1. ROOM OCCUPANCY INDICATOR
Abeer Zidan
Fatima Al-sayyied
Kwan

2. INTRODUCTION
Our senior design project aims to create a functional system where the number of people in a room can be determined based on tabulating people entering and exiting a room.
Kwan

3. OUR OBJECTIVES
Accurately sense whether or not someone enters or exits a room through ultrasonic sensors
Keep/Update count value in the microcontroller
Transmit and receive the count value wirelessly
Convert count value so a computer can understand it using MAX-232/RS-232
Display count value on the computer
Rock

4. Applications
• Easy way to know the number of people in a room or building
• Connects settings of heating, lighting, and other utilities to room occupancy
• Assists situations where evacuation may be necessary, e.g. bomb threats, fire alarms, etc.
• Improves time management, e.g. hotel housekeepers can skip occupied rooms

5. BENEFITS & FEATURES Low overall cost Easy to use
Wireless transmission of occupancy data
Ability to toggle between two counting modes
Mode I: keeps track of total number of people in room (adds if people enter, subtracts if people leave)
Mode II: keeps track of highest count (adds if people enter, does not subtract if people leave)
Sunil

6. REVIEW ORIGINAL DESIGN
Sunil

7. ORIGINAL DESIGN Room A Room B Master Room Channel 0 Channel 1 Wireless
5 people
Room B
4 people
Master Room
Room A 5 people
Room B 4 people
Channel 0
Channel 1
Wireless
Communication
Sensors -> Pic -> Transmitter -> Receiver -> Pic -> MAX -> RS -> Display
Sunil

8. PROJECT BUILD AND FUNCTIONAL TESTS
Ultrasonic Sensors
Microcontroller
Wireless system
MAX-232/RS-232
Display ON PC
Sunil

9. SUB PROJECTS
Sensor System: This consisted of two adjacent ultrasonic sensors. The sensors sent out waves and if asignal arrived back to its respective sensor faster than normal, then the appropriate sensor detected aperson.
PICs: The system had two PICs. One simply acted as an oscillating input for the sensors. It mimicked a 1Hz, 13% duty cycle signal that signaled the sensors to send out ultrasonic waves. The second PIC had the logic setup which determined the current count of people in the room.

10. CON.
Transmitter/Receiver System: This portion of our design wirelessly transferred the occupancy value from the first PIC to the MAX-232.
MAX-232/RS-232: The MAX-232 converted the signal that came from the receiver into a signal that the RS-232 could read. The RS-232 then fed this signal into the display.

11. BLOCK DIAGRAM SENSOR #2 MICROCRONTROLLER WIRELESS TRANSMITTER
WIRELESS RECEIVER
MAX-232
RS-232
SENSOR #1
PERSON
DISPLAY
TX MODULE
RX MODULE
Kwan

13. Sensor SRF08 The SRF08 appears as a set of 36 registers
Reg.0: read\ write ; read gives version of srf
write gives unit of measure
Reg.1: read; photo sensor gives a value from that represent light intensity
Reg.2: gives the distance

16. SENSOR DISTANCE & RANGE
22°
wall
y = ?
x = ?
x = ?
22°
22°
y = ?
wall
NOT PREFERRED
Kwan
PREFERRED
tan 22° = 0.4 ≥ x/(2y)
 x/y ≥ 0.8

19. MICROCONTROLLER Sunil (5V) (GRND) Master Clear/ PIC Reset
4 MHz oscillator
LED Output – For Testing
LED Output– For Testing
Count transmitted to wireless circuit
Switch Input – Mode Type of Count
Switch Input – Count Reset
Input – SCL
Sunil
Input SDA

20. Microcontrollor
Detect the current count of people in the room and make calculations on it and send it to Tx
This process was done by making a state machine in order to know previous input values and to handle the frequency issues involved in checking the sensors’ outputs.
The pic operates at two modes:
Default mode :room occupancy indicator(tracked current amount of people)
Secondary mode: total amount of people who entered a room over atime

21. STATE MACHINE STATE 0 (START) STATE 1 STATE 2 ENTRY (ADD 1) EXIT
00/11
STATE 0
(START)
01 (S1 on 1st)
10 (S2 on 1st)
00/11/01
00/11/10
STATE 1
STATE 2
10 (S2 on 2nd) 11
01 (S1 on 2nd)
Sunil
ENTRY
(ADD 1)
EXIT
(SUBTRACT 1)
unconditional
unconditional
TRANSITION
STATE
00/10/01

22. WIRELESS SYSTEM Xbee (ZigBee series 2 ;ZN or 2.5)transmitter
Xbee (ZigBee series 2 ;ZN or 2.5)receiver
. This is the very popular 2.4GHz XBee module
**transmitter take the output from the microcontroller and send it to the receiver.
Kwan

23. Features: It's used for both transmitting and receiving
It's used for both transmitting and receiving
Small size and low cost and low power consumption
Power down sleep current less than 10 micro A
Supply voltage 2.8 to 3.4 v
50mA( serial interface)
16-direct sequence channels
250kbps Max data rate
Frequency band 2.4 GHz
Indoor range\Urban range :133 ft (40 m)
Outdoor\ RF line of site range 400 ft (120 m)
Operating temperature : -40 c to 85 c
Built-in antenna( chip antenna, wire whip antenna, RF connector.)
Point-to point or mesh network

25. Design Notes: • Minimum connections: VCC, GND, DOUT & DIN
• Minimum connections to support firmware upgrades: VCC, GND, DIN, DOUT, RTS & DTR
• Signal Direction is specified with respect to the module
• Module includes a 30k Ohm resistor attached to RESET
• Unused pins should be left disconnected

27. DTR - "Data terminal ready" this is a flow control pin used to tell the XBee that the microcontroller or computer host is ready to communicate.
RST - this pin can be used to reset the XBee. By default it is pulled high by the 10K resistor under the module. To reset, pull this pin low.'
Ground - common ground for power and signal
CTS - "Clear to Send" this is a flow control pin that can be used to determine if there is data in the XBee input buffer ready to be read

28. RX - This is the XBee's serial recieve pin
RX - This is the XBee's serial recieve pin. Serial data is sent on this pin into the XBee to be transmitted wirelessly
TX - This it the XBee's serial transmit pin. Serial data is sent on this pin out of the XBee, after it has been transmitted wirelessly from another module
0 RTS - "Ready to Send" this is a flow control pin that can be used to tell the XBee to signal that the computer or microcontroller needs a break from reading serial data.

29. Serial Data
Data enters the module UART through the DIN (pin 3) as an asynchronous serial signal. The signal should idle high when no data is being transmitted. Each data byte consists of a start bit (low), 8 data bits (least significant bit first) and a stop bit (high). The following figure illustrates the serial bit pattern of data passing through the module.    

30. Max232 and RS-232 No Handshaking 1 CD Carrier Detect
2 RXD Receive Data
3 TXD Transmit Data
4 DTR Data Terminal Ready
5 GND Ground
6 DSR Data Set Ready
7 RTS Request to Send
8 CTS Clear To Send
9 RI Ring Indicator
Rock
No Handshaking

31. MAX-232/RS-232 INTERFACE
Rock

32. RECOMMENDATIONS
Include usage of infrared sensors to make sure humans are detected as opposed to inanimate objects.
TO solve the problems of the sensors; we can use (motion detection) camera.
Sunil

33. Questions?