UTRGV / COLLEGE OF ENGINEERING AND COMPUTER SCIENCE / MECHANICAL ENGINEERING DEPARTMENT

TEAM 8: Wave Powered Autonomous Underwater Vehicle

(Design Process Page)

SDI Students (L-R)	· Javier Benavides · Bryant Chiu · Fernando Guerrero Rivera · Gerardo Salinas
Faculty Advisor(s)	· Dr. Yingchen Yang
Course Instructors	· Dr. Noe Vargas Hernandez · Mr. Greg Potter
College of Business and Entrepreneurship Collaboration	· Dr. Reto Felix (Instructor) · Annet Del Toro Villarreal · Hugo Gutierrez · AnaKaren Rios · Omar Rodriguez Perez · Mayra Varela

INDEX

DESIGN PROCESS

PROBLEM ID

PROBLEM FORMULATION

CONCEPTUAL DESIGN

EMBODIMENT DESIGN

TESTING AND VALIDATION

REFERENCES

IMPORTANT FILES

Back to the PROJECT MAIN PAGE.

DESIGN PROCESS

During Senior Design we followed a design process to make the Autonomous Underwater Vehicle be able to travel from point A to point B underwater using MRE (Marine Renewable Energy).

Problem ID

Problem Formulation

Conceptual Design

Embodiment Design

Testing and Validation

Back to INDEX.

PROBLEM ID

The objective of the Problem ID stage is to help the user identify what the problem to be solved is, as well as to brainstorm in order to figure out a way to solve the problem. The team thought not only about what our own take in order to solve the problem would be, but also the competitors that are already on the field and how can we differentiate our product from the competitors.

POG’S

There are many diverse types of renewable energies such as solar, thermal, wind, and hydropower energy. The team determined the best way to solve the problems is to utilize wave energy (hydropower). Essentially, wave energy is produced via the frictional force generated when the wind hits the surface of the ocean.  As it stands right now there is two methods of utilizing wave energy. One method is to utilize the energy supplied by the wave and converting it into electrical to power a battery housed in the system. The other method is for the propelling force to be direct from the wave via mechanical systems.

VOA

The following VOA chart(s) compare our proposed product to the closest(s) competitors: 

AUV (Autonomous Underwater Vehicle)	Team 8 G.B.J.F ENGINEERING
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency			•
Energy Efficiency			•
Communication System	•
Depth Rated		•
Minimal Impact on the Marine Ecosystem			•

COMPETITOR 1: SeaRaptor	TELEDYNE MARINE
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency	•
Energy Efficiency		•
Communication System			•
Depth Rated			•
Minimal Impact on the Marine Ecosystem		•

COMPETITOR 2: Comet-300	RTSYS
ATTRIBUTES	LOW	MED	HIGH
Cost efficiency	•
Energy Efficiency		•
Communication System			•
Depth Rated			•
Minimal Impact on the Marine Ecosystem		•

As you can see from the tables above, we determined our product will shine in cost efficiency and energy efficiency. Since our AUV will not need to be retracted to recharge resources will be saved there. Also, missions will be safer for those in charge of the AUV.

FINAL PROBLEM STATEMENT

While ocean robots have proven to be particularly useful in many applications they are limited by a crucial factor. Battery powered autonomous underwater vehicles are limited by the capacity of its battery. Due to this problem, they are limited to short term functions. As stated in the article a battery powered AUV is limited to “hours to days” and “tens to hundreds of kilometers. “[3] While the longevity and physical capacity is our focal point, it is not the only issue that would be resolved. A successful wave powered AUV would open a world of exploration for hydrographic surveyors, pipeline inspectors, and ocean observers.

Back to INDEX.

PROBLEM FORMULATION

The main objective of the problem formulation stage is to establish a clear problem. In order to do so we conducted extensive research on the following topics.

BACKGROUND RESEARCH

POWER SOURCES

AUV power sources can be broken down into three categories nuclear, combustion, and electrochemical. We will be focusing on electrochemical.

There are four different categories of electrochemical power sources.

· Pressure compensated batteries (batteries discharged at ambient pressure)

· Batteries discharged at atmospheric pressure

· Fuel Cells

· Seawater batteries

Note: Outgassing is the formation of gases during charging. Outgassing complicates charging and discharging. If a battery outgasses then the gases must be removed from the cells to prevent an explosive environment.

Chemistry	Energy Density (Whr/kg)	Life (Cycles)
Alkaline	140	1	Outgassing during high temp
Lead Acid	31.5	100	Outgassing
Silver Zinc	100	30	Outgassing
Ni Cad	33	100	Flat discharge curve
Ni MH	60	500	No outgassing
Li Ion	144	500	Limited by depth
Li Polymer	193	500	No outgassing

As it can be observed in the table above lithium polymer cells possess great energy density, low weight density, and long life. Furthermore, they do not outgas making recharging simpler.

Materials 

Materials suitable for underwater navigation need to have high strength-density ratio. Material such as metals have a tendency of corroding underwater. Chemicals present in sea water that led to corrosion are nitrates, acids, sodium, and other chlorides. The main question is what can be done to minimize these factors to minimize the problem of corrosion in sea-going vessels. The research was conducted by G.B.J.F. Engineering.

AUV Sensors

AUV's built-in sensors provide an abundance of valuable information, such as depth. AUV's can be equipped with still or video cameras, sonar, magnetometers, fluorometers and dissolved oxygen sensors. AUV's can communicate with each other via radio waves, but radio waves are not capable of navigating through water. AUV's utilize the last known GPS information and makes use of a built-in inertial navigation system. The function of the inertial navigation system is to document the vehicle's rotation, acceleration, and velocity. This function is also known as "dead reckoning" The profundity of the vehicle can be estimated using a sensor capable of measuring pressure. AUV's may have various underwater implementations. Commercial applications include observation of environment for oil and gas industry and searching for wrecks. Military applications include reconnaissance and anti-submarine warfare. It would also be innovative in the research department. A long-range H-ADCP is incorporated in the AUV's payload to measure wave flow tempo profiles. The profiles are used by the vehicle to institute path rectification to improve the vehicle's robustness. The mission is replicated when the vehicle arrives at the deduced wave field or when a necessity to renovate the deducing wave field is found. The wave fields created by the varying vortices supplies a rough estimate of the spatial wave administration, which is based on the turbulent field effects. The number, centers, and intensities of the vortices closest to the AUVs are determined from the H- ADCP profile. The AUV then can map the trajectory with the least amount of navigation time in the newly constructed sector. AUV's must be able to operate in ocean circumstances distinguished by complicated ocean circumstances. Unpredictability of the ocean can vigorously unsettle safety conditions and evolution of AUV missions. Forecasting and learning ocean currents is an especially important obligation to enlarge the AUV's safety when encountering unpredictability.

Communication

Communication underneath the water is based on acoustic waves. It can take up to 2 seconds to reach back and forth in a 1.5-kilometer distance. Communication can be affected by scattering, refraction and absorption through the water. Hollow waters and reef formation is where coordinated robotics can be most difficult to have communication in the ocean. It is also difficult to communicate with robots in hollow waters and reefs, which can be difficult for coordinated robotics. The communication will be completed at a very low bit rate. This is due to physical limitations which include delay and attenuation. Dolphins have given experts inspiration to carry information based on location and communication. Engineers came up with a tool named the "ultra-short baseline" (USBL) tool to help with the communication. The USBL tool is based on chirps, which will be used to communicate with the ship. The information will be sent in bytes and kilobits, in the form of a frequency signal. The idea comes from dolphins' use of singing and calls.

USBL is a type of acoustic reading that can tell you positioning. It does this by being an extension of a computer modem. Sound is transported from here towards the AUV which then replies with a new pulse. This rebound signal can be read by a computer located on the ship.

Coordinated Robotics is a project that is of great importance to pave the way for future underwater communication research. The company is working on such solutions to fasten delivery time and create bigger chances for opportunity.

COMPETITIVE PRODUCTS

Due to the high volume of competitors we narrowed down our research to 7 AUVs. Each of these AUVs represent a subsection sharing similar characteristics.  Below is more information pertaining to each of the 7 AUVs.  

1. TELEDYNE MARINE

Because this is a modern technology, there are few competitors. One of the main competitors is the company Teledyne Marine, which is one of the leading companies in the development of AUVs. Its main AUV is the SeaRaptor, which can travel from 3,000 to 6,000 meters deep. 

URL: http://www.teledynemarine.com/searaptor-auv?ProductLineID=15

COMPETITOR 1:     SeaRaptor	TELEDYNE MARINE
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency	•
Energy Efficiency		•
Communication System			•
Depth Rated			•
Minimal Impact on the Marine Ecosystem		•

2. RTSYS  

RTSYS is a company based in France. This company is specialized in underwater acoustics and robotics. RTSYS offers two varieties of AUVs which serve similar purposes. The Comet-300 AUV offers advanced navigation as well as a communication system capable of displaying navigation and position data in real time. 

URL: https://rtsys.eu/comet-300-auv

COMPETITOR 2:     Comet-300	RTSYS
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency		•
Energy Efficiency		•
Communication System		•
Depth Rated		•
Minimal Impact on the Marine Ecosystem		•

3. Monterey Bay Aquarium Research Institute

MBARI is an advanced center for ocean research and technology development located in Moss Landing, California. The development of their AUV, has the purpose of investigating important marine areas, which due to the lack of technology, have not been able to be investigated properly. 

URL: https://www.mbari.org/at-sea/vehicles/autonomous-underwater-vehicles/

COMPETITOR 3:     DORADO	MBARI
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency	•
Energy Efficiency			•
Communication System			•
Depth Rated			•
Minimal Impact on the Marine Ecosystem	•

4. Tiburon Subsea

Tiburon Subsea supplies renting and lease facilities for global underwater technology. To provide vendors of maritime facilities and businesses with the newest technology and assistance. Their focus is on autonomous underwater vehicles (AUV) and a broad affiliate network. Their engineering staff operates, trains and provides services to a multinational AUV fleet whose systems are fitted with payload packages including integrated benthos sonar systems, multi-beam, sonar side scans, magnetometers and sensors for bathymetry. 

COMPETITOR 4:     REMUS	Tiburon Subsea
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency		•
Energy Efficiency		•
Communication System		•
Depth Rated	•
Minimal Impact on the Marine Ecosystem			•

5. Phoenix International

Artemis, the Autonomous Underwater Vehicle of Phoenix International, is an compact deep-water search/survey system that functions with two field-swappable payloads. For effective single-pass data collection, the acoustic payload is a multi-beam echo sounder, a dual frequency side scan sonar, and a sub-bottom profiler that can be worked simultaneously. The optical payload is a high resolution payload that is (1936 x 1456 pixels) To build photomosaics of seafloor objects, the b&w camera was used. The geophysical payload is a 3-axis magnetometer, a 3-meter dipole electrical field (self-potential sensor), a CTD and a bathymetric and backscatter running multibeam echo sounder. Doppler Velocity Log, Ring Laser Gyro, and depth sensor combined with an Ultrashort Baseline onboard inertial navigation system (USBL) The system produces extremely precise, repeatable and accurate vehicle navigation and positioning. 

COMPETITOR 5:     Artemis	Pheonix International
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency		•
Energy Efficiency			•
Communication System			•
Depth Rated		•
Minimal Impact on the Marine Ecosystem		•

6. KONGSBERG

The ultimate in autonomous remote subsea survey capability is offered by KONGSBERG who provides the HUGIN Autonomous Underwater Vehicles - AUV / marine robot. The great maneuverability and high precision of stabilization characterize these free-swimming autonomous underwater vehicles. The ideal choices for these AUVs are hydrodynamic shape, precise instruments and outstanding battery capacity. 

COMPETITOR 6:     HUGIN	KONGSBERG
ATTRIBUTES	LOW	MED	HIGH
Cost Efficiency		•
Energy Efficiency		•
Communication System		•
Depth Rated		•
Minimal Impact on the Marine Ecosystem		•

USER RESEARCH

· AUV ́s AND THEIR MISSIONS AND APPLICATIONS 

An AUV can carry out a wide variety of activities. Analysis, industrial applications and surveillance applications are three major types. All these activities require human risk because they require risk-taking.

AUV is an important instrument for collecting samples for research studies. It is difficult for humans to do so largely because of the high hydrostatic pressure. AUV's are also used in detection, search and rescue, launch and recovery systems in the defense industries. AUVs are used in the marine sciences, marine chemistry, marine geology, interstitial water, marine biogeochemistry and underwater drilling platforms.

· AUV used in commercial applications 

AUVs can also help in prevention and correction of maintenance as well as inspection of activities. Underwater net opticfiber has been created for underwater communications. AUVs can be used to monitor and control underwater activities in the ocean. They can also be used for underwater telecommunications in real-time.

Certain research created for oil and telecommunication companies have been included in literature. An AUV “equipped with an auto tracker, sensors such as lateral search sonar, a geo positioner, shape recognizer based on neural networks, so via the simulation of algorithms of each module, incorporate into the physical part of the AUV.” [22] 

Hazardous underwater environments can be of great issue for not only access for humans, but also for the AUVs; AUVs can be trapped during missions. When exploring through solutions, a “C++ language can be implemented by estimating the error between the position of the AUV and element.” [22] Such examples include in pipelines or cable. 

· AUV used in surveillance applications 

Subaqueous conditions are unforeseeable because of frequent alterations of weather circumstances. There exists a very high chance that a military operation will not succeed.

The independence of Autonomous underwater vehicles are characterized by two factors: “amount of hours of operation necessary without occupying support and the capability to make crucial commitments to undergo a successful mission.” [22]  Obviously, the autonomy is a crucial feature in missions of surveillance, currently research has been executed. New architecture of controls are suggested to reach levels with characteristics of autonomy.

The autonomy of AUV ́s are represented by two aspects: number of hours of work without needing any assistance and the ability to made decisions to carry out a mission. The autonomy is an important feature in surveillance missions, “research has been carried out where new control architecture was proposed to meet the terms with aspects of autonomy referring to the decision making in the missions in which the AUV ́s initially lacks information.” [22] 

DESIGN SPECIFICATIONS 

The design of the AUV will be made taking in consideration the three distinct sections in which the team has divided the vehicle. The three sections that we have divided the vehicle are: 

· The Front Payload Bay 

· Power Take-Off Unit 

· Rear Payload Bay 

The reason why the team has decided to make this in the design of the AUV is because it helps the assembly process. The assembly process is and must be of extremely high importance since this could lead to imperfections throughout the model, and when talking about an underwater vehicle there is plenty of room for little mistakes to happen. Therefore, the team in ordinance with Dr. Yingchen Yang decided that creating this scheme will help avoid these tentative issues towards the near future. 

· The Front Payload Bay

Regarding the Front Payload Bay, the professor and advisor Dr. Yingchen Yang mentioned something particularly interesting that the team did not appreciate until it was commented with us, this is the fact that when the AUV will be in different water circumstances you will always want it to go down, even when we are not there to handle it ourselves. This made us think that since the front part of the AUV, similarly to any other type of underwater vehicle such as submarines, the first part or the part that leads when the vehicle will sink. [23] 

Therefore, the form of the AUV must have a certain weight that will help the overall body of the vehicle to sink even when there are storming conditions that might bring it up towards the surface. [23] 

· Power Take-Off Unit

In the Power Take – Off Unit section, the team will have to take in consideration for the design of the AUV that the main component present which will be the stator set, the battery pack, the magnets, as well as the translator assembly. The stator set will be the non-moving essential piece of the electric generator (also known as the motor) which will help in the energy flow process as the stator lets the energy navigate to the mechanical components of the AUV which will lead to its movement. [23] 

The battery pack will require to apply some necessary specifications, as that this will be the only method for which the AUV will be able to communicate and supply service due to no possible way of receiving any source of charge in the middle of the ocean. An important piece of advice that the team has acquired thanks to research throughout distinct AUV models is that Lithium-Ion batteries, seem to be some of the most reliable ways for us to store the energy the AUV will be able to generate. [23] 

An important aspect that we must cover to have a good battery in the AUV is the capacity of energy that it will be able to store. The capacity of the battery will depend on factors such as the mass of body, its components, and the surface of the AUV. The distance it can travel its directly proportional to the weight of it. The AUV's battery capacity will also depend on its mass and the temperature.

 Therefore, the team will try to find a suitable battery capacity once the overall weight of the AUV is known. Inside the Fron Payload Bay section, there will be the utilization of magnets to hold in place the battery pack and avoid the movement of the batteries, this will also help to hold up the section as a whole and provide enough magnetism for the battery pack installed. The AUV also counts with translators which will help with the task of calculate the instantaneous position of the vehicle in relation to the waves of the ocean, this will help the AUV to approach the waves to gain kinetic energy out of it.[23] 

An important piece of advice given to the team by Dr. Yingchen Yang, is that the AUV must have a certain weight to it, this will have to be acknowledged by the team when picking the different polymer materials, and the amounts of it that will be used in the production of the vehicle. The reason for the AUV needing to have a certain weight is that the team must make the vehicle as heavy as possible because this will be what will help it sink again if by any reason is thrown off by a wave, by an animal that could uplift it to the surface of the ocean, or by any outside effect. [23] 

However, the team should also make sure that it is not too heavy because if its weight happens to surpass a certain mark then it will sink to the bottom of the ocean, therefore a limit must be set regarding the weight of it. For us to properly give the AUV the weight we are looking for the team was advised to take in consideration the weight of the Battery pack as well as the included magnets, since these will be the ones responsible of the power generation for the vehicle, and this in addition with the translator assembly will be the effective for the team to manage the mass. [23] 

· Rear Payload Bay

Rear Payload Bay is composed of the propeller, the ballast tanks, and the control and instrument sensor. The propeller will be the necessary for the AUV to move from one place to another. If the propellers is affected or destroyed by some incident in the ocean then the vehicle will find itself stuck with little or no room to repair it.  

In order to avoid these issues, the propeller must be made from a durable material that can last for extended periods of time and will not damage. The damage the material might suffer depends on distinct aspects such as the temperatures under which it will be found, as well as the pressure that it will be under and the type of water that the AUV will navigate as the different pH these bodies of water might feature.[23] 

Another important part of the Rear Payload Bay will be the ballast tanks, which will be filled with water for navigational purposes. When the AUV is positioned in the surface level of the body of water, the ballast tanks will fill up with air. This means that the whole density of the vehicle will be significantly lower in comparison to the water, and it displaces. The AUV will have to dive back into the water, and during this process, a vent will be released and make the water in the surrounding of the AUV to dash inside.

Nonetheless, we must know that this is not the only function the ballast tanks have, since they can be filled up with not only water but with the amount desired of a gas in a compress form, this with the purpose of submerge and go back to the surface as the user desires. In this case the AUV will be able to back to the surface, through the use of compressed air which will be found in the ballast tanks though an air flask and this will propagate the water to get out by being pushed with a high pressure and at a high speed which will make it easy for the AUV to go back to the surface again.[23] 

The team has also intended in integrating a control and instrument sensor which will work in regard to different formations found across the path of the AUV. These sensors will be able to tell when possible damage sources appear along the way and help the vehicle avoid them. The ocean is difficult to predict in the sense that we are not able to know the different settings it will encounter, as well as the different animals that are under the sea and levels of water.  

Ø Housing of AUV

The housing of the AUV is one of the most important parts of the vehicle, this will protect and keep together the mechanism and since this will be under distinct circumstances, we need to produce a material that can be utilized in the different settings. [23]  An advice that Dr. Yingchen Yang gave to the team is to prioritize the housing of the AUV to remain in a void environment, this is especially necessary because having any sort of leak throughout the body of the AUV can cause the vehicle to sink and therefore stop working and would be a complete failure. [23] 

The housing of the AUV is intended of being constructed out of a non-magnetic material because if it is intended to be used for military purposes by the government, the team must use a material that will not result affected is an enemy tries to steal the AUV device by using magnetic devices. Also, because of the battery and the magnets used to hold the battery together we must use non-magnetic materials in order to not affect the environment of the power bank. [23] 

The material necessary to build a proper AUV housing must be made out of composite materials and/or metal alloys. The ideal material for the housing of the AUV, would be out a composite of titanium alloy. However, due to monetary constraints the team needs to figure out a more affordable and easier to obtain material. The team was able to notice the properties of this composite materials due to prior investigations made by IEEE Xplore.  

These composite materials are also extremely helpful for the AUV because of their light weight this feature, as mentioned above we need to have an essential weight to the AUV and having these lightweight materials to our advantage will help us have more chances of distributing the weight of the other components as we desire. [23] 

Another benefit of using this aluminum and titanium composite material alloy is that the AUV will feature a higher corrosion resistance across the housing, it is imperative that the corrosion resistance of the vehicle must be exceedingly high specially because it can go under unknown circumstances when it is used for exploration or for missions by the NAVY. This circumstances also require the freedom of changing the shape design of the vehicle depending on the mission or the reasoning behind it, and the aluminum alloy as well as titanium alloy give the chance to the user of changing the shape of the AUV as they desired, and it would be easier for the team to create a more specific shape depending on the requirements. [23] 

Back to INDEX.

CONCEPTUAL DESIGN

The objective of the Conceptual Design stage is to determine the equipment necessary for the assembly of the AUV. This while identifying what requirements does the AUV has to fulfill. After the analysis of the essential parts of the AUV, the team will identify how to integrate them in the system.

FUNCTIONAL DESIGN

MORPHOLOGICAL CHART

Sub Functions	Solution 1	Solution 2	Solution 3	Solution 4	Solution 5
Power Generation	Use Solar Energy By adding solar panels	Use Wind energy by adding a small wind turbine	Integrating an alternator system	Using waves to oscillate a spring system attached to a battery to charge	Use an internal combustion engine using biofuel
Accumulation of Power	Implement lithium batteries, known to be one of the longest lasting batteries in the market.	Implement alkaline batteries in high volume to withstand long distances.	Utilize a backup battery in case of emergency.	Lead Battery (Car Battery)	Vehicle 416mm Low-Voltage battery
Communication	Detection of large objects via use of a detection radar.	Implementation of a GPS system so operator always knows location	Implementation of heat sensors, in order to perceive any unrecognized activity underwater.	Use of night vision camera, in order to arrange missions during dark/deeper environments.	Typical Wifi band (2.4GHz)
Being able to be submersed underwater	Use steel to build AUV	Use polymers to build AUV	Use more sophisticated materials such as carbon fiber	Use Aluminum Alloys	Use Titanium
Military and Border Security Applications	Applying a small security camera with low capacity for recording.	Placing a GPS system, to find location of illegal activities.	Recognition of heat patterns, to locate recent activity.	Small device to dismantle mines for military protection.	Develop a UAV capable of storing an anti-submarine explosive device.
Data Collection	Applying a small tank for collection of water.	A small imaging system to capture images of the surroundings.	Sensor of pH balance in the different bodies of water, for research purposes.	Integrate valves on the surface, that can be controlled by the user to accumulate the samples required.	Collecting sand samples
Hydrodynamics	Shape 1	Shape 2	Shape 3	Shape 4
Sub Functions	Solution 6	Solution 7	Solution 8	Solution 9	Solution 10
Power Generation	Use a conventional high-performance electric motor.	Implement a new design in the AUV with the purpose of using ocean currents and generating electrical energy.	Use nuclear energy as the main source to power the AUV.	Implement an engine which runs on natural gas	Implementation of the principles of osmotic energy to generate electricity through salt water
Accumulation of Power	Vehicle 416mm High-Voltage battery	Vehicle 310mm Low-Voltage battery	Vehicle 310mm High-Voltage battery	Vehicle 260mm Low-Voltage battery	Vehicle 260mm High-Voltage battery
Communication	WLAN and Radio Communication	Acoustic modems	Frequency dependant attenuation	Satellite communications	Aerostat hotspot
Being able to be submersed underwater.	Use an anticorrosive coating on the material used in the manufacture of the AUV hull.	Implementation of anticorrosive paint on the hull and different components of the AUV exposed to salt water	Protection of materials exposed to saltwater using anti-corrosion cathodic protection.	Acrylonitrile Butadiene Styrene	Ni-base Corrosion Resistant Alloy
Military and Border Security Applications	Used for wreck inspection	Install a defense system capable of firing torpedoes against boats or mines.	Implementation of AUVs to check damaged ships after naval battles.	Radar capable of capturing electromagnetic waves generated by other ships.	Capable to deploy supplies to the army during war.
Data Collection	Equip the AUV with a small drill capable of drilling stone at the bottom of the sea.	Install a mechanical claw to obtain aquatic plant samples.	Equip AUV with a net designed to catch small species of fish.	Install a compartment to collect fossils.	Install a system able to collect sounds and frequencies coming from the bottom of the ocean.

CONCEPT VARIANTS AND SELECTION PROCESS

The team had to generate different concepts through CAD Software (Solidworks, NX) and after having multiple variations of the AUV design, the team proceeded to identify which AUVs designs would result to be more useful in the practice, as well as with the recommendations of the advisor.

	CV1	CV2	CV3	CV4	CV5	CV6	CV7
SF1	Wave energy with spring system 9,9	Alternator system7,10	Wave energy with spring system 9,9	Alternator system7,10	Wave energy with spring system 9,10	Alternator system7,10	Wave energy with spring sytem 9,9
SF2	Lithium batteries 7, 10,8,10	Alkaline 8,9,7,8	Lead 9,7,6,9	Lithium 7,10,8,10	Alkaline 8,9,7,8	Lithium 7,10,8,10	Lithium 7,10,8,10
SF3	GPS system 10	night vision camera 7	detection radar 7	GPS 10	GPS 10	Detection radar 7	detection radar 7
SF4	Alluminum Alloy 10, 10,10,10	Polymer 8,9,10,10	Titanium 7,10,7,7	Polymer 8,9,10,10	Alluminum Alloy 10,10,10,10	Titanium 7,10,7,7	Polymer 8,9,7,10
SF5	Small security camera 7	small security camara 7	GPS 10	small security camara 7	small security camara 7	GPS 10	GPS 10
SF6	Small tank storage 8	sand samples 9	small tank storage 8	sand sample 9	Sand samples 8	small tank storage 9	Small tank storage 9
SF7
FIRST ROUND	CV1	CV2	CV3	CV4	CV5	CV6	CV7
SKETCH
QUAL EVAL	SCORE (1-10)
Cost (SF1,SF2,SF4)	8.67	7.67	8.33	7.33	9	7	8
Durability (SF2,SF4)	10	9	8.5	9.5	9.5	10	9.5
Weight (SF1,SF2,SF4)	9	9	7.33	9.33	9	8.33	8
Power stored (SF2)	10	8	9	10	8	10	10
Portability (SF3, SF4, SF5, SF6)	8.75	8.25	8	9	8.75	8.25	9
TOTAL	46.42	41.92	41.16	45.16	44.25	43.58	44.5
CONCLUSION	In conclusion, this combination is very interesting. It combines such advantages as using the material aluminum alloy which is very durable against corrosion and lightweight. Lithium batteries are of the most durable options available. Also small camera and gps sensor would not impact the portability of the AUV much.	Disadvantages for CV2 include higher cost for night vision camera, and small security camera. Few advantages include durability and low weight for polymer. Overall, not considered.	When in comparison with other combinations, CV3 presents some disadvantages. These include heavier weight for material titanium, as well as for the lead battery used. Overall, CV3 not considered.	In summary, some advantages presented by CV4 include power stored from the lithium batteries, and lighter weight for alternator system, lithium batteries and the material polymer.	CV5 is very similar to CV4 in having strong durability from alkaline batteries and alluminum alloy material. It also posseses strengths in cost efficiency with spring system as well as allumnium alloy.	Major disadvantges for CV6 inlcude higher cost for alternator system, lithium batteries and the material titanium when in comparison with other materials. Overall, not considered.	Some advantages for CV7 include power stored from the lithium batteries. Other advantages include high durability from these lithium batteries as well as from the polymer material.
DECISION	CONSIDER		DNC	CONSIDER	?	DNC	?
SECOND ROUND	CV1	CV4	CV5	CV7
ROUGH CAD
QUAL-QUAN EVAL	VALUE (SCORE 1-10)
Weight	~32kg	~15kg	~55kg	~15kg
Cost	High (10)	Low (3)	High (10)	Medium (5)
Range/ Durability of Battery	High (10)	High (10)	Low (3)	High (10)
Charging Mode	High (10)	Low (3)	High (10)	High (10)
TOTAL	35
CONCLUSION	In summary, the strengths… the weaknesses…. And comments…
DECISION	CONSIDER	DNC	?

FINAL CONCEPT(S)

After a process of elimination, we arrived upon two final concepts. Model 1 uses a gyroscope method to harvest energy. Model 2 utilizes a mass spring damper system to harvest energy.

Figure 1: The present design consists of a system whose main characteristic is the implementation of a gyroscope. Theoretically, the gyroscope would move due to the movement of the waves. Correspondingly, the mechanical movement of the gyroscope would be transformed into electrical energy using a converter.

Figure 2: The second design implies the implementation of a system which when moving with the mechanical energy of the waves, the battery would generate an oscillatory movement which would generate the recharge of the batteries by means of other compounds. The electrical energy would be transmitted directly to the batteries.

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EMBODIMENT DESIGN

The objective of the Embodiment Design stage is to realize the concept previously designed.

STRATEGIES AND PRIORITIES

Starting from our final concept, we identified the necessary analysis and engineering work to realize the concept into a product.

TASK 1: DECIDING ENERGY HARVESTING METHOD

In order to decide between the gyroscope method or the mass spring damper system, we did a process of elimination. First, we analyzed a gyroscope method previously used by Nicholas Townsend from the University of Southampton.

Figure: An Illustration of the gyroscope system used in the model. [24]

Two studies in two different circumstances were done. One with high waves at a height of around .15m, the other with waves of around 0.1m. The power generated was then plotted and compared. [24]

Figure: Power Generated in both circumstances [24]

From the figure above it can be observed that even though the maximum generated power is promising, consistency is not there. As it can be seen there is moments were power is not even generated. A quick calculation of friction encountered during underwater travel was done to determine how much power is needed to overcome it. [24]

Power = ((½)*Iyy*Wf^2)/t, where (½)*Iyy*Wf^2 represents stored kinetic energy & t=time for flywheel to slow down from 5100 rpm to 0

Power = (0.5*0.00482*(5000*2pi/60)^2)/710 = 0.9W

From this calculation it can be observed that even at maximum power generated levels, which are rare, it takes almost 1/3 of the power generated to overcome friction. [24]

After these results it was determined to stop further developing this final concept. The efficiency of the gyroscope method was not appealing at all. [24]

TASK 2: CREATE A DESIGN SKETCH

The team created a design sketch of what the assembly should look like prior entering in the CAD design phase. This came alongside labeling the distinct parts that will be required with the purpose of starting to make our Purchas Approval Form.

Figure: Design Sketch

Figure: Part Labeling

TASK 3: CREATING A MORE DETAILED CAD OF OUR CHOSEN FINAL CONCEPT

After finally arriving on our final concept, we had to bring this concept to reality. Here is how we did it.

Figure: Detailed CAD model using NX12 software

TASK 4: DETERMINING HOW THICK THE HULL SHOULD BE

In order to determine how thick, the hull should be we conducted finite element analysis on the basic geometry of the hull. We did the FEA analysis twice changing the thickness every time. We started at a thickness of 0.5 inches, followed by 0.2inches. We applied the load by using the formula P = pgh +Patm. At a depth of 100m, to be conservative. Where the density is 1030 kg/m^3, gravity is 9.81 m/s^2, and pressure atmosphere is 101,325 Pascals. Therefore, the hydrostatic pressure applied is 1,111,856 Pascals.

FEA ANALYSIS WITH THICKNESS 0F 0.2 INCHES

Figure: Mesh created with a mesh size of 0.2 inches containing 12021 elements

Figure: Stress Analysis

Figure: Deformation Analysis

The hull suffered no deformation with a thickness of 0.2inches as it can be observed in the figure above.

FEA ANALYSIS WITH THICKNESS OF 0.5 INCHES

Figure: Stress Analysis

Figure: Deformation Analysis

Neither thickness suffered no deformation. Therefore, it was decided to move forward with a thickness of 0.2 inches in order to conserve mass and resources.

TASK 5: STABILIZING AUV

As the springs oscillate the mass, it is obvious that the AUV will not remain stable. Causing it to tip over. To combat this issue, it was determined that we must oscillate the mass in two parts. Each time keeping the mass oscillating on each side even. We will explain it using illustrations. Pay close attention to the center mass.

Figure : Stabilizing AUV

Figure: Stabilization of the AUV

Figure: Stabilization of the AUV

TASK 6: USE MEASUREMENTS FOR DEVELOPMENT OF EARLY 3D PROTOTYPES

After making the necessary design sketches, the appropriate 3D CAD designs, and acquiring the necessary measurements, the team proceeded to create its first 3D prototype. As we can appreciate the prototype its on early stages of development, but the assembly of the parts required results successful. This will help the team have a better point of view regarding how to proceed in the next task.

Figure: Overall view

Figure: Rear view

Figure: Top view

TASK 7: PREVENTING WATER FROM LEAKING ON AUV

Water leaks will be prevented using an O-ring. Rubber is used to make these bits. Two aluminum parts will be mounted on either end of the AUV using the appropriate screws, sealing the AUV and stopping water from entering. These components will be machined in accordance with the requirements.

TASK 8: CREATING A DAMPER

The oscillatory movement in the central mass is caused by the mechanical movement of the waves in combination with the stainless steel, causing the aluminum rods to go up and down like a piston. When this is combined with the aluminum chamber built to the design specifications, a damper is made. Air would be pushed into the chamber by the aluminum rod, causing resistance.

TASK 9: CONTROLLING THE DAMPING COEFFICIENT

We made the observation that the air pushed into the chamber may create an exaggerated damping coefficient resistance. Making it difficult for the springs to operate. In order to control this issue a hole will be drilled on each side of the chamber. Each hole will have an integrated release system for best optimization of the damping coefficient.

Figure: Release system

TASK 10: OPTIMIZING OSCILLATE PERFORMANCE

To optimize oscillate performance, different spring sets can be used on the design, allowing the best spring constant to be used based on the desired performance. Two disk springs are used to shield the parts and improve the bouncing movement.

MACHINING PROCESSES

Above we can appreciate the machining process for the parts of the AUV which use the following material: Ultra-Machinable 360 Brass, High-Strength 7075 Aluminum, and Polycarbonate.

The presented piece is an oscillating mass made of Ultra-Machinable 360 Brass. The oscillating mass is a central component of the AUV, and its function is to oscillate with the movement of the waves. It’s 0.375 ‘’ hole has a press fit with the damper rod, and a total length of 1.9’’.

The damper housing is made of high-strength 7075 aluminum, and its function is to work as a damper. The holes on this piece are meant to regulate the compressed air. The total length of this piece is 4’’ and a outside diameter of 2’’.

The following two pieces are components of added mass 1. These parts are made of Ultra-Machinable 360 Brass, with the main function to facilitate the oscillatory movement of the oscillatory mass. The total length of each of the pieces are 0.9’’ and a outside diameter and inner diameter of 1.25’’ and 0.85’’ respectively.

The four machined parts presents are made of Ultra-Machinable 360 Brass and are components of added mass 2. The purpose of creating both added masses is to find the perfect combination to improve the oscillatory movement of the center mass in a more efficient way. The length of each piece is 0.45’’ and an outside diameter and inner diameter of 1.25’’ and 0.85’’ respectively.

Shown above we can appreciate the blueprints for the distinct AUV parts that were machined through the Summer.

Above we can appreciate the finalized machined parts necessary for the assembly of the AUV. The parts machined included the following: Ultra-Machinable 360 Brass, High-Strength 7075 Aluminum, and Polycarbonate.

The following part is made of polycarbonate, and its function is to seal the AUV by connecting it against the damper housing. The outside diameter of the piece is 2’’, with an inside diameter of 1.3’’.

Presented above are the machined aluminum screws, which are going to be implemented as an escape valve in order to regulate the compressed air in the damper housing. There are 5 sets of screws, each set has a different center hole diameter in order to find the correct combination for a more efficient performance.

Shown above we can appreciate the machining process required for the Polycarbonate, creating the end caps necessary for the AUV.

Above we can appreciate the fit testing process of the AUV caps, as well as the fit and placement of the O-rings before proceeding with the application of the adhesive cement.

One of the challenges faced while practicing the application of the adhesive cement was that if this process was not done properly and did not cover the entire surface, as well as if it was not given the proper time to dry this could lead into it breaking the piece and detaching from the surface when force was applied towards it.

Items used for fixing the polycarbonate ends.

The process of testing how the adhesive cement works was done in order to prevent any mistakes at the actual time of applying it to our finalized AUV model, and that is shown above. We can also appreciate the final application of the adhesive cement to the AUV model, with the purpose of achieving a snugger fit.

In the images shown above we can find a visual representation of the AUV model, which demonstrate the assembly process.

Mount and Connector Footprints

In the image shown below we can see the footprint for the mount piece. This mount piece has been decided to be made of 6061 Aluminum.

In the image shown below we can see the footprint for the connector piece. This mount piece has been decided to be made of 6061 Aluminum.

AUV Camera Mount

Team installed a Camera system to observe movement of the oscillatory mass inside the AUV. Currently camera is mounted to a fixed beam. In the future team will have to mount camera to a moving beam so AUV can be observed as it moves about the x,y,z plane.

Assembly Challenges

A challenge the team is facing is that after assembling the AUV caps and tightening them up, the mass does not move as expected. As you can appreciate in the images above, to solve this issue the team loosen up the screws in the AUV and this are the results we obtained. As you can observe the mass does move but not very smoothly, and we are afraid this can cause some leakage to happen too.

After showing results to Dr. Yang, we understood that loosening up is just the first step. The team needs to fasten the screws again. But we must fasten them correctly to achieve a good alignment for a smooth oscillation. We will have to try it over and over again in different ways to fasten them until we achieve the expected performance.

In the video shown above, we tried to troubleshoot for the reasoning behind why the rod does not run as smoothly as expected. The latest hypothesis is that as we can see in the image one end of the rod was not filed correctly. In the first part of the video, we see the side of the rod that was filed all the way through, and it slides smoothly when compared to the second part of the video where when testing the other side of the rod we can see the opposite.

ANALYSIS

The team in association with Dr. Yang decided that it was better to concentrate in the damper mechanism for this project, for which reason we will not be able to collect the data of how much energy it generates, instead will concentrate in the theory side of the project. The team would consider the mechanism to work properly if the energy generated by the waves shows the damper mechanism to work as expect by creating a transversal movement that should generate the power necessary.

Simulation

As part of the simulation process, the team has planned to use Dr. Yang’s water tank at the Machine Shop located in the Brownsville campus. The water tank will provide a similar environment as the one that we are seeking to use the AUV at, since it provides artificially generated waves that will help us show how the damper turns the kinetic energy into power. This mechanism has proved to properly function when assembling in NX 12, but we will ensure that this is possible through multiple tests in the water tank once the assembly of the AUV concludes.

FMEA: Failure Modes and Effects Analysis

FAILURE MODE AND EFFECTS ANALYSIS

Item:

AUV

Responsibility:

Team 8

FMEA number:

N/A

Model:

Model 1

Prepared by:

Team 8

Page :

N/A

Core Team:

SDII

FMEA Date (Orig):

9/16/2021

Rev:

1

Process Function

Potential Failure Mode

Potential Effect(s) of Failure

Sev

Potential Cause(s)/ Mechanism(s) of Failure

Occur

Current Process Controls

Detec

RPN

Recommended Action(s)

Responsibility and Target Completion Date

Action Results

Actions Taken

Sev

Occ

Det

RPN

Housing of AUV

Leakage

The vehicle will sink and therefore stop working.

10

If the housing gets damaged while shipping or in the assembly processes.

6

Assemble an O-ring, made out of rubber. Two aluminum parts will be mounted on either end of the AUV using the appropriate screws, sealing the AUV and stopping water from entering.

8

480

The assembly of the O-ring, as well as to use safety methods of shipping to the user in order for it to arrive without any damage that can lead to leakage.

Assembly Engineer / Shipping Method

Use of High-Strength 7075 Aluminum Rod to avoid easily get damaged

8

6

8

384

Magnets to hold battery in place

Demagnetize the magnet, making the battery to lose its place and stop the process of storing energy.

Leave the AUV out of power, which can result in it to get lost depending where it is at the moment.

9

If it gets close to a strong magnetic field of opposite polarity the magnets inside can be demagnetize.

4

Give a proper instruction manual, specifying the possible effects of not storing it properly. Also, provide a special case that can neglect outside magnetic fields from affecting the magnets.

8

288

Providing the user with an special carrying case that avoids external magnetic fields of opposite polarity.

Design Engineer

Development of a detailed instruction manual in order to avoid these issues. As well as to seek materials that can be used as isolating materials in the carrying case the AUV requires.

8

4

8

256

QFD (Quality Function Deployment)

QFD is a mechanism to ensure that the customer needs drive the entire product design and production process in the company, including market planning, product design and engineering, process development and prototype evaluation, as well as production, sales, and service.

Customer Quality Experience	Design Spec	Critical Function(s)	Component(s)
Reliable method for transportation of material underwater.	Possibility of creating a cavity to serve as storage for research material.	Need to find a way in which at the time of storing the material we will not let any leakage enter the system.	Storing space inside AUV housing.
Have an unlimited source of energy, while at the same time not running out of power.	Create a renewable source of energy via a damper mechanism, which will provide energy through the kinetic energy obtained with the motion of the waves.	The damper mechanism is custom made by the team, therefore if we plan to make multiple, we need to make sure all the measurements are the same because if not this can lead it to not work properly.	Custom damper mechanism assembled by team.
Capable of reaching underwater ground levels, which for people it is hard to achieve due to high pressures.	Made a design that makes use of O-rings in the extremes of the AUV in order to avoid any type of leak due to the high pressure.	Need to verify that the O-rings fit the caps properly on both sides of the AUV.	O-rings.

Potential Customers

Early on the following AUVs were designated as competitors, however we then identified them as potential customers due to their limitations when recharging. All of these AUVs take up resources by having to be retracted from their mission to be charged. Our design would improve all of them.

1. Teledyne Marine

2. RTSYS

3. Tiburon Subsea

4. Kongsberg

Hands on Analysis

This video illustrates the oscillation of the mass when subjected to the following parameters: Gear pulse: 6, set point: -7000 to 7000, Velocity: 180 rpm. All tests were done with the AUV inclined at an angle of 75 degrees to ease the movement of the mass. The ruler is in cm.

This video illustrates the oscillation of the mass when subjected to the following parameters: Gear pulse: 6, set point: -7000 to 7000, Velocity: 250 rpm. All tests were done with the AUV inclined at an angle of 75 degrees to ease the movement of the mass. The ruler is in cm.

This video illustrates the oscillation of the mass when subjected to the following parameters: gear pulse: 6, set point: -7000 to 7000, velocity: 300 rpm. All tests were done with the AUV inclined at an angle of 75 degrees to ease the movement of the mass. The ruler is in cm.

A different view of how the whole system works. In this video the AUV was subjected to the following parameters: Velocity: 180, Gear pulse: 6, set point 7,000, also in this view you can observe how the integrated camera system functions to give a better observation of the mass. Behind it you can also see the motor setup. Giving a better feel of how the overall system is working.

A different view of how the whole system works. In this video the AUV was subjected to the following parameters: Velocity: 250, Gear pulse: 6, set point 7,000, also in this view you can observe how the integrated camera system functions to give a better observation of the mass. Behind it you can also see the motor setup. Giving a better feel of how the overall system is working.

A different view of how the whole system works. In this video the AUV was subjected to the following parameters: Velocity: 360, gear pulse: 6, set point: 7,000, also in this view you can observe how the integrated camera system functions to give a better observation of the mass. Behind it you can also see the motor setup. Giving a better feel of how the overall system is working.

The graph above illustrates the behavior of the oscillating mass when subjected to conditions of velocity: 180 rpm, gear palse: 6, setpoint: -7000 to 7000. After plotting the graph, we determined the slope, which is the avg velocity. After obtaining the velocity we determined the power by using the following formula. Power = damping coefficient * velocity

The graph above illustrates the behavior of the oscillating mass when subjected to conditions of velocity: 250 rpm, gear palse: 6, setpoint: -7000 to 7000. After plotting the graph, we determined the slope, which is the avg velocity. After obtaining the velocity we determined the power by using the following formula. Power = damping coefficient * velocity

The graph above illustrates the behavior of the oscillating mass when subjected to conditions of velocity: 300 rpm, gear palse: 6, setpoint: -7000 to 7000. After plotting the graph, we determined the slope, which is the avg velocity. After obtaining the velocity we determined the power by using the following formula. Power = damping coefficient * velocity

Power and Time Plots for Reduced Model

Parameters used:

Gravitational acceleration, g = 9.81 m/;

Wave frequency, = 1 Hz;

Wave height, H = 0.2 m;

AUV oscillation amplitude, theta = pi/3;

Phase angle, phi = 0;

Power take-off (PTO) mass, m = 0.357 Kg;

PTO mass stroke, z0 = 0.038 m;

Disk spring parameter, n = 100;

Absorbed power, P = 0.3215 W

Absorbed power, P = 0.3201 W

Absorbed power, P = 0.3205 W

Absorbed power, P = 0.2097 W

Absorbed power, P = 0.1115 W

Absorbed power, P = 0.2775 W

Ns/m

Absorbed power, P = 0.1629 W

As you can see there is a deviation between the experimental and mathematical model results. We believe the reason for this is the quality of the camera. Due to budget issues, we utilized a provided camera not equipped with the frame rate technology to analyze every 0.1 second. Either that or the video viewing software we used did not support its capabilities. This is something to keep in mind in the future when other senior design groups continue this work.

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TESTING AND VALIDATION

The objective of the Testing and Validation stage is to prove our theories and methodologies in order to see if they work as intended, as well as to make the necessary adjustments in order to achieve the most efficient AUV results. This stage of the project Is currently a work in progress.

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REFERENCES

1. “Autonomous Underwater Vehicle (AUV) Market,” Market Research Firm. [Online]. Available: https://www.marketsandmarkets.com/Market-Reports/autonomous-underwater-vehicles-market-141855626.html. [Accessed: 28-Jan-2021].

2. “Autonomous Underwater Vehicle Manufacturers (AUV, UUV, ROV),” Unmanned Systems Technology. [Online]. Available: https://www.unmannedsystemstechnology.com/category/supplier-directory/platforms/uuv-manufacturers/. [Accessed: 28-Jan-2021].

3. “Autonomous underwater vehicles,” MBARI, 23-May-2018. [Online]. Available: https://www.mbari.org/at-sea/vehicles/autonomous-underwater-vehicles/. [Accessed: 28-Jan-2021].

4. “Comet-300 AUV,” RTSYS, 13-Jan-2021. [Online]. Available: https://rtsys.eu/comet-300-auv. [Accessed: 28-Jan-2021].

5. “SEARAPTOR AUV,” ProductPage. [Online]. Available: http://www.teledynemarine.com/searaptor-auv?ProductLineID=15. [Accessed: 28-Jan-2021].

6. T. Baoqiang and J. Yu, “Current status and prospects of marine renewable energy applied in ocean robots,” International Journal of Energy Research, vol. 43, no. 6, pp. 2016–2031, Jan. 2019.

7. Bellingham, J. (2009). Platforms: Autonomous underwater vehicles. Encyclopedia of Ocean Sciences, 159-169. doi:10.1016/b978-0-12-813081-0.00730-8

8. http://web.mit.edu/12.000/www/m2005/a2/finalwebsite/equipment/robotics/structure.shtml

9. A. M. Bradley, M. D. Feezor, H. Singh, and F. Y. Sorrell, “Power Systems for Autonomous Underwater Vehiclesa,” IEEE JOURNAL OF OCEANIC ENGINEERING, vol. 26, no. 4, pp. 526–536, Oct. 2001.

10. Author Logan Mock-Bunting. (2015, November 25). The many challenges of underwater communication. Retrieved February 25, 2021, from https://schmidtocean.org/cruise-log-post/the-many-challenges-of-underwater-communication/

11. Mange, V., Shah, P., & Kothari, V. (2019, June). Autonomous underwater vehicle: Electronics and software ... Retrieved February 25, 2021, from https://www.irjet.net/archives/V6/i6/IRJET-V6I6689.pdf

12. Ewachiw, M. A., Jr. (2014, June). Design of an autonomous underwater vehicle (auv) charging ... Retrieved February 25, 2021, from https://apps.dtic.mil/dtic/tr/fulltext/u2/a610285.pdf

13. ROV FAQs. (2021, January 28). Retrieved February 25, 2021, from https://schmidtocean.org/education/rov-faqs/

14. Ashish. “How Does A Submarine Dive, Resurface And Navigate Underwater? " Science ABC.” Science ABC, 3 Dec. 2019, www.scienceabc.com/innovation/how-does-a-submarine-dive-resurface-and-navigate-underwater.html.

15. Hyakudome, Tadahiro. “Design of Autonomous Underwater Vehicle - Tadahiro Hyakudome, 2011.” SAGE Journals, journals.sagepub.com/doi/10.5772/10536.

16. Yun Hae Kim, Young Dae Jo, Sung Youl Bae and Seok Jin Sin, "Material design of Al/CFRP hybrid composites for the hull of autonomous underwater vehicle," OCEANS'10 IEEE SYDNEY, Sydney, NSW, Australia, 2010, pp. 1-5, doi: 10.1109/OCEANSSYD.2010.5603587.

17. Structure. [Online]. Available: http://web.mit.edu/12.000/www/m2005/a2/finalwebsite/equipment/robotics/structure.shtml. [Accessed: 09-Mar-2021].

18. E. Delory and J. Pearlman, Eds., “Chapter 5 - Innovative Sensor Carriers for Cost-Effective Global Ocean Sampling,” in Challenges and Innovations in Ocean In Situ Sensors, Elsevier, pp. 173–288.

19. Author Logan Mock-Bunting, “The Many Challenges of Underwater Communication,” Schmidt Ocean Institute, 25-Nov-2015. [Online]. Available: https://schmidtocean.org/cruise-log-post/the-many-challenges-of-underwater-communication/. [Accessed: 09-Mar-2021].

20. “AUV LAB – ODYSSEY CLASS HISTORY,” MIT Sea Grant. [Online]. Available: https://seagrant.mit.edu/auv-odyssey-class/. [Accessed: 09-Mar-2021].

21. “Is Lithium-ion the Ideal Battery?,” Advantages & Limitations of the Lithium-ion Battery - Battery University. [Online]. Available: https://batteryuniversity.com/learn/archive/is_lithium_ion_the_ideal_battery. [Accessed: 09-Mar-2021].

22. F. Aguirre, S. Vargas, D. Valdes, and J. Tornero, “State of the Art of Parameters for Mechanical Design of an Autonomous Underwater Vehicle,” International Journal of Oceans and Oceanography , vol. 11, no. 1, pp. 89–103, 2017.

23. Yang, Y., 2021, ‘Weekly Faculty Advisor Meetings’

24. N. Townsend, “In situ results from a new energy scavenging system for an autonomous underwater vehicle,” OCEANS 2016 MTS/IEEE Monterey, 2016.

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IMPORTANT FILES

This is a summary of important Senior Design files, click on each to open in a different window.

SDI

REVIEWS

R1

R2

RN

MIDTERM

PRESENTATION

FINAL

PRESENTATION

REPORT

SDII

REVIEWS

R1

R2

RN

MIDTERM

PRESENTATION

FINAL

THIS WEBSITE

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