Building a comprehensive energy model for off-highway vehicles with emphasis on vehicle thermal control systems

Utilizing machine and thermal system simulations (vehicle energy models) can be very helpful for vehicle manufacturing companies to develop a machine with acceptable component temperatures, less heat loads to the vehicle cooling systems, and reduced emissions that will also reduce overall product development cycle. Energy models of vehicles were developed mostly in the automotive industry, and most of these studies were based on partial energy models. The aim of this research study was to create a comprehensive energy model for agricultural machinery, which will be a basis for future work on similar products. A tractor model from a Midwest off-road machinery manufacturing company was selected as a starting point for modeling. The work in creating the model has been presented in detail. Verification of the simulation model has been carried out using the results from three different wind tunnel tests that have been conducted by the Midwest company; namely the PTO test, the AXLE test, and the high-speed wind tunnel transport test. The critical parameters were selected to be analyzed for each test were the top tank Temperature, the intake manifold temperature, the oil cooler inlet temperature, the oil cooler outlet temperature, the fuel cooler inlet temperature, the fuel cooler outlet temperature, the fan speed, the engine speed, the PTO torque and the axle torque. Based on the analysis of data, it was concluded that the comprehensive energy model is adequately representing the selected tractor model, from the energy distribution and the component temperatures point of view. Therefore, it can be used for specific field missions that are not easy to conduct in a wind tunnel set up to acquire data for the critical parameters

Development of an Automated Mechanical Intra-Row Weeder for Vegetable Crops

Weed management is one of the tedious operations in vegetable production. Because of labor costs, time and tedium, manual weeding is unfavorable. The introduction of chemical weed control methods has alleviated these undesirable factors. However, the emergence of herbicide-resistant weeds, environmental impact and increasing demand for chemical free foods has led to investigations of alternative methods of weed control. Most implements employing mechanical cultivation cannot perform weed control close to the crops, and existing intra-row weeders have limitations. A mechanical weeding actuation system was designed, and a prototype was constructed. This actuator was developed to mechanically control intra-row weed plants. The mechanical weeding actuator consisted of a belt drive system powered by an integrated servo motor and a rotating tine weeding mechanism powered by a brushless dc motor. One of the major challenges in this project was to properly design the actuator and its weeding mechanism for effective intra-row weed control. A prototype actuator was manufactured and a series of tests was conducted to determine actuator efficacy and the corresponding force and speed requirements of the actuator. The actuator would be combined with a machine vision system for detecting crop plant locations and guiding the weeding actuator to execute mechanical weeding operations without damaging crops. In the first field experiment, the performance of the first version of the intra-row weeder was investigated across three factors: working depth, travel speed and tine mechanism rotational speed. There was evidence of differences in weed control efficacy across travel speeds. Using least square means, the slowest travel speed of 0.8 km/h had an average reduction in weed canopy area of 58.2% with standard error of 2.7% compared with the medium travel speed of 1.6 km/h with an average reduction in weed canopy area of 52.6% with standard error of 2.7%. The fastest travel speed of 2.4 km/h had an average reduction in weed canopy area of 42.4% with standard error of 2.7%.There was no statistical evidence of differences in power consumption across working depth, travel speed, or rotational speed. With increasing working depths, reduction in weed canopy area and power consumption tended to increase. With a revised version of the rotating tine weeding mechanism, a second field experiment was also conducted using three factors; tine shape, travel speed and rotational speeds. The results showed that there was no significant difference in reduction in weed canopy area across tine shapes. However, there was some indication that weed control efficacy decreased as travel speed increased. There was evidence of differences in power consumption across rotational speeds. The fastest rotation speed, 536 rpm, had a mean power consumption of 182 W and standard error of 9.4 W. The lowest rotation speed, 350 rpm, had the lowest mean power consumption of 123.5 W and a standard error of 9.4W

Towards control over motion at the molecular and submolecular level

Een van de hoofddoelstellingen van de moderne scheikunde is controle te krijgen over beweging en het verrichten van werk op het moleculaire en submoleculaire niveau. Het introductiehoofdstuk van dit proefschrift richt zich erop een overzicht te geven van de talrijke pogingen van wetenschappers om kunstmatige motorsystemen te ontwikkelen waarvan de grote meerderheid inspiratie krijgt van de dynamische systemen in de natuur. De focus ligt op draaibeweging en responsieve moleculen op oppervlakken. Niettegenstaande al de aandacht die de nanowetenschap recentelijk heeft gekregen, is het duidelijk dat de wetenschap nog in de kinderschoenen staat op dit gebied en dat er nog erg veel werk nodig is om de voornoemde doelstellingen te bereiken. Het in dit proefschrift beschreven onderzoek richt zich op pogingen om de beweging aan het moleculaire en submoleculaire niveau onder controle te krijgen. In de hoofdstukken 2 tot en met 4 worden het ontwerp en de synthese van nieuwe moleculen beschreven om een beter begrip te krijgen van de bewegingen van moleculen op oppervlakken. De moleculen werden eerst in oplossing bestudeerd. Van een aantal van de onderzochte moleculen wordt verwacht dat ze zich onder invloed van licht op oppervlakken kunnen verplaatsen. De hoofdstukken 5 en 6 zijn daarentegen op de draaibeweging gericht. In hoofdstuk 5 gaat het over het afstemmen van de rotatiesnelheid van de unidirectionele, op sterisch gehinderde alkenen gebaseerde moleculaire rotatiemotoren die met licht worden aangedreven. Hoofdstuk 6 beschrijft het ontwerp, de synthese en de studie van de nieuwe op binaftyl gebaseerde moleculaire rotoren met het doel om de rotatiesnelheid af te stemmen door middel van zowel sterische hinder als allosterische regulatie. Al met al demonstreert het in dit proefschrift gepresenteerde onderzoek verscheidene manieren om de beweging op moleculair en submoleculair niveau onder controle te krijgen en dit draagt bij aan een beter begrip van de manier waarop moleculen bewegen

Pneumatic Tire

For many years, tire engineers relied on the monograph, \u27Mechanics of Pneumatic Tires\u27, for detailed information about the principles of tire design and use. Published originally by the National Bureau of Standards, U.S. Department of Commerce, in 1971, and a later (1981) edition by the National Highway Traffic Safety Administration (NHTSA), U.S. Department of Transportation, it has long been out of print. No textbook or monograph of comparable range and depth has appeared since. While many chapters of the two editions contain authoritative reviews that are still relevant today, they were prepared in an era when bias ply and belted-bias tires were in widespread use in the United States and thus did not deal in a comprehensive way with more recent tire technology, notably the radial constructions now adopted nearly universally. In 2002, it was preposed that NHTSA should sponsor and publish electronically a new book on passenger tires, under editorship of the University of Akron, to meet the needs of a new generation of tire scientists, engineers, designers, and users. This text is the outcome. The chapter authors are recognized authorities in tire science and technology. They have prepared scholarly and up-to-date reviews of the various aspects of passenger car tire design, construction and use, and included test questions in many instances, so that the book can be used for self-study or as a teaching text by engineers and others entering the tire industry

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

Modeling and Simulation in Engineering

This book provides an open platform to establish and share knowledge developed by scholars, scientists, and engineers from all over the world, about various applications of the modeling and simulation in the design process of products, in various engineering fields. The book consists of 12 chapters arranged in two sections (3D Modeling and Virtual Prototyping), reflecting the multidimensionality of applications related to modeling and simulation. Some of the most recent modeling and simulation techniques, as well as some of the most accurate and sophisticated software in treating complex systems, are applied. All the original contributions in this book are jointed by the basic principle of a successful modeling and simulation process: as complex as necessary, and as simple as possible. The idea is to manipulate the simplifying assumptions in a way that reduces the complexity of the model (in order to make a real-time simulation), but without altering the precision of the results

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

Theoretical studies of molecular machines

Only volume 2 has been digitized.Molecular machines are essential components of living organisms. They are highly efficient and robust, much more than their macroscopic analogs. This stimulated growing interest in construction of artificial molecular machines with a set of functions which may be controlled in a specific way. Such man-made molecular complexes are designed as the building blocks for future nanotechnological devices. During the last decades many new molecular machines have been synthesized and characterized by various experimental techniques. This significantly increased our knowledge about systems of such kind and their functioning. However, there are only a few real applications of molecular machines. This is because the fundamental principles of operation of such single-molecule systems are not well understood. Existing theoretical studies, although very helpful, are still very sparse. This is because the molecular machines are very complex systems, comprising up to thousands atoms. Thus the progress in our understanding of nanoscale materials is tightly related to development of efficient computational and theoretical methodologies. In this work we studied two large classes of molecular machines: surface-moving nanocars and molecular rotors/motors, working on the surfaces and in crystalline state. In particular we studied the role of the internal interactions of these machines as well as their interactions with the environment. This included the flexibility of the molecules, including the rotation of the nanocars' wheels, effects of surface and rotors symmetry, charge transfer effects as well as many other factors. We have found out relations which determine the properties of studied classes of molecular machines. The development of computational and theoretical methods was another essential part of this work. In particular we have developed a family of the surface-molecule interaction potentials, aimed to performing long time scale and molecular simulations of complex systems. We also developed a physics-based model of the charge transfer happening between metals and the nanocars. This opened new ways to control such molecular machines. We also developed a theoretical framework to predict response of molecular rotors on various types of driving. Finally, we developed new and improved existing rigid-body molecular dynamics methods and extensively used them in our studies of molecular machines