A novel frequency dependent model based on trigonometric functions for a magnetorheological damper

In this paper, a novel frequency dependent MR damper model based on trigonometric functions is proposed. The model presents the following advantages in comparison with other previously proposed models: (1) it is based on algebraic functions instead of differential equations, so that it does not present convergence problems when noisy inputs from experimental measurements are used; (2) the number of parameters is reasonable, so that it makes the model computationally efficient in the context of parameter identification and (3) the model has to take into account the variation of the parameters as a function, not only of the applied current but also of the frequency of excitation. Experimental results confirm that the proposed frequency dependent MR damper model improves the accuracy of the model in force simulation.Funds provided by the Spanish Government through the CICYT Projects TRA2008-05373/AUT and TRA2011-28548-C02-0

A Novel Inverse Dynamic Model for a Magnetorheological Damper based on Network Inversion

Semi-active suspensions based on magnetorheological (MR) dampers are receiving significant attention specially for control of vibration isolation systems. The nonlinear hysteretic behaviour of MR dampers can cause serious problems in controlled systems such as instability and loss of robustness. Most of the developed controllers determine the desired damping forces which should be produced by the MR damper. Nevertheless, the MR damper behaviour can only be controlled in terms of the applied current (or voltage). In addition to this, it is necessary to develop an adequate inverse dynamic model in order to calculate the command current (or voltage) for the MR damper to generate the desired forces as close as possible to the optimal ones. Due to MR dampers are highly nonlinear devices, the inverse dynamics model is difficult to obtain. In this paper, a novel inverse MR damper model based on a network inversion to estimate the necessary current (or voltage) such as the desired force is exerted by the MR damper is presented. The proposed inverse model is validated carrying out experimental tests. In addition, a comparison of simulated tests with other damper controllers is also presented. Results show the effectiveness of the network inversion for inverse modeling of an MR damper, so that the proposed inverse model can act as a damper controller to generate the command current (or voltage) to track the desired damping force.This work was supported by the funds provided by the Spanish Government through the CICYT projects TRA2008-05373/AUT and TRA2011-28548-C02-01.Publicad

A robust observer based on energy-to-peak filtering in combination withneural networks for parameter varying systems and its application to vehicleroll angle estimation

This paper presents a robust observer based on energy-to-peak filtering in combination with a neural network for vehicle roll angle estimation. Energy-to-peak filtering estimates the minimised error for any bounded energydisturbance. The neural network acts as a 'pseudo-sensor' to estimate a vehicle 'pseudo-roll angle', which is used as the input for the energy-to-peak-based observer. The advantages of the proposed observer are as follows. 1) Itdoes not require GPS information to be utilised in various environments. 2) It uses information obtained from sensors that are installed in current vehicles, such as accelerometers and rate sensors. 3) It reduces computationtime by avoiding the calculation of observer gain at each time sample and utilising a simplified vehicle model. 4) It considers the uncertainties in parameters of the vehicle model. 5) It reduces the effect of disturbances. Bothsimulation and experimental results demonstrate the effectiveness of the proposed observer.This work is supported by the Spanish Government through the Project TRA2013-48030-C2-1-R, which is gratefully acknowledged

Vehicle sideslip angle measurement based on sensor data fusion using an integrated ANFIS and an Unscented Kalman Filter algorithm

Most existing ESC (Electronic Stability Control) systems rely on the measurement of both yaw rate and sideslip angle. However, one of the main issues is that the sideslip angle cannot be measured directly because the sensors are too expensive. For this reason, sideslip angle estimation has been widely discussed in the relevant literature. The modeling of sideslip angle is complex due to the non-linear dynamics of the vehicle. In this paper, we propose a novel observer based on ANFIS, combined with Kalman Filters in order to estimate the sideslip angle, which in turn is used to control the vehicle dynamics and improve its behavior. For this reason, low-cost sensor measurements which are integrated into the actual vehicle and executed in real time have to be used. The ANFIS system estimates a "pseudo-sideslip angle" through parameters which are easily measured, using sensors equipped in actual vehicles (inertial sensors and steering wheel sensors); this value is introduced in UKF in order to filter noise and to minimize the variance of the estimation mean square error. The estimator has been validated by comparing the observed proposal with the values provided by the CARSIM model, which is a piece of experimentally validated software. The advantage of this estimation is the modeling of the non-linear dynamics of the vehicle, by means of signals which are directly measured from vehicle sensors. The results show the effectiveness of the proposed ANFIS+UKF-based sideslip angle estimator

LMI-based H∞ controller of vehicle roll stability control systems with input and output delays

This article belongs to the Section Physical Sensors.Many of the current research works are focused on the development of different control systems for commercial vehicles in order to reduce the incidence of risky driving situations, while also improving stability and comfort. Some works are focused on developing low-cost embedded systems with enough accuracy, reliability, and processing time. Previous research works have analyzed the integration of low-cost sensors in vehicles. These works demonstrated the feasibility of using these systems, although they indicate that this type of low-cost kit could present relevant delays and noise that must be compensated to improve the performance of the device. For this purpose, it is necessary design controllers for systems with input and output delays. The novelty of this work is the development of an LMI-Based H∞ output-feedback controller that takes into account the effect of delays in the network, both on the sensor side and the actuator side, on RSC (Roll Stability Control) systems. The controller is based on an active suspension with input and output delays, where the anti-roll moment is used as a control input and the roll rate as measured data, both with delays. This controller was compared with a controller system with a no-delay consideration that was experiencing similar delays. The comparison was made through simulation tests with a validated vehicle on the TruckSim® software.This work was supported by the FEDER/Ministry of Science and Innovation-Agencia Estatal de Investigacion (AEI) of the Government of Spain through the project [RTI2018-095143-B-C21]

Cloud-Based Collaborative 3D Modeling to Train Engineers for the Industry 4.0

In the present study, Autodesk Fusion 360 software (which includes the A360 environment) is used to train engineering students for the demands of the industry 4.0. Fusion 360 is a tool that unifies product lifecycle management (PLM) applications and 3D-modeling software (PDLM—product design and life management). The main objective of the research is to deepen the students’ perception of the use of a PDLM application and its dependence on three categorical variables: PLM previous knowledge, individual practices and collaborative engineering perception. Therefore, a collaborative graphic simulation of an engineering project is proposed in the engineering graphics subject at the University of La Laguna with 65 engineering undergraduate students. A scale to measure the perception of the use of PDLM is designed, applied and validated. Subsequently, descriptive analyses, contingency graphical analyses and non-parametric analysis of variance are performed. The results indicate a high overall reception of this type of experience and that it helps them understand how professionals work in collaborative environments. It is concluded that it is possible to respond to the demand of the industry needs in future engineers through training programs of collaborative 3D modeling environments

The Importance of the Participatory Dimension in Urban Resilience Improvement Processes

This article discusses the approach adopted by the researchers into citizen participation in urban regeneration actions and projects. It describes the concepts of sustainability and habitability in relation to the urban environment and architecture within the framework of improving the resilience of our cities through the circular economy and decarbonisation processes in architecture. The authors review the participatory dimension of different urban regeneration actions carried out in Spain and the impact of this dimension on the results obtained by environmental, economic and social urban improvements. They then define possible strategies and methodological tools for integrating this dimension into traditional urban regeneration processes. The article presents case studies and their specific characteristics, and draws conclusions about their effectiveness and relevance. It also compares citizen-led interventions with interventions led by public administrations. Lastly, the authors analyse the potential reasons for success in these processes and projects, identifying weaknesses and proposing possible strategies for future development by researchers

Study of van roadworthiness considering their maintenance and periodic inspection. The Spanish case

In Europe, traffic road safety has clearly improved due to many factors. One of them is the improvement of the roadworthiness. However, accidents of vans and light goods vehicles (LGV) have not followed the decreasing tendency of other vehicles. Several studies suggest that vehicle defects are relevant to the cause of accidents. It would be ideal if vehicle owners continuously kept their vehicles in compliance with the roadworthiness standards. Another important aspect to operate with roadworthy vans is the maintenance programs. It is probable that many van owners do not adequately maintain their vehicles or the maintenance programs are not sufficient with the periodic motor vehicle inspections (PMVI) intervals or with the items inspected. This paper analyses the maintenance schedules and PMVI of vans in order to assess the influence of these parameters in their higher accident rate. The conclusions provided can enable public administrations to modify enforcement laws, regarding time control of driving and PMVI.Proyecto financiado por el Ministerio de Fomento en el marco del Plan I+D+i 2008/2011: Desarrollo y aplicación de una metodología integrada para el estudio de los accidentes de tráfico con implicación de furgonetas (P24/08)”. FURGOSEG

A robust observer based on H∞ filtering with parameter uncertainties combined with Neural Networks for estimation of vehicle roll angle

Nowadays, one of the main objectives in road transport is to decrease the number of accident victims. Rollover accidents caused nearly 33% of all deaths from passenger vehicle crashes. Roll Stability Control (RSC) systems prevent vehicles from untripped rollover accidents. The lateral load transfer is the main parameter which is taken into account in the RSC systems. This parameter is related to the roll angle, which can be directly measured from a dual-antenna GPS. Nevertheless, this is a costly technique. For this reason, roll angle has to be estimated. In this paper, a novel observer based on H∞ filtering in combination with a neural network (NN) for the vehicle roll angle estimation is proposed. The design of this observer is based on four main criteria: to use a simplified vehicle model, to use signals of sensors which are installed onboard in current vehicles, to consider the inaccuracy in the system model and to attenuate the effect of the external disturbances. Experimental results show the effectiveness of the proposed observer.This work is supported by the Spanish Government through the Project TRA2013-48030-C2-1-R, which is gratefully acknowledged

Experimental study and analytical model of bleed valve orifice influence of a high-performance shock absorber on vehicle dynamics

The aim of this study is to model the influence of the bleed orifice area of a high-performance damper on the dynamic behaviour of a vehicle. For this purpose, a mathematical model of a monotube high-performance damper is developed, considering the presence of two regulation ways on the effect of bleed valve orifice of the damper. An application of changes in damper setup in the field of practical enables to analyse the influence of the positions of both rod and bottle selectors on the damping force. The proposed damper model is validated experimentally. The analysis of the dynamic behaviour is performed through a quarter vehicle simulation under different conditions of road roughness and speed regimes. In addition, an analysis of the frequency response of the sprung mass acceleration by means of power spectral density was applied to obtain the dynamic response of the quarter vehicle model. Results show that the influence of the bleed orifice is magnified for low speeds and for profile roads with few variations on surface. This effect is reduced for both the increasing vehicle speed and the profiles with greater difference in irregularities