Erik Hedin

Bio: Erik Hedin is an academic researcher from SP Technical Research Institute of Sweden. The author has contributed to research in topics: Communications system & Platoon. The author has an hindex of 2, co-authored 2 publications receiving 160 citations.

Field Measurements of IEEE 802.11p Communication in NLOS Environments for a Platooning Application

Abstract: This paper presents results from field measurements on a vehicle-to-vehicle communication system based on IEEE 802.11p. During the measurements the vehicles were moving and there were also moving obstacles located between the transmitting and receiving nodes creating a Non-Line-of-Sight environment. Distance, speed and type of obstacles were varied during the measurements. Both a highway and suburban environment was tested. The tests were focused on packet error rate and consecutive packet loss. The results of the measurements are compared with the communication requirements of a vehicle platooning application which is a novel intelligent transport system application. It implies multiple vehicles tightly following each other in a row. Performance of the application degrades with consecutive packet loss. It is shown that the platooning application is not adequately supported in all measurement scenarios.

Distributed Consensus Strategy for Platooning of Vehicles in the Presence of Time-Varying Heterogeneous Communication Delays

Abstract: We analyze and solve the platooning problem by treating it as the problem of achieving consensus in a network of dynamical systems affected by time-varying heterogeneous delays due to wireless communication among vehicles Specifically, a platoon is modeled as a dynamical network where: 1) each vehicle, with its own dynamics, is a node; 2) the presence of communication links between neighboring vehicles is represented by edges; and 3) the structure of the intervehicle communication is encoded in the network topology A distributed control protocol, which acts on every vehicle in the platoon, is derived It is composed of two terms: a local action depending on the state variables of the vehicle itself (measured onboard) and an action depending on the information received from neighboring vehicles through the communication network The stability of the platoon is proven by using Lyapunov–Razumikhin theorem Numerical results are included to confirm and illustrate the theoretical derivation

Overview of platooning systems

Abstract: This paper presents an overview of current projects that deal with vehicle platooning The platooning concept can be defined as a collection of vehicles that travel together, actively coordinated in formation Some expected advantages of platooning include increased fuel and traffic efficiency, safety and driver comfort There are many variations of the details of the concept such as: the goals of platooning, how it is implemented, mix of vehicles, the requirements on infrastructure, what is automated (longitudinal and lateral control) and to what level The following projects are presented: SARTRE – a European platooning project; PATH – a California traffic automation program that includes platooning; GCDC – a cooperative driving initiative, SCANIA platooning and; Energy ITS – a Japanese truck platooning project

Current Challenges for Visible Light Communications Usage in Vehicle Applications: A Survey

Abstract: In the context of an increasing interest toward reducing the number of traffic accidents and of associated victims, communication-based vehicle safety applications have emerged as one of the best solutions to enhance road safety. In this area, visible light communications (VLC) have a great potential for applications due to their relatively simple design for basic functioning, efficiency, and large geographical distribution. This paper addresses the issues related to the VLC usage in vehicular communication applications, being the first extensive survey dedicated to this topic. Although VLC has been the focus of an intensive research during the last few years, the technology is still in its infancy and requires continuous efforts to overcome the current challenges, especially in outdoor applications, such as the automotive communications. This paper is aimed at providing an overview of several research directions that could transform VLC into a reliable component of the transportation infrastructure. The main challenges are identified and the status of the accomplishments in each direction is presented, helping one to understand what has been done, where the technology stands and what is still missing. The challenges for VLC usage in vehicle applications addressed by this survey are: 1) increasing the robustness to noise; 2) increasing the communication range; 3) enhancing mobility; 4) performing distance measurements and visible light positioning; 5) increasing data rate; 6) developing parallel VLC; and 7) developing heterogeneous dedicated short range communications and VLC networks. Addressing and solving these challenges lead to the perspective of fully demonstrating the high potential of VLC, and therefore, to enable the VLC usage in road safety applications. This paper also proposes several future research directions for the automotive VLC applications and offers a brief review on the associated standardization activities.

An Adaptive Switched Control Approach to Heterogeneous Platooning With Intervehicle Communication Losses

Abstract: The advances in distributed intervehicle communication networks have stimulated a fruitful line of research in cooperative adaptive cruise control (CACC). In CACC, individual vehicles, grouped into platoons, must automatically adjust their own speed using on-board sensors and communication with the preceding vehicle so as to maintain a safe intervehicle distance. However, a crucial limitation of the state of the art of this control scheme is that the string stability of the platoon can be proven only when the vehicles in the platoon have identical driveline dynamics and perfect engine performance (homogeneous platoon), and possibly an ideal communication channel. This paper proposes a novel CACC strategy that overcomes the homogeneity assumption and that is able to adapt its action and achieve string stability even for uncertain heterogeneous platoons. Furthermore, in order to handle the inevitable communication losses, we formulate an extended average dwell-time framework and design an adaptive switched control strategy, which activates an augmented CACC or an augmented adaptive cruise control strategy depending on communication reliability. Stability is proven analytically and simulations are conducted to validate the theoretical analysis.

A Consensus-Based Approach for Platooning with Intervehicular Communications and Its Validation in Realistic Scenarios

Abstract: Automated and coordinated vehicles' driving (platooning) is very challenging due to the multibody control complexity and the presence of unreliable time-varying wireless intervehicular communication (IVC). We propose a novel controller for vehicle platooning based on consensus and analytically demonstrate its stability and dynamic properties. Traditional approaches assume the logical control topology as a constraint fixed a priori , and the control law is designed consequently; our approach makes the control topology a design parameter that can be exploited to reconfigure the controller, depending on the needs and characteristics of the scenario. Furthermore, the controller automatically compensates outdated information caused by network losses and delays. The controller is implemented in Plexe , which is a state-of-the-art IVC and mobility simulator that includes basic building blocks for platooning. Analysis and simulations show the controller robustness and performance in several scenarios, including realistic propagation conditions with interference caused by other vehicles. We compare our approach against a controller taken from the literature, which is generally considered among the most performing ones. Finally, we test the proposed controller by implementing the real dynamics (engine, transmission, braking systems, etc.) of heterogeneous vehicles in Plexe and verifying that platoons remain stable and safe, regardless of real-life impairments that cannot be modeled in the analytic solution. The results show the ability of the proposed approach to maintain a stable string of realistic vehicles with different control-communication topologies, even in the presence of strong interference, delays, and fading conditions, providing higher comfort and safety for platoon drivers.