Roll Control of a Fluid-Supported Vehicle Moving in a Non-Evacuated Tube

摘要

The problem of controlling the roll angle of a high-speed vehicle moving through a tube was investigated, both for straight portions of the tube and around curves. The dynamics of the vehicle with 6 degrees of freedom were studied by postulating reasonable force characteristics for the support pads and the aerodynamic forces on the fuselage. It was shown that a de-stabilizing coupling exists between the roll and lateral modes, whereas the heave, pitch, and yaw modes are essentially uncoupled and are well-damped. However, the vehicle model studied can be stabilized by the use of a feedback torque about the roll axis proportional to the derivative of the roll-angle error. During a curve, the roll-angle error can be sensed by using a pendulum mounted in the vehicle in conjunction with a rate gyro. For straight portions of the tube only the rate gyro measurement is required. In addition to the feedback torque, the vehicle's roll angle is varied by an appropriately chosen open-loop torque as it passes through a curve. The results of digital and analog simulations are presented. (Author)