The alien stasis chambers have recessed, backlit touch controls. The shape of each looks like a letterform. (Perhaps in Proto-Indo-European language that David was studying at the start of the film?) David is able to run his fingers along and tap these character shapes in particular sequences to awaken the alien sleeping within.
The writing/controls take up quite a bit of room, on both the left and right sides of the chamber near the occupant’s head. It might seem a strange decision to have controls placed this way, since a single user might have to walk around the chamber to perform tasks. But a comparison of the left and right side shows that the controls are identical, and so are actually purposefully redundant. This way it doesn’t matter which side of the chamber a caretaker was on, he could still operate the controls. Two caretakers might have challenges “walking over” each other’s commands, especially with the missing feedback (see below).
Having the writing/controls spread over such a large area does seem error prone. In fact in the image above, you can see that David’s left hand is resting with two fingers “accidentally” in the controls. (His other hand was doing the button pressing.) Of course this could be written off as “the technology is not made for us, it’s made for an alien race,” but the movie insists these aliens and humans share matching DNA, so apart from being larger in stature, they’re not all that different.
Two things seem missing in the interface. The first is simple feedback. When David touches the buttons, they do not provide any signal that his touch has been received. If he didn’t apply enough pressure to register his touch, he wouldn’t have any feedback to know that until an error occurred. The touch walls had this feedback, so it seems oddly missing here.
The second thing missing is some status indicator for the occupant. Unless that information is available on wearable displays, having it hidden forces a caretaker to go elsewhere for the information or rely solely on observation, which seems far beneath the technological capabilities seen so far in the complex. See the Monitoring section in Chapter 12 of Make it So for other examples of medical monitoring.