Smell And Vibration Tests

Two-channel vibration motor test – equal-power panning (used in audio) applied to two vibration motors and controlled by a joystick

Testing different papers for asborbing essential oils for a smell-based videogame (handmade paper worked the best, bristol board the worst)

Absorbing scents overnight in a plastic bag

Testing a smell-release valve using a very small servo motor, a round valve with soft foam gasket, and controlled by an Arduino

Door “Oof” In Doom And Thoughts On UX Design

When the PC game “Doom” came out in 1993, my dad brought a copy home from work. I don’t think he realized how violent and full of satanic imagery the game was (to my happy surprise) and I spent way too many hours playing the game. Not having much access to videogames as a kid, Doom and a few others (Super Mario Brothers for NES, Tetris on the original Game Boy, Sonic the Hedgehog, Mattel Football, Pitfall for Intellivision) remain my reference points when I think about games.

Early experiments toward a series of haptic and non-visual games have led to a realization: a single type of feedback in a game generally results in a flat, non-immersive experience. An animation of a gun firing with no gunshot sound is still believable and playable, but with that extra feedback of the gunshot sound the game becomes realistic, and we suspend disbelief and fall into the game. But another type of feedback has struck me as deeper, effecting not just the enjoyment of a game but actually driving the UX design and clarity of the gamespace and its rules.

A case study can be found in Doom: in the game there are two types of doors, ones that you can open any time and ones that require keys (picked up elsewhere in the level). Upon reaching a door of either type, the player presses a key on the keyboard to try to open the door. If you have the key or the door doesn’t require one, it opens with a satisfying “swoosh” – like a gunshot, this sound adds to our immersive experience. However, when the player attempts to open a door without the proper key, nothing happens visually but the character emits a loud “OOF!” sound.

The “oof” is key: without it nothing would happen at all and we would be left wondering “did I press the right key on the keyboard? Is this a door at all?” The above videos demonstrate this in the game – the first is normal gameplay, the second with the sound modified so there is no “oof”. While this translates in video, actual gameplay is really required to fully appreciate the difference a single sound effect can make on an interaction.

This question originally arose while developing the badge for the 2012 Games++ event, where the only feedback for navigating a dungeon space was a vibrating motor. With each tile-type (sand, stone, etc) as a unique vibration pattern, the question became: what about walls? Should there be a vibration when you can’t move in a particular direction? What does no vibration signify? We decided on no vibration, which gives the added possibility that someone might invert the level in their mind’s eye, seeing walls as pathways and other tiles as walls.