• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Coupling the effects of rubber aging and wear and studying its effect on motorcycle performance

Kurup, Alekh Manoshkumar 22 December 2023 (has links)
Master of Science / Rubber is a widely used material globally and undergoes significant changes as it ages. However, the specific consequences of rubber aging on tires and vehicle dynamics remain a relatively underexplored domain. This study delves into the effects of rubber aging on tires and motorcycle dynamics. A Dynamical Mechanical Analysis (DMA) test was performed to study the effect of rubber aging combined with computer simulation models to predict how much the rubber wears out over time. It was found that as rubber gets older it doesn't wear out much faster. This might be because the changes in the rubber properties as it ages are very small. The rubber material also gets stiffer as it ages, leading to minimal differences in the wear rate. The Magic Formula (MF) model was used in this study to model motorcycle tires. A 3-4% increase in the longitudinal and lateral tire forces was observed as the tire aged. This was followed by simulations to study the motorcycle behavior during straight-line and turning motion. It was found that the front tires of the motorcycle had an approximately 3% change in the forces experienced, while the forces experienced by the rear tires only changed by 1-2% with respect to aging. These results are similar to the results obtained by other researchers on the effects of rubber aging on car performance. Thus, this study stresses the importance of understanding how tires change over time and how that affects how motorcycles perform.
2

[en] ANALYSIS OF CONTROL STRATEGIES FOR AUTONOMOUS SCALE MOTORCYCLES STABILIZATION AND TRAJECTORY TRACKING / [pt] ANÁLISE DE ESTRATÉGIAS DE CONTROLE PARA ESTABILIZAÇÃO E ACOMPANHAMENTO DE TRAJETÓRIAS DE MOTOCICLETAS AUTÔNOMAS EM ESCALA

MARILIA MAURELL ASSAD 13 August 2018 (has links)
[pt] Veículos autônomos são um problema recente, com aplicação em carros e motocicletas ainda nos estágios iniciais. Além das dificuldades inerentes de fazer um veículo mover-se independentemente, a motocicleta autônoma deve permanecer estável em qualquer velocidade e trajetória. O objetivo principal deste trabalho é desenvolver uma motocicleta elétrica autônoma com sistema de instrumentação de baixo custo. Para tanto, foi analisado um modelo dinâmico de motocicleta, capaz de reproduzir o comportamento real e permitindo a implementação de estratégias de controle linear em tempo real. O controlador tem dois objetivos diferentes: manter a motocicleta estável e seguir uma trajetória desejada, de forma autônoma. Experimentos foram realizados com a motocicleta de escala reduzida com o objetivo de caracterizar seus elementos; as estratégias de controle propostas foram simuladas com o modelo dinâmico ajustado. Por fim, os algoritmos de controle são aplicados ao sistema real através de uma plataforma atuada capaz de reproduzir a dinâmica de veículos de duas rodas. O presente trabalho é uma ferramenta para o ensino de engenharia, envolvendo estudantes de diferentes níveis em torno de um problema complexo. O sistema permite uma aprendizagem contínua com dificuldade crescente, envolvendo temas como dinâmica de multicorpos; análise de resultados através de simulações de software; eletrônica e filtros na instrumentação embutida e técnicas de controle para manter o sistema estável em todos os caminhos desejados, culminando na aplicação experimental dos conceitos citados. / [en] Autonomous vehicles are an interesting and recent problem, with its application in cars and motorcycles still in its early stages. In addition to the inherent difficulties in making a vehicle move independently, the autonomous motorcycle has to be able to remain stable at any speed and trajectory. The vehicle s stability can be achieved by different solutions and control techniques. The main objective of this work is to develop an autonomous electric motorcycle with low cost sensing system. For this, a dynamic model of two-wheeled vehicles is analyzed, capable of describing the dynamic behavior while being simple enough to allow the implementation of real-time linear control strategies. The controller has two different objectives: to maintain the motorcycle stable and to follow a desired trajectory, in an autonomous way. Experiments were carried out with the small scale motorcycle aiming to characterize its elements for the theoretical model; then the proposed control strategies were simulated with the adjusted dynamic model. Finally, the control algorithms are applied to the real system through an actuated platform capable of reproducing the dynamic behavior of single-track vehicles. At last, the present work is a tool for teaching engineering, involving multilevel students around a complex, but familiar, problem. The system allows for continuous learning with increasing difficulty, involving multibody dynamics, experimental results analysis via software simulations, electronics and filters present in the embedded instrumentation and many control techniques to keep the system stable in every desired path, culminating in the experimental application of cited concepts.

Page generated in 0.0457 seconds