Prototyping Home Automation Concepts

1. Class 2: Home Security Basics Prototyping Home Automation Concepts December 13, 2016 - Don Wilcher

2. Home Security Basics Topics • Home Security Elements • Example Systems and Devices: A Maker’s Perspective • Hands-On Project: Ultrasonic Detection and Alarm device

3. Home Security Elements A Do It Yourself (DIY) home security system should consist of the following elements. • A Central Monitoring System: a) verifies all alarms before dispatching authorities b) Communications can be via land line, celluar, Internet or combination. Source: https://www.electronichouse.com/home-security/anatomy-of-a-home-security-system/

4. Home Security Elements… • c) Optional two-way alarm verification enables monitoring personnel to listen in—only in the event of an alarm—and communicate with residents to verify the alarm before dispatching. • Motion Sensors • a) provide a second line of defense if an intruder gets past the door/window sensors. • b) Some sensors are referred to as PIRs, because they use passive infrared technology to detect the heat emitted by an intruder. • c) serve as occupancy sensors. A home security system dealer can program the system to turn off lights in the room if there is no activity for 5 minutes.

5. Home Security Elements… • Sinage • Window stickers and yard signs tell would-be intruders: Don’t even think about trespassing here. • Security Control Panel • As the hub of the home security system, the security panel • communicates with all of the devices including sensors (wired and • wireless), sirens, keypads, central monitoring station and the Internet. • Door/Window Sensors • a) The first line of protection, door/window sensors (sometimes • called “contacts”) detect the opening of doors and windows. • b) A system can be programmed to sound a chime when a door • or window is opened in an unarmed mode.

6. Home Security Elements… • Sirens a) Most systems have one tone for a burglar alarm and another tone for fire. b) Consider a system that also provides voice feedback so it can annunciate the specific issue: “Intrusion, master bedroom window.” c) A good system will have a siren time-out feature, typically 15 minutes, in the event the system should go off accidentally.

7. Home Security Elements…

8. Question 1 Motion Sensors provide a_____ line of defense if an intruder gets past the door/window sensors.

9. Example Systems and Devices: A Maker’s Perspective Basic latching alarm circuit The circuit can be used for a wide range of simple burglar or fire alarms as well as a for portable travel alarms. Source: http://www.nutsvolts.com/magazine/article/scr_principles_and_circuits

10. Example Systems and Devices: A Maker’s Perspective… PIR Sensor based Security System

11. Question 2 Identify the basic circuit.

12. Example Systems and Devices: A Maker’s Perspective… Fire Alarm circuit Source: http://www.circuitstoday.com/fire-alarm-circuit-2

13. Example Systems and Devices: A Maker’s Perspective… Fire Alarm circuit: Low Temperature Detected

14. Example Systems and Devices: A Maker’s Perspective… Fire Alarm circuit: High Temperature Detected

15. Example Systems and Devices: A Maker’s Perspective… Window/Door Sensing: How Does a Reed Switch Work?

16. Example Systems and Devices: A Maker’s Perspective Window/Door Sensor: Window/Door Closed S1= Reed Switch

17. Example Systems and Devices: A Maker’s Perspective… Window/Door Sensor: Window/Door Open S1= Reed Switch

18. Question 3 The electronic symbol shown slide 10 and identified as U1A is • a buffer • an operational amplifier • a common emitter amplifier • None of the above

19. Hands-On Project: Ultrasonic Detection and Alarm device

20. Hands-On Project Ultrasonic Detection and Buzzer-Alarm Project Objectives: • Learn about the GrovePi+ Shield Architecture a) Review of the circuit schematic diagram b) Review of electrical connectors and ports • Build a ultrasonic sensor actuated buzzer-alarm

21. Hands-On Project… GrovePi+ Shield: Partial Circuit Schematic

22. Question 4 What port is used to attach the Ultrasonic to GrovePi+’s Atmega328p microcontroller?

23. Hands-On Project… Source: https://www.dexterindustries.com/GrovePi/engineering/port-description/

24. Hands-On Project… Source: https://www.dexterindustries.com/GrovePi/engineering/port-description/

25. Hands-On Project… GrovePi+ Shield: Electrical Connectors Circuit Schematic Diagram

26. Hands-On Project… Ultrasonic Detection and Alarm Device Block Diagram

27. Hands-On Project: Ultrasonic Detection and Alarm Device Parts: GrovePi+ Board & Raspberry Pi Piezo-Buzzer and 4 Conductor Jumper wire Ultrasonic Sensor and 4 Conductor Jumper wire

28. Hands-On Project… Ultrasonic Detection and Alarm Device Wiring Diagram

29. Hands-On Project… Project Build Complete

30. Hands-On Project… Ultrasonic_And_Relay Python Code

31. Hands-On Project… Ultrasonic Detection and Alarm Device Python Code can be obtained from Dexter Industries github site: https://github.com/DexterInd/GrovePi

32. Question 5 In the Ultrasonic_And_Relay.py code, there is a variable assignment name used to control pin 2 for the Piezo Buzzer. Write a new variable assignment name to reflect the actual device wired to pin 2.

33. Hands-On Project… Open LXTerminal on the Raspberry Pi desktop and type the following directory and file commands to run the Python Ultrasonic_And_Relay code.

34. Hands-On Project… Congratulations!