Lab2Final.pdf - SIGNAL CONDITIONING MENG 3210/3211...

Info icon This preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: SIGNAL CONDITIONING MENG 3210/3211 LABORATORY REPORT TEAM-­‐DAQ REPORT SUBMITTED BY: ROBERTO GONZALEZ __________________________. JULIAN PEREZ __________________________. YOVANI ZELAYA __________________________. JUSTIN SWAIN __________________________. MOUSTAPHA DIABY __________________________. SAMUEL ADEBOLA __________________________. We certify that the narrative, diagrams, figures, tables, calculations, and analysis in this report are our own work. DATE EXPERIMENT PERFORMED: OCT. 23, 2013 DATE REPORT DUE: NOV. 3, 2013 DATE REPORT SUBMITTED: NOV. 3, 2013 MECHANICAL ENGINEERING DEPARTMENT COLLEGE OF ENGINEERING AND COMPUTER SCIENCE THE UNIVERSITY OF TEXAS AT TYLER i ABSTRACT The objective of the laboratory activity was to develop an RC (Resistor Capacitor) filter circuit to condition measured data through the data acquisition system (DAQ). In order to test the objective, signal conditioning was used. “Signal conditioning is the action of improving electrical signal by removing unwanted signals” [1]. Voltages from transducers or electrical output sensing devices can contain unwanted noise or frequencies that can cause errors in the data as it is converted to an electrical signal by the DAQ system. The data acquired through the DAQ system came from two signal generators, a BK Precision 4017A [2] and Proto-­‐Board PB-­‐503 [3] In the lab activities, the signal generators were used individually and as a combination. A first-­‐order Butterworth active filter was created to filter out those unwanted frequencies from the signal generators. A filter allows only specific frequencies to pass. From the results, the Butterworth filter performed as expected, eliminating unwanted noise frequencies above 100 Hz. Which in turn showed that the proto board was not functioning properly. ii TABLE OF CONTENTS Introduction.…………………………………………………………………………… 1 Methodology. …………………………………………………………………………. 2 Equipment and Material List……………………………………………………… 2 Equipment Apparatus…………………………………………………..…………. 4 Experimental Procedures……………...………………………………………….. 6 Results. …………………………………………………………………………………. 9 Discussions. ……………………………………………………………………………. 12 Conclusion ……………………………………………………………………………… 14 References. ………………………………………………………………………………. 15 Appendix A ...…………………………………….……………………………………… 16 Appendix B ...……………………………………………………………………………. 17 iii INTRODUCTION Electrical filters are categorized as highpass, lowpass, bandpass, and bandstop. Each of these types of filters can block different magnitude of frequencies. For example, an ideal lowpass filter will block higher frequencies and allow low frequencies to pass. Operational Amplifiers (Op-­‐Amp) help engineers to construction electrical filters. Constructing a lowpass filter, to work under ideal conditions in the real world situation is basically impossible. However, you can simulate ideal conditions with a flat passband signal filter. A Butterworth filter can maximize flat magnitude response in the passband simulating ideal conditions. Butterworth filters are relatively simple to design using an inverting op-­‐amp wired in a RC circuit. This particular filter can be made more complex by increasing the number of resistors and capacitors for a given application. In this lab a basic First-­‐order Butterworth filter will serve this purpose. In order for the Butterworth filter to be effective it should be placed between the proto board and the DAQ; that way it filters the higher frequencies out before it gets to the signal conditioning system. Finally the collected data will be displayed in LabVIEW. Once the data is displayed in LabVIEW, analysis on the output sine wave will confirm if the butterworth filter is fully functional. 1 METHODOLOGY Equipment and material list The signal conditioning experiment contains a Proto-­‐Board PB-­‐503 that was used to generate functions and the negative signal serves as the ground for the Proto-­‐Board. DAQ System, was another equipment used to set sine wave signal with a frequency of 100 Hz and an amplitude of ±3 Volts. In addition, a BK Precision 4017A was used as a signal and function generator. The specifications of the materials are listed in Table 1 [4]. Table 1: Product Specifications Equipment Proto –Board PB-­‐503 Output Frequency Characteristics Characteristics Impedance of 600 Ω 0.1 Hz to 100 kHz Sine, Square, Triangle DAQ System BK Precision 4017A ±2, Range ± 10, Non-­‐periodic and Periodic 0.2 Ω waveform 50Ω ± 10% impedance, Sine, Square, Triangle, Amplitude Variable, 20 dB ±Pulse, ±Ramp, 0.1 – range, Attenuation -­‐20 dB 10MHz, ±5% of coarse ± 1 dB setting, 5 digits 2 Figure 1. Proto -­‐ Board PB -­‐ 503 Figure 2. BK Precision 4017A & 4040A 3 Figure 3. NI USB 6211 DAQ System [5] Experimental Apparatus Figure 4 shows the experimental setup for Activity 1. The DAQ is connected to the proto board using positive and negative leads. Figure 5 shows experimental setup for Activity 2. The DAQ is connected to the BK Precision signal generator. Figure 4. DAQ is connected to Proto Board PB-­‐503 4 Figure 5. DAQ is connected to BK Precision 4017A Figure 6 shows the experimental setup for Activity 3. The DAQ is connected to both the Proto Board PB-­‐503 and BK Precision 4017A. Figure 7 shows experimental setup for Activity 4. The DAQ is connected to the Butterworth filter. Figure 6. DAQ is connected to PB-­‐503 and BK Precision 4017A 5 Figure 7. DAQ is connected to Butterworth filter Experimental Procedures This experiment involved four separate activities, in which all show different ways of signal filtering and also used different frequency ranges. In LabVIEW the settings for the DAQ were set at RSE Terminal Configuration, -­‐10 to 10 Volts signal input range, and a continuous sample acquisition mode of 100 samples. Activity 1. The proto board was connected to the DAQ and was used to create a sine wave signal. The positive and negative ports from the DAQ were connected onto the Proto Board. The frequency slider was set to the max position on the board and the amplitude was set at about halfway. The sampling rate was set at 2kHz. Then LabVIEW was used to collect the data and graph it. Screen shots were taken of the graphs to further evaluate the data. 6 Activity 2. The proto board was replaced with the BK Precision signal generator. In order to have a floating signal the signal generator was connected to the power outlet using a two-­‐prong plug adapter. The frequency was set to 1000 Hz and the amplitude at ±1V. The sampling rate was set at 20kHz. The data was collected and graphed in LabVIEW. Screen shots were taken of the graphs for further evaluation. Activity 3. In this activity a combined signal was required. Both the proto board and the BK Precision signal generator were connected to the DAQ. The proto board gave an unwanted 1000 Hz signal while the signal generator gave a 100 Hz signal that was wanted. In order for this to work, the positive of the 100 Hz signal was connected with the negative of the 1000 Hz signal. Therefore the negative of the 100 Hz signal is now the negative of the combined signal and the positive of the 1000 Hz is now the positive of the combined signal. LabVIEW collected the data and graphed it. Screen shots were taken of the graphs for further evaluation. Activity 4. This activity required the construction of a Butterworth active filter using a 741 Op-­‐Amp, 2-­‐6.3 kΩ resistors, 2-­‐1 kΩ and capacitors. This filter was added to Activity 3 setup. All LabVIEW settings from Activity 3 remained the same. Figure 7 Figure 8. Butterworth active filter [6] 8 RESULTS Figures 9, 10, 11 and 12 show the Labview results of activities 1, 2, 3, and 4 respectively. According to figure 9 below, the Labview output of the sine wave signal was displayed with a skewed representation of the output signals. Figures 10 and 12 shows an expected display of the output waveform. All experiments were carried out under standard conditions and temperature. Figure 9. Activity 1 Labview output display 9 Figure 10. Activity 2 Labview output display Figure 11. Activity 3 Labview output display 10 Figure 12. Activity 4 Labview output display 11 DISCUSSIONS The first activity of this experiment surfaced a concern due to inaccurate waveform generation from the proto board. The initial setup of activity 1 using the DAQ system and the proto board fails to give the required waveform. The waveform display was similar to the one in Fig. 9. Different frequencies were tried in order to troubleshoot the waveform because it was a bit skewed from expectation. All efforts to find a meaningful result for activity 1 were unsuccessful. Consequently the team suspected defective equipment in the connection. Therefore all the equipment was replaced except for the proto board. Even then no conclusion could be made at the time due to insufficient evidence identifying the proto board as the culprit. Activity 2 was a similar setup as activity 1, except the proto board was replaced by the BK precision. This activity required signal generation at a different frequency from activity 1 and the waveform generated by this activity was similar to what was expected. (See Fig 10). Results of activity 2 furthered the idea that the proto board might be generating unwanted signals and since no filtering was connected in activity 1, the waveform has no means of discarding unwanted signals or distortion in the waveform. Activity 3 requires both the proto board and BK precision equipment to be connected together, and the waveforms generated were also similar to the activity 1. Results confirmed the initial suspicion that the proto board was defective and could not be relied on in getting expected results in this experiment. Activity 4 requires the construction of a Butterworth active filter on a breadboard circuit in order to have a signal filtering system and so as to see the effect of a filter within 12 the line. (See Appendix A for Butterworth circuit diagram). The Butterworth was connected to the proto board and it filters the unwanted signals coming from the proto board and the results were close to expectation. The result of the experiment was shown in Figure 12. 13 CONCLUSION Upon conclusion of the experiment it was determined that the Proto Board was not working correctly even after checking that the setup was correct. The results of Activity 1 were not as expected. It appeared that there was still a lot of noise frequency getting through. Activities 2 and 3 were better but not exact. Activity 4 required assembly of a First-­‐Order Butterworth Active Filter. After applying the filter, the sine wave outcome was more accurate. Overall, the experimental data did not come out exactly as theory suggests but after manually doing the lowpass filter it was proven that the proto board was faulty. Therefore the outcomes in Activities 1 through 3 were not as accurate as Activity 4. 14 REFERENCES [1] Wheeler, A.J, Ganji, A.R. (2009) Introduction to Engineering Experimentation. Third Edition. [2] (2012). Web. Nov. 1 2013 [3] -­‐trainers/analog-­‐a-­‐digital-­‐circuit-­‐design-­‐ workstation/item/97-­‐pb-­‐503.html (2010). Web. Nov. 1 2013 [4] (2009). Web. Nov. 1 2013 [5] -­‐6211_Setup.html Web. Nov. 1 2013 [6] Dr. Rafe Biswas. (2013). Signal Conditioning. Lab Handout MENG 3210, The University of Texas, Tyler. 15 APPENDIX A-­‐ DIAGRAMS AND GRAPHS Circuit Diagram 1. – First-­‐order Butterworth Active Filter 16 APPENDIX B -­‐ PHOTOS Photo 1. Team DAQ 17 ...
View Full Document

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern