WVU Rocketeers Critical Design Review

1
WVU RocketeersCritical Design Review

• WVU
• Justin Yorick, Ben Province
• Advisors Dr. Vassiliadis, Marc Gramlich

2
CDR Presentation Content

• Section 1 Mission Overview
• Mission Overview
• Organizational Chart
• Theory and Concepts
• Concept of Operations
• Expected Results
• Section 2 Design Description
• Requirement/Design Changes Since CDR
• De-Scopes/Off-Ramps
• Mechanical Design Elements
• Electrical Design Elements
• Software Design Elements

3
CDR Presentation Contents

• Section 3 Prototyping/Analysis
• Analysis Results
• Interpretation to requirements
• Prototyping Results
• Interpretation to requirements
• Detailed Mass Budget
• Detailed Power Budget
• Detailed Interfacing to Wallops
• Section 4 Manufacturing Plan
• Mechanical Elements
• Electrical Elements
• Software Elements

jessicaswanson.com
4
CDR Presentation Contents

• Section 5 Testing Plan
• System Level Testing
• Requirements to be verified
• Mechanical Elements
• Requirements to be verified
• Electrical Elements
• Requirements to be verified
• Software Elements
• Requirements to be verified
• Section 6 Risks
• Risks from PDR to CDR
• Walk-down
• Critical Risks Remaining

5
CDR Presentation Contents

• Section 7 User Guide Compliance
• Compliance Table
• Sharing Logistics
• Section 8 Project Management Plan
• Schedule
• Budget
• Mass
• Monetary
• Work Breakdown Structure

6
Mission Overview

• Justin Yorick

7
Mission Overview

• The goal of this mission is to measure and record
  information about the atmosphere.
• These experiments will compare atmospheric
  readings to current models of atmospheric
  behavior.

8
Mission Overview

• Experiment overviews
• Flight Dynamics
• This experiment will measure the kinematics of
  the rocket flight, and will be used as a
  reference for the other experiments.
• Cosmic Ray Experiment
• The atmosphere is constantly barraged by foreign
  charge particles and waves from a variety of
  sources. The atmosphere shields the surface of
  the earth from these particles. As one travels
  further from the surface of the earth, the
  shielding effect decreases. By using an array of
  Geiger tubes, the team hopes to measure the
  concentration of cosmic rays in the atmosphere.

9
Mission Overview

• Radio Plasma Experiment
• In the earths atmosphere, energetic sources
  cause the ionization of gas particles. This
  region is collectively known as the ionosphere.
  The particles are known to oscillate at a given
  frequency, as a function of charge density. By
  using a variable frequency radio sweep, one can
  in theory find the resonance frequency of the
  ambient plasma. With this information, one can
  find the plasma density as a function of altitude.

10
Mission Overview

• Greenhouse Gas Experiment
• Various gases are thought to play a major role in
  the warming trends of earths environment.
  Certain gases such as water vapor and carbon
  dioxide are thought to play the most major roles
  in this process. Most atmospheric data for gas
  concentration is measured from a fixed point on
  the ground. It is the goal of this experiment to
  measure the concentration of the gases as a
  function of altitude, and provide some insight
  into their concentration profiles.

11
Mission Overview

• Dusty Plasma Experiment
• Although a plasma is regularly composed of
  charged gas particles in a dynamic equilibrium.
  In a dusty plasma, neutral particles of much
  larger particle diameter are suspended in a
  lattice equilibrium position. In a normal dusty
  plasma suspension, gravity plays a key role in
  lattice formulation. It is the goal of this
  experiment to study these lattices in the
  microgravity portions of this flight.

12
Organizational Chart
CFO Dimitris Vassiliadis
Structural Design Ben Province
Simulation and Testing J. Yorick
13
RockSat 2011 Concept of Operations
h117 km (T0253) Apogee
h75 km (T0118) RPE Tx ON DPE ON
h75 km (T0427) RPE Tx OFF DPE OFF
h52 km (T0036) End of Orion burn DPE begins
h10.5 km (T0530) Chute deploysRedundant atmo.
valve closed
h0 km (T1300) Splashdown
h0 km (T0000) Launch G-switch activationAll
systems power up except RPE Tx and DPE
14
RockSat 2012 GHGE Detailed Con-Ops
HTBD km tTBDCV decompresses to T -5C
2 H27.1 km t035s (T40C)
3 H17.2 km t322s (T-5C)
4 H10.0 km t352s (T-5C) 17 H1.8 km t742s
(T-5C)
1 H1.7 km t005s (T40C)
H1.52 km t771 s Wallops Valves Close
H1.52 km t004.x s Wallops Valves Open
15
Expected Results

• FD
• The expected results of the FD are the same as
  previous years, as the flight conditions are
  expected to vary little.
• CRE
• The CRE is expected to vary little from the 2010
  rocksat flight. In general, the counts are
  expected to increase as the vehicle gains
  altitude.

16
Expected Results CRE
17
Expected Results

• GHGE
• Current models predict that Carbon Dioxide is
  uniformly distributed in the lower atmospheric
  regions. The team assumes that this hypothesis is
  true due to the relatively homogenous nature of
  the lower atmosphere.

18
RockSat 2012 GHGE Temperature Ranges
Temperature (C)
Time (s)
19
RockSat 2012 GHGE Detailed Con-Ops
Sample Time (s) Altitude(km) T_target (C ) P_target (kPa) F_max (N) F_max (lbf)
1 5 1748 40 126.69 513.80 115.50
2 35 27060 40 13.34 98.46 22.13
3 322 17294 -5 27.30 177.46 39.89
4 352 10065 -5 58.55 190.47 42.82
5 382 6591 -5 63.07 114.63 25.77
6 412 5497 -5 64.98 83.87 18.85
7 442 5119 -5 65.70 72.25 16.24
8 472 4739 -5 66.45 60.01 13.49
9 502 4406 -5 67.13 48.79 10.97
10 532 4061 -5 67.86 36.66 8.24
11 562 3728 -5 68.59 24.44 5.49
12 592 3392 -5 69.35 11.57 2.60
13 622 3090 -5 70.06 142.07 31.94
14 652 2784 -5 70.79 147.34 33.12
15 682 2420 -5 71.70 153.87 34.59
16 712 2132 -5 72.43 159.23 35.80
17 742 1838 -5 73.21 164.90 37.07
Pressure (Pa)
Time (s)
20
Expected Results

• DPE
• In a regular dusty plasma, gravitational forces
  play a key role in the equilibrium position of
  the plasma lattice. The team expects to see an
  equilibrium lattice that is different in size and
  shape from standard models.

21
Design Description

• Ben Province

22
De-Scopes

• GHGE
• Originally, the team had hoped to measure the
  concentration of more GHGs in real time. This
  setup could not be realized under the current
  power, size and weight restrictions on the
  payload. Instead, the team has settled on
  measuring water vapor and Carbon Dioxide
  concentration, as a series of discrete steps
  throughout the payloads flight.

23
Descopes

• RPE
• Originally, the team hoped to use a relatively
  large Langmuir probe to verify the data found by
  the swept antennae. The size of the Langmuir
  probe has been reduced in size to be in
  compliance with WFF regulations.

24
Descopes

• DPE
• The original goal for the DPE was to control and
  stimulate a dusty plasma under microgravity
  conditions. At this point, the team is focusing
  on solely creating a dusty plasma in a
  microgravity setting.

25
Off-Ramps

• GHGE
• The team is currently finalizing a temperature
  control system for the GHG control volume. As it
  stands, current calculations show the air
  temperatures to be below chosen sensor ranges for
  portions of the flight. To control this problem,
  the team is attempting to use a master piston and
  cylinder to compress the air until it reaches the
  desired temperature. If this control scheme
  cannot be fully realized, the team will not take
  samples during portions of the flight with
  unacceptable temperatures.

26
Off-Ramps

• DPE
• As it currently stands, the team hopes to create,
  stabilize, and study a dusty plasma in
  microgravity conditions. If it becomes impossible
  to achieve all of these goals for one reason or
  another, the team may simply focus on creating
  the dusty plasma, and forgo the controlled
  stimulations of the sample.

27
Payload Mechanical Overview (1)
28
Payload Mechanical Overview (2)
29
Payload Mechanical Profile
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GHGE Mechanical Overview (1)
17-Tooth Cog ANSI 35 Roller-Chain
3/8 Ball Shaft
3/8 Ball Nut
26-Link ANSI 35 Roller-Chain (not shown)
Color CodePlates Which Must Be
Machined Threaded Rod Unthreaded Rod
Thrust Bearings
9-Tooth Cog ANSI 35 Roller-Chain
2 Bore X 1.5 Stroke Pneumatic Cylinder
Control Volume
Solenoids
1/8 NPT Piping (not finalized)
31
GHGE Mechanical Overview (2)
Color CodePlates Which Must Be
Machined Threaded Rod Unthreaded Rod
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GHGE Mechanical Overview (3)
12VDCElectric Motor
Color CodePlates Which Must Be
Machined Threaded Rod Unthreaded Rod
10-Tooth PulleyMXL Timing Chain
¼ to 3/8 Coupler
75-Tooth LoopMXL Timing Chain
Optical Encoder Wheel (not finalized)
60-Tooth PulleyMXL Timing Chain
¼ Threaded Rod supports plates
Adapter Platemates to canister floor
33
GHGE Mechanical Overview (4)
Color CodePlates Which Must Be
Machined Threaded Rod Unthreaded Rod
34
GHGE Mechanical Overview (5)
Color CodePlates Which Must Be
Machined Threaded Rod Unthreaded Rod
GHGE Control Board
Makrolon Plate (not finalized)
RPE RxBoard
35
Optical Plate Mechanical Overview
Power Board
FD Board
Optical Camera
Geiger Tubes
36
Optical Plate Mechanical Top View
37
Optical Plate Mechanical Bottom View
CREGeigerBoard
38
DPE Mechanical Overview
PlasmaControlVolume
Laser
DPEControlBoard
OpticalCamera
39
DPE Mechanical Top View
40
Electrical Design Elements

• PSS pcb

41
Electrical Design Elements

• FD pcb

42
Electrical Design Elements

• CRE pcb

43
Electrical Design Elements FD Board
Flash Memory
PSS
Camera µg
uMag X/Y/Z
uController Flight Dynamics
DI G I T A L
A D C
Geiger Counters
Thermistor
Temperature
Inertial Sensor
Z Accel
Ax/Ay/Az
Gyro X/Y
Camera Optical Port
P/Q/R
Battery
Mag X/Y/Z
44
Electrical Design Elements PSS board
Batt V
9V
Power Supply
3.3V
G
RBF
5V
555 Timer
-5V
GND
45
Electrical Design Elements FD Board
Flash Memory
PSS
Camera µg
uMag X/Y/Z
uController Flight Dynamics
DI G I T A L
A D C
Geiger Counters
Thermistor
Temperature
Inertial Sensor
Z Accel
Ax/Ay/Az
Gyro X/Y
Camera Optical Port
P/Q/R
Battery
Mag X/Y/Z
46
Software Design Elements
47
Prototyping/Analysis

• Justin Yorick

48
Analysis Results

• CRE
• The CRE has been prototyped thus far by building
  a Geiger circuit and developing code to interface
  this circuit with the Netburner microprocessor .
• Initial prototyping results suggest that the
  circuit will interface without major problems or
  failures.
• FD
• To ensure the FD subsystem functions as required
  a drop tower is being developed to test the
  accelerometers in axial directions, while spin
  testing with WVU CEMR will provide a suitable
  testing platform to monitor spin.

49
Analysis Results

• GHGE
• The designs for the GHGE are reaching a finalized
  state. With final dimensions, ANSYS finite
  element modeling will be utilized to calculate
  system stresses as well as heat transfer
  information in the piston, testing volume, and
  piping.
• Temperatures in the system are derived from an
  isentropic expansion of air. As the rocket is
  traveling above Mach 1, these assumptions yield
  the team with guideline values only.
• If needed, simple CFD may be performed using
  ANSYS or a suitable program.

50
Analysis Results

• RPE
• The RPE requires the successful timing of two
  swept frequency radio transmitters and receivers.
  The circuits are to be built, and tested using
  proper computational programs(name?) and
  oscilloscopes.

51
Analysis Results

• DPE
• The dusty plasma requires a RF transmitter with
  sufficient power to excite and ionize gas
  particles in a control volume. Once the circuit
  is finalized, the emitter must be tested both
  with an oscilloscope to ensure proper circuit
  output.
• The system must be used to actually excite a gas
  as well to ensure proper emitter design. (not
  sure how we test this..)

52
Detailed Mass Budget
53
Detailed Power Budget
Power Budget Power Budget Power Budget Power Budget Power Budget
Subsystem Component Voltage (V) Current (A) Time On (min) Amp-Hours
Netburner 3.3 .120 20 .04
Netburner 3.3 .120 20 .04
uMag XYZ 5 .020 20 .0066
IMU 5 .070 20 .0233
GYRO XZ 3.3 .0065 20 .00216
Z Accelerometer 5 .001 20 .00033
Thermistor 3.3 .00033 20 .00011
Flash 3.3 .006 20 .002
Flash 3.3 .006 20 .002
Op Amp -5 .068 20 .02266
Op Amp 5 .068 20 .02266
DPE 3.7 .438 10 .073
GHGE  12 1 2 .4
CRE 3.3  .120  20  .04
         
Total (Ahr) .67482
Over/Under .32518
54
Manufacturing Plan

• Ben Province

55
Mechanical Elements

• FD
• The FD subsystem needs little modification or
  manufacturing. The only foreseeable modifications
  could come in ballast placement to ensure proper
  GC and mass alignment of the canister.

56
Mechanical Elements

• CRE
• The CRE pcb must be finalized and readied for
  flight. The board will be ordered from
  PCBexpress.
• The Geiger array with varying shielding must be
  either rebuilt or reused from a previous flight.
  This is not anticipated to be an area of concern
  for the team.

57
Mechanical Elements

• GHGE
• The control volume must be assembled, most likely
  a custom glass vessel built by the chemistry
  department or the team.
• The appropriate tubing must be bought for the
  inputs, as well as control solenoids for the
  valve operations.
• A piston is to be ordered, and must be soundly
  interfaced to the system such that it forms an
  air tight seal with the CV, even at relatively
  high pressures.
• These components must all be assembled so that
  the experiment can control input temperatures
  during the flight.

58
Mechanical Elements

• RPE
• The antennae must be procured, and properly
  attached to the payload.

59
Mechanical Elements

• DPE
• The DPE will most likely required the use of a
  custom made, low pressure sealed experimental
  control volume. The team must also build a
  mechanism to disperse the dust within the vessel
  during flight. The team must also properly
  design, build, and attach the RF generator to the
  control volume.

60
Mechanical Elements
61
Electrical Elements

• FD
• The FD board requires little if any revision.
• CRE
• The team will utilize a custom built pcb for the
  Geiger array. This board must have the various
  components soldered to their correct locations.

62
Electrical Elements

• GHCE
• A pcb must be designed to enable to the sensors
  to interface with the Netburner, and also allow
  the Netburner to control the piston and valve
  system.
• Although this circuit should be relatively
  simple, some revisions may be needed because this
  will be the first round of the design process for
  the system component.

63
Electrical Elements

• RPE
• Multiple heritage elements will be used in this
  pcb. Slight revisions may be needed due to a
  change in antenna type from previous flights.
• The patch antenna itself must still be finalized
  and built. Although less likely, it is possible
  the antenna itself may need to be revised if not
  satisfactory.

64
Electrical Elements

• DPE
• The DPE makes use of an RF generator, a laser ,
  as well as a camera. The complexity of this task
  will result in an equally complex circuit.
• Due to the relatively complexity of this circuit,
  it seems probable that multiple revisions may be
  needed to have an acceptable and usable
  experiment.

65
Electrical Elements
66
Software Elements

• FD
• Some code modification will be needed to
  successfully activate and record data from new
  experiments.
• This code block affects all others because it
  controls the activation of further subsystems.

67
Software Elements

• CRE
• The CRE code will remain largely unchanged from
  previous years, and has little affect on other
  code blocks.

68
Software Elements

• RPE
• The general layout for this experiments coding
  will remain largely unchanged from previous
  flights. Changes will be focused on improving
  system performance and adapting the system to a
  new antenna.

69
Software Elements

• GHGE
• The code blocks for this must execute two primary
  functions. The first must record data from the
  gas sensors.
• The second major block must control valve
  settings and piston position, based on
  temperature predictions in addendum to current
  temperature readings.
• The team is considering the addition of a second
  Netburner to aid in control and data processing
  for this experiment.

70
Software Elements

• DPE
• The DPE code is yet to be fully developed, but is
  expected to accomplish the following
• The code must be able to activate and deactivate
  the experiment at the desired points in flight.
• The code must be able control the stimulation of
  the dusty plasma upon release of the dust into
  the CV.

71
Testing Plan

• Justin Yorick

72
System Level Testing

• FD
• As a whole, the FD must activate with g-switch
  triggering, as well as provide accurate recording
  of flight kinematics.
• CRE
• The CRE must activate and deactivate at its
  assigned times in flight (see Con-Ops).
• The CRE must also be able to detect high energy
  particles. To test this, the CRE will be placed
  next to known radioactive samples.

73
System Level Testing

• RPE
• The RPE must activate and deactivate at its
  assigned times.
• The transmitter and receiver will be tested on
  ground. The results arent expected to match
  ionosphere conditions, but this test will provide
  insight into the proper timing of the system.

74
System Level Testing

• DPE
• The DPE must activate and deactivate at proper
  times. The system must also be able to produce a
  plasma in the CV, and insert the dust particles
  at the proper time, as determined in the ConOps
  section.

75
System Level Testing

• Schedule

76
Mechanical Testing

• FD
• The FD subsystem will be assessed by placing it
  on a drop tower and then a spin platform. These
  test will not only verify the mechanical
  soundness of the system, but will aid in
  instrument calibration for the kinematic sensors.
• Test will also be used to find system mass and CG
  location.

77
Mechanical Testing

• CRE
• The CRE will be subjected to vibration and spin
  testing in addition to test that will measure the
  subsystem mass and CG.
• RPE
• The RPE will be vibration and spin tested. The
  subsystem will also be tested to find its mass
  and CG.

78
Mechanical Testing

• GHGE
• The redundant valves must be tested such that
  they are able to properly seal the canister in a
  water landing. This can tested by placing the
  valves in water.
• The solenoid control valves must be tested with
  pressurized air to ensure they are able to reach
  the required compression values.
• The piston should be strain tested to ensure
  failure is improbable.
• Spin and vibration testing will be used as well
  to ensure the system will survive.
• The mass and CG of this experiment are also very
  important due to the relative size of the piston.

79
Mechanical Testing

• DPE
• The DPE testing must verify that the low pressure
  CV will not break during the harsh conditions of
  the rocket launch. The subsystem will be spin and
  vibration tested to ensure its stability.
• The mass and CG of the system will also be found.

80
Electrical Testing

• FD
• The FD circuits remain largely unchanged. Testing
  with a DMM will ensure proper power distribution
  to other subsystems and the microprocessor.
• CRE
• The CRE must provide a digital out signal at less
  than 5v. The team must ensure this is met to
  avoid destroying the Netburner. The circuit must
  also provide the high potential voltage to the
  Geiger tubes. Both of these parameters can be
  verified with a DMM.

81
Electrical Testing

• RPE
• The RPE board must produce a relatively high
  frequency signal output with swept pulses. Upon
  completion, this circuit will be attached to an
  oscilloscope for output signal verification.
• The receiver can be attached to a similar scope
  to verify the receiver picks up the output pulses
  from the transmitter.
• This data must also be output in a form that can
  be recorded by the Netburner.

82
Electrical Testing

• DPE
• The DPE electrical components must produce an RF
  signal capable of producing a plasma in the low
  pressure CV environment. An oscilloscope would be
  a good tool to measure the outputs of this
  emitter.
• A DMM can be used to measure the signal outputs
  to the scanning laser.
• A more in depth software based approach may be
  needed to verify that the camera works to its
  specifications.

83
Electrical Testing

• GHGE
• The GHGE electronics must be able to provide
  sufficient power to the piston actuator, while
  also being able to power the solenoid valves.
  This can be tested by doing a test run in static
  air, as well as with a DMM.
• The signals from the GHGE sensors must also be
  within an acceptable voltage range to be
  successfully recorded by the Netburner.

84
Software Testing

• FD
• By triggering the g-switch, the team will be able
  to see if the current code will activate the
  payload as well record flight dynamics
  information.
• Although this code is paramount for other codes
  to activate, it is a successful heritage element
  from previous flights and major modifications are
  not expected.

85
Software Testing

• CRE
• The CRE code must be able to decipher digital
  pulses into a numerical count. This code sequence
  is also a heritage element, and little
  modification work is expected.

86
Software Testing

• RPE
• The RPE is expected to be able to send variable
  frequency wave pulses into a plasma environment.
  The coding must accurately control the RF circuit
  such that the pulse out and received are properly
  compared to one another.
• This task will require the completion of the
  previously mentioned electrical testing of this
  subsystem.

87
Software Testing

• DPE
• This code must be able to control the RF
  generation circuit and record the sensor data
  from the refracted laser.
• This software testing will rely heavily on the
  successful mechanical and electrical completion
  of the system.

88
Software Testing

• GHGE
• The GHGE code must be able to maintain the CV
  temperature in the prescribed range.
• To do this the team will simulate flow
  temperatures with compressed air. The algorithm
  must be able to position the piston such that the
  CV temperature lies within the acceptable range.
  

89
Risks

• Ben Province

90
Risk Walk-Down
Consequence Netburner fails in flight RPE sweep timing Failure DPE CV pressure loss
Consequence GHGE thermal controller fails
Consequence
Consequence Geiger tube array breaks on launch
Possibility Possibility Possibility Possibility

• Further research and Design have mitigated
  multiple risk in this mission.
• Further time must still be spent to lower the
  risk in the DPE apparatus.

91
Risk Walk-Down
Consequence Patch antenna Not properly calibrated
Consequence GHGE piston controller fails GHGE temp sensors fail
Consequence
Consequence
Possibility Possibility Possibility Possibility

• One risk of particular interest is the failure of
  the temperature controller mechanism in the GHGE
• Design refinement and thorough testing will
  result in a much lesser risk of this component
  failing.
• The risk of antenna failure will be lessened
  through the previously mentioned prototyping
  procedures.

92
User Guide Compliance

• Ben Province

93
User Guide Compliance

• Mass current predictions have payload at
  13.33lbf
• CG Although the CG is yet to be found through
  testing, it is believed to lie in the proper
  space, due in part to properly distributed
  battery cells and the relative magnitude of mass
  in the GHGE. It can be noted from the solid
  models that this experiment lies in the central
  axis of the payload.
• Batteries current power predictions have the
  total battery count as 15 9volt alkaline
  batteries.

94
Sharing Logistics

• The optical port from the Puerto Rico team
  canister will be used as the Special Port for the
  WVU payload.
• This is the only sort of sharing for this flight,
  because the WVU team purchased the entire
  canister space.

95
Project Management Plan

• Justin Yorick

96
Budget

• Approximate budgets
• PSS 200
• FD incl. magnetometers 1100
• RPE 600
• CRE 200
• GHGE 375
• Lead times of the order of lt1 week to 10 days.
• Funding sources West Virginia Space Grant
  Consortium, department of physics.
•  

97
Conclusion

• At this point, the GHGE and DPE need to be
  finalized in design.
• Once all component designs are finalized, the
  prototyping plan outlined in this presentation
  will be enacted.