FYP Presentation day(WEEK 14)

Alhamdulillah,today's presentation was done successfully.Although receive too much question from Miss Noey,i answered all of them without hesitate and full of confidence.Scared actually when heard that Miss Noey will assess my FYP but i mantain to stay calm.However,there is also fun part about my FYP presentation today where another my assesor,Sir Razif made some good humour.There is a part when we talk so much and he started to bored,he will make funny face and looked aroud him.And then when we just stop to make sure he is focusing on what we want to tell,he just say "ok,next".He also did not notify the poster that we put  on the wall eventhough we keep telling him and showing him about our poster.When he moved to the next booth besides us,then........ he notify the poster(=.=").As for i remember,he just assess us for about 5minutes.Sir Razif sure a funny man,although finished at our booth and went to the next booth,he still questioning us although we have already tell him the answer.(Sir y u no focus =.=").However,thanks to both of them for assessing us and give good feedback.  :)

This is our first assessor,Sir Razif.

Second assessor,Miss Noey.

Last but not least,thanks to my advisor ,Miss Nurul Fazlin binti Roslan for her hardwork ,trying to keep us on the track.Thanks because stay patient with our lazy and ignorant behaviour.Sorry for all our mistakes and we will learn from that.Thank you Miss.. :)

Preparing for the FYP Presentation(WEEK 14)

Tomorrow is my big day,which is my FYP Presentation Day.Held on Level 4 starting from 9.00am until 5.00pm.For the preparation,we need to wear a formal clothing and tight in.We also prepare a slide show and a video about swimming pool alarm for the assesors.Besides that,our booth will have a brochure and the poster about our FYP.

For the incoming question from the assesor,this night we do some research about the circuit,including the function of the components,circuit connections and others that have to do with the project.We also practising on introducing ourselves,training on answering possible question that assesor might ask,and also try to gain confidence for tomorrow presentation.

However,we will try to get enough sleep so tomorrow,we will be full of energy and more confidence facing the assesors.

Making a Poster (WEEK 14)

For the FYP poster,we have create a draft of it and email to miss Nurul Fazlin,our advisor.The poster have a background of blue colour to indicate water of swimming pool.The poster include of INTRODUCTION, AIM and OBJECTIVE,METHODOLOGY,DIAGRAM,ADVANTAGES and RESULT.This is our draft of FYP poster.

After that,we have receive feedback from miss,and the OFFICIAL FYP POSTER for our project are look like this:

Finishing the Swimming Pool Alarm(WEEK 13)

After the failure of making the circuit fully working,we have decided to move on to finishing the model of the project.We have buy 3 sugar paper(1 yellow paper,2 black paper),glu,double tape,boxes,cellotape and knife.For the swimming pool, we just use a small size container that we got from our home.

This model include a base,a swimming pool,fences and house.It takes 5hour to complete the construction of the model.Me and Fikri construct this model at my house.Although we didnt have much time,we manage to complete it in short duration of time.The house also looking good.The sensor also suit the swimming pool.The combination of the yellow and black colour paper bright up more the model.

After finish all the cutting,combining, and attaching the parts,the completed model look like this:

Although this model does not look very attractive,but we quite happy for this model.The yellow colour really will attract people.

Still Troubleshooting circuit.(WEEK 12)

In this week,we rushed back to level 4 to meet the technician to reprogram our PIC.Luckily,it was successful.Now we can try to troubleshoot the circuit again with the PIC functioning.The program that we use is from the EPE magazine.However,after putting the programmed PIC into the circuit,only the PIEZO SIREN and HOLD LED was working accordingly.We still did not know what is the problem that cause our circuit not completely functioning.

After a few advise from our friend and lecturer,we go meet the technician that program our PIC.And then she tell us that the program need to be compatible with the circuit which is the component that we used must be exactly the same with the component in the magazine.

As a conclusion,we can say that our circuit was partially function.Only PIEZO SIREN and HOLD LED was working correctly.When try to troubleshoot the circuit,we found no problem about the connection or about the soldering part.The current flowing in the circuit also correct.But the programmed PIC was incompatible with this circuit so its not fully working correctly.

Troubleshoot(WEEK 11)

After finishing constructing and soldering the circuit,we troubleshoot it to detect any problems.At the beginning,from our point of view,the circuit are well constructed.A few part of the circuit are functioning.Still,we have a problem about the LEDs and PIEZO SIREN.Both of it doesnt give out any output.After a few correction were made,the LEDs and PIEZO SIREN are functioning.But,we still did not test the circuit to its main function.This is because we did not programmed the PIC yet.


In the same week,we go to level 4 and meet the technician and ask them to programmed our PIC.After that,we put it to the test.Firstly,the siren are working well,one LEDs are working and others are not.And then suddenly,all of that turn off.After a few inspection,we found that the PIC was burned.Without any other PIC for our backup,we rushed back to Jalan Pasar and buy a new PIC.

BUYING THE CASING FOR THE BOARD.(WEEK 10)

After finishing constructing and soldering the board,we need to find the case for the board.The casing is need to be weatherproof so it will keep the board nice and dry.The case for the swimming pool alarm are buy at Jalan Pasar.

This case is for the pressure sensor.This case is different compare to the one in the magazine because the case in the magazine are not sold in Malaysia.This case is alot more bigger in size but also weatherproof.The cost of this case is RM15.00.

This case is for the swimming pool alarm circuit.This case is available at Jalan Pasar.It is weatherproof,long-lasting and can withstand high temperature.The cost of this case is RM30.00.

Constructing Circuit and Soldering component.(WEEK 9)

This time,we start putting the component on the board one by one.But we having a problem when putting the IC socket on the board because the gap between IC's leg is quite small.Still,we manage to overcome the problem.

After finish putting all the component on the board,we then start soldering all the components.During solder,we had encountered some problem,which is when we try to solder some components's leg,its was accidentally connected with others component's leg.To overcome this problem,we use sucker.

Drilling the UV board.(week 8)

Borrowing the drill from our friend,we start drilling the board but the drill bit was blunt.So,we had to go buy  a new drill bit at hardware shop.After that,we continue drilling the board until all the hole that needs to be drill is finish.

ETCHING NEW BOARD.(WEEK 7)

On the week 7,we have already buy a new UV board,so that we can continue where we had stopped last week.This time,we manage to make a perfect board without having any dificulties.The etching process take time of 1hour to complete because we had to refill the echant liquid.

ETCHING.(WEEK 6)

Thursday on Week 6,we go to etching our PCB UV board.First,we had to print out the PCB layout of the swimming pool alarm.Then,we scan the printout onto the UV board.We had done the task but make a mistake which is we had print on the wrong side of the board.So,to overcome this problem,we had to buy new board and start all over again.

About the IC-INSTRUMENTATION AMPLIFIERS(WEEK 6)

Last week,we bought two IC(LMC6064n) at Jalan Pasar.This IC is a quad op amplifier.The datasheet is given below.

This type of IC is very rare.This IC we need to order from Singapore because shop at Malaysia does not have this type of sensor.We bought two of these but we just use only one.The other one is for spare part.

More about components~(WEEK 5)

This is our components that we have bought from Jalan Pasar.

The most expensive component is our pressure sensor MPX2010DP.Cost around RM67.00 including courier.We need to order from Singapore because Malaysia doesnt have this type of sensor sold in shop.

Part and Component lists(WEEK 4)

1. 1 PC board, code 762, available from the EPE PCB Service, size102mm × 77mm
2. 1 IP65 sealed polycarbonateenclosure with clear lid, size 115mm × 90mm × 55mm (Jaycar HB-6246 or equivalent)
3. 1 IP65 sealed ABS case, 64mm × 58mm × 35mm
4. 1 sheet 18g of aluminium, size 26mm × 31mm
5. 1 12V 400mA DC adaptor
6. 1 piezo siren (Jaycar Cat. LA5308 or LA5256)
7. 1 piezo siren as above (optional)
8. 1 MPX2010DP Freescale Semiconductor pressuresensor (Jaycar ZD-1904 or equivalent) (Sensor1)
9. 1 SPST waterproof momentary switch (Jaycar SP-0732 or equivalent) (S1)
10. 2 SPST micro tactile switches (Jaycar SP-0600 or equivalent)(S2,S3)
11. 1 BCD DIL rotary switch (0-F) (Jaycar SR-1220 or equivalent) (BCD1)
12. 5 2-way PC-mount screw terminals with 5mm or 5.08mm spacing
13. 1 2.5mm DC panel socket 
14. 4 3-6.5mm diameter IP68 waterproof cable glands
15. 1 2-way pin header, 2.54mm spacing
16. 1 18-pin DIL IC socket
17. 2 M3 × 20mm screws
18. 6 M3 × 6mm screws
19. 4 M3 nuts
20. 3 PC stakes
21. 1 150mm length of medium duty hookup wire
22. 1 30mm length of 0.8mm tinned copper wire
23. 1 length of 2-pair (4-wire) telephone sheathed cable or 4-core alarm cable (to suit)
24. 2 100mm cable ties
25. 1 150mm length of 3mm ID (5mm OD) vinyl tube
26. 1 145mm length of 5mm ID (6mm OD) metal tubing

Semiconductors

1. 1 LMC6064IN quad op amp (IC1)
2. 1 PIC16F88-I/P preprogrammed microcontroller (IC2)
3. 2 BC337 NPN transistors (Q1,Q2)
4. 3 1N4004 1A diodes (D1-D3)
5. 1 16V 1W Zener diode (ZD1)
6. 1 5mm green LED (LED1)
7. 2 5mm red LED (LED2,LED3)

Capacitors

1. 2 470mF 16V PC radial elect.
2. 5 100mF 16V PC radial elect.
3. 3 10mF 16V PC radial elect.
4. 2 1mF NP radial elect.
5. 1 100nF MKT polyester
6. 2 470pF ceramic

Resistors (0.25W 1% metal film)

1. 2 470kW 2 22kW
2. 1 220kW 3 2.2kW
3. 2 39kW 6 1kW
4. 2 27kW 2 10W
5. 1 10kW horizontal trimpot (VR1)

Circuit Diagram Of Swimming Pool Alarm~(WEEK 4)

In this circuit diagram,there are the pressure sensor, an instrumentation amplifier and a PIC microcontroller, plus associated switches, LEDs and other components.Sensor 1 has differential outputs at pins 2 and 4. With the same pressure at both ports, pins 2 and 4 are nominally at the same voltage; ie, 2.5V. If the pressure at port 1 increases compared to port 2, pin 2 rises and pin 4 falls. The change in voltage is quite small – around 1mV for a 1kPa pressure difference. However, the actual voltage change with typical wave movement is only around 200mV,so we need to amplify this signal using instrumentation amplifier IC1.Since we are concerned with wave movements (pressure variations) rather than the absolute pressure levels, the output from the sensor is AC-coupled via 1mF non-polarised capacitors to op amps IC1a and IC1b. The non-inverting inputs of IC1a and IC1b (pins 3 and 5 respectively) are biased via 470kW resistors to a +2.5V reference, derived using two 2.2kW resistors and a 100mF capacitor.IC1a and IC1b are set up as non inverting amplifiers with 39kW feedback resistors and a single 10W resistor between their inverting inputs. A 470pF capacitor across the 39kW resistors rolls off signals above about 8.7kHz, and this prevents possible oscillation. The gains of IC1a and IC1b are each 1 + 39kW/10W, or close enough to 3900.The outputs of IC1a and IC1b are summed in differential amplifier IC1c, which effectively adds the two outputs together. IC1c’s gain is 2 × 27kW/22kW, or 2.45 (for the two outputs), so the overall gain is 3900 × 2.45 or 9555.


Rain Filtering:

IC1c’s output is filtered using a 2.2kW resistor and a 10mF capacitor to remove high-frequency signals above 7.2Hz. This prevents alarm triggering due to the detection of rain falling on the pool. IC1c also shifts the DC level of the output signal. This is done by feeding it with an offset voltage from IC1d, viathe 27kW resistor from pin 14. IC1d obtains its reference voltage from a pulse width modulated (PWM) signal from PIC micro IC2. This signal swings from 0V to 5V at a frequency of 490Hz, and has a duty cycle of about
50%. The PWM signal is filtered using a 220kW resistor and a 10mF capacitor, and is fed to pin 12 of IC1d. The PWM signal is adjusted automatically during calibration so that IC1c’s output is at 2.5V when there is no signal from Sensor 1.

Microcontroller:

The PIC16F88-I/P microcontroller (IC2) processes the signal from IC1c and drives the alarm and the Hold, Status and Alarm LEDs. IC2 also monitors inputs at RB1, RB2 and RB3 for the switches, the linking options at RA2, the RB4 to RB7 inputs for BCD1 and the voltage at the wiper of trimpot VR1. Output RA7 drives the flashing Alarm LED, while output RA6 drives transistors Q1 and Q2, which are the siren drivers. Trimpot VR1 is monitored by the AN4 input and its wiper voltage is converted to a digital value from 0 to 255 for its 0V to 5V range, to give a timeout period in minutes. This value is placed in a counter that is decremented every 1.18s until it reaches zero and the alarm goes off. Hold switch S1 connects to the RB3 input, which is normally held high (+5V) via an internal pull-up resistor. When S1 closes, IC2 responds by altering the mode from Hold to Monitor, or from Monitor to Hold. Output RA1 drives the Hold LED via a 1kW resistor. Output RA0 drives Status LED 2 via a 1kW resistor. LED2 lights during the quiescent set and Alarm set procedures. If LED2 is flashing, it indicates levels that are over the quiescent setting. Switches S2 (Quiescent Set) and S3 (Alarm Set) are monitored by the RB1and RB2 inputs. Pressing S2 or S3 starts
the program in IC2. This monitors the AN3 input and calculates the voltage range encountered for a period of 10s. It does this by monitoring the AN3 input every 100ms and storing the level in memory. After sampling for 10s,it finds the minimum and maximum values and subtracts the minimum from the maximum to derive the span range. This value is then multiplied by 95% for the Alarm level, and 105% for the Quiescent level. The lower alarm level provides for a small amount of leeway in pool movement to sound the alarm. The higher quiescent setting of 105% is so that the quiescent level for the pool will normally be less than this. The resulting values are then used to check for quiescent or alarm levels at the AN3 input. Whether or not to return to Hold from monitoring is selected with the linking at input RA2. RA2 is pulled high with the link in LK2 position and low with the link in LK1. Rotary switch BCD1 selects the monitor return period. When BCD1 is in position 0, all the switches are open and the RB4 to RB7 inputs are pulled high via internal pull-up resistors. This setting is for a ‘no-return to monitoring’ from hold. Other settings of the BCD switch will pull at least one of the RB4-RB7 lines to ground via its common pin, and select a time period.


PWM Signal:

As already noted, the CCP1 output at IC2 pin 6 produces the PWM signal. It is initially preset so that the output of IC1c is nominally at +2.5V. However, because of manufacturing tolerances in IC1, the output could vary and so there is a setup (to set the output to 2.5V). Pressing switch S2 before power is applied to the circuit runs this procedure. The program within IC2 then adjusts the PWM percentage so that the reading at port AN3 is at +2.5V. This process takes about 60s. The new PWM value is then stored and used every time the pool alarm is powered up. IC2 operates at 500kHz using an internal oscillator, and is run from a 5V supply derived from regulator REG1.

A Good Example~ (WEEK 3)

click me :)

This video show comparison between two alarm.One with foolproof alarm,and the other one without foolproof alarm.

How its Work?(WEEK 2)

Fig.1in the form of block diagram.Pressure variations due to changes in the water level are detected  by Sensor 1.Its weak output is amplified and then processed by the PIC microcontroller,which controls the alarms and drive the LEDs status.

It uses a pressure sensor to detect sudden increases in water depth, as happens when an object falls into the pool creating waves.The unit is built in two sections, each in a weatherproof box. One houses the sensor, while a second, which we have dubbed the Pool Alarm box, houses the PIC-controlled alarm circuit. The two are connected via a 4-way cable.The cable can be run underground across to the pool sensor box. Inside the sensor box is a pressure sensor. This measures the water pressure variations in the pool due to waves, and sets off an alarm if these variations reach a preset level. The sensor box has a thin tube emerging from it. The box is placed so that the probe tip is about 60mm to 90mm under water. This sensor box can be secured to a pool ladder or fixed to the side of the pool.

 Fig. 2,this cross section diagram  shows the internal structure  of the MPX-2010dp pressure sensor.The strain gauge varies its resistance according to the applied load.P1 and P2 are the two port openings.



The pool alarm is plugpack-powered, so it needs to be located near to the mains. Complete safety from the mains power is provided first by the isolation given by the plugpack and second, by the fact that there is no electrical contact with the water itself.



Additional features:


Most prominent on the main alarm box is a weatherproof pushbutton ‘Hold’ switch. This is used to set the operating mode of the alarm. When powered up, the alarm is initially set to its normal monitor mode, where it checks for pool wave movement. It takes about 10 seconds after power up to begin monitoring, and during this time, the green ‘Hold’ LED remains lit.After the 10 seconds, the LED flashes briefly every 1.5 seconds, indicating that the alarm is in the monitor mode.If the alarm senses that the pool wavemovement is sufficient, it will sound the alarm. The alarm period can be varied from between zero and five minutes, with typical settings around the 30s to 3-minute range. During the alarm period, an Alarm LED flashes on andoff at five times per second. The alarm siren can be stopped at any time by pressing the Hold switch. This will also stop the Alarm LED flashing. The Hold LED will also stop flashing, but unlike the Alarm LED, it will remain constantly on. The Pool Alarm is now in the Hold mode, where the alarm will not sound. However, the Alarm LED will flash whenever wave movement is above the alarm threshold. The hold mode is used when the pool is in use.

Wave movement:
The degree of wave movement required to set off the alarm can be calibrated to suit your pool. This is done by dropping a weighted bucket into the pool (simulating a small child falling into  water) and pressing the alarm level switch (on the PC board). The Pool Alarm will monitor the wave movement over a 10s period, and set up the level required for the alarm. During this calibration period, a ‘Status’ LED will be lit. A second quiescent level can also be calibrated into the Pool Alarm. This level is the wave movement within the pool when no-one is in it, but with a light breeze blowing and perhaps the filter running (normal filter running should not trigger the alarm). In practice, the level is calibrated under these conditions (when a reasonable wind is blowing) by pressing the Quiescent Level calibration switch. The alarm then monitors wave movement for 10 seconds and stores the level. During this calibration period, the Status LED is lit. Quiescent level calibration allows the Pool Alarm to provide extra features. First, it allows the mode to return from the Hold to the monitor mode automatically. So when the pool is being used, the Hold switch is pressed to set the Pool Alarm to the Hold mode so that the alarm will not sound. However, during this time, the alarm continues to monitor the wave movement.During pool use, the wave movement will continue to be over the quiescent level and the alarm will remain in the Hold mode. When the pool is not in use, wave movement within the pool will settle to below the quiescent level. In this case, the alarm will change from Hold mode to Monitor mode, after a preset period of ‘no pool’ activity. The period of inactivity can be adjusted to allow for the way the pool is used. If the pool is often vacant for a short time before it is used again, the period can be made sufficiently long to prevent the return to Monitor happening in that time period. The adjustment range is from 1.25 to 75 minutes. One setting prevents the monitor return function. The change from Hold to Monitor and from Monitor to Hold can also be toggled with the Hold pushbutton switch. The Hold LED then flashes for Monitor and is continuously lit for the Hold mode. During the monitoring mode, windy conditions may cause wave movement that could exceed the quiescent level but may be below the alarm level. The Pool Alarm has an option that can return it to the Hold mode if the quiescent level is exceeded for 30 seconds without the alarm level being exceeded. This feature is included to prevent false alarms from the siren in windy weather. The Pool Alarm will then return to the monitoring mode after the wave movement has reduced to below the quiescent level. Should the alarm sound and time out before the Hold switch is pressed, the alarm will return to Hold after the alarm period expires. The ‘return to hold’ option can be enabled or disabled with a jumper pin selection. Just which option you select depends on your pool and whether it is subject to windy conditions. Protected pools may not need the ‘return-to-hold’ feature. This is a compromise between preventing false alarms and providing continuous pool protection.


Pressure sensor:

An air-pressure sensor, the MPX2010DP manufactured by Freescale Semiconductor, is used to measure wave movement. Its internal arrangement is shown in Fig.2. The sensor comprises a strain gauge that provides a resistance variation with applied load. In this case,the load is the air pressure exerted on the gauge due to a tube inserted into the pool. The sensor is called a differential type because it measures the difference in pressure between one port and the other. For our application, we use Port 1, which has a silicone gel protective layer to prevent moisture affecting the strain gauge element. Port 2 is left disconnected and is vented to the inside of the enclosure.

Features of Swimming Pool Alarm.(WEEK 1)

Features:

• Monitors wave height caused by any disturbance in the pool.
• Adjustable quiescent and alarm wave levels. 
• adjustable alarm period.
• Pushbutton switch for hold/monitors.
  -Hold modes gives visual but silent alarm(for testing or attended pool use)
  -Monitors modes gives visual and audible alarm(for unoccupied pool)
• Automatic return to monitor modes after pool water settles.
• Adjustable return to monitor period.
• Optional set-to-hold mode with pool turbulence preventing false alarm.
• Wheaterproof housing.
• Can drive two alarm sirens.
• Plugpack powered.
• Suits all pool where the top water level is below pool edge.

Introduction of Swimming Pool Alarm(WEEK 1)

For this Final Year Project,the project that we have choose is SWIMMING POOL ALARM.Chosen from EPE magazine,this project is an alert system for swimming pool.As we all know,swimming pool is a dangerous place for toddlers.Although swimming pools nowadays were guard by fences,there is always a posibility that a toddlers will find a way to get through.So,while fences may appear as a pool secure,they are never foolproof.As a second line defense,one that warns if someone falls into the pool,can literally be the difference between life and death.

A way to add a secondary defense is with swimming pool alarm.The type of pool alarm described here monitors the amount of pool water movement and sounds an  alarm when this exceeds a preset level.There might be in case of wind that create the water disturbance.But,with this alarm,you can set to a level which ignores typical wind movement and sound the alarm when exceed the level(when someone falls into).