Refine Your Search


Search Results

Viewing 1 to 17 of 17
Technical Paper

Effectiveness Considerations in Applying AFSCM 375-5 Requirements to Control and Surveillance Systems

This paper discusses general and specific requirements of AFSCM 375-5 as applied to control and surveillance systems. The ingredients of the total design concept to achieve operational effectiveness includes specifications, analyses, engineering reviews, and tests. The concepts of utility, acquisition time, effectiveness, and cost are discussed. Model and trade-off considerations are presented. Applications of WSEIAC and AFSCM 375-5 principles and procedures to three complex electronic systems are illustrated.
Technical Paper

Intelligent Damage Adaptive Control for Commercial Air Transports

In situations of unanticipated maneuvers of an aircraft, information must be immediately received by the aircrew for correcting the aircraft flight path to a safe trajectory for continued flight and landing. These maneuvers may be due to failures in the control system, wind gust upsets, or other off-nominal conditions. Also critical are situations of control maneuvers that exceed the normal flight envelope of the aircraft, and providing information to the pilot and control system that will result in safe return to controllable flight. The Intelligent Damage Adaptive Control System (IDACS) operates during flight to detect dangerous conditions of the aircraft and to provide the crew with assistance to restore and to maintain safe control. This system is being developed by Boeing for NASA.
Technical Paper

Technical Leadership Challenges for Highly Automated Driving: Technology Leadership Brief

Driver assistance features have been introduced to the market focusing on basic, independent functional scenarios. The trend is showing that these kinds of products are facing more and more complex scenarios and we are transitioning from single independent functions to a strongly networked system. Some of the drivers for future autonomous vehicles are 360° monitoring by active safety technology and V2X (vehicle to vehicle or vehicle to infrastructure) communication. In the past vehicles were strictly operated by the driver. Advanced driver assistance products added so called feedback features like lane departure warning, forward collision warning, and blind spot monitoring. First steps towards semi-autonomous driving started with the development of active support functions like adaptive cruise control or lane keeping support. Collision mitigation with various authority levels is the next milestone towards automation followed by other, even more advanced, features.
Technical Paper

Integrated Health Monitoring and Fault Adaptive Control for an Unmanned Hexrotor Helicopter

This paper presents a novel health monitoring and fault adaptive control architecture for an unmanned hexrotor helicopter. The technologies developed to achieve the described level of robust fault contingency management include; 1.) A Particle Swarm Optimization (PSO) routine for maximizing the “built-in” fault tolerance that the closed loop flight control system affords, 2.) A two-stage Kalman filter scheme for real-time identification of faults that are masked by control system compensation, and 3.) A reconfigurable control allocation method which compensates for large degradations of the six main motor/rotor assemblies. The fault adaptive control system presented herein has strong robustness against small faults without the need for controller reconfiguration, and strong tolerance of large faults through adaptive accommodation of the fault source and severity.
Technical Paper

Crew Life Support System for Interplanetary Vechicles

Interplanetary manned missions will change significantly the requirements imposed upon Life Support Systems (LSS) and specifically the requirements on LSS Automated Control Systems (ACS). During interplanetary manned missions the possibilities to control the operation of a specific system from the Ground Mission Control Center (GMCC) are diminished considerably. Therefore, this demands survivability and intelligent level enhancement LSS ACS.
Technical Paper

Hybrid Adaptive Flight Control with Self-Improving Plant Model for Stability and Control of Damaged Aircraft

This paper presents a hybrid adaptive control method for maintaining stability and control of damaged aircraft. The hybrid method utilizes an adaptive parameter estimation scheme to improve a plant model in a flight control system. Two adaptive parameter estimation schemes are developed: 1) an indirect adaptive control law with normalization based on the Lyapunov direct method that uses tracking error for adaptation, and 2) a recursive least-squares law based on the optimal estimation method that uses plant model error for adaptation. Simulations show that the hybrid adaptive control can provide a significant improvement in the tracking performance of a flight control system.
Technical Paper

Filter Line Wiring Designs in Aircraft

Today's performance needs for commercial and military avionics systems require increasingly sophisticated electronic equipment and greater use of composite structures. As operational requirements become more critical, the level of electromagnetic interference (EMI) protection for electrical equipment is increasing. Harnessing and termination techniques must change to keep pace with state-of- the-art technologies. By effectively attenuating these undesirable energies on susceptible flight control and monitor wiring, the threat of disturbing electronic systems can be diminished. Some solutions to minimize the effects of EMI on systems through the use of proper terminations and radio frequency absorptive wire are discussed here.
Technical Paper

Who Needs Avionics Performance Minimums - The Government or You?

A lengthy effort to develop the minimum operational requirements of avionics systems needed for participation in the air traffic control system has not yet yielded standards or a means of administration acceptable to all segments of aviation. A new, more palatable approach by which users of the airspace can provide certain minimum operational characteristics in their airborne electronic systems shows promise. In order to make it work, FAA must clearly describe its electronic systems, how they work, and what their limitations are, so that willing participants may find out what they need to do in order to be right. Based on these system standards, minimum operational characteristics of airborne avionics can be developed and implemented. These may then meet with the approval of most of those affected, since the requirements will merely represent their own self-interest.
Technical Paper

Utilization Life of Electronic Systems - Aging Avionics Usable Life and Wear-Out Issues

How a system ages is central to the assessment of the effective utilization life of the system. Utilization life represents more than estimating the remaining life in an aged system, it is determining how to optimally plan a system's future management and future use to minimize the life cycle cost incurred. The consideration of utilization life of a system includes the physics of aging, damage accumulation techniques, mitigation of aging, qualified use of aged parts for spare replenishment, prognostics, and quantification of cost avoidance. Any approach to evaluating utilization life depends on a making an effective evaluation of the reliability, durability and safety of the system. Traditional Mean Time Between Failure (MTBF) metrics that assume a constant failure rate are likely to be less useful in the evaluation and practical implementation of utilization life concepts than Failure Free Operating Period (FFOP).

Lessons Learned from Developing, Implementing, and Operating a Health Management System for Propulsion and Drive Train Systems

SAE Aerospace Information Report AIR1871 provides valuable insight into lessons learned in the development, implementation, and operation of various health monitoring systems for propulsion engines and drive train systems. This document provides an overview of the lessons learned for ground-based systems, oil debris monitoring systems, lubrication systems, and Health and Usage Monitoring Systems (HUMS) for military and commercial programs. For each case study, this document presents a brief technical description, the design requirements, accomplishments, lessons learned, and future recommendations. The lessons learned presented in this document represent a fragment of the knowledge gained through experience when developing and implementing a propulsion health management system. Previous versions of this document contain additional lessons learned during the 1980’s and 1990’s that may be of additional value to the reader.
Technical Paper

Information Security Risk Management of Vehicles

The results of this work is allowed to identify a number of cybersecurity threats of the automated security-critical automotive systems, which reduces the efficiency of operation, road safety and system safety. Wired or wireless access of the information networks of the modern vehicles allows to gain control over power unit, chassis, security system components and comfort systems. According to the evaluating criterion of board electronics, the presence of poorly-protected communication channels, the 75% of the researched modern vehicles do not meet the minimum requirements of cybersecurity due to the danger of external blocking of vital systems. The revealed vulnerabilities of the security-critical automotive systems lead to the necessity of developing methods for mechanical and electronic protection of the modern vehicle. The law of normal distribution of the mid-points of the expert evaluation of the cyber-security of a modern vehicle has been determined.
Technical Paper

Design and Manufacturing of a Technology Demonstration Model for a Heat Rejection System Dedicated to Advanced Spacecraft and Payload Thermal Control

A Technology Demonstration Model (TDM) of a heat rejection system dedicated to advanced spacecraft and payload thermal control has been manufactured by AERITALIA under an European Space Agency (ESA) Contract. After survey and studies, AERITALIA has defined the characteristics and performances of a heat rejection system able to fulfil the requirements of some future spacecraft. The TDM is a model representative of this system in term of applicable software and hardware and has the main objective of demonstrating the performance and of validating the utilized hardware. The TDM consists of radiator panels (1.85×1.2 m),Spacelab type plumbing, fluid loop servicer with pump package, thermal control valves (by-pass and flow metering) and of an electronic control unit based on a microprocessor. The radiator panels, flow control valves and the control unit have been designed and developed for this application which serves as a prequalification programme.
Technical Paper

Design of an Actuator Fault Tolerant Flight Control System Using Fault Detection and Diagnosis

This paper presents a fault tolerant flight control design for the longitudinal linear model of the Boeing 737-100. The EMMAE (Extended Multiple Model Adaptive estimation) method is used to design the FDD process (Fault Detection and Diagnosis). Based essentially on a set of EKFs (Extended Kalman Filters), this method makes it possible to simulate several types of faults including stuck and oscillation. To develop the RFC (Reconfigurable Flight Control) law, SMC (Sliding Mode Control) method [11] is used. To rigorously investigate the performance of the overall system with respect of interactions between the two subsystems, The MRAC (Model Reference Adaptive Control) method [3] is used for comparison. Several simulation results using Matlab and Simulink show the desired system performance with fault compensation.
Technical Paper


A NUMBER of the cost aspects of management are discussed with a view toward improving overall airline efficiency. Utilization of airplanes alone does not greatly affect operating costs. Low costs are the result of high utilization of all equipment and personnel, the author stresses. Lengthening periods between inspection and overhaul-but always satisfying reliability requirements-can bring significant economies, a survey covering timing of various maintenance operations for one fleet shows. Five possible goals of cruise control are discussed, with emphasis on maximum payload miles per dollar. Analysis of the value of weight saving in aircraft results in a formula for finding the annual revenue value of the weight involved.

Handbook of Renewable Energy Technology

Effects of environmental, economic, social, political and technical factors have supported the rapid deployment of various sources of renewable energy-based power generation. The incorporation of these generation technologies have led to the development of a broad array of new methods and tools to integrate this new form of generation into the power system network. This book, arranged into six sections, highlights various renewable energy based generation technologies, and consists of a series of papers written by experts in their respective fields of specialization. The Handbook of Renewable Energy Technology will be of great practical benefit to professionals, scientists and researchers in the relevant industries, and will be of interest to those of the general public wanting to know more about renewable energy technologies.