Observation Experiment: Cash Register

For this assignment, I observed a cashier interacting with a touchscreen cash register at the dining hall. This is an interaction that most of us witness multiple times per day, and it also is an interaction that is very time sensitive. How efficient is this interaction, and are there places for improvement?

the following video records the interaction:

Immediately, we can see that the cashier is very skilled! The whole interaction involved many individual touchscreen presses, all over the screen area, and yet the interaction only took about 10 seconds! It is all the more interesting, then, to see where the hiccups were, and try to suggest solutions for those.

Clearly, the cashier is not reading the button labels, relying instead on memory to press the button that corresponds to the customer’s food. The cashier does have to stop and read the labels at one point, though, and that is to find the Diet Coca Cola Can button. Finding this button is easily the single most time-consuming activity the cashier does – surely, there must be a better way to facilitate interactivity? Perhaps it is impossible to obtain muscle memory of all the different drinks, because there is just too much variety? In that case, we should make the buttons look more like the soda cans, to make it easier for the cashier to identify the correct button at a glance.

This is where I discovered another design for the cash register interface:

The reason why I think this interface would be better than the text-only one that our dining hall is currently using, is that this interface makes the buttons look similar in design to the design of the soda cans that customers might bring – and thus makes it easier for the cashier to spot the correct button, making the interaction even more efficient than it already is!