CDR template revised Ver 3.1.1 presentation
Transcript of CDR template revised Ver 3.1.1 presentation
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Team BExplorer
MACE35120 CDR Outline Version 3.1.1
MACE31520 Design 3 CDR: Team B (Explorer)
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Presentation Outline
Presenter: Arya Dash MACE31520 Design 3 CDR: Team B (Explorer)
1. Introduction – Arya Dash1.1 Presentation Outline………………………………………………….2
2. Systems Overview – Arya Dash2.1 Mission Summary……………………………………………….……..102.2 System Requirement Summary………………………………….…..112.3 System Level Configuration Trade & Selection……………………12 2.4 System Concept of Operations………………………………...……14 2.5 Physical Layout………………………………………………………..162.6 Balloon Compatibility…………………………………………...……..21
3. Sensor Subsystem Design – Arya Dash3.1 Sensor Subsystem Overview…………………………………………24
3MACE31520 Design 3 CDR: Team B (Explorer)
4. Descent Control Design – Arya Dash4.1 Descent Control Overview………………………………………….274.2 Descent Rate Estimates……………………………………………294.3 Safety Case………………………………………………………….30
5. Structural Subsystem Design – Arya Dash5.1 Structural Subsystem Overview……………………………………325.2 Mass Budget…………………………………………………………41
Presenter: Arya Dash
4MACE31520 Design 3 CDR: Team B (Explorer)
6. Communications & Data Handling Subsystem Design –Siddharth Mundeja6.1 CDH Overview……………………………………………………….436.2 Frequency Selection……………………...………………………...466.3 Antenna Trade & Selections ………………………………………476.4 Antenna Choice……………..………………………………………496.5 Radio Configuration…………………………………………………50
7. Electrical Power Subsystem Design – Siddharth Mundeja7.1 EPS Overview………………………………………………………..537.2 Electrical Block Diagram…………………………………....………58
Presenter: Arya Dash
5MACE31520 Design 3 CDR: Team B (Explorer)
8. Flight Software Design- Bagrat Rashoyan8.1 FSW Overview……………………………………………………………….648.2 FSW Architecture…………………………………....................................658.3 System FSW State Diagram…………………………………….………….68
9. Ground Control System Design – Bagrat Rashoyan9.1 GCS Overview…………………………………………………….………….709.2 GCS Antenna System……………………………………………….……....729.3 Antenna Distance Link…………………………………………….…………739.4 GCS Software……………………………………………………….………..74
10. System Integration and Test – Stephen Choi10.1 System Integration and Test Overview……………………….….……….76
12. Management – Stephen Choi12.1 System Budget…………………………………………………….....……..10012.2 Conclusions……………………………………………………….…………112
Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 9
Systems Overview
Arya Dash
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Mission Summary
Presenter: Arya Dash MACE31520 Design 3 CDR: Team B (Explorer)
Mission Objectives: Primary Rationale: System must measure oxygen level: Data can be
used for biological studies of phenomena such as ‘hypoxia’ and ‘cyanosis’ or ‘altitude’ training of athletes
Auxiliary:• Safety first!!• System must satisfy CAA Small Balloon Requirements- All up system
below 2m
System Requirement Summary
11MACE31520 Design 3 CDR: Team B (Explorer)Presenter: Arya Dash
MAJOR ITEMS OF NON-COMPLIANCE: Altitude of 7500 m as opposed to 9100 m.
Rationale: Biological studies are of interest in the lower atmosphereBenefits:– Better Ascent performance: reduced ‘Lift’ requirements– Enhanced Power Consumption: Reduced flight time– Improved Sensor Performance: Warmer temperatures– Better T/W Ratio
Solar Sensor Oxygen Sensor No Back Up Power Source
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System Level Configuration Trade & Selection
MACE31520 Design 3 CDR: Team B (Explorer)Presenter: Arya Dash
• MECHANICAL SUBSYSTEM changes since PDR:
PDR LEVEL:• Did not conform with the CAA
Small Balloon Requirements• Unsafe and unreliable: Hook
interfaces
CDR LEVEL:• Fully conforms with CAA Small
balloon Requirements• Improved Reliability: Knots and
fewer interface connections
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System Level Configuration Trade & Selection
ELECTRONIC SUBSYSTEM: Selection of Components and Tradeoff
Component PDR Selection
Major Reasons CDR Selection
Advantages Trade-off
Microcontroller Arduino Due
Compatibility issues with GSM and Oxygen Sensors
Link-it one • Integrated GSM • Oxygen
Sensor-‘Easy to integrate’
Power
GPS ADAFRUIT Poor Compatibility with Link-it One
MediaTech MT3332
Highly compatible Placement Flexibility (Short wire length)
Arrangement of temperature sensor and altimeter
On side surfaces
• Cross winds• Entangling
issues
At the bottom protected by a grove
• No interference from cross winds and mainstream flow
• No tangling issues
Manufacturing
Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 14
System Concept of Operations
Presenter: Arya Dash
• Launch and Descent
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Ground Station
Launch,GSM not activated
Balloon Burst
>7500m Parachute Deployment
GSM activated,Payload
Touchdown,System
recovery.
Sensors record data, data
stored in SD card,
Telemetry packet transmit data to Ground
Station
Physical Layout
Ascent Mode: Descent Mode:
16Presenter: Arya Dash MACE31520 Design 3 CDR: Team B (Explorer)
18MACE31520 Design 3 CDR: Team B (Explorer)
Physical Layout
Presenter: Arya Dash
Placement of major components:
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Physical Layout
Presenter: Arya Dash
Placement of major components:
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Balloon Compatibility
MACE31520 Design 3 CDR: Team B (Explorer)Presenter: Arya Dash
Balloon Payload Compatibility Analysis using Non-Dimensional Studies:• Key Parameter for aerodynamic performance: T/W Ratio• Min. T/W requirement is also influenced by required ‘ascent rate’
Balloon Compatibility
22Presenter: Arya Dash MACE31520 Design 3 CDR: Team B (Explorer)
Physics
Lift due to buoyancy
Mass of (payload+balloon) x g
Drag
Force due to buoyancyM- Total massg- Acceleration due to gravity- Force due to drag- Density of Helium v-velocity of system
S- cross section area of balloon
MACE31520 Design 3 CDR: Team B (Explorer) 23
Sensor Subsystem Design
Arya Dash
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Sensor Subsystem Overview
Presenter: Arya Dash MACE31520 Design 3 CDR: Team B (Explorer)
GPSModel No: MT3332
This sensor will be used to get values for latitude, longitude and altitude
Grove Gas Oxygen Sensor
Model No: O2This Sensor is used to calculate main sensor subsystem requirement, that is oxygen.
Temperature SensorModel No: DS18B20
The System will use this sensor in order to measure internal temperature.
Voltage SensorModel :Micro HKPilot Mega
PDBThis Sensor is used to take voltage reading for battery throughout the flight. .
AltimeterModel No: BMP180
Our System uses this sensor to get values for altitude, external temperature and pressure.
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Descent Control Design
Arya Dash
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Descent Rate Estimates
20 40 60 80 100
120
0
4
8
12
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Descent velocity Vs. Parachute Diameter
Descent velocity (m/s)
Diameter (cm)
Desc
ent V
eloc
ity (m
/s)
Ideal Range
Design Point
• Partial deployment of parachute reduces projected surface area and drag coefficient due to shape deformation i.e. Cd*S reduces.
Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 30
Safety Case
4.47
4.71
5.00
5.34
5.77
6.32
7.07
8.16
9.99
11.30
12.00
05
1015202530354045
Kinetic energy Vs. Impact velocity
Kinetic energyThreshold
Impact velocity (m/s)
Kine
tic e
nerg
y (J
)
34J
40J
• According to the the document produced by Monash University, ‘Human injury model for small unmanned aircraft impacts,2013’ kinetic energy for impact above 40 J is considered dangerous to humans.
• Max attainable kinetic energy is 34 Joules at all measure of undeployed parachute which is below the threshold kinetic energy of 40 J.
Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 31
Mechanical Subsystem Design
Arya Dash
Mechanical Subsystem overview
Structure A newly designed light weight case to house the sensors and other electrical components
Material Built from polystyrene foam blocks.
Assembly The structure is easily assembled from 2 main sections; the main housing part and the lid.
Interface The parachute is secured to the payload box with a mounting plate. The Balloon is connected to the payload by a cable that goes through a hole at the top of the parachute and the mounting plates.
32MACE31520 Design 3 CDR: Team B (Explorer)Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 41
Mass Budget
483 g, 96.6%
17 g, 3.4%
All Up Mass
Measured Margin
All Up Mass 483 gramsMax. Allowed 500 grams
Presenter: Arya Dash
MACE31520 Design 3 CDR: Team B (Explorer) 42
Communication and Data Handling (CDH) Subsystem Design
Siddharth Mundeja
MACE31520 Design 3 CDR: Team B (Explorer) 43
CDH Overview
Presenter: Siddharth Mundeja
LinkIt-One [with integrated GSM & GPS]
3DR Transceiver
433 Mhz Yagi Antenna
Connected via Tx & Rx Pin
Connected via SMA Connector using adapter
Connected via USB
Sends a text with GPS data when below 1000m
3DR Transceiver
Ground Station Computer [with GCS Software]
Data From Sensors
• Continuous data transmission
• 10mW• 100% duty cycle• 434.20 MHz • 25 kHz channel
Ground Control System
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CDH Requirements
433.05
434.2 434.79
100% 1 mW; no channeling
100% 10 mW; 25kHz channels
10% 10 mW; no channeling
Ofcom specifications for 433 MHz unlicensed Short Range Devices (SDRs)Legal Requirements.
Selected
Presenter: Siddharth Mundeja
• ~ 800 bits per second• Low power consumption
• Omnidirectional Transmission• Low power consumption
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Antenna Trade & Selection
Trade Parameters Monopole Antenna Loop Antenna Helical Antenna
Criteria (Weightings %) Score
Weighted Score
Score
Weighted Score
Score
Weighted Score
Range (50) 9 4.5 6 3 3 1.5
Ease of De-tuning (5) 9 0.45 5 0.25 3 0.15
Gain (5) 8 0.4 5 0.25 5 0.25
Size (10) 9 0.9 4 0.4 2 0.2
Weight (20) 9 1.8 6 1.2 3 0.6
Cost (10) 7 0.7 9 0.9 5 0.5
Total Weighted Score 8.75 6 3.2
Selected Antenna: Monopole Antenna • Best range• The whip antenna mitigates a mechanical construction that the helical antenna
and the loop antenna offers.• With the sacrifice of cost, the best performance is delivered.
Higher is better
Presenter: Siddharth Mundeja
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Antenna Choice
• Quarter wave Monopole Antenna
• Vertically Polarised
• 2dBi gain
Radiation Pattern: Doughnut Shaped
3DR Radio with Antenna
Remote module Antenna
Presenter: Siddharth Mundeja
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Radio Configuration
• 3DR Digital telemetry radio
• Custom data packet
Presenter: Siddharth Mundeja
• Radio configuration (NETID, baud, etc.) set via “Mission Planner” GUI”
• Configuring Net ID for pairing and ensuring not receiving alien data
• Setting min max frequency for spectrum hoping(within license free zone)
MACE31520 Design 3 CDR: Team B (Explorer) 52
Electrical Power Subsystem (EPS) Design
Siddharth Mundeja
MACE31520 Design 3 CDR: Team B (Explorer) 53
EPS Overview
Made by: Ola Majasan
Component Diagram
• Battery: 3 x Varta (1x1.2V) 500mAh NiMH Rechargeable Coin Cell Battery
Microcontroller• Acts as a node.• Distributes current
to sensors & Radio
Micro HKPilot Mega PDB• Measures the
Voltage across the battery. Value reported to GCS.
Sensor and Radio
• Sensors 3.3 V• Radio 5.0 V
Main Supply Battery (3.6 V)
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Electrical Block Diagram
Battery
Radio Module, Supply with 5 V
Altimeter, Supply with 3.3V
Oxygen Sensor, Supply with 5V
Grey Arrows : These indicate the direction of flow of information throughout the circuit.
Blue Arrows : These indicate the direction of flow of power throughout the circuit.
Temperature Sensor, Supply with 3.3V
Current/Voltage Sensor
MACE31520 Design 3 CDR: Team B (Explorer)
GPS antenna, Supply with 3.3V
Made by: Ola Majasan
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Flight Software (FSW) Design
Bagrat Rashoyan
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FSW Overview
Initialising Sensors(at start/reboot)
Loop: Data acquisition
(2 second sleep)
Transmit Store
Data Flow• Programming language – C/C++ with wrappers
• MCU Operating System – None
• Programming Environment – Arduino
• Using libraries supplied by sensor vendors
• Data stored on SD card
• Consumes an average of 115 mAh (90 when at sleep, 140 when transmitting) available 500 mAh [Voltmeter tested]
Presenter: Bagrat Rashoyan
FSW Architecture
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ARCHITECTURE
SENSORS
MCU
DATA LOGGINGRADIO
DATA RECEIVEDDATA TRANSMIT
GSM MODULE
Presenter: Bagrat Rashoyan
Declare variables Setup(){ Initialize sensors}
Loop(){ Get Senor Data Transmit Store Sleep for 2 seconds}
"#,teamID,packetNo,packetTime,lat,lon,alt,satNo,baroH,press,extTemp,intTemp,vol,MD5"
MACE31520 Design 3 CDR: Team B (Explorer) 69
Ground Control System (GCS) Design
Bagrat Rashoyan
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GCS Overview
LinkIt-One [with integrated GSM & GPS]
3DR Transceiver
433 Mhz Yagi Antenna
Connected via Tx & Rx Pin
Connected via SMA Connector using adapter
Connected via USB
Sends a text with GPS data when below 1000m
3DR Transceiver
Ground Station Computer [with GCS Software]
Data From Sensors
• Continuous data transmission
• 10mW• 100% duty cycle• 434.40 MHz • 25 kHz channel
Ground Control System
Presenter: Bagrat Rashoyan MACE31520 Design 3 CDR: Team B (Explorer)
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GCS Antenna System
Presenter: Kelvin Kan 72
Radius =1 meter
Antenna in clear line of Sight of the remote module manually adjusted to pint towards the module continuously.
Antenna 1 m clear of any objects to prevent signal bouncing.
Lightening arrestor to protect the system and operator
2 m
Masted 2m above the ground on a non-conducting mast
Antenna set at the highest possible position at the launch site.
MACE31520 Design 3 CDR: Team B (Explorer)Presenter: Bagrat Rashoyan
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Antenna Distance Link
The following equation gives a theoretical range of the yagi antenna communicating with the system monopole antenna.
R = Transmission Distance in kmf = FrequencyPt= is the Tx power for the device that will be transmitting data Gt= is the Tx antenna gain, the antenna gain of the antenna on the transmitting device.Pr= is the Rx sensitivity of the device receiving data.Gr= is the Rx antenna gain, the antenna gain of the antenna on the receiving device.c = speed of light
Tx power = 10 dBmTx antenna gain = 3.3 dBi
Rx sensitivity = -118 dBmRx antenna gain = 13 dBi
Frequency = 434.2 MHz The distance link is estimated to be 20.8 km
𝑹=√ 𝑷𝑻 𝑮𝑻 𝑮𝑹𝒄𝟐
𝑷𝑹× 𝟏𝟒𝝅 𝒇
Presenter: Bagrat Rashoyan
GCS Software
• Custom GUI software designed Using Qt Creator (C++)• Data received from 3DR radio through USB com port, parsed and
displayed on relevant LCDs
MACE31520 Design 3 CDR: Team B (Explorer) 74Presenter: Bagrat Rashoyan
MACE31520 Design 3 CDR: Team B (Explorer) 75
System Integration and Test
Stephen Choi
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System Integration and Test Overview
Presenter: Stephen Choi
Test Title Purpose Test Set up Test Inputs
Successful criteria
Predicted Result and
basis
Recorded Result
Actions Required Order
Mechanical SubsystemPayload box drop test
Survivability of structure and components are protected during impact.
Container with all components mounted in the container and suspended from high ledge
Release of container
• Accelerating force inside the container are not too large
• Visual inspection of acceptable damage
All components remain in working condition after impact.
Structure remain intact and electric components remained functional
• Additional Shock absorbing padding
1
Parachute deployment test
Successful deployment of decent control mechanism during freefall
Parachute and container assembled in decent configuration.
Release of container with parachute
• Successful deployment of parachute
Successful deployment of parachute
N/A • Alternate nylon cables and pre-prepped loops
• Pre-manufactured parachute
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Knot Connections
Ensure Knots do not come undone or cut during operation
Using a force meter pull one end of the cable and secure the other end using knot.
Increase force on cables
• Retained integrity of knots
Knots will be intact
N/A 2
MACE31520 Design 3 CDR: Team B (Explorer) 77
System Integration and Test Overview
Test Title Purpose Test Set up Test Inputs Successful criteria
Predicted Result and
basis
Recorded Result
Actions Required
Order
Electrical SubsystemElectrical Connection test
Integrity of electrical connections after soldering and placement
Electrical components soldered
Multimeter testing
• Voltage across components
• No noise
Voltage and current readings shows a closed circuit
All electrical components were connected
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Battery Endurance Test
Show the available run time of the power pack
Connect all electrical components and leave the system to operate for a specified period.
Timer • Can at least power system for four hours
System can operate for over four hours
Total Run-time: 6 hours
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Cold Temperature Tests
Effects of temperature on the electrical components
Payload box with electrical components connected
Cold box to create environment
• Electronics still functional and report sensible values
Electronics still functions as intended
Tested for -20 degrees
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Presenter: Stephen Choi
MACE31520 Design 3 CDR: Team B (Explorer) 78
System Integration and Test Overview
Test Title Purpose Test Set up Test Inputs Successful criteria
Predicted Result and
basis
Recorded Result
Actions Required
Order
CDH SubsystemRadio Reliability Test in Urban Environment
Radio and Antenna communic-ation reliability
GCS and completed payload box set at >1km apart
GCS and CDH software
Continues to communicate and receive data >1km
Successful communication with some interruptions
Successful communi-cation with some interference
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Data Storage Test all required data can be reliably stored on microSD card
Insert microSD into LinkIt One and start sensor recordings
Non-corrupt data could be retrieved from microSD
Useful data could be obtained
No issues encountered
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Presenter: Stephen Choi
MACE31520 Design 3 CDR: Team B (Explorer) 81
Mission Operations & Analysis
Stephen Choi
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Management
Stephen Choi
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System Budget – Other Costs
Presenter: Stephen Choi
Components Model Quantity Cost (£) Price Definition
Battery Varta 3.6V NiMH coin cell
1 4.90 Actual
Microprocessor Arduino Due 1 34.27 Actual
Temperature sensor DS18B20 1 3.93 Actual
Mounting plate 4MP1212 2 16.14 Actual
Parachute - - 1 3.00 Budgeted
Polystyrene Box - - 2 5.00 Budgeted
Subtotal 67.24
Prototype & Testing
LabourComponents Model Quantity Cost (£) Price Definition
Human labour Undergraduate 1200 hours 18000 Approximation
Subtotal 18000
MACE31520 Design 3 CDR: Team B (Explorer)
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System Budget – Total Cost
Presenter: Stephen Choi
Budget Type Sub-total Cost (£)
Sensor Subsystem 83.88
Electrical Power Subsystem 27.13
Communications and Data Handling Subsystem 140.41
Structural 30.50
Ground Control System 172.36
Prototype & Testing 67.24
Overall Total 521.52
MACE31520 Design 3 CDR: Team B (Explorer)
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Conclusions
Presenter: Stephen Choi
Major accomplishments:• Re-designed system to comply with CAA small balloon requirement• Reduced weight to below 500g• Sensors are working• Communications are working• Mitigation by producing our own payload box and parachute• Launch day schedule and operations manual• Budget estimated
Major unfinished work:• Oxygen sensors need to be purchased• Solar panel needs to be purchased• Oxygen and solar flux sensors need to be programmed and calibrated• Some tests to be carried out
Why we are ready to proceed to flight readiness review:• System is designed and built, with tests done showing a good performance
and compliance to most requirements. Non-compliances are explained.