Navigational Aid for a Blind Deaf Individual Konrad

Navigational Aid for a Blind Deaf Individual Konrad Ahlin Ben Davidson Bob Evans Jackson Lamp David Sachenik Rob Steigerwald David Yip

Design Goals Able to communicate effectively with deaf blind individuals Weight cannot exceed 4 ounces Must fit within a 4 x 2 x 1 inch volume Must be reasonably inconspicuous Will track position using RFID tags Power must last for ten twenty minute uses Cost to produce must not exceed $700 *antenna not counted in weight and size requirements

Concerns Volume Constraints Weight Constraints Heat Dissipation Attaching device to belt Program Accuracy PCB Design and Functionality

Size of Components Length (in) Width (in) Height (in) Inch cube Microcontroller 0. 551 0. 063 0. 019 Reader 2. 756 2. 087 0. 354 2. 038 Keypad 2. 008 2. 520 0. 276 1. 394 Battery 2. 09 1. 3 . 225 . 6113 Magnetometer 0. 9 0. 5 0. 1 0. 045

Size of Components Cont’ Components Diam Height Inch cube Side Motor 0. 394 0. 907 0. 110 Middle Motor 0. 472 0. 134 TOTAL VOLUME: 0. 023 3. 802

Outer Dimensions Component Length (in) Width (in) Height (in) Inch cube Main Case 2. 91 2. 25 Component Diam (in) Height (in) Inch cube Side Case 0. 5 1. 2 0. 197 Components Inch cube Total Volume: 9. 44 1. 38 9. 04

Weight of Components Microcontroller Weight (oz) TBD Reader 0. 441 Keypad TBD Magnetometer Battery 0. 028. 77 Side Motor 0. 229 Middle Motor 0. 060 Case Total TOTAL: 1. 18 3. 069

Power Consumption RFID Antenna Motors MCU Magnetometer Keypad Sum 1. 5796 W*hr 0. 021166667 W*hr 0. 047784 W*hr 0. 0913 W*hr 0. 083333333 W*hr 1. 823184 W*hr Battery is 3. 7 V, 1100 m. A*hr, 4. 01 W*hr

Heat Analysis – Hand Calculations Conduction Air Chip caused by air: Section of chip 0. 1” x 0. 1” A=6. 45*10 -6 m 2 Q= -KA (d. T/dx) QTotal=1. 6 W QPart =1. 6 W/210 = 0. 00762 W K= (about) 0. 0257 Wm-1 K-1 d. T/dx = Q/(-KA) d. T/dx = 0. 00762/(0. 0257*6. 45*10 -6) = 45969 deg. C/m =649 deg. F/in =64. 9 deg. F/0. 1 in

Heat – Experimental Results 140 Null hypothesis: Average temperature < 120 deg F Temp above Chip (deg F) 130 120 95% Confidence Alpha = 0. 05 Mean=113. 9 P-Value=1. 00 110 100 Fail to reject null hypothesis 90 80 0 5 10 15 20 Time (mins) Chip Temp (deg F) Case Air Temp (deg F) 25

Heat – Analytical Analysis Case thermal conductivity = 0. 2 Wm-1 K-1 Outside case temp set to 20 deg C Top of chip set to 54 deg Celsius (130 deg F) Bottom of chip insulated

5) Receive Map Info 11) Compare current to map 12) Record location history 2) Nearest Tag ID(s) 6) ID current location Navigation Loop 3) Destination 15) Monitor Hardware Health 13) Calculate path 7) Receive User Input 16) Calculate next movement instruction 17) Estimate Remaining Distance 4) User Input 19) Deliver Prompted Information to User Via Haptic Feedback 1) Region Map 18) Deliver Non-Prompted Information to User Via Haptic Feedback Functional Decomposition 8) Determine Orientation (Compass) 9) Charging Power 10) On. Board Power 14) Regulate Power (MCU: Define Interfaces with Power, User Input, Map Input, RFID Reader, Magnetometer, Output Drive Circuitry) Enclosure: Support & Manage Internal Components 20) Off Path 21) Hardware Health Connectivity of Modular Devices Battery Life 22) Movement Instructions Turn Destination Arrival 23) On Correct Path 24) Button Pushed 25) Estimated Remaining Distance

Final Design elements kept from previous years RFID tag and reader Keypad input Changes from previous years Vibratory haptic feedback Two motors for directional feedback One motor in base unit for input confirmation Modular belt design Two motors Base unit with keypad Separate antenna

Schematic of Build (outer case)

Schematic of Build (Battery)

Schematic of Build (RFID)

Schematic of Build (PCB)

Schematic of Build (Keypad)

Schematic of Build (Cover)

Schematic of Build (Motor Case)

Procedure of Build Week 1 Motor Testing (without case) Antenna Testing PCB Prototyping Board Week 2 Finalize design and build motor case Motor Tests (with case) Testing of Magnetometer Order Wiring and Belt Week 3 Order Base Case Test Keypad

Procedure of Build Cont’ Week 4 Test PCB Start design for part placement in case Order spacers and insulation for case Have developed program to start testing Week 5 Re-machine Case and continue fitting parts Test connections and interactions between MCU and other devices Order PCB Week 6 Test Durability of general design Finish Full Build Week 7 Application testing of device Week 8 – 10 Presentation Set up

Haptic Feedback Motors Input Confirmation Navigation Feedback Precision Haptic 10 mm Vibration Motor - 15 mm Type Pico Vibe 12 mm Vibration Motor - 3. 4 mm Type

Motor Tests Volt Step Testing Orientation Case Duty Testing Material Testing Cycle Testing Applied Force on Case

Motor Testing Results 310 -002 Voltage Current (m. A) Vibrating 0. 1 13. 6 no 0. 2 27. 3 no 0. 3 41 no 0. 4 47. 5 no 0. 5 51. 2 yes 0. 6 61. 2 yes 0. 7 76. 1 yes 0. 8 89. 4 yes 0. 9 101. 2 yes 1 114. 4 yes 1. 1 361. 5 yes 1. 2 400 yes 1. 3 x x Intensity light moderate high x Best Orientation N/A N/A N/A

User Inputs Command/ Request Guide to room #? ? ? Guide to Closest Bathroom Guide To Closest Water fountain Step 1 Step 3 * Step 2 Enter 6 Didgit room number * 1 * * 9 * Test Left Motor * 4 * Test Right Motor * 6 * Test Center Motor * 5 * ETA /On-Track * 0 * Cancel Request # # Enter Sleep Mode * # User Confirm * *

Outputs to User (Automated) Duration of Vibration Time Between Frequency Duty Output to User (s) Vibrations (s) (Hz) Cycle (%) Which Motor Turning Warning Pulse Turning Vibration Warning Battery Low Warning for Off_Track Destination Arrival Confirmation 2 N/A 3 4 4 1 N/A 1 1 N/A Repeat Test on entered testing instruction. Pulses and Turn Side Motor then turns off 0. 25 Continues to cycle until turn is accomplished or off track instruction is 75 Turn Side Motor activated 0. 2 Goes throught the cycle till use confirms they understand Both Side 80 Motors 0. 2 80 Center Motor 0. 5 Both side 50 Motors Goes throught the cycle till use confirms they understand Goes through the cycle till use confirms they are in the room

Outputs to User (User Generated) Duration of Time Between Frequency Duty Cycle Output to User Vibration (s) Vibrations (s) (Hz) (%) Which Motor Repeat ETA Active on user instruction. Pulses for the number of tags in list still to come Testing Vibrations Number Button Push Confirmation 0. 5 1 N/A 0. 5 50 Center N/A 1 Tested Motor 50 Center Test on entered testing instruction. Pulses and then turns off Vibrates for number of pulses equal to numeric number of button

Testing of Total Design Heat Internal Temperature must be less than 120 degrees Fahrenheit Drop Must be fully functional after a free fall drop from 3 feet Guidance Must accurately guide an individual from any location on the second floor of Building 9, to any designated location

Testing of Total Design (cont’) Battery Must Replacement take less than 1 minute Charge Time Charges Power Can in 8 hours or less Consumption Run for at least 200 minutes on 1 charge Removal Less and attachment of device than 1 minute

P 12015: Bill of Materials Type Component Part 900 MHz 8 d. Bi Flat Patch Antenna - 4 ft SMA Male Connecto Precision Haptic 10 mm Vibration Motor - 15 mm Type model 1 Precision Haptic 10 mm Vibration Motor - 15 mm Type model 2 Manufacturer Part # Quantity Unit Price Shipping Cost Total Cost ($) L-com Global Connectivity HG 908 P-SM 1 $54. 99 $10. 95$65. 94 Precision Microdrives 310 -001 3 $7. 56 $22. 68 Precision Microdrives 310 -002 2 $7. 56 $15. 12 Precision Microdrives Pololu Robotics & Electronics 312 -101 1 $6. 48 $17. 97$24. 45 Component Pico Vibe 12 mm Vibration Motor - 3. 4 mm Type 3 D Compass and Accelerometer Carrier with Voltage Regulators LSM 303 DLH 1 $19. 95 Component LSM 303 DLH Tilt Compensated Compass Chip ST Micro Electronics COM-09757 1 $6. 95 $3. 86$10. 81 Component Polymer Lithium Ion Battery - 1000 m. Ah Sparkfun Electronics PRT-00339 1 $11. 95 Component 16 -Bit Ultra-Low-Power Microcontroller Texas Instruments MSP 430 F 5438 A 1 $12. 13 Component Small Keypad Futurlec Electronics KEYPADSM 1 $2. 20 Component Skye. Module M 9 Skye. Tek M 9 V. 080527 Component PCB 1 $300. 00 Component IC BATT CHRGR LI+ 1 CELL MAXIM MAX 1555 EZK+TCT-ND 2 $2. 37 $4. 74 Component IC REG LDO 3. 3/ADJ 500 MA MAXIM MAX 1818 EUT 33+T 2 $3. 25 $6. 50 Component IC USB FS SERIAL UART FTDI FT 232 RL 2 $4. 50 $9. 00 Case Rod, ABS, Beige, 1 In Dia x 1 Ft L Grainger 1 ZBU 6 1 $8. 59 Case RIT - 1. 998 $10. 00 $19. 98 Component Total Cost: $538. 04 $4. 00$6. 20 $300. 00

Project Timeline

Risk Assessment MCU Lead Time Taking too long Motors Vibrating too had for leads Motors Burning Out Fails Drop Test Keypad Lead Time

? Questions