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Dependencies: ADXL362 Lab7 mbed
Diff: report.txt
- Revision:
- 2:1dab962fe6f0
diff -r ed3c12662b08 -r 1dab962fe6f0 report.txt --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/report.txt Wed Feb 07 22:47:01 2018 +0000 @@ -0,0 +1,38 @@ + +RESULTS: +Our end results were fairly good in terms of expected output, given the difficulty +of the task. When looking at our results of 1V sine waves, We noted marked +decrease in output voltage of sine waves that had over 200Hz. We also noted +some decreases at all increasing frequencies from the initial 100Hz. This is +evidence that our low pass filter is functioning differently than an ideal low +pass filter. + +Difficulties: +We had huge difficutlies with creating a sinewave that had accurate amplitude +and frequency. We eventually achieved this simply by taking several data points +from inputs of 5 - 70 micro seconds in delay, with ouputs of frequency from +100Hz - 500Hz, in delay and using this data to create a function that would then +work in the reverse. That is to say that we used the data points with frequency +as an input and the wait time as an output to convert input frequencies to +wait times that the STM board would then use to output the correct frequencies. +This function was relatively accurate, and ended up being more accurate than the +relatively simple and "exact" mathmatically correct function that converts +frequency to delta time. + +Expected vs Actual Results: +Due to this somewhat "approximate" approach to creating the correct frequency, +we obviously had some differences in our actual results when compared to our +expected results. Our generated function was most accuate at low voltages and low +frequencies, often achieving less than 1% error in the 1V and 100Hz range. When +using higher frequencies, the function would usually output a frequency that was +roughly 2-4% higher than our desired frequency. The voltage output was a similar +story, with 1V being almost perfect, while 3V was usually off by around 3-5%. +Because of these differences, and the nature of imperfect capacitors and resistors, +our actual results when measuring our low pass filter were even further from +the ideal results. We did note marked decrease in the output strength of +frequencies over 200Hz, but not as sharp of decreases as expected. We also +meausured a decrease in strength of the signal even when frequency was still below +200Hz, which should only happen when very close to 200Hz. These differences +must be attributed to many factors, the primary ones being slightly incorrect +voltage and frequency outputs, imperfect wires, resistor, and capacitors, and +some limitations in the measuring equipment. \ No newline at end of file