Capstone Design 2001

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   Remote Laboratory Station 
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Screenshot for April 19, 2001 (Latest Update)

This is how a workbench would look like, minus the boards.

WorkBench Sample
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Welcome
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Team D is creating a Remote Laboratory Station that virtually simulates Electrical Engineering laboratory equipment for the purpose of distance education. Our product will directly increase enrollment in Northern Arizona University engineering courses by allowing distance-learning students to take engineering lab courses. This increase in enrollment will thereby increase university income and university prestige.

Update
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As of now our project is progressing to the point of testing combined components.  

Our USB interface controller is being shipped, and should arrive in a day or two. Our FIFO's will be ordered once we determine the speed of the USB controller as it interfaces with LabVIEW.  As long as our USB controller works as advertised our FIFO depths and speeds should stay the same as shown on the block diagram. We have downloaded the DLL (driver files) and LabVIEW drivers for this USB controller and have set up a folder on our computer at our workstation that contains all LabVIEW VI's to date.  

Some of the test VI's that were created over the Christmas break were a "test_Oscilloscope" VI that will be used for initial USB interfacing, "Data_Capture" VI that is used to experiment with capture speeds, and a "Boolean_Reader/Grapher" VI that shows how to create and graph a Boolean array.  

We have drawn up a preliminary block diagram that contains all components and the overall flow of the circuits (these block diagrams are attached). 

We have also determined speeds and resolution sizes for our A to D's and D to A's, as well as our low pass filter for wave capture.  We will be ordering these parts within the week; once again, after the USB interface is tested and its peak speed determined.  

Calculated Results:

 After preliminary testing of LabVIEW it was determined that LabVIEW is extremely slow when it comes to creating an ordered array of some large size. Because of this we are going to be using three clocks to run the CLKIN and CLKOUT of the two FIFO's. There are three main reasons for this:

   1.  We can keep the FIFO depth down and therefore it is cheaper and we can clock in all data much quicker.

   2.   We can attain a better range of frequency (200khz, 20hz)

   3.    We can maintain a better wave resolution over the most popular spectrum of frequencies.

The actual clock speed will be chosen by the user using a three-pole VI switch (High (200khz to 500hz), Med (500hz to 100hz), and Low (100hz to 20hz)). These frequencies were determined to give the High clock 2.5-1000 samples/period, and the Med and Low clocks limits of 200-1000 samples/period. The Med and Low upper limits were set at 200 to allow for greater resolution at these most common frequency ranges.     

Problems:

  As stated before, we will not have any hard specifications on speed of wave acquisition, or production until we test all components together, especially our USB controller.  This is due to the large number of unknown variables when dealing with this relatively new USB technology.  As it stands now our best guess of frequency range is 200khz to 20hz.

A major problem we have had in the last month is getting our USB controller delivered. It seams our order was misplaced the first time and therefore had to be reordered.  Because of this we have been on hold for at least the last three weeks. 

A potential problem is that we may have trouble interfacing two of these ActiveWire USB Controllers at the same time with LabVIEW. Kevin Sova has talked to ActiveWire's technical help, and they don't think it should be a problem. The team will determine this by trial and error. 

 

Note:
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