the simscape of mass-spring-damping system can't get the ideal result

in the simscape,the mass-spring-damping system,

i set the signal builder build the force as this,

and in the motion sensor,the initial position is 5,so the

The displacement and velocity should be attenuated, but why would you get such a result?

Mass spring damping is international unit 1

and the figure 3 is position and the figure 4 is the velocity

Answer 1

[Stephan]

Hi,

did you notice that you can accept and/or vote for useful answers? You have a asked a bunch of questions ang got some answers. Accept them, if they helped you. It is the contributers reward here.

Regarding your question:

you should set an initial value for the spring also. The initial state of the system will have no energy in it, so nothing happens. If you set an initial value of 5 to the spring also, things change (scroll to the right):

Best regards

Stephan

[dcydhb dcydhb]

Is the deformation a positive number, which means the spring is elongated?

[dcydhb dcydhb]

If the spring is in a natural elongation state at the beginning, the elongation is 0, that is, it is not compressed, and then the object is in the initial test position of 5. after letting go, the object should also drop a part. how to set this?

[Stephan]

https://de.mathworks.com/help/physmod/simscape/ref/translationalspring.html#bqfvzn8-3

see xinit

Do you mean it should be compressed by gravity?

If so check:

https://de.mathworks.com/help/releases/R2014a/physmod/sm/ref/mechanismconfiguration.html

[dcydhb dcydhb]

i have accepted and thanks a lot!

but there are several questions,

1,i can't see the document ，in your

If so check:

2, In simscape, when the spring is elongated, the deformation becomes positive?

3，How to define whether the positive direction of displacement is up or down？

[dcydhb dcydhb]

and also i change the direction of r and c port of the spring ,the result changed,and what is the difference between r and c port?

[dcydhb dcydhb]

and also why when i delete the mtr1,it can't run out the result?

[madhan ravi]

It's only 5.36 am in Europe you need to wait , people have to sleep.

[Stephan]

The block positive direction is from port R to port C. This means that the force is positive if it acts in the direction from R to C.

[dcydhb dcydhb]

thanks a lot,why your model is different from mine,for example,the color is green and it seems that you have You're missing some components.

my version is r2014a,is it because the version and higher version has Fewer components？

[Stephan]

It is opened in R2019a, but i did not do any changes. Just because the version.