There is nothing wrong with having a floating static menu that follows the page as it scrolls.
In fact, this very site (and all SE sites) have pretty much the same concept with how the menu works (to the left). Sure, it is a little dynamic in some parts, but for the most part it follows the user as the view the contents of the page.
The benefit is that regardless of how far the user scrolls, they can still easily access the features they they want to get to without having to scroll back to the top. This is a good thing for the user experience.
However, there are a couple of considerations to be aware of that could result in a bad design if not careful:
- Make sure the floating menu isn't able to overlap any of the page content. It would be annoying if a user is unable to read something because the menu is obscuring it.
- Make sure the menu includes features that the user will likely want to use. It is no good having a fixed menu if the user isn't interested in any of the items. Don't have one just for the sake of it.