ROOM OCCUPANCY INDICATOR Abeer Zidan Fatima Al-sayyied Kwan

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

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

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

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

REVIEW ORIGINAL DESIGN Sunil

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

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

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.

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.

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

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 0-255 that represent light intensity Reg.2: gives the distance

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

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

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

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

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

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 3.3V @ 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

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

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

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.

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.    

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

MAX-232/RS-232 INTERFACE Rock

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

Questions?