Kerbal Space Program is really more of a space exploration simulator than a video game. Players are challenged to develop their own space program for the Kerbal aliens, design rockets and space craft, and use those craft to navigate space by utilizing very realistic physics. More often than not, things end in disaster. Because the physics simulations are realistic, you have to pilot the space craft like an actual astronaut would. That require precise control, which is why redditor MelkorsGreatestHits converted a vintage TI-99/4A computer into a controller for the game.
Normally we wouldn’t condone the use of a vintage computer like the Texas Instruments TI-99/4A in a project like this, but MelkorsGreatestHits was left with the enclosure and keyboard after using the internal electronic parts to resurrect other computers. We’re glad that was the case, though, because the aesthetics of the TI-99/4A perfectly suit the Space Race era feeling that Kerbal Space Program elicits. The TI-99/4A enclosure was heavily modified to add many additional gaming controls, including a joystick, throttle controller, various toggle switches and buttons, indicator lights, alarms, and even an industrial emergency stop button. The original keyboard also remains completely functional.
Both the Rotational Hand Controller (RHC) joystick and the throttle controller are modelled after those used in the actual Apollo Command Module, and were 3D-printed. A XIN Mo 2 Player MAME USB board is used to connect those and the other various switches to the computer running the game. The TI-99/4A’s keyboard is connected separately through a USB conversion kit that was developed specifically for that computer. The emergency stop button is housed in a separate enclosure that was originally a speech synthesis module. Vintage-style labels accompany each control, and MelkorsGreatestHits even went as far as creating a new “Kexas Instruments” label, complete with logo. The result looks fantastic, and we can’t imagine a more immersive way to play Kerbal Space Program.