Your Selections

Packer Engineering, Inc.
Show Only


File Formats

Content Types









Oxygen Separation from Lunar Regolith

Packer Engineering, Inc.-Peter J. Schubert
Published 2007-07-09 by SAE International in United States
A novel method for separating oxygen from lunar regolith has recently been granted two US patents. Early research at the system level has demonstrated the viability of this concept for silicon extraction. The focus of this paper is the process thermodynamics and energy scale-up for oxygen extraction. Starting with first principles, the separation of various oxygen-bearing minerals are analyzed with regards to vaporization, ionization, acceleration, separation by transverse electric fields, and condensation for collection of liquid oxygen. The next phase of work studies the geometric considerations of separation to obtain estimates of oxygen purity and throughput. This initial work will assess technical feasibility of oxygen extraction from lunar regolith, and provide a foundation for subsequent studies which must include various second-order effects such as self-shielding and beam diffusion needed to make estimates of throughput and overall efficiency.
Annotation icon

Model-based Development for Event-driven Applications using MATLAB: Audio Playback Case Study

Packer Engineering, Inc.-Peter J. Schubert
Delphi Electronics & Safety-Lev Vitkin
Published 2007-04-16 by SAE International in United States
Audio playbacks are mechanisms which read data from a storage medium and produce commands and signals which an audio system turns into music. Playbacks are constantly changed to meet market demands, requiring that the control software be updated quickly and efficiently. This paper reviews a 12 month project using the MATLAB/Simulink/Stateflow environment for model-based development, system simulation, autocode generation, and hardware-in-the-loop (HIL) verification for playbacks which read music CDs or MP3 disks. Our team began with a “clean slate” approach to playback architecture, and demonstrated working units running production-ready code. This modular, layered architecture enables rapid development and verification of new playback mechanisms, thereby reducing the time needed to evaluate playback mechanisms and integrate into a complete infotainment system. A system simulation environment which included a real-time operating system supports generic mechanism and behavior models, to account for functional differences in playback mechanism from different suppliers. The execution of HIL system simulation required the design and implementation of a communication protocol device which transceives command messages passed between the system environment and the playback mechanism.…
Annotation icon

Real-World Rollovers Reconstructed from Interviews and Measurements

Packer Engineering, Inc.-Peter J. Schubert
Published 2006-04-03 by SAE International in United States
Three vehicle rollovers have been reconstructed based on driver interviews and approximate measurements of crash artifacts. The purpose of this work is to provide insight into sensor signals prior to the onset of rollover. The three events include: a car-to-car T-bone leading to a roll of 90 degrees; an impact-induced skid leading to a roll with 6 quarter turns; and a single vehicle partly on-road event with three complete rolls. Sensor signals are derived using the PC-Crash tool, and characteristic features are identified. Insights derived from these events can aid in development of robust rollover detection algorithms and calibrations. Furthermore, by studying how pre-roll maneuvers may presage a rollover event, key requirements for system-of-systems safety architectures can be derived.
Annotation icon

Math-Based Design of Sensing Bladders

Packer Engineering, Inc.-Peter J. Schubert
Delphi Electronics & Safety-Roopesh Saxena, Sachi Pinagapani, Madana Gopal
Published 2006-04-03 by SAE International in United States
Through the use of finite-element modeling, pressure patterns on the underside of seat foam can be computed for a variety of occupants and seating positions. A design tool has been created which allows an engineer to evaluate different layouts for a pressure-sensing bladder in just minutes. This is important to meet FMVSS-208 safety regulations for vehicles sold in the US. Further, an artificial intelligence search engine has been applied to this problem to achieve near-optimal performance given the constraints of the seat design. Results are shown and compared with the traditional manual method of layout design.
Annotation icon

Executable Specs: What Makes One, and How are They Used?

Packer Engineering, Inc.-Peter J. Schubert
Delphi Electronics & Safety-Lev Vitkin, Frank Winters
Published 2006-04-03 by SAE International in United States
Model-based systems development relies upon the concept of an executable specification. A survey of published literature shows a wide range of definitions for executable specifications [1, 2, 3, 4, 5, 6, 7, 8, 9 and 10]. In this paper, we attempt to codify the essential starting elements for a complete executable specification-based design flow. A complete executable specification that includes a functional model as well as test cases, in addition to a traditional prose document, is needed to transfer requirements from a customer to a supplier, or from a systems engineer to electrical hardware and software engineers. In the complete form demonstrated here, sub-components of a functionally-decomposed system manifest as modular reuse blocks suitable for publication in functional libraries. The overarching definition provided by product architecture and by software architecture must also be harmoniously integrated with design and implementation. Using seven specific automotive examples, we illustrate effective ways in which executable specifications have been used in production-ready applications. Benefits of model-based development are captured, including earlier and more thorough testing, automatic document generation, and autocode…
Annotation icon

Computer-Aided 3-D Surface Reconstruction During High Speed Crush Events

Packer Engineering, Inc.-Albert V. Karvelis, Michael W. Rogers, Carl E. Anderson
Micro Systems Design-Aldis Liubinskas
Published 1991-02-01 by SAE International in United States
A system which can remotely measure detailed deformations of vehicle structures during crush events was developed. The system uses ordinary video or 16 mm high speed movie to capture the crush event. This information is digitized and analyzed using personal computers to perform photogrammetric manipulations which yield accurate surface geometries. The output is useful for comparison to computer simulations.This paper presents preliminary results regarding the accuracy of this system.
Annotation icon