ITS Berkeley

Viability-Based Computations of Solutions to the Hamilton-Jacobi-Bellman Equation

Bayen, Alexandre M.
Claudel, Christian
Saint-Pierre, Patrick
Bemporad, Alberto
Bicchi, Antonio
2007

This article proposes a new capture basin algorithm for computing the numerical solution of a class of Hamilton-Jacobi-Bellman (HJB) partial differential equations (PDEs) [3], based on a Lax-Hopf formula [2]. The capture basin algorithm is derived and implemented to perform numerical computations. Its performance is measured with highway data obtained for interstate I80 in California.

Traffic Flow Reconstruction Using Mobile Sensors and Loop Detector Data

Herrera, Juan C.
Bayen, Alexandre M.
2007

In order to develop efficient control strategies to improve traffic conditions on freeways, it is necessary to know the state of the freeway at any point in time and space. Using data collected from stationary detectors –such as loop detector stations– the density field can be currently reconstructed to a certain accuracy. Unfortunately, deploying this type of infrastructure is expensive, and its reliability varies. This article proposes and investigates new algorithms that make use of data provided by mobile sensors, in addition to that collected by stationary detectors, to reconstruct...

Modeling and Optimization Analysis of Single Flagellum Bacterial Motion

Lobaton, Edgar
Bayen, Alexandre M.
2007

Bacteria such as Rhodobacter sphaeroides use a single flagellum for propulsion and change of orientation. Simple organisms such as this have inspired nanorobotic designs with potential applications in medicine which motivates the present work. In this article, an elastic model for a single flagellum bacterium is presented and followed by an analysis of the system based on optimization. The model is based on the method of Regularized Stokeslet which allows for a discretization of the system into particles which are connected by spring forces. An optimal elasticity distribution that...

Comparison of the Performance of Four Eulerian Network Flow Models for Strategic Air Traffic Management

Sun, Dengfeng
Strub, Issam
Bayen, Alexandre M.
2007

Four Eulerian network models are implemented to model high altitude air traffic flow. Three of the models use the framework of discrete time dynamical systems, while the fourth consists of a network of partial differential equations. The construction of these models is done using one year of air traffic data. The four models are applied to high altitude traffic for six Air Route Traffic Control Centers in the National Airspace System and surrounding airspace. Simulations are carried out for a full day of data for each of the models, to assess their predictive capabilities. The models’...

Robust Feasibility for Control of Water Flow in a Reservoir-Canal System

Amin, Saurabh
Bayen, Alexandre M.
El Ghaoui, Laurent
Sastry, Shankar
2007

A robust control problem for distant downstream control of a reservoir-canal system modeled by Saint-Venant equations is investigated. The problem is to regulate the release of water at the upstream end such that the measured water level (or stage) at the downstream end does not deviate outside of prescribed bounds under the effect of downstream perturbations. Under the assumption of small perturbations, the Saint-Venant model is linearized around a steady state flow. The resulting linear model is discretized to obtain a linear state-space model using a method of characteristics based...

Computation of Solutions to the Moskowitz Hamilton-Jacobi-Bellman Equation Under Viability Constraints

Bayen, Alexandre M.
Claudel, Christian
Saint-Pierre, Patrick
2007

This article proposes a new capture basin algorithm for computing the numerical solution of a class of Hamilton-Jacobi-Bellman (HJB) partial differential equations (PDEs), based on a Lax-Hopf formula. The capture basin algorithm is derived and implemented to perform numerical computations of constrained solutions. The rate of convergence of this first order algorithm is assessed experimentally using an analytical benchmark problem. Finally, its performance is measured with highway data obtained for interstate 180 in California.

Parameter Identification for the Shallow Water Equation Using Modal Decomposition

Wu, Qingfang
Amin, Saurabh
Munier, Simon
Bayen, Alexandre M.
Litrico, Xavier
Belaud, Gilles
2007

A parameter identification problem for systems governed by first-order, linear hyperbolic partial differential equations subjected to periodic forcing is investigated. The problem is posed as a PDE constrained optimization problem with data of the problem given by the measured input and output variables at the boundary of the domain. By using the governing equations in the frequency domain, a spatially dependent transfer matrix relating the input variables to the output variables is obtained. It is shown that by considering a finite number of dominant oscillatory modes of the input, an...

On Stability of Switched Linear Hyperbolic Conservation Laws with Reflecting Boundaries

Amin, Saurabh
Hante, Falk M.
Bayen, Alexandre M.
Egerstedt, Magnus
Mishra, Bud
2008

We consider stability of an infinite dimensional switching system, posed as a system of linear hyperbolic partial differential equations (PDEs) with reflecting boundaries, where the system parameters and the boundary conditions switch in time. Asymptotic stability of the solution for arbitrary switching is proved under commutativity of the advective velocity matrices and a joint spectral radius condition involving the boundary data.