ADAPTIVE PRACTICAL OUTPUT MANEUVERING CONTROL FOR A CLASS OF NONLINEAR SYSTEMS

This paper deals with the adaptive practical output maneuvering control problems for a class of nonlinear systems with uncontrollable unstable linearization. The objective is to design a smooth adaptive maneuvering controller to solve the geometric and dynamic tasks with an arbitrary small steady tracking error. The method of adding a power integrator and the robust recursive design technique are employed to force the system output to track a desired path and make the tracking speed to follow a desired speed along the path. An example is considered and simulation results are given. The proposed design procedure can be illustrated by the use of this example.

The output torque estimation of MCMG for agile satellites

Studied in this paper are the attitude control law design and the output torque estimation problem of micro control moment gyros （MCMGs） for the agile satellites executing rapid attitude maneuver mission. An algorithm is proposed for estimating the output torques and the gimbal angular rates of MCMGs, which can help engineers to choose reasonable size for actuators so that the cost of satellite can be decreased. According to some special maneuver missions, a numerical example of attitude control system for a small satellite with MCMGs in pyramid configuration is studied, and the simulation results validate the proposed estimation algorithm.

NEW OPTIMAL LARGE ANGLE MANEUVER STRATEGY FOR SINGLE FLEXIBLE LINK

A component synthesis vibration suppression (CSVS) method for flexible structures is put forward. It can eliminate any unwanted orders of flexible vibration modes while achieves desired rigid motion. This method has robustness to uncertainty of frequency, which makes it practical in engineering. Several time optimal and time-fuel optimal control strategies are designed for a kind of single flexible link. Simulation results validate the feasibility of our method.

Cicada(Tibicen linnei) steers by force vectoring

To change flight direction, flying animals modulate aerodynamic force either relative to their bodies to generate torque about the center of mass, or relative to the flight path to produce centripetal force that curves the trajectory. In employing the latter, the direction of aerodynamic force remains fixed in the body flame and rotations of the body redirect the force. While both aforementioned techniques are essential for flight, it is critical to investigate how an animal balances the two to achieve aerial locomotion. Here, we measured wing and body kinematics of cicada （Tibicen linnei） in flee flight, including flight periods of both little and substantial body reorientations. It is found that cicadas employ a common force vectoring technique to execute all these flights. We show that the direction of the half-stroke averaged aerodynamic force relative to the body is independent of the body orientation, varying in a range of merely 20 deg. Despite directional limitation of the aerodynamic force, pitch and roll torque are generated by altering wing angle of attack and its mean position relative to the center of mass. This results in body rotations which redirect the wing force in the global flame and consequently change the flight traiectorv.

Maneuver control of the hypersonic gliding vehicle with a scissored pair of control moment gyros

A maneuver control approach using a scissored pair of control moment gyros is proposed to improve the penetration ability of a hypersonic gliding vehicle(HGV) with a relatively high lift-drag ratio. Then, a multivariable strong coupling nonlinear bank-toturn dynamical model is established for the case of lateral maneuvering of an HGV equipped with a scissored pair of control moment gyros. According to the requirement of coordinated turning of the HGV in a lateral maneuver, a decoupling controller based on feedback linearization and a linear quadratic optimal algorithm is designed. Finally, the large airspace maneuvering trajectories of the HGV including S-shaped, cycloid and spiral maneuvering modes are designed by applying overload control technology. Simulations demonstrate that the designed maneuvering trajectory significantly increases the airspace range and flexibility of the vehicle. The coordinated turn control system achieves an accurate and rapid tracking of the maneuvering trajectories in large airspace.