Improving Energy Efficiency and Motion Control in Load-Carrying Applications using Self-Contained Cylinders

Because of an increasing focus on environmental impact, including CO2 emissions and fluid spill pollution, inefficient hydraulic systems are being replaced by more environmentally friendly alternatives in several industries. For instance, in some offshore applications that have multiple diesel generators continuously running to produce electricity, all hydraulic rotating actuators supplied from a central hydraulic power unit have been replaced with AC induction motors containing a variable frequency drive and gearbox. However, hydraulic linear actuators are still needed in most load-carrying applications mainly because of their high reliability associated with external impact shocks. Moreover, their force capacity is higher than that of their linear electromechanical counterparts. Valve-controlled linear actuators (cylinders) supplied from a centralized hydraulic power unit are standard in offshore load-carrying applications. In addition to the advantages mentioned above of hydraulic linear actuators, they have, nevertheless, a number of important drawbacks, which include: 1) a high level of energy consumption due to significant power losses caused by flow throttling in both the pipelines and valves, 2) reduced motion performance due to the influence of load-holding valves, 3) high CO2 emissions and fuel costs related to the diesel generator that supplies electricity to the hydraulic power unit, 4) significant potential for hydraulic fluid leakage because of many leakage points, 5) demanding efforts with respect to installation and maintenance, as well as 6) costly piping due to the centralized hydraulic power supply. The work presented in this dissertation and the appended papers are devoted to replacing inefficient hydraulic linear actuation systems traditionally used in offshore load-carrying applications with more environmentally friendly solutions. Two alternative technologies are identified, namely electro-mechanical and electro-hydraulic self-contained cylinders. The feasibility of replacing conventional valve-controlled cylinders with self-contained cylinder concepts is investigated in two relevant case studies.publishedVersio

ME-EM 2007 Annual Report

Table of Contents Research Expansion Research Groups Faculty & Staff Students Alumni Resources Graduates Publicationshttps://digitalcommons.mtu.edu/mechanical-annualreports/1011/thumbnail.jp

Hand gesture-based virtual reality training simulator for collaboration rescue of a railway accident.

Training simulator is an efficient and innovative tool to help users learn professional skills due to its convenience and safety. However, complex human-computer interaction is one of the main disadvantages that limits its effectiveness in safety training, especially for the rescue of a railway accident which requires collaborations. Through designing a set of task-specific hand gestures, we developed a training simulator for the recovery of a railway accident which helps the rescuers learn and practise rescue skills in a life-like environment and gain the firsthand experience. To test the validity of our training simulator, a user experiment is designed to compare it with the controller-based simulator in a between-groups study with 51 participants, focusing on different aspects of effectiveness. The results demonstrate that the hand gesture-based controller can be more efficient and usable to deal with complex interactions than the traditional hand-held controller

Risk Assessment as a Tool for Mobile Plant Operators for Sustainable Development: Lessons from the Western Australian Mining Industry

Mobile plant is used extensively not only in the Western Australian (WA) Mining Industry but internationally as well. The use of mobile plant has inherently high risk and every year is associated with a significant number of workplace fatalities and injuries. Prior to this research being conducted there was no specific data published related to mobile plants incidents and fatalities for the Western Australian mining industries. The aim of this research was to improve the safety performance of mobile plant operators in the Western Australia (WA) mining industry by identifying the causes of mobile plant incidents reported to Resources Safety between 1/1/2007 and 31/3/2020

The Bicycle in Western Literature: Transformations on Two Wheels

Since the invention of the modern bicycle in the 1880s, bicycles have played an integral role in western culture. As a reflection of its cultural significance and impact on individuals, many novelists have incorporated bicycles into their works in both realistic and symbolic ways. This paper focuses on the use of bicycles in western literature from the bicycle boom decade of the 1890s to the mid-twentieth century and includes works of H. G. Wells, Émile Zola, Arthur Conan Doyle, Dorothy Richardson, D. H. Lawrence, Ernest Hemingway, F. Scott Fitzgerald, Simone de Beauvoir, Samuel Becket, Luigi Bartolini and L. P. Hartley. These novelists used bicycles not merely as a means to transport characters, but as catalysts for or symbols of social and personal transformation. Novels written around the turn of the twentieth century reflect the significant positive role bicycles played in the cultural changes and personal freedom of this era. Later, after the first World War and the advent of the automobile, bicycles remained literary devices, but their symbolic use changed. While in the post-World War I era bicycles are still capable of transforming characters, their transformational potential is often unrealized or is tempered by skepticism or pessimism

A Framework for Life Cycle Cost Estimation of a Product Family at the Early Stage of Product Development

A cost estimation method is required to estimate the life cycle cost of a product family at the early stage of product development in order to evaluate the product family design. There are difficulties with existing cost estimation techniques in estimating the life cycle cost for a product family at the early stage of product development. This paper proposes a framework that combines a knowledge based system and an activity based costing techniques in estimating the life cycle cost of a product family at the early stage of product development. The inputs of the framework are the product family structure and its sub function. The output of the framework is the life cycle cost of a product family that consists of all costs at each product family level and the costs of each product life cycle stage. The proposed framework provides a life cycle cost estimation tool for a product family at the early stage of product development using high level information as its input. The framework makes it possible to estimate the life cycle cost of various product family that use any types of product structure. It provides detailed information related to the activity and resource costs of both parts and products that can assist the designer in analyzing the cost of the product family design. In addition, it can reduce the required amount of information and time to construct the cost estimation system

NASA space station automation: AI-based technology review

Research and Development projects in automation for the Space Station are discussed. Artificial Intelligence (AI) based automation technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics. AI technology will also be developed for the servicing of satellites at the Space Station, system monitoring and diagnosis, space manufacturing, and the assembly of large space structures