@cloudff7ps1
1) Refer to case documentation regarding the meaning of case LED's.
Flashing, colors, etc. vary between manufacturers. Colors may be misleading - a weak "orange" may appear "yellow". etc. Could be completely useless for those who are colorblind.
Or simply buggy for one reason or another.
2) I would not expect that a "knock or shock" with a hand would cause damage. Such a shock would likely include a broken hand....
= = = =
After reading the above posts, I became curious and looked into code that can be used to park (if necessary) hard drive heads.
I came across linux's "hdparm" command which appears to provide a way to park the head. However, the heads may be immediately unparked thereafter by other events.... Will defer to the Linux Community in that regard.
There is a HDPARM version for Windows:
https://en.freedownloadmanager.org/Windows-PC/Hdparm-FREE.html
I also found:
https://superuser.com/questions/1504490/how-do-i-spin-down-an-hdd-with-the-command-line
Overall, barring specific operational requirements specifying HDD head parking on command, my suggestion is to just simply ensure that all HDD data is fully backed up at all times.
Then "but I do not know what the position of the mechanical arm and needle is at that moment." is rendered moot.
Likely unknowable to begin with (beyond some general sector and track coordinates, etc. and, should it happen to be known, of limited value if data is lost.
Refocus your attention and energy on being able to recover HDD data for when (not if) any given HDD will fail.
Be that failure a "knock with a hand", a fall from a table, or just some gremlin in a bad mood.