A Novel Universal Corner Module for Urban Electric Vehicles: Design, Prototype, and Experiment

This thesis presents the work of creating and validating a novel corner module for a three-wheeled urban electric vehicle in the tadpole configuration. As the urban population increases, there will be a growing need for compact, personal transportation. While urban electric vehicles are compact, they are inherently less stable when negotiating a turn, and they leave little space for passengers, cargo and crash structures. Corner modules provide an effective solution to increase the space in the cabin and increase the handling capabilities of the vehicle. Many corner module designs have been produced in the hopes of increasing the cabin space and improving the road holding capabilities of the wheel. However, none have been used to increase the turning stability of the vehicle via an active camber mechanism while remaining in an acceptable packaging space. Active camber mechanisms are also not a new concept, but they have not been implemented in a narrow packaging space with relatively large camber angle. Parallel mechanism research and vehicle dynamics theory were combined to generate and analyse this new corner module design. The corner module increases the stability of the urban electric vehicle by cambering the front wheels to -15 degrees when the vehicle is turning. The camber angle augmentation increases the track width which subsequently decreases the center of gravity height. These changes accumulated to increase the stability of the vehicle. The corner module uses two actuators to control the orientation of the wheel. Bias ply tires are incorporated into the corner module to enable the large camber angles. To increase the space in the cabin, the front left and right wheels are not connected by a mechanical linkage, and the motors are mounted to the wheel rim. While disc brakes are integrated into the corner module, the motor is also capable of regenerative braking. By integrating this corner module into urban electric vehicles, the vehicle size and pollution can be reduced while increasing the cabin space and public space

Applied Mathematics to Mechanisms and Machines

This book brings together all 16 articles published in the Special Issue "Applied Mathematics to Mechanisms and Machines" of the MDPI Mathematics journal, in the section “Engineering Mathematics”. The subject matter covered by these works is varied, but they all have mechanisms as the object of study and mathematics as the basis of the methodology used. In fact, the synthesis, design and optimization of mechanisms, robotics, automotives, maintenance 4.0, machine vibrations, control, biomechanics and medical devices are among the topics covered in this book. This volume may be of interest to all who work in the field of mechanism and machine science and we hope that it will contribute to the development of both mechanical engineering and applied mathematics

On the constraints violation in forward dynamics of multibody systems

It is known that the dynamic equations of motion for constrained mechanical multibody systems are frequently formulated using the Newton-Euler’s approach, which is augmented with the acceleration constraint equations. This formulation results in the establishment of a mixed set of partial differential and algebraic equations, which are solved in order to predict the dynamic behavior of general multibody systems. The classical resolution of the equations of motion is highly prone to constraints violation because the position and velocity constraint equations are not fulfilled. In this work, a general and comprehensive methodology to eliminate the constraints violation at the position and velocity levels is offered. The basic idea of the described approach is to add corrective terms to the position and velocity vectors with the intent to satisfy the corresponding kinematic constraint equations. These corrective terms are evaluated as function of the Moore-Penrose generalized inverse of the Jacobian matrix and of the kinematic constraint equations. The described methodology is embedded in the standard method to solve the equations of motion based on the technique of Lagrange multipliers. Finally, the effectiveness of the described methodology is demonstrated through the dynamic modeling and simulation of different planar and spatial multibody systems. The outcomes in terms of constraints violation at the position and velocity levels, conservation of the total energy and computational efficiency are analyzed and compared with those obtained with the standard Lagrange multipliers method, the Baumgarte stabilization method, the augmented Lagrangian formulation, the index-1 augmented Lagrangian and the coordinate partitioning method.The first author expresses his gratitude to the Portuguese Foundation for Science and Technology through the PhD grant (PD/BD/114154/2016). This work has been supported by the Portuguese Foundation for Science and Technology with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 – Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941.info:eu-repo/semantics/publishedVersio

Suspension parameters analysis for different track conditions

Dissertação de mestrado integrado em Engenharia Mecânica (área de especialização em Sistemas Mecatrónicos)Este trabalho, aqui apresentado, tem como objetivo o estudo do comportamento do sistema de suspensão de um veículo ao atravessar estradas com obstáculos, como lombas ou buracos. Para atingir este objetivo, uma vasta revisão literária foi feita. Sendo este um tópico extenso, três tipos de revisão foram feitos. Primeiro, a um estudo global à tecnologia usava hoje em dia em pneus e nos sistemas de suspensão de veículos foi compilado. Uma breve menção à cinemática de veículos é empreendida. De seguida, a dinâmica do contacto pneu/solo é sistematicamente explanada, para compreender os diversos modelos de pneu (força) existentes. Adicionalmente, os conceitos fundamentais da análise da dinâmica multicorpo são expostos para justificar a modelação do veículo como um sistema multicorpo. Com toda a teoria apresentada, os conceitos previamente explicados são aplicados na prática para a formulação de um método que visa estimar a trajetória de um veículo atravessando uma qualquer estrada. O primeiro passo a executar é a escolha do modelo de pneu a utilizar. Percebe-se que se deve usar modelos matemáticos, culminando na escolha da Magic Formula. Os passos seguintes consistem na introdução de uma metodologia, que estima o contacto entre um pneu e o solo, para simular as dinâmicas pneu/solo de um veículo. Dois métodos diferentes são expostos: o primeiro para estradas completamente planas, sem obstáculos; o segundo, para estradas com obstáculos, como lombas ou buracos. Este modelo é posteriormente inserido num programa de análise das dinâmicas multicorpo, MUBODYNA3D, e diversas simulações são realizadas. Estas simulações começam pela definição do veículo como um sistema multicorpo, com corpos conectados por juntas cinemáticas. As primeiras simulações são realizadas numa estrada plana para validar os modelos e metodologias previamente criadas. O integrador, que integra os resultados das equações do movimento para prever a trajetória, é refinado. Finalmente, simulações com estradas com obstáculos são geradas. Por fim, os resultados dessas simulações são discutidos, percebendo-se que apresentam um valor inesperado. Ao atravessar um obstáculo, as rodas perdem o contacto com a superfície, provocando a descolagem do carro. No entanto, é concluído que a análise de sistemas multicorpo é de extrema relevância para a simulação de realidades complexas, produzindo resultados precisos.This work, hereby presented, has a primary target of studying the behaviour of a road vehicle’s suspension system, while it is traversing roads with big obstacles, such as potholes or speed bumps/humps. To accomplish this task, a broad literature review was made. Since this is an extensive topic, three types of review were made. Firstly, an overview of the state-of-the-art technology used in tires and suspension systems nowadays is compiled. A brief mention to vehicle kinematics is also made. Then, the dynamics of the contact tire/road are systematically explained, in order to understand the diverse tire force models that exist. Lastly, a rundown of the fundamental concepts of multibody dynamics analysis is exposed to substantiate the modelling of a vehicle as a multibody system later on. With the theory behind, all concepts previously abridged are put to practice, into the formulation of a method to estimate the trajectory of a vehicle crossing a certain road. The first step to execute this is to choose the tire force model to use. It is seen that, in this case, the mathematical models are the best choice, which culminates in the selection of the Magic Formula model. The following steps consist of introducing the contact estimation methodology created to simulate the tire/road dynamics of a vehicle. Two different methods are exposed: the first for fully flat roads, with no obstacles; the second, for road that possess obstacles, like bumps for example. This model is then inserted into a multibody dynamics analysis program, MUBODYNA3D, and some forward dynamic simulations are performed. These simulations start with the definition of the vehicle as a multibody system, with bodies connected by kinematic joints. The first simulations are performed in flat roads to validate the models and methodologies created. The solver, that integrates the results of the equations of motion to predict the trajectory, are then refined. Finally, simulations using roads with obstacles are conducted and the results analysed. In the end, the simulations result in some unexpected behaviour from the vehicle. While crossing an obstacle, it tends to lose contact with the surface and, thus, lift off the road, which is unrealistic. Nonetheless, it is concluded that multibody systems analysis is extremely important to simulate and analyse complex realities, with precise results

Combining Sensors and Multibody Models for Applications in Vehicles, Machines, Robots and Humans

The combination of physical sensors and computational models to provide additional information about system states, inputs and/or parameters, in what is known as virtual sensing, is becoming increasingly popular in many sectors, such as the automotive, aeronautics, aerospatial, railway, machinery, robotics and human biomechanics sectors. While, in many cases, control-oriented models, which are generally simple, are the best choice, multibody models, which can be much more detailed, may be better suited to some applications, such as during the design stage of a new product

Robot Manipulators

Robot manipulators are developing more in the direction of industrial robots than of human workers. Recently, the applications of robot manipulators are spreading their focus, for example Da Vinci as a medical robot, ASIMO as a humanoid robot and so on. There are many research topics within the field of robot manipulators, e.g. motion planning, cooperation with a human, and fusion with external sensors like vision, haptic and force, etc. Moreover, these include both technical problems in the industry and theoretical problems in the academic fields. This book is a collection of papers presenting the latest research issues from around the world

Modelling the Fluid Mechanics of Cilia and Flagella in Reproduction and Development

Cilia and flagella are actively bending slender organelles, performing functions such as motility, feeding and embryonic symmetry breaking. We review the mechanics of viscous-dominated microscale flow, including time-reversal symmetry, drag anisotropy of slender bodies, and wall effects. We focus on the fundamental force singularity, higher order multipoles, and the method of images, providing physical insight and forming a basis for computational approaches. Two biological problems are then considered in more detail: (1) left-right symmetry breaking flow in the node, a microscopic structure in developing vertebrate embryos, and (2) motility of microswimmers through non-Newtonian fluids. Our model of the embryonic node reveals how particle transport associated with morphogenesis is modulated by the gradual emergence of cilium posterior tilt. Our model of swimming makes use of force distributions within a body-conforming finite element framework, allowing the solution of nonlinear inertialess Carreau flow. We find that a three-sphere model swimmer and a model sperm are similarly affected by shear-thinning; in both cases swimming due to a prescribed beat is enhanced by shear-thinning, with optimal Deborah number around 0.8. The sperm exhibits an almost perfect linear relationship between velocity and the logarithm of the ratio of zero to infinite shear viscosity, with shear-thickening hindering cell progress.Comment: 20 pages, 24 figure

MUSME 2011 4 th International Symposium on Multibody Systems and Mechatronics

El libro de actas recoge las aportaciones de los autores a través de los correspondientes artículos a la Dinámica de Sistemas Multicuerpo y la Mecatrónica (Musme). Estas disciplinas se han convertido en una importante herramienta para diseñar máquinas, analizar prototipos virtuales y realizar análisis CAD sobre complejos sistemas mecánicos articulados multicuerpo. La dinámica de sistemas multicuerpo comprende un gran número de aspectos que incluyen la mecánica, dinámica estructural, matemáticas aplicadas, métodos de control, ciencia de los ordenadores y mecatrónica. Los artículos recogidos en el libro de actas están relacionados con alguno de los siguientes tópicos del congreso: Análisis y síntesis de mecanismos ; Diseño de algoritmos para sistemas mecatrónicos ; Procedimientos de simulación y resultados ; Prototipos y rendimiento ; Robots y micromáquinas ; Validaciones experimentales ; Teoría de simulación mecatrónica ; Sistemas mecatrónicos ; Control de sistemas mecatrónicosUniversitat Politècnica de València (2011). MUSME 2011 4 th International Symposium on Multibody Systems and Mechatronics. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/13224Archivo delegad

Modelling chassis flexibility in vehicle dynamics simulation

This thesis deals with the development of advanced mathematical models for the assessment of the influence of chassis flexibility on vehicle handling qualities. A review of the literature relevant to the subject is presented and discussed in the first part of the thesis. A preliminary model that includes chassis flexibility is then developed and employed for a first assessment of the significance of chassis flexibility. In the second part of the thesis a symbolic multibody library for vehicle dynamics simulations is introduced. This library constitutes the basis for the development of an advanced 14-degrees-of-freedom vehicle model that includes chassis flexibility. The model is then demonstrated using a set of data relative to a real vehicle. Finally, simulation results are discussed and conclusions are presented. The advanced model fully exploits a novel multibody formulation which represent the kinematics and the dynamics of the system with a level of accuracy which is typical of numeric multibody models while retaining the benefits of purpose-developed hand- derived models. More specifically, a semi-recursive formulation, a velocity projection technique and a symbolic development are, for the first time, coupled with flexible body modelling. The effect of chassis flexibility on vehicle handling is observed through the analysis of open- and closed-loop manoeuvres. Results show that chassis flexibility induces variations of lateral load transfer distribution and suspension kinematics that sensibly affect the steady-state behaviour of the vehicle. Further effects on dynamic response and high-speed stability are demonstrated. Also, optimal control theory is employed to demonstrate the existence of a strict correlation between chassis flexibility and driver behaviour. The research yields new insights into the dynamics of vehicles with a flexible chassis and highlights critical aspects of chassis design. Although the focus is on sports and race cars, both the modelling approach and the results can be extended to other vehicles.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Proceedings of the ECCOMAS Thematic Conference on Multibody Dynamics 2015

This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: ● Formulations and Numerical Methods ● Efficient Methods and Real-Time Applications ● Flexible Multibody Dynamics ● Contact Dynamics and Constraints ● Multiphysics and Coupled Problems ● Control and Optimization ● Software Development and Computer Technology ● Aerospace and Maritime Applications ● Biomechanics ● Railroad Vehicle Dynamics ● Road Vehicle Dynamics ● Robotics ● Benchmark ProblemsPostprint (published version