EDUCATIONAL LABORATORY VIRTUAL
INSTRUMENTATION SUITE (ELVIS)
LABORATORY DEVELOPMENT
PROJECT DESIGN
TEAM # MAY03-19
CLIENT:
National Instruments
FACULTY ADVISORS:
Prof. Mani Mina
Prof. Diane Rover
GROUP MEMBERS:
Michael Ballou
Ryan Hankins
Jason Salz
David Schmidt
Dayu Zhou
DECEMBER 18, 2002
Table Of Contents
List Of Figures ................................................................................................................................ ii
List Of Tables ................................................................................................................................ iii
Abstract ........................................................................................................................................... 1
Acknowledgement .......................................................................................................................... 1
Definition of Terms......................................................................................................................... 1
1 Introduction ................................................................................................................................. 2
1.1 General Background .................................................................................................... 2
1.2 Technical Problems ...................................................................................................... 3
1.3 Operating Environment ................................................................................................ 3
1.4 Intended User ............................................................................................................... 3
1.5 Assumptions and Limitations ...................................................................................... 3
2 Design Requirements .................................................................................................................. 4
2.1 Design Objectives ........................................................................................................ 4
2.2 Functional Requirements ............................................................................................. 5
2.3 Design Constraints ....................................................................................................... 5
2.4 Measurable Milestones ................................................................................................ 6
3 End-Product Description ............................................................................................................. 7
4 Approach and Design .................................................................................................................. 8
4.1 Technical Approaches .................................................................................................. 8
4.2 Technical Design ......................................................................................................... 8
4.3 Testing Description .................................................................................................... 10
4.4 Risks and Risk Management ...................................................................................... 10
4.5 Recommendation for Continued Work ...................................................................... 10
5 Financial Budget ....................................................................................................................... 11
6 Personnel Effort Budget ............................................................................................................ 11
7 Project Schedule........................................................................................................................ 12
8 Project Team Information ......................................................................................................... 13
9 Summary ................................................................................................................................... 14
10 References ............................................................................................................................... 14
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List Of Figures
Figure 1.1 – ELVIS ......................................................................................................................... 2
Figure 3.1 – Current Lab System .................................................................................................... 7
Figure 3.2 – ELVIS Lab System ..................................................................................................... 7
Figure 7.1 – Project Schedule ....................................................................................................... 12
ii
List Of Tables
Table 5.1 – Financial Budget ........................................................................................................ 11
Table 6.1 – Personnel Effort Budget............................................................................................. 11
iii
Abstract
The labs of several electrical engineering courses at Iowa State University are being
considered for an upgrade to a new data acquisition (DAQ) system. The team must become
familiar enough with this system to document the conversion process of the electrical
engineering labs to the new system. ELVIS in conjunction with LabVIEW will be used to
collect and measure data and input the data into a computer for processing. The team will
determine the instrumentation needs of a particular lab and replace the instruments
functionality with an equivalent ELVIS and LabVIEW setup. The end result will be a
complete set of documentation for converting future labs, as well as a demonstration of a
converted lab. This project is keeping Iowa State labs on the cutting edge of technology to
better prepare engineers for the future.
Acknowledgement
The team would like to acknowledge David Gardner and Randy Hoskin of National
Instruments for providing two ELVIS systems and DAQ boards that will be used through the
project.
Definition of Terms
o Educational Laboratory Virtual Instrumentation Suite (ELVIS) – A hardware DAQ
system.
o Data acquisition (DAQ) – Process of collecting and measuring electrical signals from
sensors, transducers, and test probes or fixtures, and inputting them to a computer for
processing.
o LabVIEW - A graphical programming language used for creating test, measurement, and
automation applications that has been developed by National Instruments.
o Traditional laboratory instruments – Unique instruments providing different
functionalities. Examples include function generators, digital multimeters and
oscilloscopes.
o Virtual Instruments – Software representations of traditional instruments. Virtual
instruments are used to control and take readings from a hardware device capable of
communicating via a DAQ card.
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1 Introduction
At Iowa State University, computer and electrical engineering students are given the
opportunity to learn electrical engineering concepts through hands on work in course labs. A
variety of equipment and instrumentation, such as voltage and current sources, function
generators and oscilloscopes, are provided for students to test the behavior of actual electrical
circuits and systems.
Though exposure and familiarity to a wide variety of instruments is valuable, students often
spend more time configuring instruments and manually recording data than is spent
implementing circuits and analyzing the data. The ELVIS system has been designed to
consolidate a variety of instruments into one functionally equivalent system and to provide a
means of automatic data acquisition.
1.1 General Background
The goal of this project is to convert at least one current lab to the ELVIS and LabVIEW
system and to provide documentation for converting future labs. The first step is spending
time working with ELVIS and LabVIEW so that the group is accustomed to the system
and can work proficiently with it. At least one lab will then be converted completely to
the ELVIS and LabVIEW system. The group will document the conversion process and
then document the steps that need to be taken to convert future labs.
Figure 1.1 – ELVIS
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1.2 Technical Problems
The major foreseeable problem that the group may encounter is a difficulty in
configuring virtual instruments to behave like real life instruments. Many instruments are
provided in LabVIEW and it is possible that after some trial and error a suitable virtual
equivalent could be found. If that scenario is not possible then an instrument will have to
be created by the group members.
Technical issues with the ELVIS hardware also exist. The hardware version available to
the senior design team is still in beta development. This hardware does not support either
current measurement or current output. Measurement inaccuracies as high as 20% from
expected values have also been observed.
1.3 Operating Environment
After completion of this project, the system would most likely be used by electrical and
computer engineering students while in lab. The EE 201 labs are the primary attention of
the project group. Freshman students who have minimal engineering knowledge
generally attend these labs, so converted labs would have to be simple so as not to
confuse the user. New engineering students may also unknowingly create circuits with
inputs or outputs that could damage the ELVIS hardware.
1.4 Intended User
The intended user for this project is the Department of Electrical and Computer
Engineering. This department can use the ELVIS and LabVIEW system developed by the
project team to upgrade the current labs used for certain courses.
The EE 201 lab is the primary lab to be integrated with the new ELVIS and LabVIEW
system. The new system would allow for easier reading of measurements taken in the lab
and can be used as a replacement for several traditional lab instruments.
1.5 Assumptions and Limitations
Assumptions made while planning the project are as follows:
1. National Instruments will provide the ELVIS and DAQ hardware.
2. Virtual instruments that are used by LabVIEW and are compatible with ELVIS
will be provided.
3. The group can create virtual instruments that are not provided.
4. It is assumed that the DAQ can capture all data required by the lab.
5. National Instruments will provide necessary information regarding complications
with the ELVIS hardware.
6. Hardware is installed and correctly configured.
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Possible limitations that may be encountered are as follows:
1. Functionality of virtual instruments controlled by LabVIEW may not exactly
match the functionality provided by the actual instruments currently used in lab.
2. The ELVIS hardware may not be able to generate the variety of signals currently
required by a lab.
3. Breadboards on which students implement circuits are somewhat expensive which
could preclude them from being removed from the lab.
4. Hardware is still in the beta stage of development and does not meet all design
requirements with regards to measurement accuracy.
2 Design Requirements
This section contains four components- design objectives, functional requirements, design
constraints, and measurable milestones. Each of these sections comprises requirements that
the ELVIS project must take into account during design and are further described below.
2.1 Design Objectives
Listed below are the technical challenges that must be met by the design of ELVIS. The
first two items are objectives that the team must meet before beginning actual work on
the project, whereas the last two are part of the end result.
o Gain an understanding of National Instruments’ LabVIEW:
By reading NI documentation, following LabVIEW tutorials and by hands-on
experimentation, the team will become familiar with LabVIEW.
o
Gain an understanding of National Instruments’ ELVIS DAQ System:
The team will use the ELVIS setup and associated documentation provided by NI
to learn how the system works.
o
Provide complete documentation to convert all EE 201 labs to the ELVIS system:
This is the core of the project and will consume a majority of the time. After
becoming comfortable with ELVIS/LabVIEW, the group will proceed to write out
the steps necessary to implement the entire EE 201 laboratory using the new
system. Given the limitations of the beta version of ELVIS available to the group,
some of the documentation for converting EE 201 labs may require altering the
labs themselves. In cases where current measurement is required, it may be
necessary to find a way to work around that measurement.
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o
Carry out the conversion of selected EE 201 labs to the ELVIS system:
As a demonstration of the project, the group will attempt to implement as many of
the EE 201 labs as possible using the hardware and software provided by NI. In
some cases this may not be possible due to limitations in the current version of
ELVIS. In such cases, the changes necessary to make ELVIS more appropriate for
this project will be documented.
2.2 Functional Requirements
The three requirements below specify the necessary functionality of the finished ELVIS
lab setup. These goals are crucial to the success of the project.
o Provide clear, concise, and accurate documentation for all EE 201 labs:
The documents produced must be written in such a way that undergraduate
engineering students will have no problems understanding and following the
instructions.
o
The new system will teach the same objectives as the previous lab system:
The revised labs will not be substantially changed in terms of content and
concepts taught. Students will follow the same procedures but instead of using
hardware and instruments, they will be able to use a computer to manipulate
virtual instruments.
o Provide students with a clear virtual instrument interface:
The team must produce a functional computerized interface using LabVIEW that
students will find intuitive and easy to use.
2.3 Design Constraints
The next four items are constraints that limit the project to ensure its practicality and
usefulness to the EE/CprE department.
o Lab procedures must not be fundamentally changed:
Conversion to the ELVIS system must not change the basic ideas of the lab.
o Students should be able to complete the labs in approximately the same amount of
time as with the previous system:
The new ELVIS system should not require students to spend more time
completing the labs. Ideally it will free up time spent fighting with poorly
calibrated instruments to be used more productively.
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o Labs must run on available computers using the donated ELVIS system:
All the labs must work using typical EE/CprE lab PC hardware running Windows
2000 in conjunction with the new ELVIS system.
o The system must be able to provide a virtual instrument to replace as many
instruments as possible:
The new ELVIS system must either utilize pre-supplied virtual instruments to
implement current hardware or new virtual instruments created by the team. Any
signal measurement or generation not provided by ELVIS will require a
traditional lab instrument.
2.4 Measurable Milestones
Below is a list of milestones by which the project’s progress and success may be gauged.
The following criteria will be used to provide a relative indication of success:
100%
The milestone was successfully met or exceeded.
75%
The milestone was mostly met with one or more parts left unfinished.
50%
A portion of the milestone was accomplished with significant sections left
undone.
25%
An effort was made and some progress made but mostly undone.
0%
No effort made.
o Analyze necessary virtual instruments: (5%)
The team must determine which of the necessary virtual instruments (such as
multimeters, ammeters, and oscilloscopes) are currently available and which must
be created. 100% success for this milestone will be considered providing the
necessary virtual instruments for the labs. Anything less will be evaluated using
the percentages listed above.
o Completion of LabVIEW virtual instrument interface: (40%)
Completing the computer interface will allow testing of the converted labs.
If the team is able to provide all the graphical interfaces for the converted labs,
this milestone will be 100% successful. Providing less than this will be judged
according to the above percentages.
o Completion of necessary documentation: (25%)
Finishing the documentation for each lab will be a major portion of the project. If
all labs are fully documented the milestone will be considered successfully
completed. Less than complete documentation will result in a lower percentage of
success.
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o Completion of testing: (10%)
Thorough testing of the documentation for readability and accuracy is necessary.
Testing of the implemented labs to ensure complete functionality is also
important. If all the necessary testing is completed, the milestone will be
completely met. Otherwise, completion success will be lowered according to the
percentages above.
o Revision: (10%)
Upon testing, any errors or other problems in the documentation or labs will be
resolved. This revision process will continue until the requirements for the project
are met. If errors found during testing or review are not corrected, less than 100%
success of this milestone will be the result.
o Working demonstration of selected labs using ELVIS system: (10%)
The last step of this project involves demonstrating selected EE 201 labs. If
everything was successfully completed up to this point, the demonstration should
proceed without problems. 100% success will be considered to be project
demonstration without problems.
3 End-Product Description
The basic electrical engineering laboratory EE 201 will be converted from traditional
multimeter-based experiments to labs using the new ELVIS DAQ system. ELVIS will gather
the data related to the test circuits and transfer the data to a computer with LabVIEW
installed. Students can then use graphical interfaces generated by LabVIEW to analyze the
data. With ELVIS, students are relieved of errors and problems of measuring equipment and
the efficiency of laboratory education will be enhanced.
Figure 3.1 – Current Lab System
Figure 3.2 – ELVIS Lab System
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4 Approach and Design
This section is composed of the following sections- technical approaches, technical design,
testing description, and risk and risk management. These sections describe important phases
of the approaches used in the design and testing process.
4.1 Technical Approaches
The primary objective of this project is to evaluate the usefulness of ELVIS in a college
environment and to provide documentation that outlines the necessary steps required to
use ELVIS in a lab environment. To successfully convert the existing EE 201 laboratory
to make use of the ELVIS system, three major steps must be followed; namely, learning
the functionalities and usages of ELVIS and LabVIEW, creating graphical interfaces
using LabVIEW and providing documentation for future lab conversions.
There are several resources that can be utilized to learn the functionality of ELVIS. The
primary source of information will be the documentation written by NI and supplied with
ELVIS. However, due to the fact that ELVIS is still in active development, the
documentation may not always accurately reflect the true state of the ELVIS hardware.
Technical support from National Instruments will be available to help resolve issues
stemming from possible documentation inaccuracies.
For select labs in the existing EE 201 lab manual, the team will create the required
number of graphical interfaces for analysis with LabVIEW to provide the same
functionality as the existing lab. Because the circuits to be built and tested remain
unchanged, the graphical interfaces will serve the same objectives as the existing labs.
Finally, the team will write a detailed documentation for TAs or technicians in the
electrical engineering department on how to convert the existing electronics laboratory to
the one using ELVIS.
4.2 Technical Design
When reporting the actual design of the project, several major topics will be explained in
detail:
1.
2.
3.
4.
Working mechanism of ELVIS/LabVIEW
LabVIEW code and user interfaces
Capabilities and limitations of ELVIS
Lab conversion documentation
Working mechanism of ELVIS
As stated earlier, the ELVIS hardware is still a work in progress. This adds a measure of
difficulty to the work being done for this project. Every effort will be made to
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successfully complete this project without requiring modifications to the ELVIS
specifications.
The original project plan stated several existing EE 201 labs would be migrated to the
ELVIS system without fundamentally changing the concepts taught in lab and also to
remove the need for traditional instrumentation. Due to several limitations in the current
ELVIS hardware, this may no longer be an obtainable goal. For example, several EE 201
labs require students to measure current at certain points in their circuits. ELVIS does not
support current measurement. Either the fundamental concept of current measurement
will have to be removed, or a traditional instrument capable of current measurement will
need to be used.
In the final documentation outlining the procedure to convert labs to make use of ELVIS,
all inherent limitations of ELVIS must be clearly explained and alternative actions
provided.
LabVIEW and user interfaces
One of the primary advantages ELVIS has over traditional instruments is its data
acquisition capabilities. The virtual instruments provided by NI to control ELVIS do a
good job of recreating the look and feel of traditional instruments, but do little as far as
providing users with the ability to automatically record data.
Providing students with a method to visually observe circuit behavior through the use of
graphs, tables and charts would be a major advantage over traditional lab instruments. NI
has provided source code to the ELVIS virtual instruments. With the objective of adding
value to what ELVIS has to offer, the team will extend these virtual instruments to
include enhanced data capturing and visualization capabilities.
Capabilities and limitations of ELVIS
Through the course of this project, the team will document the enhanced capabilities of
ELVIS as they are developed and also make note of inherent limitations of the system as
they are discovered. An objective summary of all capabilities and limitations will be a
critical component of the final project report.
Those who are responsible for EE labs will base their decision whether or not to adopt
ELVIS in large part on the contents of this list.
Lab conversion documentation
The primary goal of providing lab conversion documentation depends mainly on actually
implementing the EE 201 labs using ELVIS. If the lab can be completed in a way that
meets the requirements and specifications of the project, the team will then document
what must be done to convert to using ELVIS.
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4.3 Testing Description
The user interface enhancements made to the ELVIS virtual instruments will need to be
tested. Because the initial development will based on EE 201 labs, current EE 201
students will be contacted and asked to evaluate the ELVIS system. The team will learn
what common mistakes they make and how the interface can be refined to prevent similar
mistakes in the future.
Finally, the document describing the lab conversion process will also need to be tested.
Testing shall consist of having the team follow the directions created for the project and
evaluate the effectiveness of the conversion instructions. If the conversion resulting from
following the directions is not exactly what the team intended, the documentation will be
revised.
4.4 Risks and Risk Management
1. The equipment is expensive. Special care must be taken in the installation process.
2. Provided with damaged or malfunctioning equipment from National Instruments.
3. A team member may be lost from the project. If this occurs, the only option will be to
finish the project with the remaining team members.
4. Delayed delivery of equipment from National Instruments.
One risk not taken into consideration earlier was that ELVIS might be fundamentally
insufficient for a college level lab environment. Some of the deficiencies may be
minimized or fixed later but for now this is a significant risk. Risk management has
otherwise progressed according to the original plan.
There is also a risk that other unknown deficiencies will be discovered in the future and
these may prevent the team from successfully completing the project.
4.5 Recommendation for Continued Work
Based on what the team has seen thus far of the capabilities of ELVIS, it is recommended
that the project be continued through to the completion. Barring unforeseen problems, it
seems likely that the project will be completed as designed. Reasons for this
recommendation include the ease of learning to use the ELVIS system and the high
degree of adaptability of EE 201 labs to the ELVIS system.
However, the lack of current measurement and the measurement inaccuracy of other
parameters are major issues. Several of the labs are not compatible with ELVIS because
they require current measurements. The EE 201 labs will either have to be modified or NI
will have to improve ELVIS. Assuming that both these problems will be rectified in an
upcoming version of ELVIS makes continuing this project worthwhile.
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5 Financial Budget
The hardware and software used in this project have been provided by National Instruments.
Thanks to the capabilities of the ELVIS system, no additional hardware will be required to
implement the lab conversion process. The only additional foreseeable cost will be a poster
used to describe the goals of this project to the public. Table 5.1 provides an itemized list of
foreseeable costs.
Table 5.1 – Financial Budget
Item
Materials provided by
National Instruments
Original Estimated Cost Revised Estimated Cost
Poster
$10,000
$10,000
$100
$70
6 Personnel Effort Budget
Table 6.1 shows the estimated number of hours each team member will spend on different
tasks throughout the course of this project. Actual time worked may deviate from these
estimates.
Table 6.1 – Personnel Effort Budget
Personnel
Michael
Ballou
Ryan
Hankins
Jason
Salz
David
Schmidt
Dayu
Zhou
Totals
Project
Planning
Orig.
Rev.
Project
Design
Orig.
Rev.
Interface
Development
Orig.
Rev.
Interface
Test
Orig.
Rev.
Project
Documentation
Orig.
Rev.
15
15
25
15
40
40
10
10
25
2
2
20
11
45
55
15
15
5
5
20
5
45
55
15
15
15
25
10
40
40
4
4
20
10
50
41
41
110
51
220
Totals
Orig.
Rev.
25
115
105
20
20
102
103
15
20
20
105
100
10
10
30
30
120
105
50
15
15
20
20
109
99
240
65
65
115
115
551
512
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7 Project Schedule
The project will span the course of two semesters, beginning in mid September and ending in
early May. The planning phase of this project will proceed from the start of the project until
mid December. The development phase of the project will begin in mid January and continue
through the end of March. Upon successful completion of development and test verification,
a post implementation review will be conducted followed by a final project demonstration
and report. See Figure 7.1 for an itemized account of all scheduled tasks.
Figure 7.1 – Project Schedule
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8 Project Team Information
 Client:
National Instruments
11500 N Mopac Expwy
Austin, TX 78759-3504
David Gardner
512-683-5458
Fax: 512-683-6837
david.gardner@ni.com
Randy Hoskin
512-683-0809
Fax: 512-683-5678
randy.hoskin@ni.com
 Faculty Advisors:
Mina, Mani
Office Address:
341 Durham
Ames, IA 50011-2252
Office Phone: 515-294-3918
Fax: 515-294-8432
mmina@iastate.edu
Rover, Diane
Office Address:
3227 Coover
Ames, IA 50011-3060
Office Phone: 515-294-7454
drover@iastate.edu
 Group Members:
Ballou, Michael
3336 Frederiksen Ct
Ames, IA 50010
515-572-8077
michaelb@iastate.edu
Computer Engineering
Hankins, Ryan
1318 Woodstock
Ames, IA 50014
515-292-5135
rhanks@iastate.edu
Electrical Engineering
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Salz, Jason
1551 Helser MacDonald
Ames, IA 50012
515-572-2755
wombat7@iastate.edu
Electrical Engineering
Schmidt, David
3336 Frederiksen Ct
Ames, IA 50010
515-572-8077
schmidtd@iastate.edu
Computer Engineering
Zhou, Dayu
212 N Franklin Ave
Ames, IA 50014
515-292-2165
xinyu@iastate.edu
Electrical Engineering
9 Summary
The key to completing this project is the proficiency of the group members to utilize ELVIS
and LabVIEW. Many hours will be spent simply learning the quickest and most efficient
techniques to operate these systems. Once this is accomplished, it should not be difficult to
replicate the work done currently in the labs with the virtual instruments. With the successful
conversion of a lab completed, compiling notes into a document that can be referenced to
convert similar labs should not be difficult, either. The crucial key to the entire project is a
solid knowledge base of how ELVIS and LabVIEW work.
10 References
http://digital.ni.com/demo.nsf/websearch/8B0D55401472DDDE86256AB90077DB80
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