Cal Poly Supermileage Dynamometer

Our senior project involves designing a chassis dynamometer capable of simulating variable loads for the Cal Poly Supermileage Vehicle (SMV) team. The chassis dynamometer we are developing uses an alternator to develop additional resistance that the vehicle will have to overcome while testing. To implement a control system for the variable load, we use an Arduino Nano paired with multiple sensors and drivers. This control system allows the user to select different levels of resistance that correlate with different road grades. We designed a custom Printed Circuit Board (PCB) that will contain all the electrical components needed for the control system. We designed a mechanical system that makes use of belt drive pulleys to link the resistance provided by the alternator to the rotating drum and shaft assembly. Our final design also includes a software system with a Graphical User Interface (GUI) that allows for users of the SMV team to easily select various road grades and see the results of their dynamometer testing. Our design will allow the SMV team to make more efficient upgrades to the powertrain of both their gas and electric vehicles

ESSE 2017. Proceedings of the International Conference on Environmental Science and Sustainable Energy

Environmental science is an interdisciplinary academic field that integrates physical-, biological-, and information sciences to study and solve environmental problems. ESSE - The International Conference on Environmental Science and Sustainable Energy provides a platform for experts, professionals, and researchers to share updated information and stimulate the communication with each other. In 2017 it was held in Suzhou, China June 23-25, 2017

DEVELOPMENT OF A DESIGN METHOD TO REDUCE CHANGE PROPAGATION EFFECTS

ABSTRACT This dissertation presents a design method to reduce engineering changes caused due to change propagation effect. The method helps designers to systematically plan a verification, validation, and test (VV&T) plan. The rationale behind such a method is founded on a well-accepted principle that a robust validation plan can reduce design changes. However, such method has not yet been developed in mechanical engineering domain, so a method from software engineering has been adopted and extended to address the limitations in the existing design evaluation tools. Tools extensively used in industry, such as FMEA, and in academia have been reviewed to determine if they can identify different propagation pathways including variant, behavior, organization, and geometric pathways. As a result, it is found that variant and organizational pathways are not identified in any of these tools -- propagation in these pathways have caused major product failure in commercial vehicle and automatic fire sprinkler manufacturing industries. A seven-step VV&T method is proposed to address the aforementioned gap in which each step is tailored to suit mechanical engineering needs. The major contribution is developing the construct to identify variant and organization pathways and a prescriptive method. It has been validated in a leading commercial vehicle manufacturer, one of the passenger car manufacturing giants, and an automatic fire sprinkler manufacturer. The results from these three companies indicate the proposed VV&T method enables designers to identify variant and organizational pathways and evaluate them, which in turn can reduce design changes due to propagation effects. Objective evidence obtained from the fire sprinkler manufacturing company supports this claim. \u27If we know what assembly combination to test with, testing is not a problem...and if it can prevent a failure of this magnitude --I think this method can --it can be extremely beneficial...\u27 - Project engineer, commercial vehicle manufacture

Towards Energy-Efficient Electrified Mobile Hydraulics : Considering Varying Application Conditions

In the face of global warming, companies in all kinds of industries need to take measures to reduce the use of fossil fuels, which is explicitly enforced by more and more upcoming emission legislation in many countries. In the case of heavy-duty mobile machines (HDMMs), a currently high-emitting sector, the most feasible method of reducing harmful emissions during operation is battery-based electrification. However, the relatively low capacities and high costs of available battery packs are restricting the operation times as well as upper power limits of battery-electric HD-MMs—at least under economically feasible conditions. In this scenario, the typically low energy-efficiencies of conventional hydraulic systems, which are essential for realizing linear actuation on HDMMs, are becoming more critical than ever before, and more efficient alternative concepts are required. As an answer to this demand, this thesis and the six publications on which it is based analyze how alternative hydraulic concepts for electrified HDMMs should look like, and two specific concepts are proposed as well as evaluated. In this scope, the focus is not only on improving the efficiency but also on other aspects that can prevent or accelerate the success of alternative hydraulic concepts on the market, such as costs and feasibility. Since those aspects cannot be analyzed in isolation from the application conditions, the essential characteristics of HDMMs and the differences of those characteristics between HDMM types are elaborated systematically. Furthermore, the implications of the transition from internal combustion engines (ICEs) to electric machines (EMs) as the prime movers for hydraulic pumps are identified by means of a literature review. Considering the insights from the analyses of those aspects, already existing hydraulic concepts—i.e., conventional as well as proposed alternatives for improved efficiency—are reevaluated, and beneficial elements of those concepts are filtered out for constructing two new concepts. Those two proposed concepts are characterized by a modular approach in which actuators can be valve-controlled, which might be less efficient but more cost-effective, or pump-controlled, as an alternative for more efficient yet costly actuation of selected functions on the HDMM. Simulation studies are used to demonstrate the efficiency of both concepts under varying configurations that are enabled through the modular nature of the concepts, and the differences in applying them on a telehandler, wheel loader, or excavator are analyzed. For the second concept, which is based on displacement-control and performed best in the simulations, a cost analysis is used to prove additionally that reasonably short payback times of the increased investment costs can be reached in different scenarios. Furthermore, the efficiency performance as well as feasibility—in terms of using commercially available components only and achieving good controllability—are experimentally validated on a telehandler

Design feasability of the electrical network for turboelectric aircraft propulsion.

The motivation for this research is the need for safer and more environmentally friendly air transport system. Electrical propulsion systems have been identified as a potential method for improving aircraft performance going forward. The implementation of electrical drive trains for future aircraft propulsion comes with many challenges, due to the novelty and scale of the intended deployments. Major technological advancements and research are ongoing at system and component level to meet this ambition. However, the feasibility aspects of these studies have focused more on the engine side than on the electrical aspects, especially with regards to system reliability and stability. These have been considered in the earlier proposed sizing methods, using assumed fault and transient current magnitudes. Such assumption implies that the control and protection systems, may not properly handle abnormal operational scenarios. The aim of this research is to establish a procedure for sizing components of an electric propulsion system considering reliability and stability. The major objective is to properly quantify the operating parameters in non-steady state operations, like transients and fault scenarios, and establish that components are operating within their thermal limits at all operational stages. The contribution of this work is the development of a method that incorporates stability and reliability in the sizing process of electrical propulsion networks. The practicality of the proposed methods has also been validated experimentally, using a test facility set up for this study. The impact of this work is the reduction of the design uncertainties, resulting from assumed fault and transient characteristics of an electrical propulsion system. The results show that the assumptions in earlier researches do not suffice for the investigated architectures. A considerable mass penalty is incurred, with the power electronic devices having to be sized for slightly higher than the maximum transient currents.PhD in Aerospac

A non-conformance classification and rapid control method for improved product validation

Product quality is a topic of significant industrial importance and has been the subject of ongoing research over many years. However, the study of non-conformance reduction in the pre-production stage of product development has received only limited attention. Although products undergo chronological and rigid assessments, there are still non-conformances which are detected late in development stages particularly in pre-production. Furthermore, these non-conformances are problematic when rectification cannot be found rapidly and these problems are then carried over into production. The research, which is based on consumer electronic product, addresses product nonconformance in the pre-production. The work reported in this thesis focuses on the identification and control of non-conformances to facilitate improved product validation and aids the pre-production team in product assessment and decision making. [Continues.

SUSTAINABLE ENERGY HARVESTING TECHNOLOGIES – PAST, PRESENT AND FUTURE

Chapter 8: Energy Harvesting Technologies: Thick-Film Piezoelectric Microgenerato

Ceramic coatings on non-valve metals deposited by plasma electrolysis

A modified plasma electrolytic oxidation (PEO) treatment has been successfully developed for the non-valve metals of Fe and Cu in electrolyte containing sodium aluminate and sodium phosphate. This process could also be termed as plasma electrolytic aluminating (PEA) since the formation of passive films mainly relies on the aluminate ions. The passive film will hinder the current flow and cause charge build-up. When a critical voltage is reached, dielectric breakdown of the passive film will ignite the sparks. X-ray photoelectron spectroscopy (XPS) analyses indicate the passive film formed on the Fe consist of FeAl2O4, which means iron substrate participated in the reaction. On the other hand, the copper substrate was not involved in the passive film formed on the Cu, which consists of Al(OH)3. The different mechanisms could be attributed to the different reduction potentials of Fe and Cu. Taguchi analyses were used to investigate the influence of selected process parameters, including the concentration of NaAlO2 in the electrolyte (C), the frequency (f) and duty cycle (δ) of the power supply. ANOVA analysis revealed that C has the most significant contribution to hardness, corrosion resistance and thickness. While f has significant influence on hardness and corrosion resistance, δ contributes significantly to the thickness. Higher frequency means shorter duration of a single discharge which leads to denser coating with higher hardness and corrosion resistance. Higher duty cycle represents the higher power input during the PEA treatment. Therefore, the coating’s thickness increased with higher duty cycle. The coating prepared on iron substrate mainly consists of Al2O3 and FeAl2O4. The hardness, polarization resistance and thermal conductivity of the coating were 822 HV, 296 kΩ·cm2 and ~0.5 W/(m·K), respectively. The low thermal conductivity comes from the mesopores, nano-grains and amorphous materials. After cyclic thermal shock tests, the coating retained its porous structure without spallation. Post-treatments like electroless nickel plating (EP) and sol-gel silica coating were applied to seal the open pores and cracks. Both the PEA-EP and PEA-SiO2 hybrid coatings could retain good corrosion resistance after immersed in sodium chloride solution for five days, while the PEA coating degraded due to pitting corrosion at these open pores and cracks. The coating deposited on pure copper consists of ceramic matrix (Al2O3 and Cu2O) embedded with Cu particles. The amount of Cu particles increased with increased coating thickness, which could be attributed to intensified plasma discharges. The hardness, polarization resistance and thermal conductivity of the coating were 1050 HV, 141.7 kΩ·cm2 and ~5.1 W/(m·K), respectively. The increased thermal conductivity could be attributed to the presence of metallic Cu. The coating has excellent wear and corrosion resistance, which might be used for wear-corrosion protection of copper alloys

Towards a Common Software/Hardware Methodology for Future Advanced Driver Assistance Systems

The European research project DESERVE (DEvelopment platform for Safe and Efficient dRiVE, 2012-2015) had the aim of designing and developing a platform tool to cope with the continuously increasing complexity and the simultaneous need to reduce cost for future embedded Advanced Driver Assistance Systems (ADAS). For this purpose, the DESERVE platform profits from cross-domain software reuse, standardization of automotive software component interfaces, and easy but safety-compliant integration of heterogeneous modules. This enables the development of a new generation of ADAS applications, which challengingly combine different functions, sensors, actuators, hardware platforms, and Human Machine Interfaces (HMI). This book presents the different results of the DESERVE project concerning the ADAS development platform, test case functions, and validation and evaluation of different approaches. The reader is invited to substantiate the content of this book with the deliverables published during the DESERVE project. Technical topics discussed in this book include:Modern ADAS development platforms;Design space exploration;Driving modelling;Video-based and Radar-based ADAS functions;HMI for ADAS;Vehicle-hardware-in-the-loop validation system

Study for identification of beneficial uses of space, phase 1. Volume 2, book 1: Technical report, introduction, methodology, results

A study was conducted to determine the beneficial uses of space and to identify the products, processes, or services that will be best developed or produced in the unique environment offered by spacecraft. The subjects discussed are: (1) review of study background, (2) specific users and uses, (3) methodology, and (4) basic data generated and significant results