François Guerin

Hybrid Modeling for Performance Evaluation of Multisource Renewable Energy Systems

This paper is devoted to multisource renewable energy systems. A modeling approach is proposed that brings a detailed understanding of the coupling and uncoupling of DC/DC power converters on a DC bus including the regulation of the DC bus voltage and the driving of current provided by each converter to the load. This approach is systematic and the resulting average state-space model depends only on the number and characteristics of the converters. The model has a generic expression the parameters of which switch according to the converters coupling and uncoupling on the DC bus. The model has been identified and validated with an experimental device developed by GREAH Research Group for the optimization of energies transfers for multisource renewable energy systems. Our approach can be used in the context of power management as support for performance evaluation (converter design, supervisory control design, and so on).

Multimodel for the coupling of several dc/dc power converters on a dc bus

This paper concerns multisource renewable energy systems. It describes the design of an average state space model that brings a detailed physical explanation of the coupling and uncoupling of several dc/dc power converters on a dc bus. A multimodel is proposed for that purpose, which consists in a mathematical generic expression whose parameters change according to the dc/dc power converters coupled on the dc bus. This multimodel can be used as support for the design of hybrid control laws in order to optimize the energies transfers, according to the sources power variations and the load characteristics. It takes into account conduction losses in dc/dc power converters and makes it possible to evaluate the efficiency of the equipment.

UAV-UGV cooperation for objects transportation in an industrial area

We present in this paper a decentralized multirobot (aerial and ground) cooperation scheme for objects transportation. A team of ground mobile robots guided by a drone and a human operator moves in a coordinated way keeping a predefined formation in order to carry objects (tools, gas masks,...) in unsafe industrial areas. One ground mobile robot (leader) navigates among obstacles thanks to the waypoints provided by the drone and the human operator. The other ground mobile robots (followers) use a predictive vision based target tracking controller to keep a certain distance and bearing to the leader.

Double Exponential Smoothing for predictive vision based target tracking of a wheeled mobile robot

This paper describes the design of a novel nonlinear kinematic controller which allows a wheeled mobile robot to track a moving target at a given separation distance. The Double Exponential Smoothing algorithm is employed to deal with uncertainties in the measurements and to acquire a predictive estimate for the robots relative position. This estimate is used to automatically adjust the proportional gain of the controller in order to regulate the tracking error.

Petri nets control design for hybrid electrical energy systems

This paper describes a supervisory control strategy based on Petri nets for electrical energy transfers in multisource renewable energy systems. The aim is to optimize the energy transfers, according to the sources power variations and the load characteristics. For this purpose, the proposed Petri net controller calculates the operating mode of the multisource renewable energy system. This high level controller is combined with a low level one that tunes the power ratio provided by each source according to sources power (climatic conditions) and load variations. An estimation of the duty cycle value of the dc/dc power converters is used to fire the Petri nets transitions, to switch the power sources and also to drive the power ratios.

A decentralized interactive architecture for aerial and ground mobile robots cooperation

This paper presents a novel decentralized interactive architecture for aerial and ground mobile robots cooperation. The aerial mobile robot is used to provide a global coverage during an area inspection, while the ground mobile robot is used to provide a local coverage of ground features. We include a human-in-the-loop to provide waypoints for the ground mobile robot to progress safely in the inspected area. The aerial mobile robot follows continuously the ground mobile robot in order to always keep it in its coverage view.

Vision based target tracking using an unmanned aerial vehicle

We present in this paper a backstepping controller for vision based target tracking with an Unmanned Aerial Vehicle. A down facing camera is used with a pose estimation algorithm to extract the position of the target (an Unmanned Ground Vehicle). The output is then fed into the developed controller to generate the necessary movements (pitch and roll) of the Unmanned Aerial Vehicle in order to keep the target in the coverage view of the camera (following it constantly). The developed scheme is used to help the Unmanned Ground Vehicle to navigate among obstacles, and the overall system is designed in order to help human operator to supervise the Aerial and Ground vehicles for area inspection or object transportation in industrial areas (when using multiple Unmanned Ground Vehicles).

About detection and diagnosis of Freezing of Gait

This paper is about the initiative of detecting Freezing of Gait (FoG) in Parkinson Disease (PD). Summarizing more than twelve years of accumulated data, presenting the techniques used, and evaluating their results would create a reference paper for future works. We traced the development of diverse researches and sensor-based systems (acceleration, force resistive, angle, EMG, etc...) to expand and refine the results, pointing out flaws and demonstrating the advantages of each one. The paper sums up the investigations in one of the most unpredictable and impairing symptoms of PD, specifically the area of FoG detection and prevention.

Control design for multisource systems based on DC/DC converters duty cycle value

Purpose – The purpose of this paper is to describe a two‐level hierarchical control strategy for electrical energy transfers in multisource renewable energy systems. The aim of the control design is to perform the energy transfers, according to the sources power variations and the load characteristics.Design/methodology/approach – The controller determines the operating mode of the multisource renewable energy system and the power ratio provided by each source to satisfy the load demand. The study is based on an accurate model of the DC/DC converters coupled on the DC bus. The performance of the controller is compared with the usual method based on the measurements of the system variables with sensors (solar radiation, shaft speed, voltages, and currents).Findings – The proposed method does not need extra sensors to measure the available power for each source.Research limitations/implications – The method is developed for an hybrid system with two sources (photovoltaic and lead‐acid battery bank) and spec...

Fuzzy logic controller for predictive vision-based target tracking with an unmanned aerial vehicle

Abstract We present in this paper a Fuzzy Logic Controller (FLC) combined with a predictive algorithm to track an Unmanned Ground Vehicle (UGV), using an Unmanned Aerial Vehicle (UAV). The UAV is equipped with a down facing camera. The video flow is sent continuously to a ground station to be processed in order to extract the location of the UGV and send the commands back to the UAV to follow autonomously the UGV. To emulate an experienced UAVs pilot, we propose a fuzzy-logic set of rules. Double Exponential Smoothing algorithm is used to filter the measurements and give the predictive value of the errors in the image plan. The FLC inputs are the filtered errors (UGV position) in the image plan and the derivative of its predicted value. The outputs are pitch and roll commands to be sent to the UAV. We show the efficiency of the proposed controller experimentally, and discuss the improvement of the tracking results compared to our previous work. Graphical Abstract