Design Review (PDR) - Home | University of Colorado Boulder · Preliminary Design Review (PDR) ... CERUNAS Preliminary Design Review Rev- 5 . ... 3.3V signal and UAV maintains flight

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-

2

Overview

Project Summary

Feasibility Analyses (By Subsystem)

Manned A/C Componentry

Communication Componentry

sUAS Componentry

Test

Modeling

Future Work

Backup Charts


3

Project Summary


4

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-

5

Project Summary

Concept of Operations


6

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.


7

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.


9

Project Summary

Sensing Concept of Operations


10

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


11

Project Summary

Avoidance Concept of Operations


12

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


13


7 Feasibility Analysis

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


16

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.


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


17


Manned A/C Componentry Battery Trade Study


18

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


Manned A/C Mass, Power, Cost


19

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


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.


21


Communication-Feasibility Analysis Drivers


Transceiver Trade Study


22

XBee transceiver has flight heritage on sUAS Data Hawk

Interference concern with existing Xbee transceivers on sUAS Data Hawk


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


23


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


24

sUAS Componentry 25


sUAS – Feasibility Analysis Drivers



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.


26


27

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


sUAS – Feasibility Analysis Drivers


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


28

• 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


sUAS Mass, Power, Cost


29

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


30


Test - Feasibility Analysis Drivers



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.


31


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


32



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


33



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


34


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


35


Modeling - Feasibility Analysis Drivers



A/C Dynamics Modeling

No concerns N/A N/A

MAEC Modeling

Post-CERNUNAS MAEC modeling CAS-SYS-002


Autopilot Modeling

No concerns N/A N/A

CAS Modeling

No concerns N/A N/A


36

CAS


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


37


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


38

Summary of Feasibility and Future Work


39

Summary of Feasibility

Baseline Recap


40

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


41

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.]


42

http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/systemops/aaim/organizations/uas/coa/



https://recuv-ops.colorado.edu/projects/faa_coa/wiki




Backup Charts


43

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


44

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.


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


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


45

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


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.


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


CAS-SYS-006

All avoidance maneuvers implemented by the CAS shall aim for recoverability of sUAS flight after mitigation of the collision situation.


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.



CAS-SYS-008 The sUAS elements of the CAS shall draw no more than 50mA of current at 6V.



CAS-SYS-009 sUAS development shall promote ease of implementation.



46


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.



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


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


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


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


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


CAS-SYS-017 Sensitivity analysis shall be carried out in conjunction with all CAS computer models.

Project Requirement


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.



47


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)


48

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)


49

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


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)


50


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


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


51

Documents

Design Review (PDR) - Home | University of Colorado Boulder · Preliminary Design Review (PDR) ... CERUNAS Preliminary Design Review Rev- 5 . ... 3.3V signal and UAV maintains flight