Multi-Sense Safety Sign Floor Signs of the Times, LLC Sponsor: Eddie Green Team Members: ECE-Michael Shepherd, Austin Brownlow, Eric Richter 1

Background According to OSHA –Slips and falls account for 15% of all accidental deaths 2 nd leading cause of deaths behind motor vehicles Approx. 12,000/year –One of the most frequently-reported insurance claims Approx. 25% of reported claims/year –Over 17% of all disabling occupational injuries result from falls Further need for slip and fall prevention 2

Background (cont.) The average workers’ compensation in 2003 for a slip/trip/fall was $20,228 –That’s $243 Million per year Current caution signs (if used) are inadequate –Most people have become desensitized to wet floor signs –Current signs receive a lack of attention 3

Floor Signs of the Times Founded by Eddie Green Created idea of multi-sense safety sign Developed several prototypes 4

One Original Prototype Sound Circuit Sensor Circuit Light Circuit 9V Battery 2 AA Batteries Li-ion 3.7V Rechargable Batter Open/Close Switch Light Refractor 5

Observations Not reliable –These parts were not designed for this system Not manufacturable –Not aesthetically pleasing Requires three separate power sources –Three separate circuits 6

Block Diagram 7

Power Supply 8

AA batteries Duracell MN1500 –Cost: 24 * –Quantity: 4 –1200 mAh Mounted in battery pack in series to reach 6V *Taken from 9

LED Assembly 10

LED Assembly Each assembly has 5 LEDs and resistors wired in parallel Assembly Wiring Schematic 11

LED Assembly Two assemblies per leg of floor sign Four assemblies in total –20 LEDs 12

Passive Infrared Sensor 13

Passive Infrared Sensor PIR –DYP-ME003 –Cost: $2.99 –Quantity: 2 –Detects motion and triggers lights and buzzer 14

Passive Infrared Sensor Features –Proximity of 5-7m (10-23 ft) –Operating Voltage: DC –100 ° visibility per side of sign –200 ° total visibility 15

Printed Circuit Board Assembly 16

PCB Assembly: Schematic 17

PCB Assembly: Eagle Layout 18

PCB Assembly: Printed Board 19

PCB Assembly: Buzzer Murata Self-driving buzzer –PKM24SPH3805 –Cost: $2.02 –Quantity: 1 –Sounds when motion detected 20

PCB Assembly: 555 Timer and Mode Switch 555 Timer –NE555S-13 –Cost: $0.42 –Quantity: 1 –Outputs to Buzzer Alarm and LED lights SPDT Mode Switch –OS –Cost: $0.40 –Quantity: 1 –Select the modes of operation 21

PCB Assembly: AND Chip AND Chip –SN74HC08 –Cost: $0.36 –Quantity: 1 –Provides logic to control output to LEDS and Buzzer 22

PCB Assembly: OR Chip OR Gate –SN74HC32 –Cost: $0.36 –Quantity: 1 –Provides logic to control output to LEDS and Buzzer 23

Breadboard Test Results Initial voltage: 6.15 V (nominal value is 6 V) Final voltage: 3.70 V (lights stop at 2.82 V) Time elapsed: 113 hours Rate of loss: (6.15 – 3.70) / 113 = 21.7 mV/hour Service life: (6 – 2.82)/ * 3/40 = 11 weeks 24

Prototype Cost Final Product Parts 1Rubbermaid Floor Sign$5.00 1Printed Circuit Board$5.00 1Resistor 620Ω$ Resistor 1kΩ$0.21 1Resistor 3.9kΩ$0.01 1Resistor 53kΩ$0.01 1Resistor 150kΩ$0.01 2Capacitor 0.01μ F $0.02 1Capacitor 4.7μF$0.01 1Transistor NPN$0.10 1MPD 4 Cell AA Battery Holder with Power Switch$1.99 2DYP-ME003 PIR Motion Sensor Module$5.98 1TI Quad 2-Input AND Gate$0.36 1TI Quad 2-Input OR Gate$ Cree LED 5mm White Clear 55Deg$4.80 1Diodes Inc Precision Timer$0.42 1Murata Electronics 3.8kHz Piezoelectric Buzzer$2.02 1C&K SPDT Switch$ Pin Power-Signal-Ground Cable Extension$ Perforated Bare Prototype Board$5.95 8Zinc Plated Steel Nut$0.47 8Philips Pan Head Screw$0.79 4Round Aluminum Spacer$0.76 1Header Connector Straight Through-Hole$0.75 Total:$

Manufacturing Cost Total Prototype Cost: $47.68 This cost is at individual pricing In production quantities, price would be cut in half –$

Recommendations Reverse-engineer PIR Sensor Printed Circuit board for LED Assembly Customizable LED/Buzzer frequency and light/sound magnitude Voice circuit –Verbal warnings vs. buzzer alarm –Multiple languages Moisture sensor –Able to detect moisture content –Automatically shut off when no moisture 27