Yi Jianqiang

Controller design for flying boats taking off from water with regular waves

As a special airplane, a flying boat can take off from water and land in water, which makes its controller design more complicated than that of other general airplanes. Based on the mathematical model of a flying boat, two controllers applying classical PID (Proportional Integration Differential) method and a compound control method (combining active-disturbance rejection controller (ADRC) and dynamic inversion (DI) methods) are designed respectively. Then the performances of the two controllers are validated by tracking a speed step signal from 15m/s to 16m/s in clam water, holding the speed and the pitch angle of the flying boat in water with regular waves, and taking off from water with and without waves. The results of the simulations show that the controllers can improve the stability and seakeeping quality of the flying boat.

Controller design based on T-S fuzzy reasoning and ADRC for a flying boat

Flying boat is a fixed-wing airplane capable of landing and taking off on water, and its performance, evaluated by its sea-keeping ability, strongly depends on sea conditions. A Flying boat with good sea-keeping ability can reduce impacts from waves and runs safely and smoothly under a certain sea state. However, sea-keeping ability is still the key problem that hinders its development and application. In this paper, based on the mathematical model of a flying boat, a simulation system predicting the motions of the flying boat on an irregular wave is built, and a controller deduced by active disturbance rejection control (ADRC) and Tagaki-Sugeno (T-S) fuzzy reasoning is applied to improve the sea-keeping ability. The simulation results show that the flying boat has good performances for tracking the surface of waves, reducing impact from water, and making the flying boat take off on three water conditions safely (calm water, water with regular wave and water with irregular wave respectively).

Modeling longitudinal aerodynamic and hydrodynamic effects of a flying boat in calm water

The researches of flying boats have been carried on for about a hundred years, and there are lots of flying boats used all around the world for different tasks. In this paper, the modeling of a flying boats longitudinal motion was researched. By analyzing the flying boats geometrical, kinematical and dynamical characters, its hydrodynamic coefficients were approximated by the semi-empirical method which came from Savitskys researching results of planing boats motion predication. Based on the form of the flying boat, some corrections to the Savitskys method were made to get a better approximation. The aerodynamic∗ coefficients of the flying boat were obtained by some wind tunnel tests. Based on these results, the longitudinal nonlinear mathematical model of the flying boat in calm water was built. At last, a comparison of the taking-off process between the simulation results and existing experimental data was made. The results showed that the mathematical model was consistent with the actual flying boat.

A Blended Autopilot for Dual Control Missile Using Generalized Predictive and Adaptive Terminal Sliding Mode Control

Abstract A blended autopilot algorithm is developed using generalized predictive control and adaptive non-singular terminal sliding mode control, for dual control missile steered by combination of aerodynamic fins and reaction jets. The blended algorithm considers the reaction jets control design prior due to its inherent control error, and then treats the aerodynamic fin control on the basis of the reaction jets control results. The generalized predictive control method is applied to the reaction jets control, which could make the missile achieve desired performance with a small number of consumed reaction jets. Then a novel adaptive non-singular terminal sliding mode control method is proposed for the aerodynamic control system design, to meet the requirements of robustness and fast response for the control of the missile. The unknown bound of the uncertainties and disturbances is estimated adaptively in the control, which makes the control with better robustness. Using the Lyapunov stability theory, the finite time convergence in both reaching and sliding phases is achieved. Finally, the simulations are conducted on the nonlinear longitudinal missile model with uncertainties and disturbances, and the simulation results demonstrate the effectiveness of the blended autopilot algorithm.

A discontinuous control method for dynamical positioning of underactuated surface vessels

For a second-order nonholonomic constraint exists in underactuated surface vessel system, which makes thesystem not meet the Brocketts necessary condition, there is no continuously differentiable control law that can make the origin of the system asymptotically stable. After coordinate and feedback transformations, the stable feedback control laws are respectively proposed for two subsystems with finite-time control method, and then the dynamical positioning control problem is well solved by a discontinuous way. Results of computer simulation show the effectiveness of the proposed control method.

Robot Planning with Ant Colony Optimization Algorithms

Ant colony optimization algorithms are investigated in this paper for robot planning in configuration space. The robot planning problem is to find a feasible path from a beginning to a goal while avoiding obstacles in a clustered environment. Lots of attentions have been paid on such problems, but little is with the ant colony optimization algorithms. Originated from the max-min ant system (MMAS) algorithm for traveling salesman problem, a modified ant colony optimization algorithm for robot planning is proposed. The algorithm has some distinguished features, such as a path pruning mechanism, etc. The optimal solution can be achieved effectively in different environments with a high probability.