PARACHUTES
Drogue
• 42in
• 83.59 ft/sec
Main
• 144in
• 22.45 ft/sec
DUAL DEPLOYMENT AVIONICS TEST
Main Charge
Drogue Charge
RAIL EXIT VELOCITY
65.2 ft/sec
Reach safe speed
at 66.34 inches
HULA-HOOP2 PLANNED FEATURES
2 memory options
 Model A: 256 Kbytes – built on multiple circuit boards
to be flown on the Leo Hano rocket
 Model B: 128 Kbytes – built on one circuit board to be
flown on an Executioner rocket
One version of the program code for all units
Variable sample rates – between 1 to 6 samples per
second
HULA-HOOP2 SUBSYSTEMS
Controller
 Main serial interface
 Debug port serial interface
 Field Input and Output
Data storage
Sensors & Analog to Digital Convertors (ADC)
 Temperature
 Acceleration
 Magnetic field
 12 bit ADC
Power
BLOCK DIAGRAM – V3
Accelerometer
(MMA7455)
BS2p controller
Coil X
ADC #1
(MCP3208)
I2C bus
Coil Y
Coil Z
EEPROM
(24LC512)
Hula-hoop2
03/18/11
version 3.1
ADC #2
(MCP3202)
SPI data bus
Temperature
Sensor (LM34)
CONTROLLER
D AT A S T O R A G E
Parallax Basic Stamp 2p
features:
Micro Technology 24LC512I/P EEPROM features:
 24 pin DIP
 8 code and/or data segments
at 2 Kbytes per segment
 16 digital Input/Output
interfaces
 Debug and program upload
interface
 Voltage regulator at +5 Volts
 8 pin DIP
 capacity of 65,536 bytes or 64
Kbytes per chip
 I2C interface
Memory sizes
 Model A: 4 chips for 256
Kbytes
 Model B: 2 chips for 128
Kbytes
SENSORS
T E M P E R AT U R E :
A C C E L E R AT I O N :
National
Semiconductor
LM34 features:
3 pin TO-92 case
Analog Output
Connected to
ADC#2
Parallax’s Freescale
MMA7455
Accelerometer features:
wider than usual 8 pin DIP
SPI or I2C interface – using SPI
3 axis acceleration
choices of 2g, 4g or 8 g – using
8g
 8 bit or 10 bit resolution – using
8 bit
 Digital Output




Data stream
 8 bits in
 8 bits out
SENSORS: MAGNETIC FIELD
Custom built inductors
Analog Output
3 coils will be used, one for each axis (X, Y and Z)
Each coil will have its own 4 resistor network that will be
connected to ADC#1
ANALOG TO DIGITAL
CONVERTORS: 12 BIT
ADC #1
ANALOG TO DIGITAL
CONVERTORS: 12 BIT
ADC #2
Micro Technology MCP3208
features
Micro Technology
MCP3202 features





16 pin DIP
12 bit resolution
8 single ended input channels
SPI interface
Adjustable voltage reference (.25
to 5 volts) while keeping the
device’s power supply at 5 volts.
Will be set at 1 volt
Data stream
 6 bits in
 12 bits out
 8 pin DIP
 12 bit resolution
 2 single ended input
channels
 SPI interface
Data stream
 4 bits in
 12 bits out