Motion resembling that of a pendulum undergoing large-amplitude oscillation was ob- served during a series of flight tests of an unoccupied Orion Capsule Parachute Assembly System (CPAS) drop-test vehicle. Large excursions away from vertical by the capsule could cause it to strike the ground or ocean at a large angle with respect to vertical, with an undesirable attitude with respect to heading, or with a large horizontal or vertical speed. These conditions are to be avoided because they would endanger the occupants of the capsule in an actual mission. Pendulum motion is intimately related to a parachute’s aerodynamic normal force coefficient, which is a nonlinear function of angle of attack. An analytical investigation of the dynamics of pendulum motion is undertaken with the aid of a simplified model of the physical system and the assumption that the normal force coefficient is a linear function of angle of attack in the neighborhood of a value corresponding to stable equilibrium. The analysis leads to a simple relationship for the location of a pivot point, which provides insights that are consistent with previous studies.
Linear Analysis of a Two-Parachute System Undergoing Pendulum Motion
2019 AIAA Aviation ; 2019 ; Dallas, TX, United States
2019-06-17
Aufsatz (Konferenz)
Keine Angabe
Englisch
AIAA-2019-3378: Linear Analysis of a Two-Parachute System Undergoing Pendulum Motion
British Library Conference Proceedings | 2019
|AIAA-2019-3379: Nonlinear Analysis of a Two-Parachute System Undergoing Pendulum Motion
British Library Conference Proceedings | 2019
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