Notes From Class
Notes From Class
Week 1: August 31, 2010.
Week 2: September 7, 2010
Week 3: September 14, 2010
Note. This case study outlines a series of missteps in the design and implementation of the automated baggage handling system at Denver Airport over a sixteen year timeframe, 1989-2005.
Due date: September 28.
Week 4: September 21, 2010
Note. There are a lot of slides in this presentation that are not in the lecture notes, so you might like to make a hardcopy at some point.
Week 5: September 28, 2010
Note. Today will be our first of several lectures on model checking with LTSA. You can find a lot of support material on the CD distributed in class.
Weeks 8-9: October 19 and 26, 2010
Consider the railroad crossing problem shown in Figure 1.
Figure 1. Simplified model for the railroad crossing problem.
Part 1. Due November 1
Develop a detailed model of the railroad crossing problem in LTSA.
Your model should include processes for the sensors (e.g., a:sensor, b:sensor, c:sensor), the gate, the gate controller, and the train. Also indicate the property automata that you would use for safety and progress checks.
My suggestion is to keep the functionality of the sensors as simple as possible (i.e., simply measure whether or not the track is occupied by a train at a particular point) and then put all of the system smarts in the gate controller. The first and third sensors should detect the arrival and departure of a train. A safety violation will occur if the second sensor is activated before the gate has been completely lowered.
For some ideas on how to implement the gate controller, see the oneway bridge example in the ltsa distribution. The process is called BRIDGE, but it's really a traffic controller.
List all other assumptions that you make.
Part 2. Due November 8
Develop a detailed model of the railroad crossing problem in UPPAAL.
My suggestion is that you study and adapt the train-gate example discussed in class. Assign reasonable times for each activity and periods that a train will spend in each zone. Then try to identify boundaries that separate safe bebavior from unsafe behavior.
List all other assumptions that you make.
Note. Both LTSA and UPPAAL are implemented in Java.
If you have a Mac then Java will already be installed.
Look in /Program Files to see whether or not Java is installed on your PC. If not, then you can download Java (it's free!) from http://www.oracle.com/technetwork/java/index.html .
Week 10: November 1-2, 2010
Lecture Time: Monday, November 1, 5-6 pm.
Where: Rm 1146, A.V. Williams Buidling.
Abstract. The practice of systems engineering is transitioning from a document-based approach to a model-based approach. In a model-based approach, emphasis is placed on defining, managing, and controlling a coherent model of the system that can then be reflected in systems engineering documentation such as specifications, interface control documentation, system design documentation, trade studies, and analysis reports.
This presentation will provide an overview of the benefits of the model-based systems engineering (MBSE) approach over a document-based approach in terms of how it can improve productivity, quality, and enhance communications among the development team. The presentation also highlights how MBSE can be used to flow requirements down from the mission level to the system design and to hardware and software components, and how SysML integrates with other models. Some of the lessons learned from early applications of MBSE using the SysML standard will also be presented.
Biography. Sanford Friedenthal is a Lockheed Martin Fellow and currently leads an effort to enable Model Based Systems Development (MBSD) and other advanced practices across the company. His experience includes the application of systems engineering throughout the system life-cycle from conceptual design, through development and production on a broad range of systems in aerospace and defense. He has been a systems engineering department manager, and a lead developer of advanced systems engineering processes and methods including the Lockheed Martin Integrated Enterprise Process and the Object-Oriented Systems Engineering Method (OOSEM). Mr. Friedenthal was a leader of the Industry Standards effort through the Object Management Group (OMG) and INCOSE to develop the Systems Modeling Language (OMG SysML) that was adopted by the OMG in 2006. He is co-author of A Practical Guide to SysML
Week 12: November 16, 2010
Last Modified November 16, 2010,
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