Data

Guaranteed Bounds for Traffic Flow Parameters Estimation Using Mixed Lagrangian-Eulerian Sensing

Claudel, Christian G.
Bayen, Alexandre M.
2008

This article proposes a new method combining convex optimization and viability theory for estimating traffic flow conditions on highway segments. Traffic flow is modeled by a Hamilton-Jacobi equation. Using a Lax-Hopf formula, we formulate the necessary and sufficient conditions for a mixed boundary and internal conditions problem to be well posed. The well-posedness conditions result in a system of linear inequalities, which enables us to compute upper and lower bounds on traffic flow parameters as the solution to a linear program. We illustrate the capabilities of the method with a data...

Stability Analysis of Linear Hyperbolic Systems with Switching Parameters and Boundary Conditions

Amin, Saurabh
Hante, Falk M.
Bayen, Alexandre M.
2008

We study asymptotic stability of an infinite dimensional system that switches between a finite set of modes. Each mode is governed by a system of one-dimensional, linear, hyperbolic partial differential equations on a bounded space interval. The switching system is fairly general in that the space dependent system matrix functions as well as the boundary conditions may switch in time. For the case in which the switching occurs between subsystems in canonical diagonal form, we provide two sets of sufficient conditions for asymptotic stability under arbitrary switching signals. These results...

Feed-Forward River Flow Control Using Differential Flatness

Di Meglio, Florent
Rabbani, Tarek
Litrico, Xavier
Bayen, Alexandre M.
2008

The rarefaction of global water resources is a motivation for research on automation of management of water distribution systems. Large amounts of fresh water are lost due to poor management of open-channel systems. This article focuses on the management of such canals which are used to convey water from the resource (generally a dam located upstream) to a specific downstream location. Due to the fluctuations of water needs, water demand changes with time. This change in demand calls for the efficient operation of the open-channel systems to avoid overflows and to supply desired flow rates...

Ensemble Kalman Filter Based State Estimation in 2D Shallow Water Equations Using Lagrangian Sensing and State Augmentation

Tossavainen, Olli‐Pekka
Percelay, Julie
Tinka, Andrew
Wu, Qingfang
Bayen, Alexander M.
2008

We present a state estimation method for two-dimensional shallow water equations in rivers using Lagrangian drifter positions as measurements. The aim of this method is to compensate for the lack of knowledge of upstream and downstream boundary conditions in rivers that causes inaccuracy in the velocity field estimation by releasing drifters equipped with GPS receivers. The drifters report their positions and thus provide additional information of the state of the river. This information is incorporated into shallow water equations by using Ensemble Kalman Filtering (EnKF). The proposed...

Boundary Data Reconstruction for Open Channel Networks Using Modal Decomposition

Wu, Q.
Litrico, X.
Bayen-Poisson, Aurélie
2008

This article presents a method to estimate flow variables for an open channel network governed by first-order, linear hyperbolic partial differential equations and subject to periodic forcing. The selected external boundary conditions of the system are defined as the model input; the flow properties at internal locations, as well as the other external boundary conditions, are defined as the output. A spatially-dependent transfer matrix in the frequency domain is constructed to relate the model input and output. A data reconciliation technique efficiently eliminates the error in the...

Preface

Bastin, George
Bayen, Alexandre M.
2009

Management of canal networks at the age of information technology. With the miniaturization of sensors and their decreasing costs, the paradigm of instrumentation of the built infrastructure and the environment has now been underway for several years, leading to numerous successful and sometimes spectacular realizations such as the instrumentation of the Golden Gate with wire- less sensors a few years ago. The convergence of communication, control and sensing on numerous platforms including multi-media platforms has enabled engineers to augment physical infrastructure systems with an...

Guaranteed Bounds on Highway Travel Times Using Probe and Fixed Data

Claudel, Christian G.
Bayen, Alexandre M.
2009

This article investigates the problem of incorporating mobile probe data collected from GPS equipped cell phones into estimation algorithms for travel time. We use kinematic wave theory to create a modeling framework capable of incorporating trajectory data into the model. The problem of including loop detector data in this model is performed using a standard approach available in the literature. The problem of fusing this data with probe data is formulated using the Moskowitz function, which results from kinematic wave theory. Using this formulation, two linear programs are posed to...

Data reconciliation of an open channel flow network using modal decomposition

Wu, Qingfang
Litrico, Xavier
Bayen, Alexandre M.
2009

This article presents a method to estimate flow variables for an open channel network governed by the linearized Saint-Venant equations and subject to periodic forcing. The discharge at the upstream end of the system and the stage at the downstream end of the system are defined as the model inputs; the flow properties at selected internal locations, as well as the other external boundary conditions, are defined as the outputs. Both inputs and outputs are affected by noise and we use the model to improve the data quality. A spatially dependent transfer matrix in the frequency domain is...

Viability-based computation of spatially constrained minimum time trajectories for an autonomous underwater vehicle: Implementation and experiments

Tinka, A.
Diemer, S.
Bayen, Alexandre M.
2009

A viability algorithm is developed to compute the constrained minimum time function for general dynamical systems. The algorithm is instantiated for a specific dynamics (Dubin's vehicle forced by a flow field) in order to numerically solve the minimum time problem. With the specific dynamics considered, the framework of hybrid systems enables us to solve the problem efficiently. The algorithm is implemented in C using epigraphical techniques to reduce the dimension of the problem. The feasibility of this optimal trajectory algorithm is tested in an experiment with a light autonomous...