A Case Study of the Car Steering Wheel Levers
For my first assignment in Tangible Research Studio, I picked the two levers next to my car steering wheel to study their interaction and tactile experience.
Note that my car is in Thailand, so the functions of the left and right levers are switched when compared to cars in the US.
Some questions I posed for myself:
How do they function?
What do they feel like?
What information do I get through sense of touch?
What do I do with this information?
What is unclear / can be improved about this interaction?
Right Lever
The right lever has multiple functions to control lights in front of the car, including turn signals, headlights, and high beams.
Turn signals function:
Flicking the right lever up turns on the left turn signal, and flicking it down from its original position turns on the right turn signal. There are two arrow icons to visually communicate this function.
Feels like: The motion of the flick itself is pretty effortless, allowing me to interact with just one finger while the rest of my hand still holding onto the steering wheel.
Information through sense of touch: The lever snaps to position once it hits a certain point, so there’s no need for me to gauge whether I’ve put it into the exact placement for not. I also feel and hear a click sound once it hits its trigger point, which is very clear feedback of state change. It also springs to its idle position, making a clear distinction between on and off.
I think this interaction is very intuitive as I am flicking the lever in the direction of the light I want to turn on.
Headlights & high beams function:
Twisting the rotary knob at the end of the lever turns on the headlights, as indicated by the light bulb icon. There are three modes within the twist, starting with off (idle), dashboard lights on, and headlights on.
Dashboard lights on
Headlights on
I can pull the lever towards my body to temporarily turn on the high beams. The lever immediately snaps back to idle position once I let go of the pull. I can also push the lever away from me to keep the high beams on, but only if the headlights are already on.
High beam indicator
High beams on
Feels like: Each step of the turn of the knob snaps in place, feeling and sounding with a click to indicate change of state. There’s a dip in the surface of the knob that fits my thumb. The knob also has a curve that aligns with the rest of the lever when it’s in idle position.
The pull of the lever does not lock in place, while the push does.
Information through sense of touch: The surface area for my thumb is a good indicator that it is meant to be held a certain way that is intuitive to a twist / turn. The curve that aligns with the rest of the lever is also a great tactile indicator of whether or not the knob is at its idle position.
The dynamic movement of the pull indicates that it is not meant to be a permanent state change, while the push that locks in place indicates otherwise.
Improvements: I remember not realizing what the middle step of the knob turn was, as I am usually looking out at the road when I twist knob. I would just go from OFF to headlights on, not realizing that I could turn just the dashboard lights on with the middle step. I’m not sure what would be a good way to improve this interaction, as there is limited space for visual communication.
Left Lever
The left lever controls the windshield wipers and washers. Flicking the lever up and down determines the speed of the wipers, ranging from mist, intermittent, low, and high speeds.
The washers will turn on for as long as the lever is pulled towards my body.
Feels like: The upwards flick to trigger the MIST option does not lock in place, making it a temporary state. Flicking the lever down from idle position keeps the wipers at the speed of indicated position, giving feedback through clicks. The pull of the lever is also dynamic and snaps back to idle position as soon as I let go.
Information through sense of touch: Similarly to the right lever, each speed position locks in place with a feeling and sound of a click, making it clear when the state as changed. The pull also bounces back on its own, indicating that the washers were are meant to stay on for an extended period of time. Unlike the right lever, the left lever does not have a push function. It feels like I would probably break the lever off if I try to push it forcefully, which tells me I’m not supposed to move it that way.
Improvements: There are no clear indicators of what speed I am currently at, aside from looking directly at the wipers. Sometimes I confuse OFF with INT, as there are no visual queues from the lever to tell me which state I am on. Perhaps adding visual markers like the ones on the right rotary knob, or a physical shape alignment like the curves on the right lever. Maybe playing with different feelings of click for each step could also be a good way to differentiate the speeds.