1. California State University of Bakersfield
ECE 490A & 490B
Senior Seminar I & II
Pneumatic Conveyor Line Evaluation Robot
Author:
Joshua Duschen
Professor:
Dr. Wei Li
Date:
June 6, 2016
3. 1 Introduction
For our senior project we have been contracted by Bolthouse Farms to construct a robot the will be attached
to a pneumatic bottle conveyor. The robot will most likely be composed of an infrared proximity sensor or
photoelectric distance sensor that will utilized a PLC based program. The main purpose of this robot is to
follow along a pneumatic bottle conveyor and mark points along the conveyor that has deviated by 2mm. This
will allow the technicians to better trouble shoot the conveyor and determine whether or not the conveyor is
in need of repair, or replacement.
2 Problem
The reason Bolthouse Farms approached us is that they are having a great deal of trouble with their pneu-
matic bottle conveyors. Shown below in Figure 1 is a photo of said conveyor, it is a simple enough piece of
equipment composed of a few man parts. The conveyor is essentially made up of a neck guide, that guides
the bottles on their journey, and brushes, that stabilize the bottles. The issue lies within the neck guide, over
time the neck guide gets worn down by the constant ow of plastic bottles. At factory standards the neck
guide is to be approximately 36.5mm, technicians who work on the conveyor have determined that if the neck
guide deviates by 2mm or more, the conveyor will not work as desired.
Figure 1: Pneumatic bottle conveyor
2
4. Once the guide has widen by 2mm some bottles are able to slip through the guide and become wedge
into the conveyor, this then causes a build up of bottle that eventually leads to them falling. Not only does
this stop production but since the conveyor sits so high up in the air the falling bottles become a safety hazard.
The biggest issue that Bolthouse is experiencing is the amount of time it takes to trouble shoot this prob-
lem, they are attempting to locate a 2mm deviation in the conveyor by eye which is very time consuming.
The time it takes to identify the problem and change out the problem areas can take upwards of 6 hours, the
down time alone equates to a $10,000-$20,000 loss.
Sown in the table below is data taken from September 1st, 2015 until March 1st, 2016. There has been 66
instances in which the maintenance department has had to address issues with the pneumatic conveyor and
of those 66 instances 51 of them are due to jamming. In all, the conveyor has taken upwards of 27 hours of
the departments time.
It is our goal to be able to identify problem areas before hand to give the maintenance department a
chance to schedule the work to be done, rather than simply reacting. By being able to schedule the work,
the department can work on the conveyors when their is already scheduled down time so they do not have to
shut down the line in a an unexpected hurry.
Figure 2: Breakdown data
3
5. 3 Time Line
Week One- Identify the Design restrictions.
Week Three- Find a way that will allow us to be able to check the distances between the guides.
Week Five- Pinpoint the issues we want to resolve with this project.
Week Seven- Begin taking dimensions and drawing up specications.
Week Nine- Research the parts we will need to get our design together.
Week Ten- Initial design phase of the vehicle. Choose a design we will build during the second section of
senior seminar.
Week Fourteen- Completion of outer skeleton of our device, and begin designing the circuit.
Week Sixteen- Complete construction of a working prototype.
Week Eighteen- Trouble shooting working prototype.
Week Twenty- Project Completion.
4
6. 4 Material List
4.1 Mechanical Parts
• 6' of Aluminum
• 1-DC 12V 5000 RPM 6mm Shaft High Torque Gear-Box Electric Motor
• 1-12v Voltage Source
• 2-Plastic Enclosures
• 2-Worm Gears
• 4-Drive Gears
• 4-Drive Belts
• 4-Driven Pulleys
• 4-Following Pulleys
• 4-Idler Pulleys
4.2 Circuit Parts
• 1-1M Potentiometer
• 1-47k Ohm Resistor
• 1-22k Ohm Resistor
• 9-1k Ohm Resistor
5
8. • 1-H1L1 Optocoupler
• 1-4066 Quad Bilateral Switch
• 4-Standard LED
• 2-555 Timer
• 5-7 Segment Display
• 3-6v Battery Packs
• 1-12v Battery Pack
• 1-Encoder
Figure 3: DC 12V 5000 RPM Motor
The motor shown above in Figure 3 and the specs shown below in Figure 4 are simply a very generic
DC motor. This particular motor is reversible so it will allow the technician to double check a specic spot
if they feel it is necessary. This motor will also require a gearbox in order to achieve the correct speed. As
seen from the specs the motor is capable of 5000rpm but for our purposes we will need the rpm range to be
7
9. around 3500rpm. To attain that our gear ratio will likely be around 1.5.
Figure 4: Motor Specications
5 Design Procedure Senior Seminar I
5.1 Week 1- Week 5
It is our goal for the next few weeks to narrow down the types of sensors and designs we will utilize in the
conned space we have to work in. Because of the design of the conveyor we have very limited space above
the neck guide so we will likely make use of the room below by mounting our motor, sensor and power source
to the bottom of our device.
What we do know at this juncture is that our robot will require a PLC program to keep track of the
distance traveled and where the sensor detects potential problem areas. We decided to use a PLC because of
the high language programming, since we are not adept in programming we went with an easier interface.
We will either use plastic or aluminum components to cut down on the weight of our device so we do
not damage the conveyor. We also have to make sure that the robot is compact enough to t between the
neck guides snugly to allow for a stable travel. To accomplish this we will likely make use of V-grooved
wheels. Shown below in Figure 5 is the concept for the wheels we will likely be using. The specication
8
10. of the wheel shown below are arbitrary and will likely not match the dimensions of our actual wheels to follow.
Figure 5: V-Grooved Wheels
5.2 Week 6- Week 7
In weeks 1 through 5 we were still considering using plastic components but during our rst fabrication of
our devise we found that the plastic components were to malleable to be a usable material. It was clear that
the plastic wasn't going to keep its shape and would wear down far to quickly for what we needed it to do.
From here on out we have made the decision to use strictly aluminum materials to add strength and stability
but still not cause a strain on the conveyor.
We are still have been unable to determine what type of sensor we will be using. As of right now we
are leaning towards a proximity sensor. The idea was that we would program the sensor to constantly be
detecting within 2mm of the sensor and when ever it detected something outside that range we would know
that there was a bad spot in the conveyor. The benets of using a proximity sensor is that they are easy to
come by and are fairly cheap. Our only reservation is that we won't be able to accurately detect how much
the neck guide is worn down so that could make it dicult to determine what kind of work needs to be done
without taking a closer look at the section of the conveyor.
At this point we have come up with a rough idea on how we are going to design our robot. We gured we
would model the structure of the robot to that of a caterpillar, that is, we will have multiple parts connected
to each other but will still be able to pivot and take corners. Shown below is the rst mock up we drew to
9
11. get our ideas down on paper.
Figure 6: First design mock up
Shown in the gure above are rough specications we came up with about the sizing of the robot. This is
likely subject to change do to the size of the motor and sensor we will be attaching to it. The diameter of the
wheels however will stay that same because that is how much room we have to work with between the neck
guide.
Shown in the gure below is a very rough representation of how we will be attaching the wheels together.
We constructed this in a hurry in order to demonstrate our idea to the engineer at Bolthouse.
Figure 7: First prototype
10
12. Shown in the picture above it can be seen that the wheels are made out of plastic, it was when we fab-
ricated this rst design we discovered how malleable the plastic was. The idea of the wheels are to act as a
guide line for the robot to keep it snugly on the neck guide. We will also be adding wheels attached to the
top of the neck guide to hold the robot up the drive wheels will be below the neck guide to give it its movement.
5.3 Week 8- Week 10
From previous weeks we now have a pretty good idea of what our robot is going to look like and the speci-
cations of it's design. Shown below in Figure 6 is a comprehensive list of what the robot will be composed
of and the dimensions of said components. We have not been able to draw out where the sensor, motor and
power source will be located on the robot so we labeled the drawing accordingly.
The robot will contain a 12v DC motor as well as a 24v analog sensor, adding the weight of the drive
wheels, power source, and aluminum, we believe the weight of the robot will be around 15 pounds. The ideal
speed that the robot needs to operate at is just slightly over walking speed which is roughly 5mph, so to our
estimation the motor needs to be spinning anywhere between 1200rpm-3500rpm depending on the size of our
drive wheels. Another issue we have been trying to address is how we are going to stabilize the sensor.
In Figure 8 and Figure 9 it can been seen that the sensor will be mounted in the middle of the device. It
is likely that we will remove the center wheel and place the sensor there. One issue that we are experiencing
is that the sensor needs to remain perpendicular to the robot at all times in order to get an accurate reading
of the neck guide all the way through the track. To do this we plan on surrounding the sensor with a ball
bearing like cage in order to reduce friction and wear on the neck guide as our robot travels through the
conveyor.
On the programming side of our project the sensor we selected is easily programmed to detect at a certain
range, once it detects a bad spot in the track a light on the sensor will come on, this by default is how the
sensor works. For our purpose though we will have the sensor communicate with an encoder while the encoder
11
13. tracks how many feet the robot has traveled. This way the robot can determine exactly where there is a bad
spot on the conveyor.
Figure 8: Potential component make up (Drawn by Sean Barger)
12
14. Figure 9: Control System
The objective for our control system is to determine whether or not to change out the neck guide, our
sensor is to detect the wear on the neck guides and then notify the operator. Shown above is the ow chart of
our control system where the objective is accomplished by the sensor agging a bad zone and communicating
that to the micro-controller which in turn noties the operator, all the while the motor is propelling the
physical system forward. The communication process is done via transmitter and receiver.
Figure 10: 3D Model of potential design. (Drawn by Sean Barger)
Shown above, in Figure 10, is a 3D representation of our device. Again we do not have the motor, sensor
or power source drawn so we denoted them accordingly with labels. The connecting rods shown in the 3D
image are a lot bigger than what the actual scale will be. They are also staggered on top of each other, the
nal product will actually have interlock connecting rods to conserve space, we had the rods drawn as they
were for posterity's sake.
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15. 6 Senior Seminar I Conclusion
Over the course of this phase of our project we have rened how we will design, construct, and program our
robot, as well as rened it's overall function. We were able to eliminate a few design aws before fabricating
the nal product which will save us time in the long run. Some key decisions that have been made is design
layout, aluminum framing, size of the motor and type of sensor. The decision to use an encoder to tract the
progress of the robot along its journey was also a major one because though it will be dicult to accomplish
it will greatly increase the eectiveness of our robot. We were also able to have a work acquaintance of mine,
Sean Barger, draft up some images for us on AUTO CAD to aid us in fabricating our robot. With these
drawings we were able to further rene our vision of the device. It is likely that our specications may change
once fabrication begins and we are nally able to start testing the device inside the plant. As far as this phase
of the project is concerned we feel that we have set ourselves up greatly to complete our robot by the end of
next quarter.
7 Design Procedure Senior Seminar II
7.1 Week 11- Week 14
From the end of week 10 from Winter quarter to the end of week 2 spring quarter (from now in will be referred
as week 12) a lot has changed in our design. Shown before in Figure 8 was our initial design for our device,
as seen in Figure 11 below it has changed considerably. The new design now has 6 smaller aluminum wheels
with a diameter of 1.125, they were originally sized at 1.625 to t the exact size of the neck guides. The
small wheels will now be spring loaded to keep the shape shown below.
14
16. Ø0.2500
Ø0.8750Ø1.1250
1.1250
1.1250
0.6250 0.3750
0.2500
0.4375
124° TYP
Ø0.5000
2.0000
2.5000
0.5000
2.5000
1.6250
3.7081
1.8540
1.1875
1.1875
0.7500
22°
Ø0.3750
Ø0.4375 Ø0.4375
0.1875
1.6250 1.6250
1'-2.7087
Figure 11: Buggy design dimensions
The new sized wheels and design will allow us to pull the device apart, straighten it and load it into the
neck guide, once we release the device the springs will pull the wheels close together and t snugly into the
neck guide. Not only will this give the device extra stability but it will allow us to load and remove the device
anywhere in the pneumatic conveyor. This is benecial for us because it now gives the Bolthouse technicians
the ability to measure specic parts of the conveyor rather than loading it at the end or the beginning of the
line and waiting for the device to run its course.
15
17. Figure 12: Guide wheels in mock conveyor
SECTION A-A
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Buggy LID 1-1
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BUGGY LID PRELIMONARY
BOTTOM ISOMETERIC VIEW
R.22 TYP
R.25
.25
R.08
R.21
R.23
.87
2.06
.25
R.25
1.63
70
113
.25 TYP
.60
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.02
.02
.02
.25
.59
.13 .60
R.25
.61
.25
.10
.34 TYP
1.63
.02
.02
.25
.55
.02
.52
.54
.21
.34
.47
4.13
2.06
1.03
.22
Figure 13: Buggy lids
16
18. The other added components are the buggy boxes. These boxes will be the housing for the motor, the
sensor and the gear boxes. It will also provide us with a nice at surface on the bottom of the buggy boxes
to mount the power supplies. Each box will have a lid like the ones shown above in Figure 13, the lids will
sit above the neck guide while the boxes sit below it. From the picture it can be seen that their are 4 wholes
beveled out on each corner of the bottom of the lids, the boxes will have similarly sized wholes on the top
that will line up. This wholes will allow from for some sort of axle or bearing to connect the boxes and lids,
this will allow the boxes to travel smoothly down the neck guide.
Figure 14: Buggy gear direction
Shown in the above gure is a rough estimate of how we will compose the gears within the buggies. Since
we are going to drive our device from each buggy we will have to house a gear box in each lid. It can also be
seen in Figure 14 there are two components sticking out from the lid. The bar coming out of the left side
of the lid will connect to the three small wheels, and the component coming out of the right will connect to
the other buggy. The other lid will be a mirrored counterpart to the one shown above. It is likely that in the
weeks to come the specications of these buggy boxes and their lids will change, it is also noted that the way
in which we motorize our device is under advisement as well. It is, however, unlikely that we will change this
general design again from here on out.
17
19. Since we have settled on a more specic design for our buggy we are in contact with the campuses Fab
Lab to construct it. All of our drawings have been drawn in the Auto-CAD and Inventor, this will make it
easy to utilize the 3D Printers at the Fab Lab because their printers use Inventor as well. The 3D Printers
will use PLA plastic to fabricate our boxes, this will enable us to create strong and light boxes for our device.
With construction of our wheels complete, construction of our boxes underway, we now focus our attention
on the design of the circuit.
7.2 Week 15- Week 16
The buggy boxes we have mentioned in weeks past have seemed to have take shape. They are now roughly
4 in length to accommodate room for all of our components yet small enough to still take turns. Both boxes
will be driven by tread tracks and will contain their own gear boxes. Both boxes will be driven by one motor
so while one box will contain the motor the other box will contain the measuring device. Sean Barger, our
draftsmen, drew up the design for out gear boxes shown below.
Figure 15: Gear box mock up
18
20. In the picture above 3 yellow gears can be seen, there are two standard gears on either end and one
worm gear in the center. The worm gear was perfect to use in this instance because we can run two tracks
going in opposite directions at the same time with one motor. There will be two mirrored gear boxes and
the two worm gears will be connected together with metal wire in order to transfer motion from one buggy
to the other. With the mock ups and the general design of out gear boxes done, we were able to fabricate
them. Shown below is the rst fabricated gear box. The box itself has been constructed completely out of
aluminum for several reasons. One being that aluminum is fairly light and stable, and another being that
the aluminum material won't interfere with any of our electrical components that we will be adding soon.
The pulleys mounted to the drive shaft has be securely fastened and will not allow any movement, the idler
pulleys however, are mounted in such away to allow our belt to move back and forth as our device moves.
This design is to limit any potential damage our device could have on the conveyor itself.
Figure 16: Gear box
These gear boxes will be placed in the buggy boxes in order to keep everything packed together. As for
the actual boxes we have nished their design as well and they are currently being created by 3D printers.
Since the boxes are being made out of plastic they will be very light and fairly sturdy, they are merely being
used to make everything as compact as possible and to add a bit of style. Shown below is a mock up of how
the boxes will be constructed and how the gear boxes will t into it.
19
21. Boxes.PDF
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Sean 5/4/2016
DWG NO
Gear Box - Assembly1
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Figure 17: Gear box enclosure
From the image above you can see the gear box enclosed in three dierent colored pieces. The Blue piece
is the top of the buggy box, this will be riding on top of the neck guide. The Green piece is a simple box that
will be resting unfastened, enclosing the gear box. The Red Piece is the bottom plate and will mounting the
gear box. There will be bolts that will travel from the top plate through the gear box and into the bottom
plate, this will ensure the gear box is mounted securely. By looking at the bottom left image in Figure 17
you can see a side view of out buggy. The gap between the blue top piece and the green box there will be a
belt. This belt is what will be driving our device along the neck guide. It is noted that both buggies will be
identical to this design.
One signicant change in our project that we have made these past two weeks is the fact that we will no
longer be using a sensor. This unfortunate set back is do to the fact that there is simply not any sensor on the
market today that ts our needs. First and foremost all of the sensors we were looking at were in the $500.00
range, which would not have been a problem except for the fact that they were not going to be as ecient.
20
22. We require a sensor that is capable of measuring to extreme precision and is small enough to t within our
device, the latter proved to be the deciding factor in which we scrapped the idea of a sensor. The solution
we came up to x this snag is in place of a sensor we will now use a potentiometer. This idea will actually
improve in not only the precision of the measurement but how often we will be able to measure. The benets
of no longer using the sensor is that we can now measure every inch of the track whereas with a sensor, due
to the time delay, we would have only been able to measure every six inches. A draw back however, is that
the circuit we design as to be much more complicated.
The way in which we will utilize the potentiometer is as follows, as our device travels along the conveyor
the potentiometer will vary in length as the neck guide varies in width. The change in distance across the
neck guide will directly change the resistance across the potentiometer. The change in resistance will in turn
vary the output voltage as well as the output voltage frequency. The circuit that we are designing will record
the variations of output frequency from a range of 3kHZ-8kHZ. Then using 7-segment displays the circuit will
display the variations in frequency as 1000th decimal places. Since we know that a brand new neck guide is
approximately 1.43 if we were to measure it we should see an output of 3kHz. The frequency is eectively
acting as the thousandth decimal place were the prex to the display will always be 1.4.
Unfortunately though we have all of the components for a running prototype the actual belts that will
be used to drive the device are 4 weeks out from delivery. This will mean the the completion of our project
will be cutting close. Since we are unable to see if we can actually get our device to move down the track we
will be turning our attention to the circuit and seeing if we can get an accurate measurement. It is our hope
that by end of this quarter that our project will be complete and once we get the belts in we will be able to
use our device on the actual conveyor. This regretfully leaves us with virtually no time to trouble shoot the
mechanics of the device, we just have to hope it will travel down the track.
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23. 7.3 Week 17- Week 18
For the past two weeks we have turned our attention heavily on that of the circuit. Due to the set back of
having to scrap the idea of using a digital sensor the circuit we have to design now is far more complicated.
The logic alone on the circuit is very complex and in order to get the timing right we will have to make use
of several logic gates. Due to the fact that the circuit is much more complicated than initially theorized it
will likely be very big. For that reason as of now we are constructing the circuit on a bread board so that we
can demonstrate the theory behind our device. Since the circuit is going to be larger than we had originally
thought, it will not be attached to our device just yet.
Our main goal now is to be able to demonstrate the circuit reading and displaying values from a neck
guide without traveling with the device. The demonstrates of the device traveling down the neck guide and
the circuit taking measurements will be done separately. That, unfortunately is the base case scenario for our
project through the confounds of the quarter. Moving forward beyond the quarter we will be programming
our circuit into a PLC chip, this will greatly reduce the size and complexity of the circuit and we will be able
to mount that to our device. Unfortunately due to the ever increasing deadline of the quarter we will not be
able to achieve this until after the quarter.
The theory behind our circuit is as follows, the circuit is composed of two main parts. One part of the
circuit determines the size of the neck guide while the other keeps track of how far the device has traveled.
As our device travels along the pneumatic conveyor the potentiometer will be outputting a frequency which
will be sent to the circuit. The circuit will contain a frequency to voltage converter. Once the frequency is
converter the output is sent to a 555 monostable multivibrator IC chip which then takes the data and puts it
into a readable form that can be displayed. Shown below is what we have built for the frequency to voltage
circuit. This is the important portion of the circuit because it will be getting the bulk of the data for the
technicians. Shown below in Figure 18 is what we have now for the frequency to voltage converter.
22
24. Figure 18: Frequency to Voltage converter circuit
The other part of the circuit will be utilizing an encoder attached to the drive shaft of the motor. As
the shaft spins the encoder sends pulses to our circuit. Since the encoder operates at 300hz we utilized two
4017 decade counters that dived the input by 24 to slows down the output to make it readable. We get the
24 count by using a 4066 quad bilateral switch that takes in the two outputs from the decade counters. The
rst decade counter sends a pulse every 4 seconds to a switch while the other sends a pulse every 2 seconds
to a dierent switch. It is not until each switch receives a high logic input at the same time does the 4066
quad bilateral switch resets and increments by 1. The switches output then gets sent to a 555 monostable
multivibrator , which will sample and hold the encoder value. Each incremental value that gets sent to the
555 monostable multivibrator timer is representative of 1 so by the time our device has nished traveling
down the conveyor we will be able to read the nal value of the distance traveled. As of right now we are
sending the data to a bank of 7 segment displays so that we can see the data in real time. Once the quarter
is over we will be swapping out the displays for a memory chip so that the data can be saved and analyzed
by technicians. Shown below is what we have now for the encoder circuit.
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25. Figure 19: Encoder Circuit
7.4 Week 19- Week 20
With the quarter coming to a close the device has nally taken what we hope will be its nal shape. Not
much in the device has changed since Week 16 but there has been minute changes in both the gear box as well
as its enclosure. These changes have come about in trouble shooting and testing the device on a pneumatic
conveyor. The following gures are the nalized design specs that we will be turning in at the nal day of
class.
24
26. MIDDLE
2.16
2.061.64
5.08
5.50
.21
R.33
R.21
1.51
Figure 20: Middle Enclosure Plate
Shown above in Figure 20 is the middle enclosure plate. This plate is designed to rest on top of the base
plate and enclose the majority of the base plate. A hole can be seen on the right hand side of the plate. Since
our device is going to be composed of two gear boxes driven by one motor we needed away to transfer the
motion from one gear box to the other. We decided to do this by utilizing a metal cable which will attach
one worm gear to the other. The hole on the side of the middle plate is all a sizable area for the cable to move.
25
27. BOTTOM
.741.131.562.06
5.50
.65 3.89.47 .50
.45
.20
1.00
5.00
Figure 21: Base Enclosure Plate
The Figure 21 you can see the base plate for the enclosure. This is where the gear box will be mounted
to on our nal product. Each gear box will have an identical base plate to ensure that the gear box is fastened
securely. The benets of these base plates is to give our device a box like shape which will allow us space
underneath to secure the battery packs. Finding the space to secure the battery backs took a bit of time,
due to the fact that we have an encoder, a motor and a circuit to power we will have to strap quite a bit of
weight to our device. The box like surface of the bottom of the base plate not only ensures a stable mount
but also allows us to distribute the weight and not cause any damage to the conveyor.
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28. FRONT LID
1.63 1.185.50
8.30
.23
.45
.23
.45
R.38
R.58
Figure 22: Front Buggy Cart Lid
Shown above is the lid for the front buggy. The lid will serve two purposes:
1) Allows us to secure the gear box
2) Allows us to attach the guide wheels
The lid will secure the gear by with the set screws of the gear box and base plate. On the left side of the
lid you can see 4 holes with identical diameters. Those wholes will allow us to drive screws from the top of
the lid to through the gear box and down into the base plate. In between the lid and the top plate of the
gear box these 4 bolts will be housing the pulleys for the belt. The two holes on the far right will serve the
same purpose. The oval shaped holes however will serve a dierent purpose, instead of having bolts that go
through to the base plate it will instead have bolts that are just fastened to the top of the gear box. The
27
29. bolts will have also have pulleys attached to them in that space between the lid and the gear box. These
4 oval shaped wholes have been elongated to allow the belt driving the device to uctuate in length as the
device travels. This uctuation will be where we take our measurement of the conveyor.
BACK LID
5.50
8.30
1.63 1.18
R.38
R.58
.23
.45
.23
.45
Figure 23: Back Buggy Cart Lid
The second purpose the lids serve is attaching the guide wheels. The guide wheels can be seen back in
Figure 12 attached in a mock conveyor. These guide wheels do exactly as what they are named, they will
act as a guide to the device as it travels down the line. Not only do the wheels guide the device but because
they are spring loaded to take to the size of the conveyor they actually help distribute some of the weight
of the device. The only dierence between the front and back lid is the connecting bracket on either end, as
28
30. they are designed to connect into one another.
Gear Box Assembly
1.32
1.07.363.59
5.00
Figure 24: Gear Box Assembly
Now we can see the actual design of the gear boxes. There will be two identical gear boxes mirrored to
one another married by a metal cable which will be fastened to the worm gear. You can see in Figure 24
the 4 extra long bolts on the ends of the gear box which will be fastened to the top and bottom plates. From
the top view of the gear box you can also see the 2 pulleys on the left hand side are closer to each other than
the other 4. These 2 pulleys will be fastened solid so that they can not move like the other 4. The 2 fastened
pulleys will be the exact size of a new pneumatic conveyor so that no matter what the belt will be able to
make contact with the guide rails.
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31. .62
.16
1.16
3.59
1.41
.39
.24
Gear
RollerFastener
SeparationSheath
M
ulti-LevelFastener
RollerFastener
RollerSprocket
3.46
.19
.55
Middle Plate
Bottom Plate
.39
.34
GEARBOX
5.00
.60
R.08
.35
.16
.22
1.56
.59 1.65 1.65 .65 .22.25
.16.12
.16
.65 3.89 .25.22
.41
.22 .25
.13
1.65
.59 1.65
R1.57
Figure 25: Gear Box Specications
By looking at Figure 25 you can see all the necessary information to be able to construct from start to
nish one of our gear boxes. Included is the middle plate, which is the top of the gear box, and the bottom
plate which is the bottom of the gear box. As said earlier, the gear boxes are made out of aluminum to keep
the weight of the device fairly minimal but also give us the support to fasten all the necessary components.
Also included is the dimensions for the roller sprockets, or pulleys, as well as the nuts and bolts we used to
construct the gear box.
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32. BACK
ASSEMBLY
.27
.27
.55
Figure 26: Gear Box and Enclosure
Finally we get to Figure 26 which shows you how it will all by put together. Now you can clearly see
the bolts being driven down from the top plate through the gear box down into the bottom plate. The space
between the top of the gear box to the top plate can be seen to by .55 which will be the space reserved for
our 1/4 belts that will drive our device. It should be noted that the middle enclosure is not included in
Figure 26 but can be seen in Figure 17. The middle piece is simply slid on top of the gear box once the box
is fastened securely to the bottom plate. This is essentially all the necessary information needed to construct
the gear box and it's enclosure in its entirety.
The mechanical portion of the project as been done for about a month now, give or take a few adjust-
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33. ments here and there, so what we have been spending the majority of our time on is the circuity required
for the project. Due to our set back of not being able to use a sensor we have fallen behind in this portion
of our project. As explained earlier we will not have a fully function device by the deadline, instead what
we have is a demonstrable proof of concept. Our device can essentially be divided up into three parts, 1)
the physical device itself, 2) the ability to track how far the device has traveled down the conveyor, and 3)
the ability to measure the gap of the guide rail. Shown below is what we were able to complete as far as part 2).
Figure 27: Encoder Circuit
This is the nalized Encoder Circuit that was shown back in Figure 20, it has been expanded to include the
555 monostable multivibrater timer which can be seen on the top circuit board. As we explained earlier the in-
put pulses from the encoder gets divided by 24 by the two decade counters and the quad bilateral switch. The
output from the switch gets sent to the 555 timer which then increments a bank of 7-segment displays. Every
value that gets sent to the bank of displays is one inch. One main issue we occurred in designing this circuit
is trying to bias the encoder to allow it to go from high to low logic to trigger the decade counters. Trying to
bias the encoder involved nding the correct resistance to place at the rst decade counters clock input. To
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34. do this we placed a 5.6k resistor on the input from the encoder and two 1k resistors in series to ground from
the encoder. Finding these correct resistance values required a lot of diligence, which included starting from
a 100k resistor and testing it all the way down until we reached our range. Needless to say this took quite a
while but now this encoder circuit eectively keeps track of how far the device has traveled. This is important
because as this circuit denotes how far the device has traveled the other circuit measures the neck guide.
Now the technician can see roughly were on the conveyor the values were recorded so if a large value gets
outputted the technician can nd it. Shown below is how we plan on demonstrating this portion of our project.
Figure 28: Encoder Circuit Demonstration
Figure 28 shows how we are demonstrating our encoder circuit, the bank of 7-Segment displays will
display both the encoder circuit and the frequency circuit. The far left two displays will be used primarily
for the encoder circuit while the three right displays will be used for the frequency circuit. The motor with
the encoder cannot be seen in the image but it is powered by a 12V power source. The bank of displays gets
6V and the circuit itself gets 6V. It can be seen on the far right of the large circuit board two knobs. The
bottom knob is a switch that controls the display. This switch allows us to pause the display so we can see
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35. that it is taking values at the same time. The top knob is the potentiometer, we can see the rate in which the
3 7-segment displays take values change as we vary the resistance across the potentiometer After the quarter
is over we will be swapping out the bank of 7 segment displays for a memory chip to store the data, this will
make analyzing the data much easier for the technician as well as free up some space. Also as you can see
the circuit itself takes up quite a bit of space, this will be swapped out with a PLC chip. We are going to use
a PLC because of the high logic and relative ease of programming. In addition to that Bolthouse uses a lot
of PLC devices through out the plant so this will be very compatible interface for the technicians.
The third and nal part that we need to be able to demonstrate the proof of concept of is the poten-
tiometer. The potentiometer will actually measuring the neck guide, as the it varies in resistance our circuit
will take those inputs and convert it into readable data. This involved us tweaking the potentiometer so that
when the potentiometer was set at 30k Ohm's the neck guide would be set at 1.43. So now, it follows that
if the neck is 1.48 the potentiometer will be at 80k. Previously we stated that if the output resistance was
to be 3k Ohm's is would yield a neck guide distance of 1.43 but due to the change in capacitance we had to
use larger resistance. Whats really going on in this circuit is a frequency to voltage converter, the astable 555
timer acts like sort of a teeter totter with the capacitor. The astable 555 timer is constantly switching the
capacitor from high to low, charging and discharging it, as the potentiometer's resistance decreases the rate
or frequency the capacitor chargers and discharges increases. So now we can take that frequency and we can
apply it to the distance of the neck guide. The circuit is already designed and put together what we need to
prove is that we can vary the resistance of the potentiometer as it is the key component of the circuit. Shown
below is how we plan on demonstrating this portion of our project.
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36. Figure 29: Potentiometer Demonstration
In Figure 29 you can see a tiny piece of track, a potentiometer,a gauge, and a dial to adjust the track.
When the gauge is set to 30mm we set the resistance of the potentiometer to 30k Ohm's. Now if we twist the
dial we can adjust the gap width of the track, we will then see that as the track size changes the resistance of
the potentiometer changes too. In our actual device we will see that as the track size increase the resistance
will increase but for demonstration purposes we inverted this for simplicity. The values that will be outputted
from our potentiometer will be inputted into an astable 555 timer. The monostable 555 timer on the encoder
circuit triggers the astable 555 timer on the potentiometer circuit. This insures that every time the monostable
555 timer takes a value from the encoder the astable 555 timer takes a value from the potentiometer. This
will allow us to make sure the two values are being taken from the same part of the conveyor at a 10th of a
second each time.
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37. 8 Senior Seminar II Conclusion
As the quarter comes to an end we reect upon what were able to accomplish on our project. What we were
able to nish is more than enough to have proof of concept for our device and project. Of course there is
much more to complete and ne tune and the nal product will likely look much dierent, these are the key
components of our device and its functionality. What we have now is a solid base for us to continue on and
with everything we have accomplished thus far is encouraging us to continue further. We realized that we
have to be able to come up with clever solutions when faced with big set backs, we clearly had to play catch
up at the end when we were not able to make use of a sensor. We also had to deal with set backs by having
to wait a month for key parts and not being able to 3D print parts for our enclosures. Even though we faced
many set backs we still managed to push on out to our deadline and come up with a demonstrable device.
A more important lesson we learned was when to utilize other professionals and resources when trying to
accomplish a project. If it wasn't for Sean Barger, our draftsmen, and Rick Horung, our engineering contact
at Bolthouse we wouldn't have been able to complete as much as we did. Having these two help guide us
through this process was just the little added push we needed to bring a demonstrable device to the table.
One thing we will take away from the project is the experience with working as a team and utilizing the
strengths of our fellow teammates.
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