How do I count events falling into three categories?

Question

Hello everyone,
   My name is Sean Cummings. I am very new to Labview and this is my first post on the forum. I work for a testing facility dealing with automotive components. I run test cells and build parts. I recently commissioned a new test cell at our location which came from another one of our facilities. The test cell impacts axles. The Labview program we use to run the cell was created by one of our few programmers. He is extremely busy and works in another facility so I have taken it upon myself to learn more about Labview and try on my own to make improvements to the software. I plan to attend some of the Core Labview classes if I find that I enjoy working with the software (so far i do).
   Currently the program is mostly manually controlled. Data paths and controls such as speed are commanded by the operator. There is a 4 second automated cycle in which the Labview VI commands clutches to initate the impact and aquires data from 3 load cells and a speed sensor. Once this cycle is complete the operator must click a button to open a call by reference subvi. The subvi analyzes the impact data and displays a graph as well as several calculated data points. The operator is then required to open an excel spreadsheet and manually enter the data. I created the spreadsheet with conditional formatting to show the operator whether the impact event was within the acceptable range and to track impacts over target, in target range, and under target. Currently each part runs 400 impact cycles and the operator must transfer 6 data points for each impact. In the next couple weeks we will be testing parts going 1640 impact cycles. We need a better solution to make the process more efficient.
   My original thought was to have the subvi populate the excel spreadsheet automatically. After several days of trial and error I was able to speak to a programmer from another facility who explained to me that excel was not not a text based software and my methods would not work without the Labview excel toolkit.
   I then talked to the engineers within my company and they agreed with me that the excel spreadsheet was not necessary if Labview could track the impact events internally. I then set to work trying to create counters and indicators to track the impact events. For this to work I only need to look at one number. This number is the Total Output Torque from the impact event. I created 3 boolean indicators on the main VI. One for impacts over target, one in range, and one under target. I also created 3 corrosponding indicators to show counts for each. I also need an indicator showing total impact events, and an indicator showing valid impact events (the sum of in range and over target).  I use a control for the target . The range is + or - 5% from target. I have done my best to research and try to do this myself, but I can't quite get it right. I am using while loops to count. I encounter problems with multiple counts for the same event. I would also like to trigger the counters at the same time and not have separate stop commands for each.
   For this to be effective I will probably have to make these functions a subvi. I would need them to initiate when the call by reference "analysis" subvi is called and stop when it stops so maybe they can just be part of that subvi.  I need the indicators and control for target to be on the main UI. I also need a button to reset the counts when impact direction and target is changed.
   I apologize for any misuse of terminology. I also apoligize if my program is a mess. This is all very new to me and I'm trying to learn as much as possible. Thanks you all in advance for your help.
   -Sean-
Solved!
Go to Solution.
Attachments:
Impact Counter_2.vi ‏16 KB

Answer 1

Wow! Thank you guys for the quick response and pointing me in the right direction!
Altenbach, your example does exactly what I need! 
Moving forward I should be able to reference the actual total torque number from the call by reference subvi and have the event structure initiate based on the change of that number correct?
I tried something like this already and for some reason when I add a terminal to the terminal pane on the subvi it does not show up on the main vi. I can only imagine this is because the sub vi is "call by reference". The subvi already outputs an indicator to the front panel of the main vi called "total torque". This is inside a case structure so I don't know how to reference it for the subvi which you created.
Again, I just want to say I am very thankful I am for the help. I am not here looking for free programming help. I am here asking questions because I truly want to learn. I know I will have to spend a lot more time reading tutorials and practicing basics. This program was just given to me last minute and I'm doing my best. Usually I am very resourceful and can find solutions on my own. This one was just over my head. Thank you.
  -Sean-
Attachments:
Impact Tester Main_03.vi ‏245 KB
ITS_Data Graphs.vi ‏567 KB