Monday, 23 April 2012

Week 14



Tittle

  • Combine all circuit:Heart rate measurement circuit and Stand Alone Arduino circuit

  • Make a suitable casing box for combine circuits


 Objective

  • To make casing for all complete circuits
  • To prepare slide show for the final year project presentation

Content/procedure

  • Complete circuit is matched with casing box to show to our accessor on the presentation final project day.
  • Before that, we need to show  all the complete works to our supervisor Sir Syazwan.Sir Syawan gives us an advice and supporting word.


Result/Analysis

  • We make a casing box that can catch our accessor interest and need to well prepared before the big day.

Conclusion

  • The presentation of final year project degree will be held at Gemilang Hall on Tuesday 23 April 2012.

Friday, 13 April 2012

Week 13


Tittle

  • Construct Stand Alone Arduino

Objective

  • To draw the PCB layout of the stand alone arduino
  • To construct the stand alone arduino circuit

Content/procedure

  • Found in the internet about stand alone arduino circuit.Stand alone arduino is been used for this project as a replacement of ready made arduino uno board
  • We draw the layout of stand alone first before next processing part


Result/Analysis

  • Stand alone arduino used 9 volt battery instead of using USB cable for ready made Arduino uno board.
  • The stand alone arduino function or working when the LED attached with circuit light up.After that,to ensured that its working we can try example provided for Arduino
Figure Shown that LED is light up when battery is connected to Stand Alone Arduino


 Conclusion

  • Because this project is final year project,so we decided not to used ready made Arduino Uno board.Stand alone arduino also can fuction like ready made arduino but the result cannot be display on the serial monitor.
Figure Shown "Heart Rate" is display at the LCD










Friday, 6 April 2012

Week 12


Tittle

  • Construct the heart rate circuit on PCB board


Objective
  • To draw PCB layout for the heart rate circuit
  • To construct the circuit on the PCB board


Content/procedure
  • At this stage,we need to draw the PCB layout of heart rate circuit using DipTrace.After that, we can do etching process and next put all the component on the PCB board before soldering process
  • We put the heart rate circuit on the PCB board to reduce noise causes  by jumper

Result/Analysis

  • We found that the result is same like on the breadboard.
  • When circuit is put on the PCB board, its look neat and orderly



Conclusion

  • We need to be careful when draw the circuit on the PCB layout because when mistakes occur on  the connected the component ,it will make all next process like etching disturbed.




Thursday, 29 March 2012

Week 11


Tittle
  • Try coding Arduino for heart rate measurement


Objective
  • To investigate and understand the accelerometer coding
  • To combine the accelerometer coding with heart rate coding


Content/procedure
  • At this stage we need to do many try and error.
  • Found in the internet, how to get the actual value of the accelerometer. Means from that, we need to have mathematical expression for the ADXL 335 accelerometer coding. We must considered the voltage supply value  to the accelerometer and the sensitivity of the accelerometer


Result/Analysis

  • After many try and error, finally we got the mathematical coding for the accelerometer.The mathematical shown below:

y/512.30*1.5-1.6)/0.33

  • For the threshold value ,the calculation is shown and will be explain in the report

Conclusion

  • The accelerometer coding will combine with heart rate coding. For the heart rate, we multiply the sensor reading with 60 second.
  • Full Arduino program code is in the final project report .

Thursday, 22 March 2012

Week 10



 Title

  • Testing the heart rate circuit




Objective

  • to observe the accuracy of accelerometer which act as a sensor,it will measure heart rate.
  • to investigate other component accuracy such as instrumentation amplifier,operational amplifier and timer




Content/procedure

  • After construct the circuit in week 9, tend to testing the circuit by using oscilloscope in order to show the results
  • from the oscilloscope we need to observe the peak or amplitude voltage that the accelerometer can reach.




Result/Analysis

  • When we tap or move the accelerometer ,signal will raised or reach certain peak.Amplitude is the maximum voltage reached by the signal. 

It is measured in volts, V.Peak voltage is another name for amplitude.

-Voltage is shown on the vertical y-axis and the scale is determined by the Y AMPLIFIER (VOLTS/CM) control. Voltage = distance in cm × volts/cm
-Time is shown on the horizontal x-axis and the scale is determined by the TIMEBASE (TIME/CM) control. Time = distance in cm × time/cm
I



 Conclusion
  • Testing circuit need more time in order to get the correct result.




Thursday, 15 March 2012

Week 9


Title

  • Construct circuit for heart rate measurement using accelerometer




Objective

  • to design the schematic diagram for heart rate circuit
  • to construct the accelerometer heart rate ciruit




Content/procedure
  • tried to combine and altered the schematic diagram from the internet to get the suitable heart rate circuit





Result/Analysis
  • After several alteration from 2 ECG circuits found in the internet, finally get the schematic diagram that suits with the accelerometer sensor.The schematic diagram is shown below:



 

Conclusion
  • This circuit is under testing.
  • The first stage testing is to get the peak of the accelerometer so then we can get the threshold value that been use for the programming part.Threshold value is for accelerometer that we used as a sensor.
  • Threshold as mentioned in the flow chart  is the way we used to get the heart rate in digital form.Accelerometer is moving up and down,so when the accelerometer is achieve above the the threshold value,it will triggered the next program code.







Thursday, 8 March 2012

Week 8


Title

  • Order and buy some component for heart rate circuit measurement



 Objective
  • To construct heart rate circuit measurement,so we need to but all the component needed


Content/procedure

  • Went to Jalan Pasar and order AD524AD.AD524 need to order first at SIM supplier but other component such LM741 and NE555 timer is available at Nixie



Result/Analysis

  • After deep research,AD524 AD precision instrumentation amplifier which act as preamplifier is suitable to be used in measurement of heart rate because its gain can be set to 1000 by short Pin 3 and Pin 11.

LM741- The 741 is connected as a source follower.  The output DC voltage of the AD524 is maintained to 3V.

NE555- The 555 monolithic timing circuit is a highly stable controller capable of producing accurate time delays, or oscillation. In the time delay mode of operation, the time is precisely controlled by one external resistor and capacitor.





 
 Conclusion
  • Circuit is developed on the breadboard
  • We testing the circuit by display the result at the oscilloscope
  • to power up the circuit,we used function generator first  for supply