Transcript Critical Design Review

BROBOT
THE STUDY COMPANION
GROUP 25
Richard
Landau
Sarah Patten
Jacob Stewar t
PROJECT OVERVIEW
 BroBot assists in easing the minds of students longing for a
worry -free break.
 Watches study materials while the user is away from the
table.
 Sends updated images and alerts to user through an Android
app on user’s phone.
 Will provide real-time updates and will notify user if
something is stolen.
GOALS AND OBJECTIVES
 Detect theft of an object.
 Alert user when a theft
occurs.
 Be reliable and simple to
use.
 Rechargeable or easily
replaceable battery
 Be lightweight, portable, and
af fordable.
DESIGN SPECIFICATIONS
Specification
Weight
Less than 3 lbs
Dimensions
Less than 6inX6inX6in when closed
Communication Range
At least 250 ft
Battery Life while in
operation
At least 2 hours
Image Comparison Rate
2/sec
Refresh App Picture
Every 15 seconds
OVERALL BLOCK DIAGRAM
PROCESSOR CONSIDERATIONS
 All of the computations are on the microcontroller
side
 A good amount of serial communication protocols
(SPI, I2C, UART)
 Low power modes including sleep mode
 Special features with digital cameras (?)
 Good community backing
 Cheap development board with all the pin outs on
the microcontroller
ARM MICROCONTROLLERS
TM4C123GH6PM
STM32F407VG
ATSAM4S
Flash Memory
256 KB
1 MB
1 MB
SRAM
32 KB
192KB
128 KB
GPIOs
43
72
47
Max Speed
80 MHz
168 MHz
120 MHz
Package
64 LQFP
100 LQFP
64 LQFP
Dev Price (USD)
12.99
14.90
39.00
Board pluses
Not too many
Comes with many
output pins but has MEMS sensors and
good community
all output pins
behind it
Comes with 2GB
external flash and
all output pins
STM32F407VG
 3.3V Voltage
 Low power modes
 Digital Camera
Interface(DCMI)
 Can take 8 bit parallel data
from a camera
 Good amount of SRAM
 Fast operation speed
 A lot of serial
communication lines
 Good community backing it
with pre-written libraries for
most features
CAMERAS
MT9D111
LinkSprite JPEG Color
Camera
Control Communication
Own protocol
UART
Data Lines
8 Bit Parallel
UART
Voltage
3.1V
5V
Current (Max Operation)
350 mA
100mA
Max Resolution
1600x1200
640x480
Cost
20.00
44.95
MT9D111









Cheap and small
Adjustable output
Adjustable resolution
Adjustable quality on the
JPEGs
Parallel data
Control on shutter speed,
and auto focus
Sleep modes
Has own serial protocol
Interfacing parallel data
might be tricky
LINKSPRITE JPEG COLOR CAMERA
 Local shipping
 Higher voltage needed
 Data is serial making it
easier to interface but
slower overall
 Smaller resolution
 Will be used mostly for
testing, or used if we have
troubles with the MT9D111
 Bought since we are under
budget
BLUETOOTH VS WIFI-DIRECT
 Wi-Fi direct and Bluetooth
are comparable
 Wi-Fi direct has longer range
than Bluetooth
 However, Bluetooth has more
support and is easier to
implement
 Bluetooth is also more
common in everyday life so
we wanted experience with it
Bluetooth Module Comparison
Name
TI LMX9830
BC04
RN41
BLE112
WT41
Connection
Type
UART
UART
UART
UART
UART
Range
2 – 10m
1-15m
1 – 100m
2-10m
1-800m
Low Power
Yes
Yes
Yes
Yes
No
Price
$13.46
$9.96
$21.70
$21.00
$33.00
 Chose RN41 due to low cost, high range, and black box
functionality
 W T41 strong contender but expensive and drains battery
quickly
POWER SYSTEM OVERVIEW
 All components need 3.3V
 Around 500mA when
everything is going
 Power source needs to be
small and lightweight
 Rechargeable or easily
replicable power source
 One switching regulator
 3 AA Batteries held in a
battery holder
BROBOT’S PLATFORM
 Exact platform hasn’t been
determined
 Bluetooth antenna needs to
be protruding
 Small and lightweight
 Expandable/ Contractible
casing for easy traveling
ITEM WATCHING OVERVIEW
 Use computer vision techniques.
 Compare 2 images from dif ferent points in time
 Determine if there has been a significant amount of change
ALGORITHM EXPLANATION
 Store an “original” image
 Every ½ a second, take a new picture
 Compare new picture with “original”
 If the images differ by too much, sound alarm
 Every 15 seconds replace “original” with the newest
picture taken
PSEUDOCODE
APP SUMMARY
 Android application’s main focus is to alert the user
if something has been stolen
 Picture of BroBot’s current view will be refreshed for
the user to view at any time
 App will vibrate to alert the user if something is
taken
ANDROID VS IOS
 Android represents a bigger market share
 Does not require a Mac to code
 Good APIs to interface with Bluetooth
APP DESIGN
 Initial screen shown upon startup
 If connection fails, user will see an
error
 If it succeeds…
 User will be taken to screen showing
BroBot’s field of vision
 When his sight is aligned properly,
press the button to start the item
watching software
 This button will be replaced with a
“Stop Watching” button, or a
“Silence Alarm” button if it is tripped
falsely.
BLUETOOTH CONNECTION
 Once Bluetooth connection is established, app opens an input
thread and output thread
 Output thread stays idle and waits for signals to be sent to
BroBot
 Input thread constantly looks for new pictures or information
from BroBot
 Bluetooth’s input stream buf fer reads in an array of bytes
 Combine these bytes and restore the original picture
SUCCESSES!
 Bluetooth module to terminal communication
 Items are bought
 Item watching algorithm done
 App GUI is done
DIFFICULTIES
 Camera shipping
 App Bluetooth Connection
 Converting byte array into viewable JPEG
 Enough time for testing for Item Watching
 Finalize power
ORIGINAL BUDGET
Item
Platform
STM Discovery Development Board
RN-41 Bluetooth Module
2 Megapixel camera
Printed Circuit Boards
Report Binding
Batteries
PVC supplies
Total
Price
$20.00
$14.90
$21.70
$18.99
$75.00
$15.00
$20
$20.00
$205.59
CURRENT SPENDING
Item
STM Discovery Development Board
RN-41 Bluetooth Module
MT9D111 Camera
Backup Camera
Report Binding
Total
Still $106.76 in our budget
Need:
Platform
Battery
PCB
Price
$0.00(Previously Owned)
$29.89
$18.99
$44.95
$5
$98.83
PLANS FOR SUCCESS
 App communicating with module by first week of February
 Bluetooth Module communicating with ARM processor by mid
February
 Camera communications finished by end of February
 Item watching program tested and working on a desktop by
end of February
 PCB designed and finished by early March
 Full app development finished by mid March
 Item watching program testing during March, finished by end
of March
 Full prototype testing during mid March and finished by early
April
PROGRESS CHART
Research
72
Design
78
Prototype
20
Testing
20
Total
48
0
20
40
Total Progress
60
80
100
OTHER CONSIDERATIONS
 Siren implementation
 Video stream
QUESTIONS?