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How to insert an extra Negative Step Signal

How to insert an extra Negative Step Signal

How to insert an extra Negative Step Signal

(OP)
How to insert an extra Negative Step Signal in the Circuit Diagram to reduce the amplitude.

RE: How to insert an extra Negative Step Signal



To reduce amplitude, one normally uses an attenuator.

There may be specific circumstances where it can become slightly more complicated, but the approach you're proposing ("an extra Negative Step Signal") is very unusual.

 

RE: How to insert an extra Negative Step Signal

(OP)
I need the Step Signal for a certain time and then need to reduce it for a certain time and then once again so on... yes it is unusual. Is it possible to do something like this?
I tried using Pulse but then Pulse signal completely goes down to zero and its of no use to me. tried Step with Exponential Decrease, its not good as well... Is there a way?

RE: How to insert an extra Negative Step Signal

Use the original signal to trigger a uC that emits whatever waveform you've programmed it to emit.
 

RE: How to insert an extra Negative Step Signal

(OP)
uC is?

RE: How to insert an extra Negative Step Signal

(OP)
I think the best way to deal with my problem is to use 1 step signal...
But What I need to achieve is for 10 secs i need Amplitude as 5 and then drop it down to 3. How do i achieve this?

RE: How to insert an extra Negative Step Signal

uC = microcontroller.

en.wikipedia.org/wiki/Microcontroller

 

RE: How to insert an extra Negative Step Signal

(OP)
The program is Hopsan NG. If you google the name, the first link gives the download link.

RE: How to insert an extra Negative Step Signal

(OP)
I cant use M.C in this simulation Software...

RE: How to insert an extra Negative Step Signal

(OP)
lol, sure....
thanks i guess i ought to do that...  

RE: How to insert an extra Negative Step Signal

(OP)
Well ok. Since people here have the idea about the system. The desired result is to stop the piston before it reaches end position in the software. This allows to reduce the high pressure buildup in the system as the piston is completely closed. Or in simple words, stop the piston after .8m, as the stroke length is 1m

RE: How to insert an extra Negative Step Signal

(OP)
What I am trying to do is in figure below, but then it still doesnt work. Is there a way to just completely shut off the Step Signal, once my piston reaches 0.8m.  
Yes, Hopsan works like AMESIM....and downloaded by googling it, the first link is download for Hopsan.

RE: How to insert an extra Negative Step Signal

Your program has a sum block.  Put a sum block after your original step and make another step that has the timing you want only negative in polarity and wire it to the sum block.

Or put a multiply block in with your step as one input and another source that varies from 0-1 with 1 being full on.

To attenuate reduce from 1 to say 0.8.

 

RE: How to insert an extra Negative Step Signal

(OP)
Ok. I think I have managed to put the 2 Step sources correctly. But still the Piston opens completely. The reason is the directional valve opens completely. How to make it open just half way and it stays there....I have posted here since its a control problem. I see it as the Step Signal is giving some signal at all time, so either the directional valve is open completely or closed. Is there a way to stop it at the middle. or say at .008 m

RE: How to insert an extra Negative Step Signal

(OP)
I cant stabilize the directional valve to be open at a certain position and similarly I cant make the piston to be open at a particular position! I dont know what to do. Help any one?

RE: How to insert an extra Negative Step Signal

Does this model allow you to set the valve at 0.8m at all? For the time being, forget about having it land there in a dynamic manner. Start by confirming that valve model by itself can be set to your desired position, independent of all the other dynamic considerations.

Next: Once you confirm the basics... I have my doubts that the modeling environment was intended to be applied at the component level; including the precise dynamic properties of a particular part number of real world valve.
 

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