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Proceedings of the 2011 ACM Symposium on Applied Computing

作者： Ulbrich, Peter Kapitza, Rüdiger Harkort, Christian Schmid, Reiner Schröder-Preikschat, Wolfgang Department of Distributed Systems and Operating Systems Friedrich-Alexander University Erlangen-Nuremberg Germany Department of Automation Control Friedrich-Alexander University Erlangen-Nuremberg Germany Siemens Corporate Technology Munich Germany

ISBN: (纸本)9781450301138

Quadrotor helicopters are micro air vehicles with vertical take-off and landing capabilities controlled by varying the rotation speed of four fixed pitch propellers. Due to their rather simple mechanical design they have grown to popularity as platform for various research projects. Despite most of them being individually highly successful, they are typically tailored to a specific purpose making it hard to utilise them for further research and education. In this paper, we present the novel design of the I4Copter quadrotor. It has been developed to provide a stable demonstration quadrotor platform for various kinds of research and education projects targeting cross-field challenges in real-time and embedded systems, distributed systems, robotics and cybernetics. The modular and open architecture of our platform allows an application- specific, fine-grained extension, adaption and replacement of software and hardware components. The safe extensibility is supported by strict temporal and spatial isolation between the software modules. We validated our approach by two distinct cross-field use cases: an evaluation platform for modularised control algorithms enabling trajectory tracking and an implementation that is resilient to transient hardware errors. © 2011 ACM.

关键词： Embedded systems

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Time-Optimal Attitude Maneuver for Underactuated Spacecraft based on Pseudospectral Method

Time-Optimal Attitude Maneuver for Underactuated Spacecraft ...

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2014中国制导、导航与控制学术会议

作者： Dongxia Wang Jinxian Zhao Caibo Hu Department of Operating Control and Technology Beijing Satellite Navigation CenterBeijing100094China

ISBN: (纸本)9781479946983

the time-optimal attitude maneuver problem of a rigid spacecraft with only two control torques along its principal axes is studied using Radau Pseudospectral Method (RPM).The asymmetric and symmetric spacecraft have been considered in ***,we establish the attitude dynamical models of asymmetric and symmetric spacecraft with two controls,and use (w,z) parameter to describe the attitude ***,according to the general optimal control problem like Bloza form,the maneuver time minimum as the performance index is selected to be optimized,simultaneously considered the control inputs and angular velocities boundary in the practical application of ***,the optimal maneuver problem is discretized based on the Radau Pseudospectral Method and then converted into a nonlinear programming *** for asymmetric and symmetric system are carried out based on GPOPS toolbox and the analysis results illustrate the feasibility the proposed algorithm.

关键词： angular velocity control attitude control motion control nonlinear programming optimal control space vehicles torque control Bloza form GPOPS toolbox RPM Radau pseudospectral method angular velocities boundary asymmetric spacecraft attitude dynamical models attitude motion control torques maneuver time nonlinear programming problem optimal control problem performance index rigid spacecraft symmetric spacecraft time-optimal attitude maneuver problem underactuated spacecraft Actuators Angular velocity Attitude control Interpolation Optimal control Polynomials Space vehicles Space vehicles attitude control Optimal control Rigid spacecraft Torque control angular velocity control performance indicators ANGULAR VELOCITY revolutions per minute Attitude maneuvers Nonlinear Programming Motor control actuators Polynomial Interpolation

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Oxygen Sensor Based on the Principle of Electrochemical Pump

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Science China Mathematics 1994年第3期37卷 379-384页

作者：罗瑞贤刘恩辉任凤彩陈霭璠 Applied Chemistry Department Beijing Institute of Chemical TechnologyBeijing 100029PRC Applied Chemistry Department Beijing Institute of Chemical TechnologyBeijing 100029PRC high-temperature oxygen sensor of limiting.current with a porous layer on the cathode te limit the diffusion rate of oxygen is investigated and fabricated.The solid electrolyte is made of Yttria-doped stabilized zirooma (YSZ) and the porous platinum film electrode is deposited on the surface of YSZ.The relation between temperature and oxygen concentration is tested at 629°-780℃ in a mixture of N2 and O2 with the oxygen concentration being 0-37%.Experimental results show a linear output with the oxygen concentration.The temperature-dependence of its output can be explained by taking into account a mixed diffusion control mechanism of the ordinary and Knudsen diffusion.The operating principlestructure and performance of the sensor are discussed.

A high-temperature oxygen sensor of *** with a porous layer on the cathode te limit the diffusion rate of oxygen is investigated and *** solid electrolyte is made of Yttria-doped stabilized zirooma (YSZ) and the porous platinum film electrode is deposited on the surface of *** relation between temperature and oxygen concentration is tested at 629°-780℃ in a mixture of N2 and O2 with the oxygen concentration being 0-37%.Experimental results show a linear output with the oxygen *** temperature-dependence of its output can be explained by taking into account a mixed diffusion control mechanism of the ordinary and Knudsen *** operating principle,structure and performance of the sensor are discussed.

关键词： oxygen sensor limiting current diffusion control

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HUB SIZE SELECTION CRITERIA FOR controlLABLE PITCH PROPELLERS AS A MEANS TO ENSURE SYSTEMS INTEGRITY

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NAVAL ENGINEERS JOURNAL 1978年第6期90卷 49-61页

作者： WIND, J The Authoris a citizen of the Netherlands. He studied Aircraft Engineering and Mechanical Engineering at the Delft Institute of Technology from which he received his MS degree in 1955. He began his career as a Research Engineer in the field of Nuclear Engineering employed by VMF—Stork and he holds several U.S. Patents relating to ultra—centrifuges for the separation of Uranium. He was next engaged. in design of control gear for radio astronomy aerials and operating gear for bridges and huge floodgates in the Scheldt and Rhine Delta. Later he became involved in the control of diesel engines and controllable pitch propellers and in 1967 joined LIPS Propeller Works where he developed CP propeller mechanisms solved the problem of high—pressure oil supply to large diameter marine shafts and made an improvement for high—speed propeller nozzles. As Head of the Design Department he was responsible for the design of large controllable pitch propellers for fast Container Ships and Naval Ships with gas turbine drive. Mr. Wind has authored several technical publications among which are “Controllable Pitch Propellers. Their Principles and Mechanisms” and “The Development of CP Propeller Systems.” At the present time he is a Corporate Engineering Consultant to the Propeller Division of LIPS B. V.

In a CP propeller the size of the hub largely influences the reliability of the system in operation. Accurate choice of the hub—size provides the best means to prevent the system from structural propeller failures and is therefore the best method to ensure reliability and optimized performance. Recent failures of high—power CP propellers, of which one Navy propeller had a serious mission failure, could have been avoided if a larger hub had been adopted. The paper contains two tools, available also to nonspecialists. One allows clear recognition of the technical degree of difficulty of all types of propellers and the other is a scale to determine the degree of load of each CP propeller hub. Information is given concerning the influence of the hub/diameter ratio on the hydrodynamic performance.

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COMMERCIAL APPLICATIONS OF ADVANCED MARINE VEHICLES FOR EXPRESS SHIPPING

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NAVAL ENGINEERS JOURNAL 1983年第3期95卷 283-300页

作者： LUEDEKE, G FARNHAM, RB JR. George Luedeke Jr.: received his BS degree in Mechanical Engineering from Massachusetts Institute of Technology and his MS degree in Product Design from Illinois Institute of Technology. Early in his career Mr. Luedeke joined General Motors Corporation as a designer responsible for development of people mover and rail rapid transit systems. From 1964 to 1974 he was with Hughes Aircraft Company. At Hughes he performed analyses and developed designs for a wide variety of program and proposal efforts such as: High Speed Ground Transportation (DOT) Task Force Command Center (NAVY) Panama Canal Marine Traffic Control Center (Panama Canal Co.) Royal Iranian Navy Command Center (Iran) Tactical Information Processing and Interpretation Center (Air Force) and WALLEYE CONDOR and PHOENIX Missile Systems (NAVY). He also had marketing development responsibilities related to the diversification of Hughes resources in civil business areas such as: Automatic train control (WMATA BARTD SCRTD) water/sewage treatment plant automation (Santa Clara County) Aqueduct Control (SWR) Hydrometeorological data collection (BPA WMO) and Salton Sea basin systems analysis (Dept. of the Interior). He was responsible for combat system integration for the Hughes 2000T Surface Effect Ship (SES) proposal. He also conducted detailed studies concerning ship flexure for the Improved Point Defense Target Acquisition System Program and for the definition of operational High Energy Laser weapon installations on a series of conventional monohulls (DLG DD and CVN). Since 1974 Mr. Luedeke has been employed at RMI Inc. (formerly Rohr Marine Inc.). During this time he has held several positions. His responsibilities have included directing a number of studies on advanced SES concepts managing activities defining mission/cost effectiveness of military and commercial SES's including defining the operational benefits and enhanced survivability characteristics of cargo SES's for high speed military sealiftfor NA TO and Southeast Asia

This paper will present the results of a marketing, engineering, and economic analysis of advanced marine vehicles done by IMA Resources, Inc. and RMI, Inc., in support of a Maritime Administration project to study “Multimode Express Shipping”. The study was conducted in 1981 and examined the economic benefits of using advanced marine vehicles as express cargo vessels in domestic and international service. Commodity characteristics, desirable express carrier rates, and potential high payoff service and route alternatives were identified. Advanced marine vehicles were surveyed and sized to meet desirable deadweight and block speed objectives. The costs of operating these craft on a variety of trade routes were calculated using an advanced marine vehicle economic analysis program. Revenues, expenses, break-even, profit and loss, cash flow requirements, tax summary and economic indicators (i.e., cost/ton – mile, etc.) were projected over the expected life of the vehicles as was return on investment. Traffic density and market penetration considerations narrowed the field of choice to smaller sized advanced marine vehicle carriers (i.e., 50 and 250 ton deadweight) and to three international and five domestic routes.

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A Fine Excision ATLS Manual No Longer Defines Trauma as a Surgical Disease

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ANNALS OF EMERGENCY MEDICINE 2010年第3期55卷 20A-24A页

作者： Millard, William B. The new 8th edition of the Advanced Trauma Life Support (ATLS) course manual contains a small but significant change. The phrase “trauma is a surgical disease” long a point of contention with other specialties caring for trauma patients has been removed. Now used in over 50 countries as the basis for training in the initial assessment and management of trauma this publication reflects the research and clinical experience of the American College of Surgeons (ACS) Committee on Trauma and expresses that organization's philosophy toward triage diagnosis and clinical care. Astute readers of the ATLS materials have noticed that a certain message is conspicuous by its absence. The preface to the 7th edition of the ATLS describes the ACS's role as follows: In accordance with that role and recognizing that trauma is a surgical disease the ACS Committee on Trauma (COT) has worked to establish guidelines for the care of the trauma patient. The 8th edition includes a substantially similar sentence minus the crucial phrase on trauma as a “surgical disease.” John B. Kortbeek MD FACS professor of surgery and critical care at the University of Alberta and a member of the COT who was instrumental in the revision process for the manual confirms that the deletion is intentional. Dr. Kortbeek explains the change in historical terms. “The intent of making that statement” he says “was to emphasize that to have a successful trauma system and a successful trauma hospital surgeons needed to be included in the management team and the care of the trauma patient. That remains true today. What changed over time is that that statement became a focal point and could be interpreted in varying ways including in a negative exclusive way suggesting that only surgeons should be managing trauma patients which is not correct and never was the intent of the statement.” The ATLS he says presents a “common language” for a safe and effective response to trauma not a mandatory formula. Harmonious relations among the various spe

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