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This paper proposes a hybrid Nonlinear Dynamic Inversion (NDI) control method for the high angle of attack super-maneuverable flight control. In the post-stall flight regime, the problems of nonlinearity, time varying, coupling and uncertainties would arise, which is a big challenge for the flight control method. A hybrid NDI control method based on the angular acceleration feedback control is proposed...
In this paper a Parallel Manipulator (Stewart Platform) is used to align and maintain the position of the photovoltaic panels in relation to the Sun. The system is designed on a Stewart platform with two degrees of freedom providing a significant advantage towards reaching the maximum accuracy and economy for this positioning task. To avoid measurement the velocity of the system a new adaptive type...
We develop a fast distributed algorithm, termed DEXTRA, to solve optimization problems when N agents reach agreement and collaboratively minimize the sum of their local objectives over the network, where the communications between agents are described by a directed graph. Existing algorithms, including Gradient-Push (GP) and Directed-Distributed Gradient Descent (D-DGD), solve this problem restricted...
This paper begins to bridge theoretical systems control with satellite communications in fundamental ways. In view of satellite system controllers, quality of service of user terminals needs a radically different perspective to reliably maintain a minimum adaptive link margin to account for link state uncertainties. Special emphasis is therefore given to the cost-variance, discrete-time control theory...
This paper presents a method for estimating the maximum lateral tire-road friction coefficient and wheel side slip angle based on the pneumatic trail information that exhibits unique characteristics according to the road surface conditions. The high sensitivity of the pneumatic trail for the wheel side slip angle enables the proposed observer to detect the peak tire-road friction coefficient in low...
In this paper, an optimal ensemble control under dynamic constraints is designed based on multidimensional radau pseudospectral method (MRPM) for inhomogeneous robots. The optimal control scheme exploits the uniform control inputs to steer the robots to the desired distribution while compensating the inhomogeneity of robots. A controllable ensemble system is constructed, in which velocity and acceleration...
This research investigates the viability of detecting vehicle road departure via the measurements of anomalies in vehicle dynamics, especially under conditions when left and right tires experience imbalance of forces (split-μ condition). This approach is based on established low-order vehicle models to facilitate real-time implementation. Vehicle states are obtained from an INS system to obtain real-time...
This paper presents a novel control strategy for an Unmanned Aerial Vehicle subject to state and input constraints. The method consists in pre-stabilizing the system dynamics and then using an Explicit Reference Governor to ensure constraint satisfaction by suitably manipulating the applied reference. The control scheme is initially designed under some simplifying assumptions and is then tuned to...
This work focuses on the design of estimation algorithms able to identify the interconnection topology of a class of modular aerial vehicles obtained by rigidly interconnecting a number of actuator and payload modules. The idea is to obtain a composable aerial vehicle that can be easily assembled and then deployed on the selected application scenario without a priori knowledge of the exact final geometric...
This paper examines the degree to which optimizing a lithium-ion battery's cycling for parameter identifiability can improve the robustness of subsequent health-conscious, model-based battery control. The paper builds on two established bodies of literature showing that (i) battery trajectory optimization for identifiability can improve parameter estimation accuracy significantly, and (ii) model-based...
We study the Maximal Admissible Set (MAS) of a linear difference inclusion under a chance constraint involving random variables with bounded support. After showing that it is difficult to compute this set in general, we suggest inner and outer approximations that can be computed using existing algorithms. The inner approximations are themselves constraint admissible sets and can be represented by...
Recently distributed integral controllers relying on averaging and communication have been proposed as effective means for optimal frequency regulation in power systems, load balancing of network flows, and as natural extensions to static consensus controllers. Typically, only the questions of stability, disturbance rejection, and steady-state resource allocation are addressed in the literature, and...
We study robust control policies for DC power networks with flexible line susceptances, or weights, subject to perturbations in supply-demand vector. The margin of robustness for a given control policy is defined as the radius of the largest `1 ball in the space of balanced perturbations under which the link flows can be asymptotically contained within their specified limits. We propose an optimization...
Synchronization of nonlinear oscillators is a ubiquitous phenomenon in the biological sciences; however, existing analytical techniques are ill-equipped to handle the large amount of heterogeneity present in realistic populations of biological oscillators. Using phase reduction, we derive upper and lower bounds on the critical coupling strength required to achieve frequency synchronization in a population...
MEMS technology is being investigated to improve the performance, integration and cost of nanopositioning systems. The most basic MEMS fabrication processes produce designs etched into a single layer of silicon and electrostatic transduction is often seen as the most viable actuation and sensing technology. This work provides a method to utilize the same electrostatic drive for both actuation and...
This work describes a new method for autonomous mode-matching and quadrature nulling of a Microelectromechanical system (MEMS) wineglass mode gyroscope, utilizing particle swarm optimization. Use of this derivative-free optimization scheme allows for multi-objective optimization of gyroscopic performance parameters. Modal frequency split and both mode shapes' quadrature and amplitude were optimized...
The controllability of a dynamical system or network describes whether a given set of control inputs can completely exert influence in order to drive the system towards a desired state. Structural controllability develops the canonical coupling structures in a network that lead to un-controllability, but does not account for the effects of explicit symmetries contained in a network. Recent work has...
This paper considers a class of convex optimization problems where both the objective function and the constraints have a continuous dependence on time. We develop an interior point method that asymptotically succeeds in tracking the optimal point in nonstationary settings. The method utilizes a time-varying constraint slack and a prediction-correction structure that relies on time derivatives of...
The alternating direction method of multipliers (ADMM) is applied to constrained quadratic optimization of intensity-modulated radiation therapy (IMRT) planning. The proximal operator for the ADMM algorithm is developed, and the algorithm is applied to different clinical treatment sites (liver, prostate, and head & neck). The results are compared with the solutions obtained by several other commercial...
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