Retro Engines

[Shockeray]

From watching the May Dev Update I realized that I disagreed with another member of Soul Nebula on what the Retro Engines were. Does it appear from the video that they are actually standard rocket engines that are going to have to be positioned correctly to fire in opposition to earlier acceleration, or are they more like a magic momentum-negating box?

[Haunty]

I'm guessing they're magic and effectively the same thing as inertia dampeners in other games.

[Lord_Void]

I agree, from the looks of it they are more like magic inertial dampeners

[devu]

Not sure why you call it magic, because if I understood correctly by the look of it, it is trying to mimic Reaction Control System, RCS thrust engines. 
It helps to keep/correct desired trajectory and momentum of the vessel. Why JC would call it Retro on the video? No idea... maybe it was misunderstood for :

 

retrofit

Quote

add (a component or accessory) to something that did not have it when manufactured.

 

[Shockeray]

5 minutes ago, _devu_ said:

Not sure why you call it magic, because if I understood correctly by the look of it, it is trying to mimic Reaction Control System, RCS thrust engines. 
It helps to keep/correct desired trajectory and momentum of the vessel. Why JC would call it Retro on the video? No idea... maybe it was misunderstood for :

 

retrofit

 

I am loosely familiar with RCS (mostly from KSP) and immediately recognized the model, but I was curious if they were going to be using actual thrust vectors to inertia-dampen or were just going to magically remove all momentum besides forward.

[Lethys]

yeah, I doubt they work like in KSP....

 

in the video he says: "(...) generate artificial friction which helps to align the ship movement with the ship from direction"

So to me this sounds like a magic box and not actual thrusters. Which is fine, by all means

[Velenka]

Makes me wonder why it was described as a magic box when I can see thruster nozzles all over it. Maybe the in-universe explanation is that it is an RCS module, while in reality it's a magic box. The "adjustors" from the Spaceship Building Devdiary also seem to be similar in function, although he says that they produce thrust, and are responsible for turning the ship (around 7:50).

[ATMLVE]

I was under the impression they were like turning on inertial dampers in Space Engineers. While the game is in space, and speed is technically relative, and everything should be moving, in reality the world itself is a reference frame and the ship speed is relative to that.

 

So what the "retro" engines from the devdiary do (I think) is stop the ship in space so that the speed is 0. This would help with things in open space like bases, docking, mining, etc.

 

JC said that it creates friction in space. Friction is just a force that opposes motion, it only pushes back when something is pushing on it. Think of a big sheet of carpet. Inertia dampers that bring ship speed to 0 really are kinda exerting friction in space.

[Velenka]

Well, the distinction is only really technical. JC probably meant it emulates friction like you would find in a fluid environment, rather than simply the reduction of lateral velocity, even though the former implies the latter.

 

Also a true RCS would be able to cause acceleration and rotation, and if "Retro engines" really are just artificial friction generators, they wouldn't be able to do that. I would probably suggest that the "Retro" and adjustor engines be combined and called RCS so that we can stop all this confusion. xD

[Inasyah]

I for my part don't believe that they are artificial friction generators.

DU is trying to be more on the realistic side of things (the Placement of the Engine has real effect on the Direction of its Thrust - Physically correct).

Having something that artificially without any explanation generates friction like some have already mentioned as being a 'magic' device doesnt fit in for me.

I think they really are what you would classify as a RCS and naming them 'Retro Engines' was just done to make them be easier understood by most people.

[Velenka]

I would expect an RCS system to be unable to provide enough thrust to significantly alter translational velocity. A "Retro" engine should just be a normal engine pointed in the backwards direction. For a large and massive enough ship, even RCS modules should be incapable of working, requiring normal engines to be capable of applying any change in translational or angular momentum.

[devu]

Once again, I'm pretty sure he meant 'we retrofit' new type of engines not we made new 'Retro' engines  

[Shockeray]

9 minutes ago, _devu_ said:

Once again, I'm pretty sure he meant 'we retrofit' new type of engines not we made new 'Retro' engines  

Since a retrorocket is a real thing, I just assumed that retro engine was another way of saying it.

"And we have developed retro engines that can be used to generate artificial friction which helps to align ship movement with the ship front direction." -JC