Total Recall Engineering Notebook

Total Recall Engineering
War Eagle Best, 2010
Stanhope Elmore High School
Team # 23
4300 Main St.
Millbrook, AL 36054
(334) 285-9989
Written by:
Danny Pacheco-West
Trey Harris
Kevin Alvarez
Destiny Barbaree
Hope Kicklighter
Hannah Ebeling
Contact Information:
Jennifer Cox
[email protected]
Total Recall Engineering Notebook
Stanhope Elmore High School
Team # 23
Table of Contents
Section
Page Number
1. Research Paper: Total Recall; The Manufacturing Process
3-4
2. The Engineering Process
I. Introduction to the Metal Mustangs
5-7
II. Problem Identification and Documentation
7-8
III. Project Goals
8-9
IV. Brainstorming
9-10
V. Component Design, Evaluation and Testing
10-19
VI. Analysis if Proposals and Materials
20
VII. Prototype Construction and Assessment
21-26
VIII. Test and Optimize
27-31
IX. Final Product Construction
31-32
3. Attachments
33-46
4. BEST Team Demographics form
48
Total Text 30 Pages, Appendix 13
2
1. The Manufacturing Process
Manufacturing is the use of machines, tools and labor to produce goods for sale or use.
The term may refer to a range of human activity, from handicraft to high tech, but is most
commonly applied to industrial production, in which raw materials are transformed into
finished goods on a large scale. Such finished goods may be used for manufacturing
other, more complex products, such as aircraft, household appliances or automobiles, or
sold to wholesalers, who in turn sell them to retailers, who then sell them to end users –
the “consumers”. Manufacturing takes turns under all types of economic systems. In a
free market economy, manufacturing is usually directed toward to the mass production of
products for sale to consumers at a profit. In a collectivist economy, manufacturing is
more frequently directed by the state to supply a centrally planned economy. In free
market economies, manufacturing occurs under some degree of government regulation.
Mass production is central to the manufacturing process. Mass production is the usage of
assembly lines to carry half finished products to workers who complete repetitive and
simple tasks to build the products. Popularized in America by Henry Ford, mass
production allows our modern economy and markets based on cheap and readily
available goods. As technology improves, mass production changes. What used to take a
few hundred workers all day, such as making a car, now can be completed by robotic
factories manned by a handful of people.
Manufacturing begins with the acquisition of raw materials. These may be the
ingredients for foodstuffs, or metal for cars. These materials are then refined into their
simplest usable forms. This is then shipped to factories which make these materials into
parts; these components are pieces of the finished product. These are then put on an
3
assembly line and put together as the finished product. Afterwards they are packaged
and shipped using similar methods. Complete control of the process from raw materials
to shipping finished products is called vertical integration. This is a rare method,
however, since many would rather focus on the core product and buy the materials from
elsewhere rather than invest in mining and foresting to obtain those materials.
Modern industry is turning to the far more reliable and cost-effective automated
manufacturing. This usage of machines such as robotic arms to assemble products has
created a drop in demand of factory labor, but increased demand for engineers and
programmers to build and design better equipment for manufacturing.
The main focus of this game however is quality control. Quality control is the
process of examining products produced and assuring that they are all of usable quality.
Until recently this was all human labor however modern technology has created machines
that can perform quality control operations such as determining magnetic properties.
much like our own robot.
This modern age of manufacturing has created a competitive job market for
engineering management and technical specialists, while flooding the markets with
highly demanded cheap goes that are starting to be produced faster than demand or
resources can keep up with. The great worry of the future is if a field that is so focused
on efficiency will become so efficient that it puts itself our of business.
4
II. Introduction
The Stanhope Elmore Metal Mustang Robotics Company has spent the last twelve
months eagerly awaiting the next robotics challenge/project to accomplish. Our
company has ten years of experience, is strong and well organized. We are equally
concerned about the quality of our product and the safety of our employees in the design
and manufacturing process. We have made the combination of a technologically capable
and environmentally safe working environment a priority for our company
Our annual safety seminar, held September 13, 2010, was conducted by our
advisor and safety consultant, P.R. McGiver. To ensure our employees were trained on
all the tools that would be possibly used to build the robot, the safety certification process
consisted of demonstrations of the proper use of the power tools, techniques to use the
tools for the manufacturing process, reminders (since our company employees many very
young and inexperienced personnel as part of our corporate philosophy) to not use certain
saws without proper experienced supervision, and reminders to always wear safety
glasses to protect the eyes.
Safety Training
5
Our past involvement in the development of different robots to solve different
problems has demonstrated to us the importance of using an engineering process as the
structure for our efforts. Though the process may vary from company to company, we
feel that our take allows our engineers the freedom to brainstorm and be creative- either
individually or in groups- while also ensuring an assessment of effectiveness and decision
making capability. Continuous reference back to the agreed upon project goals keeps
everyone on track. The process has also been flexible enough to integrate the increased
demand for software using C Programming in recent years to increase the effectiveness
of the robot and allow for additional technology such as IR sensors, magnetic switches,
and code readers.
Total Recall:
As we had hoped, we were notified of an information seminar (Kickoff Day)
scheduled for September 17, 2010. Our team attended the seminar and learned about our
new challenge/project for 2010: Total Recall.
Following the seminar and all the technical meetings, training sessions of
software and hardware, pickup and inspection of
construction materials we immediately began by
closely studying the project specifications (rules).
Additionally, at this time our support team began
construction of a mock playing field to give the
Mock up of
Playing Field
engineers a real world working environment. The playing
field in the robotics trailer is pictured below.
6
Two things immediately became apparent: to succeed in this project we would
need accurate and innovative software to drive the robot and a creative, robust, and
simple to employ hardware design. Our successful ability to integrate the software and
hardware would prove to be the key to our success.
II. Problem Identification and Documentation
The team assessed in detail the project specifications. The challenge was to build
a robot that will collect gizmos and gadgets, transport them to the sorting facility and
return defective gizmos and gadgets to the factory while ensuring that the quality of the
processed and shipped materials had the highest Sigma possible. Our robot would also
have to pack the gizmos and gadgets for shipping. During each round of the
demonstration process, the team would face a different scenario in which they must
determine which gizmos and gadgets will be defective. The gizmos must be sorted based
on magnetism and the gadgets by color.
The robot can dock at the Data Port to discover which products are defective
during the round or the spotter can wait until 1:30 minutes to find out which are
defective. Gadgets are managed by the robot and the assistant production engineer
(spotter) and packaged in shipping tubes. The robot will then have to pack the gizmos for
shipping by turning a cone upside down, placing the gizmos inside the cone and placing a
lid (Frisbee) on top of the cone.
The competition rules require that the robot must fit into a 24 by 24 inch box and
the robot can only weigh 24 lbs. Only the materials listed and provided in the kit can be
used to build the robot and no more. The robot needs to be able to perform the tasks
7
listed by the game rules in a three minute round. The game this year requires that you do
a handful of different tasks that involve different mechanics for example you need to pick
up a variety items and rotate a few. This is different from other years where you had to
pick up similar items and move them all in the same way. The simplest of tasks this year
you have to receive golf balls from a pipe. You must pick up cones and rotate them into
slots. You also have to scan eggs for magnetism then pick them up and put them in the
cones. Finally we have to seal the cones with disks. There are certain items each round
that have been recalled they will negatively affect your score if left in the cones or on the
ground. The same applies to the golf balls you send to the spotter. The game rules
provided specs for a data port that we can link with the field with to receive the
information of what as been recalled. Scoring combines points for each item and a sigma
six ratio for a multiplier of the score.
Given the nature of this project, we knew that ultimately, we needed to use the
engineering process to build our robot to remain competitive in today‟s market. This
process involves brainstorming, designing, drafting, blue printing, building, and testing.
III. Project Goals
The entire team met over two to three days using the rules, seminar information,
assessment of the playing field and limitations provided in the specifications to determine
the overall goals of the project in two areas: software and hardware. The goals are as
outlined below:
8
a. Software: use the Easy C programming system to provide for
1. steering control using a two motor tank steering system and
extension/retraction of an arm mechanism
2.
support the operation of an attachment mechanism that rotates, uses
servos to pick up gizmos, cones and Frisbees.
3. allow reading of the Data Port to determine defective products
4. modify servo operation to allow full 160 degree rotation with one
control input.
5. support use of reed switches to determine magnetic properties of
gizmos.
b. Hardware: using materials provided construct equipment and substructures
that will:
1. move and provide directional control of the robot
2. lift and manipulate an attachment mechanism that rotates through 360
degrees
3. pick up multiple gizmos
4. load and transport gadgets in mass quantities without operator input
5. move and rotate gizmo packing containers (cones)
6. package gizmos (place Frisbee on top of cone)
IV. Brainstorming
We had our goals and began brainstorming ideas for our construction. There are
three sections we divide the robot into: the base, the arm, and the claw. We developed
the timeline below knowing we had six short weeks to accomplish the task. For
9
documentation purposes we began a journal to keep up with our progress and to make
sure we were meeting our deadlines. For sample journal entries, see Appendix 1.
Week 0
Week One
Week Two
Week
Week Four
Week Five
Week Six
Three
Safety
Study the
Prototype
Arm
Driver initial
Final
Driver
Training
rules
Construction
Construction
practice,
modifications
practice
Brainstorming
Base
and Claw
modifications
and painting
and
Playing Field
Construction
modification
based on
strategy
Construction
Claw
feedback
sessions
Construction
We started with pen and paper sketches and worked off of the white board. Each design
was discussed and the pros and cons of each sketch were discussed. Finally, we decided
on a base design, articulating arm, small wheels for speed and several competing claw
designs. We split into several teams to complete over the claw designs.
V. Component Design, Evaluation and Testing
Base: The base is the simplest part. We decided to use arcade steering for our
base so we simply agreed on a U shaped base. Two of our new employees quickly got to
work to design the first prototype once the design was set. Josh designed the base in
CAD as seen below.
10
We tested various diameter wheels knowing that big wheels equals low torque and high
speed and small wheels maximize torque and decrease speed. The second thing a smaller
wheel does is increase controllability since the robot responds slower to inputs. For this
game, finite control is import as is torque- we accepted the trade off in speed. The
wheels are wrapped with friction tape. Holes were cut out of the wheels to reduce the
mass of the robot. Small holes were drilled into the edge of the wheel and laced with
nylon rope to give the wheels more friction on the floor. The base and wheels are
pictured below.
Wheels with Friction
Tape and String for
Traction
Arms: The arm is a little more complicated. As part of the process we assessed
a straight arm, an “L” shaped arm that rotated “over the top” and an articulate arm. After
construction and testing of all three we decided on an articulated arm to keep the claw
level throughout its movement and stable.
11
Articulated
Arm Attached
to Gearbox
This was important because we needed to pickup gizmos from flat and level on
the floor, Frisbees from slightly angled on the floor, cones from flat on the floor and
move all of these items up 22 inches to the packing area while keeping them parallel with
the horizon to accelerate the packing process.
To move the arm up and down we built a handmade worm gear to raise the arm
slowly and controlled to make it more stable.
Gearbox and
Drive Motor. Note
Worm Gear at
Bottom
Rotational Device: We realized in our brainstorming that to invert the cones for
placement we either had to take them “over the top of the robot” or create a rotational
mechanism. Over the top was tested and rejected due to compliance issues and a
rotational mechanism developed.
12
A small motor was mounted on a flat plate of polypropylene faced with aluminum
sheeting for support and stiffness this was then attached to the end of the arm. Two
mechanical stops were installed to stop rotation at 180 degrees right and left. It was a
simple matter then to build a mount to attach any kind of claw mechanism designed. The
system works well.
Rotational Device
Mounting Bracket
Claws: (All types of attachment/grasping mechanisms)
The claw is the true challenge of the game. We knew it had to be able to grasp
three totally different shapes and rotate one of them (the cones). In our brainstorming
sessions we searched for a design that would do all three but realized in might require
individual components for individual tasks. We divided into teams and individuals to
brainstorm claw ideas. Ideas were sketched on the white board in our workshop or drawn
on paper. Several of our engineers each had a claw designs worth assessing.
a. Daniels Claw
I wanted something simple that could achieve any of the game goals. It needed to
be a design that probably wouldn‟t be attention getting but would be a reliable fallback if
nothing else worked. I knew it needed to rotate at least one hundred and eighty degrees.
13
It was simply two strips of metal with a half inch hump bent into the metal to provide
grip on eggs and golf balls. This item could pick up any of the game items.
Another major consideration was rather or not we wanted a rotate option on the
claw for the cones or should we simply flip the arm over the back of the robot with the
cone to drop it. We decided to rotate the arm, however, the weight of the claw could
potentially flip the robot over. The base of the robot would have to be stable to prevent
this from happening.
I built the claw out of two 1inch by 12inch strips of metal. It had to 90 degree
bends in it to mount it on the servo while the other strip bent to mount a motor for the
rotation. Then I took the flat parts and bent them over a 1 inch rod. These humps were
shaped just right to grip eggs The servo would be mounted on a piece of metal bolted on
to the motor we would use to rotate the claw .
Daniels Claw (Left) with Cone
Modification (Right)
b. Kevins Claw
Kevin proposed a claw that would grab multiple eggs underneath the claw by
opening and closing the grabbers, rotate the claw and deliver the eggs to the packing area.
On the first day of brainstorming I knew I wanted to do something different. I wanted the
14
claw to be able to do everything that we needed to do. Of course I soon realized it would
be harder I thought.
The first 30 minutes or so I just sat and thought about what could be done.
Suddenly it hit me and I began drawing on our dry erase board. It would be two
stationary pieces of bent PVC facing outward in the middle with two moving pieces of
aluminum on tracks facing inward. The two servos would be mounted in between the
PVC and I would use piano wire attached to the aluminum pieces to move them. The
PVC pieces would be elevated away from the base as to give room for the piano wire.
First Sketch of Kevin’s Claw
Idea
Soon, though, I realized that the servos only move so far. If the piano wire starts
on one end of the servo, 180 degrees later it only moved the piano wire about one inch. I
knew this would not suffice for the actual amount of movement I would need to open the
arms wide enough to grab eggs. Thus, I moved on to revising my design.
From previous years, I knew that having the arms pivot on a hinge and having the
piano wire attach close to the pivot point I could significantly increase how far they
15
would travel. With this in mind, I decided that I would use “L” brackets that attached to
the base to hold my hinges, and the arms would be mounted directly to the hinges. With
my design looking very solid I started on building my claw.
The first pieces I decided to build were the stationary PVC pieces. I accomplished
this by taking 4 inch long and 1.5 inch wide pipe and cutting one side down the middle
long ways. Then, using a vice the hold the pipe I heated up the PVC with a propane torch
to make it malleable. Once I got it mostly flat I then heated it up again and clamped it in
between to pieces of plywood to make it perfectly flat. Once I accomplished this I heated
up the PVC again and bent it to match the curve of the egg, so the egg would fit snug
when grabbed. When this was done I bent the peak of the curve on both sides in with a
pair of pliers to keep the egg from falling out. With my PVC pieces done I wanted to
check my clearance for the servos. At first, I used two servos, but as we continued with
the robot we needed one of them for our Frisbee grabber, so I redesigned the claw to
work with only one servo. This part will be explained in our Test and Optimize section. I
cut out a small section of the PVC closest to the base to allow the servos to have room to
move.
Servos Mounted
(Prior to Arm
Attachment)
16
Since I was finished with the inside pieces I had to make the outside pieces. This
was a relatively easy process. I took a strip of aluminum and made somewhat of a
question mark design with it, the scoop part being the part that would hold the egg to the
PVC piece. After I got the shape I wanted I mounted half the hinge to the flat part of the
“question mark” and the other half of the hinge to the “L” bracket. On the back of where
my arms attached to the hinge I put a strip of aluminum parallel with the base. Here, I
drilled a small hole and ran my piano wire from the hole to the servo. With the wire
attaching close to the pivot point of the hinge I could improve how far open my arms
opened. To attach my claw to the motor, I used a small block of aluminum in which I
drilled two holes on one end to mount to the base of my claw. On the other side I put a
hole straight down and one hole straight into the block. I tapped the hole facing down to
allow the use of a bolt to clamp down on the motor‟s axle. After this I had finished my
claw prototype and we were ready to test it.
Final Gizmo Grabber
with all Components
Attached
17
c. Hope and Destiny’s GizmoCatcher: “Making the Metal Marshall”
Hope and Destiny proposed a hook claw with a platform to pick up the eggs by
pushing them together to stick the magnetic eggs together. The claw would lift and
transport the eggs as well as lift the Frisbees.
When we got to robotics on Saturday, we needed to design a device that could
pick up a Frisbee, lift it up and put it on a cone. When we came up with our first design it
was just a piece of wood and what looked like two bent fingers. The steps in the process
were
1. We cut out our base which was just a curved piece of wood.
2. We had to the figure out how to mount the servo onto the wood, but we ended up
cutting the wood to short so we had to retry.
3. We had to cut out a small piece of wood on our base to set the servo.
4. We traced Hopes index and middle finger onto a piece of lexan glass and left
about an inch so we could mount the arm on the servo.
5. We used the torch to heat up the fingers of the lexan glass and bend them into
what looks like “bent fingers.”
6. We came to see that the arm would not mount onto the servo correctly so we
again took the torch to heat up the one inch left over piece and bent it 90 degrees
so that it would mount onto the servo.
7. We pieced it all together and tried it out.
18
Destiny Testing Claw on Gizmos
Claw in Relation to Grabbing
Frisbee
Transportation of Gadgets: The team immediately rejected the idea of moving
gadgets individually by “picking them up” and quickly settled on the idea of constructing
a container of sufficient size to move and release up to 60 gadgets at the same time.
Basic construction was begun using cardboard to assess the effectiveness of the proposal
and not waste materials.
Constructing Gadget Box from Cardboard
(left) and with Gadgets on Robot (right)
19
VI. Analysis of Proposals and Materials
There were no other ideas for the golf balls other than picking them up
individually which was highly inefficient. Finally the collection bin was discussed with
a flap on the back to dump the golf balls. This was demonstrated to be very effective.
Software solutions were proving to be effective and the rotational device was perfect.
However, there were claw issues:
a. Kevin‟s claw could only pickup eggs while Destiny and Hope‟s claw could
only pick up the Frisbees and magnetic eggs.
b. Josh‟s first claw only got eggs and was unable to control which ones it got.
c. Danny's claw was would only be able to pick up one to two items at a time.
VII. Prototype Construction and Assessment
a. “Building the Base” When we started to build the robot, first it would need a
base. We cut pvc pipe to provide framework, while I used ply wood to provide a
platform and general structure for the robot. We had to start over a couple of times to get
the measurements right, but we finally figured it out. It took a lot of hard work, but it
works and looks great!
Destiny and Hope constructed a base for the robot as pictured below.
We built a cardboard box as a prototype to collect the golf balls with a slight ramp
and upwards opening hatch allowing the base to the box to fit on the base and not
20
interfere with the arm on the robot. The robot will park below the pipe to collect the golf
balls as they fall. Patrick suggested building a flap on the back with a servo to open and
close the box. The box had to be mounted at least three and one half inches above the
playing floor so the gadgets could drop into the collection and sorting container. Patrick
is pictured below fitting the servo to the box.
.
Patrick Attaching Servo to
Gadget Box
b. Software Solutions: Dustan’s Programming
As previously noted the engineers wanted software to do the following: steering
control using a two motor tank steering system and extension/retraction of an arm
mechanism, support the operation of an attachment mechanism that rotates, uses servos
to pick up gizmos, cones and Frisbees, allow reading of the Data Port to determine
defective products, modify servo operation to allow full 160 degree rotation with one
control input and support use of reed switches to determine magnetic properties of
gizmos.
21
When going over the basic concept o the game, I noticed the unique concept of
the data port. I realized I would have to create a way for the robot to sense the electrical
current that is provided by the data port. I decided to command a servo to move
according to the signals the data sensor would receive. I used the variables P0, P1, and P2
to represent the metal „fingers‟ of the sensor. Then, after discovering the range of the
servo via setting the servo to specific points, I created the equation for moving the servo
according to the readings from the port. We were ecstatic when it finally detected the
signals just as we wanted it to.
The next challenge was being able to detect the magnetic gizmos. At first, we
considered just attaching a magnet to the robot somewhere, but then became afraid it
would possibly mess with some readings. So I decided to create a way to make our back
door open when the robot detects a magnet via reed switch. I replaced the original
command for the door with a similar equation as the data port sensor. All I had to do was
set the servo to a certain position whenever the reed switch closes and sends a signal. It
worked beautifully.
Finally, using the capabilities of the Easy C Program I developed the software that
controlled all of the motors, servos and sensors of this robot. The software is pictured in
Appendix 2.
c. Hannah’s Data Port and Display Dial
After Dustan had the program working, we needed something to get the
information on the defective products and to show that information to the driver and
spotters. First I made the sensor fingers. An engineer cut a piece of wood and attached
the metal fingers to it, so that we could read the information. But we always had to press
22
each metal finger on the sensor. To make this easier, I made some spiral springs. I took
paperclips and wrapped them around a screw. Then, I attached them under the metal
fingers between two nuts. Now you don‟t have to press each metal finger itself.
To check if everything is working, we first put a straightened paperclip on the servo that
pointed out the different degrees. I marked each direction on a piece of wood and noted
each angle with a protractor.
For the final robot I then took a piece of polypropylene, drew half a circle and cut
it with the band saw to make the Data Port Display Dial. I also cut out a piece out of the
bottom to mount the servo. I drilled two holes next to the servo piece and screwed the
servo on it. Than I cut a long, thin piece of metal, to use as the pointer and attached it on
the servo.
Then I tried all possible combinations of the different switch combinations (001,
010 etc.) and marked them. Now I created different shapes for each possibility, like for
example a smiley face, a heart and a triangle and cut them out of electrical tape. These
codes will allow our spotter and driver to know what to collect for that round without
alerting competing teams.
Hannah Making Test Display Dial (left) and Finished Display Dial
Mounted on Robot (right)
Note Code Symbols and Placement of Sensor Finger Unit
23
Finally I had to mount both pieces on the robot. Both things had to go on the arm.
To get the information I wanted to attach the metal fingers below on the arm. I took a
piece of wood and tried out the angle it needed to be cut in order to fit correctly into the
data sensor port when the robot arm is going down in it. To attach the Data Port Display
Dial I cut two metal peaces, drilled two holes into each and on the place it should go and
screwed the metal on the Data Port Display Dial. Then I bent both metal pieces at an
angle of about 90 degrees, drilled a hole into it, marked the hole-places on the robot arm,
drilled a hole there and screwed the Data Port Display Dial on the robot arm. See
Attachement 3 for the Symbol Key.
To test these both things and the program, we took all to the mall day and tried it
on this field. We were happy to find out that it worked.
Detail of Sensor Finger Unit
d. Considerations of DC Motor Torque and Worm Gears
As the claw developed into a multiple unit piece of equipment (gizmo grabber,
Frisbee and cone grabber, rotational motor) it became apparent that we needed a
24
combination of the small motor provided and a gear system to increase its power. The
questions were:
1. How much weight did we have at what point on a moment arm to lift?
2. What was the maximum power of the small motor?
3. Would the small motor lift the weight without assistance?
4. What gearing would we need to augment the small motor to handle our load?
The answer to the first question was reasonably easy to find with a fish scale; the
arm unit weighs 26 ounces. Power and torque became the next issue we looked at.
Information from the Internet (Attachment 4,5) provided us some background. We
downloaded the small and large motor specifications from the BEST Website
(Attachment 6,7) Our engineering mentor spent time with the team explaining the
information and assisting us in calculating our gear requirements. These graphs were
particularly useful to our understanding the process:
25
Using the data provided we estimate that maximum power will be at approximately ½ of
the no load speed (45 RPM). Basic data considered:
No load speed
90 RPM
Stall Torque
9.49 in/lbs
Stall Current
2.39 amps
Weight of claw
26 oz
Length of arm
20 inches
RPM for max power
45
Required gear ratio
66:1
Initial calculations and tests showed that the small motor required approximately
40% of the power needed to lift out claw. Therefore, we needed to at least double the
motor power with a gear system. Again, our engineer mentor took us through the process
of calculating what gear system we needed. We determined that 66:1 would work but be
slow and 50:1 was faster but provided the only the bare minimum power needed.
To make the worm gear, we cut 1 ½ inch circles out of the polypropylene and
screwed them together to make a 4 inch long tube. Using a jig we built we used a radial
arm saw to cut the teeth while turning the jig. To make the flat gears (Attachment 6) we
built a circular gig and attached a 5 inch and 7.5 inch diameter circle of polypropylene.
Again, we used the radial arm saw very carefully to cut the 3/16x3/16x3/16 teeth. We
turned out a 4 inch worm gear with 3/16 teeth wound around it. We tested this with a 5
inch, 50 tooth flat gear and a 7.5 inch, 66 tooth flat gear. The 50 tooth gear would not do
the work, the 66 tooth-while slower- provided all the power we needed.
26
VIII: Test and Optimize
a. Gearbox placement:
Josh suggested that if we expanded the hole made for the gearbox then rotated the
gear box 45° we could increase the arm length while still allowing for compliance. This
would also increase the height the robot could reach by three inches. Daniels claw was
altered to grip multiple eggs by hammering two humps into the metal. The humps were
roughly ½ an inch in height there was the added addition of drilling holes into the top of
the humps to put screws through to help grip items. We changed cardboard box to wood
for greater stability and durability.
Gadget Box with
Servo Mounted on
Final Robot
Kevin‟s claw could only pick up eggs and a few cones so we mounted Danny‟s claw on
top of it for Frisbees however previously stated errors in design forced us to replace
Danny‟s claw with the Frisbee grabber contributing to our strange antler like design.
b. Josh’s Claw
The Frisbee grabber was designed as a solution to the failings of Daniels claw. It
was initially designed to pick up Frisbees and to be able to be mounted on the back of
27
Kevins claw. It is made out of two long pieces of lexan. Attached are carefully space four
short pieces that are curved to help grip the Frisbee. Mounted on the insides of the main
shafts are two metal grips with rubber surfaces for picking up cones. We later mounted
two thin pieces of lexan onto the claw that have rubber bands on them to help secure the
cones in place while still being flexible. The servo mounted on the claw is attached to a
slide mechanism that opens and closes the two sides to grasp either the cone or the
Frisbee. Using the system, a Frisbee is simple trapped in the jaws, lifted up and release
on the cone. Cones are grasped with the inside grips and then rotated with the claw motor
and lifted so as to be in position for placement
.
Basic Claw: Note
Slide Mechanism
for Movement
Claw with Cone:
Note Small Fingers
to Hold Cone
Claw with Frisbee: Note
Curved Brackets Holding
Frisbee
Assembly:
Drive wheels mounted on the base were moved forward to increase traction when
the arm was extended. A new wooden block was built to mount the rotational device
motor more effectively. The gadget collection box was mounted beside the gearbox and
the servo adjusted. The data port sensor was mounted under the arm at the correct angle
for port interface and the display dial mounted on top of the arm. The final claw (Kevin‟s
28
gizmo grabbers on the bottom and Josh‟s Frisbee/cone grabber on the top) was lightened
up and mounted to the rotational motor.
The reed switch was placed on the outside of one gizmo grabbers to be in place to
quickly sense which gizmo was underneath. Software was re-loaded and tested- all
systems worked. Now, it was time to practice.
c. Driver Training: For the driver competition, we asked everyone if they
wanted to drive the robot. Any volunteers that showed interest in driving were put
through trials to determine their driving skills. The contest would be an average round of
standard competition. The top five scores moved on to qualify for driving. The
contenders would go on to practice as a unit for the real competition. In addition to the
trials, the feedback that the drivers would give the engineers is valuable. Any changes
that would need to be made to the robot could be after our initial driver training.
We carefully analyzed the game and developed our offensive strategy that is a
combination of moving the maximum number of gadgets while still processing gizmos.
Speed and 100% accuracy of product selection are the key issues. We know that with our
Data Port Sensor we have the defective information immediately and will be able to
optimize our plan. Driver and Spotter Strategies are listed below
Driver steps:
1. trailer to dock
2. connect to data port
3. 1st load of golf balls
4 . score all cones
5. move trailer to recovery area
29
6. If spotter not done scoring gadgets get gizmos
7. If done move two more loads of golf balls
8. after that begin working on eggs 4 per cone
9. seal cones with Frisbees
Spotter steps:
1. watch robot for defective info
2. sort golf balls on floor
3. send effective golf balls through tube
4. put defective into trailer
5. repeat
This year‟s challenge did not require much defensive strategy since all robots
would be on a separate field. However for a slight advantage defensively above the other
teams competing in that round we built a sensor on the robot, so that we could easily tell
which products were defective and which ones weren‟t. This would save us much time
so we could gather more eggs or golf balls.
Our offensive strategy this year could be summed into one word, time. We
wanted to be able to do anything we wanted as fast as humanly possible with our robot.
Our first challenge was the gadgets. We needed a way to be able to gather them without
having to spill them all over the floor and gather them up one at a time. To do this we
made “The Box”. The Box was a big wooden container that was attached to the robot,
and when we wanted golf balls we would roll it under the dispenser and we would be
able to carry over fifty golf balls.
30
Once we‟d dealt with the gadgets we moved onto the gizmos. To deal with these
we made several different claw designs all of which have been explained already. We
took these and tested them numerous times to see which worked best. Finally we decided
that we would use “The Chupa-Beast”. Not only could it pick up a gizmo quickly and
efficiently and dispense it, but it could pick up two. Another challenge that went along
with the gizmos was being able to pick up and turn over cones so we would be able to
score the gizmos that‟d we‟d worked so hard to collect. Also we needed a way to pick up
the Frisbees so that we could maximize our scoring potential.
This came from the same claw design luckily which we call “Josh‟s Frisbee
Grabber.” It was able to easily turn over cones and top them with a Frisbee after we‟d
gathered as many gizmos as we‟d needed.
After all this we tested our final design. The robot worked just as we‟d wanted it
to when building it. All that was left to do was practice driving to robot so that our
drivers felt comfortable with it.
The final five competitors were given an example of our unique strategy which
would ensure a perfect score each round. From there they practiced every available
opportunity with their specific spotter. Then each person‟s style and strengths put them in
their own rounds that they were responsible for. This built personal relationships between
spotters and drivers as they practiced through frustration and often laughter.
IX. Final Product Construction
As always, the Metal Mustangs engineers have provided us with a robot that if
taken to a different time period it would be considered demonic and then burned. It
resembles an antlered dinosaur with a sideways mouth. While it is compact and efficient
31
it is incredibly complex. With individual components for every function using a
combination of Kevin‟s Claw and the Frisbee grabber it is mounted on a rotating claw
holder using an articulated arm mounted on a U-shaped base.
The SEHS
Gravedigger
To simply summarize, this complex, yet easy to employ machine has
demonstrated the ability to achieve every software and hardware goal outlined by the
team perfectly. This is an awesome robot!
32
Appendix Table of Contents
Appendix
Page Number
Appendix 1 Brainstorming
Meeting minutes and Pen and Pencil Sketches
35- 38
Appendix 2 Computer Software
39
Appendix 3 Symbol Key
40
Appendix 4 Motor Calculations
41
Appendix 5 Motor Speed Torque Curve Calculation
42
Appendix 6 Motor Diagrams
43
Appendix 7 Worm Gear Calculations
44
Appendix 8 Sample Sign in Sheets
45-46
BEST Team Demographics form
47
33
Appendix 1 Brainstorming
Meeting minutes and Pen and Pencil Sketches
34
35
36
37
Appendix 2 Computer Software
38
Appendix 3 Symbol Key
39
Appendix 4 Motor Calculations
40
41
Appendix 5 Motor Speed Torque Curve Calculation
42
Appendix 6 Motor Diagrams
43
Appendix 7 Worm Gear Calculations
44
45
46
BEST Team Demographics - 2010
In order to obtain the most complete information on student/team participation in BEST, the
completion of this form by each team is now a required part of the Project Engineering
Notebook submitted at the local hub competition (form not required for the Regional
Championship).
Please help BEST by giving us complete information in the fields below. It should be completed
just prior to submission of the notebook for judging.
School Name: Stanhope Elmore High School
Name of town/city: Millbrook
State: AL
Type of school (check the box):
Private
X Public
Type of school (check the box):
Middle/Jr. High
X High School
Home school
K-12
Other:
Other:
Which most appropriately describes the student population at your school:
1 to 399
400 to 799
800 to 1199
X 1200 to 2000
greater than 2000
Number of students on BEST team by grade:
K - 5th: 1
6th:
7th:
8th:
1
9th: 6
10th:
2
11th:
7
12th: 11
Number of students on BEST team by race (optional):
African-American:
Hispanic:
4
3
American Indian:
Asian:
Caucasian: 21
Other:
Total number of students on team: ___28____
Number of males: ___16___
Number of females: __12___
Total number of students who worked on the robot: __11________
Total male: __7_______
Total female: ______4_______
Total number of students who worked on the BEST Award: ____28_____
Total male: __16______
Total female: _12________
Approximate number of students likely to pursue careers in engineering, science, math, or technology:
Total # of male:
7
Total # of female: 3
Total number of adult team mentors (NOT including teachers): 3
Please list the companies, businesses or organizations that sponsored your team this year, INCLUDING
those that provided team mentors:
UPS
Kiwanis
Philly Connection
City of Millbrook
Thanks from BEST Robotics!
47