Download Presentation - ECpE Senior Design

April 26th 2006
Project Team: May 06-19
Client
Iowa State University – Senior Design
Faculty Advisor
Dr. Degang J. Chen
Team Members
Wesley Adreon
Kong-Wei Soon
Andrew Cook
Dantrayl Smith
Presentation Agenda

Introductory Materials


End Product Design


Wesley Adreon
Circuit Layout


Dantrayl Smith
Andrew Cook
Resources & Conclusion

Kong-Wei Soon
Definitions












120 V AC – Refers to 120 volts alternating current. This is the
standard voltage for household outlets.
MPLAB – Programmer used to program microcontrollers.
IrED – Infrared light emitting diodes.
LED – Refers to light emitting diodes. A device that emits light
at the presence of current.
mA – Milliamperes.
PCB – Printed circuit board. Refers to what the circuit will be
placed on at time of production.
NiMH – Nickel metal hydride.
PICmicro® - Brand of microcontroller.
pSpice – A circuit design program.
RoHS compliant and Pb free – Restriction of use of
hazardous substances and lead free.
BJT – Bipolar junction transistor.
LDR – Light detecting resistor.
Acknowledgement


The design team would like to personally thank
our faculty advisor, Dr. Degang Chen Iowa State
University for giving us the opportunity to
create the product. The team would also like to
thank Dr. Chen for his technical advice, time,
and effort in overseeing the project.
Thanks also goes to Dr. Jacobson and Dr. Tuttle
for giving technical advice to the team.
The Purpose

Problem Statement


Design a nightlight that is competitive with the market
Problem Solution

Automatic Nightlight Features




Ability to detect motion on a 180 degree plane
Ability to distinguish between daytime and nighttime
Provides a delay before shutting off in case of a person returning to
the room
Operating Environment


Implemented within the hallway of a apartment or home
Intended for any people of any age who owns, rents or lives
in his/her own form of housing
Rise to a New Product

Assumptions/Limitations






The nightlight could be used all over the world
The final product could be built into homes
The angle of detection is limited to 180 degrees
The nightlight will only be able to operate between eighteen
and twenty-four hours without the 120 V AC power
Cost of device will be comparable to other nightlights on
the market
End-Product


Automated Nightlight
Instruction Manual
End Product Design

Approach Taken

Functional Requirements




Detection
Illumination
Battery Back Up
Design Constraints




Size
Budget
Cost
Low Power Consumption
Front View
Top View
LDR
Blue-green LED
Infrared Sensor
IrED
Approaches Considered

Motion Detection

Infrared Detection




Sound Detection




Cheap & Small in size
Sensing area is small
Not effected by ambient light
Sounds movements within the field
Devices are already in use
Component will be too large
Body Heat Detection



Pyroelectric device
Tune to detect human infrared signal
Cost of device is too much
Approaches Considered (Continued)

Illumination

Fluorescent




Solid State Devices (LED)




Commonly used
Long lifetime
The bulbs will be too large
Smaller
Lower power consumption
Difficult to replace
Incandescent Light Bulbs


Commonly used & readily available
High power consumption
Approaches Considered (Continued)

Control Circuit

Analog Circuits



Microcontroller



Use various circuits to dictate operating state
May increase size
Easy to manipulate operating state
Difficult to program
Ambient Light

Internal Timer



Operate at certain times of the day
Does not coincide with seasonal time change
Photocells


Detects ambient light
Not sensitive
Approaches Selected

Motion Detection

Infrared Detection


Illumination

Solid State Devices


Low cost & Easy to use & Size
Low lower consumption
Control Circuit

Microcontroller

Simplifies the overall circuit
Detailed Design

The Power Supply



Light Sensor



Infrared diode transmission
Infrared detection
Light Emitting Diodes


Phototransistor
Infrared


AC to DC step-down power
supply
Auxiliary battery
Visible illumination diodes
Microcontroller
Circuit Layout
Infrared Detection
Microcontroller
Power Supply
Ambient Light Detection
LED Light
Power Supply Design


Bridge rectifier
Voltage regulator



Set at constant 10V
Power switching
Second voltage
regulator
Light Sensor



LDR detector
BJT will determine
switching
Second switch to
define high or low
Infrared Emission and Detection
• Infrared LED’s turned on by microcontroller.
• Detection circuit looks for IR source.
• Uses a comparator and a offset bias.
LED’s
• 5 LED’s used
• LED’s attached to one pin of microcontroller
• Blue – green LED’s.
Microcontroller

Entire operation of the nightlight will be done
by the PIC microcontroller.
IR signals will be turned into a digital signal
 The signal will then be tested within the PIC and
appropriate outputs will given



Will use MPLAB from Microchip to program
Dataman programmer will be used to download
the program to the PIC microcontroller.
Testing Activities

Circuits


Building sub-circuits to implement to final design
Microcontroller
Developing source code to test
 Using simple designs to build


Overall Testing

After completion of all previous testing activities
Combining Parts



After successful testing, everything will be
placed onto PCB board.
The team will create PCB layout
The team will then transfer the layout to the
PCB board and attach all components
Testing Environment



Different users with different technical
knowledge
Different users with a different age range
Test in different hallway setups
Present Accomplishments
Project Deliverables
Completion
Percentage
Completed
Definition
Yes
100%
Technical Consideration
Yes
100%
Design Process
Yes
100%
Prototype Construction
Yes
100%
Product Testing
No
80%
Product Documentation
Yes
100%
Product Demonstration
No
80%
Product Reporting
Yes
100%
Project Schedule
Resources
Time consumption for various tasks in hour
Group
Members
A
B
C
D
E
F
G
H
Total
Wesley Adreon
6
28
81
34
11
13
6
11
190
Dantrayl Smith
8
23
79
32
13
13
6
10
184
Andrew Cook
8
27
82
33
15
14
7
11
197
Kong-Wei Soon
7
21
76
28
13
16
6
15
182
Total
29
99
318
127
52
56
25
47
753
Financial Requirements
Item
Cost by individual part
Cost by category
Project poster’s printing cost $ 0.00
(Free from Department)
$ 0.00
Poster Supplies
$ 42.00
$ 42.00
Electronics parts:
PCB board-2200 holes
PIC Microcontroller
Infrared LEDs (2)
Infrared Sensors (2)
LEDs (5)
9 V Battery
Power transformer
Bridge Rec.
BJT Switches (4)
Photo Transistor
Voltage Regulator
Passive Components
$ 4.29
$ 3.00
$ 1.00
$ 2.00
$ 2.00
$ 2.00
$ 3.00
$ 0.50
$ 2.00
$ 0.50
$ 1.00
$ 1.00
$ 2.00
$ 24.29
Plastic case
$12.00
$ 12.00
Totals
$ 78.29
Project Cost
Item
W/O labor
With Labor
Miscellaneous electronic parts
Poster Supplies
Plastic case
Subtotal
$ 24.29
$ 42.00
$ 12.00
$ 98.79
$ 24.29
$ 42.00
$ 12.00
$ 98.79
Labor rate at $ 11.50/hr
Wesley Adreon
Dantrayl Smith
Andrew Cook
Kong-Wei Soon
Subtotal
Total Project Cost
$ 2185.00
$ 2116.00
$ 2265.50
$ 2093.00
$ 8659.50
$ 78.29
$ 8737.79
Project Risk

Loss of a team member
 Tasks will be split up accordingly

Loss of documentation
 Entire team has copy of all reports

Unavailable Equipment
 Microcontroller programmer was inaccessible
 Incompatibility of programmer and microcontroller
Lessons Learned





Working as a team
Time Management
Communication
Experience with new devices
Microcontroller programming in assembly
Future Work



Automatic battery charging capability
User controllable light intensity
User defined sensitivity
Conclusion





The used of electronic home improvements devices have
became more common.
Electrical energy wastes caused by user’s habit of not turning
of appliances.
Two most appealing factors are ability to improve living
quality and effectively reduced electric consumption.
Battery backup system allows product to function with
interruption.
Marketable with competitive cost if produced in mass
quantity.