Control of a falling body with a mathematical model for unsteady aerodynamic force

摘要

Motion of a freely oscillating body like pendulum has been measured, modeled, and controlled. This problem models oscillation of a falling body with parachute, which is subject to gravitational and aerodynamic forces. We have used a wind tunnel with its exit section vertically inclined, where a model can oscillate about a fixed joint above the exit. Two air jets were employed to control the oscillation and emitted in the direction of motion or in the opposite direction.