The School:
Monterey Peninsula College
TEAM MATE
The Dedicated Students
Matt Gardner
Greg Kaufman
Aaron Barchie
Matt Bennett
Josh Mickler
Charles Ransom
Penelope Ross
Kyle Sheijak
The Intrepid Instructors
Frank Barrows
Tom Rebold
Figure #1: Team Members with X-Wing Design Prototype
BOT MATRIX RELOADED
Monterey Peninsula College
Table of Contents:
1. Introduction
2. Prototype Design
3. Design of BOT MATRIX Reloaded
a. ROV Name
b. Motor Configuration
c. Structure
d. RUSTI Lift Device
e. Motors and Propellers
f. Tether Wire
g. Control System
h. Cameras
4. Design Conclusions
5. Improvements
6. Lessons Learned
7. Conclusion
8. Budget
9. Acknowledgements
10. Appendices
Figure #1:
Figure #2:
Figure #3:
Figure #4:
Figure #5:
Figure #6:
Figure #7:
Figure #8:
Figure #9:
Table #1:
Table #2:
Table #3:
Table #4:
Team Members with X-Wing Design Prototype
BOT Matrix Reloaded.
X-Wing Prototype
X-Wing Motor Configuration
Slanted Wings
Size Design of BOT Matrix Reloaded
Two views of the RUSTI Lift Device
Variable Air Volume Lift Device
Bilge Pump Motor with Propeller from Sea Eagle III
Length of Pipe Needed to Achieve 10 lbs of Buoyancy
Calculated Resistance of Variable Gauge Wire at Variable Lengths
Power/Voltage Loss
Remaining Power/Voltage Through Tether (Using 12V Power Supply)
Abstract:
The mighty Titanic cruises almost silently through the smooth black water of the North
Atlantic. Only the low rumble of engines vibrating throughout the hull and the gentle swishing
of the bow cutting through the water disturb the peaceful star filled night. Out of the dark
gloom ahead of the great ship, a shape forms, ghostly white in the haze. Iceberg.
The dauntless ROV RUSTI cruises almost silently through the smooth black water far beneath
the North Atlantic surface. Only the low whine of it electric engines and bright floodlights
disturb the peaceful blackness of the depths. Out of the dark gloom ahead, a shape forms, like
a gray knife in the black depths. Titanic.
The instructor presents the news to the students. An ROV named RUSTI is disabled, and it is
the student’s assignment to design a rescue ROV. Creating a design prototype is the first task,
and with the mission specifics in mind, students divide into groups and assemble prototype
models of varying designs. Only weeks later, one prototype is decided upon, a unique X-wing
design with all motors pushing in the same direction. The best time for this prototype to rescue
a small scale RUSTI mockup is 1:57. With the prototype design decided upon, components are
purchased and assembled. Four powerful motors, a compressed air lift device to offset
RUSTI’s weight and two cameras to provide forward and reverse views, all fitted into a PVC
frame. A novel design for a novel mission. Victory or defeat.
Figure #2: BOT Matrix Reloaded with RUSTI
Introduction:
The mission goals of the Open Class Competition are to travel into the wreckage of the
Titanic to recover a disabled ROV known as RUSTI. The background story behind the
designated task is that RUSTI became trapped in one of the Titanic staterooms when it was
damaged and its watertight canister flooded. Attempts to retrieve the ROV by winching it in
caused the tether to break approximately 2 meters above the ROV, leaving it totally helpless.
An ROV needs to be constructed to travel down to the Titanic, enter the stateroom through a 4
ft by 4 ft wide opening, attach to the disabled RUSTI and return the disabled ROV back to the
surface.
Although for this competition we will not be traveling to the bottom of the North
Atlantic Ocean, the challenges will be similar. Our mission goals are to design and build an
ROV that can descend to a depth of 15 feet, enter a room through a 4 ft x 4 ft opening, retrieve
a disabled device with the dimension of 2 cubic feet, and return it to the surface. There are a
number of design challenges to this mission. With its watertight control box flooded, RUSTI
weighs 4.5 kg (10 lbs) submerged. Power limitations for the rescue ROV are 48 Volts and 40
Amps. With those limitations, it is unlikely that motors alone will be sufficient to lift RUSTI
from the bottom; some other lifting device will be needed. There is also a time factor. The
team that completes the task the quickest receives the most points, which will help to win the
overall competition.
Prototype Design:
After the initial mission was
outlined, a number of different design
proposals were considered. To determine
which design to build, we divided into subteams and constructed a number of halfscale prototypes. A half-scale RUSTI was
built, and the design winner would be the
prototype ROV that was most proficient in
entering the Titanic, grabbing the half-scale
RUSTI, and returning it to the surface. The
winner of the prototype contest was the Xwing design (Figure #3), with a best time of
1 minute and 57 seconds, but with an
Figure #3: X-Wing Prototype (rearview)
average retrieval time of approximately 5
minutes. The predominant features of the
successful prototype were an
X-wing motor configuration and a RUSTI lift device that used compressed air. The prototype
control box used 4 double pole, double throw switches, but this system was difficult to work
with, and it was decided that a joystick or button control system was optimal. With a prototype
to work from, we began to order our full-scale parts and begin construction.
Design of BOT MATRIX RELOADED:
ROV Name:
BOT Matrix was the name of the Battlebot ROV constructed by TEAM MATE in
2001-2002. It participated in, and won, the first ever Discovery Channel Underwater
Battlebots Competition – Depth Charge. In homage to our ROV’s predecessor, and in honor of
the recently released Hollywood movie, we settled on the name BOT Matrix Reloaded.
Motor Configuration:
One of the most interesting design characteristics of BOT Matrix Reloaded is its motor
configuration. TEAM MATE elected to use the X-wing motor configuration design.
Four motors are used, with
one placed in each of the
upper left, upper right, lower
left and lower right edges of
the ROV (Figure #4). All
four of these motors push in
the same direction. This uses
a different principle than the
standard ROV Motor
Configuration that has motors
that move the ROV in the
horizontal plane, motors that
move the ROV vertically and
motors to provide pitch or
roll. Having all four motors
pushing in the same direction
Figure #4: X-Wing Motor Configuration
has a number of advantages,
and some disadvantages, over
the standard design. Overall however, we can utilize the advantages and minimize the
disadvantages of this design to give BOT Matrix Reloaded the best possible performance.
The X-wing design’s main advantage is that all motors push in the same direction,
maximizing power for straight-line movement. The biggest disadvantage to overcome was
moving in a direction other than straight forward. We accomplished vertical movement by
creating an ROV with zero stability. Stability is defined as the tendency of a vessel to return to
its original position after it has been inclined due to external forces. Stability is dependent on
the location of the center of gravity of the craft (ballast) versus the location of the center of
buoyancy of the craft (flotation). Our ROV has sufficient flotation to give it slightly positive
buoyancy, but the flotation is located in the exact center of the ROV to give it zero stability.
Therefore, when the pilot moves the ROV into a nose down configuration, it stays in that
position. To move our ROV vertically, or in any desired direction, we simply point our nose in
the desired direction and accelerate.
After designing and testing our prototype with zero stability, we elected to alter the
design slightly. We determined that with zero stability, our ROV would tend to roll around its
central axis. Although our design can technically be driven with any side facing any direction,
ROV roll tends to disorient the pilot. Motor placement on the ROV no longer matches the
orientation of controllers on the control panel, which is very disorienting to the pilot. We
elected to give the ROV very little stability, so that if left alone for five or ten seconds, the
ROV would tend to right itself to the proper orientation. With this engine configuration,
matched with this buoyancy design, we can maintain orientation long enough to easily move
up or down, but if rotational problems occur, our ROV will slowly right itself back to standard
orientation.
Overall, TEAM MATE thinks the X-wing design is the most beneficial fourmotor design. Combined with a very low-stability buoyancy design and a proper control
system, the design disadvantages are minimized, while the increase in power from having
all four motors pushing in the same plane should give a measurable advantage. We hope
that our thoughts behind this design theory work well in the competition.
Structure:
TEAM MATE designed our ROV’s structure with shape, size and durability in
mind. In prototype testing, one of the toughest piloting tasks was to maneuver our
prototype ROV, with a 21-inch crosssection, through the half sized Titanic
opening that was 24-inches in diameter.
Unless the pilot entered the opening
exactly centered, the outer ‘wings’ of the
X-wing prototype would impact and catch
on the doors. To overcome this dilemma,
we designed our outer wings with a 45degree angle in them (Figure #5). If our
pilot enters the Titanic off-center and
impacts the doorway, the 45-degree angle
will allow the ROV to slide through the
Figure #5: Slanted Wings
opening instead of catching on it.
The second structural design
characteristic works towards the same end.
We designed our ROV within specific size
tolerances. A smaller ROV size would
facilitate our passage through the 4 ft
diameter doorway. However, the wing
spread had to be larger than RUSTI, as our
goal was to drive our nose, which contains
our lift device, inside RUSTI while the
wings banged up against the side of
RUSTI (Figure #6). Constructing BOT
Figure #6: Size Design of BOT Matrix
Matrix Reloaded to the proper size allows
Reloaded
us to more easily complete the mission.
Strength was also a key design characteristic. BOT Matrix Reloaded is built from
PVC and there are many joints and elbows. Each one of these represents a weak point.
Running into a wall or floor, or simply the powerful motors pushing the ROV through
water resistance could put undue stress on the PVC connections. A single failure due to a
loose joint connection could cost us the competition. Therefore, we decided to make
every connection as strong as possible. We considered PVC glue, but gluing the joints
together creates brittle connections. Glue has no give whatsoever, and instead of flexing,
the frame structure is much more likely to snap and break. Instead of glue, TEAM
MATE elected to use screws. Screws allow the PVC joints to flex and bend slightly,
while still holding solid. Every joint on the ROV was strengthened with a single screw.
A few pounds of weight were added to our ROV from the many screws used, but the
decreased chance of catastrophic failure greatly offsets the problems of increased weight.
232 screws were used to connect the joints of BOT Matrix Reloaded.
RUSTI Lift Device:
Given the 48 Volt, 40 Amp power restrictions, engine power alone will be hard
pressed to lift 10 lbs of RUSTI out of the Titanic. TEAM MATE decided that using air
as a variable buoyancy system would be needed to provide the lift for RUSTI, while our
motors simply provided movement once we had offset the weight.
Mathematical calculations determined that we would need approximately 4545
cubic centimeters of air to lift 4545 grams (10 lbs) of RUSTI, so we needed to design our
air bag with that volume. Our motors would be able to handle some excessive positive or
remaining negative buoyancy, but we wanted a quick way to make RUSTI as close to
neutrally buoyant as possible. In order to hold a certain amount of air, we decided to
encase our air bag, a motorcycle inner tube in this case, inside ABS pipe (Figure #7).
The ABS pipe provides a hard exterior wall for the inner tube to push against, restricting
Figure #7: Two views of the RUSTI Lift Device. An inner tube can be
inflated to 10 lbs positive in the outer loop of the Lift Device
over-inflation, which allows us to determine the proper volume for the lift device.
Drilling holes in the lift device pipe allows the air bag to deflate when it is not filled with
pressurized air, as the outer water pressure exceeds the internal air pressure. This entire
encased air-lift system solved the problem we experienced with our prototype design.
Our prototype air bag was not enclosed in pipe. It would over-inflate and our ROV,
attached to RUSTI, would rise too quickly. Instead of exiting through the doorway, our
ROV would shoot to the roof of the Titanic stateroom. There was a constant effort to
balance air inflation to deflation in order to achieve a proper balance and make smallscale RUSTI perfectly neutral. To overcome this problem experienced with the
prototype, we decided to use the ABS pipe to give us exactly the amount of lift needed.
We looked at a number of pipe diameters, but eventually settled on 3-inch ABS pipe.
The diameter we settled on was determined by the length of pipe we would need to
achieve 10 lbs of lift. Calculations revealed that we would need approximately 1 meter
of 3-inch ABS to lift 10 lbs, which fit into our initial size design parameters.
Table #1: Length of Pipe Needed to Achieve 10 lbs of Buoyancy
Pipe Diameter (in)
Pipe Diameter (cm)
Pipe Radius (cm)
4 inches
3 inches
2 inches
10.16 cm
7.62 cm
5.08 cm
5.08 cm
3.81 cm
2.54 cm
Pipe Area (cm2)
Pi * Radius 2
81.07 cm2
45.60 cm2
20.27 cm2
Pipe Length Needed
4545 cm3 / Area
56.06 cm
99.66 cm
224.24 cm
In order to make our lift device more versatile, TEAM MATE wanted to be able
to alter the amount of lift provided. To do this, we allowed the volume of air encased by
the air bag to vary by shifting the plug. The plug is simply a small hose clamp that
tightens the inner tube around the air hose. By simply unscrewing it, and adjusting its
position, we can vary the volume of air entrapped (Figure #8). If we want less lift from
our air bag, we shift the plug so only 90 cm is inflated, giving us approximately 9 lbs of
lift. To increase lift, we shift the plug so 110 cm of the inner tube is inflated, giving us
approximately 11 lbs of lift.
Overall, we believe our RUSTI Lift Device will work well. We can easily change
our ROV’s buoyancy from neutral to positive 10 lbs, which will allow us to quickly
offset the weight of RUSTI. We will be neutrally buoyant at all times, and be able to
interchange between the two buoyancy states quickly.
Motors and Propellers:
Power wins contests. That is the belief of TEAM MATE. Therefore, we looked
for the most powerful motors we could find that would run on 48 Volts and 40 Amps. In
the past, bilge pump motors have always served our group well. The biggest benefit of
bilge pump motors is that they are built watertight. No waterproofing is needed. The
other benefit of bilge pump motors is that under a removable exterior, they have a
rotating shaft that turns an impellor. By simply removing the impellor and attaching a
propeller to the shaft, we had a working, waterproof motor.
TEAM MATE looked for the most
powerful bilge pump motor on the market.
The RuleTM 3700 GPH (Gallons per Hour)
bilge pump motor fit our needs perfectly.
(Figure #9). It is rated to run at 32 Volts
and 6.9 Amps. With four of these motors
wired in parallel, the total amperage is
approximately 28, well below the 40-amp
limit.
The 3700 GPH bilge pump has a
fairly large diameter, approximately 5
inches, which requires that a fairly large
propeller is used to get ideal water flow.
The online model store we usually buy
propellers from, www.harbormodels.com,
did not have any propellers of the
Figure #9: Bilge Pump Motor with
appropriate size. Fortunately, our MATE
Propeller from Sea Eagle III.
department has a number of larger ROV’s
on the premises. In December of 2002,
the U.S. NAVY donated two Sea Eagle III ROV’s to TEAM MATE. The Sea Eagle III’s
have 3-bladed propellers approximately 6-inches in diameter, a perfect size for our
motors. We removed six of these propellers to be used by our four motors, giving us two
spares.
Originally, TEAM MATE had decided to run our engines on 36 volts. Although
only rated for 32 volts, the 3700 GPH motors should operate at a slightly higher voltage,
and it was easy to obtain 36 volts by wiring three car batteries in series. The voltage
increase would increase amperage slightly, but not enough to push us over the limit.
However, we found that over-propping quickly became a problem. Over-propping a
motor is when the rotation of the shaft is significantly slowed due to resistance caused by
the propeller pushing water. For our initial power test, we operated the bilge pump motor
at 12 volts, and had 7 amps running through the wires. At 24 volts, amperage shot up to
17 amps. At 36 volts, amperage for each motor increased to 28 amps. Since each of the
four motors is limited to 10 amps, we could only run the motors at 1/3 the intended
voltage. However, even at 1/3 the intended voltage, the motors exhibited sufficient thrust
to move our ROV. TEAM MATE finally settled on 16 volts to maximize our power
output. At this voltage, each motor ran at approximately 9 amps, just below allowable
amperage.
Tether Wire Selection:
In researching wire for use in our tether, we found a good bargain on 14 AWG
(AMERICAN WIRE GAUGE) speaker wire. Before we went ahead with the purchase,
however, we wanted to make sure that the 14 AWG wire would be suitable in our tether
and that we would not lose too much power or voltage due to the length of wire required.
Our plan was to use 60 feet of tether (120 feet round-trip). Also, our selected
motors (bilge pumps) were rated at 32 volts and 7 amps. Using this data and an AWG
table, we calculated power loss and voltage drop for our system to verify which gauge
wire would be best to use. We calculated power and voltage loss for varying tether
lengths (100-150 feet, in increments of 10 feet) and varying amperage (3 – 10 amps).
Our first calculation was wire resistance for various lengths of wire.
Table #2: Calculated Resistance of Variable Gauge Wire at Variable Lengths
AWG
Wire
Gauge
10
11
12
13
14
15
16
17
18
From AWG
Defined
Table
Round Trip Cable Length Resistance
[Ohms] per # of [ft]
Ohms/ft
1000
0.9989
1.2596
1.5883
2.0028
2.5255
3.1845
4.0156
5.0636
6.3851
# of feet
100
110
120
130
140
150
0.100
0.126
0.159
0.200
0.253
0.318
0.402
0.506
0.639
0.110
0.139
0.175
0.220
0.278
0.350
0.442
0.557
0.702
0.120
0.151
0.191
0.240
0.303
0.382
0.482
0.608
0.766
0.130
0.164
0.206
0.260
0.328
0.414
0.522
0.658
0.830
0.140
0.176
0.222
0.280
0.354
0.446
0.562
0.709
0.894
0.150
0.189
0.238
0.300
0.379
0.478
0.602
0.760
0.958
Next, using the resistance calculated above, we calculated the power draw over a
range of amps from 3 – 10 amps (our selected motor has a 5.0 amp [nominal] and 7.0
amps [maximum] draw). Originally, we were planning on using 36 volts (three 12 volt
batteries in series) since our motor was rated for 32 volts and drawing 7 amps. The
power draw for this configuration would be 252 watts. When we modified our bilge
pump to run with a propeller instead of the designed impeller, our amperage draw went
up to 28 amps per motor, well above our per motor limit. We tested our motor running
off of just 12 volts and found that the amperage came down to 7 amps, within the power
limit given for the competition. 12 volts and 7 amps gives us a power draw of 84 watts.
Knowing our power draw from a 12-volt battery, we next calculated the power loss and
voltage drop that would occur from a variety of gauges of wire. The full calculation
tables can be found in Appendix #1. Table #3 shows power loss and voltage drop over
14 and 16 AWG wire at 7 amps. The values in red specify the data we used to select our
tether wire.
Table #3: Power/Voltage Loss
AWG
100 ft
Power Loss Of Wire @ 7 Amps
110 ft
120 ft
14
12.375
13.612
16
19.676
AWG
100 ft
21.644
Voltage Drop @ 7 Amps
110 ft
120 ft
14
1.768
1.945
16
2.811
3.092
14.850
23.612
2.121
3.373
130 ft
16.087
25.579
130 ft
2.298
3.654
With knowledge of the power loss we can verify that either 14 or 16 AWG wire
will suffice for our tether. Looking at Table #4, we decided that 14 AWG would work
best for our tether since it minimizes power loss and is also the most cost effective.
Table #4: Remaining Power/Voltage Through Tether (Using 12V Power Supply)
AWG
14
16
(Using 12 V
Power Supply)
AWG
14
16
100 ft
71.625
68.396
Remaining Power @ 7 Amps
110 ft
120 ft
69.150
70.388
65.275
66.836
130 ft
67.913
63.715
Remaining Voltage @ 7 Amps
100 ft
10.232
9.771
110 ft
10.055
9.548
120 ft
9.879
9.325
130 ft
9.702
9.102
500 feet of 14-gauge double stranded speaker wire was purchased. This gives us
twice the necessary length of wire, four tether wires of 60 feet each, but the extra wire
will be used for replacement in case of emergency.
Motor Control System:
Our motor control system consists of five parts from the joystick controller
through to the motors. The five parts are as follows (Figure #10):
1. Joystick
a. Playstation gamepad controller. (Main Controller)
c. Mechanical Double Pole Double Throw switches (backup controller)
2. Basic Stamp (Parallax Inc.)
3. Control Board (self designed)
4. H-Bridge Control Boards (1 per motor) (Minn-Kota Riptide)
5. Bilge Pump Motors (Rule 3700 GPH)
Figure 10: Control System Diagram
Please refer to Appendix #2 schematic for the connections between the joystick, Basic
Stamp, Control Board and H-Bridges.
Joystick Controller:
A Playstation Gamepad with analog controls was chosen since it would give us
two small analog joysticks (allows speed control of motors) and for the large number of
buttons allowing us to customize individual motor control. The other advantage of using
this type of controller is that all the signals/data from the controller are digital, so there
was no need to interpret analog signals into our digital Basic Stamp. Digital signals can
be fed directly into the Basic Stamp. To understand the Playstation interface, we used a
great website set up by AJ McCubbin: http://home.quicknet.com.au/andrewm/psx/psxcont/index.html
For safety, in the event that our main controller fails, we have a simple (double
throw double pole) switch control box with direct connection to the motors. Using this
backup controller we will only have forward-backward direction control and we will lose
speed control since the mechanical switches bypass the Basic Stamp and Control Board.
We were still successful using this simple control box during prototype testing.
Riptide H-Bridge Controllers:
Each motor requires an h-bridge since they apply the actual power to our motors
based on which direction and speed we have defined with our joystick. The h-bridge
controllers we are using were purchased from Minn-Kota last year to control larger
trolling motors used in a different ROV competition. While they were designed for the
larger trolling motors, they still have the right specifications to run our bilge pump
motors. In reusing the h-bridge controllers will save both time and money.
Basic Stamp / Control Board:
The Basic Stamp (Figure #11)
sits between our joystick and the control
board interpreting the digital signals
from the joystick and creating signals to
control our speed and direction. For
direction control (Figure #12), the basic
stamp controls a relay that switches
between the forward and backward
direction.
Figure #12: Motor Direction Control
Figure #11: Basic Stamp
For speed control, the Basic Stamp produces a PWM (pulse width modulation)
signal. A PWM allows our Basic Stamp to produce an analog signal even though it itself
is a fully digital device. This analog signal is then passed through our speed control
electronics (Figure #13) and into the Riptide H-Bridge control running our motors at the
desired speed.
Figure #13: Single Motor Speed Control
Combining the two signals through an h-bridge controller we can drive a motor
forward or backward and we can adjust the speed from standing still to full thrust for
each motor.
TEAM MATE believes that an easily workable control system is vital to this
competition, but especially so to our design. We need to be able to quickly line up to
move through the doorway, turn once we are inside the Titanic and make fine controls to
push our nose, with the lift device, into RUSTI. These are the mission tasks that will take
the most time, and precise control can greatly reduce the time needed. Our joystick
controller will allow us to have fine control, with both independent speed and directional
control for each motor. However, if that system fails, we also have our double pole,
double throw switch box that can be hooked up rapidly. It is not as efficient, but will
allow us to complete the mission.
Cameras:
TEAM MATE chose to use a pair of CVC6990 cameras to visually guide our
ROV underwater. We tested this camera type against a number of other camera types (X10, Arianne) that we had in the lab to see which performed best. Testing included
aperture width, visual acuity at short range, visual acuity at long range and the ability to
see laser points. One design thought was that laser pointers, mounted on each wing and
facing forward, would help us navigate by pointing to the location each wing would
impact a wall. However, this proved to be unnecessary after we had tested for it and laser
pointers were not used on BOT Matrix Reloaded.
The CVC6990 camera proved to have an aperture width of approximately 50
degrees in air and 42 degrees in water. Close in visual acuity was determined by
attempting to read the word ‘Test’ written on a 3-inch by 5-inch note card. The
CVC6990 camera could read the card as close as 2 feet and as far away as 16 feet in air.
This camera also had good long-range vision. It could see a length of ¾ inch PVC pipe
out to a distance of 75 feet. The X-10 had a much thinner aperture width, approximately
30 degrees in air and 25 degrees submerged. The visual acuity was also not as good as
the CVC camera. Vision was grainy, both at short and long range. The Arianne camera
was color and had an aperture width similar to that of the CVC, but visibility beyond 15
feet was vague. Overall, the CVC6990 camera proved to have the best visual acuity of
all the cameras tested.
BOT Matrix Reloaded uses two CVC6990 cameras. While traveling to the
Titanic, we plan to operate in forward motion. Thus, one camera is set facing forwards.
It will allow us to navigate forward and also allow us to watch over the operation to
attach to RUSTI. With good vision at both long and short range, it should work fine for
both navigation and operational purposes. After we have captured ‘RUSTI’ we may
drive forward or reverse, whichever direction allows easier exit of the Titanic. Our
second camera is fitted facing the rear, allowing us to navigate in reverse. Our TV
monitor can look at either camera or be set up as a split screen, allowing both views to be
seen. Originally we had considered more cameras, perhaps one on every wing, but
monetary cost, tether weight, and the ability to split screen that many cameras was
prohibitive. We believe that these two cameras will allow us to navigate BOT Matrix
Reloaded as needed.
Design Conclusion:
Each component of our ROV was designed specifically for this competition.
Although different students specialized in various components, there was enough
interaction that everyone is familiar with each system, and each system can easily
integrate onto the overall structure. Hopefully all our systems will work well enough in
conjunction to rapidly retrieve RUSTI from the Titanic stateroom.
Improvements:
The two major tasks that could have been improved were fund-raising and early
purchase of vital equipment. These two are tied together since funding earlier in the
timeline would have allowed us the money to purchase certain equipment earlier.
However, funding agencies work around their time, not around our desired timeline.
Getting funding requests in early, knowing there would be a delay, would have given us
more time to build our ROV, and we would not have to cram in the final weeks. For
TEAM MATE, we had to delay in purchasing our expensive motors until funding came
in. Unfortunately, before we knew the size and shape of our motors (we cut them down
from their original size) we could not build the frame. Without a constructed frame,
other systems such as the Lift Device could only be partially constructed. Before we
knew the power requirements of the motor, we could not purchase wire. Overall, getting
funding early would have greatly improved our efforts.
Lessons Learned:
Teamwork is important. Although we divided up into workgroups, with certain
individuals working on certain systems, discussions on what the best design or best way
to construct the desired component is very beneficial. In many instances, suggestions
from other team members proved to be the best design, and those suggestions were
quickly incorporated. One of the best examples of this was in our prototype. The air
hose we were using was very stiff and created rotational torque on our ROV, which
prevented the prototype from righting itself after a turn. The torque pressure of the air
hose overcame the minor amount of stability we had added to the prototype, keeping our
ROV askew. The first fix for this system was to use a swivel type mechanism built into
the air hose. This consisted of two metal pieces, one of which fit inside the other and
swiveled. The problem was that this swivel did not twist very well due to friction, and
even worse, it was not watertight. A teammate suggested cutting a section of inner tube
and clamping it over the swivel to eliminate water intrusion. The inner tube would
provide sufficient twist to allow some swivel of the mechanism and also would create a
watertight seal. Looking at the situation, the counter-suggestion was that we could totally
do away with the metal swivel. We simply cut the stiff air hose, and rejoined them with a
small section of inner tube. All the rotational torque from the airline in the tether was
neutralized by the flexible inner tube, and watertight integrity was maintained. We had a
highly functional, zero cost design. This was one of many cases where alternate design
suggestions led to an overall improvement. Teamwork helped us create and design a
better ROV.
Another lesson learned was that a timeline, with specific goals marked out for
each week, is a good method to keep from falling behind. TEAM MATE did fall behind
our timeline on many occasions, and we are still running behind schedule in some areas,
but knowing that we are behind schedule is also a valuable tool. We can schedule extra
lab time, stay longer and work harder to make up past goals. A timeline, even one that
we stray from, helps us to reach our goal on time.
Extensive pilot training is another valuable tool. We learned from our prototype
competition and from previous competitions that practicing with the ROV well before the
competition is vital. Practice gives the pilot(s) substantial time to familiarize themselves
with the controls and also serves to give the pilot experience troubleshooting any
problems that arise. With even a few days of experience, the pilot has a better chance of
dealing with and overcoming any obstacles that might occur. Providing ample time for
training is a valuable lesson learned and one we plan to implement before this
competition.
Conclusion:
TEAM MATE is very confident in our design. We are using a non-standard
design, but we feel that the advantages of this design outweigh the disadvantages. We
have designed our ROV to the specifics of the mission, but also allowed for unexpected
potentialities. Our structural design allows us to make it through the door easily. Our lift
device allows us to quickly offset the weight of RUSTI and regain neutral buoyancy. Our
motors provide plenty of thrust to move both our ROV and RUSTI. With all of our
designs built to facilitate a fast mission, TEAM MATE is looking for a good time in pool
competition. We are also looking forward to having a good time in general.
Budget:
The following budget itemizes the expected cost and weight of the ROV. We were able
to save a considerable amount of money over our original expectations by reusing the
control boards, cameras and a good deal of PVC extras from our ROV last year.
We hope to minimize shipping costs by packing several components in our luggage.
Incoming donations currently amount to $500 from MATE (with another $1500 travel
stipend expected) and a generous $2500 from Borland Software Corporation for which
we are extremely grateful.
Cost and weight budget for MPC ROV
Subsystem
Item
Frame
PVC
buoyancy
lights
screws/fasteners
hose clamps
paint
$100.00
$25.00
$0.00
$20.00
$25.00
$20.00
15
10
5
10
2
Electrical
motors
wire
control system
fuses
propellers
$500.00
$80.00
$75.00
$25.00
$50.00
30
25
10
cameras
tether sheath
shipping
$0.00
$10.00
$100.00
10
5
$1,030.00
124
Miscellaneous
Total
Projected Cost
Projected Weight
2
Acknowledgements:
TEAM MATE would like to thank the many groups that sponsored the MATE National
Competition as well as a number of groups and individuals that made donations and
contributions directly to our team. We would very much like to thank:
Monterey Peninsula College MATE Center
Monterey Peninsula College Foundation
Cote Consulting
We would especially like to thank Dale L. Fuller, President and CEO of Borland
Software Corporation for his generous donation to our team. We greatly appreciate his
support. A biography of Mr. Fuller appears in Appendix #3.
Appendix #3: Biography of Major Supporter Dale. L. Fuller
Dale L. Fuller
President & Chief Executive Officer
Dale Fuller is president and chief executive officer of Borland
Software Corporation, a leading provider of technology used to
develop, deploy, and integrate software applications. As president
and chief executive officer, Fuller has complete management
responsibility for the company, delivering on the company’s vision of
enabling a new digital world where customers have the freedom to
develop applications, deploy them anywhere and integrate and
manage them across the enterprise.
Fuller joined Borland in April 1999 with more than 20 years of
experience in general management, marketing and business
development in the technology industry. Presently, Fuller is focused
on extending the company’s leadership in both the development
marketplace and enterprise deployment. Committed to open
standards and platform independence, Borland is one of the few
companies bridging the competing technologies of disparate
architectures – including Solaris, IBM, Java, Linux, Mac, Palm and
Windows – including .Net. Borland’s mission is to help its customers
move into the future without abandoning their past, and Fuller is
driving new technologies that enable customers to leverage and
optimize their previous investments with today’s technology and
tomorrow’s advances and opportunities.
Before being named president and chief executive officer, Fuller was
president and chief executive officer of WhoWhere? Inc., one of the
leading community sites on the Internet, which was acquired by
Lycos. At WhoWhere?, Fuller led the expansion of numerous domain
sites, including Angelfire.com, the fastest growing Internet site of
1998, and MailCity.com, a free email site, as well as increased the
company's consumer reach to become a leading online guide of
people and business information around the world.
Prior to WhoWhere?, Fuller was a vice president and general
manager at Apple Computer. From 1994 to 1996, he was with NEC
Technologies, Inc. as vice president and general manager, Portable
Computer Systems, and was responsible for moving NEC's notebook
computers into the top tier of portable systems and manufacturers.