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In this paper, a model predictive control (MPC) based trajectory tracking scheme utilizing steering wheel and braking or acceleration pedal is proposed for intelligent vehicles. The control objective is to track a desired trajectory which is obtained from the trajectory planner. The proposed control is based on a simplified third-order vehicle model, which consists of longitudinal vehicle dynamics along with a commonly used bicycle model. A nonlinear model predictive control (NMPC) is adopted in order to follow a given path by controlling front steering, braking and traction, while fulfilling various physical and design constraints. In order to reduce the computational burden, the NMPC is converted to a linear time-varying (LTV) MPC based on successive online linearization of the nonlinear system model. Two different test conditions have been used to verify the effectiveness of the proposed approaches through simulations using Matlab and CarSim.

This paper presents a parametric, experimental study of the performance of gas and liquid propane injection in a spark ignition, multi-point port injected (MPI) engine. An inline, six cylinder engine is used over a wide range of speeds and torques, and the air/fuel ratio, compression ratio and injection timing are all varied. The engine was mapped at the standard compression ratio of 9.65:1 with the original, gasoline MPI system, propane gas MPI, and single point, throttle body, propane gas injection. Gas and liquid propane MPI are then tested at a compression ratio of 11.7:1. Contour plots of thermodynamic efficiency and the specific emissions of HC, NOx, CO2 and CO over the torque/speed range are presented and compared. The results show significant differences in performance between gas and liquid propane MPI injection, as well as the MPI and throttle body gas injection.

The Mini Pressurised Logistics Module (MPLM) has the important job of servicing the Space Station via the National Space Transportation System (NSTS). During the previous and the on-going Alenia design activities, a continous effort is spent to optimize the MPLM performance characteristics with a possible mass reduction. The aim is to reach the best compromise between different needs: the payload requirements, the functional ground and flight operational constraints (three units qualified for 25 flight missions each), the total mass available for the payload. This paper has the objective to document the recent configuration changes and activities of the last couple of years. The two subsystems involved in this evolution are the Thermal Control (TCS) and the Environmental Control (ECLSS). Most of the MPLM equipment has already passed the Critical Design Review (CDR) step and the update situation for each piece of equipment is listed in this paper.

The Active MPLM system verification spans multiple programs and multiple organizations with multiple interfaces (Shuttle, ISS, MPLM, MELFI); the MPLM CIWG (Cooling Integration Working Group) was formed to provide a forum for working Active MPLM integration issues such as reviewing the interface verifications currently in plan, identifying the remaining risks to first time use of the end-to-end system, and identifying and working to resolve integrated issues with the system. The purpose of the Unique TCS Testing is to assess the system capability to calibrate the MPLM/Orbiter cooling loop to minimize the risk of inaccurate MPLM flow rate control to the Minus Eighty–degree Laboratory Freezer for the ISS (MELFI), to perform flow characterization testing for all racks location to minimize risk of R/F rack underflow, and to assess loop flow rate control under reduced flow condition to verify system stability.

The Mini Pressurised Logistic Module (MPLM) includes an Environmental Control and Life Support System (ECLSS), whose general purpose is to guarantee a comfortable environment for the Crew. In particular, among the functions of the ECLSS, there is the provision of a correct ventilation in the habitable area of the Module and an air flow adequate to support fire detection in powered zones. These tasks are carried out by an air ventilation system mainly composed of a fan, eight cabin diffusers and a ducting system. In addition, the ECLSS furnishes, through a dedicated distribution system, the capability to suppress fire by release of the Carbon Dioxide contained in a portable fire extinguisher.

The MPLM (Mini Pressurized Logistic Module) is one of the Elements constituting the ISSA (International Space Station Alpha). With respect to the other Elements, the MPLM is not permanently attached to the ISSA, but it is transported by the Orbiter several times from/to the Earth, since its primary use is to resupply and return cargos. The MPLM capability to support the logistic flights is guaranteed during several mission phases (ground, Orbiter transportation, on-orbit docked to the Station). Since the installed cargo can be passive or active, the required MPLM functions are based on the actual flight. This paper presents an overview of the activities performed in Alenia Spazio to identify the criticality and peculiarity of the MPLM mission scenarios from the thermal point of view. The best technical solutions, foreseen up to now, have been implemented in the design to guarantee the reliability requested by such an important and unique Space Station Element.

The Total Off-gassing test purpose is to determine the identity and quantity of trace gas contaminants offgassed in areas of spacecraft where the crew will breathe the atmosphere. Two different air sampling methods were adopted in parallel during the off-gassing tests on the Multi-Purpose Logistics Modules (MPLM) by Alenia Spazio. The first method, based on NASA (National Aeronautics and Space Administration) requirements, foresees storage of collected air samples into stainless steel pressure cylinders. The second method proposed by ESA (European Space Agency), uses trace contaminants adsorption on Carbopack™ filled ceramic tubes. Sample lines route the samples collected inside the MPLM cabin, to the respective external collection points. Successively, the stored samples are chemically analyzed by Gas Chromatography / Mass Spectrometry (GC/MS) techniques and the module offgassing rates are calculated.

Solar powered UAV mainly relies on solar energy for range, it uses photovoltaic cells to convert solar radiant energy into electric energy for the use of solar powered UAV energy system. In response to the issue of solar powered UAV photovoltaic power supply energy utilization efficiency, an intelligent sliding mode based MPPT control method is proposed to maximize the output power of photovoltaic power supply. Firstly, introduce and analyze the photovoltaic cell model and its output characteristics; Secondly, the DC/DC converter and its MPPT control technology are introduced. Traditional MPPT control methods such as perturbation and observation and incremental conductance have poor adaptability to external environmental changes, the intelligent algorithm has the characteristics of fast rate of convergence and global search, etc.

The development of a unique micro quenched age formed (MQAF) process for producing titanium alloys of shallow hardening composition with deep hardening characteristics is described. Also, in line with the desire to improve the elevated temperature strength of titanium alloys, an alternate approach has been devised for producing titanium alloys with useful strength above 1000 F. Data are presented on the development of composites of two titanium alloys, each constituent possessing complementary properties. It is believed that this bi-alloy concept offers great potential for titanium alloys in the high-temperature range.

The use of a magneto-rheological (MR) fluid brake as a semi-active torsional damper has been investigated. The MR fluid brake can be used as a clutch-type mechanism to transmit torque between a rotating shaft and the brake housing. In that fashion, the MR brake can be used as an adaptive friction damper. This preliminary effort presents the results of experimental testing of an MR brake and its implementation as a variable friction damper on a simple single degree of freedom torsional system. Optimum friction levels are predicted based on established tuning rules. The experimental work verifies the optimality of the tuning for the case of fixed friction dampers and indicates the potential for future application of an MR brake in the control of torsional vibration.

The task of evaluating and designing space gloves requires accurate biomechanical characterization of the hand. The availability of magnetic resonance (MR) imaging has created new opportunities for in vivo analysis of physiological phenomena such as the relationship between circulation and fatigue. An MR imaging technique originally proposed to quantitatively evaluate cerebral perfusion has been modified to evaluate the capillary microcirculation in hand muscles. An experimental protocol was developed to acquire perfusion-weighted images in the hand before and after various levels of exercise. Preliminary results on the feasibility of applying the MR imaging technique to the study of microcirculation and fatigue in the hand are presented. The potential of this method for space glove testing and design is also discussed.

The SAE J300 classification was expanded to 0W-12 and 0W-8 viscosity grades in 2015, and lower viscosity engine oils have been studied in the industry. ILSAC GF-6B that will be introduced in 2020 will specify a 0W-16 requirement, but 0W-12 and 0W-8 grades are not considered. Because engine oil equal to or higher than the 0W-20 grade is recommended for almost all engines globally, suitable engine tests for 0W-12 and 0W-8 do not exist. Therefore, the Japan Automobile Manufacturers Association, Petroleum Association of Japan and Society of Automotive Engineers of Japan decided to establish new 0W-12 and 0W-8 low viscosity engine oil specifications. It is referred to as JASO GLV-1, and together with a new fuel economy engine test procedure, these engine oils for better fuel economy will be put on the Japanese market in 2019. Motoring friction torque tests are widely used to ascertain the friction reduction effect of fuel-economy engine oils.

Milliken Research Associates has developed a new simulation tool, named Vehicle Dynamics Simulation-Matlab/Simulink (VD-M/S). Produced for the government's Variable Dynamic Testbed Vehicle (VDTV), VD-M/S is an 18 degree-of-freedom simulation programmed in the Matlab/Simulink environment. It contains a detailed non-linear tire model, kinematic and compliance effects, aerodynamic loadings, etc. as do MRA's other simulation programs. Unique to VD-M/S is its development from Day One as a simulation catered to the inclusion and exploration of active systems within the vehicle.

Traditional vector control needs the installation of mechanical sensors to gather rotor position and speed information in order to enhance the control performance and dynamic quality of electric vehicle wheel motors, which increases system cost and reduces system reliability and stability. On the basis of Popov's super-stability theory, an appropriate adjustable model and reference model are constructed, and the system's reference adaptive law is determined. Furthermore, to solve the problem of the standard PI regulator's poor anti-interference capabilities in speed controllers, the approach of utilizing a sliding-mode speed controller in the speed loop is presented. Finally, a MATLAB/SIMULINK simulation model is created to simulate the motor in three scenarios: no-load start, abrupt speed change, and sudden load change, and a permanent magnet synchronous motor experimental platform is created to validate the control approach.

A high-accuracy automotive rotation sensor with high-sensitivity has been developed using a ferro-magnetic resistance element, called MRE, which we have recently developed. This sensor composed of MRE and a multi-pole magnet, is a compact, environmental-resistive, low rpm detectable device with high hybrid circuit density including an electric signal processing circuit. The new sensor is especially designed for generating a double-frequency output to ensure a duty ratio for precise detection of rotation. The sensor is now used as a vehicle speed sensor capable of measuring from low rpm to high rpm, mounted directly onto the transmission. The sensor is not only considered to be a riable alternative to the conventional rotation sensor, but will be used in an expanding number of applications.

We have developed a non-contact position sensor to obtain linear output using a ferro-magnetic magneto-resistance element (MRE) with good characteristics of endurance and extremely high sensitivity to low magnetic fields. This position sensor consists of a MRE and a rectangular magnet. It has an extremely stable and linear output, and good endurance to the environment, using saturated magnetic field characteristics of MRE. This non-contact position sensor has wide industrial applications and can be used for automotive parts.

Bosch/UAES has developed a low cost EMS special for small gasoline engines. The article will introduce this system from view of components design and system design. In components design part special component design for small gasoline engine to reduce cost is described. To reduce cost a special low end ECU and fuel deliver system has been designed, other low-end components are chosen into the system. Features of the components are described. In system design part the requirement of system design is described. To reduce cost normal components configuration should be redesigned. Special design and consideration of load detection, engine speed detection, system components configuration and optional solutions is expressed. For load detection, both P-system and alpha/n system is introduced. For engine speed detection both segment and increment system is introduced. System components configuration for low cost EMS is introduced and feasibility is explained.

This paper analyzes MSG-3 FROM A MANUFACTURER'S PERSPECTIVE and addresses the question: Was it effective? The experience and insights gained from being the first manufacturer in the world to use MSG-3 to develop a scheduled maintenance program for an entire airplane is discussed. Application of MSG-3 to both the 757 & 767 revealed several areas of deficiency which are analyzed as well as the methods used to “work around” them. This discussion of the problem areas is followed by an analysis of the overall effectiveness of MSG-3. A new decision diagram is illustrated and explained which should be considered in developing MSG-4.

When a new aircraft is introduced into airline service, it must have a maintenance and inspection program approved by the Federal Aviation Administration (FAA). The “Airline/Manufacturer Maintenance Program Planning Document,” commonly known as MSG-3, is a method used (by the airlines and manufacturers) to develop the necessary maintenance/inspection program. The FAA participates with the manufacturer and airlines in the development of the program and finally, the FAA Maintenance Review Board (MRB) reviews the program, accepts it, and publishes it in an MRB report. This process is started early in the development of the new aircraft, well before the first flight, and concluded prior to delivery of the first aircraft.