Application of matrix calculus to the problem of space-flight dynamics

1981 ◽  
Vol 17 (12) ◽  
pp. 1116-1123
Author(s):  
V. S. Gubenko ◽  
V. V. Kravets
2018 ◽  
Vol 148 ◽  
pp. 268-275 ◽  
Author(s):  
Carlos Montalvo ◽  
Bruce Wiegmann
Keyword(s):  

2019 ◽  
Vol 8 (2S11) ◽  
pp. 4043-4046

Objectives: DLR’s real-time Human-in-the-Loop Space Flight Simulator needed an enhancement in its transonic and supersonic behavior for its advanced concept of a suborbital, hypersonic, winged passenger transport called SpaceLiner. Methods/Statistical analysis: A simulation model has been developed by geometry modeled flight dynamics for the commercial flight simulation software “X-Plane”. The presented solution is based on a real-time flight dynamics corrector application, taking table-based aerodynamic coefficients from Computational Fluid Dynamics (CFD) model experiments to overwrite X-Plane’s internal flight dynamics in the supersonic and hypersonic regime. Findings: Although compressible flow effects are considered using Prandtl-Glauert, the SpaceLiner X-Plane simulation model needed deeper investigation in its transonic and supersonic behavior, taking into account that transonic effects in X-Plane only refer to an empirical mach-divergent drag increase and the airfoil becomes an appropriate thickness ratio diamond shape under supersonic conditions. Whereas the X-Plane internal flight simulation engine delivers a high level of realism under subsonic conditions, significant deviations from the SpaceLiner aerodynamic reference database were identified in the supersonic and hypersonic regimes. An improved accuracy could be observed for two Mach test cases under corrector application usage conditions. Using X-Plane on the one hand and covering a constant accuracy throughout the whole range of regimes, subsonic, supersonic and hypersonic on the other hand, can be achieved by using the presented corrector application solution. Application/Improvements: X-Plane’s wireframe model approach was successfully fused with table-based lookup processing, delivering a constant high level of realism throughout the whole Mach range.


Author(s):  
Walter J. Sapp ◽  
D.E. Philpott ◽  
C.S. Williams ◽  
K. Kato ◽  
J. Stevenson ◽  
...  

Space flight, with its unique environmental constraints such as immobilization, decreased and increased pressures, and radiation, is known to affect testicular morphology and spermatogenesis. Selye, summarized the manifestations of physiological response to nonspecific stress and he pointed out that atrophy of the gonads always occurred. Reports of data collected from two dogs flown in space for 22 days (Cosmos 110) indicate that there was an increase of 30 to 70% atypical spermatozoa when compared to ground based controls. Seventy-five days after the flight the abnormalities had decreased to the high normal value of 30% and mating of these dogs after this period produced normal offspring, suggesting complete recovery. Effects of immobilization and increased gravity were investigated by spinning rats and mice at 2x g for 8-9 weeks. A decrease in testicular weight was noted in spun animals when compared to controls. Immobilization has been show to cause arrest of spermatogenesis in Macaca meminstrins.


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