Grocery Store Reuseable Bag Brag Flag

In this project for my Interaction Design Studio, I worked to improve an interaction taking place in the
context of the grocery store checkout lane. Seeking to create better visibility for customers who bring their own reuseable bags to the store, I innovated a solution that utilizes the existing wand that customers use to separate their orders. My prototype aims to be minimally disruptive, open-ended so as to apply to many use cases, and also encourage behavior change.

Context: Grocery Store Checkout


I began by visiting the supermarket chain in my neighborhood, and observing the interactions that take place in both
the traditional checkout and the automated self-checkout. I also went through the lines myself (automated and traditional) in order to look at this simple experience with heightened awareness. Next I made an interaction inventory for seven specific interactions, noting attributes such as affordances and constraints (right).

I then honed in on one interaction in particular: placing reuseable bags on the conveyor belt.

This interaction has been a personal pain point in the past. When I actually remember to bring my own bags all the way into the store, occasionally the cashier or bagger won’t see them and will put my groceries in plastic anyways! It seems doubly wasteful and also discourages me from bringing them again.

Feeling inspired after reading the chapter on designing for politeness in Alan Cooper’s book The Inmates are Running the Asylum, I began sketching some ideas. I was interested in how his descriptions of software relate to human social skills: the ability to read a situation, provide perceptive and confident assistance, and then fade into the background until needed again.

In order to understand better how this interaction would play out over time, I sketched a quick storyboard of what could ideally happen while using this device.  Drawing out the interaction forced me to think about each step of the process and determine where my design might not fit in well.


Work in Progress Critique

The feedback from my peers and Raelynn O’Leary led me to question my design concept. They were concerned that the shape might tip over or be cumbersome to use. Up until then, I had been very concerned about how the reuseable bags would be contained, but with that feedback I realized that the importance of this interaction is not where the bags should go, but the fact that the bags are present! I decided to focus my idea on communication to the cashier.

First Prototype

To test my concept, I used some scrap wood and plastic to create a rough prototype. The awesome shop managers at the 3-D lab suggested that I try making the final iteration using the laser cutter.




Second Prototype

I created a pattern in Adobe Illustrator to be cut out of plexiglass on the laser cutter, and then painted, spraypainted and assembled the finished pieces. I decided to add the word “Lift” to the grip for additional discoverability.


Finished Prototype in Context

(or, Grocery Wand’s Big Adventure)

To see how the prototype wand might look in use, my classmate and I headed back to the supermarket to try
it out. At first, the cashier was a little wary of what we were doing, but when I explained the concept, he was very excited to hear about it. “I always put things in plastic by accident,” he said. He said something like this wand would help him to identify customers who had brought their bags.

One fault in the design I noticed immediately was that the clear acrylic flag got lost on the black conveyor belt! Rookie laser cutter mistake. For the next iteration I’d be sure to use an opaque white or another color.

Analysis of Concept

This design maps onto existing understanding of grocery store norms, and can function as a standard wand without any change or effort from the customer or employee.

When the flag is down, there is a a grip that sticks above the profile of the wand. This grip allows the flag feature to be discoverable by affording lifting. Additionally, the grip is curved so that it can function as a hook for bags, should the user wish to use it in that way. Once lifted, the flag itself contains the printed message of “I brought my own bags!”, which conveys to the customer’s intention to the cashier.

This image is taken from the cashier’s perspective. 

This object will work in the existing structures because after each customer, the flag can be lowered and then slid back into the track. Additionally, were this item to be put into production, its colors and typeface could be matched to the store’s existing brand.

Finally, the message on the outside of the wand, “Did you bring your own bags?” acts as a subtle reminder and nudge towards a more environmentally friendly behavior.

Next Steps and Final Thoughts

If I were to continue working on this design, my next steps would be to test it out with cashiers and customers and get their feedback.

Additionally, I would make some changes to the design. Not only would I change the material of the flag, but I might design it so that the flag ended up closer to the cashier’s side of the conveyor belt. Right now it is close to the customer (and therefore easy to lift) but is hidden from the cashier behind their computer screen.

I would also like to experiment with using moldable materials to make a handle that is round and more ergonomic instead of simply flat.