SE may be the reason I'm having a similar issue with collision like others have said with vehicles.

Trying to run in a straight line with the drone out and sometimes I would bump into the drone. Which just moves my character ever slightly left or right. So running in a straight line is fine without the drone but with it out it'll move stutter a bit when running the same. I do have some legs and with runspeed so I can run pretty fast. It's actually kinda annoying. I have to pick up the drone when traveling around my base sometimes because of the left and right shifting the character does with it.

I've used the original construction drones in my SE playthru fine. Recently upgraded to 1.1.x and notice this was supposed to be the new replacement. I actually prefer the original construction drones atm. Even with them getting stuck occasionally. At least with that, the times they do get stuck is much less often then me running around have constantly having my character being bumped around.

Any way we can maybe adjust how close the drone flies by the player? When I'm in the jetpack the drone seems to hang farther back so it never gets a chance to bump into the character. Which, while not the reason at least it doesn't bump the player around while moving.

Can you provide a save game?

Yes I can. I can even do one better.

I tried it on V53000's saved game ( https://imgur.com/a/LdR58ep ).
He's using just about the bare minimal mods needed for Space Exploration. I synced his mods and just added your Companion Drones. North of where his final save is contains his space mall which has everything needed to make the companion including the fish. It exhibits the same behavior as my game when running around. It's more noticeable running north/south while avoid any belts or obstacles. You can walk over the space pipes, but even avoiding them you can see your character shift around on plain ground.

Here's my test save of that same V53000's file:
https://drive.google.com/file/d/1yt4cslhu8XfVP1bLVkjCLytKzISvYNfv/view?usp=sharing

I have my personal save as well if you rather have that. But there's a lot more mods and much heftier file size and I wanted to be sure it wasn't caused by one of them.

Hope this helps.

Thanks, it was related to Alien biomes and Space exploration, should be fixed now

I actually grabbed it right after you put the newest version up. I just wasn't in space to check but now that I'm not longer planetside it does look like it no longer jitters around. Thanks for the quick fix.