Jan P. Maschuw

LMI-based control of vehicle platoons for robust longitudinal guidance

Abstract This paper presents a novel approach to control layout for longitudinal guidance of platoons with a limited number of vehicles. It accounts for both the reduction of spacing errors and a limitation in velocities and accelerations of following vehicles to avoid saturations. All criteria can be expressed using a mixed H2/H∞ problem formulation. The objectives are formulated as one set of linear matrix inequalities that are solved for the controller. The optimization is presented for different control structures and the effectiveness of reducing overshoots in velocities or accelerations is shown through simulation results. This work also considers structural constraints concerning the information available to the controller and evaluates a sequential control algorithm applying the same layout method. Finally, the effects of changing parameters of the vehicles drivetrain are analyzed and robustness of the presented controllers is investigated.

PIDrobust Toolbox - Performance Tuning for PID Controlled Time Delay Systems with Parameter Uncertainties

Abstract Most of the PID controller tuning rules for time delay LTI systems existing today use only time delay approximations and ignore parameter uncertainties in the modeled system. This article presents a toolbox for parameter optimization and loop shaping for PID parameter tuning with explicit consideration of the time delay and the parameter uncertainties of the system. In addition a root locus method for time delay systems is implemented. All tuning methods use the nominal model to formulate the performance requirements. During the subsequent optimization, the parameter uncertainties are included through limitation of the PID parameter space. This parameter space is calculated by the parameter space approach and serves as the basis of the presented tuning methods. Hence, all tuning methods guarantee robust stability.

Satellite- and Map-based Long Range Cooperative Adaptive Cruise Control System for Road Vehicles

Abstract Accompanying the introduction of the European navigation satellite system “Galileo”, possibilities of Global Navigation Satellite System (GNSS) for advanced applications in the field of driver assistance systems are currently discussed. A possible application is the extension of Adaptive Cruise Control (ACC) systems for road vehicles for situations where the vehicles cannot locate each other using on-board sensors. This can for example be driving through tight corners and on hilly roads, where radar- or lidar-based sensors reach their geometric limitations as well as situations where vehicles located far ahead have to be accounted for (e.g. at the end of a traffic jam). This paper presents a novel extension of an ACC system to a GNSS- and map-based Cooperative Adaptive Cruise Control (CACC) system for road vehicles. The CACC system implements a distance control based on position data acquired from a GNSS, a digital road map, and vehicle-to-vehicle (V2V) communication. The system is validated in experiments.

An approach for calculating all stable PID parameters for time delay systems with uncertain parameters

Abstract There exists a large number of PID tuning rules for LTI systems. However, these rules often use time delay approximations and ignore parameter uncertainties. This work updates the classical parameter space approach to an one step PID tuning approach to guarantee robust stability for LTI time delay systems with explicit consideration of uncertainties in the plant parameters and the time delay. The basic idea is to calculate how the root boundaries changes due variation of system parameters. Bands of root boundaries are determined by this analysis. The challenging task of robust stability of time delay systems is converted to an easier minimum/maximum search to estimate the borders of the root boundary bands. The presented method satisfies robust stability with only small conservatism.

Safety Verification of a Cooperative Vehicle Platoon with Uncertain Inputs Using Zonotopes

Abstract This paper presents an approach to safety verification of a controlled cooperative platoon of vehicles. To guarantee collision free operation, spacing errors must not exceed critical bounds. Our approach is based on the reachability analysis of linear systems subject to uncertain inputs. The reachable sets are represented by zonotopes. We propose an accurate approximation of the contribution of the uncertain inputs to the whole reachable set. This approach reduces the propagation of the over-approximation error and leads to tight approximation sets.

Longitudinal Vehicle Guidance in Networks with changing Communication Topology

Abstract This paper presents a novel approach to control layout for vehicle guidance with changing communication topology. The control adapts to possible communication failure and varying access to other vehicles information including stability conditions for arbitrary switching between different topologies. On the one hand the control layout addresses deficiencies in vehicle-to-vehicle communication, it further accounts for the reduction of spacing errors and a limitation in velocities and accelerations of following vehicles to avoid saturations. All objectives are formulated as one set of linear matrix inequalities that are solved for each of the adaptive vehicle controls. The optimization is presented for different information topologies of a platoon with four vehicles and the effectiveness of preserving the control performance in case of communication failure is shown through simulations.

Control Design for Generalized Platoon Problems

Abstract This paper presents a generalized description of linear transport processes that allows for a derivation of common dynamic properties and a control layout for a wide set of applications. Based on the introduction of the system description of platoons and a proposition of suitable performance criteria a control layout is formulated which reduces the synchronization of a common motion of sub-systems to a stabilization problem of the platoon and optimizes the corresponding performance measures. Furthermore, the influence of communication topology and switching information access among platoon members is investigated. The proposed approach is applied to a vehicle platoon with one leading and three following vehicles and is analyzed through both simulations and physical experiments with model scale vehicles. The results show that the approach is also applicable to physical plants that can only be approximated by a linear platoon model. Zusammenfassung In diesem Beitrag wird eine verallgemeinerte Beschreibung von Transportprozessen vorgestellt, die eine Ableitung gemeinsamer Systemeigenschaften sowie die Auslegung von Regelungen für eine Vielzahl von Prozessen ermöglicht. Auf Basis der eingeführten Systembeschreibung von Kolonnen und der Formulierung geeigneter Gütekriterien wird ein Reglerentwurf vorgeschlagen, der die Synchronisierung einer gemeinsamen Bewegung aller Teilsysteme auf die Stabilixsierung der Kolonne zurückführt und eine optimale Lösung in Bezug auf die formulierten Güteanforderungen darstellt. Des Weiteren wird der Einfluss der Kommunikationstopologie und der schaltenden Änderung von Informationsverfügbarkeit innerhalb der Kolonne untersucht. Der vorgeschlagene Entwurf wird auf das Beispiel einer Fahrzeugkolonne mit einem Führungsfahrzeug und drei Folgefahrzeugen angewendet und durch Simulationen sowie durch Experimente an Modellfahrzeugen analysiert. Die Ergebnisse zeigen, dass sich das Verfahren auch auf physikalische Strecken, deren Dynamik lediglich durch lineare Modelle approximiert werden kann, anwenden lässt.

Object-oriented Model Library of the Cardiovascular System Including Physiological Control Loops

“HumanLib” is an object-oriented component library for modeling and simulation of the human cardiovascular system including physiological control loops. Possible fields of application comprise analysis of physiological processes, development and testing of assist devices (e.g. TAH, VAD) and education and training. A graphical user interface encapsulates the most important clinical parameters, thus providing an easy-to-use interface to the more complex model.

Konzept zur Sollwertgenerierung und Modellgestützten Prädiktiven Regelung für die Querführung von Nutzfahrzeugkonvois (Concept for the Generation of Reference Variables and Model-Based Predictive Control for the Lateral Guidance of Heavy-Duty Vehicle Platoons)

Das Konvoifahren von Nutzfahrzeugen stellt eine mögliche Organisationsform für den zukünftigen Güterkraftverkehr dar. Während das Führungsfahrzeug manuell gesteuert wird, werden alle Folgefahrzeuge automatisch längs- und quergeführt. In diesem Beitrag wird ein Konzept zur Sollwertgenerierung sowie zur Modellgestützten Prädiktiven Regelung (MPR) für die im Rahmen der Bahnführung notwendige Querregelung vorgestellt. Das Regelungsverfahren wird in Simulationen unter Berücksichtigung von Parameterschwankungen erprobt und die Ergebnisse werden dargestellt. Heavy-duty vehicle platoons are a possible future form of organisation for goods traffic. Only the leading vehicle is manually driven while all following vehicles are automatically controlled in longitudinal and lateral direction. This paper presents a concept for the generation of reference variables as well as for a model-based predictive control (MPC) to be used for the lateral control within the path tracking. The control method is investigated also considering parameter variations in simulations and the results are presented.

Improvement of Practical Orientation in Teaching by Introduction of an Innovative Laboratory and Competition

Abstract In this paper, an innovative concept for a laboratory and a student competition for the improvement of practical orientation of control engineering teaching are presented. The overall goals of the new teaching concepts are to consolidate the students control theory knowledge, to establish practical relevance of the lectures, to gain experience and to develop creativity as well as team-working skills. A laboratory is planned as an introduction to automatic control for students with no engineering background. The goal is to give the students a practical and basic overview of control theory. In addition, a student contest is introduced, which is focused on autonomous vehicle control problems such as path following and advanced cruise control.