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Nov 15, 2013 (3 years and 4 months ago)

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Multidisciplinary Engineering Senior Design

Project 6508 Controls Lab Interface
Improvement

Critical Design Review

2/24/05

Project Sponsor: EE Department


Team Members: Michael Abbott, Neil Burkell


Team Mentor: Dr. Mathew, Dr. Sahin


Coordinator: Dr. Phillips





Kate Gleason College of Engineering

Rochester Institute of Technology

Project Overview


Current Controls Lab:


Current System used was purchased from Feedback
for use in the Controls Lab which included Analog and
Digital Control Boards to be used with a DC Motor.


System was designed for technicians not students


The Digital Board is outdated


Past work from a student Ruben Mathew has shown
the digital board does not work

Project Overview


Current Controls Lab:


Digital control is taught through Simulink from varying
sampling time and using different methods for
converting continuous to discrete transfer functions








There are no hardware experiments using digital
controllers


A new Digital Board is needed for the lab



Project Overview


Needs for the Controls Lab:


Need to use Simulink on Lab PC


Need to use current Feedback 33
-
100 DC Servo
Motor and Power Supply


The new digital interface must link Simulink
to the existing DC motor


Exploration into feasible interface concepts
was needed (SD I deliverable)


Needs Assessment


System must interface Simulink to the motor


Capture experimental results accurately


User friendly for the students


Change sampling time easily for student learning


Use existing equipment


Be expandable for future labs or projects


Have a finished product by the end of Winter quarter


Protected from students but also be accessible to be
fixed

Requirements Developed


The Requirements of the Project are as follows:


Interface MATLAB/Simulink with the servo DC
motor


Simulink block diagram will control the servo DC
motor


Sampling time easily changeable from 1 ms to
300 ms


Interface will return real time data and output real
time signals


Interface will have 4 additional digital
inputs/outputs, 1 additional analog output, and 7
differential analog inputs

Requirements Developed


The Requirements of the Project (continued)


Interface will acquire motor speed and position
data


Analog inputs: resolution of 16 bits, range of
+10V to
-
10V.


Analog outputs: resolution of 16 bits, range of
+10V to
-
10V.


Interface will be covered


Use the existing Feedback Power Supply



Overall System Diagram

Lab PC

with Matlab

and Simulink

System


Interface

Feedback

33
-
100

DC Servo Motor

Feedback

Power


Supply

Gnd, +
-
15V, 5V

Analog to Motor +
-
8V to PA(+ve,
-
ve)

Digital from Motor 6 Grey Code + Index
for Position

Analog from Motor Tachogenerator +
-
8V

Communication

PA +ve, PA

ve,
Tachogenerator +
-
, Grey code
Position idicator

Mechanical Unit 33
-
100

Input Shaft

Output Shaft

Tachogenerator

MATLAB Software Layout

Analysis & Synthesis of Design


Multiple Concepts were developed

1)
Using a DSP Development Kit

2)
Using a USB Data Acquisition Board


Importing Simulink diagram into NI LabVIEW

3)
Data Acquisition PCI Card in Windows

4)
Separate PC with I/O Capability controlled by
MATLAB

Analysis & Synthesis of Design


Concept 1: Using a DSP Development Kit

Simulink

DSP Kit

Interface Board

Motor


Concept 2: Using a USB DAQ Board

Simulink

DAQ Board

Interface Board

Motor

USB

USB

RS232


Both concepts found not to be feasible

Analysis & Synthesis of Design


Concept 3: PCI DAQ Card

Simulink

PCI DAQ

Interface Board

Motor


PCI Card meets all requirements for I/O’s


PCI Card is supported by Simulink and Real Time
Workshop


Runs Inside the Windows Environment


No additional software would need to be purchased


Additional breakout hardware would be necessary


System Interface would not be portable


Measurement Computing PCI Card has best value

Ethernet

RS232


PCI Card meets all requirements for I/O’s


PCI Card is supported by Simulink, Real Time
Workshop, and xPC Target


Runs external from the Windows Environment


Additional breakout hardware would be necessary


System Interface would be portable


Measurement Computing PCI Card has best value

Analysis & Synthesis of Design


Concept 4: Separate PC with PCI DAQ Controlled by
MATLAB

Simulink

Computer

Interface Board

Motor

PCI DAQ

System Diagram


Both concepts use the Real Time Workshop in MATLAB

System Block Diagram

Real Time

Workshop

Simulink

Generated C

Code

Real Time

Workshop

DC Motor

PCI Card

Generated C

Code

xPC Kernel

PCI Card

Computer

Real Time Windows Target Toolbox

xPC Target Toolbox

Interface

Board

Second Computer

Simulink

DC Motor

Interface

Board

Computer

PCI DAQ Card


Measurement Computing PCI Card


16 Analog Inputs


2 Analog Outputs


24 Digital Inputs or Outputs

Gantt Chart Followed

Events
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Week 9
Week 10
Week 11
Receive Software
Receive Parts
Learn xPC Target Toolbox
Learn RTW Target Toolbox
Interface Hardware and Simulink
using xPC and RTW
Debug
Design PCB Interface Board
Impliment Test Plan
Demonstration
Documentaion of xPC and RTW
Order Additional Lab Setups
Winter Quarter 05-06
Desired Outcomes




A complete working digital control system:


Interfaces with Simulink


Not dependant upon software versions


Simple to use


Can be used in other applications


Desired Outcomes




Compare the differences between using PCI
DAQ Card and external computer with PCI DAQ
Card


From transient testing for the Control System Design
Class


Using a more computationally intensive controller
(Fuzzy Logic Controller) to see where each system
fails

Desired Outcomes




Document the process for developing digital
controllers to be able to implement them in a
laboratory setting


Key Requirements

1)

Show that data can be acquired and output at the minimum
sampling time of
0.001 seconds

at the
maximum range of

±
10
V



2)

Use interface board, Feedback Mechanical Unit 33
-
100,
Feedback power supply, and Simulink Control Algorithm to
control the speed

of the motor.


3)

Use interface board, Feedback Mechanical Unit 33
-
100,
Feedback power supply, and Simulink Control Algorithm to
control the position

of the motor.


4)

Documentation, including a
user guide
, working
Simulink
models
, and a
service manual
.

Critical Parameters

1.
Acquire 20 V peak to peak, 100 Hz sine wave using digital
interface and output. Verify with oscilloscope.


Input Wave

Output Wave

Critical Parameters

2.
Velocity control of motor to a reference of 1.5 V (600 RPM)
recorded on both an Oscilloscope and by MATLAB


Transient Results include Rise Time, Overshoot, Peak Time


step
y
M
OS
ss
pt


Critical Parameters


Use a Simulink Integrator Controller


Verify:

-
Tachogenerator voltage 1.5 V
±

5%






Step
1
s
Integrator
5
Gai n
0.5
Constant
Anal og
Output
Anal og Output
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input
Measurement Computing
PCI-DAS1602-16 [auto]
Add1
Add
10

11

12

13

14

15

16

17

18

19

20

0

0.5

1

1.5

time [sec]

Tachometer Voltage [V]

Results for Integrator Controller

SIMULATION
RESULT

Tachogenerator
Voltage from
Motor

Power Amplifier
on Motor

Critical Parameters


Use a Simulink PI Controller


Verify:

-
Tachogenerator voltage
1.5 V
±

5%




-
Transient Results within
±

5%








s+6.5
s
Transfer Fcn
Step
2.5
Gai n
0.5
Constant
Anal og
Output
Anal og Output
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input
Measurement Computing
PCI-DAS1602-16 [auto]
Add1
Add
10

11

12

13

14

15

16

17

18

19

20

0

0.5

1

1.5

time [sec]

Tachometer Voltage [V]

Results for Integrator Controller

SIMULATION
RESULT

Tachogeneartor
Voltage from
Motor

Power Amplifier
on Motor

Critical Parameters


Use a Simulink One Pole Controller


Verify:

-
Tachogenerator Voltage within
±

5%



Theoretical Steady State Error




-
Transient Results within
±

5%




1
s+5
Transfer Fcn
Step
20
Gai n
0.5
Constant
Anal og
Output
Anal og Output
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input
Measurement Computing
PCI-DAS1602-16 [auto]
Add1
Add
10
11
12
13
14
15
16
17
18
19
20
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
Results for One Pole Controller
SIMULATION
RESULT

Tachogenerator
Voltage Output
from Motor

Power Amplifier
on Motor

Critical Parameters

3.
Position control of motor output shaft from a initial value of
270 degrees to 90 degrees


Use a Simulink Feedback Controller


Verify:

-
Transient results within
±

5% of analog control


1
Gai n
Anal og
Output
Anal og Output
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input1
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input
Measurement Computing
PCI-DAS1602-16 [auto]
Add
0
1
2
3
4
5
6
7
8
9
10
-10
-5
0
5
time [sec]
Position Voltages [V]
Feedback Position Results (Motor Initially at 270 degrees and moved to 90 degrees)
Output Shaft Voltage
Input Shaft Voltage
Input Shaft
Voltage from
Motor

Output Shaft
Voltage from
Motor

Critical Parameters

4.
Documentation:



Include all Simulink diagrams used in testing


Step by step user guide on how to setup both xPC and RTW Target
toolboxes and systems


Full system design including part numbers, PCB layout files, and
schematics of Feedback system


s+6.5
s
Transfer Fcn
Step
2.5
Gai n
0.5
Constant
Anal og
Output
Anal og Output
Measurement Computing
PCI-DAS1602-16 [auto]
Anal og
Input
Anal og Input
Measurement Computing
PCI-DAS1602-16 [auto]
Add1
Add
PCB LAYOUT

Simulink Diagram

Test
Points

PCI
Connectors

Motor
Connector

Major Design Challenges


Documentation on Feedback System was
lacking


Traced servo DC motor board and analog board to
develop schematics to understand the different
signals



Establishing control of the servo DC motor with
results similar to the analog controller


Preliminary testing using breakout box and wires with
sockets verified the correct signals needed


Major Design Challenges


Understanding and using Real Time
Workshop using xPC Target Toolbox and
Real Time Windows Target Toolbox


Read manuals on both toolboxes and performed
tutorials



Noise when reading sensor data from the
servo DC motor board


Traced to Feedback switching power supply


Noise eliminated when using HP power supply
currently in lab


Interface Design


-
Interface connections needed








Motor Board



5 Analog Sensors

1 Analog Input

6 Digital Outputs


PCI DAQ Card



6 Analog Inputs

1 Analog Output

6 Digital Inputs


Interface Board


Analysis of Design


Failure Analysis was done for the
system


Measurement Computing contacted to find
absolute max ratings for PCI card


Maximum input/output voltages of
Feedback system investigated


Motor board and PCI card were determined
to be safe from damage


Analysis of Design


Safety codes were investigated


OSHA code that applies:

Guarding of live parts.

1910.303(g)(2)(i)


Except as required or permitted elsewhere in this subpart, live parts
of electric equipment operating at 50 volts or more shall be guarded
against accidental contact by approved cabinets or other forms of
approved enclosures, or by any of the following means:



Highest rated voltage on interface board is 30 V


Design safe for laboratory setting

Final Design


-
Interface board is redesigned with the previous
connections but with different test point locations
and additional pads in case extra circuitry is desired




-
Larger holes will be designed into the interface
board to be able to put a Plexiglas cover


Final Design

-
For Control Design Lab Real Time Windows Target Toolbox meets
the criteria for all controllers that would be implemented

-
For other higher level classes the xPC Target Toolbox should be
utilized (Fuzzy Logic, Modern Control, Signal Processing, etc)



Computer

Computer

RS
-
232

PCI Card

PCI Card

Interface

Board

Interface

Board

Motor

Board

Motor

Board

Computer

PCI Card

Interface

Board

Motor

Board

Two Computer Solution

One Computer Solution

Testing Results


Integrator Results




Control Algorithm
OS (%)
% Error OS
T
r
(sec)
% Error T
r
T
p
(sec)
% Error T
p
Integrator Controller (Analog)
38.10
6.46
0.68
7.94
1.09
4.78
Integrator Controller (RTW)
39.60
2.77
0.65
3.17
1.06
1.89
Integrator Controller (xPC)
39.48
3.07
0.64
1.59
1.06
1.89
Integrator Controller (Simulation)
40.20
1.30
0.66
4.76
1.09
4.59
Integrator Controller (Theoretical)
40.73
---
0.63
---
1.04
---
10
11
12
13
14
15
16
17
18
19
20
-1.5
-1
-0.5
0
0.5
1
1.5
2
time [sec]
Tachometer Voltage [V]
Results for Integrator Controller (Results Shifted for Viewing Purposes)
Analog Control Board Result
Simulation Control Result
Digital Control MATLAB Real Time Windows Result
Digital Control MATLAB xPC Target Result
step
y
M
OS
ss
pt


Testing Results


PI Controller Results





Control Algorithm
OS (%)
% Error OS
T
r
(sec)
% Error T
r
T
p
(sec)
% Error T
p
PI Controller (Analog)
24.30
3.57
0.27
3.85
0.46
2.68
PI Controller (RTW)
25.80
2.38
0.27
3.85
0.47
3.79
PI Controller (xPC)
25.35
0.60
0.26
0.00
0.46
2.68
PI Controller (Simulation)
25.20
---
0.26
---
0.45
---
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
-1.5
-1
-0.5
0
0.5
1
1.5
2
time [sec]
Tachometer Voltage [V]
Results for PI Controller (Results Shifted for Viewing Purposes)
Analog Control Board Result
Simulation Control Result
Digital Control MATLAB Real Time Windows Result
Digital Control MATLAB xPC Target Result
step
y
M
OS
ss
pt


Testing Results


One Pole
Controller Results





Control Algorithm
OS (%)
% Error OS
T
r
(sec)
% Error T
r
One Pole Controller (Analog)
27.03
8.68
0.35
4.48
One Pole Controller (RTW)
28.01
5.37
0.35
4.48
One Pole Controller (xPC)
28.10
5.07
0.35
4.48
One Pole Controller (Simulation)
27.03
8.68
0.35
4.48
One Pole Controller (Theoretical)
29.60
---
0.34
---
T
p
(sec)
% Error T
p
V
ss
(V)
% Error V
ss
One Pole Controller (Analog)
0.55
5.83
1.2150
3.61
One Pole Controller (RTW)
0.54
4.85
1.2186
3.92
One Pole Controller (xPC)
0.54
4.85
1.2158
3.68
One Pole Controller (Simulation)
0.54
4.85
1.1728
0.01
One Pole Controller (Theoretical)
0.52
---
1.1727
---
10
11
12
13
14
15
16
17
18
19
20
-1.5
-1
-0.5
0
0.5
1
1.5
Time [sec]
Tachometer Voltage [V]
Results for One Pole Controller (Results Shifted for Viewing Purposes)
Analog Control Board Result
Simulation Control Result
Digital Control MATLAB Real Time Windows Result
Digital Control MATLAB xPC Target Result
step
y
M
OS
ss
pt


Testing Results


Two Pole, One Zero
Controller Results





Sampling Time [sec]
0.0250
0.0375
0.0500
0.1000
0.2000
Simulation OS [%]
15.000
19.900
24.600
39.800
--
Single Computer [% Error]
3.000
2.010
2.439
3.015
Two Computer [%Error]
0.667
1.508
1.626
3.769
Simulation T
r
[sec]
0.429
0.430
0.413
0.410
--
Single Computer [% Error]
0.233
3.488
3.030
6.098
Two Computer [% Error]
3.263
1.163
0.606
7.317
Simulation T
p
[sec]
0.600
0.610
0.625
0.650
--
Single Computer [% Error]
0.000
0.000
0.000
0.000
Two Computer [% Error]
0.000
0.000
0.000
0.000
0
2
4
6
8
10
12
14
16
18
20
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
Time [s]
Tachogenerator Voltage [V]
RTW Target Step Response for Different Sampling Times with ZOH Equivalent Discrete Controller
0.0375 Sampling Time
0
2
4
6
8
10
12
14
16
18
20
-3
-2
-1
0
1
2
3
4
Time [s]
Tachogenerator Voltage [V]
RTW Target Step Response for Different Sampling Times with ZOH Equivalent Discrete Controller
0.2 Sampling Time
Testing Results


Position Control
Results






0
1
2
3
4
5
6
7
8
9
10
-10
-5
0
5
time [sec]
Position Voltages [V]
Feedback Position Results (Motor Initially at 270 degrees and moved to 90 degrees)
Output Shaft Voltage
Input Shaft Voltage
0
1
2
3
4
5
6
7
8
9
10
-10
-5
0
5
Analog Board Feedback Position Results (Motor Initially at 270 degrees and moved to 90 degrees)
time [sec]
Position Voltages [V]
Output Shaft Voltage
Input Shaft Voltage
Output Shaft

Input Shaft

Testing Results


Power Supply Noise Results






10
11
12
13
14
15
16
17
18
19
20
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
time [sec]
Tachometer Voltage [V]
Plot of Tachometer Voltage vs. Time for Different Power Supplies (Shifted for Viewing Purposes)
HP E3631A Power Supply
Feedback 01-100 Power Supply
Testing Results


Fuzzy PI Controller Implementation
Performance Comparison






Sampling
Frequency
Single Computer
Experiment: Processor
Percentage
Two Computer
Experiment: Task
Execution Time
1 kHz
4%
49
μs
2 kHz
7%
50
μs
4 kHz
14%
53
μs
8 kHz
29%--Stopped Running
51
μs
10 kHz
Stopped Running
Immediately
54
μs
Conclusions


-
Both designs successful

-
Both can be used in Current Control Systems
Design Lab

-
Two Computer Setup can be used in multiple
applications




Computer

Computer

RS
-
232

PCI Card

PCI Card

Interface

Board

Interface

Board

Motor

Board

Motor

Board

Computer

PCI Card

Interface

Board

Motor

Board

Two Computer Solution

One Computer Solution

Thank You

Dr. Phillips

Dr. Mathew

Ken Snyder

Jim Stefano

Jacob Slezak

Questions

?

Item
Itemized Cost
Qty.
Total
Interface PCB (3 min. order)
$17.00
1
$17.00
50 Pin Connector
$1.47
2
$2.94
34 Pin Connector
$1.14
1
$1.14
PCI-DAS1602/16
$715.50
1
$715.50
C100FF-2 (50 Pin Ribbon Cable)
$44.10
1
$44.10
Total Cost Per Station
$780.68
Complete Lab Station
$780.68
8
$6,245.44
Single Computer Setup BOM

Two Computer Setup BOM

Item
Itemized Cost
Qty.
Total
Interface PCB (3 min. order)
$17.00
2
$34.00
50 Pin Connector
$1.47
4
$5.88
34 Pin Connector
$1.14
2
$2.28
PCI-DAS1602/16
$715.50
2
$1,431.00
C100FF-2 (50 Pin Ribbon Cable)
$44.10
2
$88.20
RS-232 Cable
$8.00
1
$8.00
xPC Target License (One Year for
Entire Lab)
$600.00
Total Cost Per Pair
$1,569.36
Total Cost for Lab (Hardware)
$1,569.36
4
$6,277.44
Total Cost for Lab with Software
$6,877.44
Production Plan

Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Order PCI Card from
Measurement Computing
Receive PCI Cards
Install PCI Cards into PC's
Order PCB Boards
Receive PCB Boards
Populate PCB Boards
Test Setups