Help with completion of Accelerometer and Heel force VI please

[Justin.]

Hey Mark,

I've attached an example that demonstrates what I think you want to see.
I create an array that is 740 points in length, the same as your original array, and increment in steps of 0.01. This gives 740 points, but with a maximum value of 7.4
I then use that as my x-axis. I use your original array as my y-axis. and feed this into an x-y graph (after bundling it).

This shows the graph I think you want to see, although I've just manipulated arrays and this has no relevance to real time.

Let me know what you think.

[mbrolly2]

Hi Justin,

Thanks for the continued help. The LabVIEW I have installed is the 2012 version so I will need an hour or two before I can see your example. I will respond ASAP. Thank you in advance.

Kind Regards,

Mark

[Justin.]

Hey Mark,

Attached is a 2012 version and a screenshot.

[mbrolly2]

Hey Justin,

I'm not sure what the etiquette is with Kudos but I gave you one because I found it helpful. How would I move the lines either side of the dip?, By changing the values in the block diagram?. 

Would you recommend using the same principle for the FSR VI?

Kind Regards,

Mark

[Justin.]

Hey Mark,

I believe the general consensus is that kudos is given to users as an appreciation of their post being useful or relevant. Most often kudos is given to the person that gives the best or most appropriate solution, but also sometimes to those who provide valuable information that isn't necessarily a solution. It's just a method of appreciation of someones help. In any case, I thank you very much for the kudos!

With regards to your VI. If I break down your y-array and your code, to visualise it.
You firstly create an array of 128 elements, all with the value 90. You then add a sine halfwave as the next 50 elements (or whichever value is in your "samples" control). Finally, you append another 512 elements, again all with the value of 90.

(As an aside I realise earlier I stated 512+128 = 740, I forgot to state you add the 100 samples you took to create the sine halfwave. Basic math failure on my part!)

So if you change the dimension size (either the 128 or the 512) you will start creating less and less, or more and more, elements with a value of 90, which will alter when the sine wave dip occurs in "time."

If you change the 128, to 64, your sine halfwave will now start at 0.64 seconds etc.

[mbrolly2]

Hi Justin,

I can't thank you enough for your help and helping understand everything, thank you for your patience you're very helpful. I will change the 128 and 512 constants to controls so they can be altered. I don't think I can get the X-axis to go to 10 seconds can I?

Would you suggest I do the same method for displaying the FSR VI but maybe multiply the Sine wave by -1 and enter a higher value for samples to broaden the wave?

Kind Regards,

Mark.

[mbrolly2]

Hi Justin,

Just an update, I increased the array to 950 in steps of 0.01 and it seems to of solved my question about the x-axis. I'm moving on to improving the FSR VI as we speak.

Kind Regards,

Mark.

[mbrolly2]

Hi Justin,

Sorry to keep updating the thread but I have just altered the ACC VI to represent the FSR VI as well. I changed the Sine wave values and others to get a rough curve of what I would like the graph to look like. However, would it possible to create a flat line at the peak of the Sine wave and then the curve descends at the end of the line?

Would it be possible to do with a sine wave of -0.25 cycles and an array and add another sine wave of 0.25 cycles?. To whomever is interested please find attached the FSR VI.

Kind Regards,

Mark

[mbrolly2]

Hi,

Another update, this VI displays heel force. The idea of the LED is to detect when a level of force has been detected, I think that would be the best way to display a sit to stand detector wouldn't it?. Two problems I'm facing are:

-When I increase the amplitude or force the line increases in both directions, how would I be able to stop this? Should I multiply it and return the signal so it only goes in the positive direction on the Y-Axis?. 

-How would I get the FSR to level off at the peak amplitude before it begins to descend?

Attached is my progress so far with this VI.

Kind Regards,

Mark.

[mbrolly2]

Hi Justin (and whoever else is following the thread),

I have put everything together in one VI and I have a basic sit to stand detector for the Trunk TIlt and the Heel Force, I don't think I can include the EMG in this it doesn't seem to work, any suggestions?

Also, I'm still having trouble with the design of the Heel Force/FSR part so any help there would be greatly appreciated.

I will attach the updated VI in a while I am away from my computer at the moment.

Kind Regards,

Mark.