Humans can't use alien tech (6)
- Arknights Others: Slightly downplayed, but the team suffers from this twice over. Every one of them is a Long-Range Fighter both by training and necessity, and unfortunately for them, most Terran ranged weapons (with the exception of grenade launchers) are unusable by people from Earth.
- Marrion Zimmer Bradley: In The Colors of Space, humans need to be in stasis to use the FTL drive. Or so the aliens who invented the drive claimed.
- Chanur Novels: The hani ship has recessed controls usually operated by the hani's retractable claws. Tully has to come up with a work-around.
- Heechee Saga: The vessels left behind by the alien Heechee have V-shaped seats which are uncomfortable for human crew.
- The Madness Season: The eyes of humans and Tyr respond to different frequencies of light. Because of this, all of the helpful labels that Tyr spacecraft use are completely invisible to humans.
- Call of Cthulhu: Terror from the Stars. Mi-Go fire their Lightning Gun by grasping it and altering its electrical resistance. Humans have to clip one of its wires.
Tech requires a specific DNA sample (4)
- Dredd: Subverted. While she gets captured by Kay after a momentary lapse in concentration and she looks to be in utter terror when brought in front of Ma-Ma, she escapes on her own when Kay tries to use her Lawgiver on her. She subsequently rearms herself, kills a few Mooks and actually rescues Dredd when Lex has him dead to rights.
- Nikolai Dante: Anyone who hasn't got their geneprint coded to the Huntsman 5000 that tries to fire it ends up with the bullet turning around and hitting them in the face. This includes telekinetic psychics that aren't even physically firing the weapon themselves.
- Judge Dredd: The fact that a Judge's weapon can only be used by that particular Judge or someone sharing that Judge's DNA becomes a plot point.
- Tropes M to P: The Judges' DNA-encoded Lawgiver cannot be used by anyone else. Unlike the 1995 movie however, they explode and can tell if a clone sibling is using it, since in the comics clone Judges are common.
Tech requires a specific fantastic trait (5, one is Fridge)
- Game Theory (Lyrical Nanoha): The glyphs on the Garden of Time give anyone who looks at them headaches, which Yuuno theorizes is the result of them being intended to interface with engineered mental structures that the Alhazredians would have had but no one else does.
- GaoGaiGar: A relatively minor one: Seeing how the series likes to point out the flaws with its tropes, then make them work anyways, you may wonder why Mikoto's a fairly standard operator pre-Zonuda, but then it hits you: GaiGar, GaiFar, :and Genesic GaiGar don't have keyboards in their cockpits during Fusion, so they need someone on the other end to calibrate the GaoMachines for the current situation, and even if they did, the pilot still wouldn't be able to operate the other GaoMachines from within the Mechanoid until after Fusion (Fusion only allows direct control of the mech they're piloting, and neither Galeon nor PhantomGao have a way to remotely control the other Machines. The pilot literally can't activate it themself. This begs the question of whether this is standard, or whether it's because the usual pilot's not from the Green Planet. Going by what we see in the first few episodes of FINAL, it's likely that people from the Green Planet can execute Final Fusion without an operator, it's only Guy that can't.
- Darkover: In The Heritage of Hastur, the Sword of Hastur is protected by two force fields. Only a telepath can pass through the first one, but only a non-telepath can pass through the second one.
- New Jedi Order: The New Essential Guide To Vehicles and Vessels mentions that the Skywalkers modified the bridge airlock on the Jade Shadow so that it could only be activated from outside if one used the Force to operate the internal mechanisms.
- Tropes Nto R: With the exception of the replicator wand in "Onion Trade", Gem technology (most obviously Warp Pads) can only be activated by gems and lays dormant otherwise. It's unclear if this is a deliberate feature or accidental, but the result is ancient-looking high technology sitting around the Earth unguarded for thousands of years without any human reverse-engineering.
Non-humans can't use human tech (3)
- Shining Force: Implied; Gong is first seen chopping wood with an axe, but when he joins the Force, he leaves behind his axe and fights exclusively bare-handed. Supplementary materials state that Gong is a half-giant, indicating his hands might be too big to use axes in combat as effectively as dwarves; thus, he would only use them for tasks where they are specifically required (i.e. splitting wood).
- Star Wars Legends: Races: It's stated that Ssi-Ruu paddle beamers (and other technology) are utterly incompatible with Human technology due to their unusual life-force powered energy cells.
- Atomic Robo: Since he's a robot with non-human fingers, Atomic Robo can't operate a touch screen at all. In one scene, he's actually seen complaining to Steve Jobs about how useless the iPad is to him - and attempts to justify further research by stating lots of people are coming back from overseas with Artificial Limbs. Later, when Robo has to answer a call on a smartphone, he literally can't, for the same reason.
Tech doesn't work if you don't have the same body shape as the designer's species (5)
- EV Nova: United Galactic Federation: Due to their intended operators being nearly three meters tall and having two thumbs per hand (the other one being where the pinkie is on humans), Varellavite starship cockpits have to be modified for most species. Same goes for ships built for the tentacled Ta'cural'th, the spider-like Lanvar-Ozians, the base 14-using Klavarese, the taloned Balcrusians, or any number of other species.
- X: Khaak ships can't be boarded in TC, probably because of Operator Incompatibility: as per the encyclopedia, individual Khaak are only 80 cm tall (the average humanoid is about twice that).
- The Pentagon War: Workstations designed for Centaurian use will have 360-degree video displays, surround keyboards, and pedals that accept input from the biological wheels in the user's feet — but will never, ever have a 3-D display.
- Star Trek Enterprise S 03 E 18 Azati Prime: When walking Archer through the controls of the Insectoid ship, Travis notes how hard they are to operate, and Archer suggests that they're probably made for a pilot with compound eyes.
- Muundeis Adoptables Dos: The Boxor actually can't be piloted by most of the Pantheon's deities due to the size of the cockpit. As such, besides Matoran (of which there are none) and maybe Turaga (those who used to be the Toa Metru), the only races capable of piloting it are halflings, goblins, dwarves, those who can downsize or shapeshift to the appropriate size, and other similarly-diminutively-sized entities. This also unfortunately includes children, which neither Nuparu nor Whenua are receptive to and will be quick to stop, and both worry the GUAE may desire to copy the design just for that purpose.
Differences in body type that exist without there needing to be multiple species (1)
- Darkover: Noted in The Forbidden Tower: Terrans, who are usually right-handed, often have trouble using implements designed by/for Darkovans, who are usually left-handed.
Zero context (3)
- To the Stars: Dangerous technology will only work for authorized users.
- The Adventures of Buckaroo Banzai Across the 8th Dimension: Buckaroo has some difficulty flying the Red Lectroid Thermopod thanks to this.
- Liaden Universe: Val Con trying to fly a Yxtrang ship.
- The Truce at Bakura: Dev's ion paddle beamer is custom-built for him as he cannot use the standard Ssi-ruuvi ones.
Not actually examples (2)
- Atomic Robo: I read the example for Operator Incompatibility and wondered why Robo didn't just use the tip from a commercially available iPad stylus.
- Character Archetypes: not Shielding (listed as one of Jaller's portfolio tropes under The Toa Inika)
Human bodies function in lots of different ways. They can differ in height, weight, handedness, number of limbs, possession and functionality of artificial limbs, which senses work, and more, and all of these differences will change how someone uses technology.
Speculative Fiction introduces even more potential bodily differences for characters. They could be made of different materials or covered in fur or scales, have body parts no human naturally does such as tails, wings, or tentacles, change body shape for varying reasons, be sizes completely outside of the human range, have senses humans don't, or shut down certain kinds of tech by their very presence.
Because of the wide variety of body types and functionalities potential operators can have, designers of technology have to put a lot of work into adding accommodations so that everybody can use it. When they don't, you get this trope where characters have trouble using tech designed for someone (or something) with different body types or functionality from them. This can range from a left-handed character not being able to efficiently operate a right-handed computer mouse to humans being unable to see, let alone operate, the controls for spaceships built by Starfish Aliens with Bizarre Alien Senses.
In certain settings, Finagle's Law ensures these differences will cause disaster. Sure, sometimes it's a bonus, or even a built-in feature, that the alien saboteurs can't use the Artifact of Doom properly, but usually it's just a pain.
If a piece of technology only works for one specific user, that's Loyal Phlebotinum.
Supertrope to Human Furniture Is a Pain in the Tail, specifically covering characters having trouble with furniture built for someone else's anatomy.
Compare and contrast Appropriate Animal Attire, Disability Immunity, Phlebotinum-Handling Requirements, and Dream-Crushing Handicap.
