LAB 7 STEPPER MOTOR CONTROL

write for me an introduction,material list,procedure. I’ve attached a sample that you can follow,a lab report report,and the lab itself. do report for lap#7
lab07_stepper_motor_control.pdf

example_lab_report_writeup__1_.pdf

Don't use plagiarized sources. Get Your Custom Essay on
LAB 7 STEPPER MOTOR CONTROL
Just from $13/Page
Order Essay

lab_report_guide_1_.pdf

Unformatted Attachment Preview

Mechatronics
Spring 2018
LAB 7 STEPPER MOTOR CONTROL
OBJECTIVE
•
•
•
Learn what stepper motors are and how they work.
Learn to interface stepper motors to the Arduino motor shield.
Program in MATLAB to control the stepper motion.
INTRODUCTION
I.
Stepper Motors
Stepper motors are a special kind of motor designed to move in discrete steps. This can perhaps
best be understood by looking at how they are designed. While there are many variations, you
will get the general idea by studying a simple type of stepper called the permanent magnet
stepper. Consider the diagram below. The stepper rotor is the moving part attached to the shaft.
It is a permanent magnet with North (N) and South (S) poles. The stepper stator surrounds the
rotor and is the stationary part of the motor. It consists of several coils of wire wound around
iron laminations, which make up electromagnets that can be turned on and off. Recall that
opposite magnetic poles (i.e. N-S) attract each other while like poles (N-N and S-S) repel. The
magnetic polarity of the stator magnets can be controlled, by controlling the current direction
through the coils.
coil A
coil A
coil B
S
N
coil D
coil D
coil B
S
N
coil C
coil C
Figure 1A: rotor aligned with coil A Figure 1B: rotor aligned with coil B
Fig.1. a. Rotor Aligned with Coil A (left), b. Rotor Aligned with Coil B (Right)
Let us assume that our stepper is set up so that when we turn a coil “on” it generates a magnetic
N pole closest to the rotor. Then, if we turn on coil A and leave all of the others off, it is clear
that the rotor will try to line itself up with its S pole aligned with coil A, as shown in Figure 1a.
If we leave coil A on, the rotor will come to rest in alignment with coil A and will not move
farther. In fact, it will vigorously resist any attempt to manually move it from this position. The
amount of external torque the motor can resist is called its holding torque.
Page 1 of 4
Mechatronics
Spring 2018
If we then turn off coil A and turn on coil B, the rotor will turn
¼ rotation to the right and align with coil B, as shown in Figure
1b. Continuing to rotate the magnetic field around the circle
will cause the rotor to align next with coil C then coil D, etc.
Each of these locations is a stable position. That is, as long as
one of the coils is energized, the rotor will attempt to lock itself
in alignment with that coil.
The motors you will use are wound as shown in Figure 2. The
motors have two coils (i.e. two phases), each with a center tap,
allowing you a great deal of flexibility in how the motors are
controlled.
Fig. 2. Stepper Motor Windings
with Center Tap
PROCEDURE
I.
Windings
Your first task is to figure out how the stepper motor used in
the lab (Figure 3) is wired. Use your ohmmeter (digital multimeter) to find which colored wires are connected to each coil in
the stepper motor. You will find that the wires are connected in
groups of three, as you can see from the diagram in Figure 2.
First separate the wires into their groups of three and write
down the colors for Group A-B-C and Group D-E-F. You
should be able to find which wire corresponds to terminal A
and which one is terminal D in Figure 2 by comparing the
resistances between the different wires. The resistance between
Fig. 3. Stepper Motor in the Lab
wire C and wire B will be twice as much as the resistance
between C and A or A and B. The same method works for group D-E-F. Write down the wire
colors for terminals A and D.
Find wires A and D and connect them both to the ground. From coil A-B-C, connect one of the
wires to +5V. The motor will move to an equilibrium position and stop. Label that wire B, and
the other wire from that group C. Now with wire B still connected to +5V, choose one of the
wires from the other group and connect it also to +5V. Note which direction the motor turns
when you do this. For the sake of convention, if the motor turns CCW when you connect the
second wire, call it wire E and if the motor turns CW, call it wire F. Label the remaining wire
accordingly. The stepping sequence will be B, E, C, F for CCW rotation, and B, F, C, E for CW
rotation.
Connect wires B, C, E, F to the A+, A-, B+, B- terminals on the Arduino Motor Shield, do not
connect wires A and D to anything, and power the shield with a +5V power supply. Since we are
using the Arduino Motor Shield for motor control, the shield’s pins, divided by channels are
shown again in the table in the next page:
Page 2 of 4
Mechatronics
Spring 2018
Function
Direction
Voltage
Brake
Current Sensing
Pins Per Ch. A
D12
D3
D9
A0
Pins Per Ch. B
D13
D11
D8
A1
For example, if we want to switch the terminal ‘A-’ to ‘high’, we need first send a digital output
command to pin D12 to select the proper direction, and then send another digital output
command to D3 to turn it on. This is not a very straightforward process and you might need to
try a few times to get it right. The good news is that there is an LED connected to each of the A+,
A-, B+, B- terminals on the Arduino Motor Shield, so you can try different commands and see if
you can turn on the associated LED in a proper sequence.
To turn the motor CCW four steps would require the following sequence (pseudocode). Note that
this sequence uses only one coil at a time.
1. Set A+ terminal high, all others low; Hint: this step will take three lines of code.
2. pause(0.5)
3. Set A+ terminal low
4. Set B+ terminal high, all others low
5. pause(0.5)
6. Set B+ terminal low
7. Set A- terminal high, all others low
8. pause (0.5)
9. Set A- terminal low
10. Set B- terminal high, all others low
11. pause (0.5)
12. Set B- terminal low
The sequence shown above could be repeated until enough steps had been taken. Each switch of
the coils requires a short pause between steps to allow the rotor to move before issuing a new
step command. Play with the length of pause to see how short you can make it.
II. Forward and Reverse Motion
Determine the number of steps per revolution of your motor, then write a program that will drive
the motor one revolution clockwise and one revolution counterclockwise. Use the full-stepping,
one coil at a time mode. Put a piece of tape on the motor shaft as a “flag” to help you see how
far the shaft has gone. Start by making a flow chart of your programming logic for making the
program work.
Hint: Do not forget to turn off the coils at the appropriate times. Also, do not forget that it will
take some time for the stepper to move from one point to another, and that it will move much
slower than the computer can run through the program. You must insert some time delay in the
appropriate places or the motor will not be able to keep up. If the motion is erratic or it appears
Page 3 of 4
Mechatronics
Spring 2018
that steps are being skipped, you either have the coils out of sequence or you need to insert more
time delay.
Demonstrate your program to a TA before going on to the next step.
III. Input from Keyboard
For motion control, we want to be able to tell the motor when to stop and which direction to go
from a program or perhaps from the keyboard. Let’s use the keyboard as our input interface.
MATLAB can accept input from the keyboard via the command input(‘prompt’). From
the Matlab command window, type help input for more information on this command.
Modify your first program to prompt the user for a number n between -40 and 40, and use this
number to drive the motor that number of steps in the forward (e.g. n > 0) or reverse (e.g. n < 0) directions, correspondingly. Hint: it’s easier to request the input number be a multiple of 4. Hint: you can set up your code with a structure like this: numsteps = input(‘Please enter the number of steps as a multiple of 4, using positive numbers for CCW and negative numbers for CW:’) if numsteps is a positive number for j = 1:1:(numsteps/4) run motor CCW 4 steps end elseif numsteps is a negative number for j = -1: -1: (numsteps/4) run motor CW 4 steps end end Demonstrate your program to a TA before going on to the next step. IV. Calibration In the real world, we deal in engineering units like millimeters and degrees, not in “steps”. Modify your program so the user is prompted to enter the number of degrees to move, with the limit between -180? and +180?. Insert a math statement in the code to convert the input to a number of steps for your program. Demonstrate your program to a TA before cleaning up your lab station. DELIVERABLE Submit a lab report to eCampus for your stepper motor experiments. Attach your MATLAB code (properly commented) as Appendix in the report. Page 4 of 4 MAE 211 Mechatronics Spring 2018 Laboratory 3: Digital Multi-Meter Larry Banta (LB) and Yu Gu (YG) Tuesday Lab Section, Station 19 February 07, 2018 1. Introduction The objective of this lab is to learn how to use the Digital Multi-Meter (DMM). The lab also provides instruction in writing up lab reports and presenting data. Although other exercises were performed in the lab, only the results of resistor testing will be presented here in this sample report. In your report, all experiments need to be discussed. 2. Materials List The lab station was supplied with a DMM and five (5) resistors, each with a nominal value of 1kO. The lab station had two lab partners, LB and YG. The only equipment used for this lab was a Cen-Tech Digital Multi-meter, model P37772. 3. Procedure The five resistors were laid out on the table in order so they could be distinguished from each other by position. They were labeled “A”, “B”, “C”, “D”, and “E” for data recording purposes. With the DMM on the 2kO scale, LB measured each of the resistors three times and recorded the data. Measurements were made by placing the resistor on the lab table and touching each end of the resistor with the meter probes, as shown in Figure 1. Figure 1: Resistance measurement method 1 1 A second set of measurements was then made by another person (YG), using a different method. He squeezed the resistor leads between his fingers and the meter probes, as shown in Figure 2. Three measurements were taken for each resistor. Figure 2: Resistance measurement technique #2. Finger pressure was used on both resistor leads Following those measurements, a different DMM was obtained by trading with another lab group. The purpose was to determine the influence of the meter on the readings. The same procedure was used with the second meter. Data from the experiments are presented in the next section of this report. 4. Results Data are presented below for each of the measurements taken. Table 1 presents data taken with Meter #1, and includes the data for both measurement methods. Table 2 presents the data taken using Meter #2. Table 3 is a summary of the data, and is constructed by taking the mean value for each set of three measurements on each resistor. 2 Table 1: Meter 1 Measurements Resistor Meter 1 LB (Ohms) Meter 1 YG (Ohms) mean sigma A 985 985 985 983 983 982 984 1.33 B 993 992 993 991 991 991 992 0.98 C 982 982 982 980 980 980 981 1.10 D 984 984 983 983 982 982 983 0.89 E 985 984 985 983 984 983 984 0.89 mean 986 985 986 984 984 984 sigma 4.21 3.85 4.34 4.12 4.18 4.28 mean sigma Table 2: Meter 2 Measurements Resistor Meter 2 LB (Ohms) Meter 2 YG (Ohms) A 983 983 983 979 979 980 981 2.04 B 991 992 991 987 987 988 989 2.25 C 980 981 980 977 977 978 979 1.72 D 983 982 983 979 979 979 981 2.04 E 984 984 985 980 980 980 982 2.40 mean 984 984 984 980 980 981 sigma 4.09 4.39 4.10 3.85 3.85 4.00 Table 3: Data Summary from Tables 1 and 2 A Meter 1 LB Average 985 Meter 1 YG Average 983 Meter 2 LB Average 983 Meter 2 YG Average 979 B 993 991 991 987 C 982 980 980 977 D 984 982 983 979 E 985 983 984 980 mean 986 984 984 981 sigma Overall Average Overall sigma 4.12 4.18 4.17 3.89 Resistor 984 4.20 3 5. Conclusions Although all five resistors were nominally 1,000 Ohms, the mean value of our measurements was 984 Ohms, as shown in Table 3. While this is within the ±5% tolerance of the resistor, it is interesting that all five of our resistors were less than the nominal value by a substantial amount. Four of the five resistors were within one standard deviation of the mean value. For a given meter, measurement method and resistor, there was very little variation in the measured values among the three measurements made in each trial. This indicates that there was not significant random electrical noise present in the readings. We wish to investigate the error mechanisms and the relative importance of several types of error on the measurements. We can model a single measurement as follows: Rm = Rt + ßm + ßp + e(t) (1) Where Rm is the measured value, Rt is the true value, ßm is bias due to the meter (constant), ßp is bias due to the measurement technique (assumed more or less constant, or at least containing a constant component) and e(t) is a random error that changes with each measurement and/or with time. In the absence of specific knowledge about e, we will assume that the random error is normally distributed with zero mean. We would like to estimate the bias terms, so that we can “correct” the measured data and develop an estimate of the actual resistance for each resistor. For the meter bias, we see that there is a difference in the readings between meter 1 and meter 2 of about 1.27 Ohms for LB and about 3.27 Ohms for YG. The person/method bias between LB and YG is about 1.73 Ohms for Meter 1 and about 3.73 Ohms for Meter 2. Similarly, the person/method bias is also dependent on the meter. Table 4 summarizes the calculations for the two bias errors. Table 4: Individual and Average Bias Errors (Ohms) LB Meter 1 - Meter 2 bias 1.27 YG Meter 1 - Meter 2 Bias 3.27 Average meter Bias 2.27 Meter 1LB - YG Bias 1.73 Meter 2 LB - YG Bias 3.73 Average User Bias 2.73 4 Our conclusion is that both the meter used and the measurement method used can have a measurable impact on the measured values of the resistors. It can be shown that the numbers given in Table 4 do not represent the actual biases, but rather the difference in bias errors between the two meters or the two methods. That is, the difference between the bias for meter 1 and for meter 2 is approximately +2.27O. But we do not know the absolute value of the bias for either meter. To determine the bias explicitly, we would need to compare the meter readings against a calibrated source. The person/method bias is also not known precisely, but the situation is slightly different in this case. We could declare one method or the other as the “standard” method, and so long as the standard is followed in all subsequent experiments, the results should be consistent. 5 MAE 211 Mechatronics Spring 2018 MAE 211 Mechatronics Lab Report Guide A. Introduction The purpose of this document is to illustrate for you the basic principles of report writing for the MAE 211 course. The instructions in this handout, if properly followed, will allow you to become proficient with what can be the challenging task of writing reports. Be aware that proficiency in technical writing is a critical capability for your future professional life. B. General Guidelines Some labs require that the overall format of the lab report be applied to several experiments. It is important to read over the lab guide to make sure your lab report contains all specified requirements designated for the lab report. It is important to note that when grading lab reports, length or wordiness of reports is not considered. As you are writing a technical report, it is imperative that your writing be complete, concise, and accurate, not necessarily lengthy. Each of your reports should fall somewhere between 37 pages, depending on the lab experiments and requirements. Font and paragraph formatting will not be limited, though it is important that your reports look professional and have reasonably-sized fonts and layouts. Your lab reports should be written to a person who is an engineer, but who is not familiar with the particular lab you are doing. Include enough detail that the reader can visualize your setup, assess your methods and understand clearly what you discovered. The write-ups are to demonstrate that you understand the objectives, methods, and outcomes of the experiments and should be done in your own words. Do not copy and paste sections of the lab instructions into your report. Generally, a laboratory report for MAE 211 should have the following sections. Exceptions will occur, but for most you should use the following outline as a template for your report. 1. Cover Page The cover page should be neatly formatted and include the name, number, and date of the lab, the lab section (e.g. Tuesday, Wednesday morning/afternoon, or Thursday), lab station number, and the names of all lab partners. 2. Introduction This should be a brief introduction to the lab or a particular lab experiment. It should have a concise statement of the objective of the experiment as well as any other pertinent information about the lab. 3. Materials List This section should be a listing of all the materials needed to complete the experiment. 4. Procedure This part of the report should lay out the procedure followed through the lab experiments, in your own words. You should also include drawings, schematics, or photographs as appropriate to tell the story. It is acceptable to write this section in either bullet/list format or paragraph format, as long as it completely recalls all steps taken during the lab. 5. Data Collected/Results This section should include all data collected in the lab as well as any results or findings of each experiment. This is where any questions asked during the lab or required results should be answered 1 MAE 211 Mechatronics Spring 2018 or explained. It is also important to state any reasons for your results not matching theoretical results or any inconsistencies with your data and possibly reasons for these inconsistencies. Illustrations or pictures taken during lab should be included here to help explain any setups created or results from experiments, and may be embedded directly in the text or referenced to an Appendix. 6. Conclusion This should be a conclusion stating the overall findings of the lab and how they relate to the lab objectives. Do not just report the values that we can all read in the Results section and do not introduce new results here. The Conclusions is where you interpret the data and provide your best explanation of what it all means. This could include some observations on how the experiment could have been improved, or some suggestions for additional measurement that could be taken in a later experiment. This does not have to be a book, but it does have to represent some thought and exhibit that you understand the principle involved. 7. Question In this section, answer with details any questions asked at the end of the lab guide. 8. Bibliography If references to external documents are used, they must be cited properly using “End-note” style and a bibliography must follow the Conclusions section. All lab reports must have a reference section. 9. Appendices Some lab reports may include significant amounts of data that would clutter the main body of the report, or lengthy computer programs that would detract from the flow of the document. Unless the program is the main deliverable for the lab, it should be placed in an Appendix. Voluminous data should be summarized by presenting graphs or statistics and the original data should be provided in an Appendix. In the report, pages must be numbered starting after the cover page. Figures/pictures must include captions with the number and title of the figur ... Purchase answer to see full attachment

GradeAcers
Calculate your paper price
Pages (550 words)
Approximate price: -

Why Work with Us

Top Quality and Well-Researched Papers

We always make sure that writers follow all your instructions precisely. You can choose your academic level: high school, college/university or professional, and we will assign a writer who has a respective degree.

Professional and Experienced Academic Writers

We have a team of professional writers with experience in academic and business writing. Many are native speakers and able to perform any task for which you need help.

Free Unlimited Revisions

If you think we missed something, send your order for a free revision. You have 10 days to submit the order for review after you have received the final document. You can do this yourself after logging into your personal account or by contacting our support.

Prompt Delivery and 100% Money-Back-Guarantee

All papers are always delivered on time. In case we need more time to master your paper, we may contact you regarding the deadline extension. In case you cannot provide us with more time, a 100% refund is guaranteed.

Original & Confidential

We use several writing tools checks to ensure that all documents you receive are free from plagiarism. Our editors carefully review all quotations in the text. We also promise maximum confidentiality in all of our services.

24/7 Customer Support

Our support agents are available 24 hours a day 7 days a week and committed to providing you with the best customer experience. Get in touch whenever you need any assistance.

Try it now!

Calculate the price of your order

Total price:
$0.00

How it works?

Follow these simple steps to get your paper done

Place your order

Fill in the order form and provide all details of your assignment.

Proceed with the payment

Choose the payment system that suits you most.

Receive the final file

Once your paper is ready, we will email it to you.

Our Services

No need to work on your paper at night. Sleep tight, we will cover your back. We offer all kinds of writing services.

Essays

Essay Writing Service

No matter what kind of academic paper you need and how urgent you need it, you are welcome to choose your academic level and the type of your paper at an affordable price. We take care of all your paper needs and give a 24/7 customer care support system.

Admissions

Admission Essays & Business Writing Help

An admission essay is an essay or other written statement by a candidate, often a potential student enrolling in a college, university, or graduate school. You can be rest assurred that through our service we will write the best admission essay for you.

Reviews

Editing Support

Our academic writers and editors make the necessary changes to your paper so that it is polished. We also format your document by correctly quoting the sources and creating reference lists in the formats APA, Harvard, MLA, Chicago / Turabian.

Reviews

Revision Support

If you think your paper could be improved, you can request a review. In this case, your paper will be checked by the writer or assigned to an editor. You can use this option as many times as you see fit. This is free because we want you to be completely satisfied with the service offered.

Order your essay today and save 15% with the discount code DISCOUNT15