Critical Design
Review
Team: Half n’ Half
Jasmine Jihyun Kim, Claire Lawson, Jason Myer,
Gabriel Seitz, Kevin Sternberg, Julie Yamashita
CDR Outline
• Project Overview
• ZigBee Subassembly
• RF Subassembly
• Prototype
• Budget
• Division of Labor
• Schedule
Half n' Half CDR
6/27/2016
1
Project Overview
• Our goal is to create a wireless system that tracks in
real-time the location and ranking of cyclists in a bike
race and displays this to the spectators and each rider.
Half n' Half CDR
Photo Credit: http://randy4u.blogspot.com/2007_07_01_archive.html
6/27/2016
2
System Block Diagram
Half n' Half CDR
6/27/2016
3
ZigBee BeeStack
 Beestack
 Software that’s placed into all target boards
 BeeStack architecture allows for:
 Networking Components (Mesh Network)
 Platform Components (Hardware)
Half n' Half CDR
6/27/2016
4
BeeStack Protocol: IEEE 802.15.4
 Compliant with IEEE 802.15.4 standard
 IEEE 802.15.4 standard defines :
 Physical Layer (PHY)
 Medium Access Control Layer (MAC)
Half n' Half CDR
6/27/2016
5
BeeStack: ZigBee Alliance Protocol
 ZigBee Alliance adds the NWK, APS, AF, ZDO, ZDP
layers
 Allows us to set the foundation for a mesh network
 Allows us to utilize the mesh network with our custom
application
 Network creation
 Network configuration
 Data packet routing
 Handles requests and responses
 Sends acknowledgements
Half n' Half CDR
6/27/2016
6
Mesh Network
 Mesh topology provides AODV (Ad hoc) routing
protocol
 Self-forming (when conditions change)
 Self-healing (when nodes are lost)
 Multihop routing capability, thus can locate multiple
mobile nodes
 Via Freescale MC13224v (discussed later)
Half n' Half CDR
6/27/2016
7
Mesh Network
 Bike contact time is long
 Mesh network is capable of handling these times
Time in Seconds Time in Seconds
(25mph, 40kph)
(75mph, 120kph)
Contact Distance
1m
100m
0.03
90
30
Time per biker for Time per biker for Time per biker for Time per biker for
1m at 40kph in
1m at 120kph in 100m at 40kph in 100m at 120kph in
Seconds
Seconds
Seconds
Seconds
Peloton Size (Number of Bikers)
Half n' Half CDR
0.09
3
0.03
0.01
30
10
10
0.009
0.003
9
3
25
0.0036
0.0012
3.6
1.2
50
0.0018
0.0006
1.8
0.6
100
0.0009
0.0003
0.9
6/27/2016
0.3
8
ZigBee Mobile Node
 Will either beacon or receive data from Static Node the biker’s
rank to display onto LCD
 Rank position from Mobile Node to a Shift Register will use SPI
 MC13224V has external SPI modules with 4 pins in SPI port
(SPI_SCK, SPI_MOSI, SPI_MISO, SPI_SS)
 Shift Register
 Serial to parallel-out since LCD is a parallel-out device
 74HC595
Half n' Half CDR
6/27/2016
9
Half n' Half CDR
6/27/2016
10
ZigBee Router
 Routes data between static nodes to coordinator
 Will either relay data to the Coordinator
 Will relay ranking back to the Mobile Node
Half n' Half CDR
6/27/2016
11
Half n' Half CDR
6/27/2016
12
ZigBee Coordinator

Facilitates communication between mesh network and main server

Will determine and store cyclists’ location

How it works:
 Starts the mesh network
 Selects PAN ID for network

Can add and remove other nodes from network

Input: Receives raw RSSI data from mesh network via IEEE 802.15.4 transceiver

Outputs: Position data via UART
Half n' Half CDR
6/27/2016
13
Half n' Half CDR
6/27/2016
14
System Block Diagram
Half n' Half CDR
6/27/2016
15
Comm: MSP430 to Laptop
Half n' Half CDR
6/27/2016
16
MSP430-F449
 Frequency – 8MHz
 Flash – 60KB
 SRAM – 2048B
 GPIO – 48
 LCD Segments - 160
Half n' Half CDR
6/27/2016
17
MSP Schematics
 Main board





P3.0 CSN
P3.1 MOSI
P3.2 MISO
P3.3 CLK
P1.6 CE
Half n' Half CDR
6/27/2016
18
MSP Schematics
 Inputs
Half n' Half CDR
6/27/2016
19
MSP Schematics
 Outputs
Half n' Half CDR
6/27/2016
20
NRF24L01
 NRF24L01





Low cost single-chip 2.4GHz RF transceiver IC
Worldwide license-free 2.4GHz ISM band operation
1Mbps and 2Mbps on-air data-rate
Ultra low power consumption
On-air compatible with all Nordic nRF24L Series in 1 and
2Mbps mode
 On-air compatible with Nordic nRF24E and nRF240
Series in 1Mbps mode
Half n' Half CDR
6/27/2016
21
RF Communication
MiRF-v2
IC
Half n' Half CDR
6/27/2016
22
NRF24LR Schematics
 MOD-NRF24LR





P1 CE
P2 CSN
P3 SCK
P4 MISO
P5 MOSI
Half n' Half CDR
6/27/2016
23
UART Communication
 Receives and Transmits data between MSP430 and
Coordinator/Laptop
 Receives position info from Coordinator
 Receives bike info from Laptop
Half n' Half CDR
6/27/2016
24
UART Software Flow Chart
Initialize UART
Yes
Ready
Bit?
No
Send Ready Bit
Receive Data
Transmit Data
Half n' Half CDR
6/27/2016
25
SPI Communication
 Receives and Transmits data between MSP430 and
RF chip
 Data can be received from several transmissions
Half n' Half CDR
6/27/2016
26
SPI Software Flow Chart
Initialize SPI
Yes
Send Ready Status
No
No
Ready
Status?
Receive and Store
Data
Transmit Data
Data
Read?
Received?
No
Yes
Yes
Clear Register
Half n' Half CDR
6/27/2016
Send Status and
Clear Register
27
Proof of Concept
Half n' Half CDR
6/27/2016
28
Hardware: Digi - XBee S2
• Series 2 are made for Mesh Networks
• Objective: Use 3 XBee devices to read RSSI
values
• 1 Coordinator and 2 Router nodes
Half n' Half CDR
6/27/2016
29
Prototype Results
•
RSSI Testing: Range -30dBm to -100dBm
•
RSSI (approx) = 1/R2
•
Results: As a Router increased distance from the coordinator,
the RSSI value dropped
Half n' Half CDR
http://www.sensorsmag.com/networking-communications/asset-tracking/asset-tracking-industrial-settings%E2%80%94a-review-wireless-technol-1500
6/27/2016
30
XBee Downfall
• RSSI is not accurate enough to provide
reliable position calculation
• XBee S2 are meant for Sensor Mesh
Networks, not tracking
Half n' Half CDR
6/27/2016
31
Hardware: Freescale MC13224v
• Can be used for ZigBee mesh networking
• IEEE 802.15.4 standard compliant on-chip
•
•
•
•
transceiver/modem
Low Power
Low Cost
High Reliability
No external RF components required
• μController: 32-bit ARM7TDMI-S CPU @ 26
MHz
• SPI/I2C/UART
Half n' Half CDR
6/27/2016
32
Useful Pin
Assignments
Pin #
Pin Name
Type
9
TDO
Digital I/O
JTAG Test Data Output / GPIO49
JTAG debug port serial data output.
10
TDI
Digital I/O
JTAG Test Data Input / GPIO48
JTAG debug port serial data input.
11
TCK
Digital I/O
JTAG Test Clock Input / GPIO47
JTAG debug port clock input.
12
TMS
Digital I/O
JTAG Test Mode Select Input / GPIO46
JTAG debug port test mode select
input.
13/17
UART2/1_RTS
Digital I/O
UART2/1 Request to Send input /
GPIO21/17
UART RTS control input
14/18
UART2/1_CTS
Digital I/O
UART2/1 Clear to Send output / GPIO20/16
UART CTS control output
15/19
UART2/1_RX
Digital I/O
UART2/1 RX data input / GPIO19/15
UART receive data input.
16/20
UART2/1_TX
Digital I/O
UART2/1 TX data output / GPIO18/14
UART transmit data output
56/57
ANT_1/2
Digital I/O
Control output for external RF
component / GPIO42/43
Programmable control pin.
45
VBATT
Power Input
High side supply voltage to buck regulator
switching MOSFET and IO buffers
Connect to battery.
Half n' Half CDR
Description
Functionality
6/27/2016
33
Hardware: Redwire Econotag
•
•
•
•
•
Freescale MC13234v
PCB Inverted-F Antenna
USB-A connector
Powered from USB or Battery
No Additional Hardware
Half n' Half CDR
6/27/2016
34
Budget
Item Name/Description
RedWire Econotag (Sample + Shipping)
Redwire Econotag (Remainder + Shipping)
Digi Xbee S2 (SparkFun)
MSP430 Chip
PCB Design ($33 per board + $50 Tileing)
Node Stand (PVC) 1" x 5'
LCD Display 20x4 5Volt (Bike)
Lightweight Battery LS14500 AA 3.6V
2.4GHz Duck Antenna RP-SMA WRL-00558
Workstation Processor/Display
Olimex MSP430 Display Board
Antenna for Olimex MSP430 Display Board
Bike Module Shift Register (74HC595) from SparkFun
RF Chip
Unit Price
Quantity
Total Amount
$64.75
4
$259.00
$51.70
10
$517.00
$28.75
3
$86.25
$10.00
2
$20.00
$83.00
1
$83.00
$5.00
40
$200.00
$15.00
3
$45.00
$6.00
20
$120.00
$11.00
2
$22.00
$200.00
1
$200.00
$42.46
2
$84.92
$11.95
2
$23.90
$1.50
1
$1.50
$4.00
2
$8.00
$1,670.57
Half n' Half CDR
6/27/2016
35
Division of Labor
Jasmine
Claire
Jason
Gabe
Kevin
Julie
Bike Module Rx-Tx
System
P
S
P
Bike Module
Algorithm
S
S
P
Checkpoint System
Rx-Tx System
P
P
S
S
Checkpoint Server
Algorithm
P
S
S
P
Main Server Rx-Tx
System
S
P
Main Server
Algorithm
P
PCB Board Layout
Half n' Half CDR
P
P
Display Systems
P
P
S
P
P
6/27/2016
36
Schedule
Half n' Half CDR
6/27/2016
37
Milestones
 Milestone #3:
 ZigBee: Mesh Network Setup and Triangulation
 RF: Coordinator MSP to Spectator Display
 Milestone #4:
 ZigBee: Track multiple mobile nodes
 RF: Placement calculations
 DEMO!
 Record bike race and have a video in room
 Set up system out side, show audience on time intervals
Half n' Half CDR
6/27/2016
38
Questions?
•
Half n' Half CDR
Photo Credit: http://fpafinancialplanningblog.files.wordpress.com/2011/11/question.jpg
6/27/2016
39
Sources
•
https://www.sparkfun.com/products/10415
•
http://www.digi.com/support/productdetail?pid=3352
•
https://www.sparkfun.com/products/8687
•
http://ftp1.digi.com/support/documentation/90000976_G.pdfhttp://www.freescale.com/files/rf_if/doc/data_sheet/
MC1322x.pdf
•
http://www.redwirellc.com/store/node/1
•
http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MC13224V
•
http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=BEEKIT_WIRELESS_CONNECTIVITY_T
OOLKIT
•
http://www.cs.unibo.it/bononi/SRW2011/SRW2011_6.pdf

http://cache.freescale.com/files/rf_if/doc/ref_manual/BSSRM.pdf

http://www.freescale.com/files/microcontrollers/doc/brochure/PositionLocationMonitoring.pdf

http://www.circuitsathome.com/mcu/interfacing-lcd-via-spi
Half n' Half CDR
6/27/2016
40