1 code implementation • 26 Mar 2024 • Ehsan Sabouni, H. M. Sabbir Ahmad, Vittorio Giammarino, Christos G. Cassandras, Ioannis Ch. Paschalidis, Wenchao Li
Unfortunately, both performance and solution feasibility can be significantly impacted by two key factors: (i) the selection of the cost function and associated parameters, and (ii) the calibration of parameters within the CBF-based constraints, which capture the trade-off between performance and conservativeness.
no code implementations • 25 Mar 2024 • Akua Dickson, Christos G. Cassandras, Roberto Tron
We propose an output feedback control-based motion planning technique for agents to enable them to converge to a specified polynomial trajectory while imposing a set of safety constraints on our controller to avoid collisions within the free configuration space (polygonal environment).
no code implementations • 20 Mar 2024 • Shirantha Welikala, Christos G. Cassandras
We consider a class of multi-agent optimal coverage problems in which the goal is to determine the optimal placement of a group of agents in a given mission space so that they maximize a coverage objective that represents a blend of individual and collaborative event detection capabilities.
no code implementations • 14 Mar 2024 • Yingqing Chen, Christos G. Cassandras, Kaiyuan Xu
This paper develops a controller for Connected and Automated Vehicles (CAVs) traversing a single-lane roundabout.
1 code implementation • 4 Jan 2024 • H M Sabbir Ahmad, Ehsan Sabouni, Akua Dickson, Wei Xiao, Christos G. Cassandras, Wenchao Li
We address the security of a network of Connected and Automated Vehicles (CAVs) cooperating to safely navigate through a conflict area (e. g., traffic intersections, merging roadways, roundabouts).
no code implementations • 1 Oct 2023 • Anni Li, Christos G. Cassandras, Wei Xiao
This paper studies safe driving interactions between Human-Driven Vehicles (HDVs) and Connected and Automated Vehicles (CAVs) in mixed traffic where the dynamics and control policies of HDVs are unknown and hard to predict.
no code implementations • 6 Aug 2023 • Kaiyuan Xu, Christos G. Cassandras
We consider the problem of scaling up optimal and safe controllers for Connected and Automated Vehicles (CAVs) from a single Control Zone (CZ) around a traffic conflict area to an entire network.
1 code implementation • 29 May 2023 • Andres S. Chavez Armijos, Anni Li, Christos G. Cassandras
This paper addresses cooperative lane-changing maneuvers in mixed traffic, aiming to minimize traffic flow disruptions while accounting for uncooperative vehicles.
no code implementations • 26 May 2023 • Ehsan Sabouni, H. M. Sabbir Ahmad, Christos G. Cassandras, Wenchao Li
We address the problem of merging traffic from two roadways consisting of both Connected Autonomous Vehicles (CAVs) and Human Driven Vehicles (HDVs).
1 code implementation • 26 May 2023 • H M Sabbir Ahmad, Ehsan Sabouni, Wei Xiao, Christos G. Cassandras, Wenchao Li
We address the security of a network of Connected and Automated Vehicles (CAVs) cooperating to navigate through a conflict area.
no code implementations • 15 May 2023 • Yingqing Chen, Christos G. Cassandras
We study the Traffic Light Control (TLC) problem for a traffic network with multiple intersections in an artery, including the effect of transit delays for vehicles moving from one intersection to the next.
no code implementations • 29 Mar 2023 • Anni Li, Andres S. Chavez Armijos, Christos G. Cassandras
We derive time and energy-optimal control policies for a Connected Autonomous Vehicle (CAV) to complete lane change maneuvers in mixed traffic.
no code implementations • 14 Mar 2023 • Yingqing Chen, Christos G. Cassandras
We study the Traffic Light Control (TLC) problem for a single intersection, considering both straight driving vehicle flows and corresponding crossing pedestrian flows with the goal of achieving a fair jointly optimal sharing policy in terms of average waiting times.
no code implementations • 10 Mar 2023 • Wei Xiao, Christos G. Cassandras, Calin A. Belta
It has been shown that optimizing quadratic costs while stabilizing affine control systems to desired (sets of) states subject to state and control constraints can be reduced to a sequence of Quadratic Programs (QPs) by using Control Barrier Functions (CBFs) and Control Lyapunov Functions (CLFs).
1 code implementation • 31 Jan 2023 • James Queeney, Erhan Can Ozcan, Ioannis Ch. Paschalidis, Christos G. Cassandras
Robustness and safety are critical for the trustworthy deployment of deep reinforcement learning.
no code implementations • 7 Nov 2022 • Ehsan Sabouni, Christos G. Cassandras
We derive an optimal index policy which prescribes the merging position of the AV within the group of HDVs.
no code implementations • 26 Sep 2022 • Ehsan Sabouni, Christos G. Cassandras, Wei Xiao, Nader Meskin
We address the problem of controlling Connected and Automated Vehicles (CAVs) in conflict areas of a traffic network subject to hard safety constraints.
2 code implementations • 28 Jun 2022 • James Queeney, Ioannis Ch. Paschalidis, Christos G. Cassandras
Data-driven, learning-based control methods offer the potential to improve operations in complex systems, and model-free deep reinforcement learning represents a popular approach to data-driven control.
no code implementations • 31 Mar 2022 • Andres S. Chavez Armijos, Rui Chen, Christos G. Cassandras, Yasir K. Al-Nadawi, Hossein Noukhiz Mahjoub, Hidekazu Araki
We derive optimal control policies for a Connected Automated Vehicle (CAV) and cooperating neighboring CAVs to carry out a lane change maneuver consisting of a longitudinal phase where the CAV properly positions itself relative to the cooperating neighbors and a lateral phase where it safely changes lanes.
no code implementations • 24 Mar 2022 • Nader Meskin, Ehsan Sabouni, Wei Xiao, Christos G. Cassandras
The safety constraints and the vehicle limitations are considered using the Control Barrier Function (CBF) framework and a self-triggered scheme is proposed using the CBF constraints.
no code implementations • 22 Mar 2022 • Ehsan Sabouni, Christos G. Cassandras, Wei Xiao, Nader Meskin
We address the problem of controlling Connected and Automated Vehicles (CAVs) in conflict areas of a traffic network subject to hard safety constraints.
no code implementations • 8 Mar 2022 • Kaiyuan Xu, Wei Xiao, Christos G. Cassandras
We consider the merging control problem for Connected and Automated Vehicles (CAVs) aiming to jointly minimize travel time and energy consumption while providing speed-dependent safety guarantees and satisfying velocity and acceleration constraints.
no code implementations • 17 Jan 2022 • Samuel C. Pinto, Shirantha Welikala, Sean B. Andersson, Julien M. Hendrickx, Christos G. Cassandras
For a given visiting sequence, we prove that in an optimal dwelling time allocation the peak uncertainty is the same among all the targets.
1 code implementation • NeurIPS 2021 • James Queeney, Ioannis Ch. Paschalidis, Christos G. Cassandras
In real-world decision making tasks, it is critical for data-driven reinforcement learning methods to be both stable and sample efficient.
no code implementations • 13 Apr 2021 • Kaiyuan Xu, Christos G. Cassandras, Wei Xiao
The paper considers the problem of controlling Connected and Automated Vehicles (CAVs) traveling through a three-entry roundabout so as to jointly minimize both the travel time and the energy consumption while providing speed-dependent safety guarantees, as well as satisfying velocity and acceleration constraints.
no code implementations • 1 Apr 2021 • Samuel C. Pinto, Sean B. Andersson, Julien M. Hendrickx, Christos G. Cassandras
We investigate the problem of persistent monitoring, where a mobile agent has to survey multiple targets in an environment in order to estimate their internal states.
no code implementations • 29 Mar 2021 • Wei Xiao, Calin Belta, Christos G. Cassandras
We define a HOCBF for a safety requirement on the unmodelled system based on the adaptive dynamics and error states, and reformulate the safety-critical control problem as the above mentioned QP.
no code implementations • 25 Feb 2021 • Shirantha Welikala, Christos G. Cassandras
This paper addresses the persistent monitoring problem defined on a network where a set of nodes (targets) needs to be monitored by a team of dynamic energy-aware agents.
no code implementations • 19 Dec 2020 • James Queeney, Ioannis Ch. Paschalidis, Christos G. Cassandras
In order for reinforcement learning techniques to be useful in real-world decision making processes, they must be able to produce robust performance from limited data.
no code implementations • 24 Sep 2020 • Shirantha Welikala, Christos G. Cassandras
We consider the problem of estimating the states of a distributed network of nodes (targets) through a team of cooperating agents (sensors) persistently visiting the nodes so that an overall measure of estimation error covariance evaluated over a finite period is minimized.
no code implementations • 9 Jul 2020 • Salomón Wollenstein-Betech, Christian Muise, Christos G. Cassandras, Ioannis Ch. Paschalidis, Yasaman Khazaeni
Usage of automated controllers which make decisions on an environment are widespread and are often based on black-box models.
no code implementations • 6 Dec 2019 • Wei Xiao, Calin A. Belta, Christos G. Cassandras
In this paper, we further improve the feasibility robustness (i. e., feasibility maintenance in the presence of time-varying and unknown unsafe sets) through the definition of a High Order CBF (HOCBF) that works for arbitrary relative degree constraints; this is achieved by a proposed feasibility-guided learning approach.
2 code implementations • 29 Oct 2016 • Jing Zhang, Sepideh Pourazarm, Christos G. Cassandras, Ioannis Ch. Paschalidis
In earlier work (Zhang et al., 2016) we used actual traffic data from the Eastern Massachusetts transportation network in the form of spatial average speeds and road segment flow capacities in order to estimate Origin-Destination (OD) flow demand matrices for the network.
Systems and Control 90B06
no code implementations • 5 Jul 2016 • Vladislav Nenchev, Christos G. Cassandras, Jörg Raisch
This paper addresses an optimal control problem for a robot that has to find and collect a finite number of objects and move them to a depot in minimum time.
no code implementations • 19 Sep 2013 • Jing Wang, Daniel Rossell, Christos G. Cassandras, Ioannis Ch. Paschalidis
We present five methods to the problem of network anomaly detection.