Towards self-predicting systems: What if you could ask ‘what-if’?

2006 ◽  
Vol 21 (3) ◽  
pp. 261-267 ◽  
Author(s):  
ENO THERESKA ◽  
DUSHYANTH NARAYANAN ◽  
GREGORY R. GANGER
Keyword(s):  
System Design ◽  
Large System ◽  
System Management ◽  
System Behavior ◽  
Search Problems ◽  
Interactive Exploration ◽  
Design Changes ◽  
Rules Of Thumb ◽  
System Changes ◽  
Management Problems

Today, management and tuning questions are approached using if… then… rules of thumb. This reactive approach requires expertise regarding system behavior, making it difficult to deal with unforeseen uses of a system’s resources and leading to system unpredictability and large system management overheads. We propose a What…if… approach that allows interactive exploration of the effects of system changes, thus converting complex tuning problem into simpler search problems. Through two concrete management problems, automating system upgrades and deciding on service migrations, we identify system design changes that enable a system to answer What…if… questions about itself.

Plant-Limited Co-Design of an Energy-Efficient Counterbalanced Robotic Manipulator

2012 ◽  
Author(s):  
James T. Allison
Keyword(s):  
System Design ◽  
Physical System ◽  
Control Design ◽  
Robotic Manipulator ◽  
Plant Design ◽  
Design Modification ◽  
Baseline Design ◽  
Design Changes ◽  
Pick And Place ◽  
Place Task

Modifying the design of an existing system to meet the needs of a new task is a common activity in mechatronic system development. Often engineers seek to meet requirements for the new task via control design changes alone, but in many cases new requirements are impossible to meet using control design only; physical system design modifications must be considered. Plant-Limited Co-Design (PLCD) is a design methodology for meeting new requirements at minimum cost through limited physical system (plant) design changes in concert with control system redesign. The most influential plant changes are identified to narrow the set of candidate plant changes. PLCD provides quantitative evidence to support strategic plant design modification decisions, including tradeoff analyses of redesign cost and requirement violation. In this article the design of a counterbalanced robotic manipulator is used to illustrate successful PLCD application. A baseline system design is obtained that exploits synergy between manipulator passive dynamics and control to minimize energy consumption for a specific pick-and-place task. The baseline design cannot meet requirements for a second pick-and-place task through control design changes alone. A limited set of plant design changes is identified using sensitivity analysis, and the PLCD result meets the new requirements at a cost significantly less than complete system redesign.

Telematics Issues in California's VII Testbed (Telematikaspekte im kalifornischen VII Feldtest)

2008 ◽  
Vol 50 (4) ◽  
Author(s):  
Susan Dickey ◽  
Joel VanderWerf
Keyword(s):  
Research And Development ◽  
System Design ◽  
Field Test ◽  
Information Sources ◽  
Protocol Design ◽  
Wireless Access ◽  
External Information ◽  
System Management ◽  
Management Experience ◽  
Vehicle Infrastructure Integration

SummaryThe VII California project has developed a testbed of infrastructure-connected wireless access points on urban arterials and expressways. This paper discusses the use of the testbed for research and development of technologies and applications related to vehicle-infrastructure integration. The focus of this paper is on protocol design, connectivity to traffic signal state, external information sources, and system management. Experience gathered from the testbed will contribute to future field-test deployments, application design, scalability predictions, and input to broader system design and standardization efforts.

Modeling Air Traffic Controller Performance in Highly Automated Environments

1989 ◽  
Vol 33 (2) ◽  
pp. 47-51 ◽  
Author(s):  
Elizabeth D. Murphy ◽  
Ray A. Reaux ◽  
Lisa J. Stewart ◽  
William D. Coleman ◽  
Kelly Harwood
Keyword(s):  
System Design ◽  
Traffic Control ◽  
Human Performance ◽  
The United States ◽  
Air Traffic ◽  
Automated System ◽  
Performance Variables ◽  
Design Changes ◽  
Controller Performance ◽  
Performance Dimensions

As increasing levels of automation are planned for the United States' air traffic control system, there is a need to assess planned system design changes for their potential effects on human performance. The model of controller performance developed by this work permits the comparison of prior and planned system transition states on several performance dimensions: perceptual, analytic, response, and resource management. Systematic predictions of performance provide a basis for identifying potential trouble spots in a planned system. The model can be employed to determine whether system design changes will improve controller performance without placing unreasonable demands on the controller's resources. It can be tailored to represent human performance variables and sources of resource demand in any complex automated system.

Exploratory design using constraints

1987 ◽  
Vol 1 (1) ◽  
pp. 59-71 ◽  
Author(s):  
Weng Tat Chan ◽  
Boyd C. Paulson
Keyword(s):  
Structural Design ◽  
Computer Aided Design ◽  
Design Solution ◽  
Simple Scheme ◽  
Dual Nature ◽  
Design Changes ◽  
Heuristic Procedures ◽  
Rules Of Thumb ◽  
Design Consistency ◽  
Aided Design

Engineering design involves the evaluation and satisfaction of a wide variety of constraints. The ability to represent and process these constraints in a computer is important for the verification of the output produced by computer-aided design programs. Constraints need not only check designs but can also be used to derive design solution s that satisfy constraints. The paper discusses how to represent the dual nature of constraints so that design consistency is maintained as the design evolves.Assumptions and rules of thumb are used frequently in design to propose initial solutions. We represent the logic behind the derivation of these assumptions as heuristic procedures and maintain the dependencies between these assumptions and their consequents as an aid to the management of design consistency. We also propose a simple scheme, involving the partitioning of the design modules, to effect design changes when constraint violations occur. An example from structural design illustrates the methodology.

Plant-Limited Co-Design of an Energy-Efficient Counterbalanced Robotic Manipulator

2013 ◽  
Vol 135 (10) ◽  
Author(s):  
James T. Allison
Keyword(s):  
System Design ◽  
Physical System ◽  
Control Design ◽  
Robotic Manipulator ◽  
Plant Design ◽  
Design Modification ◽  
Baseline Design ◽  
Design Changes ◽  
Pick And Place ◽  
Place Task

Modifying the design of an existing system to meet the needs of a new task is a common activity in mechatronic system development. Often, engineers seek to meet requirements for the new task via control design changes alone, but in many cases new requirements are impossible to meet using control design only; physical system design modifications must be considered. Plant-limited co-design (PLCD) is a design methodology for meeting new requirements at minimum cost through limited physical system (plant) design changes in concert with control system redesign. The most influential plant changes are identified to narrow the set of candidate plant changes. PLCD provides quantitative evidence to support strategic plant design modification decisions, including tradeoff analyses of redesign cost and requirement violation. In this article the design of a counterbalanced robotic manipulator is used to illustrate successful PLCD application. A baseline system design is obtained that exploits synergy between manipulator passive dynamics and control to minimize energy consumption for a specific pick-and-place task. The baseline design cannot meet requirements for a second pick-and-place task through control design changes alone. A limited set of plant design changes is identified using sensitivity analysis, and the PLCD result meets the new requirements at a cost significantly less than complete system redesign.

On the Coupling of Designer Experience and Modularity in the Aerothermal Design of Turbomachinery

2008 ◽  
Author(s):  
Jerome P. Jarrett ◽  
Tiziano Ghisu ◽  
Geoffrey T. Parks
Keyword(s):  
Exchange Rates ◽  
System Design ◽  
Design Process ◽  
System Performance ◽  
Preliminary Design ◽  
Aerodynamic Design ◽  
Potential Cost ◽  
Final Performance ◽  
Design Variables ◽  
Rules Of Thumb

The turbomachinery aerodynamic design process is characterized both by its complexity and the reliance on designer experience for success. Complexity has led to the design being decomposed into modules; the specification of their interfaces is a key outcome of preliminary design and locks-in much of the final performance of the machine. Yet preliminary design is often heavily influenced by previous experience. While modularity makes the design tractable, it complicates the appropriate specification of the module interfaces to maximize whole-system performance: coupling of modularity and designer experience may reduce performance. This paper sets out to examine how such a deficit might occur and to quantify its cost in terms of efficiency. Two disincentives for challenging decomposition decisions are discussed. The first is where tried-and-tested engineering “rules of thumb” accord between modules: the rational engineer will find alluring a situation where each module can be specified in a way that maximizes its efficiency in isolation. The second is where there is discontinuity in modeling fidelity, and hence difficulty in accurately assessing performance exchange rates, between modules. In order to both quantify and reduce the potential cost of this coupling we have recast the design problem in such a way that what were previously module interface constraints become key system design variables. An example application of our method to the design of a generic turbofan core compression system is introduced. It is shown that nearly 1 percentage point equivalent compressor adiabatic efficiency can be saved.

Payment Theory and the Last Mile Problem

2020 ◽  
Vol 48 (3) ◽  
pp. 474-479 ◽  
Author(s):  
John V. Jacobi
Keyword(s):  
Primary Care ◽  
System Design ◽  
Financial Support ◽  
Health Reform ◽  
Large System ◽  
Physician Payment ◽  
Patient Centered ◽  
Last Mile ◽  
Last Mile Problem ◽  
Reform Debate

Health reform debate understandably focuses on large system design. We should not omit attention to the “last mile” problem of physician payment theory. Achieving fundamental goals of integrative, patient-centered primary care depends on thoughtful financial support. This commentary describes the nature and importance of innovative primary care payment programs.

A novel precision bender system for focusing mirrors

2010 ◽  
Vol 1 (MEDSI-6) ◽  
Author(s):  
E. Trakhtenberg ◽  
J. Collins ◽  
O. Schmidt
Keyword(s):  
Synchrotron Radiation ◽  
System Design ◽  
Atmospheric Pressure ◽  
Small Diameter ◽  
Stepper Motor ◽  
Prototype System ◽  
Test Results ◽  
Design Changes ◽  
Photon Source ◽  
Better Than

A novel mirror bender system utilizing cam-shaft mover (CSM) with 100 µm eccentricity was designed and successfully tested. The system was initially tested and characterized in the laboratory, and then later the performance was verified using the Advanced Photon Source synchrotron radiation source. The force from the two separate CSMs is translated to both ends of a mirror through a small-diameter bellows feed-through. The system uses an internal spring assembly to compensate for atmospheric pressure. A compact gear box with 10:1 ratio between the stepper motor and cam shaft is used to increase the precision of the bender system. This bender system is equipped with a precise rotary potentiometer and load cell for feedback. A system resolution better than 0.2 µm per step was achieved. This bender system was designed as a separate unit, is very compact and can be used to bend a mirror in both the vertical and horizontal planes. Details of the system design, changes made from the prototype system to the production unit and test results are presented here.

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