The realm of planetary exploration is gravitating towards a smaller class of rover. These microrovers are technically and scientifically ambitious and offer high return on investment. With mission resource constraints...
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The realm of planetary exploration is gravitating towards a smaller class of rover. These microrovers are technically and scientifically ambitious and offer high return on investment. With mission resource constraints and limited mass, size, power, and communications, these rovers must leverage light-weight yet robust power systems which enable autonomous exploration initiatives, environmental survivability, fault detection, isolation, recovery, and ultimately mission success. This paper presents methodology, design, analysis and results pertaining to the power system of MoonRanger, the first lunar microrover for measuring ice at the Moon's south pole on a NASA Commercial Lunar Payload Services (CLPS) mission. Radioisotope Thermoelectric Generator (RTG) power that pertains to large rovers is not viable for microrovers due to mass, budget and availability. Instead, the rover is equipped with a custom designed solar panel with 30.7% cell efficiency able to sustain the rover's battery system for a full lunar day. Coupled with 200 Wh of lithium ion battery power, the rover's power system supports autonomous exploration into darkness for up to 4 hrs of dark survival. This custom power system is a fraction of the mass and cost of a traditional rover. Power generated by the solar panel is distributed to the rest of the rover system via compartmentalized power switching groups. This compartmentalization improves fault isolation for the rover's on-board fault detection and mitigation system as well as for operators on Earth. For missions with lower budget and time, like MoonRanger, rigorous testing and purchasing of space-rated parts is not as feasible. This power system organization can also be used to isolate the various power switching groups allowing for simpler testing, integration, and operational mode configuration. This paper describes how the rover's solar panel attributes, power generation, analysis, distribution, and storage systems facilitate MoonRanger's ambitio
This paper proposes a robust fractional-order sliding mode control of a3-DOF robot system driven by DC ***,a conventional sliding mode controller based on PDα sliding surface is *** simulations have been carried out ...
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This paper proposes a robust fractional-order sliding mode control of a3-DOF robot system driven by DC ***,a conventional sliding mode controller based on PDα sliding surface is *** simulations have been carried out to show the proposed control system's robustness properties as well ascompare
— The development of robotic systems for palletization in logistics scenarios is of paramount importance, addressing critical efficiency and precision demands in supply chain management. This paper investigates the a...
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The question of whether undergraduate engineering students can provide meaningful support to a university's research program is not unusual. Undergraduate engineering students often have limited technical experien...
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The question of whether undergraduate engineering students can provide meaningful support to a university's research program is not unusual. Undergraduate engineering students often have limited technical experience, and sometimes have yet to complete even basic academic courses required to fully understand the research activities involved. This paper evaluates, assesses and reviews the feasibility, benefits, value and contributions of undergraduate engineering students in a major fuel cell system research study at Lawrence Technological University. In the spring of 2006 Lawrence Technological University (LTU) entered into a fuel cell research program with the US Army Tank-Automotive Research, Development and engineering Center (TARDEC), in Warren, Michigan. The objectives of the research work were to build a fuel cell test stand, install a hydrogen gas tank supply system, and to test two 1.2 kW polymer electrolyte membrane (PEM) fuel cells to assess their performance, durability and reliability over a wide variety of operational and environmental conditions over a sixteen month period. In order to successfully accomplish this work nine student research assistants over the course of the program were required. All of these research student assistants were undergraduate engineering students from LTU's mechanical and Electrical engineeringprograms, with the exception of one who was an international graduate student in the LTU Master of Science in Automotive engineeringprogram. This paper provides a review of the process utilized to hire and direct these student's work efforts, and gives a detailed description of their contributions and accomplishments. AU of the major research objectives for the program were achieved. We have found that students benefited not only from the engineering and technical understanding derived from such participation, but also in the soft-science areas of teamwork, time management, and multi-disciplinary activities. Detailed assessment data
Within the EC project Copernicus SADTS (Semi-Active Damping of Truck’s Suspension and Its Influence on Driver and Road Loads) the semi-active suspension for Liaz truck prototype is being developed. The objective is t...
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Within the EC project Copernicus SADTS (Semi-Active Damping of Truck’s Suspension and Its Influence on Driver and Road Loads) the semi-active suspension for Liaz truck prototype is being developed. The objective is to decrease the dynamic road-tyre forces in order to reduce the road damage. It was necessary to develop a suitable truck prototype, its simulation model, different control concepts and to implement the semi-active suspension. The paper describes the development stages and the so far achieved results. The full mathematical model was the basis for simplified models for control designs and served as a reference model for comparison of different control concepts. The spatial three dimensional simulation model has been developed and verified. The base model includes also the reference inputs of excitation and the different criteria for performance evaluation. The purpose of the model was to investigate the vertical dynamics though with the influence of antisymmetry of uneveness and lateral motion. A number of different control concepts have been considered. Possible suitable control concepts have been selected from existing classical as well as advanced control design methods. Also several within this project newly developed approaches have been added. There have been considered the control concepts of simple approaches (sky hook), classical approaches (LQR), multi-objective multi-parameter optimization (ΜΟΡΟ), fuzzy and neural networks, robust control design. The newly developed control concepts are ground-hook and combination sky/ground-hook, robust multi-objective optimization based on Taguchi approach, fuzzy control based on optimization, structural approach (separate control of frame and cabine suspension). The performance criteria for evaluation have been road forces, driver’s seat and load accelerations, robustness against change of parameters. The comparison has been done on the simulation model in SIMPACK program package connected with MAT-LAB/SIMULI
In minimally invasive surgery (MIS), controlling the endoscope view is crucial for the operation. Many robotic endoscope holders were developed aiming to address this prob-lem,. These systems rely on joystick, foot pe...
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Dye Sensitize Solar Cell (DSSC) gained attention as a replacement for silicon solar cells owing to operational and economic benefits. This study aims to synthesize the Fe2O3/ZnO composites using two different methods;...
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Volitional use of the paretic upper-extremity after hemiparetic stroke is necessary for positive functional and neurological improvement. Unfortunately, much of the recovery process occurs outside of the purview of th...
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To create a hydrophilic, lubricious, more wear-resistant UHMWPE bearing, a novel hyaluronan (HA) derivative and novel UHMWPE-hyaluronan composite were developed. HA was silylated to increase its hydrophobicity and com...
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To create a hydrophilic, lubricious, more wear-resistant UHMWPE bearing, a novel hyaluronan (HA) derivative and novel UHMWPE-hyaluronan composite were developed. HA was silylated to increase its hydrophobicity and compatibility with UHMWPE. The silyl HA rapidly diffused into the connected pores of UHMWPE preforms in xylenes solution, and fixed within UHMWPE and on its surface after crosslinking. A micro-composite was obtained after hot-pressing the porous preform. The presence of HA film on the composite surface has been demonstrated through X-Ray photoelectron spectroscopy (XPS) analysis and Toluidine Blue O (TBO) dye assay. The aqueous contact angles of micro-composite samples were significantly lower compared with UHMWPE control samples, and the samples processed with hydrolysis prior to final molding were superior to those processed with hydrolysis after molding.
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