1. Electronic Door Lock Senior Design Project Fall 1999 Team #15 Joseph Petrovic Robert Sanford Jon Benson, ECE 345 TA Prof. Gary Swenson, ECE 345 Director

2. Presentation Overview • Project Goals • Block Diagram • Design Specifics • Cost Analysis • Testing • Future Changes • Questions

3. Project Goals • Eliminate need for conventional locks and key cards • Enhance security • Low power consumption • Powerful • Highly reliable

4. Block Diagram

5. Design Specifics • 16-Button Keypad • 16-Key Encoder (MM74C922) • Wide voltage supply range: 3V to 15V • Low power consumption • Key bounce elimination with two capacitors • LED Display • Displays current mode of operation: locked, unlocked, or change password

6. Micro Controller (68HC12) • Low cost • High speed • 16-bit processing • 555 Timer (MC1455P1) • Easily adjustable timed output • Solid State Relay (W6125DSX-1) • Wide control voltage range: 3V to 32V • 25A current rating

7. Solenoid • Powerful • Pulling force: 9.4lbs at .125in 6.25lbs at .875in • No power consumption in locked position • Minimal rise in temperature during operation

8. Solenoid Door Wall Spring Inputs Locked • Locking Mechanism

9. Solenoid Door Wall Spring Inputs Unlocked

10. Cost Analysis

11. Labor Costs # hours * desired salary * 2.5 65 * $30 * 2.5 = $4875/person Total Labor Costs = $9750

12. Total Parts Cost: $139.02 • Total Labor Cost: $9750 • Total Project Cost: $9889.02

13. Testing • Micro controller communication with hardware • Power consumption tests of solenoid • Key bounce effects • Timing accuracy

14. Future Changes • Automatic shut-off switch • ROM chip instead of RAM chip • Simple push-button for unlocking door from inside • Manual override