6.302 iLab Homepage
A WebLab for Signals, Systems, Circuits, and Control
Frequency-domain techniques are among the most important concepts that
students learn in courses in signals, systems, circuits, and control.
Simple laboratory assignments illustrating these techniques provide
students with both crucial learning opportunities and practical
experimental experience. These experiments encourage both sustained
student interest and subject retention. Unfortunately, experimental
work by students requires laboratory space, stocked with test equipment
and staffed by teaching assistants. Many engineering classes do not
include a lab component because of the significant expense involved.
This remote laboratory project provides for much more efficient sharing
of expensive measurement equipment. Students can conduct the
experiments from any computer on their own schedule, instead of in a
specialized lab on the lab's schedule.
In this weblab framework, students use a Java-based Lab Client to
configure system parameters and submit jobs to the Lab Server. The Lab
Server computer and a dynamic signal analyzer (an HP 3562A, as shown at
right) take frequency-response measurements of the system-under-test.
This weblab system allows the measurements of electronic,
electromechanical, mechanical, and thermal systems.
The Java-based Lab Client runs in any web browser, and the Lab Server
and laboratory hardware can be located in any remote location.
Communication between the Client and the Server is mediated by the iLab
Service Broker (developed by the MIT CECI and iCampus). In a typical
student experiment, the student provides the system settings and
measurement parameters (1). The Lab Server sets up the system under
test (2) and drives the dynamic signal analyzer (3). The analyzer
measures the frequency response of the system (4), and returns the data
to the Lab Server (5). The Lab Server forwards the measured data to the
Client (6), which displays the information for the student.
- Gerardo Viedma, Isaac J. Dancy, and Kent H. Lundberg. "A Web-Based Linear-Systems iLab." American Control
Conference 2005, June 8-10, 2005, Portland, Ore.
- Viedma, Gerardo, "Design and Implementation of the Feedback Systems Web Laboratory",
Master of Engineering Thesis, MIT, February 2005.
- Lokanathan, Sriganesh, "Extensions to
the Feedback Systems Web Laboratory Client Prototype", Advanced
Undergraduate Project Report, MIT, July 2004.
- Viedma, Gerardo, "Design and
Implementation of a Feedback Systems Web Laboratory Prototype",
Advanced Undergraduate Project Report, MIT, May 2004.
- Williams, Brian, "Educational Java Applet for
Linear System Responses", Advanced Undergraduate Project Report,
MIT, May 2004.
- Johnson, Rayal, "Programmable
State-Variable Filter Design for a Feedback Systems Web-Based
Laboratory", Advanced Undergraduate Project Report, MIT, February
- Gerardo Viedma, The 6.302
weblab experiment engine, 6.302 Weblab Project, August 2, 2004.
- Kent Lundberg, Some API changes we'd
like to see, 6.302 Weblab Project, July 28, 2004.
- Rayal Johnson, Using state variable
filters to create lead/lag filters, 6.302 Weblab Project, April 29,
- XML Experiment Routine:
used by the course staff to specify the experimental routines to be run
by the lab hardware connected to the Lab Server. It is also used to
specify what inputs need to be provided by students when running their
experiments from the Lab Client.
- XML Lab Configuration: this
file is generated dynamically at the Lab Server based on the Experiment Routine. It is used to
populate the Lab Client's dynamic UI components. These components
include the input text fields and their corresponding labels, the lab
description, available offline results, and the schematic diagram for
the current experiment.
- XML Experiment
Specification: this file consists of the experimental parameters
specified by the user through the input text fields at the Lab
Client. The Lab Server uses these experimental parameters to set up the
experiment hardware appropriately when running the user's experiment
- XML Experiment Result: this
file consists of frequency, magnitude, and phase vectors of results for
the user's successfully completed experiment.
- XML Offline Data: experiment results from
previously run experiments that are made available online for public
consumption through the Lab Client.
- XML Saved Setup file from client
- Client exported files:
screen shot (jpg)
- Graphic files: block diagram
and complete schematic
Laboratory experience is an irreplaceable component of education. The
purpose of iLabs is not to replace laboratory work by students, but to
insert experimental work where none existed before.
Professor del Alamo's Microelectronics
Weblab for 6.012 is a perfect example of this philosophy. Before
the weblab was deployed, there was no laboratory work in the class.
Providing students with laboratory space, stocked with equipment, and
staffed by teaching assistants would have been impossible for a
traditional lab. However, with the iLab architecture, students can now
gather real transistor data without the prohibitive expense of space,
equipment, and staff.