asteroid sample return aem 4332 final design review 5/7/2008 becky wacker carla bodensteiner ashley...
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Asteroid Sample Return
AEM 4332Final Design Review
5/7/2008•Becky Wacker•Carla Bodensteiner•Ashley Chipman•John Edquist •Paul Krueger•Jessica Lattimer•Nick Meinhardt•Derek Steffes•Sam Zarovy
1
Becky Wacker
Team OverviewAttachment Method
2
Mission GoalDrill into the asteroid and return 100 g core sample
from a depth of 1 meter for study on Earth.
3
Our Mission Objectives
1. Leave orbit about the asteroid and position for landing
2. Land on the asteroid with drill and return vehicle intact
3. Attach the spacecraft to the asteroid for 24 hours withstanding a 10 N reaction force and a 0.1 N/m torque from the drill
4
Requirements• Spacecraft must weigh no more than 750kg including:
– 50kg payload package (drill and stereo cameras)– 200kg return vehicle
• The spacecraft must land and support drilling operations for 24 hours
• Landing must not exceed 15 g’s
• Spacecraft must support drilling operations:– 10 N reaction force– 0.1 N/m torque
5
Expectations• Explain the results of all system and hardware trade studies including
rationale for final selections
• Provide spacecraft layout drawing(s)
• Demonstrate compliance with all requirements
• Provide high-level block diagram of the spacecraft subsystems
• Define system and hardware requirements sufficiently to allow future subsystem architecture definition and hardware trade studies
• Demonstrate that the landing loads do not exceed requirements and can be supported by the structural/mechanical configuration
6
Assumptions• Orbiter will supply pictures of asteroid to give targeted landing area• Asteroid is only gravitational pull in area• Orbiter can place lander in preferred initial placement• Major Tasks 1 and 2 are most important• Key asteroid physical properties
a. Rotation period is 5.0 hoursb. Semimajor axis: 1.5 AUc. Radius: 10 km (assume spherical shape)d. Mass is 1x1016 kge. Surface rock distribution is Gaussian with 0.25% probability of a 0.5
m rock in a 5 m2 area. f. Surface gravity: 0.006 m/s2
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Major Tasks1) Perform a trade study of approach, landing and anchoring options
which considers:
a. Control system architectureb. Structural impact loadsc. Anchoring mechanismd. Propulsion system options
2) Develop a spacecraft layout includinga. Mechanical/structural configurationb. GN&C sensor locations and field-of-view (FOV) clearancesc. Location and orientations of reaction control system thrustersd. Telecommunication component locations including antenna FOV clearances
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Major Tasks Continued3) Identify major hardware components of each spacecraft subsystem
a. Guidance, Navigation, and Controlb. Command and Data Handlingc. Electrical Powerd. Telecommunicationse. Propulsionf. Structures and mechanismsg. Thermal control system
4) Define the key system and hardware requirements5) Determine landing loads and associated structure/absorber sizing
9
Team Organization
C a rla B o de n s te in er
D e rek S te ffes
P a u l K rue g er
Jo h n E dq u ist
S tru c tu re s + M e cha n ism s
Je ss ica L a tt im er
S a m Za ro vy
N ick M e in h a rd t
A sh ley C h ip m an
G N & C + P ro p u ls ion
B e cky W a cker
10
Structures Group Responsibilities
• Design Structure to hold all components and protect payload package and return vehicle
• Perform ANSYS analysis on structural components to ensure structural stability
• Provide solution for thermal control needs• Determine attachment method and prove
effectiveness• Determine Center of Mass of spacecraft
11
GN&C and Propulsion
• Determine proper trajectory for mission• Complete trade studies for GN&C components• Develop high level block diagrams for GN&C
systems• Provide necessary propulsion system to satisfy
mission requirements• Provide solution for telecommunication needs
12
Project Summary
• Approach asteroid from orbiter using a Hohmmann transfer and descend from 500m altitude
• Use pressure regulated tank with monoprop clusters
• Use spikes post-impact to attach to asteroid surface
13
Layout
14
Attachment Method
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Initial Trade StudyIdea How works Pros Cons
Spikes on Impact
Drive stakes in when land from legs
Don’t need separate propulsion system (less weight)Highest probability for success
Harpoon Shoot something out and reel ourselves in
Uses more fuelMany mechanisms involvedPossibly get tangled to roll back up.
ThrustersPropulsion Only
Use thrusters to hold in place
Extra fuelTorque when drilling
Cork Screw Screws into ground like a cork screw into a cork
Not a high resulting force Complicated mechanisms and possibility of stirring soil instead of screwing in
Spikes Post-Impact
Two arms with small explosion that would rotate and come back while nailing into the ground
Would work…kind ofAble to retry
Even more complicated than harpoon
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Initial Trade Study Cont.Thrusters Harpoon Spikes on
ImpactSpikes Post-Impact
Corkscrew
Weight Bad Bad Good Okay Bad
MechanicalComplexity
Good Bad Good Okay Bad
FuelConsumption
Bad Good Good Okay Good
Power Requirements
Good Bad Good Good Bad
Dependability Good Bad Okay Good Bad
Applied Loads
Good Good Bad Okay Good
Reusability Good Bad Bad Okay Okay
17
Attachment Method Results
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Spikes Post-Impact Thruster Attachment
Mechanical Mass 8 kg (approx) 0kg
Fuel Mass 1.198 kg 590.4 kg
Total Mass 9.198 kg 590.4 kg
Attachment Method Overview• Assume built weight for guns to be same as hilti gun
(2kg ea.)• Use F=m(v/t) to determine force from anchor
deployment• t is assumed to be 0.01 s• Deploy two anchors simultaneously at 45° to reduce
thruster requirements• Determine required Thrust and Fuel based on Force• Assume 30s to deploy all 4 anchors• Use Anchor based on future research
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Gun• Use Mechanical fastening
system based on Hilti Gun model DX E72
• .22 caliber powder actuated fastening tool
• Drives up to 7.1cm nails into concrete or steel
• 2 kg each
http://www.us.hilti.com/holus/modules/prcat/prca_navigation.jsp?OID=-16951
20
Reaction Force
Ballistics information found at: http://www.korabrno.cz/bal-22.htmlUsed: Remington .22 Short CB Cap
• Bullet Weight = 1.87 g• Velocity = 213.36 m/s• Force from Attachment =
(213.36/.01)*(1.87/1000)=39.898N per anchor
21
Spike deployment requires a 21 N force from the 4 thrusters pointing in the +Z direction using a safety factor of 1.5
(56/4=14*1.5(safety factor)=21N/per thruster)
Reaction Force Continued
SpacecraftSpacecraft
+28N+28N+28N+28N
-28N-28N+28N+28N
Gun #1Gun #1Gun #2Gun #2
22
Future Work
• Make gun space worthy-space worthy construction material
• Test force required to insert nails-soil testing experiments
• Determine spike specifications-force experiments
23
Structures and Mechanisms
Paul KruegerJohn EdquistDerek Steffes
Carla Bodensteiner24
Paul Krueger
Spike ExperimentPackaging
25
Force Required to hold Spacecraft
2
2
515
0.006 /
10
1.5
4 spikes
1.5 10 515 0.006 / 2.59
4 spikes
sc
ast
dri
dri sc astfoot
m kg
g m s
F N
n
s
n F m gF
s
N kg m sN
26
Shear Force on Spikes
1 4
2 3
1 1 2 2
1 4
2 3
1.346
2.358
0.1
1.5
2 2
0.018
0.010
sc
sc
R R m
R R m
N m
n
F R F R
F F N
F F N
27
Spike Force Experiment
• Force spike can withstand anchored in ground?
• Driven in at 45 degree angle
• 45 L x 3 D mm spike– 3.6 N normal force– 4.3 N shear force– Within Hilti gun driving
capacity
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Spacecraft Frame
• Basic truss properties• Opening for return
vehicle and drill• Octagonal Shape• Dimensions based on
interior components– Each side 1m x 2m
• Constructed of aluminum and aluminum honeycomb panels
29
Packaging Trade StudyIdea How works Pros Cons
Dual Shear Plate Mounts electronics on flat plates that are mounted to shear plates that are then bolted to frame
Strong structure,Efficient packaging,Good heat dissipation
Needs custom electronics,Expensive
Shelf Shelf inside spacecraft where electronics are mounted
Uses standard electronics,
Inefficient packaging,Complicated heat dissipation
Skin Panel/Frame Electronics mounted to panels that are mounted to frame
Uses standard electronics,Good heat dissipation,Easy access
Less rigid than Dual Shear Plate configuration
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Packaging Trade StudyDual Shear Plate Shelf Skin
Panel/Frame
Structure Strength
High Low Medium
Heat-transfer Good Okay Good
Volume needed Small Medium Small
Needs custom electronics
Yes No No
Cost High Low Low
31
Future Work
• Build basic mock up of feet• Add mounting brackets to frame
– Return vehicle, drill, fuel tank, etc
• Lighten spacecraft frame
32
John Edquist
Landing Gear
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Landing Gear
• Basic Truss– Solid bar, D=20mm
• Low gravity allows smaller structure
• Multiple designs– ANSYS prevented
further testing
Landing Gear Ratcheting System• Gear is spring loaded• Must prevent it from bouncing off asteroid• Stopper prevents craft from bottoming out
Ratchet Spring Calculations• Total mass of craft: 519 kg• Force from gravity = Mass*Gravity
= 1.5*519 * 0.006 m/s2 = 5 N• Force on impact: F=SF*Mass*Velocity/Δt
=1.5*(519 kg)*(2.45 m/s)/(1 sec) = 1912 N• Force per pad = (1912+5)/4 = 479.25 N• Force from weight negligible due to very low gravity• Spring constant k=Force*Distance/Δθ
= (479.3 N)*(0.385 m)/(π/6 Rad) = 352 N*m/rad (per pad)= 6.2 N*m/degree (Δθ=30⁰)
Divide by 4 because 4 springs in parallel per pad:Individual spring constant: 1.5 N*m/degree
Source: http://en.wikipedia.org/wiki/Torsion_spring
Recommendations
• Optimize landing gear to reduce weight and areas of high stress concentration
• Continue design of ratchet system and work with Derek to perform ANSYS testing
• Perform more detailed analysis of internal components and structure for the SolidWorks model
Derek Steffes
Structural Impact LoadsMass Budget
38
Structural Impact Loads
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Structural Shape
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Mass Budget• From Design
– GN&C: 21 kg– Propulsion: 26.8 kg– Telecommunication: 10 kg– Structure: 110.4 kg– Thermal protection: 18.4 kg– Attachment guns/spikes: 8 kg– Propellant: 4.4 kg
• Given– Drill: 50 kg– Return vehicle: 200 kg
• Allocated– Electrical: 50 kg– Data handling: 20 kg
Total mass: 519 kgMass margin: 231 kg
41
Center of Mass
42
Structural Analysis• Material Type
– Aluminum Alloy 6061-T6• Source: Alcoa Engineered Products
– Aluminum Honeycomb Paneling 3003• Source: Portafab
• FEA element type– 10-node tetragon
43
Structural Analysis• Impact Load
– Linear momentum-Impulse• mvi+(FImp/SF)Δt=mvf
– Gravitational Force• Fg = SF(mg)
– Total impact load• F = Fimp + Fg
• Valuesm = 519 kgvi = 2.45 m/s
vf = 0 m/s
SF = 1.5Δt = 1.0 sg = -0.006 m/s2
FImp= -1907 N
Fg = -5 N
F = -1912 N44
Landing Assembly (Stress)
45
Landing Assembly (Stress)
46
Landing Assembly (Strain)
47
Landing Assembly (Strain)
48
Octagonal Structure (Stress)
49
Octagonal Structure (Stress)
50
Octagonal Structure (Strain)
51
Octagonal Structure (Strain)
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Hilti Gun Recoil (Stress)
53
Hilti Gun Recoil (Stress)
54
Hilti Gun Recoil (Strain)
55
Hilti Gun Recoil (Strain)
56
Future Work
• Single-structure analysis– Requires 256,000+ elements
• Dynamic load analysis• Spring-Ratchet system analysis• Non-ideal landing conditions analysis
– Single landing assembly impact
57
Carla Bodensteiner
Thermal Control
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Requirements
• Define high level diagram of thermal control• Identify major components required• Define system and hardware requirements
sufficiently to allow future thermal control architecture definition and hardware trade studies
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• Passive Thermal Control– Multilayer Insulation (MLI)– Surface Finishes
• Active Thermal Control– Panel (strip) heaters
• Closed switch controlled by PRTs (Platinum Resistance Thermometers) monitoring optimal temperature for spacecraft components
• Used to heat hydrazine thrusters before initial burns
Basic Hardware Required
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Active Thermal Control
Electronics and Thrusters
PRT monitor equipment
Command and Data Handling
Panel Heating ON/OFF
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Plume Protection
62
Plume Protection Trade StudyMaterial Basic
InformationPros Cons
Molybdenum Alloys
Used in turbine blades
Meets temperature requirements
Unsure of space worthiness
PICA Used as heat shield for entry into Earth/Mars atmospheres
Light weight, used in previous space missions
Expensive materials
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Plume Protection Trade Study Cont.
Molybdenum PICA
Density Okay Good
Space worthiness Unknown Good
Temperature Appropriate
Good Good
Costs Okay Bad
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Basic Material Properties
PICA (ablative material) (Phenolic Impregnated Carbon Ablators)
• Used on heat shield of Stardust Sample Return Capsule
• Designed by Lockheed Martin• Density of 0.224- 0.321 g/cm3
• Withstand at least 2700 degrees C
65
Propulsion
Nick Meinhardt
66
Propulsion Trade Study for Translational Motion
Main Thrusters Isp (s) Fuel OxidizerPower
Required ThrustFlight
History Complexity
Controlled shutoff/ restart
Monoprop Rocket medium storable N/A N/Amiddle range extensive simple yes
Storable Biprop medium storable storable N/Amiddle range extensive moderate yes
Solid Rocket medium storable N/A N/A high extensive simple no
Cryogenic Biprop highnot
storablenot
storable N/Aextremely
high limited complex yes
Ion Enginevery high storable N/A high
extremely small limited complex yes
Hall Thrustersvery high storable N/A high small limited complex yes
Electrothermal (Arcjet) high storable N/A high small extensive complex yes
Electrothermal (Resistojet) high storable N/A
extremely high small extensive complex yes
1
2
3
67
Propulsion Options for Attitude Control
Attitude Control Adjustment Translation
Power Required
3 Direction Rotation
Rapid Change in Direction
Combined Rot/Trans
Professional's Opinion (Steve Lee)
Monoprop Clusters fine-rough yes no yes yes
yes, off modulation great idea!
Momentum Wheel very fine none yes yes no
yes, with main thrust
probably would use a reaction wheel instead
Reaction Wheel very fine none yes yes no
yes, with main thrust
overkill for this application, usually used for photos
1
68
Thruster Requirements
• Attachment Method Frequired = 21N
• Provide attitude control capability• Provide translational capability• Exit mass flow rate
spe Ig
Fm
0
69
Flow Component RequirementsDesign Drivers:• Minimal pressure drop for rated flow• Monitor fuel conditions• Isolate systems: multi-fault tolerance against thruster fire• Provide parallel & series valve redundancy for reliability
Additional affecting factors:• Low power consumption (affects sizing of power supply)• Low response time (affects minimum turn angle)
70
Fuel Tank Requirements
•
•
- assume incompressible flow
- assume conservation of mass systemtank PPF
attach man error loading
attach man trapped
error loadingtrapped
attachmentmaneuvers
fuelfuel
fuelfuel
fuelfuel
fuelfuelfuel
005.0
03.0
VV
VV
VV
VVV
2
0sppiping
required
HNsystemtank
422
1
gIA
FPP
2pipingHNtank ))()(2
1(42UP
pipingpipingHN )(42
AUm
0 , gIUUmF spee
Burn ΔV or F Burn Time (s)
Fuel(kg)
Fuel(in3)
ΔV1 0.736 m/s 5.07 0.185
ΔV2 -8.07 m/s 55.7 2.03
Fattach 22.5 N 30.0 1.20
Total 4.32 261
71
Pressure Regulated vs. Blowdown Tank Pressurization
Comparison Pressure Regulated Blowdown
Component Complexity Complex Simple
Controls Complexity Simple Complex
Pressure loss None Function of propellant consumed
Loss in thruster force None Function of tank pressure
Mass Additional mass from pressurant monitoring components
Additional mass from added tank thickness to withstand high pressures
Pressurization Required Low 299 psi High 721 psi to complete mission
#tanks needed One Potentially two if not enough fuel volume available in high pressure tank
Change in performance between ΔV and Attitude maneuvers
None Isentropic expansion of pressurant results in temperature drop within the tank temporary lull in pressure.
Fits mission profile Yes No72
Propulsion Isolation Assembly &Thruster Orientation
Parallel
Series
73
Fuel Lines• Same length and number of 90 degree bends
in lines going to each thruster.
• Ltotal = 3.78m
• Bends = 9
74
Propulsion System Losses
20 N HYDRAZINE THRUSTER Model CHT 20
Max Tank Operating Pressure: 385.3 psia
Filter Pressure Drop: 5 psid at rated flow
Latch Valve Pressure Drop: <1 psid at rated flow
Solenoid Valve Pressure Drop: 25 psid (max) at rated flow
Total System Pressure Drop: 31.6 psidThruster Operating Pressure for Required Force: 267 psiaRegulate Tank Pressure Near: 299 psia
In – line pressure drop: 0.625 psid at 283 K, fully developed laminar flow
75
Component PropertiesComponent Product Max Operating
Pressure∆P, Flow rate Power
ConsumptionMax Response Time
Fuel Tank 385.3 psiaN/A N/A N/A
Fuel Filter 585.3 psia 5 psid 0.039 kg/s N/A N/A
Torque-Driven Latch Valve
405.3 psia 1 psid0.00998 kg/s
11.1 watts 50 ms
Dual-Seat Solenoid Valve
385.3 psia 25 psid (max)0.00998 kg/s
27 watts 15 ms
Service Valve 650 psia 30 psid0.0680 kg/s N/A N/A
20 N Thruster 320 psia0.00998 kg/s
27.5 watts(heater: 10
Solenoid: 17.5)-76
Propulsion Mass BudgetComponent Type
Manufacturer/Model Number Qty Unit Mass (kg) Total Mass (kg) Heritage
Propellant Tank AKT-PSI/80222-1 1 1.293 1.293 I.U.E.
Filter VACCO/F1D10638-01 1 0.18 0.180 Not Listed
Pressure Transducer Gulton-Statham/PA4089-450 5 0.26 1.820 DS1
Service Valve (gas) VACCO/V1E10483-01 FDV 1 0.11 0.110 DS1
Service Valve (liq) MOOG/Ref Model 50-856 5 0.209 1.045 MOOG IR & D, PMA, NSTAR
Latch Valve MOOG/Ref Model 52-266 8 0.65 5.200
Koreasat, LM 700, Globalstar, Iridium®, ETS-8, Smart-1, MT-
SAT2, Cosmo Sky Med
Solenoid Valve MOOG/Ref Model 51-281 16 0.299 4.784
GPS, ACE, CSII, Centaur, Skyret 4, COBE, Topex,
SFV,DMSP, USERS, SERVIS
Engines (15N req) EADS Astrium CH20 16 0.395 6.320
EURECA, HAPS, XMM, Integral, METOP, Herschel,
Plank
Tubing 1/4" 0.028" wall tubing N/A 5.00 5.000 DS1
Pressurant GHe N/A N/A 0.010 DS1/MER
Total Dry N/A N/A N/A 25.24 N/A
Propellant loaded N2H4 N/A N/A 4.420 Requirements
Total Wet N/A N/A N/A 29.67 N/A77
Off-Modulation
System Impact:
• Operating up to 4 thrusters at a given time to produce translational motion
• Max required flow rate through the latch & solenoid valves
= exit flow rate = F/ve = 0.00998 kg/s
• Max required flow rate through the filter
= 4 * exit flow rate = 0.0399 kg/s
• Max power consumed at once = 262 Watts
Def: turn off thrusters during a ∆V maneuver to compensate for unwanted rotations that are caused by an offset in CM.
78
Future Work• Model pressure control assembly & find
components.• Complete off-modulation dynamic model to
find more accurate fuel consumption information.
• CFD analysis using Monte Carlo methods to determine plume impingement effects on thrust.
79
GN&C
Jessica LattimerSam Zarovy
80
Jessica Lattimer
ApproachGN&C Hardware
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GN&C Assumptions• There exists space qualified versions of all devices• No redundancy in system devices – single string• Probability of landing on large rocks is so small that hazard avoidance
control system is not needed• Do not need pin point landing• Asteroid is the only gravity force acting on the spacecraft• Only disturbance torque acting on spacecraft is gravity• Cruise stage has cameras and GN&C system to navigate and determine
landing spot• Cruise stage will put spacecraft in any initial orbit we desire• Current project will use radar, next team will do trade study between
LIDAR and radar• Flight computer has enough processing power for all calculation and
command execution• The impulse force during landing only lasts t = 0.1 sec
82
Approach
Hohmman TransferNon-Hohmman Transfer
Time Okay Good
Fuel Efficiency Good Okay
Burn Complexity Good Bad
83
Free Fall Distance
Farther Away Closer
Time Okay Good
Crash Probability Good Bad
Reposition Chance Good Bad
Used a MatLab script to quantitatively analyze free fall distance
84
Approach
85
Attitude Determination
Star tracker Sun Sensors Magnometers GyroscopesEarth-Horizon Scanners
Range of Use Good Okay Bad Good Bad
Reliability Good Okay Bad Okay Bad
Errors Good Good Good Good Good
Weight Good Good Good Good Good
Size Good Good Good Good Good
Power Good Good Good Okay Good
86
Star TrackerGalileo Avionica A-STR Autonomous Star
TrackerFOV: 16.4 X 16.4˚Power Consumption: 8.9 W at 20˚C
13.5 W at 60˚CSize: 195 (L) X 175 (W) X 288 (H) mmMass: 3 kg
87
IMU
• Honeywell Miniature IMU• Mass: 5 kg• Size: 25 (D) X 20 (H) cm• Power Consumption: 30 W
88
Radar
• 3 Antennas– Mass : 1 kg each– Size : 20 cm diameter x 1 cm high each
• Central control box– Mass: 10 kg – Size: 30 cm x 20 cm x 15 cm
• Based off of MSL radar design
89
Radar Field of View
• Antennas only objects on bottom of spacecraft
• Landing gear is at 45˚ angle form vertical in descent
45˚
90
Sam Zarovy
Control System
91
Thruster Logic Vehicle Model
SensorUpdateGuidance
Algorithm+
-
Error
Vehicle State
Control Inputs
Estimated Vehicle State
Control Block
Control Update
Control System Architecture
Desired Vehicle State
92
Trajectory Input
93
Control Block
Attitude Error
Kp_att
+Attitude Update
Ki_att
Kd_att
1/S
S
++
Angular Rate Error
Kp_AR
+
Angular Rate Update
Ki_AR
Kd_AR
1/S
S
++
Velocity ErrorKp_vel
+Velocity Update
Ki_vel
Kd_vel
1/S
S
++
Altitude Error
Kp_alt
+
Altitude Update
Ki_alt
Kd_alt
1/S
S
++
94
Vehicle Model
• Use thruster firing as input to force and moments equations
• Estimate how thrusters will change vehicle state
95
Thruster Logic
• Torque produced by one thruster couple firing = 48 N*m• Minimum angle achievable: X-Axis = 0.0021 deg
Y-Axis = 0.0018 deg Z-Axis = 0.0023 deg
96
Control System Architecture: Sensor Update Block
Star tracker
Attitude Measurement
IMU - Gyros
Angular Rate Measurement
Filter: blend slow update rate of star tracker with fast update rate of gyros. Use highly accurate star tracker to remove gyro bias.
Estimated State
Filter: Use measurement to update estimated attitude and angular rate.
Estimated Attitude
IMU - Accels Acceleration Measurement
Estimated Velocity
Filter: Use measurement to update estimated velocity.
Radar
Altitude Measurement
Estimated Altitude Filter: Use measurement to update estimated
altitude.
Attitude State
Velocity State
Altitude State
Vehicle State
Filter: blend Radar ground speed measurements with acceleration measurements to calculate velocity measurement.
Ground Speed Measurement
Angular Rate StateEstimated Angular Rate
97
Flight Computer
98
Future Work
• LIDAR trade study• Further refine control blocks
99
Telecommunications
Ashley Chipman
100
Telecommunications
Requirement: Report back to orbiter
• Antenna: Conical Log Spiral (from Spacecraft Mission Analysis
and Design) 7.2 GHz receive band (X-band) Transmit 8.5 GHz
• Solid State Amp vs TWTA (traveling wave tube amp): Requires more power input SSA has a lower mass (wt limitations) more reliable (require lower voltages)
101
Low Gain Antenna
RF Switch Assembly
Telemetry Cond Unit
Comm. Det. Unit (Same as main command unit)
Transponder -- solid state amp
Telecommunications
102
Telecommunications
103
Component Mass (kg) Power (W)
Dimensions (m)
Placement
Med Gain Antenna(Conical Log Spiral)
1.36 10 Cone Diam 0.14Tube Diam 0.03Cone Depth 0.16
Ideally on top15 degree FOV
Transponder-- receiver-- transmitter
6.8712.540.0
0.14 x 0.33 x 0.07
Where fit** includes solid state amp
Comm. Detector Unit
N/A N/A N/A Same as main command unit
RF switches/cables(est. 10% of total)
0.908 N/AN/A
TBDTBD
Where needed
Telemetry Conditioner Unit
0.85 3.8 0.067 x 0.238 x 0.158
Where fit
Total Mass: 9.988 kg Total Power: 66.3WTotal Mass: 9.988 kg Total Power: 66.3W
Field of View
Star Tracker AntennaStar Tracker Antenna
1.82 meters
104
Thank you!
• Steve Lee – JPL• Professor Garrard• Professor Flaten• Professor Ketema
105
Questions?
106