mesuring the real speed

[aginor]

as you see in the image i am ploting the results of the sine derivetive in the "waveform chart" the chart shows the speed of the sine.

know i am putting the amplitute of the sine in one "siftregister". If i subtract the two "siftregisters" i am finding the dx

the same procedure for the time too. with this i am finding the real dt. this is an example, my real VI is too big and some times i am out of time......

then i divide this 2 and i am making the dx/dt, the speed but not m/s!! it is m/100ms!!!. this is diferrent from the other derivatite.

for my aplication i need the speed. The average speed in m/s that "happens" between to circles!!!! how i can mesure it??

thanks from the begining.

i make a VI with inteligents!! i will explain later........

[Minh Pham]

QUOTE (aginor @ Oct 17 2008, 08:24 AM)

as you see in the image i am ploting the results of the sine derivetive in the "waveform chart" the chart shows the speed of the sine.

know i am putting the amplitute of the sine in one "siftregister". If i subtract the two "siftregisters" i am finding the dx

the same procedure for the time too. with this i am finding the real dt. this is an example, my real VI is too big and some times i am out of time......

then i divide this 2 and i am making the dx/dt, the speed but not m/s!! it is m/100ms!!!. this is diferrent from the other derivatite.

for my aplication i need the speed. The average speed in m/s that "happens" between to circles!!!! how i can mesure it??

You have a timming Vi set to 100ms so you have m/100ms, if you set that to 1000ms then you have m/s.

The execution control timming of 100ms might not give you exactly 100ms everytime, this function depends on

alot of other factor from OS and other programs that run in the background. Hope you take this into account.

Have a look at the Mathematics>>Integration and Diff>>Derivative X(t) vi as well.

[scott123]

You should think about initializing that shift register.

[Minh Pham]

QUOTE (scott123 @ Oct 17 2008, 12:43 PM)

You should think about initializing that shift register.

0 is assigned to all shift regs, isnt it?

[aginor]

QUOTE (Minh Pham @ Oct 17 2008, 05:21 AM)

0 is assigned to all shift regs, isnt it?

correct

QUOTE

not give you exactly 100ms everytime

and this is true. how i can convert is time to be m/s i am measuring the time of the circle by the tick count. and then what i have to do??

[crelf]

QUOTE (scott123 @ Oct 16 2008, 09:43 PM)

You should think about initializing that shift register.

Which one? They look okay to me...