frr presentation april 5, 2012 1. eric p o team leader o payload manager o documentation manager...
TRANSCRIPT
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FRR Presentation
April 5, 2012
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• Eric Po Team Leader o Payload Manager o Documentation Manager
• Michael Bo Building Team Manager o Safety Manager
• Sean Ko Outreach o Materials Manager
• Jacob Eo Launch Manager o Budget Manager
• Mike Po Technology Manager o Equipment and Facility Manager
• Michael Go Recovery Manager o Communications Manager
• Brian Go Technical Manager o MSDS Manager
Lake Zurich Rocketry - Team Responsibilities
Lake Zurich High School
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FRR – Final Launch Vehicle Dimensions
Final Launch Vehicle Dimensions
Launch Vehicle Specifications
Length Diameter Mass
90.75 In 6.16 In 456.14Oz
Center of Gravity
Center of Mass
Stability Margin
45.27 In 64.91 In 3.22
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FRR – LV Key Design Features
System Rationale Characteristics
A - Nose Cone Part of payload - needs to be durable Fiberglass with Ogive design
B - Payload Engineering experimentDesigned to hold all components, deploy easily, able to maneuver, and be durable.
C - Payload Tube Lightweight and durable 6" Carbon Fiber - fiberglass too heavy.
D - Avionics Bay Standard design for redundant ejection charges.Screws attach to payload tube, and shear pins to booster tube for ejection.
E - AV Bay CollarHolds the arming switches - can be easily armed from outside of LV.
2" collar is adequate for arming switches and for vent hole for altimeter.
F - Drogue ChuteDesign to eject with payload and allow LV to descend with wind.
28" Nylon chute that is attached with quick links to eyebolts in bulkplate on Avionics Bay.
G - Main Chute Slows the LV down to safe landing velocity.108" Nylon chute that deploys at 1,000' to reduce impact of winds.
H - Booster TubeNeeds to be lightweight and durable to resist zippers.
6" Carbon Fiber - fiberglass was too heavy for the motor requirement.
I - CradleDesigned to absorb some of the stress on tube from deployment of main.
Connects to the shock cord at the edge of the booster tube.
J - Motor Mount Standard motor mount system for 54 mm motor. Using a K1050W motor from Aerotech
K - FinsAttached to motor tube, and sized to provide stable flight.
Fiberglass fins provide durable system
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Launch Vehicle Key Design Features
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FRR – Final Motor Choice – 1 of 3
Final Motor Selection - AeroTech K1050W
Motor Subsystem Construction
A - Centering Rings• Made from ¼” birch plywood.• Forward ring is doubled to increase
strength for main chute deployment.• Eye bolt is anchored into the forward
centering rings for main chute shock cord anchoring.
B - Fins• Fins extend through the airframe, and
are glued to the motor housing.• This increases strength.
C - Motor Tube• Aluminum motor tube that holds the
K1050 motor and slides into the kraft motor housing.
• Extends into the motor housingD - Retention Ring
• Holds the K1050 motor into the motor tube
E - Anchor bolts and clips• Used to clip over the retention ring, and
holds the motor securely.
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FRR– Final Motor Choice – 2 of 3
Final Motor Selection - AeroTech K1050W
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FRR– Final Motor Choice – 3of 3
Motor Specifications Diameter: 54.0mmLength: 62.7cmTotal Weight: 2203gProp. Weight: 1265gAverage Thrust: 1132.9NMaximum Thrust: 2172.0NTotal impulse: 2426.4NsBurn Time: 2.1s
Thrust Curve
Final Motor Selection - AeroTech K1050W
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FRR – Rocket Flight Stability Margin
Rocket Stability Margin
Length Diameter Span Mass (w/ motor)
90.75 in 6.16 in 15.66 in 456.14 Oz
Motor CG CP Stability Margin
K1050W 45.2767 in 64.9076 in 3.22
CPCG
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FRR– Thrust to Weight ratio and Rail Exit Velocity
Thrust to Weight Ratio and Rail Exit Velocity
Launch Information
Thrust to Weight Ratio 8.936
Rail Exit Velocity 68.87 ft/sec
Launch Rail Length 96"
Rail Button Size Fits Standard 1" rail
Flight Information (10 mph winds)
Prediction Launch Vehicle Payload
Time to Apogee 16.704 sec 16.704 sec
Maximum Acceleration 326.68 ft/s/s 326.68 ft/s/s
Maximum Velocity 566.59 ft/s 566.59 ft/s
Time to Landing 109 sec. 227 sec.
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FRR – Mass Statement
Mass Statement
Mass Statement
System Mass oz. Mass lbs.
Booster Tube 124.3 7.77lbs.
K1050 Motor 77.7 4.86lbs.
AV Bay 52.0 3.25lbs.
Payload Tube 40.8 2.55lbs.
Payload 84.5 5.28lbs.
Nose Cone 33.3 2.08lbs.
Recovery 37.5 2.34lbs.
Paint 6.0 0.38lbs.
Total Mass 456.1 oz. 28.51lbs.
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FRR – Recovery Systems – 1 of 3
Recovery Systems
Recovery Sub-Systems
Drogue Chute 28" - LOC Precision LP-28 - Rip-stop Nylon
Main Chute 108" - Rip-stop Nylon
Shock Cord 1/2" Tubluar Kevlar - 7500 lbs rated - Drogue and Main 30' length
Payload Chute 42" Round Custom (8" vent in top for added stability)
Nomex Used to protect all parachutes from heat of ejection charge
Eye Bolts Used to hold the shock cords to bulk plates - AV Bay and Payload
U-Bolts Used to hold the shock cord to bulkp late in the booster tube
Quick Links Used to attach shock cords to eyebolts
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FRR – Recovery Systems – 2 of 3
Recovery Systems
Avionics Bay and Recovery Components
Avionics Bay and Recovery Components
Redundant AltimetersDrogue Chute - Payload
Tube
Arming Switches Main Chute - Booster Tube
2 - Forward Eyebolts Main Shock Cord
2 - Aft Eyebolts Drogue Shock Cord
Batteries 4 - Quick Links
2 - Forward Charge cups Shock Cord 'Cradle'
2 - Aft Charge cups 4 - Black Powder Charges
GPS Recovery device Foil Frequency Barrier
Altitude Sensor for verification
Ejection charge terminals
We are using a dual event recovery system (DERS). The drogue parachute will be 28 inches in diameter, and will deploy at apogee. The main parachute will be 108 inches in diameter, and will deploy at 1100 feet. This will slow the descent rate to approximately 16.21 ft/sec.
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FRR – Recovery System – 3 of 3
Recovery SystemsEjection Charge Sizing
Shear Pins
Shear pins will be used to securely connect all sections that ejection charges will be separating. We will use 1/16” shear pins that require an average of 50 Lbs of force to shear. We are planning on using a minimum of 3 shear pins per section which will then require 150 Lbs. of force to shear, but additional testing is required to make sure this is suitable for the ejection charge sizes we have specified.
Shock Cord Cradle
To prevent a ‘zipper’ to the Booster tube when the Main chute deploys, the team has created a ‘Shock Cord Cradle’ that will reduce some of the stress created on the forward edge of the booster tube
Ejection Charge Sizes
Sub-System Charge Size (Grams) Shear Pin Size
Drogue Chute Ejection 1.5 gr. 1/16" Qty - 3
Main Chute Ejection 2.0 gr. 1/16" Qty - 4
Payload Release Mechanism 1.25 gr. 1/16"
Qty - 3
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FRR – Kinetic Energy
Kinetic Energy
Kinetic Energy Predictions (ft/lbs)
Altitude (10 mph winds)
Booster Tube (mass = 11.94 lbs)
Payload/AV Bay (mass = 3.55 lbs)
Payload (mass = 7.36 lbs)
Drogue Descent 767 ft/lbs 227 ft/lbs NA
Main Descent 48.77 ft/lbs 7.12 ft/lbs NA
Landing 48.77 ft/lbs 7.12 ft/lbs 55.77 ft/lbs
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FRR – Predicted Altitude and Wind Drift – 1 of 2
Launch Vehicle - Predicted Altitude and Wind Drift
Altitude Predictions
Wind (mph) Altitude
0 4489'
5 4479'
10 4444'
15 4385'
20 4303'
Launch Vehicle
Wind (mph) Range at Apogee
Range at Landing
0 0' 0'
5 -341' 311'
10 -653' 707'
15 -965' 1200'
20 -1257' 2020'
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FRR – Predicted Altitude and Wind Drift – 2 of 2
Payload – Range Predictions with Wind Drift
Payload (Separated at Apogee +- 4500')
Wind (mph) Range at Apogee Range at LandingAltitude
Deployment to Stay within 2500'
Range
0 0' 0' Apogee
5 -341' 1474' Apogee
10 -653' 2300' Apogee
15 -965' 3196' 3900'
20 -1257' 3630' 3400'
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FRR – Test Plans and Procedures – 1 of 2
Test Plans and Procedures
Test Procedures Status
Altimeter Deployment Test Altimeters are depressurized and then pressurized to test for proper ejection altitudes of the parachutes
Complete
Battery Connection Test The batteries are connected to the various subsystems to test for functionality
Complete
GPS Location Test (Astro) GPS is tested in various locations for verification of accuracy Complete
Altitude Test (Redundant Altimeter)
Redundant Altimeter unit is taken to various heights to test for accuracy
Complete
Ejection Charge Test Ejection charges are ignited in a safe environment to test for proper ejection
Complete
Ejection Test Elements of the launch vehicle are tethered to a zip-line. The ejection charges are then detonated to test for proper separation of elements.
Complete
RockSim Verification Test Data from subscale launch vehicle and from RockSim are compared to test the validity of RockSim
Complete
Altitude Test (Ejection Altimeters)
Altimeters are pressurized to various altitudes to test the accuracy of flight data
Complete
Subscale Launch Measurements of stability and strength were taken from the subscale flight to verify the integrity of the launch vehicle’s design
Complete
Parachute Drop Tests Both the drogue parachute and the main parachute are dropped from various heights to test for parachute functionality
Complete
Altimeter Continuity Test The continuity of the altimeter terminals are tested to verify proper wire connections
Complete
Integration Test The payload fits into the payload bay as designed Complete
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FRR – Tests and Procedures – 2 of 2
Test Plans and Procedures
Flight testing • Para-wing testing – concluded the design was too unstable – switching to
a round/vented parachute• Release mechanism
Static Line testing• Ejection charges• Shear pins• Recovery systems
Full-scale launch vehicle test flight(s)
• RC signal strength• Telemetry• Checklists• Component Integration
Additional Testing Completed since CDR:
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FRR – Additional Scale Model test flight
Additional Scale Model Test Flight
Launch Details Launch Date: February 28, 2012 Launch Location: Richard Bong State Park Launch Conditions:
• 52 degrees• partly cloudy• 5-10 mph from NW• launch at 11:45 AM CST
Launch Objectives and Results:• Retest DERS• Verify shear pins in actual
test flight.• Verify range of payload
electronics.• Checklist verification• All verifications successful.
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FRR – Full-Scale test flight - 1 of 4
Full-Scale Test Flight
Launch Details Launch Date: March 17, 2012Launch Location: Richard Bong State Recreation Area
• GPS coordinates: Lat: 42 Deg, 37 Min, 44.06 Sec N Long: 88 Deg, 10 Min, 17.83 Sec W
Launch Conditions:• 73 degrees• partly cloudy• 10-15 mph from NW• launch at 2:45 AM CST
Launch Objectives:
• Verify RockSim predictions
• Test a dual event recovery system with redundant altimeters.
• Use checklists for prep, launch, flight, recovery, and analysis.
• Verify payload integration
• Verify that our GPS system worked correctly.
• Determine if our construction techniques were suitable to meet SLI requirements.
• Collect data for analysis.
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FRR – Full-Scale test flight - 2 of 4
Full-Scale Test Flight
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FRR – Full-Scale Flight Test – 3 of 4
Full-Scale Test Flight
Flight and Recovery Observations:• Launch was straight and smooth with no
indications of any issues.• The nose cone ejected with the payload while
still climbing – at about 2823 feet.• This caused the drogue and payload chutes
to partially shred due to extreme wind force.• Main chute deployed as planned – at 1100’.• The payload chute acted like a streamer, and
only partially slowed the payload descent. This caused the payload to land with KE outside of guidelines.
• The LV landed within guidelines.
Data Analysis:• The dual deployment system worked as
designed.• We had good signal connection with the RC
components from the ground.• We were at a maximum of 3,027 feet from
transmitter to receiver.• Both altimeters worked for the redundant
charges.• The Garmin Astro worked perfectly, and gave us
accurate recovery data.
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FRR – Full-Scale Flight Test – 4 of 4
Scale Model Test Flight
On-board Altimeter Data
Data Analysis and Conclusions
By looking at the flight data and observations, the following conclusions can be made:
• Apogee was reached in 13.85 Sec.• Apogee altitude was approximately 2823 Ft.• RC Signal Strength was strong.• GPS was accurate• Flight was stable
The team believes that the nose cone ejected early due to an increase of pressure in the payload tube.
To keep this from happening again, the team has now added shear pins to the nose cone, and have also added larger vent holes in the payload tube.
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FRR – Recovery System Tests – 1 of 2
Recovery System Tests
Multiple tests and Verifications:
Static Line tests:
• Completed using an exact scale model of the actual LV system.• Verify ejection charge sizes• Verify shear pin size and placement• Verify recovery deployment and shock cord
Flight tests:
• 6 test flights for verifying the DERS• Some early failures that enabled the team to make modifications.
Release Mechanism for Payload:
• Added during CDR.• Tested and verified with static line testing and flight tests.
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FRR – Recovery System tests – 2 of 2
Recovery Systems
Avionics Bay and Recovery Components
Avionics Bay and Recovery Components
Redundant AltimetersDrogue Chute - Payload
Tube
Arming Switches Main Chute - Booster Tube
2 - Forward Eyebolts Main Shock Cord
2 - Aft Eyebolts Drogue Shock Cord
Batteries 4 - Quick Links
2 - Forward Charge cups Shock Cord 'Cradle'
2 - Aft Charge cups 4 - Black Powder Charges
GPS Recovery device Foil Frequency Barrier
Altitude Sensor for verification
Ejection charge terminals
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FRR – Summary of Requirement Verifications – LV
Summary of Verifications – Launch Vehicle
Requirement Design Element Verification5,280 feet AGL Motor K1050W Altitude will be under 5280’Maximum total impulse of 2,560 Nsec (K) Motor K1050W Aerotech testing resultsRemain subsonic Maximum Velocity = .504 mach RockSim and LV test 1All sections to have GPS tracking device Garmin Astro in payload and AV Bay Completed – flight testMust be have a stabilty margin of between 2.0 and 2.50 (RockSim)
Stability margin – 3.22 RockSim analysis and inspection
Must have at least 1 sub-scale test flight Scheduled for 1-14-2012 CompletedMust have at least 1 test flight of full-scale LV Scheduled for 3-17-2012 CompletedLV must meet flight review by RSO Pending approval Inspection by RSOReady to launch within 2 hours of waiver Pending test flights CompletedReady mode for one hour Electronics tested to achieve CompletedUtilize Launch and Safety checklist Completed - see PDR Inspection and analysisDERS - Drogue and Main chutes Completed in design Inspection and TestingSeparate Arming Switches - no higher than 6' Completed in design Inspection and testingRedundant Altimeter Systems Completed in design Completed
Electronics protected from freq. interferenceCompleted in design - a foil barrier on surface of forward bulkplate
Analysis and testing
Removable Shear pins Completed in design Included in design and testedNo more than 75 ft/lbs of KE per section Maximum KE = 55.77 ft/lbs RockSim analysis and LV Test
All sections within 2,500 feet of launch pad Chute size and deployment affect RockSim analysisUtilize Recovery checklist Completed - see FRR Inspection and AnalysisReady for re-launch in same day - no repairs Pending test flights TestingCollect experiment data for analysis Telemetry data being stored on laptop TestingMust have flown and recovered a min of 15 flights at K Class or greater
Both Mentors have achieved this Completed
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FRR – Payload Design – 1 of 6
Payload Design
Payload Objectives
• Direct the payload to a specific landing location• Gain telemetry from our payload such as speed, GPS coordinates, and altitude• Land the payload SAFELY• Gain video telemetry to accurately direct the payload Payload Success Criteria
To have a successful payload, our team has brainstormed a list of requirements that our payload shall meet. They are:
• Land the payload within 50 feet of a designated location• Land the payload SAFELY• Gaining information from the payload during the payload’s flight
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FRR – Payload Design – 2 of 6
Payload Design
Payload Systems:
• RC controlled fan – to provide the payload with controlled movement• RC controlled directional fins – to change the course of the payload• Video camera – to help the pilot guide the payload• Telemetry system – to help collect data to analysis the descent• GPS locator – to assist in the recovery of the payload should it go off course• Parachute – will use a ‘vented’ chute to provide flight stability.• Payload release mechanism – for safety – remotely controlled release of the payload when the RSO gives approval.
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FRR– Payload Design – 3 of 6
Payload Design – Fan and Directional Fins
Payload fan
Fan and Directional Fins
• The fan drives the payload forward.• It is controlled by the Payload Pilot using an RC transmitter.• The directional fins change the course of the payload.• They are also controlled from the ground by the Payload Pilot.• Combined, this system will enable the Payload Pilot to steer the payload to a desired landing zone.
Directional Fins
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FRR– Payload Design – 4 of 6
Payload Design – Electronics
Electronics Sled Payload Electronics:
• RC System – houses the RC receiver.• Controls the fan and directional fins• Transmits telemetry data.• Sends a live video feed so the Payload Pilot can see where the payload is going.• Activates the release mechanism.
Video Camera and Locator
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FRR – Payload Design – 5 of 6
Payload Design – Electrical Diagram
Electrical connections
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FRR – Payload Design – 6 of 6
Payload Design – Release Mechanism
Payload Release Mechanism
Release Mechanism:
• The release mechanism is a container holding the payload parachute, and keeps the entire payload attached to the LV by the drogue chute shock cord.• It remains this way until given permission by the RSO to release the payload.• When approved, the Payload Pilot will activate an RC controlled ejection charge that separate the release ‘cup’ from the payload.• The ‘cup’ will remain attached to the drogue chute shock cord for the descent.• Once released, the parachute for the payload will deploy.• The ejection charge contains 1.25 grams of black powder, which has been verified to be adequate to eject the release cup.
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FRR – LV Key Design Features
System Rationale Characteristics
A - Nose Cone Part of payload - needs to be durable Fiberglass with Ogive design
B - Payload Engineering experimentDesigned to hold all components, deploy easily, able to maneuver, and be durable.
C - Payload Tube Lightweight and durable 6" Carbon Fiber - fiberglass too heavy.
D - Avionics Bay Standard design for redundant ejection charges.Screws attach to payload tube, and shear pins to booster tube for ejection.
E - AV Bay CollarHolds the arming switches - can be easily armed from outside of LV.
2" collar is adequate for arming switches and for vent hole for altimeter.
F - Drogue ChuteDesign to eject with payload and allow LV to descend with wind.
28" Nylon chute that is attached with quick links to eyebolts in bulkplate on Avionics Bay.
G - Main Chute Slows the LV down to safe landing velocity.108" Nylon chute that deploys at 1,000' to reduce impact of winds.
H - Booster TubeNeeds to be lightweight and durable to resist zippers.
6" Carbon Fiber - fiberglass was too heavy for the motor requirement.
I - CradleDesigned to absorb some of the stress on tube from deployment of main.
Connects to the shock cord at the edge of the booster tube.
J - Motor Mount Standard motor mount system for 54 mm motor. Using a K1050W motor from Aerotech
K - FinsAttached to motor tube, and sized to provide stable flight.
Fiberglass fins provide durable system
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Launch Vehicle Key Design Features
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FRR – Payload Integration and Interfaces - 1 of 3
Payload Integration and Interfaces
Payload Integration:
• Payload Containment Tube is attached to the nose cone.
• The tube is divided into different levels, with each level holding payload components.
• GPS tracking unit• RC batteries and Servos• Telemetry components• Fan and directional fins• Wireless Video camera with
retractable arm• Parachute cup with release charge
• The Payload Containment Tube slides inside the payload airframe tube.
• At the end of the Payload Containment Tube is the Parachute cup, which also houses the Release Ejection Charge.
• The entire payload system is secured to the payload airframe tube at the nose cone with shear pins.
Payload Interfaces:
• RC Interface• Control of fan• Control of directional fins• Activate release ejection charge• Telemetry Interface
• GPS Interface• TeleMetrum
• Video Interface• To monitor on ground
AV Bay Interfaces:
• Altimeters• Redundant altimeters activate DERS
ejection charges
• GPS • Garmin Astro
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R/C Signal ComponentsComponent Function
HiTec Optic 2.4
Transmits the commands for moving the fins
and power to the fan
HiTec- Optima 9
Receives the fan and fin movement information from the tramsmitter
HiTec-HS-45HB
Moves the directional fins per
the signal received
Telemetry ComponentsComponent Function
TeleMetrum
transmits the telemetry data to the ground using
Radio signal.
TeleDongle
Receives the GPS signal from the payload, and
configures it into the laptop.
Additional Payload Components
Component Function
WiVid L-5801-BTransmits positioning video to Payload Pilot
Garmin Astro 220Assists in recovery of Payload - back up for
GPS data
E-Flite 300 EFLM1150
Adjustable speed fan for forward movement
E-Flite 300 EFLM1150
powers all of the R/C controls on the Payload
Horizon R/C landing gear
Moves the camera to the desired view point
for pilot control
LOC Precision / Custom-made
Custom vents to propel the Payload forward
Custom MadeAdjusts the air flow to turn the Payload on
descent
Payload Integration and Interfaces
FRR – Payload Integration and Interfaces - 2 of 3
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FRR – Payload Integration and Interfaces - 3 of 3
Payload Integration and Interfaces
Component Frequencies
Component Location Frequency Wattage Range
HiTec Optic 2.4 Payload 2.4 GHz 390 mA 1 Mile
RC Optima 9 Payload 2.4 GHz AFHSS 325 mA 1 Mile
WiVid L-5801-B Payload 5.8 GHz 500 mW 2 Miles
Telemetrum Payload300-348 MHz 391-464 MHz 782-928 MHz
25 mA 1 Mile
Garmin Astro DC 40 AV Bay 5 Miles
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FRR – Summary of Verifications – Payload
Test Procedures StatusDrop Test The vented chute will be tested from 250’ for flight stability
and responsiveness to pilot commands.Planned
Battery Connection Test The batteries are connected to the various subsystems to test for functionality
Complete
GPS Location Test (GPS Unit) GPS is tested in various locations for verification of accuracy
Complete
Altitude Test (GPS Unit) GPS unit is taken to various heights to test for accuracy Complete
Speed Test (GPS Unit) GPS unit is moved at various speeds for verification of accuracy
Complete
Flight Path Test (GPS Unit) GPS unit’s flight path is tested during the drop test to verify accuracy
Complete
GPS Location Test (Garmin Astro)
GPS is tested in various locations for verification of accuracy
Complete
Altitude Test (Altimeter) Altimeter is taken to various heights to test for accuracy Complete
R/C Transmitter and Receiver Operating Distance Test
R/C Transmitter and Receiver are taken to their furthest operating distance to verify that the will operate at over 1 mile
Complete
Thrust Test The payload is placed on a scale and has its thrust steadily increased to verify that it can propel the payload in flight
Complete
Wiring Test The subsystems are connected to corresponding wire connections to test if each responds accordingly
Complete
Stress Test The payload is run for an hour to verify that it can withstand the stresses of flight
Complete
Camera Test Camera images are compared to known ground features to ensure that the camera is functioning
Complete
Final Test The completed payload is tested for functionality Planned
Summary of Verifications - Payload
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FRR – CDR Feedback Items
CDR Feedback Items
Feedback Items and Resolution:
• Calculate the KE for each section of the vehicle.
• Added to the FRR and also the Milestone Fly Sheet.
• Describe the release mechanism in greater detail.
• Added to the FRR and also added to this presentation.
• Ensure that the main does not deploy at apogee ejection event.
• The team has tested and verified that the shear pins will hold the main in place until the ejection event for the main occurs.
• Describe the algorithm that controls the UAV
• Our UAV is controlled remotely from the ground through an RC controller.
• How far will the UAV drift in a 20 mph wind from its ideal release point.
• The team has decided to alter the design by using a standard round but vented parachute. This will significantly reduce any chance of the payload landing outside the 2500’ perimeter. In addition, to reduce this landing range, the team calculated that in a 20 mph wind, the payload should not be released until 3400 feet.
• Describe the mechanism that turns the UAV.
• More information was added to the FRR, and also this presentation, regarding the entire payload fan and directional fin system. The team is still testing the deflection of the fins to determine how much force is created.
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Thank you!
Can we answer any of your questions?