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In automotive control, torque vectoring enhances a vehicle dynamical characteristic by independently allocating wheel torques. Torque vectoring algorithms are often based on some form of closed-loop yaw rate tracking, whose reference is generated according to the driver's steering input. Thus, unless the vehicle is equipped with steer-by-wire, from the torque vectoring point of view, the driver's input simultaneously acts as a reference and as a disturbance. This paper presents a method to explicitly consider this aspect in the torque vectoring design by means of a feedforward compensation. At first, we identify the plant model highlighting the effects of the driver input steer on the system. Then, we design the compensation term with H∞techniques based on the identified model. This solution is then refined using a Data-Driven approach based on a Bayesian optimization algorithm. Results show that the compensation term can reduce the tracking error by 40% and the control effort by 35%.

This paper presents a realtime recursive algorithm that can estimate, starting from an unknown pose, the mounting angles (roll, pitch and yaw) of an inertial sensor unit using accelerations and angular velocities. We analyze the use case of telematic boxes (E-Box) that are mounted on ground vehicles for safety reason (like E-call or automatic crash detection) or driving style monitoring. In order to work properly and record meaningful data, the box reference frame needs to be correctly aligned with the vehicle one. The proposed algorithm aligns the two reference frame online while the car is running throughout a series of filters and data point selection logics. Results show that the algorithm is robust with respect to any box mounting position or vehicle, with, on average, a convergence time of less than 20 minutes to the correct angles.

This work investigates the use of Active Aerodynamic Surfaces (AAS) to enhance ride comfort in sport vehicles. Four AAS's generate lift forces that control the vertical acceleration of the sprung mass without negatively affecting the unsprung mass. It is shown that the AAS system can overcome the trade-off between comfort and road holding. In this work a preliminary analysis of the control system is presented along with a mechatronic feasibility analysis. The required controller bandwidth, airfoils size and power requirements are analyzed in simulation. The system is validated on a complete vehicle model showing improvements of the order of 30% in ride comfort with no negative effects on road-holding at high speed.

Electrically Power Assisted Cycles (EPACs) have been gaining increasing attention worldwide during the past few years. The delivery of a good assistance during inclines makes or destroys an EPAC. This paper addresses the low-cost estimation of road slope on bicycle without pedaling torque measurement. Two estimation algorithms are discussed. A full 6 Degrees of Freedom kinematic Extended Kalman Filter and a simpler, more cost-effective 2 DoF Kalman filter based on the longitudinal kinematic model. The proposed reduced-sensor algorithm is shown to be very accurate during straight running; however it is affected by errors during cornering. This issue is addressed by augmenting the filter with a curve correction algorithm. The curve correction algorithm, based on a time-varying low pass filter is detailed and validated on experimental data, comparing the estimated road slope against cartographic data.

This work addresses the design of a heart rate (HR) control system for a bicycle equipped with a continuously varying transmission. The control system helps the cyclist maintain a constant physical effort throughout the trip. The bicycle longitudinal dynamics and a control-oriented model of the cyclist's HR dynamics are the basis for the development of a controller. The HR dynamics is subject to considerable uncertainties due to inter subject differences, nonlinearities and other factors that are not directly influenced by the cycling physical effort. In the control system design phase, these are addressed by designing a second order sliding mode controller. The controller is experimentally validated on several subjects comparing the HR with the without the CVT control, showing that the HR is maintained within 10 BPM from the desired one.

In this paper a robust road departure avoidance system based on a closed-loop driver decision estimator (DDE) is presented. The goal is that of incorporating the driver intent in the control of the vehicle. The proposed system ensures that the vehicle remains within the road borders with minimal effect on the driver demand. Numerical simulations show the effectiveness and robustness of the proposed approach. A comparison between the presented method and the generalization of methods available in the literature is presented.

In four-wheeled vehicles, electronic stability control (ESC) was introduced in the recent past to improve passengers’ safety in critical driving conditions and it is now part of most commercial cars. For two-wheeled vehicles, the design of such a control system is an open problem, and it constitutes quite a challenging task due to the complexity of two-wheeled vehicles dynamics and to the strong interaction between the vehicle and the driver. This paper describes an innovative control architecture which allows us to enhance the active safety while guaranteeing a good driving feeling. The proposed solutions are validated on a multibody motorcycle simulator on challenging maneuvers such as kick-back and strong braking while cornering at high speed.

This paper addresses the servo-controller design of an electronic throttle body (ETB) designed for ride-by-wire applications in racing motorcycles. The dynamics of the system is identified and a model of the friction is derived from experimental data. It is shown how, by identifying the friction characteristic, it is possible to separately design a linear time invariant closed loop controller and a friction compensator. In the second part of the paper the friction compensator is made adaptive so to enable an automatic and online identification of the friction. Experimental tests validate the controller and compensator design.

This work presents the design of a novel control approach for a semi-active steering damper of motorcycles. The goal is to improve two-wheeled vehicles steering stability by damping the weave and wobble modes. The proposed control strategies stem from a parallelism between steering and vertical dynamics of a motorcycle. According to this parallelism, the Sky-Hook and Ground-Hook damping concepts are adapted to the control of steering dynamics. A detailed analysis of the two approaches is presented and the semi-active control strategies are shown to yield better attenuation of both modes than a passive steering damper. Further, both a multi-body simulator and experimental data are employed to validate the proposed control approach.

In this work a dynamic analysis for the air-gas path of a balanced draft boiler is presented. As is well known, in this part of the plant large and rapid pressure variations can arise in particular situations (for instance in case of fuel trip) which can cause damage to mechanical structures. To achieve a basis of evaluation of these phenomena, a mathematical model of the air-gas system has been developped; the system has been divided into subsystems (fans, air and gas ducts, furnace, air preheaters, dampers) and for each of them a first principles mathematical model has been written. The submodels have then been coupled together to obtain the description of the whole system. This task has been accomplished automatically by means of a suitable “computer aided modelling” code, described in detail in (Marcocci and Spelta, Owing to this modular approach, a wide range of possible plant configurations can be represented. This paper first describes the models of the principal subsystems and the criteria which have been followed to represent with acceptable accuracy the main phenomena involved; a practical application to the air gas path of a real power plant in then presented, and the results obtained in the most critical situations are discussed, with particular attention to operating strategies and control system evaluation.