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Preliminary Design Review
(PDR)
Collision Encounter Reduction for UNmanned Aerial Systems (CERUNAS)
University of Colorado at Boulder
Department of Aerospace Engineering Sciences
17 October 2013
CERUNAS Team
Eric Brodbine Quinn McGehan
Jackson Beall Colby Mulloy
Garrett Brown Mark Sakaguchi
Chad Hotimsky Chris Young
CERUNAS Preliminary Design Review Rev-
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Overview
Project Summary
Feasibility Analyses (By Subsystem)
Manned A/C Componentry
Communication Componentry
sUAS Componentry
Test
Modeling
Future Work
Backup Charts
CERUNAS Preliminary Design Review Rev-
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Project Summary
CERUNAS Preliminary Design Review Rev-
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Project Summary
Background and Project Objective PROBLEM
Increase in unmanned aircraft systems (UAS) from recreational flyers, researchers, industry
No UAS has been certified to satisfy See and Avoid requirements in VFR conditions
Future aircraft (manned and UAS) need a collision avoidance system
SOLUTION
Design a collision avoidance system(CAS) for sUAS (< 2 lbs)
sUAS
Detects beacon from unmanned aircraft
Interrupts the sUAS autopilot to evade the manned aircraft flight path
Manned Aircraft
Propeller-driven (100 m/s)
Flying straight and level
Flying in uncontrolled airspace over remote terrain CERUNAS Preliminary Design Review Rev-
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Project Summary
Concept of Operations
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Project Summary
Levels of Success Summary of Success Level 1
Verify Sensing Functionality and characterize Manned Aircraft Encounter Cone (MAEC) via Ground Test.
Summary of Success Level 2
Verify and Characterize Avoidance Functionality only via Flight Test.
Summary of Success Level 3
Verify full CERUNAS functionality via flight test.
CERUNAS Preliminary Design Review Rev-
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Project Summary
Project Functional Block Diagram 8
Project Summary
Baseline Design - Sensing
GPS with pressure altitude is the optimal design GPS with pressure altitude on manned aircraft transmits position and
heading
Receiver on sUAS decodes manned aircraft parameters and calculates if an avoidance maneuver is necessary using own sUAS GPS
Note: Illumination design option will be researched further as a feasible baseline design.
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Project Summary
Sensing Concept of Operations
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Project Summary
Baseline Design – Avoidance
Flight Termination Mode is the optimal design
Interfaces with the autopilot through digital I/O pin (nominally at 3.3V)
Flight Termination Mode (FTM) already a feature on Data Hawk sUAS
If sensing option sets digital I/O pin low (0V), sUAS initiates FTM, else sUAS continues on autopilot flight path
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Project Summary
Avoidance Concept of Operations
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1. Manned Aircraft GPS and Altitude Locations Transmitted
2. sUAS GPS and Altitude Locations Measured and Manned Aircraft Telemetry Received
3. Microcontroller on sUAS Calculates Flight Paths of Manned aircraft and sUAS and Determines if sUAS is in Collision Cone
4. Microcontroller stops outputting the 3.3 V signal and interrupts the autopilot forcing UAV into a dive
4. Microcontroller Continues to output 3.3V signal and UAV maintains flight path
Return to step 2
Yes No
(XX.XXXXN, XX.XXXXE, XXXft)
Wireless Transmission
GPS and Altitude Position
Calculated Flight Path
Legend
Avoidance Flight Path
Feasibility Analyses Critical Project Elements Manned A/C Componentry Communication Componentry sUAS Componentry Test Modeling
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CERUNAS Preliminary Design Review Rev-
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Critical Project Elements
Project Element Identifier
Critical Project Element Description Rationale for Element
1 The CAS must determine that the sUAS is in the encounter cone of a manned A/C based on reception of a signal provided by the manned A/C
Indication of potential manned A/C-sUAS collisions
2
The manned A/C mountable CAS transmission device must be able to indicate either or both: The location and heading of the A/C Encounter cone boundaries for a sUAS
Indication of potential manned A/C-sUAS collisions
3 The CAS must complete any sUAS maneuvers required to move the sUAS outside of the manned aircraft encounter cone
Avoidance of manned A/C-sUAS collisions
4 The sUAS elements of the CAS must have a mass of less than 100g
Weight key to effective integration of CAS with existing sUAS components
5 Telemetry data for the sUAS must be collected and downlinked for any collision avoidance maneuvers
Need to understand CAS effectiveness in real-world flight and to validate mission success
6 The CAS transmitter and receiver units must each be mass producible for less than $100
- Cost-effective compared to cost of sUAS - Cost-effective for private pilot implementation
Manned Aircraft Componentry
15
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Feasibility Analysis
Manned A/C - Feasibility Analysis Drivers
Concerns which Drive Feasibility Analysis
Concern Description Requirement Requirement Text
Venus GPS Logger
Cost because it is a over half of the $100 production cost
CAS-SYS-018
The CAS elements for both the manned A/C and sUAS platforms shall be demonstratably reproducible for $100 +/- 10% based on manufacturer input.
Power System
Ability to power manned A/C components with minimal impact to manned A/C
CAS-SYS-004
The manned A/C mountable element of the CAS shall not impact the functionality of any manned A/C HW or communications systems and shall have the ability to comply with applicable FAA regulations.
Feasibility Analysis
Manned A/C Componentry GPS Trade Study
Desired GPS Characteristics
GPS L1 C/A code
Accuracy: < 2.5 m CEP
Power Supply: 2.7 – 3.6 V
Communication Interface: RS-232, RS-422, USB, UART
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Feasibility Analysis
Manned A/C Componentry Battery Trade Study
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Lithium iron phosphate battery ideal design for manned A/C GPS
Specific power: >300 W/kg
Cost: $4.50 - $9.00 (depending on size)
Safety: minimal risk of delamination or explosion
Instrumentation Mass Current Voltage Cost
Communication Device: Xbee Pro 900 HP
8g 29 mA 2.1-3.6V $100.00
Microcontroller: PIC18F47J13
1g 1.44 mA typical
2-3.6V $2.76
GPS: Venus GPS Logger <1 g 29 mA 2.7-3.6V $59.95
Battery: LiFePO4 18500 31.2 g 800 mAh 3.2V $2.99
Requirement <100g 800 mAh 3.3 V >$100
Low Concern Medium Concern High Concern
Feasibility Analysis
Manned A/C Mass, Power, Cost
CERUNAS Preliminary Design Review Rev-
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Mass Consideration is low concern; both systems weigh 9 g cumulatively
Current Consideration is low concern; battery provides ample power
Voltage Consideration is low concern; both systems operate with 3.3V
Cost Consideration is medium concern; combined system >$100
Mass production will lower cost
Communication Componentry
20
Requirements driving Communication System Development
Concern Description Requirement Requirement Text
Ability to detect and characterize the motion of an A/C at a minimum range of 2 km.
CAS-SYS-001
The initial volume of the MAEC for the manned A/C shall extend 2km in front of the manned A/C at an angle defined by
the expected velocities for both the sUAS and manned A/C
Communication System must be low mass CAS-SYS-007 The sUAS elements of the CAS shall have a mass of less than 100g.
Communication System must be low power CAS-SYS-008 The sUAS elements of the CAS shall draw no more than 2.5W of power.
Communication System must transmit enough data to fully characterize the motion of an A/C for Avoidance
and Telemetry
CAS-SYS-010 Telemetry data for any collision avoidance maneuvers shall be downlinked and saved on the existing sUAS telemetry stream.
CAS-SYS-011
Telemetry data for any collision avoidance maneuvers shall be uniquely recorded for a period beginning one (1) maneuver duration before the maneuver start time and extending one (1) maneuver duration beyond the maneuver end time.
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Feasibility Analysis
Communication-Feasibility Analysis Drivers
Feasibility Analysis
Transceiver Trade Study
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XBee transceiver has flight heritage on sUAS Data Hawk
Interference concern with existing Xbee transceivers on sUAS Data Hawk
Feasibility Analysis
Transceiver Selection
XBee Pro 900 HP Frequency 902-928 MHz
Data Transfer Rate 10 or 200 Kbps
Transmit Power Up to 24 dBm
Supply Voltage 2.1 to 3.6 VDC
Transmit Current 215 mA
Receive Current 29 mA
Max Published Range 14 km w/ dipole antenna
Data Interface UART (3V), SPI
Mass 8g
Cost (Low Volume) $70 - $150
• Available with RPSMA, wire, or U.FL Antenna
CERUNAS Preliminary Design Review Rev-
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Feasibility Analysis
RF Link Budget Feasibility Analysis
Overall Transmitter Gain: 24 dBm Receiver Gain (Antenna): 2.1 dB Operating Frequency: 915 MHz Required Operating Range: 2 km Environmental Impedance Factor (n): 2.5 Received Power = -74.97 dBm
XBee Pro 900HP is rated for <10% packet error rate at -110 dBm @ 200 Kbps Packet Error Rate << 10%
Data Rate > 180 Kbps
Pr = Power Received Pt = Power Transmitted Gt = Transmitter Gain Gr = Receiver Gain λ = Wave length d = Distance of transmission n = environmental factor
Determine Data Throughput Capability at Range
CERUNAS Preliminary Design Review Rev-
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sUAS Componentry 25
Feasibility Analysis
sUAS – Feasibility Analysis Drivers
Concerns which Drive Feasibility Analysis
Concern Description Requirement Requirement Text
Autopilot Interface
Need I/O pin to interface with autopilot
CAS-PRJ-004 The sUAS elements of the CAS shall have minimal
impact on existing sUAS componentry. Changes to autopilot may make avoidance system prohibitively
difficult or complex to implement
Power Limitations
Limiting power consumption to the 2.5W available on the sUAS
CAS-SYS-008 The sUAS elements of the CAS shall draw no more
than 50mA at 6V of power.
Telemetry Data Recording
Recording telemetry data during avoidance to demonstrate success of
system CAS-SYS-010
Telemetry data for any collision avoidance maneuvers shall be downlinked and saved on the
existing sUAS telemetry stream.
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Concern: Need available I/O port for Autopilot interface
Input from Customer
There is a digital I/O pin available
Concern: Changes to autopilot may make avoidance system prohibitively difficult or complex to implement
Input from Customer
Changes to Autopilot will be small
No concerns regarding feasibility of Autopilot at this time
Feasibility Analysis
sUAS – Feasibility Analysis Drivers
Feasibility Analysis
Microcontroller Choice Microcontroller PIC18F47J13 ATMEL SAM D20J17 ATMEGA128
Voltage Range 2-3.6 V 1.62-3.6V 1.8-5.5V
Program Memory 128K 128K 128K
Data Memory 3.8K 16K 16K
Peripherals 8 6 8
Timers 8 8 6
ADC 13 Channel 12-bit 20 Channel 12-bit 8 Channel 10-bit
Speed 48 MHz 48 MHz 20 MHz
Cost $2.76 $3.53 $7.22
CERUNAS Preliminary Design Review Rev-
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• Desired Microcontroller Characteristics • Familiarity • 3.3V Operation to match Communication
System • Maximize
• Peripherals • Program Memory ≥ 128k • Data Memory ≥ 4k • ADC Resolution ≥ 10-bit
• Minimize • Power Consumption
Instrumentation Mass Current Voltage Cost
Battery: LiFePO4 18500
31.2 g 800 mAh 3.2V $2.99
Communication Device: Xbee Pro 900 HP
8g 29 mA 2.1-3.6V $100.00
Microcontroller: PIC18F47J13
<1g 1.44 mA typical 2-3.6V $2.76
Requirement <100g 800 mAh 3.2 V <$100
Low Concern Medium Concern High Concern
Feasibility Analysis
sUAS Mass, Power, Cost
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Mass Consideration is low concern; all systems weigh 50 g cumulatively
Current Consideration is low concern; all systems combined accumulate to 50 mA
Voltage Consideration is low concern; all systems operate at 3.3V
Cost Consideration is medium concern; combined system costs >$100
Mass production will lower cost
Test and Modeling Ground Test for Success Level 1
Flight Test for Success Level 2 Flight Test for Success Level 3 FAA Testing Feasibility
CERUNAS Preliminary Design Review Rev-
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Feasibility Analysis
Test - Feasibility Analysis Drivers
Concerns which Drive Feasibility Analysis
Concern Description Requirement Requirement Text
Ground Testing
No Concerns N/A N/A
Flight Testing
Ability to Comply with FAA Guidelines -- Need to Comply with US government airspace limitations
Characterization of MAEC Geometry and sUAS behavior during avoidance and Verification of CAS Functionality
based on Test
CAS-SYS-002
The post-CERNUNAS volume of the MAEC shall be determined by the expected velocities of the sUAS and manned A/C along with the time necessary for the sUAS to leave the MAEC at a typical velocity.
CAS-SYS-006 All avoidance maneuvers implemented by the CAS shall aim for recoverability of sUAS flight after mitigation of the collision situation.
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Feasibility Analysis
Test - Verification of Success Level 1
Precedent for similar test set by Dr. Lawrence
Allows for simple characterization of MAEC
Level 1 Testing is a mild concern
No difficult technical elements
No special permissions
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Feasibility Analysis
Test - Verification of Success Level 2
Concern: ability to characterize avoidance based on test (CAS-SYS-006)
See FAA Regulations chart
CoA Height limit may cause issues with necessary fall distance
See FAA Regulations chart
FAA Limitations are mild concern
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Feasibility Analysis
Test - Verification of Success Level 3
Concern: CoA height limit could limit testing
Scaled test allows for meaningful verification
Ground tests could be carried out with similar methodology
Concern: FAA restrictions on weather balloon flight
See FAA concerns section
With Current GPS System, weather balloon is not necessary
FAA Limitations are mild concern
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Feasibility Analysis
Test - FAA Feasibility [1,2] Concern: Procurement of CoA
“FAA will provide a formal response within 60 days from … [submission].”
CoAs above 122m (400ft) are difficult to obtain, optimal test altitude is 300m (984ft).
Can scale test to accommodate lower altitude
Concern: Ability to broadcast from moored balloon
FAA allows moored balloons to 500ft AGL without certification
Issue if CoA > 400ft is approved
Can scale test to accommodate lower altitude, use permanent high point
With GPS, altitude mounted transmitter is unnecessary
FAA compliance is a mild concern
Contingency plans and test flexibility means that test can continue with minimal redesign
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Feasibility Analysis
Modeling - Feasibility Analysis Drivers
Concerns which Drive Feasibility Analysis
Concern Description Requirement Requirement Text
A/C Dynamics Modeling
No concerns N/A N/A
MAEC Modeling
Post-CERNUNAS MAEC modeling CAS-SYS-002
The post-CERNUNAS volume of the MAEC shall be determined by the expected velocities of the sUAS and manned A/C along with the time necessary for the sUAS to leave the MAEC at a typical velocity.
Autopilot Modeling
No concerns N/A N/A
CAS Modeling
No concerns N/A N/A
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CAS
Feasibility Analysis
Modeling - System Modeling
Compute MAEC geometry from model
Autopilot Simulation
Simulated manned A/C
motion
Determine whether sUAS in MAEC
Simulated sUAS A/C motion
Simulated GPS datal from sUAS GPS module
Simulated GPS data from
manned A/C
If in MAEC send signal to autopilot
KEY MAEC Model
CAS Simulation
Simulated GPS signal
A/C motion simulation
Autopilot Simulation
Purpose of Models/Simulations:
Simulate system in SW to provide initial verification of functionality and characterization of post-A/C MAEC
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Feasibility Analysis
Modeling - Encounter Cone Modeling
Pre-CAS Manned A/C Encounter Cone (MAEC) defined by nominal velocities of manned A/C and sUAS (See Project Description)
Extends out 2 km in front of manned aircraft
Initial area at x = 0 is ellipse formed by average GAA wingspan and height
y slope:
z slope:
Concern: Post CAS MAEC modeling
No simple mathematical formula to
Use results of testing to characterize encounter cone
Aircraft/regime V (m/s)
Manned aircraft 100
sUAS horizontal 10
sUAS climb/descent 3
sUAS Dimensions Length (m)
Wingspan 12
Height 3
o5.71061.0tan
o1.718403.0tan
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Summary of Feasibility and Future Work
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Summary of Feasibility
Baseline Recap
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Aspect Feasibility Studies Needed Critical Project Element
Sensing GPS has low feasibility concerns
Illumination feasibility requires more research and professional input
The CAS must determine that the sUAS is in the encounter cone of a manned A/C based on reception of a signal provided by the manned A/C
Avoidance GPS-based flight termination mode has low feasibility concerns
More detailed characterization of flight termination mode
The CAS must complete any sUAS maneuvers required to move the sUAS outside of the manned aircraft encounter cone
Cost Budget
LiFePO4 battery, Venus logger GPS, and PIC18F microcontroller fit within given cost
Further research into unit costs specific to size/quantity of componentry required
The CAS transmitter and receiver units must each be mass producible for less than $100
Link Budget Very low packet rejection at range with given XBee receiver
Data throughput requirements for GPS transmission
Telemetry data for the sUAS must be collected and downlinked for any collision avoidance maneuvers
Mass Budget All componentry studied fits within given mass allowance
Further investigation into additional hardware required
The sUAS elements of the CAS must have a mass of less than 100g
Future Work
Concern Areas/Critical Tasks Contingency Plans for Testing if FAA Approvals Fall Through
A better understanding needs to be gained of how FAA regulations will impact project
Robust ground test contingency plans need to be put in place
sUAS Componentry Cost, Manned A/C Componentry Cost
Mild feasibility concerns surrounding cost, but bulk purchasing quotes will help drive down cost and mitigate concerns
Contacting distributors will allow for better estimate of mass production cost
Trade Study for Illumination Sensing Methodology
Need to meet with experts to gain better understanding and conduct a meaningful trade study
If the BL design changes from that presented herein, PAB will be re-briefed on design
CERUNAS Preliminary Design Review Rev-
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References [1] “Certificate of Authorization or Waiver (COA),” Federal Aviation Administration, November 2012. [http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/systemops/aaim/organizations/uas/coa/. Accessed 10/8/13.]
[2] Lang, J. P., “FAA COA,” RECUV, 2013. [https://recuv-ops.colorado.edu/projects/faa_coa/wiki. Accessed 10/8/13.]
CERUNAS Preliminary Design Review Rev-
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Backup Charts
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Backup Charts
Acronym Glossary Acronym or Term Definition
A/C Aircraft
A/C-GPS Manned Aircraft Global Positioning system
ADS-B Automatic Dependent Surveillance Broadcast
AFRL Air Force Research Laboratory (US)
CAS Collision Avoidance System
CERUNAS Collision Encounter Reduction for Unmanned Aerial Systems
CONOPS Concept of Operations
COTS Consumer Off The Shelf
FAA Federal Aviation Administration (US)
FBD Functional Block Diagram
GPS Global Positioning System
HW Hardware
IR Infrared
IREO Infrared Electro-Optical
LiDAR Light Detection and Ranging
MAEC Manned Aircraft Encounter Cone
sUAS Small Unmanned Aerial System
SW Software
UAS Unmanned Aerial System
CERUNAS Preliminary Design Review Rev-
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Backup Charts
Project Level Requirements
Requirement Number Requirement Text Requirement Driver Requirement Verification Method Child Requirements
CAS-PRJ-001
The CAS shall determine that the sUAS is in the encounter
cone of a manned A/C based on reception of a signal
provided a manned A/C in order to reduce the volume of the
MAEC by a factor of 1000.
Customer Requirement Test CAS-SYS-001
CAS-SYS-002
CAS-PRJ-002
The manned A/C mountable element of the CAS shall not
interface with existing manned A/C components while
maintaining the capability to indicate either the location and
heading of the A/C or encounter cone boundaries.
Customer Requirement Analysis CAS-SYS-003
CAS-SYS-004
CAS-PRJ-003
The CAS shall complete any sUAS maneuvers required to
move the sUAS outside of the MAEC while placing primary
focus on avoidance and secondary focus on preservation of
the sUAS.
Customer Requirement Test CAS-SYS-005
CAS-SYS-006
CAS-PRJ-004 The sUAS elements of the CAS shall have minimal impact
on existing sUAS componentry. Customer Requirement Observation
CAS-SYS-007
CAS-SYS-008
CAS-SYS-009
CAS-PRJ-005
Telemetry data for the sUAS shall be collected and
downlinked or saved for later download for any collision
avoidance maneuvers
Customer Requirement Test CAS-SYS-010
CAS-SYS-011
CAS-PRJ-006
Testing shall be carried out to allow for characterization and
validation of CERNUNAS system behaviors and to provide
discrete data for post-processing analysis of system
functionality.
Customer Requirement Test
CAS-SYS-012
CAS-SYS-013
CAS-SYS-014
CAS-PRJ-007
Computer models shall be developed to allow for
characterization, prediction, and initial validation of sUAS
behavior after CERNUNAS implementation.
Customer Requirement Test
CAS-SYS-015
CAS-SYS-016
CAS-SYS-017
CAS-SYS-018
CAS-PRJ-008
Element of the CERNUNAS system desiged for both the
manned A/C and sUAS platforms shall be mass reproducible
for less than $100.
Customer Requirement Analysis CAS-SYS-019
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Backup Charts
System Level Requirements (1 of 2) Requirement
Number Requirement Text
Requirement Driver
Requirement Verification Method Parent
Requirements
CAS-SYS-001
The initial volume of the MAEC for the manned A/C shall extend 2km in front of the manned A/C at an angle defined by the expected velocities for both the sUAS and manned A/C
Customer Requirement
Ground testing shall allow for verification of presence of standalone CAS components within encounter cone and characterizion of cone geometry with no more than 20% error.
CAS-PRJ-001
CAS-SYS-002
The post-CERNUNAS volume of the MAEC shall be determined by the expected velocities of the sUAS and manned A/C along with the time necessary for the sUAS to leave the MAEC at a typical velocity.
Team Analysis The MAEC shall be modeled before and after implementation of CERNUNAS to allow for characterization of MAEC dimensions and ensure the volume has decreased by a factor of 1000.
CAS-PRJ-001
CAS-SYS-003 The manned A/C mountable element of the CAS shall be able to indicate the MAEC with an error of no greater than 20%.
Team Analysis Telemetry shall be used to record the approach and presence in the stationary MAEC of the sUAS and CERNUNAS technology; analysis shall determine the error of the MAEC detection.
CAS-PRJ-002
CAS-SYS-004
The manned A/C mountable element of the CAS shall not impact the functionality of any manned A/C HW or communications systems and shall have the ability to comply with applicable FAA regulations.
Customer Requirement
Observation CAS-PRJ-002
CAS-SYS-005 All avoidance maneuvers implemented by the CAS shall comply with applicable FAA guidelines for sUAS operation.
Government Requirement
Observation CAS-PRJ-003
CAS-SYS-006
All avoidance maneuvers implemented by the CAS shall aim for recoverability of sUAS flight after mitigation of the collision situation.
Customer Requirement
Avoidance maneuvers instantiated by CERNUNAS shall be modeled to verify evasive maneuvers are appropriate for desired avoidance flight path, and that return of control to autopilot will ensure recoverability of original heading
CAS-PRJ-003
CAS-SYS-007 The sUAS elements of the CAS shall have a mass of less than 100g.
Customer Requirement
Observation CAS-PRJ-004
CAS-SYS-008 The sUAS elements of the CAS shall draw no more than 50mA of current at 6V.
Customer Requirement
Observation CAS-PRJ-004
CAS-SYS-009 sUAS development shall promote ease of implementation.
Customer Requirement
Observation CAS-PRJ-004
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CERUNAS Preliminary Design Review Rev-
Backup Charts
System Level Requirements (2 of 2)
CAS-SYS-010 Telemetry data for any collision avoidance maneuvers shall be downlinked and saved on the existing sUAS telemetry stream.
Customer Requirement
Observation CAS-PRJ-005
CAS-SYS-011
Telemetry data for any collision avoidance maneuvers shall be uniquely recorded for a period beginning one (1) maneuver duration before the maneuver start time and extending one (1) maneuver duration beyond the maneuver end time.
Team Analysis
Observation CAS-PRJ-005
CAS-SYS-012 All CERNUNAS test procedures shall be fully documented to ensure they are repeatable for a minimum of three (3) iterations
Project Requirement
Observation CAS-PRJ-006
CAS-SYS-013
CERNUNAS flight testing shall be fully telemetered to allow for post-processing characterization and verification of MAEC reduction by functional system.
Project Requirement
Observation CAS-PRJ-006
CAS-SYS-014 All testing of the CERNUNAS system shall comply with FAA regulations applicable to the operation of sUASs for research purposes.
Government Requirement
Observation CAS-PRJ-007
CAS-SYS-015 The manned A/C mountable element of the CAS shall not impact the functionality of any manned A/C flight characteristics or stability mechanisms.
Team Analysis
A/C dynamics-based simulations shall be used to characterize impact of the CERNUNAS package on sUAS flight characteristics.
CAS-PRJ-007
CAS-SYS-016 The methodology and assumptions made for all CAS computer models shall be fully documented.
Project Requirement
Observation CAS-PRJ-007
CAS-SYS-017 Sensitivity analysis shall be carried out in conjunction with all CAS computer models.
Project Requirement
Observation CAS-PRJ-007
CAS-SYS-018
The CAS elements for both the manned A/C and sUAS platforms shall be demonstratably reproducible for $100 +/- 10% based on manufacturer input.
Customer Requirement
Observation CAS-PRJ-008
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CERUNAS Preliminary Design Review Rev-
State of an aircraft given by:
Where
is inertial position of A/C in inertial reference frame
is A/C orientation expressed in Euler angles
is inertial velocity in body reference frame
is the angular velocity expressed in body coordinates
x = [rii,ob/i,vi
b,wb/i
b ]T
rii = [xi, yi, zi ]
T
ob/i = [f,q,j ]T
vib = [u,v,w]T
wb/i
b = [p,q, r]T
Backup Charts
Equations of Motion for A/C Modeling (1 of 2)
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Can solve EOM using numerical integrator
Inertia tensor can be determined experimentally to determine impact of physical characteristics on flight performance
Backup Charts
Equations of Motion for A/C Modeling (2 of 2)
CERUNAS Preliminary Design Review Rev-
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Desired Trait Weight Raw Weight
System range 0.15 8
Field of view 0.09 5
Ranging accuracy 0.16 9
Ease of implementation
0.11 6
sUAS mass budget 0.13 7
sUAS power budget 0.09 5
Impact on manned platform
0.07 4
Detection accuracy 0.16 9
Cost 0.05 2
Desired Trait Weight Raw Weight
Ease of implementation 0.15 8
Impact on existing sUAS components
0.09 5
sUAS platform independence
0.16 9
Post-maneuver recoverability
0.11 6
Cost 0.13 7
Power 0.09 5
Avoidance Sensing
Backup Charts
Trade Study Weights (1 of 2)
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Desired Trait Weight Raw Weight
System channels 0.12 4
Update rate 0.21 7
Position accuracy 0.26 9
Power 0.24 8
Requisition time 0.18 6
Cost 0.24 8
Desired Trait Weight Raw Weight
Safety 0.14 4
Life 0.21 6
Power supply 0.36 10
Cost 0.29 8
Backup Charts
Trade Study Weights (2 of 2)
Desired Trait Weight Raw
Weight Requirement Tie-In
Frequency 0.02 1 CAS-SYS-010
Data Transfer Rate
0.16 8 CAS-SYS-011
Transmit Current 0.12 6 CAS-SYS-008
Receive Current 0.20 10 CAS-SYS-008
Transmit Power 0.16 8 CAS-SYS-001, CAS-PRJ-004
Supply Voltage 0.02 1 CAS-SYS-008
Range 0.20 10 CAS-SYS-001
Comm Protocol 0.08 4 CAS-SYS-010
Cost 0.06 3 CAS-PRJ-008
Battery Choice
GPS Units
Transceiver
CERUNAS Preliminary Design Review Rev-
51