Systems Engineering Commons^™

Implementation And Demonstration Of A Multiple Model Adaptive Estimation Failure Detection System For The F-16, Peter K. Eide

Theses and Dissertations

A Multiple Model Adaptive Estimation (MMAE) algorithm is implemented with the fully nonlinear six-degree-of-motion, Simulation Rapid-Prototyping Facility (SRF) VISTA F-16 software simulation tool. The algorithm is demonstrated to be capable of identifying flight critical aircraft actuator and sensor failures at a low dynamic pressure (20,000 ft, .4 Mach). Research included single and dual complete failures. Tuning methods for accommodating model mismatch, including addition of discrete dynamics pseudonoise and continuous measurement pseudonoise, are discussed and demonstrated. Scalar residuals within each filter are also examined and characterized for possible use as an additional failure declaration voter. Robustness to sensor failures provided by …

Development Of A Knowledge-Based System For Wastewater Pipeline Rehabilitation, David Allen Reaves

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this thesis is to study and develop a knowledge-based system to make decisions for the rehabilitation of wastewater pipelines. Development includes justification for the use of an expert system, data acquisition from knowledge experts, program model development, model testing, implementation and future considerations including expansion. The model is developed and implemented using an expert system shell called XIPlus ®.

This knowledge-based system is designed specifically for the Navy Public Works Center Utilities Department at Norfolk Naval Base in Norfolk, Virginia for making decisions for the rehabilitation of the 50-year-old wastewater collection system. Recent sewer collapses and a …

A Functional Architecture For Automated Highway Traffic Planning, H.-S. Jacob Tsao

Faculty Publications

In a fully automated Automated Highway System (AHS), the roadside control system and the vehicles themselves are responsible for moving the large number of vehicles safely and efficiently. Therefore, the task of operating an AHS is drastically different from and much more complex than its conventional counterpart. Resulting from a large number of design options, there exist many possible ways to operate an AHS. Each of these possible operating scenarios will support a different set of functions. A crucial task in AHS R&D is to evaluate and compare these potentially large number of different AHS operating scenarios with respect to …

Capacity Of Automated Highway Systems: Effect Of Platooning And Barriers, H.-S. Jacob Tsao, Randolph Hall, Bruce Hongola

Faculty Publications

The concept of Automated Highway Systems (AHS) is based on the belief that an appropriate integration of control and communication technologies placed on the vehicle and on the highway can lead to a large improvement in capacity and safety without requiring a significant amount of additional highway right-of-way. Stemming from this belief are various conceptual scenarios for vehicle/highway automation.An AHS consists of two major components: vehicle/highway automation technology and highway operating strategy. In this paper, we study the capacity of key AHS operating scenarios.

A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall

Faculty Publications

This paper develops a probabilistic model for analyzing longitudinal collision/safety between an abruptly decelerating vehicle and its immediate follower. The input parameters are the length of the gap between the two vehicles, their common speed prior to the failure, the reaction delay of the following vehicle and a bivariate distribution for the two deceleration rates. The output includes the probability of a collision and the probability distribution of the relative speed at collision time We use this model to compare the safety consequences associated with the platooning and “free-agent” longitudinal-separation rules. We also demonstrate that the free-agent rule implemented with …

Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao

Faculty Publications

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual …

A Study Of Similarity And Analogical Decision-Making In Collaborative Design, Christopher Edward Weeks

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this study is to investigate the role of similarity and analogy in design communication and propose a descriptive representation of the analogical decision-making process in the context of engineering design. It is proposed that social, cultural, and contextual knowledge are brought to bear on statements of need in the form of analogy as a means to elicit and evince potential design solutions. A goal of this study is to identify communicative behaviors, representing process variables of analogical decision-making, that can be used to describe how design information is represented, manipulated, and conveyed in a collaborative design effort. …

Constraints On Initial Ahs Deployment And The Concept Definition Of A Shuttle Service For Ahs Debut, Jacob Tsao

H.-S. Jacob Tsao

Highway automation and its evolution involve a multitude of systems issues. Particularly important and difficult in defining a deployment sequence is the very first step, i.e. the first user service involving fully automated freeway driving. However, this importance and the difficulty imply that many factors may severely constrain the initial deployment. After discussing the paramount importance of initial AHS deployment, this paper points out major high-level issues and constraints. Any realistic deployment strategy must take into consideration gradual technology maturation, introduction of new driver role and diminishing conventional driver role for automated driving, high cost of early-generation automation-equipped vehicles, gradual …

A Probabilistic Model For Avcs Longitudinal Collision/Safety Analysis, Jacob Tsao, Randolph Hall

H.-S. Jacob Tsao

This paper develops a probabilistic model for analyzing longitudinal collision/safety between an abruptly decelerating vehicle and its immediate follower. The input parameters are the length of the gap between the two vehicles, their common speed prior to the failure, the reaction delay of the following vehicle and a bivariate distribution for the two deceleration rates. The output includes the probability of a collision and the probability distribution of the relative speed at collision time We use this model to compare the safety consequences associated with the platooning and “free-agent” longitudinal-separation rules. We also demonstrate that the free-agent rule implemented with …