generating a half wave sinusoid using Simulink

I am pretty bad at using Simulink and have tried for days to obtain a half wave sinusoid of the following equation: I(t)=360sin(pi*t/0.4), 0<=t<=0.4 I(t)=0, 0.4<t<=1

I just used a Sine block of amplitude=360 and frequency of 7.85 rad/sec together with a pulse generator block and multiply them together.

Any suggestions? I want to get the one in blue but I only got the one in yellow. :(

Answer 1

[Rick Rosson]

Try feeding the output of the Sine Wave block to the input of a Saturation block. Set the lower limit to 0 and the upper limit to inf.

[Cheryl]

I had done that already but it doesn't work :( I've included a picture in my original post for a clearer picture

[Rick Rosson]

Please check the Max step size parameter in the Solver Pane. My guess is that it is set either to auto or to a value that is too large relative to the period of the sine wave. With the sine wave having a period of 0.8 seconds, I would recommend that you set the max step size to 0.02 or even 0.01 seconds so that you will have high enough time resolution to represent the sine wave as a smooth curve.