Electroluminescent Cap Project
Team Members:Monica PereiraMonique PeregrinaLiang LiufuIfedayo Ogundana
Faculty Advisor/Reviewers:Dr. Michael FrankDr. Bing KwanDr. Rajendra Arora
Sponsored by:Albert Daci
Milestone # 2-Project Proposal
PROJECT MANAGEMENT
The Team & their Qualifications
Monica PereiraProject ManagerArea of expertise: advanced circuit design, electronics, power analysis.
Monique Peregrina Assistant Project Manager/Documentation CoordinatorArea of expertise: advanced circuit design, electronics, power analysis.
Liang LiufuTreasurerArea of expertise: advanced circuit design, electronics, computer architecture
Ifedayo OgundanaHead of ResearchArea of expertise: Microprocessors, Computer System Architecture, Digital Logics, and Digital Communications
Monica Pereira
Introduction/Overview of the Project
• The purpose of this project is to design an original cap that implements electroluminescent technology. This cap will consist of a panel with flashing capabilities and with a hidden internal circuit.
• Currently, there are a few similar designs in the market that implement electroluminescent wires, panels and tapes. However, the current designs have a bulky circuit while others have their wires and/or switches exposed in the back.
• The design proposed by this team, would implement small rechargeable batteries in order to reduce the size of the overall circuit and use small components in order to make the cap comfortable while providing a slim design.
• Each cap will implement a switch with three states (turn on, flash, turn off) and be provided with an internal circuit with water resistant capabilities. In addition, the cap will come with a mini-USB charger hidden underneath the bill of the cap.
Monica Pereira
Intended Use, Users & Operating Environment
USE: The cap is designed to be used for everyday activities. It will be required to resist exposure to dusty conditions as well as water, sweat and any other agents that may cause excessive dampness within the hat so that it can be worn while being outdoors or performing extraneous activities.
USERS: Any individual from almost any age range can use this product as long as he/she follows the guidelines stated in the user’s manual for handle and care.
OPERATING ENVIRONMENT: The prototype is required to operate under normal conditions since it is intended for regular use. The cap must resist light rain, sunlight exposure, plus any other factors that might follow during daily activities.
Monica Pereira
CONCEPT GENERATION & SELECTION
COMPONENT SELECTION
Approach
• The approach followed for selection is based mostly on the size, weight, and ease of implementation of each part, since all of our components must fit within the cap.
Design Components• Fitted baseball cap• LiPo rechargeable battery • Battery charger• 10cm x 10cm EL panel• 3V DC battery inverter• IC chip• Liquid Encapsulating epoxy resin
Cap Selection Approach• The selection of a cap was carefully done
based on its design since this determines how much room (within the inside of this hat) can be used for storing components.
• As requested by our sponsor, only fitted caps can be used.
Monica Pereira
Option 1: Fitted baseball Cap Benefits :• More comfortable for the consumer to wear • Has an easy and relaxed fittingDrawbacks:• Its lower crown may reduce allowed space to
conceal circuitry and • Its Curved bill makes it more difficult to attach
the switch and the battery charger in the bottom of the bill.
Monica Pereira
Option 2: Fitted Flat-bill Cap Benefits • Has a high crown which allows more
room to conceal the circuit without causing discomfort to the user.
• Its flat bill allows better integration of a switch and mini-USB charger on the front of the hat.
Drawbacks:• Style may not attract certain users
Monica Pereira
Battery Selection Objectives • Battery must power the circuit while remaining small and lightweight
enough to not hinder the cap.
Approach• Several factors must be taken into consideration when choosing this
component: weight, size, voltage output, capacity, chemical composition, and availability.
Liang Liufu
PRT-00339 Lithium Polymer Battery
Specifications • Dimensions: 0.23” x 1.32” x 1.86”
(5.84x34x47mm)• Weight: 0.77oz (22g)• Nominal Capacity: 1000mAh• Nominal Voltage: 3.7V• Charge cut-off voltage: 4.20V• Standard discharge current 0.2 C
• Max discharge Current: 2C• Discharge cut-off voltage: 2.75V• Cell Voltage: 3.7-3.9V• Impedance: <300 Ohms
Liang Liufu
PRT-00339 BatteryBenefits• Small and lightweight allows for good implementation into cap
• Rectangular size allows for easy mounting onto cap without need for battery housing
• Rechargeable: eliminates the need to buy more batteries, saving money for the consumer
• Higher capacity allows for longer use per charge
• Low discharge rate allows for longer storage times before depletion (0.1% per month)
• Very Stable: No explosion or fire when over charged, over discharged, short circuited, extrusion, and thermal shock.
• Durable: vibration, collision, and dropping it does not affect performance.
Drawbacks • Requires a charger and not easily replaced.
• Slightly larger size might present slight problem in order to fit inside the cap.
• Extra charger creates an additional component that needs to be added onto the hatLiang Liufu
Li-Poly Charger Specifications • Regulated output voltage: 4.20V
• Precondition current ratio: 10
• Precondition voltage threshold ratio: 66.5
• Charge termination current ratio: 7.5
• Recharge voltage threshold ratio: 96.5
• Temperature range: -40C to +85C
• Dimensions: 29.4mm x 10.8mm
•Four voltage regulation options: 4.2v, 4.35v, 4.4v, 4.5v
•Programmable charge current: 15mA to 500mA
•Selectable Preconditioning: 10%, 20%, 40%, or disable
•Automatic Power Down
Liang Liufu
CR2032 AAA Lithium LR44 Alkaline PRT-00339
Size Diameter: 19.9mmHeight: 3mm
Diameter: 10.5mmHeight: 44mm
Diameter: 11.4mmHeight: 5.2mm
0.23” x 1.32” x 1.86” (5.84x34x47mm)
Weight 3 grams (0.1oz) 7.6g (0.3 oz) 1.75g 0.77oz (22g)
Capacity 240mAh 1250mAh 105mAh Nominal Capacity: 1000mAh
Nominal Voltage 3V 1.5V 1.5V 3.7V
Discharge Current 0.19mA 600mA 0.2mA 0.2C
Other Possible Battery Choices
Liang Liufu
Benefits • Much smaller board allows for easier integration into cap• Micro USB port is fairly common and can be easily recharged• Automatic power down prevents over charging
Drawbacks • Exposed chip: requires an extra step to encase the chip• Extra component that must be concealed within the cap
Li-Poly Charger
Liang Liufu
Other Possible Chargers
Li-Poly charger, 3.7v mini-USB JSTSpecifications:•5V input via mini-B USB connector•0.1” breakouts for battery, DC IN, and status LED•3.7V output to battery•Supports 10k NTC Thermistor which has been filled by a 10k resistor•0.2oz (5.7g)•Adjustable current by soldering a resistor•Dimensions: 1.3” x 1.4” x 0.3” (33 x 35 x 7mm)
Li-Poly charger for 3.7v cells, JST 2.0mm model USB-uLIPOSpecifications:•Regulated output voltage: 4.20V Precondition current ratio: 10•Precondition voltage threshold ratio: 66.5•Charge termination current ratio: 7.5•Recharge voltage threshold ratio: 96.5•Temperature range: -40 – 85C•Dimensions: 29.4mm x 10.8mm
Liang Liufu
EL Panel Specifications• Glow size: 10cm X 10cm (3.95" x 3.95")• Plastic Size: 10.4 cm x 10.4 cm (4.1" x 4.1"), about
0.5mm thick • Panel lifetime: >25000 hours • Operating voltage: 60-250VAC • Operating Frequency: 50-5000HZ • Current Draw: 0.14mA/cm2 (max) @ 110V / 400Hz • Initial Brightness: 75 cd/m2 • Operating Temperature: -50ᵒ C / 65ᵒ C • 45 nF per panel
Liang Liufu
Benefits• Ultra-thin material allows easy concealment within the cap• Flexibility allows panels to be stitched to the shape of the cap• High efficiency allows for maximum life of batteries• Low temperature makes it cool to the touch• Can be easily cut to the desired shape• Vibration and shock resistant allows it to withstand common wear• Can continue to operate even if puncturedDrawbacks • Cannot be folded: it cannot withstand being folded like a sheet of
paper• Uses more power than EL wires• The connection is not waterproof (it is only heat shrink)
EL Panels
Liang Liufu
Other EL material choicesEL Wire•Input voltage: 40-110VAC•Input frequency: 400-3000Hz•Electrical Current: <150mA•Twisting Angle: 30 degrees per meter•Bending Diameter: >10mm•Stretching Force: <1.5kg•Operating temperature: -10C – 60C•Operating humidity: <60%•Lifetime: 3000-6000 hours•Storage temperature: 5C – 35C•Storage humidity: <30%
EL Tape•Size: 100 cm x 1.5 cm about 1mm thick. The glowing part is 1cm wide. •Panel lifetime: >25000 hours•Operating voltage: 60-250VAC•Operating Frequency: 50-5000HZ•Current Draw: 0.14mA/cm2 (max) @ 110V / 400Hz•Initial Brightness: 85 cd/m2•Operating Temperature: -50 C / 65 C•~10 nF per meter
Liang Liufu
Battery Inverter Selection
Objectives• Select a battery inverter that can provide the necessary amount of AC
voltage and current to the EL panelApproach• The first goal is to find an inverter that is small in size. The inverter, as
with everything else, must fit easily within the confines of the cap.• The second goal is to find an inverter that can convert the voltage
from the battery to 110V AC voltage to power the EL panel.
Ifedayo Ogundana
Battery Inverter specificationsCR2032 ELI-IMC AA F10L20 CI-L3F25
Size 47mm X 23mm X 9mm
13 mm diameter x 10 mm height
87mm x 33mm x 19mm
105mm x 74mm x 41 mm
29mm x 29mm x 27 mm
Weight 11g 2.2g 21g 24.5g 28.35g
Frequency 1000Hz 2500Hz 1000Hz 2000Hz 2000/3000Hz
Power Supply Required
3V DC 3V or 1.5V DC 3V DC 9V DC 12V DC
Modes Off/on/blink None Off/on/blink Off/on/blink Off/on/blink
Ifedayo Ogundana
3 V ELI-IMC Battery Inverter Specifications • External 3V or 1,5V (+/- 20%) power supply (or
battery) needed• Total EL fiber length 0m-0.5m (0"-20")• Frequency: 2500 Hz• Size: 13 mm diameter x 10 mm height (0.5"
diameter x 0.4" height)• Weight: 2.2 g
Ifedayo Ogundana
3 V ELI-IMC Battery Inverter Benefits• Very small size and light weight• Can be used with battery and external power supply• Suitable for use with both EL wires and panels
Drawbacks• Low hum noise is produced during operation• No on/blink /off switch incorporated• Capable of lighting only a small length/area.
Ifedayo Ogundana
Objectives• Select a 555 Timer IC to control the
blinking of the logo.• The IC is required to set a frequency which
will allow the EL panel to blink.Approach• Size will be taken into consideration. • Minimal cost if also preferred
Timing IC Selection
Monique Peregrina
Timing IC SelectionModel 75555 (Advanced Linear Devices, Inc)
TLC555 LinCMOS Timer (TI)
Model NA555 (TI) Model LM555 timer IC (Intersil)
Supply Voltage 2 V ~ 10V 2 V ~ 15V 4.5V ~ 16V 2V ~ 18V
Package/Case 8-SOIC (0.154”, 3.90 mm width)
8-SOIC (0.154”, 3.90 mm width)
8-SOIC (0.154”, 3.90 mm width)
8-SOIC (0.154”, 3.90 mm width)
Frequency 2.5 MHz 2.1 MHz 100 kHz 1 MHz
Price $1.83 $0.30 /2,500 parts $0.11 / 2, 500 parts $0.78
Monique Peregrina
Model LM555 timer IC (Intersil)
Specifications• Type: 555 type, Timer/Oscillator (Single)
• Supply Voltage: 2 V ~ 18 V
• Current: 60µA
• Operating Temperature: 0ºC to 70ºC
• Package/Case: 8-SOIC (0.154”, 3.90mm width)
• Frequency: 1 MHz
Monique Peregrina
Model LM555 timer IC (Intersil)Benefits• Does not present a minimum unit order to
be purchased
Drawbacks • Unit price is higher than other brands
presented (for a single unit price is $0.78, for orders greater than 100 units the price drops to $0.38)
Monique Peregrina
Waterproofing/Insulating component Selection
Objectives• Select the best waterproofing and insulating material to encase the circuit within the
hat.
Approach• The first goal is that the material must be able to cover the entire circuit and remain
water resistant even under normal wear and tear.• The second goal is that it must be dielectric because it will prevent any electric
current from escaping the circuit which could ultimately cause harm to the consumer.
Monique Peregrina
Waterproofing/Insulating component Selection
Sugru Silicone Rubber
Turbo-Coat Acrylic Conformal Coating Spray
Liquid Encapsulating Epoxy Resin
Color Black or White Clear BlackCure Cycle 24 h 10 minutes 24 hDielectric Strength 398 V/mL 1000 V/mL 19.36 kV/mLPot Life 30 minutes none 60 minutes
Monique Peregrina
Liquid Encapsulating Epoxy Resin
Specifications • Color: black
• Pot life: 60 minutes
• Cure cycle: 24 hours at room temperature
• Viscosity: 11500 cps @ 20ºC
• Dielectric strength: 19.36 kV/mm
• Operating temperature range: -60ºC to 140ºC
Monique Peregrina
Benefits • Excellent electrical insulation properties
• Good storage stability
• Supports high temperatures
• Mechanical and impact resistance properties
Drawbacks• If exposed to great stress, the plastic may break
• It may shrink when it dries, stressing components in the circuitry
Liquid Encapsulating Epoxy Resin
Monique Peregrina
Proposed Design
Overall Circuit Design & Preliminary System Level
Design
Internal Circuit • To design the circuit itself, the battery will be
connected to both the charger as well as the switch.
• Switch will be connected to the inverter for ON state and also to the control circuit for BLINK state
• The inverter will then be connected to the panel.
• The entire circuit will be waterproofed and insulated
Monique Peregrina
Front View of Cap
• The logo will not exceed the dimensions of 3 inches by 3 inches.
• The logo will be cut out of the EL panel and stitched into the fabric.
Monique Peregrina
Internal View of Cap
• The switch will be located on the bill of the cap. It will be connected to the inverter and the timing IC.
• The timing IC and inverter will be on the same PCB. The front of the cap will provide the most space to conceal the two components.
• The battery charger will be placed on the front underside of the bill. It allows ease of access for the user to plug in the micro-USB connector.
• The battery component will be placed within the sweat band of the cap and concealed within the layer of fabric.
Monique Peregrina
Benefits of the Proposed Design • Comfort: circuit is small and unobtrusive to the user.
• Ease of use: only one button and a recharger at the bill of the cap will be visible allowing for simple use by consumer.
• Compact: by including as many components as possible into one small circuit design, space is saved.
• Unit cost: the individual cap will be relatively cheap to manufacture
• Waterproofness: with full coverage of the circuit in waterproof material, the risk of water damage will be minimal.
• Insulation: the waterproofing material is also a dielectric, which will insulate the user from the circuit.
Monique Peregrina
Drawbacks
• Durability: even though the circuit is designed to withstand light wear and tear due to common use, it is not designed to withstand rough use or extreme weather condition.
• Not machine washable
Monique Peregrina
Risk Assessment
• Uncertainties at Project Milestones• Required tool kit, components and materials to be used• Features and required capabilities to be incorporated• Incomplete knowledge and technical know-how of the
technology• Costs at project milestones
• Method and formulation challenges• Construction and Fabrication• Design Specifications• Imagination and Rationality• Technical feasibility
Ifedayo Ogundana
Risk Assessment (Cont.)
• Human Managerial factor• Physical loss and damage• Circuitry components malfunctioning
Ifedayo Ogundana
Schedule
Gantt Chart
Monica Pereira
Gantt Chart(Cont.)
Monica Pereira
Budget Estimate
Liang Liufu
Budget JustificationThe budget is made such that the following is assumed:• $30/hr base salary considering 12hours of work per week (both semesters)• Equal base salary for individuals working on this project• Addition of 29% of the personnel subtotal for fringe benefits• 45% of the total direct costs was added to account for the overhead costs• Expenses for the assembly of the internal circuit is included in extra costs
Liang Liufu
THANKS!
Questions?