HCDE 451 // A1 Process Blog: Electric Screwdriver

PromptFor the A1 prototype, I was tasked with designing a handheld electric screwdriver with a variable speed control and digital display allows you to auto-select screwdriver shape and size. The requirements are as follows:variable speed control you decide the mechanism/interaction and whether it is fluid or distinct settingsscrew-driver selection mechanism (either digital or non-digital your choice) allows you to automatically select and switch between either Phillips or flathead shape and five different sizes of each shape (for 10 total screwhead choices)screw-driver direction selection mechanism (non-digital) to either screw in or unscrewdigital readout (monochromatic, non-touch sensitive) of number of screws screwed and screws unscrewed for tracking your progress as a handypersoncan be used right or left-handedproduct dimensions are a minimum of 6 inches long and must be able to contain a rechargeable batteryDesignOXO is a brand well-known for their easy-to-hold kitchen utensils and office supplies. Originally designing for people with arthritis, the founders of OXO aim to create products that are usable for anyone using their tools.

With this in mind, I began to sketch the various screwdriver features. I thought of the various ways I could create affordances for the different parts: twists, buttons, knobs, wheels, digital displays, etc. I took into consideration the approximate size of about 56 inches and chose to place most of the features at the top of the screwdriver in such a way that the user would be able to hold it and view all their settings at the same time.

I knew I wanted to incorporate a rubber grip and a circumference that would make the product easy to hold, so it was just a matter of choosing which affordances to select for the various features.PrototypeI decided that the features on the screwdriver would have to be consistent. Using too many different affordances (twists, buttons, etc.

) could be confusing. I chose to focus on a twist-based selector for the screwhead and size selectors. This was space-efficient and fit easily above the main part of the grip.

I put in a small display towards the bottom of the handle, and placed the battery compartment at the base. The on/off buttons on the main part of the handle where it would be easily reachable.This prototype was built primarily out of cardboard from the Comotion Makerspace at the University of Washington.

After cutting sheets of cardboard into rectangles, I was able to cover them in construction paper and roll them up to create a round handle and the twist-selection features of the top of the screwdriver. I drew icons on dot stickers and used them as labels for the settings on the screwdriver.Usability Testing at Home and in ClassI first tested the prototype with my sister, asking her to change various settings and pretend to screw things into a bookshelf.

A usability test video clip of my sister could be found here. I was also able to gather feedback during a critique session in class where I was able to demonstrate and test my prototype with 11 different people. They wrote down their comments and suggestions on sticky notes.

Findings and AnalysisAfter testing the prototype with a total of 12 people, the general consensus for what went well are as follows:Users appreciate the visibility of the various options on the screwdriverThe consideration to detail and placement was something users enjoyed and found made the prototype easier to understandAfter a quick demonstration of how to use the screwdriver, users found it intuitive and easy to understandHowever, it was clear that some parts needed improvement:The fragility of the prototyping materials made users hesitant to twist and turn parts of it with the fear that they may break it (as seen in the video above where my sister was reluctant to twist the top part of the grip)Some users found the icons confusing, and the labeling overall could be improved (such as changing speed settings 1, 2, 3 to slow, medium, fastA tapered tip could help guide the user to where they were screwing in the bitsI found that the overall design was effective, but it required minor tweaks to improve the clarity of what particular parts of the screwdriver do. With my limited type of materials, users found it difficult to determine which parts they could press: one user asked, Are the round icons digital or just labels?If I were able to create a second iteration of this prototype, I would consider using more varied materials, perhaps using shinier materials for buttons that clearly distinguish those affordances from other parts of the screwdriver