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Distributed Nonlinear Trajectory Optimization for Multi-Robot Motion Planning

Ferranti, L. (author), Lyons, L. (author), Negenborn, R.R. (author), Keviczky, T. (author), Alonso-Mora, J. (author)

This work presents a method for multi-robot coordination based on a novel distributed nonlinear model predictive control (NMPC) formulation for trajectory optimization and its modified version to mitigate the effects of packet losses and delays in the communication among the robots. Our algorithms consider that each robot is equipped with an...

journal article 2023

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Microscopic Traffic Modeling Inside Intersections: Interactions Between Drivers

Zhao, J. (author), Knoop, V.L. (author), Wang, M. (author)

Microscopic traffic flow models enable predictions of traffic operations, which allows traffic engineers to assess the efficiency and safety effects of roadway designs. Modeling vehicle trajectories inside intersections is challenging because there is an infinite number of possible paths in a two-dimensional space, and drivers can...

journal article 2023

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Optimal Trajectory Planning for Mitigated Motion Sickness: Simulator Study Assessment

Jain, V. (author), Kumar, Sandeep Suresh (author), Papaioannou, G. (author), Happee, R. (author), Shyrokau, B. (author)

In the transition from partial to high automation, occupants will no longer be actively involved in driving. This will allow the use of travel time for work or leisure, where high comfort levels preventing motion sickness are required. In this paper, an optimal trajectory planning algorithm is presented in order to minimise motion sickness in...

journal article 2023

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Simple framework for systematic high-fidelity gate operations

Russ, M.F. (author), Philips, S.G.J. (author), Xue, X. (author), Vandersypen, L.M.K. (author)

Semiconductor spin qubits demonstrated single-qubit gates with fidelities up to 99.9 % benchmarked in the single-qubit subspace. However, tomographic characterizations reveal non-negligible crosstalk errors in a larger space. Additionally, it was long thought that the two-qubit gate performance is limited by charge noise, which couples to the...

journal article 2023

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Flexibility Framework With Recovery Guarantees for Aggregated Energy Storage Devices

Evans, Michael (author), Tindemans, Simon H. (author), Angeli, David (author)

This paper proposes a framework for the procurement of flexibility reserve from aggregated storage fleets. It allows for arbitrary tree structures of aggregation hierarchy, as well as easily implementable disaggregation via broadcast dispatch. By coupling discharge and recovery modes, the proposed framework enables full-cycle capacity to be...

journal article 2022

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OpenAP.top: Open Flight Trajectory Optimization for Air Transport and Sustainability Research

Sun, Junzi (author)

Trajectory optimization has been an active area of research for air transport studies for several decades. But almost all flight optimizers proposed in the literature remain close-sourced, which presents a major disadvantage for the advancement of scientific research. This optimization depends on aircraft performance models, emission models, and...

journal article 2022

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Efficient Bang-Bang Model Predictive Control for Quadcopters

Westenberger, Jelle (author), de Wagter, C. (author), de Croon, G.C.H.E. (author)

Time-optimal model predictive control is important for achieving fast racing drones but is computationally intensive and thereby rarely used onboard small quadcopters with limited computational resources. In this work, we simplify the optimal control problem (OCP) of the position loop for several maneuvers by exploiting the fact that the...

journal article 2022

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An optimal control approach of integrating traffic signals and cooperative vehicle trajectories at intersections

Liu, M. (author), Zhao, J. (author), Hoogendoorn, S.P. (author), Wang, M. (author)

An integrated approach for optimising traffic signals and cooperative vehicle trajectories at urban intersections is proposed. The upper layer determines the optimal signals using enumeration and the lower layer optimises trajectories under each feasible signal plan. In the lower layer, platoon accelerations are optimised considering comfort...

journal article 2021

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Optimal Control Strategies for Seasonal Thermal Energy Storage Systems with Market Interaction

Lago, Jesus (author), Suryanarayana, Gowri (author), Sogancioglu, Ecem (author), De Schutter, B.H.K. (author)

Seasonal thermal energy storage systems (STESSs) can shift the delivery of renewable energy sources and mitigate their uncertainty problems. However, to maximize the operational profit of STESSs and ensure their long-term profitability, control strategies that allow them to trade on wholesale electricity markets are required. While control...

journal article 2021

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Learning Optimal Controllers for Linear Systems with Multiplicative Noise via Policy Gradient

Gravell, Benjamin (author), Mohajerin Esfahani, P. (author), Summers, Tyler H. (author)

The linear quadratic regulator (LQR) problem has reemerged as an important theoretical benchmark for reinforcement learning-based control of complex dynamical systems with continuous state and action spaces. In contrast with nearly all recent work in this area, we consider multiplicative noise models, which are increasingly relevant because...

journal article 2021

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A Graphical Measure of Aggregate Flexibility for Energy-Constrained Distributed Resources

Evans, Michael (author), Tindemans, Simon H. (author), Angeli, David (author)

We consider the problem of dispatching a fleet of heterogeneous energy storage units to provide grid support. Under the restriction that recharging is not possible during the time frame of interest, we develop an aggregate measure of fleet flexibility with an intuitive graphical interpretation. This analytical expression summarises the full set...

journal article 2020

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Proxy functions for Approximate Reinforcement Learning

Alibekov, Eduard (author), Kubalík, Jiří (author), Babuska, R. (author)

Approximate Reinforcement Learning (RL) is a method to solve sequential decisionmaking and dynamic control problems in an optimal way. This paper addresses RL for continuous state spaces which derive the control policy by using an approximate value function (V-function). The standard approach to derive a policy through the V-function is...

journal article 2019

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Minimising Unserved Energy Using Heterogeneous Storage Units

Evans, Michael P. (author), Tindemans, Simon H. (author), Angeli, David (author)

This paper considers the optimal dispatch of energy-constrained heterogeneous storage units to maximize security of supply. A policy, requiring no knowledge of the future, is presented and shown to minimize unserved energy during supply-shortfall events, regardless of the supply and demand profiles. It is accompanied by a graphical means to...

journal article 2019

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Mission-Driven Resource Management for Reconfigurable Sensing Systems

de Groot, T.H. (author), Krasnov, O.A. (author), Yarovoy, Alexander (author)

Modern sensors, such as multifunctional radars, comprise many settings and the number of controllable settings is increasing due to technological advance. Although having many settings allows many capabilities, it simultaneously requires an automatic manager to control them. This paper proposes mission-driven resource management to control...

journal article 2018

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A string-based representation and crossover operator for evolutionary design of dynamical mechanisms

Kuppens, P.R. (author), Wolfslag, W.J. (author)

Robots would perform better when their mechanical structure is specifically designed for their designated task, for instance by adding spring mechanisms. However, designing such mechanisms, which match the dynamics of the robot with the task, is hard and time consuming. To assist designers, a platform that automatically designs dynamical...

journal article 2018

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The individual time trial as an optimal control problem

De Jong, Jenny (author), Fokkink, R.J. (author), Olsder, G.J. (author), Schwab, A.L. (author)

In a cycling time trial, the rider needs to distribute his power output optimally to minimize the time between start and finish. Mathematically, this is an optimal control problem. Even for a straight and flat course, its solution is non-trivial and<br/>involves a singular control, which corresponds to a power that is slightly above the aerobic...

journal article 2017

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Optimal model distributions in supervisory adaptive control

Ghosh, D. (author), Baldi, S. (author)

Several classes of multi-model adaptive control schemes have been proposed in literature: instead of one single parameter-varying controller, in this adaptive methodology multiple fixed-parameter controllers for different operating regimes (i.e. different models) are utilised. Despite advances in multi-model adaptive control theory, the question...

journal article 2017

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Optimal control via reinforcement learning with symbolic policy approximation

Kubalík, Jiří (author), Alibekov, Eduard (author), Babuska, R. (author)

Model-based reinforcement learning (RL) algorithms can be used to derive optimal control laws for nonlinear dynamic systems. With continuous-valued state and input variables, RL algorithms have to rely on function approximators to represent the value function and policy mappings. This paper addresses the problem of finding a smooth policy...

journal article 2017

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Trajectory driven multidisciplinary design optimization of a sub-orbital spaceplane using non-stationary Gaussian process

Dufour, R. (author), De Meulenaere, J. (author), Elham, A. (author)

This paper presents the multidisciplinary optimization of an aircraft carried sub-orbital spaceplane. The optimization process focused on three disciplines: the aerodynamics, the structure and the trajectory. The optimization of the spaceplane geometry was coupled with the optimization of its trajectory. The structural weight was estimated using...

journal article 2015

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Operational model for vessel traffic using optimal control and calibration

Shu, Y. (author), Daamen, W. (author), Ligteringen, H. (author), Hoogendoorn, S.P. (author)

Due to the ever-increasing economic globalization, the scale of transportation through ports and waterways has increased sharply. As the capacity of maritime infrastructure in ports and inland waterways is limited, it is important to simulate vessel behavior to balance safety and capacity in restricted waterways. Currently many existing vessel...

journal article 2015