First impressions not looking good

They work almost perfectly if you avoid doing anything stupid with them. It's your own fault if you tried to put two full blocks next to each other on different subgrids.

Your completely wrong,.. Try building a small ship in space and then attach a rotor then a block and then a piston in a 90 degree angle in any direction. then a rotor again, a block and finally one more piston in any 90 degree direction. On the end place a welder. Every time you use the rotors the hole ship start to roll and every time you extend the pistons the hole ship starts to tilt. Now all this might make perfect sense to you, but to anybody with any idea of physics, know that that's not exactly how its supposed to work. The pistons never stop pushing forward after reaching maximum distants and the rotors never stop pushing on their set limits or their locks. making the only solution to stop the ship from moving or shaking to turn the rotors completely off and retract the pistons. Also if you slightly bend a piston or a rotor head with a small block on the end, it's not supposed to be capable of rolling a 4000 ton ship in space. In fact it wouldn't make anything start rolling. Now go see if you didn't miss something in those tutorials will ya. and go try helping somewhere else.

And the @#%&!list just goes on on,.. Now assuming that you did somehow get it stable after you lock everything and turn everything off it should wile moving forward, start pulling on that arm but only taking account to where its attached to the main body. But that's not what happening ether... Its making calculation from grid to grid and not doing it correctly. You would assume that with onboard computers and gyros that you would be able to move forwards with out constantly tilting in some direction but they where obviously designed by people that knew as mush about pistons and rotor as you do.

So from what I'm seeing, you're making stupidly complex subgrid contraptions without proper spacing, running a bunch of moving parts at once, smacking it into things, and expecting them not to explode. It's like watching my ten-year-old self throw dozens of random Minecraft mods together and getting frustrated when it doesn't work on a potato PC.

This game isn't a robot arm simulator. If it were, they'd have a couple dozen rules shaving off floating point inaccuracies and preventing most of these things from happening while halving your FPS. But SE was built out of a voxel simulator and is about ship design, so the dev priority list has "spend a year or two redesigning the game engine to handle pointless masses of subgrids" somewhere between "moving, spinning planets" and "5mm block size"

Wow could you possibly get more clueless... Was it to hard for you? You don't even understand how it works or that it doesn't even have any collision issues. You even think that it's to much to expect to be able to build a simple two jointed arm with a wrist in a game that has the word "Engineering" in it. Obsessively your not doing mush of that. Lol! But sins your so interested in what I'm doing I'm actually building a big spaceship that doesn't need any fuel to get around as it has free propulsion in all directions just by letting one grid push on the other with "perfectly" working pistons and rotors. It runs on imaginary spring power. ha,ha,ha! You really should go back to Mine craft kid as you obsessively not doing much here..

"it doesn't even have any collision issues... letting one grid push on the other"

So is there a collision or not? Because multiple interacting subgrids is exactly how you get collision issues like free propulsion, by taking advantage of floating point rounding errors in positions and forces.

I'm not saying that SE physics doesn't have problems. It's just that the devs intended to use pistons and rotors any more than occasionally, and didn't put in the massive amount of work and processing power required to fix the issues that occur when you try to break the game. Acting like a two-jointed arm is simple doesn't change that subgrids, especially compounded, are the most difficult-to-simulate interaction in the game. The only way to make that kind of mechanism work is by either drastically oversimplifying the simulation, or throwing a high-end gaming computer at it. Neither of which Keen was willing to do, because both have massive downsides.

Also, it might help your case if you drop the insults. I'd wager that most people using online forums take the time to re-read their comments before posting, so you aren't going to get anyone angry enough to retaliate. And the devs strongly prefer to respond to people who seem reasonable in their requests or suggestions.