1

A tutorial on the VISIR Open Lab Platform and an invitation to join the VISIR Community

How to open a local electronics laboratory for remote access

04/20/231 REV 2009

2

Outline of the presentation of the VISIR Open Laboratory Platform

Introduction and background to VISIR Demonstration of an existing VISIR Lab The aim of the VISIR project Overview of the Open Lab platform How to join the VISIR project Conclusions and further development

04/20/23 REV 20092

3

Local Electronics Laboratory for Undergraduate Education at BTH

04/20/23 REV 20093

• 16 students share 8 identical workbenches• Open during 4 hour supervised classes only• Students need much more time in the laboratory

Instructor’s desk

4

Background

In 1999 a remote laboratory project was started to supplement local instructional laboratories and to provide free access to expensive experimental equipment

Today laboratories in electronics, security, radio and signal processing are online and used in regular courses for students who can be on campus or off campus

At the end of 2006 a disseminating project, VISIR, was started

04/20/234 REV 2009

5

Why Starting with Laboratories for Electrical Experiments?

Instructional laboratories for electrical experiments contain the same equipment at most universities – a de facto standard

They are easy to open for online access preserving the context

04/20/235 REV 2009

6

The VISIR Open Electronics Laboratory

Internet

Web ServerClient PC

Client PCResistance

Op amp

Demonstrations

04/20/236 REV 2009

7

VISIR Benefits to Students

Free access to the experimental equipment used in the laboratory classes from anywhere

Safe experimenting within limits set by the teacher

Excellent for practising laboratory work 24/7

04/20/237 REV 2009

8

VISIR Benefits to Universities

Supervised laboratory classes for off-campus students using appropriate teleconferencing tools can be offered

The students can do much laboratory work on their own

Low-cost individaul assessment of laboratory work possible

04/20/238 REV 2009

9

The Aim of the VISIR Project

Is establishing a VISIR Community of collaborating universities/organizations further developing the platform and sharing equipment and course material

Is distributed laboratories where the workbenches are set up by members of the Community

04/20/239 REV 2009

10

The VISIR Open Laboratory Platform Software Distribution

A public subversion repository with all software modules are available (http://svn.openlabs.bth.se/trac/)

Members of the VISIR Community will be granted write access to branches in the repository

Write to the trunk is limited and will require code review

04/20/23 REV 2009

11

Laboratory Course Administration

Different roles such as administrator, teacher and student are defined and they have different access rights

Time reservation for laboratory classes as well as for the students’ own experiments are provided

The web interface is used to introduce courses, lab sessions, personal accounts etc.

04/20/2311 REV 2009

12

Online Workbench

04/20/2312 REV 2009

13

Distributed Instruments

XML, TCP/IP

Client computerside

EquipmentServer side

IVI compliantdriver

It is possible to use a virtual front panel depicting one instrument model to control a different instrument model as long as the performance of the real instrument is equal or better than the performance of the depicted instrument.

04/20/2313 REV 2009

14

VISIR Standards

04/20/2314 REV 2009

Agilentpanels

Tektronixpanels

NI Softpanels

IVI compliantfunctions

GPIB

PXI

LXI

Universityselector

Studentselector

XML based protocols

15

Instrument functionality defined by IVI Foundation

8 instrument classes are now defined– DC power supply, DMM, function generator, oscilloscope,

power meter, RF signal generator, spectrum analyzer, and switch

Base Class Capabilities– common across most of the instruments available in the

class Class Extension Capabilities

– groups of functions, attributes, and attribute values that represent more specialized features of an instrument class

04/20/2315 REV 2009

16

Instrument drivers

VISIR recommends IVI drivers The VISA standard is accepted too but the

instrument functions should be those defined by the IVI standard

04/20/2316 REV 2009

17

Virtual Instrument Shelf

A virtual instrument shelf is needed because other universities use other models in their local laboratories or want, for example, LabVIEW style front panels

It should be possible for students to select the instrument models they are used to or want to become familiar with

04/20/2317 REV 2009

18

Example of Virtual Instrument shelf

04/20/2318 REV 2009

19

The VISIR Switching Matrix Supports

Novices practicing wiring and experimenting on simple circuits described in instruction manuals

Advanced students testing ready-made complex circuits and using the matrix to move the test probes

04/20/2319 REV 2009

20

The Switching Matrix

04/20/2320 REV 2009

21

Switching Matrix Performance

The function generatorNI PXI-5402 generates1 MHz square wave.

The oscilloscopeNI PXI-5112 displaysThe data

Bandwidth test on a matrix with 8 boards04/20/2321 REV 2009

22

How to Join the VISIR Community and Set up a Workbench

Download the software and instructions published at http://svn.openlabs.bth.se/trac

Buy the PXI hardware from National Instruments

The switching matrix is commercially available

04/20/2322 REV 2009

23

Competences Required to Implement a VISIR Online Workbench

Experience of analog electronics, PXI, and LabVIEW

IT experience (Web, PHP, MySQL, XML, C++, FLASH etc.)

04/20/2323 REV 2009

24

Further development of the VISIR platform

Additional virtual front panels depicting instrument models used in the VISIR community

Interface to a learning management system such as Moodle

Adding new tools for communication between people in the laboratory

A VISIR grid laboratory based on web services

04/20/2324 REV 2009