and secondary struts of the landing gear. The conclusions can be used for the design of lunar lander.
Monte Carlo approach to touchdown dynamics for soft lunar landings
Abstract : Results of analytical touchdown dynamics investigations are presented which were conducted to obtain estimates of the probability of stable landing for configurations with various landing gear diameters. Both three-legged and four-legged vehicles are considered in the analysis. Dynamic scaling considerations are taken into account so that the results are applicable to a wide range of vehicle size and mass. A Monte Carlo approach is taken in the determination of initial landing conditions. Results indicate that for a given probability of stable landing, a three-legged vehicle requires a landing gear diameter only slightly larger than the diameter required for a four-legged vehicle. Therefore the three-legged vehicle's landing gear should weigh less.
Handling Qualities and Trajectory Requirements for Terminal Lunar Landing, as Determined from Analog Simulation
QUALITLES AND TRAJECTORY REQUIREMENTS FOR TERMINAL LUNAR LANDING, AS DETERMINED FROM ANALOG SIMULATION A six-degree-of-freedom analog study was performed to aid in defining handling qualities and trajectory potential for terminal lunar landing. Results showed that, for a maneuvering task in the pitch mode and a random-motion-correction task in the roll and yaw modes, the pilots referred rate or attitude command with control accelerations of about 10 deg/sec and reasonable artificial damping. Also, to consistently perform successful landings, the pilots generally used thrust-to-weight ratios throttled between a minimum value of 0.8 lunar g and a maximum value of 1.8 lunar g.