Set Of Control Laws Research Articles

Accelerated Flight Control LAW Clearance Using Stores Grouping Concept

Current fighter aircraft are demanded to feature multirole capability with large number of different external stores to be integrated on the aircraft. These stores represent air to air, air to surface weapons etc., which have wide range of aerodynamic characteristics as well as different mass properties (CG, mass, inertia). This conflicts with the requirement of adequate stability, optimum handling qualities, superior agility and robustness characteristics over the entire flight envelope. Especially with an unstable aircraft it is impossible to fulfill these requirements for all stores with just one set of control laws. Therefore, automatic reconfiguration in control laws based on similar flight dynamic characteristics is carried out. Stores grouping concept is often used to reconfigure the flight control laws with store information in order to normalize/optimize the flight dynamics characteristics and corresponding support towards flight clearance. The flight clearance is a tedious procedure as a host of criteria need to be evaluated at a large number of nominal flight conditions for different airframe configurations, multiples thereof with tolerances and failures. This paper describes how various stores configurations can be grouped together in order to accelerate the clearance process.

Distributed Control Method for Economic Dispatch in Islanded Microgrids With Renewable Energy Sources

The economic dispatch in islanded microgrids (MGs) is a thorny problem due to the low equivalent inertia and the uncertainty of environmental conditions. In this paper, a two-layer model is proposed for economic dispatch in islanded MGs, in which an MG is considered as the lower layer, while a communication network is considered as the upper layer. Furthermore, a systematic method is presented to derive fully distributed control laws from any given communication network. On the communication network, there are two subgraphs, G̃ and Ĝ, one of which consists of all agents, while the other of which consists of only controllable agents. Correspondingly, two sets of control laws are derived from the two subgraphs, where the control laws from the subgraph G̃ ensure the supply-demand balance in the MG, while the control laws from the subgraph Ĝ realize the economic dispatch. Moreover, the economic operation in MGs can be satisfied, only if agents on the communication network regulate distributed generators iteratively according to the control laws. Finally, three cases are designed to evaluate the performance of the method, and the simulation results verify the effectiveness of the proposed method.

On the relationship between the <i>energy shaping</i> and the <i>Lyapunov constraint based</i> methods

In this paper, we make a review of the controlled Hamiltonians (CH) method and its related matching conditions, focusing on an improved version recently developed by D.E. Chang. Also, we review the general ideas around the Lyapunov constraint based (LCB) method, whose related partial differential equations (PDEs) were originally studied for underactuated systems with only one actuator, and then we study its PDEs for an arbitrary number of actuators. We analyze and compare these methods within the framework of Differential Geometry, and from a purely theoretical point of view. We show, in the context of control systems defined by simple Hamiltonian functions, that the LCB method and the Chang's version of the CH method are equivalent stabilization methods (i.e. they give rise to the same set of control laws). In other words, we show that the Chang's improvement of the energy shaping method is precisely the LCB method. As a by-product, coordinate-free and connection-free expressions of Chang's matching conditions are obtained.

Aeroservoelastic Test of the Subsonic Ultra-Green Aircraft Research Truss-Braced Wing Model

The Subsonic Ultra Green Aircraft Research Truss-Braced Wing aeroservoelastic wind-tunnel test was conducted in the NASA Langley Transonic Dynamics Tunnel. The primary goals of the test were to identify the open-loop flutter boundary and then demonstrate flutter suppression. A secondary goal was to demonstrate gust load alleviation. Open-loop flutter and limit cycle oscillation onset boundaries were identified for a range of Mach numbers and various angles of attack. Two sets of control laws were designed for the model, and both sets of control laws were successful in suppressing flutter. Control laws optimized for gust load alleviation were not designed; however, the flutter suppression control laws were assessed using the Transonic Dynamics Tunnnel airstream oscillation system. This paper describes the experimental apparatus, procedures, and results of the truss-braced wing wind-tunnel model test. Acquired system identification data used to generate aeroservoelastic models are also discussed.

Coordinated optimal target realization for linear systems allowing choice-based actions

Summary This paper studies target-reaching problems for systems controlled by multiple agents in which every agent implements control based on the choice selected independently from a private choice set. The agents' choices jointly determine the system target to be reached, and all the possible choice combinations define a set of targets to be reached. Without exchanging choice information among the agents, the existence of a set of control laws to realize all the targets in a given target set is a nontrivial question. For linear systems, the necessary and sufficient condition is shown hinged on a compatibility condition on the target set. Under the compatible condition, coordinated optimal control laws are derived such that any target in the target set can be achieved. Copyright © 2015 John Wiley & Sons, Ltd.

Integrated, Distributed Traffic Control in Multidomain Networks

In this paper, we put forward an integrated traffic control structure and the associated control laws for multidomain networks. This control structure performs per-edge-to-edge-based multinext-hop or multipath rate adaptation and load balancing among domain edge nodes in a multidomain network. This control structure is underpinned by a large family of distributed control laws, with provable convergence and optimality properties. With any user-defined global design objective, a set of control laws can be selected from this family of control laws that track an operational point where the global design objective is achieved, while providing traffic engineering (TE) and fast failure recovery (FFR) features for class-of-service (CoS)-aware flow aggregates. The structure allows the user to have full control over how the domains should be created and whether to use point-to-multipoint and/or point-to-point multipath. The flexibility and versatility of the control structure makes it an ideal theoretical underpinning for the development of integrated traffic control solutions for large-scale networking systems, in particular, software-defined networks in which the data plane is fully programmable via a well-defined south-bound interface, such as OpenFlow. The simulation testing demonstrates the viability of the solution in providing TE, FFR, and CoS features.

Flocking of multi-agents with time delay

This article consider the flocking of multi-agents with time delay. Both leader free and virtual leader available are considered. For leader free, a set of control laws is proposed, and it is proved that the agent velocities become the same asymptotically, and avoidance of collisions between the agents is ensured. For virtual leader available, a set of control laws that relies on the state information and the external signal is proposed. With the control laws all agents can follow the virtual leader.

Stability results for switched controller systems

There are many practical control problems where the control action is determined by switching among a given set of control laws. This paper presents necessary and sufficient conditions to test for quadratic stabilizability and for robust stabilizability with a quadratic storage function for switched controller systems. Algorithms which can be used to construct appropriately stabilizing control laws are also presented.

Sliding Modes: the Case of Multivariable Systems Nonlinear in the Inputs

Abstract Here is considered the problem of the synthesis of control laws generating well defined sliding modes of systems which are nonlinear in the controls, a problem which is actually open. The notions of compatibility and regularity of a pair (F, S)are introduced, where F is a family of vector fields, S is a smooth embedded submanifold of the state space. For regular and compatible pair ( F, S) one constructs a finite set of control laws which generate well defined sliding modes with S as attractive sliding manifold. An example is given.