Human Factors and User Interface Class Project

Project 5

Usability Test and Interface Re-design

This project is to design a revolutionary, intuitive, and absolutely unique interface for a currently non-existent system. This system will be constructed as a Senior Design Project at South Dakota State University. When it is completed it will have the ability to mix beverages with any combination of the sixteen liquids contained inside it. As there is no current system this will be a complete and one-off design from nothingness.

Overview and Problem Definition

This project will be to design a User Interface for the Self Contained Automatic Beverage Mixing System or S.C.A.B.M.S. This system is currently not in existence so this User Interface will be the first of its kind. Its aim will be to be both visually pleasing and highly functional at the same time. This will be accomplished by using common visual elements to convey action for instance elements that a user may encounter in their everyday life that with no instruction they simply know what steps to take to achieve the desired outcome.

Design is not just what it looks like and feels like. Design is how it works.   — Steve Jobs, 2003

This Interface will need to be straight forward, intuitive, and easy to use. The system is not aimed at any particular demographic so the users will have varying levels of technical knowledge as well as very varied ages. For all practical purposes we will assume that the users are not visually handicapped and are able to use at least one of their arms / hands.

Usability Test

Scenarios / Interviews / Observations


I Interviewed three users and had them run through a few different scenarios using my system. These scenarios were to:

I simply gave my users the interface and the above list of tasks and observed what they did.

My test users were:

Name: Karla Fernholz
Age: 43
Technical Background: Average to Below Average

Karla made it through all of the tasks with relative ease, she said that the interface had a great flow and the controls were really intuitive and easy to follow. She need a bit of explanation as to how the Add Drink function worked (as in how to choose the ingredients). Other than that one issue it went quite well. I did notice that she would usually go to the Main Menu instead of just going back to complete the three tasks involving a drink selection, although this is not an issue as it works just fine that way, I just thought it was interesting.

Name: Barry Whipkey
Age: 22
Technical Background: Average to Moderate

Barry had a pretty easy go at it as well after acclimating himself with the menus by just simply clicking around a bit. Once he was done inspecting the different menus he set off on the given tasks. The three tasks involving drink selection were a breeze as he made use of the back option to simply toggle back to the drink selection screen and choose the next option on the list. (I was glad to see this) Barry likes to play around a bit, so when customizing his newly created drink he decided to see what would happen if you ran one ingredient all the way up. This uncovered a bug in the system that, once you try to change another value you get a NaN (not a number) error in the text field. I was glad to see that without prompting he simply hit the reset button and tried again. He had no trouble at all with the Clean and Prime options whatsoever.

Name: Dave Freitag
Age: 23
Technical Background: Expert

Dave had an unfair advantage in my test field as he is a co-developer of this system, but he has not been involved directly with my User Interface Design, so I thought I would let him have a go at it. Well, Dave flew through most of the tests, but like Barry, Dave likes to test the limits (and I think he was out to try to break it) and he also found the error that happens when you run one ingredient all the way up on the customization screen. Like Barry, he was able to easily remedy the problem by hitting the reset button and continuing on.

Summary

Overall I was very pleased with the results of this Scenario Testing. I was able, with the help of my testers, to uncover a bug in my customization screen and I was also pleased to see that the users were able to intuitively remedy the problem on their own. I was also glad to see and hear that the users thought the system had a very natural flow and they were able to navigate through the tasks with relative ease.

Interface Redesign

Upon completing my observations I only saw one major thing that needs to be changed and that is the error that occurs when a user runs the value of one ingredient all the way up. I will add in some additional logic to accommodate for that. Another minor issue will be to add in some more descriptions and help features, which as I've stated in my status report I ran out of time on implementing. Other than that the system seems to be a success and my users can't wait to use the real thing.

Long Manual

Figure 1: Main Menu -> Drink Options Flow Chart Figure 2: More Detailed Drink Options Flow Chart


Main Menu -> Drink Options


There are a few different paths through the system that involve selecting a drink, below are the steps for each:

Figure 3: Main Menu -> Add Drink Flow Chart


Main Menu -> Add Drink


These steps will detail how to add a new drink into the database.

Figure 4: Main Menu -> Clean System Flow Chart


Main Menu -> Clean System


These steps will allow you to clean the system.

Figure 5: Main Menu -> Prime System Flow Chart

Main Menu -> Prime System


These steps will allow you to clean the system.


Discussion

Now that this project has come to a close I have just a few things to say. I really like the interface I've created and the response from my classmates, family, and friends has been completely positive which makes me feel good. I did spend a little too long on a few of the functionalities and this caused me to run out of time and I had to sacrifice a few of the functionalities that I originally sought out after, namely, the Help and Search / Sort Functions.

It will be exciting to see this at the end of this school year in a real and working environment. Trust me this is not the last you've hear of the SCABMS.