He was with the IBISC Lab at UEVE, working on the control of haptic display under varying time delay in the frame of his Ph.D. dissertation. Since 2003, he has been an Associate Professor of electrical engineering with UEVE. His research interests include control of force feedback systems and driving simulator applications (Motorcycle and Four-Wheeled vehicles).
Abstract: Driving simulators are more and more used for driver evaluation and/or education. In this paper, we describe the design and the modeling aspects of a 2 DOF low cost motion platform allowing the rendering of the longitudinal and yaw movements. This prototype will be used to study various configurations of motion rendering and the impact of these variants on controllability and on simulator sickness. The whole motion platform is considered as two coupled systems that are linked mechanically. The first system consists of a motorized rail for the longitudinal movement which is mounted on top of the second system, a motorized turret allowing to rotate the platform. We present the platform mechanics and a number of experimental studies that have been carried out to obtain a characterization of the platform capabilities and frequency responses as well as to assess platform performance in a classical drive operation. First conclusions and directions of future work are presented.
Abstract: This paper describes a new motorcycle riding simulator whose purpose is twofold: (1) it can be used as a training tool for new riders in different scenarios, such as a normal traffic environments or in dangerous riding situations (avoidance, emergency braking, nearly failing or slipping situations and bad weather conditions); and (2) it can be used to study cyclist behavior in such situations and rider-motorcycle interaction.
Our studies have led to the development of an original five degrees-of-freedom (DOF) mechanical platform including double haptic feedback on the handlebar. The remaining components are the basic movements consisting of pitch, roll, and yaw. These components are gathered in a parallel kinematics-type platform to enhance the movement bandwidth of the two-wheeled riding simulator.
Despite its simplicity, the particular appeal of this simulator lies in the possibility of reproducing important motorcycle movements and inertial effects which allow for the perception of sensations close to reality. The motivation behind the choice of platform movements and system actuation are described. Also, theoretical issues (modeling, identification and control aspects) and performance results are provided.
Abstract: This paper presents a driving simulation whose aim is twofold: (1) to investigate the possibility of reducing motion clearance to achieve compact and low-cost driving simulators and (2) to evaluate multimodal and immersive virtual reality motion restitution in platooning driving. The choice has been made for a driving simulator having at least two degrees of freedom (DOF). These consist of the longitudinal displacement and seat rotations. The simulator is also equipped with a force feedback steering wheel for virtual drive assistance. These components are gathered on a serial kinematics-type platform to facilitate a control scheme and avoid the architecture complexity. A comparative study was made to devise a motion cueing strategy, taking into account both the psychophysical and technological constraints. Experimentations were carried out for several case combinations of the longitudinal displacement and seat rotations.
Abstract: This paper addresses the stability of time-delayed force-reflecting displays used in virtual reality interactive systems. A novel predictive-like approach is proposed. The developed solution is stable and robust. Neither time delay estimation nor time delay behavior's knowledge are required. The controller applies to constant or time-varying delays without any adaptation. In this research, efforts are devoted towards making results easy to implement in commercial haptic libraries and interface build-in controllers. Moreover, although this study focuses on virtual environments haptics, it can easily spread to force feedback teleoperators.
Abstract: This chapter contains sections titled:
Introduction
Haptic simulation in VR applications
Delayed force feedback systems
The Quality of Service for a good haptic rendering
Abstract: In this paper, we consider a bilateral control of an assistive mobile robot over communication channels with constant/variable time delays. The mobile robot is used for exploring a domestic environment. The main purpose of the present work is to help the human in controlling better the slave robot. In addition, the proposed control scheme improves the operator perception of the remote environment. The human-operator can actively control the mobile robot, using its intrinsic sensors, and ``feel" the robot's environment. The haptic device is used like a joystick and controls the linear velocity and heading angle of the mobile robot. Many experiments have been performed to validate the proposed control scheme, and to show, in the same time, the importance of the force feedback in such applications and accessibility situations : doorways, obstacle exploration, wall tracking, etc.
Abstract: A direct application of the variable-gain super-twisting algorithm (VGSTA) is implemented for torque feedback on a handlebar of a riding simulator. This control strategy aims to compensate perturbations changing with the system states. Thanks to the good tracking performance and robustness/insensitiveness of such a control method, a precise estimation of the rider's torque applied on the riding simulator handlebar is possible. A first-order sliding-mode observer with stabilization is designed for the estimation of the unknown input rider action. Experimental implementation and analysis are provided to point-out the effectiveness of the proposed approach.
Abstract: This paper is dedicated to the problem of observer design for Takagi-Sugeno (T-S) nonlinear systems with unmeasurable premise variables (TSUPV) and application to autonomous bicycle system. The main idea is based on the use of differential mean value theorem combined to the sector nonlinearity transformation. The objective of this approach is to make the state estimation error dynamic on a T-S form which allows to apply the classical Lyapunov analysis to derive convergence conditions. The design algorithm is proposed in terms of linear matrix inequalities (LMI). To illustrate the proposed methodology, a nonlinear bicycle model is considered.
Abstract: In this paper, we present a review of the existent two-wheeled vehicle simulators. A description of a motorcycle simulator, designed by INRETS-IBISC laboratories, is given. Mechatronics aspects and the various consideration to built such a simulation tool will be discussed.
Abstract: In this paper, we propose an estimation process for rider's torque during drive operation on simulator. The idea is basic and, in one hand, uses a DC motor as torque sensors and, on the other hand, as generator of force feedback due to tire-ground contact. The experimental implementation and analysis have revealed the effectiveness of the proposed approach.
Abstract: In this paper, we present a new method for the computation of the maximal authorized motorcycle speed in curves. The three main factors which are the vehicle, the driver and the infrastructure are taken into account. The vehicle dynamics are represented by a four degrees of freedom model which includes the vehicle's longitudinal slip and sideslip angle. The driver behavior model considers the ability in deceleration maneuvers according to the mobilized friction. The infrastructure characteristics introduce a precise handling of the road geometry and of the maximal available friction.
Abstract: In this paper, the problem of tracking control of nonholonomic mobile robot is investigated using feedback linearizing control. A cascaded control strategy has been designed to control the real mobile robot (kinematic model and robot dynamics), where the inner loop control for dynamics model is based on inverse dynamics and the outer loop control based on dynamic feedback linearizing control is carried out for kinematics model. The closed loop system is fully linearizable and described by a chain of integrators, and an exponentially stabilizing feedback for the desired trajectory can be designed for pole placement. The controller deals with unknown disturbance through a compensator carried out from the dynamics controller. The disturbance compensator contains an integral action, which eliminates the steady errors and enhances the robustness of the control scheme. Simulations are carried out for a nonholonomic mobile robot to verify the performance of the proposed control scheme.
Abstract: This paper deals with modeling, control and identification issues of 2 degrees of freedom (DOF) low cost driving simulator validated by experimental results with a human in the loop. A first study, dealing with choices of the platform's motion, has conducted us to an original architecture allowing the restitution of longitudinal and yaw movements based mechanics. To better immerse the driver in the virtual world and stimulate his perception, a haptic feedback steering wheel is be implemented to assist the human in driving. The present motion platform is designed to help psychophysicists to assess the effects of yaw components on the simulator sickness. Experimental studies were carried out to devise a characterization of the platform capabilities, frequency responses and for classical drive operation. Conclusion and future works are given.
Abstract: In order to be an effective tool for driver evaluation and education, driving simulators need to be better designed to reduce simulator sickness. In this paper, we expose platform design, description and the modeling aspects of a 2 DOF low cost motion platform allowing the restitution of the longitudinal and yaw movements. To enhance the drive immersion in the virtual world, a haptic feedback steering wheel will be implemented. The whole system is considered as a two coupled systems and linked mechanically. The first system consists in motorized rail for the longitudinal movement while the second system consists in motorized yaw allowing either curve-taking movement. The platform mechanics is proposed as presented in the next sections to study the driving simulator sickness on the driver and especially the yaw component. Experimental studies were made to devise a characterization of the platform capabilities and frequency responses. Experimentations were carried out for classical drive operation. First conclusion and future works are established.
Abstract: In this paper, we present a new method for the calculation of the maximum roll angle of a motorcycle authorized during driving in curve situation. The proposed approach takes into account the three elements of the driving situation which are the vehicle the driver and the infrastructure. The vehicle dynamics are represented by a dynamic four degrees of freedom model which include longitudinal and lateral dynamics of the motorcycle. The driver behaviour considers his ability in deceleration taking into account his mobilized friction while the infrastructure characteristics introduce a precise definition of the road geometry and the maximal available friction.
Abstract: This paper describes a modelling technique for deriving the motorcycles equation of motion. Based on the recursive Newton-Euler approach adapted to tree structure with floating base multibody systems, the derived model presents a low number of arithmetic operations, and hence, is suitable for implementation into a two wheeled vehicles simulator and other model based real-time application. The synthesized model takes in consideration the main forces and moments affecting the behavior of the motorcycle such as: pneumatic, aerodynamic, suspensions, contact constraints and control inputs.
Abstract: This paper presents the dynamics modeling and parameters identification of a motorcycle simulator's platform. This model begins with some suppositions which consider that the leg dynamics can be neglected with respect to the mobile platform one. The objectif is to synthesis a simplified control scheme, adapted to driving simulation application, minimising dealys and without loss of tracking performance.
Electronic system of platform actuation is described. It's based on a CAN BUS communication which offers a large transmission robustness and error handling. Despite some disadvanteges, we adapted a control solution which overcome these inconvenients and preserve the quality of tracking trajectory.
A bref description of the simulator's platform is given and results are shown and justified according to our specifications.
Abstract: This paper describes a modelling technique for deriving the motorcycles equation of motion. Based on the recursive Newton-Euler approach adapted to tree structure with floating base multibody systems, the derived model presents a low number of arithmetic operations, and hence, is suitable for implementation into a two wheeled vehicles simulator and other model based real-time application. The synthesized model takes in consideration the main forces and moments affecting the behavior of the motorcycle such as: pneumatic, aerodynamic, suspensions, contact constraints and control inputs.
Abstract: In this paper, we present a modeling technique for deriving the motorcycles equation of motion. The proposed technique is based on the recursive Newton-Euler approach and adapted to tree structure with floating base multibody systems. The derived model presents a low number of arithmetic operations, and hence, suitable for implementation into a two wheeled vehicles real-time applications such as driving simulators. The synthesized model takes in consideration the main wrenches that affect the behavior of motorcycle such as: pneumatic, aerodynamic, suspensions, contact constraints and control inputs.
Abstract: Nonlinear predictive controller for induction motor drive is presented. The load torque, considered as an unknown disturbance, is compensated using a disturbance observer. First, a nonlinear multivariable predictive controller is applied to track the torque and rotor flux norm trajectories. Then, a speed predictive control strategy is carried out from the electromechanical equation of the machine. Both controllers are applied in a cascade structure to induction motor. The prediction model is carried out via Taylor series expansion using Lie derivatives for nonlinear model. The derived predictive law minimizes a quadratic performance index of the predicted tracking error for multivariable system and a predicted error for speed control. The implementation of the cascaded control law does not need an on line optimization and the tracking of desired trajectories is achieved successfully. The load torque observer, derived from the speed predictive control, is simplified to a PI structure. This observer structure guarantees the disturbance rejection and the robustness to parameters variations. Simulation results show the high performance of the proposed control scheme.
Abstract: This paper presents the various stages for the construction of a two wheeled riding simulator. Despite its simplicity, the particularity of this simulator comes from the possibility to reproduce most of the movements and the inertial effects allowing to perceive sensations close to reality cases. This simulator has been developed for two purposes: ldr as a training tool for new riders with different scenarios: normal traffic environment, dangerous riding situations (avoidance, emergency braking, nearly failling or slipping situations, bad weather conditions, etc.) ldr to study riders behaviours in such situations Our studies have lead to an original 5 degrees of freedom (DOF) mechanical platform including a double haptic feedback on the handlebar. The three basic movements are classical and consist of pitch, roll and yaw one. The choices of the platform movements and the system actuation are motivated and described. Also, some performances results are shown validating the initial requirements.
Abstract: This paper presents the development of motorcycle dynamics model. The considered vehicle contains six bodies linked with simple joints and parametrised by 11 degrees of freedom (DOF). The motorcycle model is to be used as a component in driving simulator application. It serves to investigate the influence of using a complete motorcycle dynamics model in inertial cues realism. The choice of the modeling method is based on the algorithmic Lagrange equation representation. This method makes the implementation of the dynamic model very easy. In addition, the principal external forces affecting the motorcycle behavior are considered (pneumatic forces, driver actions, brakes ... etc). At the end of this article, some simulation results are presented in the case of street line motion.
Abstract: This paper deals with motion control problem for a 2 DOF small
driving simulator. The main idea is to test and compare performances of
different Washout Algorithms applied to such platform category.
Abstract: This paper deals with motion control problem for a 2 DOF small driving simulator. The main idea is to test and compare performances of different Washout algorithms applied to such platform category. The experimentations allow us to have the best compromise between quality of the human perception, implementation complexity and platform architecture type. Implementation of different washout algorithms (optimal, adaptive and classical one) are discussed. For an objective comparison, the classic algorithm was synthesized so as to take into account the human perception thresholds and the platform workspace limitations. A modelling of a second DOF (seat tilting) is given and simulated to show the inertial effect of the seat movement. Finally, psychophysics study, experimental results and conclusion are given.
Abstract: This paper deals with the problem of transparency (or fidelity) in force feedback systems or more particularly for haptics simulation under time delay transmission. The haptics rendering transparency is all the more difficult in distributed collaboration between distant users because it is necessary also to make feel faithfully the mutual interactions. The idea suggested in this article gives an original solution to overcome this lack of transparency in haptic shared collaborations on the network using a principle called the "Latency Envelope" (LE). One advantage of this implementation is the anticipation of the contact between users and virtual objects. The delay can them be partially or completely compensated from the operator perception point of view. Also it does not affect at all the stability of haptics simulation (carried out using well known control laws).
Abstract: The paper deals with control of small driving simulator SIM comparing the useless of adaptive and classic approaches. Driving simulators are considering as an interactive virtual reality tools, which take a considerable place in the human factors studies. The difficulty to reproduce in reality some drive situations mainly for risk and reproducibility reasons increases the interest of this tool. Nevertheless, the validation of the experiments carried out on driving simulator is closely related to embedding realism of the driver in the simulated world. In this article, we present the design of a low cost and small motion platform, which allow the restitution of 2 DOF movements. This overall system is considered as two independent systems linked mechanically. The first system consists in motorized rail for the longitudinal movement while the second system consists in motorized seat allowing either pitch movement of this one or just back seat inclination (this case would not be discussed in the rest of paper)
Abstract: In this paper a controller derived from Smith pre- dictor for non-varying time
delayed force re‡ect- ing interaction devices is presented. A feedback law
which compensates the time delay by its elim- ination from the
Abstract: This paper extends earlier results of wave based ap- proach for stable force reflecting systems in the pres- ence of the transmission delay (constant or variable). Theoretically, stability of the whole system is kept for any
Abstract: A modified Smith predictor for linear delayed haptic interaction is presented. The objective is to design a feedback law which compensates the time delay by its somehow elimination from the characteristic equation of the closed loop system. This method is robust within a certain safe prediction interval. The applicability of Smith predictor in the case of haptic interaction using computer haptic algorithms is shown.
Abstract: This paper extends earlier results on stable haptic and force feedback interaction in the presence of constant and varying time-delay. Although the paper focuses on virtual environment (VE) based haptics, results can also apply to teleoperation. The proposed method considers extending our preliminary work where Smith prediction principle has been adapted on delayed haptic feedback interaction. We shall show that this proposed approach is easy to implement and is original since it investigates another way to formulate stable haptic feedback algorithms. It requires to know only the model of the master interface or the haptic display. Stability and robustness analysis are thoroughly discussed. Experimental results and comparison with wave variables are discussed.
Abstract: Readership: Undergraduate and postgraduate students in: Electrical engineering, Electronics engineering and Mechanical engineering; Robotics researchers; Mechatronics researchers; Robotics companies; Transportation companies; Process engineering users.
All papers have been peer-reviewed. The "Intelligent Systems and Automation" conference will be organized for its first edition between June 30 and July 02, 2008, where it will be held at Annaba, in Algeria (Africa). CISA encourages the diverse research actors and industrialists to present the last headways in "Robotics and Automation" fields, notably the experimental demonstration of prototypes. CISA tries to give to the unsupported researchers significant access to the new technologies and theories surrounding the topics of Robotics & Automation. The organizers want to give the necessary scientific documents to disposal of the PhD students and researchers of the Mediterranean region. CISA aims to offer to the youth researchers from the south Mediterranean region the opportunities to exchange and to discuss their scientific contributions with the other researchers from all over the World.
