testing ground

[king of nowhere]

as i try to make something more complex than a rocket, i realize more and more than i need to test everything. my tried-and-true method of save-scumming does not work anymore if i sent a month-long mission and i find out upon arrival that something does not work properly. not when in that month i did dozens of other missions that i would lose completely upon reloading.

however, i don't have any good way to test pieces. i try the rovers on kerbal, but on the lower gravity of the moons they behave differently. i built a robotic crane to work on mun, and of course it won't work in kerbal's gravity, but will it work in mun's gravity? did i put enough heat radiators for an eve mission? how do i know without getting to eve in the first place? i am afraid my robotic arm is placed in an awkward position and will not be able to extend, can i try it without driving through half of kerbal to find a baobab for the test?

so, I'd like to know if there was some easier way to test a piece than driving it all the way to its intended destination. some sandbox mode that would give me the option "try this rover on mun with a crater nearby" or "have those two ships in space to see how well they couple together". is it possible?

[AHHans]

You can use the cheat menu (on Linux: <R-Shift> - <F12>, on Windows <R-Alt> - <F12>) to "cheat" a craft into orbit around any celestial body or onto the surface of a CB.

I personally don't call that "save-scumming" but "in-game computer simulation".

[jimmymcgoochie]

There is a sandbox mode- it's called sandbox mode! If you dig into your save game (KSP/saves/your save) there's a folder called Ships which contains all the designs you have made and saved in the VAB, SPH and subassemblies; copy the files for the craft(s) you want to test out and paste them in the same folders in a sandbox save, then you can try them out as much as you like.

[Draalo]

The cheat-menu allows you to set the gravity. I use it often when i build rover cranes which should assemble a base from non-rover modules.

If you want to use sandbox mode for testing i recommend KSP Craft Organizer - this mod allows you to load vessels in VAB/SPH from other save games.

[Cavscout74]

Another option if you have Making History is to make a mission, spawn the craft you want to test wherever you want to test it and run the mission.  It's more work, but sometimes worth it.  Like if you want to see if your Eve ascent vehicle will actually make orbit, but aren't ready to build the full setup to launch from Kerbin, transfer & land on Eve.

Yet another option is the mod Hyperedit - it does essentially the same as the cheat menu movements, but can also land your craft on a body to test it without having to go through landing it yourself.

Typically, I'll test new designs in sandbox with Hyperedit, then when I'm satisfied, move the craft file back to my career save.

[Grogs]

It really makes you appreciate real rocket scientists, doesn't it? They have to design something and not find out until years later if their lander actually works.

Luckily, we don't have to. I use the ALT-F12 cheat to test things all the time though. I can't imagine doing an Eve mission without it. You can set things on the surface with the 'Set Position' although the trick is finding the right spot since you have to enter a lat/long. For testing landings or maneuvers you can use 'Set Orbit' in the cheats section.

[king of nowhere]

ok, the cheat mode is very useful to test rovers on various planets.

just a question, if i touch the other setting, do i risk to mess things up permanently?

[AHHans]

9 hours ago, king of nowhere said:

just a question, if i touch the other setting, do i risk to mess things up permanently?

Not permanently permanently. The settings you do in the cheat menu will last while the play-session is running, so if you e.g. test a craft, set "infinite fuel", revert to the VAB, go out of the VAB, and go to one of your existing craft, then it will still be active. Also when you (quick-)load a savefile in your current session then the cheats will not reset. But if you exit KSP and then start it again then all the cheats will be reset.

P.S. But the "Set Orbit" and "Set Position" cheats are obviously fairly safe to use.

Edited June 12, 2020 by AHHans

[Linkageless]

I have a separate sandbox to develop craft in, often removing most of the fuel and cheating them into orbit round the target body for a simulated proof of concept mission.  The iterations I go through in this are as fun as doing the final mission.

Once happy with the design, I copy my final .craft file to my career Ships folder so I can keep the career cheat free.

There's some missions I'm happy to 'wing it' with, so do the build in career and just go for it. The occasional missing ladder is all part of the fun, isn't it?

 

 

And to answer the specific case of rovers, there's a cheat to surface position in there since 1.9 I think, which is quite a time-saver once you have figured out the important settings.