Team Flying Camels
Nawar Chaker
Pete Dokter
Tim Jacobs
Adam Swartley
Paul Savage
Capstone Project
February 24, 2005
Capstone Project
Team Flying Camels
Driftsonde System Overview
The National Center for Atmospheric Research,
NCAR, currently has a successful project involving a
high altitude pressure balloon that periodically drops
sensors (sondes) from a payload
NCAR would like to extend flight time, increase
maximum number of sondes to fifty while keeping the
balloon size the same
We are working on a new power system, health monitor
system and a release mechanism to meet specific
constraints given to us by NCAR to achieve their goals
Nawar
Capstone Project
Team Flying Camels
Driftsonde System
Iridium
OrbComm
LEO Satellite
LEO
Satellite
Zero-pressure
Balloon
Gondola Gondola
(24 sonde
(20-40
sondecapacity)
capacity)
~16km
50-100 mb
6 hours
between
drops
NORTH
AMERICA
© 2004 Copyright University
Corporation for Atmospheric Research
ATLANTIC OCEAN
EUROPE
Capstone Project
Team Flying Camels
Recap on Constraints
Power system
-A total weight of no more than 3Kg, including
solar panels, control system and batteries
-Batteries need to power the system for 24 hours
without recharge
-Solar panels need to replenish the batteries
enough to power system for ten days
Release Mechanism
-Must be wireless and must be addressable to fifty
sondes
Cost constraints have become secondary to
functionality
Nawar
Capstone Project
Team Flying Camels
Overall System Diagram
Solar
Panels
Laptop
Power System
Control
Solar
Panels
232 to CAN
Interface
Gondola RF
Control
RF Module
Two Way RF Link
RF Mod
RF Mod
RF Mod
RF Mod
RF Mod
RF Mod
RF Mod
Sonde RF
Control
Sonde RF
Control
Sonde RF
Control
Sonde RF
Control
Sonde RF
Control
Sonde RF
Control
Sonde RF
Control
Nawar
Capstone Project
Team Flying Camels
System Implementation
All hardware will be prototyped
Will not be doing board layouts
Will be simulating the gondola control system through
hyper terminal, which will interface to the CAN bus
Two PIC’S will be used:
-PIC18F258
-CAN bus capabilities
-Five A/D converters
-PWM
-PIC16F628A
-Inexpensive and simple
-Will runs on 3.3 V
Nawar
Capstone Project
Team Flying Camels
System Implementation
RF Modules:
-Fully contained units with antennas
-2.4GHz, 1M bit data rate
Solar Panels
-Four Iowa thinfilm panels
-Rated at 15 V and 100mA
Peak Power Tracker
-Maximizes power output
Batteries
-Six Lithium Ion rechargeable
-3.7 V, 2000mA-hrs
-2x3 configuration for the battery pack
Nawar
Capstone Project
Team Flying Camels
System Implementation
Programming tools
-MPLAB IDE 7.0
-MPLAB C18 Compiler
-Will program the chip
via EPIC programmer,
using X-2 development
board
Nawar
PIC18F258-I/SP
D
D
V
VSS
8
1
0
2
RC7/RX/DT
RC6/TX/CK
7
1
RC5/SDO
MCLR/VPP
RC4/SDI/SDA
1
RC3/SCK/SCL
1
RC2/CCP1
1
RC1/T1OSI
RC0/T1OSO/T1CKI
1
.1uF
1
8
OSC1/CLKI
R1IN
9
3
1
8
C
OSC2/CLKO/RA6
6
1
5
4
3
2
1
RB7/PGD
8
2
RB6/PGC
7
2
0
VSS
1
6
R2IN
1
8
1
C
R1OUT
2
9
=Value
R2OUT
2
1
9
5
6
1
1
RB5/PGM
RA5/AN4/SS/LVDIN
T2OUT
T2IN
6
2
7
7
0
1
7
F
u
1
4
B
R
RA4/T0CKI
T1OUT
T1IN
5
2
6
4
1
1
1
3
0
1
1
1
1
F
u
1
VEE
D
N
G
9
Connector
D
=Value
CANH
7
8
RB2/CANTX/INT2
RA2/AN2/VREF-
3
4
2
5
4.7K
C2-
4
RB3/CANRX
RA3/AN3/VREF+
8
3
2
4
5
4
F
u
1
6
2
RB1/INT1
RA1/AN1
C2+
3
C
CANL
2
2
3
4
9
1
R
=Value
5
1
RB0/INT0
RA0/AN0/CVREF
VCC
C1-
1
2
2
6
1
3
5
F
u
1
D
D
V
C1+
SN75LBC031
2
1
.1uF
.1uF
=Value
1
J
4
C
PIC18F258
MAX232
F
u
1
C10
9
C
=Value
2
C
5
C
+5V
+5V
+5V
+5V
F
p
8
1
7
C
1
2
XTAL1
F
p
8
1
6
C
Capstone Project
Team Flying Camels
Serial to CAN Bus Link
Pete
F
p
8
1
C16
PIC18F252-I/SP
1
2
XTAL2
.1uF
Cap
F
p
8
1
D
D
V
VSS
8
1
0
2
C13
RC7/RX/DT
RC6/TX/CK
1
MCLR/VPP
1
RC4/SDI/SDA
1
RC3/SCK/SCL
1
RC2/CCP1
1
.1uF
RC1/T1OSI/CCP2
1
RC0/T1OSO/T1CKI
1
C14
5
3
Y
3
A
8
9
OSC1/CLKI
2
Y
2
A
9
6
5
OSC2/CLKO/RA6
1
Y
1
A
3
2
7
RC5/SDO
6
1
5
4
3
2
1
0
1
9
4
RB7/PGD
8
2
8
3
RB6/PGC
7
2
0
8
+3.3V
1
1
2
1
1
VSS
4
R
4
Y
4
A
9
C12
4.7K
7
1
.1uF
C15
D
N
G
7
2
RB5/PGM
RA5/AN4/SS/LVDIN
6
2
7
4
6
1
4
B
R
RA4/T0CKI
OE4
3
7
8
CANH
5
2
6
3
1
RB3/CCP2
RA3/AN3/VREF+
OE3
2
6
TRF2.4G
4
2
5
0
1
CANL
RB2/INT2
RA2/AN2/VREF-
OE2
1
5
3
2
4
4
RB1/INT1
RA1/AN1
VCC
OE1
2
2
3
4
1
1
SN75LBC031#2
RA0/AN0
MM74C906
RB0/INT0
1
2
2
4.7K
2
R
C11
.1uF
PIC18F258#2
+5V
+5V
4.7K
+3.3V
+3.3V
+5V
3
R
+3.3V
Capstone Project
Team Flying Camels
Gondola RF Control
Pete
PN2222A
1
Q
0
3
3
.1uF
D
D
V
VSS
1
4
R
0
R
3
3
1
RB7/T1OSI/PGD
RA7/OSC1/CLKIN
6
1
4
1
C
1
5
2
C
.1uF
LED0
RB6/T1OSO/T1CKI/PGC
RA6/OSC2/CLKOUT
2
1
5
1
5X2A
Header
DS2
5
B
R
RA5/MCLR/VPP
1
1
4
LED0
RB4/PGM
RA4/T0CKI/CMP2
0
1
5
0
1
3
DS1
RB3/CCP1
RA3/AN3/CMP1
9
4
9
2
S
C
K
1
RB2/TX/CK
RA2/AN2/VREF
8
3
VCC
8
1
DR1
1
R
RB1/RX/DT
RA1/AN1
7
2
7
8
1
CLK1
0
3
3
RB0/INT
RA0/AN0
6
1
6
7
1
Data
5
R
VCC
+3.3V
TRF-2.4G
PIC16F628A
+3.3V
+3.3V
Capstone Project
Team Flying Camels
Sonde Schematic
Pete
Capstone Project
Team Flying Camels
RF Link Firmware Flowchart: Gondola
Start
Wait for TX Command
from CAN
INIT for TX,
Transmit address
and command
INIT for RX,
(delay) wait for RX
No
DR High?
Yes
Clock out Data
Check for ACK
No
Good ACK?
Yes
Pete
Capstone Project
Team Flying Camels
RF Link Firmware Flowchart: Sonde
WAKE UP
Power Down
for sleep period
INIT for RX,
Wait for RX
No
DR High?
Yes
Clock out Data
Check address
No
Good
Address?
Yes
INIT for TX,
send ACK
Execute command
Was last
Yes
Command to
drop?
No
Yes
Power Down
Pete
Capstone Project
Team Flying Camels
Solar Panels
MPT15-150 by Iowa thinfilm
Operates at 15.4 V and 100 mA
Total weight of 26.0g
Will wire four in parallel to
keep the voltage steady and
provide the needed current
Tim
Capstone Project
Team Flying Camels
Peak Power Tracker
I-V characteristic for the solar panels
Peak power tracker finds the maximum power point on
the curve
This is necessary for maximum efficiency
Tim
PIC18F258-I/SP
D
D
V
VSS
VCC
8
RC7/RX/DT
1
8
0
VSS
2
9
1
F
p
8
1
RC6/TX/CK
7
1
RC5/SDO
MCLR/VPP
9
C
6
1
1
RC4/SDI/SDA
5
1
RC3/SCK/SCL
4
1
RC2/CCP1
3
1
1
2
RC1/T1OSI
XTAL1
2
1
RC0/T1OSO/T1CKI
1
1
F
p
8
1
RB7/PGD
OSC1/CLKI
8
2
9
RB6/PGC
OSC2/CLKO/RA6
C10
7
2
0
1
RB5/PGM
RA5/AN4/SS/LVDIN
6
2
7
7
3
RB3/CANRX
RA3/AN3/VREF+
8
CANH
5
2
6
4
4
B
R
RA4/T0CKI
CANRX
4
2
5
6
2
RB2/CANTX/INT2
RA2/AN2/VREF-
CANL
CANTX
3
2
4
5
1
RB1/INT1
RA1/AN1
2
2
3
RB0/INT0
RA0/AN0/CVREF
SN75LBC031
1
2
2
.1uF
1
U
C11
K
1
Res1
+5V
R12
F
u
1
F
u
1
6
C
K
1
5
C
DISfromPIC
K
1
R11
Res1
R10
4
5
1
3
K
1
4
6
Res1
2
5
Amp
Op
7
VCC
8
AtoPIC
1
TSC427#2
R13
3
6
2
Amp
Op
7
DISOK
8
LM258
K
1
VCC
BtoPIC
Res1
4
4
K
1
5
5
9
R
Res1
1
1
3
3
8
R
DisCurrent
6
6
2
VCC
2
PULSEFROMPIC
Amp
Op
Amp
Op
7
7
8
ChargeCurrent
8
AR3
TSC427
SPVoltage
PULSETRAIN
VCC
.005
.005
.005
Res1
Res1
Reg
Volt
D
N
G
SP-
R16
2
R
7
R
F
p
0
0
1
F
p
0
0
1
K
1
.1uF
.1uF
Cap
Cap
Res1
F
p
0
0
1
K
1
Cap
7
C
8
C
3
C
4
R
MOSFET-P
Cap
Res1
4
C
D
N
G
1
Q
C12
6
R
Vout
Vin
F
u
0
2
2
78M05
F
u
0
2
2
1
C
2
C
K
1
2
Header
Res1
4.7K
2
Header
VCC
R14
Res1
2
4.7K
5
R
2
1
Trans
Batt+
Res1
1
JP1
3
R
JP3
PANEL
*SOLAR
MOSFET-P
2
Diode
Diode
2
2
Q
Res1
1
SP+
1
R
1
T
JP2
2
D
1
D
Capstone Project
Team Flying Camels
Power System Schematic
Tim
Capstone Project
Team Flying Camels
Batteries
Sanyo Rechargeable
3.6 V and 2 A-Hrs
Flat top lithium ion
$15.79 a piece
Pack will be 10.8 V and 4
A-Hrs consisting of six
cells
Tim
Capstone Project
Team Flying Camels
Batteries
Charge Characteristics
Tim
Capstone Project
Team Flying Camels
Batteries
Discharge Characteristic
Tim
Capstone Project
Team Flying Camels
Power System Firmware Flowchart
Initialize I/O ports, A/D, PWM, CAN
Yes
Previous Watts>
New Watts
No
Delta=-Delta
PWM Duty Cycle % Max += Delta
Sample A/D to obtain new values
Stop Charging
Duty Cycle=0
Yes
Yes
Discharge Voltage < Minimum
No
Charge Current<Minimum
Continue Charging
No
Place A/D values in CAN Data Registers
Sample A/D to obtain new values
Place A/D values in CAN Data Registers
New Watts = Solar I * Solar V
Delay 50 ms
Adam
Capstone Project
Team Flying Camels
Current State of Project
RF System:
- Two RF modules and PICs breadboarded
- Test code currently functions for two-way
communication
- Schematics complete
- Addressing and command structure next
- Prototype ten RF modules after that
Adam
Capstone Project
Team Flying Camels
Current State of Project
Power System:
- Schematics complete
- Solar panels functional
- Test code running for PIC
-Developing different aspects of firmware
- Prototype and test system components next
Adam
Capstone Project
Team Flying Camels
Parts List
Part Description
Quantity Unit Price Total Price
PIC18F258
8
$10.55
$84.40
IC TRANSCEIVER CAN
15
$1.48
$22.20
IC DUAL OP AMP
15
$0.55
$8.25
IC VOLT REG ADJ
15
$1.05
$15.75
IC MOSFET DVR
15
$1.08
$16.20
PC BOARD 2-SIDE
3
$15.38
$46.14
CONN IC SOCKET 18 PIN
10
$1.20
$12.00
IC HEX INV BUFF/DRV
10
$0.46
$4.60
CONN IC SOCKET 28 PIN
10
$0.69
$6.90
HIGH SPEED TRANSCEIVER
13
$20.90
$271.70
RECHARGEABLE LITHIUM-ION
6
$15.79
$94.74
S-MPT15-150 SOLAR PANEL
4
$42.75
$171.00
Total
$753.88
Paul
Capstone Project
Team Flying Camels
Gantt Chart
Paul
Capstone Project
Team Flying Camels
Division of Labor
Pete: RF system, hardware implementation, serial link,
coding
Paul: RF system, CAN bus, serial link, coding,
purchasing
Nawar: Power system, circuit design, hardware
implementation, documentation
Tim: Power system, hardware implementation, circuit
design, batteries
Adam: Power system, firmware, CAN bus, serial link
Overall system implementation will be done by the
entire team
Paul
Capstone Project
Team Flying Camels
Questions/ Comments?