Designing a Voice Activated Compartmentalized Safe with Speech Processing using Matlab Final Presentation Amy Anderson Ernest Bryant Mike Joyner Collins Pratt December 7, 2007 Georgia Institute of Technology ECE 4007 Senior Design

Objective and Motivation Provide accessible and secure valuables storage for multiple users Demonstrate functionality without implementing safe construction standards Fulfill niche in voice security implementation in personal safes Market towards homeowners and small businesses

Project Description Cylindrical device Allows multiple storage compartments for each user Voice and password protected Automated process for opening and closing

Initial Design Objectives Build a wooden cylindrical compartmentalized safe prototype Allow access to each compartment through specific, user programmed voice password Develop Matlab program capable of identifying and verifying two specific speakers Develop GUI to allow user to easily configure and operate safe Interface computer and microcontroller through Matlab and serial cable Use microcontroller to control stepper motor that rotates safe top

Block Diagram of Safe Prototype

Software Design Overview Used Matlab for recognition algorithms and GUI Used assembly language for microcontroller program Speech processing algorithms used: –Mel Frequency Cepstral Coefficients –Vector Quantization Codebook

Software Design Diagram Password To Open System pass_box.m Store Word Features & Assign Compartment sgui1.m Compare Recorded Features With Stored Features sgui3.m Send Correct Compartment # Through Serial Port run1.m Change and Save Passwords pw.m Allow Password Entry to Manually Open Safe backup.m Allow For User to Chose Compartment user1.m, user2.m Send Correct Compartment # Through Serial Port run1.m Lock Out System Pass_box.m

Physical Design Modifications Stepper Motor moved to central location to eliminate the need for gearing Plexi-glass top replaced with foam-board due to torque limitations Compartment added due to construction configuration Microcontroller moved outside device for easier access while troubleshooting

Software Design Modifications Initial password required to access the system Separate text passwords created for compartments 1-3 and 4-6 for backup access Both passwords can be changed separately

Current Project Status Complete Design Objectives: Speaker and word recognition GUI Prototype compartment Matlab linking correctly with microcontroller Microcontroller turning motor Backup access password GUI Reprogrammable database and password function

Overall Project Performance User friendly GUI System characteristics Operational characteristics Speaker and word recognition accuracies

User Friendly GUI Enter Password to enter system Executing program initializes password GUI User enters preset password upon first use Password can be changed after initial system entry

User Friendly GUI 1. Configure compartments to specified word 2.Say item that you want retrieved 3. View the number of words stored 4. Clear all words stored for reconfiguration 5. Change password of first speaker 6. Change password of second speaker 7. Opens compartments with out saying words; password protected 8. Logs out of program

User Friendly GUI Password change GUI Allows user to change password upon entry of current password Each password is changed separately Enter current password Enter new password

User Friendly GUI Set word for specified Compartment Set length of recorded word

User Friendly GUI Backup Entry GUI Allows access to compartments should an error occur Password protected Click box corresponding to compartment Enter user Password

System Characteristics User can set voice recording time User can set and change passwords Configured to two users; could be adapted for up to six Backup password for error occurrence Initial password to enter system

Operational Characteristics Motor powered by 12V DC supply Time from word spoken to compartment opened:

Operational Characteristics Motor turn accuracy: –Dependant on amount of voltage supplied –Slight adjustments sometimes needed –Unable to determine numerical value

Word Recognition Accuracy 95% when correct word is spoken If random word is spoken, one compartment will still be randomly chosen Testing method: –Each group member programmed one word for each compartment –Each member then tested to see if word spoken would match correct compartment

Speaker Recognition Accuracy Testing method: –Each group member programmed 3 passwords –Used same 3 words for each member –After all words programmed, each member tested to see if their compartment would be picked correctly Experienced a few problems differentiating between speakers with similar voices characteristics and accents

Final Cost Retail estimate for final product: $1300 $168 profit for each unit sold, 12.9% profit

Future Work More sophisticated speech processing algorithms for better voice security Safe meets NFPA and UL standards LINUX box for stand alone capability Reed switches to increase motor accuracy Software streamlining Fix reprogramming problem