Improving Motion Activated Sinks
Everyone uses sinks every day (I hope). They’re a routine part of our day, so they should be able to operated quickly and without much thought. Along with using sinks often, we use many different sinks — any place that you go and use the restroom, you will use a sink there which is likely different in some way from other sinks you’ve used that same day. Sinks therefore need to focus on learnability rather than memorability because users will often be encountering a new sink and just using it once, as well as the fact that sinks are overall rather simple and it’s not very hard to remember how to turn on a particular sink.
The only reason that this is a topic of discussion at all is that many sinks now rely on motion sensors to turn on, and they do so with varying degrees of success. There are two issues. One is that it’s not always clear when is sink is motion detected or where you should hold your hand. The second is that the sensors will often not be accurate enough, so if you’re holding your hand in the optimal washing spot the water may not turn on or it may even turn off while you are washing.
There are definitely valid reasons for the sink being this way. It is likely the cheapest and simplest option to have one small centrally located sensor that sacrifices some accuracy for the sake of a better price. Additionally, it is visually sleek to have the sensor embedded right into the sink head and not have any extra parts sticking out. My proposed solution, shown below, is actually less aesthetically pleasing but I believe it has much better affordances.
I propose adding large sensors, separated from the sink nozzle, on both sides of the sink. I think these sensors would fix both identified problems. They are very visually obvious so the user would now that that this is a motion activated sink and where the sensing is done from. The larger sensors would also allow a better range of activation that would provide the expected behavior of turning on the water whenever your hands are under the nozzle.
The large black sensors may not be aesthetically pleasing, so there is some visual drawback. However, I imagine this as a solution for public restrooms, where ease of use is a priority and the sinks don’t really need to be pretty. A home sink would not need to implement this both because those are used by the same people repeatedly so they know how they work, and also because home sinks probably use handles anyway. For a public restroom, on the other hand, this change would make sinks more learnable and satisfying to use.