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Titan UAV – Project Operational Reconnaisance Canvassing Aircraft (ORCA) Abstract When the 2013 Titan UAV Team made the decision to create a UAS for the AUVSI student competition, the decision was an ambitious one. California State University of Fullerton—unknown in aviation, lacking an aerospace California State University, Fullerton Mechanical Engineering Department

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Titan UAV – Project Operational Reconnaisance Canvassing Aircraft (ORCA)

Abstract

When the 2013 Titan UAV Team made the decision to create a UAS for the AUVSI student competition, the decision was an ambitious one. California State University of Fullerton—unknown in aviation, lacking an aerospace

California State University, Fullerton

Mechanical Engineering Department

program or even courses in systems engineering—had previously offered FSAE as a way for students to distinguish themselves at a competition where, presumably employers would be on hand to accept resumes and discuss jobs.

The goal behind the formation of the 2013 Titan UAV Team was threefold: to create an unmanned aerial system and compete at PAX River in the AUVSI student competition; to personally challenge ourselves in our ability to learn, understand, design and manufacture a product in less than a year; and to create department awareness and lay a strong foundation for a platform on which future UAV teams might build on.

CSUN (California State University Northridge), CSUF’s sister school, had competed for several years and in the past done quite well. They graciously allowed the Titan UAV Team to tour their program and examine its workings first hand. They also pointed out that, while many of the participants were mechanical engineers, the challenged posed by the competition was primarily one of systems engineering—was it possible to make a fully autonomous system from a systems engineering approach which would operate according to mission parameters, and do it safely.

The Titan UAV Team is: Dianna Jones, Team Leader and Systems Engineer; Chris Roper, Structure Team Leader; Michael Stragier, Structure Team, fuselage/empennage design; Alvaro Solano, Structure Team, airfoil design; Jake Bailey, Payload Team Leader; and Robert Alatorre, Payload Team, vision systems design.

The project name for the 2013 Titan UAV Team was Project ORCA: Operational Reconnaissance and Canvassing Aircraft. It is a high-wing, twin propeller aircraft constructed of fiberglass and ABS plastic, with dual-redundant power, isolated actuator, microprocessor-in-series control flight system capable of autonomous or manual pilot intervention. The autopilot used is the ARDUPilot Mega (APM). The camera used is a Go-Pro Hero 2 for its long distance and high-definition capabilities which work well with the custom ORCAVision target identification software.

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Table of ContentsAbstract...........................................................................................................1

Systems Engineering Approach.................................................................................3

Mission Requirements and Analysis........................................................................5

Expected Performance.........................................................................................5

Description of the UAS Design.................................................................................5

Design Description: Air Vehicle.............................................................................5

Design Description: Ground Control Station..............................................................8

Design Description: Payload.................................................................................8

Mission Planning...............................................................................................8

Data Processing.................................................................................................8

Method of Autonomy..........................................................................................8

Target Types Supported by Autonomous Cueing.........................................................8

Test & Evaluation Results........................................................................................9

Iron Bird Tests...............................................................................................9

Structure Tests............................................................................................10

Flight Tests..................................................................................................11

Safety Considerations and Approach........................................................................11

Quality Control/Risk Management.....................................................................11

Safety Features...........................................................................................12

Fail-Safe Design Concept................................................................................12

References........................................................................................................13

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Systems Engineering ApproachThe primary objective of Project ORCA was to deliver a fully-functioning Unmanned Aerial System based on apurposeful, well-thought out design from start to finish. In order to accomplish this goal, a thorough grasp ofsystems engineering concepts was required. As was previously mentioned in competition documentation, and iscopiously documented by past team journal papers, the problem of the competition is primarily one of systemsengineering—anyone can purchase a model airplane off the shelf, an expensive autopilot, and put them together. Butcan a team engineer a structure and create a functioning electronics platform, do it according to systems engineeringstandards, and do it safely and well? That is the main objective behind the California State Fullerton entry into the2013 AUVSI student competition.

The systems model utilized by the 2013 Titan UAV Team was taken from the NASA Systems EngineeringHandbook [1.]. The systems engineering approach emphasizes planning and identification in lieu of design andredesign and on-the-fly fixes when initial and successive designs prove unsuccessful. The first step in this processwas to identify the primary stakeholders—defined as “a group or individual who is affected by or in some wayaccountable for the outcome of an undertaking” [1.]—to our three-part goal: these groups are members of the TitanUAV Team, the AUVSI competition judges, and future CSUF UAV teams.

Next, it was important for each team member to become familiar with the competition objectives, as documented inthe competition Statement of Work (SOW) [2.]. Requirements statements were drafted based on the key systemrequirements taken from the SOW. The objectives were then boiled down to the most basic level—essentiallybuilding block requirements. The derived requirements were then placed into a Requirements Verification Matrix(RVM), along with the method of verification, the team responsible for the requirement, the date of expectedverification, date of actual verification, and any notes regarding the success or failure of verifying. See Figure 1 foran excerpt of the RVM.

Figure 1: Requirements Verification Matrix (RVM) Excerpt

Once the requirements were understood and mapped, the teams conducted an extensive literature review in order toevaluate the most efficient method by which to fulfill the mission requirements. Payload and Structure Teamsproposed preliminary design concepts and weighed alternatives based on effectiveness, cost, and time constraints.During this stage, the basic required structure emerged, after conducting detailed analyses on different designsolutions.

As team members began to construct the preliminary project design, more requirements were assessed and addedinto the RVM based on feedback from both structure and payload teams. At the conclusion of this, teams conducteda preliminary design review (PDR) armed with an RVM containing derived SOW requirements, structure flowdownrequirements, and payload/autopilot flowdown requirements. It is important to note that requirements identificationwas an iterative process.

After a preliminary design was agreed upon, a logical decomposition model was constructed (see Fig. 2), at whichstage integration points would become to be easily identifiable. It was at these key process points that teams wererequired to be mindful of possible integration issues, to ask themselves “what could go wrong?”, and to proceed insuch a way as to mitigate the risk of failure.

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At this point in the design process, the concept of Failsafe was introduced. This is discussed in later sections, but itis important to note that the Failsafe concept was built into the project from the preliminary design, as is evidencedby some of the design decisions which were made.

Figure 2: Logical Decomposition Structure

After the PDR, individual teams went to work fleshing out the details of their systems. At this point, a RiskManagement Plan was developed (See Safety Considerations and Approach), as well as a detailed budget,Milestones, and a detailed team schedule.

Table 1: Project ORCA Milestones

Team members then created a fully-detailed design solution based on the decisions made at the PDR. Conceptualmodel and materials review were completed, followed by a detailed subsystems design review. Once all subsystems

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were approved by the team, a critical design review was conducted with emphasis on integration needs. After anypotential integration issues were addressed, the final design was approved and the team moved to manufacture.

Mission Requirements and AnalysisThroughout the lifecycle of the project, mission requirements have been at the forefront of all planning, design,manufacture, integration, and test. As mentioned in the previous section, one of the first and most critical actions inthe process was to create the Requirements Verification Matrix, which governed how the team proceeded insubsequent phases of the program lifecycle.

Expected PerformanceProject ORCA has undergone significant test and verification. Every component used in the project has been inspected and validated according to standards set forth in the Project ORCA Quality Manual (See section on Quality Control). The Titan UAV Team is optimistic about the system’s ability to autonomously navigate waypoints, make in-flight adjustments, and perform autonomous landing.

The team is most proud of the custom vision software designed specifically for competition target identification, andexpect it to make a good showing at the 2013 AUVSI student competition. The goal the vision architect has worked toward from initial concept is auto-identification of all six required characteristics for each target.

Description of the UAS Design

Design Description: Air Vehicle

Fuselage/EmpennageWhen designing an airplane for a competition such as the one described above, it’s obviously desirable to designtowards ensuring mission success. It was decided that the best way to ensure mission success was to incorporateredundancy and safety into the design. What this specifically meant for the structure team was to follow the designof a proven system and apply it to this particular application. The other constraint that was a driving factor for manyof the decisions made was that of cost. To lower the cost, while at the same time design for reliability the teamdecided to explore various layouts of airplanes and weigh their benefits, putting an emphasis on manufacturability,safety and cost. To assist with this task, a design process involving various morphological charts, Pugh charts, andbasic literature surveys led us to make the basic decisions outlined below.

Table 2: Project ORCA Design Decisions

Topic Decision

Construction TypeConventional tube, wing and tail

Wing Placement High WingWing Shape RectangularTail Style T-Tail

Motor ArrangementDual motor, under-wing mounted

Landing Gear Style Quad arrangement

FuselageThe fuselage is the spine of the system; it acts as the glue holding all of the aerodynamic components together whileproviding a structure to house the payload. If the airplane is not of a blended wing style construction, the fuselage

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will have little aerodynamic benefit. In fact, fuselages will induce mostly negative effects. This fact requires thedesigner to be conscious about what shape to use to house the necessary components, while at the same timeminimizing negative effects.

The basic idea behind fuselage design is to reduce the overall volume of material as much as possible while notcompromising safety. To do this, it is necessary to work with the payload designer to determine basic dimensionsneeded and choose a solution that will make for smooth integration.

SummaryThe following is a list of constraints supplied by the payload team or derived from the competition (see RVM) thataffect the design of the parts in question.

Dimensions:

Overall length shall not exceed: 48 inches Payload height: 4 inches Payload length: 18.5 inches Payload width: 4 inches

Other Flowdown Requirements:

The fuselage shall be a tube type shape with a tapered trailing edge going all the way to the tail The nose shall be spherical but other configurations should be explored and tested There shall be a mounting spot for the wings at the top of the fuselage but cut away to promote

streamlining The fuselage shall accommodate space for the camera on the belly of the plane, towards the nose and clear

of the landing gear The fuselage shall accommodate a mount for landing gear. The vertical stabilizer shall house an antenna for transmitting and receiving

The diameter of the tube for the fuselage is based off ofthe requirement given by the payload. The frontal areahousing the payload consists of a rectangular shape withrounded edges. This shape was chosen to incorporatestreamlining and it has the least amount of area whilestill successfully enclosing the entire payload. Figurefour below illustrates the shape used, which is based offof an equation driven curve.

As shown above the boom is streamlined in a feasiblemanner, closely following the shapes presented in figureone above as best as possible.

The location of the mounting surfaces for the wingsdepends on the center of gravity of all of the parts fromthe payload as well as the effect of the motors beingmounted on the wings.

EmpennageThe empennage was constructed in a "T-tail"configuration. It is called “T-tail” because the horizontalstabilizer is positioned on top of the vertical stabilizer.

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Figure 3: Fuselage Design Detail

This is to ensure that the tail is clear of the wash from the body allowing it to be more effective. As stated before, T-tails exhibit 90% efficiency.

The Aspect Ratio of this surface shall be equal to 4.5. This results in the span being 28 inches long and having achord length of 6.25. The airfoil shape will be the Eppler E168, following the recommendations from above andbecause there exists substantial amounts of data for it. The vertical stabilizer will have a constant chord up until acertain point and from there sweep back to the tip. The base chord is 7 inches whereas the tip chord will measure 4inches in length. The vertical stabilizer will span 7 inches.

WingIn the preliminary stages, airframe considerations were leaning towards the implementation of a flying wing design.They are the most aerodynamically efficient flying vessel because they contain no fuselage and tail, which areresponsible for a lot of the parasitic drag while in flight. There is also a big weight reduction from theimplementation of this design. Through our literary review we came to several conclusions that made us turn awayfrom this type of design. Due to the lack of stabilizing surfaces these types of airframes are considered to be veryunstable. The goal of the project is to have the most stable airframe possible in order to achieve mission success. Thecompetition does not judge on how an aircraft looks or on how it flies. Instead, it judges how well the aircraftcompletes the mission goals. This relies heavily on the airframe stability. Therefore, after consulting the RVM, otheroptions were considered.

Through the use of a Pugh Chart, we examined the RVM and ranked different airframes. From this Pugh Chart, we determined that a twin-propeller aircraft was the best choice as far as stability and achieving mission requirements. In order to mount the propeller motors onto the wing itself, we needed a high wing design. The high wing design provides several advantages that can be used for mission completion. As mentioned before, there is enough clearance below the wings so that the motor mount can be attached with enough room for the propeller

to spin adequately. Another reason that the high wing design is effective is that it incorporates an inherent dihedral effect without the use of an actual dihedral. This allows for stability along the roll axis since the center of gravity is located below the wing. The structure acts like a pendulum and levels itself from a bank position.

One of the most important parameters to choose as far as wing design is concerned is the choice of the airfoil. Theshape of the airfoil determines lift and drag characteristics of the wing. Through the literary review, it wasdetermined that the Clark-Y wing is the most beneficial to complete the mission. Pictured below is the Clark-Yairfoil shape used.

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Figure 4: Pugh Chart Used in Airframe Considerations

Figure 5: Example of a Clark-Y Airfoil Shape

The Clark-Y is beneficial to our mission because it has good lift and drag characteristics at low to medium Reynoldsnumbers, which is the range that our airframe will be performing under. The Clark-Y is a very well recognizedairfoil and is used in many model aircraft. The foam chosen was made of expanded polystyrene. This foam waschosen due to its high strength and its vacuum bagging capabilities. The way that this airfoil is shaped allows for athick enough carbon fiber spar run through the wing to provide structural rigidity. It has a deep mid-section whichallows for a thick enough spar to run servo/motor cables through. The bottom part of the Clark-Y airfoil is also nearhorizontal, which allows us to place the motor mount under the wing. The mount will be placed under the fiberglassthat will be laid over the foam wing. The fiberglass will provide additional reinforcement for the wing structure.Several schedules were tested out and compared in terms of strength and weight. After many different attempts, 2fiberglass sheets at a 45 degree angle were chosen. This schedule provided the strength necessary at the lowestweight.

One of the biggest factors that come into our design is the manufacturing complexity. Designing and manufacturingwings can get very complex when adding parameters like taper and sweep. Since our mission does not specificallyrequire any of these types of designs, we decided to keep it as simple as possible. This meant going with a constantchord rectangular wing. Rectangular wings have adequate aileron effectiveness and are very stable. These types ofwings are favored when considering low cost/low speed airplanes. The airframe will be flying at a cruise speed of

about 30 miles per hour, so a rectangular wing would be ideal. The manufacturing costs will also be kept low

because rectangular wings are not as complex. The wing was chosen to have a wing span of 6 feet with a chord

length of 1 foot. This gives us an aspect ratio of 6 , which gives low induced drag and a high lift coefficient.

The wing loading using these parameters was determined to be 18.48

oz

ft2 . This wing loading is acceptable for a

trainer type plane requiring stable flight.

MotorOnce the flight characteristics of the aircraft were obtained, it was then possible for to determine the style of motorand propeller configuration.

It was determined based on the established theory that a permanent magnet, out runner style brushless motor of arelatively low rpm per volt rating would be best to provide a sufficient amount of torque to the chosen propeller.Next it was decided that the propeller should be of a relatively large diameter with a low pitch in order to maximizethe advantage provided by the high torque motor. Then in order to determine that the configuration chosen wouldprovide the correct amount of flight time and in order to confirm that the power supply chosen would provide powerfor the desired length of time a many simulations needed to be run to optimize the design; in order to do this aprogram called MotoCalc was used to provide the necessary data.

Design Choices:

Motor: Great Planes GPMG4700 – RimFire .32 42-50-800 kV

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Propeller: 14 x 8 composite, NASA airfoil Power Supply: Max Amps 11.1V 3S LiPo

Design Description: Ground Control StationThe ground control station consists of two windows based laptop computers and a host of radio equipment tosupport communication with the aircraft in flight. The design intent of the ground station was to segregate theground crew responsibilities into three discrete tasks: emergency intervention, aircraft monitoring and tasking, andimage processing. The first task is accomplished by the safety pilot via the safety pilot transmitter. Monitoring andtasking will be performed by the control operator, at the command and control station (CCS) laptop computer.Finally, image processing verification will be performed by the vision operator and the image processing station(IPS) laptop computer.

One computer is to be part of the command and control station (CCS), where the vehicle operator can track vehicleperformance and update mission tasking in real time. The second computer is to be used as the image processingstation, where the vision operator will be able to monitor the target detection software and vehicle video feed, also inreal time. The various radios used are: a 2.4 GHz FHSS Spektrum R/C transmitter, for safety pilot control; a 3DRobotics 915 MHz FHSS telemetry radio for command/control data link with the autopilot; and a Range Video 1.3GHz analog video receiver to capture video feed from the aircraft.

Design Description: PayloadThe payload consists of two main subsystems: avionics and imaging. The avionics system includes thecommunications hardware, control logic hardware, and actuator assemblies on board the aircraft. The imagingsubsystem includes the image capture device, articulating camera mount, and image transmission hardware.

The avionics system can also be divided into three sub categories: communications hardware, control hardware, andactuators. The communications hardware consists of a Spektrum R/C 2.4 GHz FHSS receiver for safety pilot controland a 3D Robotics 915 MHz FHSS telemetry radio for autopilot telemetry and command.

Mission PlanningMission planning and performance monitoring of the aircraft are accomplished through the use of 3D Robotics’ open source Ardupilot Mega Mission Planner software package. This software package enables the command operator to monitor autopilot telemetry data, define mission waypoints and tasks, define mission boundaries and no fly zones, and update the commands to the aircraft in real time through the telemetry and command data link radio.

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Data ProcessingReal time processing of the image and spatial data collected by the aircraft is accomplished through a custom built

software package. Thispackage, the ORCAVisionSoftware Package v 1.0(OSP), is a full featuredcomputer vision programcapable of real time imageprocessing; target detection,classification, and location;and real time display of in-flight video feed withdetected target regionoverlays. The software alsofeatures the ability to havemanual cueing input, in theevent the operator discoversa possible target region notrecognized automatically bythe image processingalgorithms. Finally, thesoftware also features targetcharacteristic logs, actionable

intelligence logs, and manual editing of target characteristics, developed using Qt 4’s Model/View architecture.

Method of AutonomyAir vehicle autonomy is accomplished via 3D Robotics’ ArduPilot Mega (APM), an open source hardware, opensource software electronics package designed specifically for use in small, unmanned vehicles. The APM features amicrocontroller-in-series, full pass through architecture with onboard 9 DoF + GPS sensing capabilities for vehiclestate estimation, as well as two independent barometric sensors for altitude and airspeed measurement. Byintegrating these sensors with an Arduino based microcontroller, the APM is capable of full digital vehicle control,in various modes of operation. In addition to complete autonomous vehicle control, the APM also features modes formanual control/auto-stabilized flight, return –to-launch (RTL), and circling about a fixed waypoint. With proper gaintuning and tasking, the APM is also capable of completely autonomous air vehicle takeoff and landing.

Target Types Supported by Autonomous CueingUsing the OSP software described above, the system is capable of detecting, logging and reporting the basic type oftargets expected in the search area, along with their key characteristics. The targets are expected to be of basicgeometric shape, non-natural colors with varying degrees of contrast with the surrounding terrain, and alphanumeric

identifiers with varying degrees of contrast from the targetbackground. For this target type, the OSP is capable ofdetermining with reasonable accuracy all six keycharacteristics: GPS location, shape, background color,alphanumeric identifier, alphanumeric color, and orientation.For targets of other types, the manual cueing feature of theOSP will be utilized for identification and location.

Using the GoPro Hero 2, the camera pulls a single frame every32 milliseconds. The image is the converted from RGB (RedGreen Blue) to a grayscale copy to reduce the number ofchannels per pixel. This reduces the noise in the image. Anadaptive threshold is then applied to the grayscale image andconverted into binary black and white. The ORCAVision

software then extracts all the white contours from the image and places them into a vector for storage. The programthen goes through each contour in the storage vector and filters according to height, aspect ratio, or other

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Figure 6: ORCAVision Software Interface

Figure 7: ORCAVision Workflow

requrements, then creates a mask of the contour image. The program will attempt to fill in any missing informationfrom the contour image, if possible. It will then count the number of pixels in the contour image and compare it to apredefined value. If the pixel count is less than the predetermined value, it will reject the image.

If it is greater, it will accept the image and attempt to classifyit using a Support Vector Machine (SVM). Using the SVM,we train the system by feeding it shapes and non-shapes.ORCAVision currently supports 100 shapes and 100 non-shapes, and is trained in 3600 alphanumeric images, 100images of each alphanumberic. If the image is recognized as ashape, the program will continue, making three copies of theimage and sending each to a different classifier. K-NearestNeighbor (KNN) is used to classify alphanumeric character,and another KNN is used to classify the shape. Finally, aportion of the original image proceeds to color detectingclassification, where the segment is transferred from RGB toHue Saturation Value (HSV). HSV colorspace will tally the

percentage of hues the original color segment matches to, for example “X amount of times red”, and attempt toclassify the color using the results.

Test & Evaluation ResultsThe verification and validation of all requirements as defined in the Requirements Verification Matrix (RVM), is defined and governed by the Project ORCA Quality Control System. All test procedures and acceptance criteria are documented and controlled.

Iron Bird TestsConstruction of a Systems Integration Lab (SIL) was necessary in order to facilitate the testing required to verify the

system would be able to complete the required mission. A mock-up plane was constructed using the same dimensions as the actual air vehicle in order to simulate, as closely as possible, the effect certain characteristics would have on one another. Some of the tests conducted:

Electromagnetic Interference Tests: The payload rack was installed into the iron bird fuselage. All avionics and powerplant were powered on, aswell as video transmission. Telemetry link was established. Motors were powered up to full throttle, servos to full displacement. At this point

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Figure 8: Image Classifier Work Flow

Figure 9: Iron Bird Test Platform

servo motion and motor throttle were varied, and the results observed for discrepancies or unpredicted behavior. Thereceive station was moved throughout the lab, and the video and telemetry links were monitored for interference or disconnection.

Power Consumption:

System was powered on with DC ammeter attached to battery leads. The motor throttle was then varied through the operating range while power draw was recorded.

Table 3: Power Consumption Results

Thermal Profile:

During power consumption and energy tests, key temperature points were monitored using thermocouples:

Table 4: Thermal Profile Results

Mission Endurance:

Table 5: Mission Endurance Results

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Flowchart

Structure TestsAll incoming structure materials were documented conforming by their various manufacturers, as required by the Project ORCA Quality Control System. Additionally all structure materials received incoming inspection upon receipt to verify the quality andstructural integrity of each part.

The Federal Aviation Administration (FAA) System Design and Analysis Guidelines, Par. 7.f. [4.], states that “…compliance for a system or part thereof that is not complex may sometimes be shown by design and installation appraisals and evidence of satisfactory service experience on other airplanes using the same orother systems that are similar in their relevant attributes.”

As was noted in the detailed structure design descriptions, the maindesign considerations were simplicity and reliability. The system was conventional and no new or exotic characteristics were introduced. The designs selected for the structures were tried-and-true models which fit the FAA criteria (see Figure 8 )Additionally,

failure of structural elements such as wing, fuselage, tail, etc were deemed catastrophic failures and therefore fell within the purview of FAA similiarity and use of qualitative assessment.

Therefore, structure components are justified by similarity, in accordance with FAA guidelines as well as the Project ORCA Quality Control standards. However, at integration the structure must be considered as something else entirely, since it may no longer be considered “not complex” once the components are assembled. At this point in theproject, the team must rely on flight test data in carefully controlled environments in order to justify safe use of the aircraft.

Flight TestsProject ORCA initially ran test flights utilizing the autopilot/payload rack in an off-the-shelf model airplane in order to test the capabilities of the autopilot . Once the structure was completed, the structure was tested with minimal avionics on board under manual control. With this data, the effectiveness of both the autopilot and structure were validated. Subsequent testing showed the two working together effectively. The greatest challenge for the autopilot to date is autonomous takeoff, however as mentioned the Titan UAV Team has high expectations for a favorable performance as more and more test flights are completed.

Software TestingWithout a doubt, the most extensive testing conducted so far has been the ORCAVision software testing. The ORCAVision software is able to successfully identify most characteristics of most target types. Preliminary testing was conducted using an inexpensive webcam, however upon moving to the GoPro camera, it was found that the increased resolution dramatically improved target indentification capabilities.

Safety Considerations and ApproachSince safety is a key performance parameter, the team has endeavored to integrate safety considerations at every stepin the design, manufacturing and operating process.

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Quality Control/Risk ManagementSince safety is one of the paramount requirements of the competition, a Quality Control/Risk Management System was designed for Project ORCA from the ground up. The purpose of the Quality Control System is to manage risk, mitigate failures, and prevent catastrophic failure.

One might wonder why a quality system is necessary: “Quality is a vital part of risk management… Rigid adherenceto procedural requirements is necessary in high-risk, low-volume manufacturing . In the absence of large samples and long production runs, compliance to these written procedures is a strong step toward ensuring process, and thereby; product consistency. To address this, NASA requires QA programs to be designed to mitigate risks associated with noncompliance to those requirements.” [1.]

Project ORCA operates on a quality system as outlined in SAE’s Aerospace Quality Standard AS9100C [3.], which incorporates the requirements of ISO9001:2008. Under this standard, it is the responsibility of the organization (Titan UAV)to design and implement a quality standard. This means the organization defines its quality system (based on the guidelines provided), then is responsible for implementing and acting in accordance with that system.

Project ORCA’s Quality Systemis defined by Project ORCA Controlled Document QSM-0002: Quality Policy. The Quality Policy states that ProjectORCA shall have control over all documents in use, including drawings, specifications, work and assembly instructions, and test procedures. It is important to have control of all documents so that fabrication or test is not conducted based on conflicting revisions.

The document control system is governed by QSM-0003: Document Control. Documents are numbered according toclassification, as listed in Figure.

Table 6: ORCA Doc Control Naming Conventions

Prefix

Revision No. Type of Document

200- A, B, C, D Specification

300-000, 001, 002

Manufactured Components

400- 00, 01, 02 Forms500- 00, 01, 02 Work InstructionQSM- 00, 01, 02 Quality Systems Manual

QSI- 00, 01, 02Quality Systems Instruction

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Figure 11: Example of a Project ORCA Controlled Document

Before a document can be used, it must be released. All released documents follow the released document procedure, which includes initiating a change order, then are logged into Document Control, and signed off on by allmembers of the team. All team members are responsible for verifying the current revision of a document before use.

In addition to document control and process control, the Quality Control System governs the safety requirements and test plan for Project ORCA.

Safety FeaturesTo mitigate the risk of unwarranted actuation of control surfaces and motors on the ground, a kill switch panel has been designed and integrated into the air vehicle. These switches, installed in the aft underbelly of the fuselage, allow the aircraft operators to keep all actuators and propulsion systems isolated from power until the aircraft has been deemed safe for mission start and after the mission has been completed.

Fail-Safe Design ConceptFAA System Design and Analysis requirements define the importance of a failsafe design: “In any system or subsystem, the failure of any single element, component, or connection during any one flight… should be assumed, regardless of its probability. Such single failures should not prevent continued safe flight and landing, or significantly reduce the capability of the airplane or the ability of the crew to cope with the resulting failure conditions.” [4.]

To address this, several layers of redundancy and isolation have been designed into the avionics and propulsion systems. The first level of isolation is between the propulsion and avionics systems: they are separately powered on independent buses, reducing the risk of failure of one system due to the failure of the other. Within each system, we employ redundant power buses: the avionics system is powered by two independent batteries, and the propulsion system is as well. This allows these systems to be designated as One-Fault Tolerant (1FT), meaning we can endure a single point of failure in the system and still have the ability to maintain control of the aircraft. Another source of redundancy in the avionics system is the multiple receiver antenna modules. The aircraft’s radio receiver can function properly with only one of these antenna modules, yet we use three, to give us Two Fault Tolerance (2FT) in the radio link between safety pilot and aircraft.

Failure Modes and Effects Analysis (FMEA)This is a bottom up analysis to determine the probability of component failures like actuators, generators, computers,etc. For each subsystem on the aircraft (and in the ground station), the design was reviewed for possible failure of each component and how the system would cope with such failures. The failure modes were analyzed for three possibilities:

1) Critical Failure: Low Risk of Occurrence

2) Critical Failure: High Risk of Occurrence

3) Non-Critical Failure: Low or High Risk of Occurrence

For non-critical failures, no action was taken as it was determined that this particular failure mode would not cause aserious issue with performance of the system. Critical failure modes were split into two categories: low and high risk. For low risk critical failures, action taken (or planned to be taken) often included various forms of tests, to demonstrate the unlikelihood of an actual failure in that mode. Those critical failures which were deemed to have a relatively high risk were considered in detail, and the system design evaluated for fault tolerance. In any instance where there was not a satisfactory outcome of a possible subsystem or component failure, action was taken to redesign the parent system, the subsystem, or the component as necessary.

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Table 7: Excerpt: FMEA Analysis Table

ConclusionIn conclusion, the CSUF Titan UAV Team is proud of their achievements to date. Project ORCA is a functional aircraft with autonomous and manual capabilities, image recognition capabilities, and a ground control station capable of real-time data output.

Additionally, Project ORCA has generated a substantial platform from which future Titan UAV teams may build. This includes an in-depth data archive, complete with best practices and lessons learned, as well as an efficient and well-thought out Quality Management and Safety platform.

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References1. National Aeronautics and Space Administration. NASA Systems Engineering Handbook. Rev I ed. Vol.

NASA/SP-2007-6105. Washington, DC, 2007. Print.2. Association for Unmanned Vehicle Systems, Int'l. 2013 Undergraduate Student Unmanned Aerial Systems

Competition Final Request for Proposal. Working paper no. RFP 20130315 Rev. F. Print3. SAE Aerospace. AS9100C Aerospace Standard. Print.4. US Deptartment of Transportation, and Federal Aviation Administration. Advisory Circular: System Design

and Analysis. N.p.: n.p., 1988. Print.

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