New team
SLI 2012
The effect of gravitational stress on the diffusion of liquids.
February 17
Full scale vehicle completed
February 18
Full scale test flight #1
March 24/25
Full scale test flight #2 with payload
April 19/20
Flight hardware and safety checks
April 21
Launch day, full scale fight #3
April 28/29
Full scale flight #4 (tentative)
Coast
Event 3:
Apogee at
17s, 5252ft
Drogue
descent
Event 2:
Burnout at
2.24s,
1000ft
Apogee prediction
updated based on data
from scale model flight
(Cd=0.48):
5252ft
Event 1:
Ignition at
0s, 0ft
Event 4:
Main parachute
deployment at
84s, 700ft
Event 5:
Landing at
110s, 0ft
• Motor ignition
• Stable flight
• Altitude of 5,280 feet AGL reached but not
exceeded (most current prediction: 5252ft)
• Both drogue and main parachute deployed
• Vehicle returns to the ground safely with
minimal damage
• Safe recovery of the booster
CP
CG
Static margin
Length
Diameter
Liftoff Weight
Motor
83.1” from nosecone
65.6” from nosecone
3.2 calibers
108”
5.5”(body tube), 4”(booster)
21.5 lb
Aerotech K1050W
Letter
Part
A
Nosecone
B
Main Parachute
C
Drogue Parachute
D
Payload Bay
E
Transition
F
Motor Mount
G
Fins
•
•
•
•
•
•
•
•
Body: 5.5”/4.0” LOC Precision fiber tubing
Fins: 1/32” G-10 fiberglass + 1/8” balsa sandwich
Couplers: LOC Precision with stiffeners
Bulkheads, centering rings: 1/2” plywood
Motor mounts: 54mm Kraft phenolic tubing
Nosecone: Plastic nose cone
Rail buttons: standard nylon rail buttons
Motor retention system: Aeropack screw-on
motor retainer
• Anchors: 1/4" stainless steel U-Bolts
• Epoxy: Locktite epoxy
• We selected the AT-K1050W 54mm motor to propel
our rocket to but not exceeding an altitude of 5280ft
AGL
• The AT-K1050W motor provides an appropriate
thrust to weight ratio for our vehicle (9.8).
Length Mass Diamet
[in]
[kg] er [in]
108
8.9
Motor
Selection
5.5, 3.0 AT-K1050W
Stability Thrust to
Margin
weight
[calibers]
ratio
3.2
9.8
Burn
time
2.5s
Mach delay of 4 seconds will be set on both deployment altimeters
Apogee at:
5252ft, 17s
Max acceleration:
16 Gees
Maximum velocity:
520 mph
Mach number: 0.72
Wind Speed
[mph]
Altitude
[ft]
Percent Change in
Altitude
0
5252
0.00%
5
5240
0.10%
10
5204
0.40%
15
5168
1.60%
20
5101
2.80%
Parameter
Value
Flight Stability Static
Margin
3.2
Thrust to Weight Ratio
9.8
Velocity at Launch Guide
Departure (12ft AGL)
68mph
•
•
•
•
Wp - ejection charge weight [g]
dP - ejection pressure (15 [psi])
V - free volume [in3]
R - universal gas constant (22.16 [ftlb oR-1 lb-mol-1])
• T - combustion gas temperature
(3,307 [oR])
Parachute
Charge (g)
Drogue
2.4
Main
5.5
Charges will be finalized via static
ejection tests. Tests carried out with the
scale model indicated that average
increase of 30% against calculated values
may be needed for GOEX 4F powder.
Parachute
Descent
Weight
(lbs)
Parachute
Diameter
(in.)
Descent
Rate
(ft/s)
Kinetic Energy at
Impact
(ft-lb)
Drogue
18.75
18
68
N/A
Nosecone
Main
18.75
90
16
3.6
Body
27.6
Booster
29.0
Wind Speed
(mph)
Drift
(ft)
Drift
(mi)
0
5
10
15
20
0
814
1630
2444
3259
0
0.15
0.31
0.46
0.62
Tested Components
• C1: Body (including construction techniques)
• C2: Altimeter
• C3: Accelerometer
• C4: Parachutes
• C5: Fins
• C6: Payload
• C7: Ejection Charges
• C8: Launch System
• C9: Motor Mount
• C10: Beacons
• C11: Shock Cords and Anchors
• C12: Rocket Stability
Verification Tests
•V1 Integrity Test: force applied; verifies durability.
• V2 Parachute Drop Test: tests parachute functionality.
• V3 Tension Test: force applied to shock cords; tests durability.
• V4 Prototype Flight: tests feasibility of vehicle with scale model.
• V5 Functionality Test: tests basic functionality of device on ground.
• V6 Altimeter Ground Test: simulate altitude changes; verifies preset altitude
events fire.
• V7 Electronic Deployment Test: tests that electronics ignite deployment
charges.
• V8 Ejection Test: tests that deployment charges can deploy
parachutes/separate components.
• V9 Computer Simulation: RockSim predicts behavior of launch vehicle.
• V10 Integration Test: payload fits smoothly and snuggly into vehicle, and
withstands flight stresses.
V1
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
V2
V3
V4
V5
V6
V7
V8
V9
V10
Liftoff weight
Motor
Length
Diameter
Stability Margin
3.6 lb
Aerotech H250G
4 ft. 7 in.
2.6” body, 1.5”
motor tube
3.5
• Test drogue and main parachute deployment
• Test flight electronics (altimeters and ejection
charges)
• Test separation of body tubes at ejection
• Test validity of simulation results
• Test rocket stability
• Apogee- 2181ft
• Rocksim prediction 1900ft
• Time to apogee- 13s
• Apogee events
• Drogue deployment
• Main event
• Main parachute deploys at 700ft
Main parachute deployed at apogee and drogue at
700 ft (wiring error)
Calculated Cd :
0.48
Apogee for full scale
vehicle (Cd=0.48):
5252 ft
• On main parachute (from apogee): 21 ft/s
• After drogue deployment (700 ft): 21 ft/s
Due to the error in wiring, the main parachute was deployed by the apogee
event and drogue parachute by the set-altitude (700ft) event. We have added a
test to our preflight routine to prevent this problem from reoccurring.
Issue
Rocket trajectory wasn’t
completely straight
Mitigation
Fillet fins from inside rocket
(loose fin was the cause)
Two fins came loose during flight Fillet fins from inside rocket
(insufficient filleting)
Cross-wired the parachutes in
electronics bay
Double check parachute wiring
before flight, verify using audible
altimeter reporting
Rail button came off while
preparing rocket on the pad and
removing e-bay for altimeter
switch access
Have altimeter switches
accessible from outside the
rocket (through all outside walls)
We will investigate the effects of
acceleration and vibrations during
flight on the diffusion of dye into
liquids using digital imaging.
• Determine the effect of acceleration
on the diffusion of dye into liquids
• Determine the effect of vibrations
on the diffusion of dye into liquids
• Collected data from the camera and
accelerometers is accurate
• Vessels containing liquid do not leak
• Dye is injected into the liquid correctly
• Images from camera are received
• Acceleration is recorded
• Payload is recovered
Battery
LED
Syringe
Sealed
petri dish
Syringe
Sealed
Plexiglas
vessel
Camera
Camera
LED
Battery
Selection Rationale
• Fits inside the payload chamber
• Waterproof (in case of payload damage)
• Minimum focus is 1cm (0.4”)
• Full HD video 1920 x 1080 @ 30fps
• Sufficient memory/battery capacity
• Within the budget of our project ($300)
• Robust design (designed for extreme sports)
Rocket
Body
Bulkhead
Coupler
Tube
Launch and Boost
•
•
Dye is injected
into the solution
Camcorder
records the
diffusion process
The experiment chamber is
brightly lit using LEDs to
prevent
any
exposure
problems during recording
Coast and Apogee
The camcorder
continues to record the
diffusion process until
the vehicle reaches
apogee.
Accelerometer records
acceleration data.
Data Analysis
The pictures taken
during the flight
are analyzed
• Preflight ground tests
 Pictures of Petri dish from
overhead camcorder
 Water tank pictures from side
view
Experimental
Group
Control
Group
(stationary)
• Independent variables
a
Acceleration
t
Time after dye is released (flight time)
• Dependent Variables
R
Rate of diffusion (diffusion front speed)
P
Pattern of diffusion (qualitative
classification)
• R = f(a) Rate of diffusion in relation to
acceleration
• R = f(t) Rate of diffusion in relation to time after
dye is released
• P = f(a) Pattern of diffusion in relation to
acceleration
• P = f(t) Pattern of diffusion in relation to time
after dye is released
Test
Measurement
Rate of Diffusion
Dyed area boundary rectangle
expansion
Pattern of Diffusion
• Width to height ratio of dye
• Color saturation per pixel
• Voids in dye
Voids
Measure color
saturation in
each pixel
Boundary rectangle:
X pixels by Y pixels
To quantify the results of our experiment, we
have selected the following characteristics to
measure. Computerized digital image analysis
will be used and we expect to process over 7
billion pixels using a multicore Linux machine.
Characteristic
Measurement
Average void size
Measured in pixels
Void scattering
Number of void areas
Color dye spread
Clear vs. colored area (in pixels)
Directional dye spread
Width vs. height of color area
• We will use commercially available
accelerometers and altimeters
• The sensors will be calibrated
• We will do extensive testing on the
ground prior to the rocket launch
Tested Components
• C1: Camera
• C2: Injection
• C3: Diffusion Vessel
Verification Tests
• V1 Basic Function Test: testing the main functions of
the payload
• V2 Leak Test: verifying that the vessels containing the
liquid do not leak
• V3 Battery Life Test: verifying that the battery life of
the camera is long enough to take pictures during the
entire diffusion process
V1
C1
C2
C3
V2
V3