The first part of this article provided an overview of the concepts of the currently implemented user interfaces for the Kinect™ sensor. It pointed out technical specifications and explained the human-machine interaction within Kinect games. This second part now scrutinizes this interaction and assesses its potential for industrial application.

In November 2010, Microsoft® introduced Kinect™. As an expansion of the Xbox 360™ gaming console, it brings controller-free gaming to the living room and even long before its actual release it was believed to revolutionize Human Computer Interaction. Therefore, expectations were rather high and one felt reminded of the Natural User Interface (NUI) featured in the movie Minority Report. Will this futuristic vision soon become reality?

Keeping the background information of the previous article in mind, assume you want to make use of Blend to design a NUI based on Silverlight or WPF that lets you easily manipulate items on the screen. In the beginning, you won’t even touch the tool at all – you “invent” whatever gesture you think is intuitive to perform this operation. Most likely you do this in your head or on the whiteboard. You discuss and refine the design with your team mates or with potential users. At this stage everything is still low-fidelity and throwing away things isn’t costly yet. As soon as you have a good-enough feeling about the rough design, you start prototyping with higher fidelity. This is to be really sure your idea works. To provoke the intended interaction experience, caring about every single detail is exceptionally important in later prototyping stages.

Every user interface designer is familiar with the procedure to some extent: To find out what a user interface needs to look and behave like it’s certainly a good idea to create a prototype and evaluate it with potential users. Users will tell you what’s still nagging them and therefore should be improved before coding starts. So, in the beginning of any UI design process everything is about change – you create a prototype and already expect it to require modifications in order to work alright. As you – and most likely your client, too – want changes to be as cost-efficient as possible, you are better off taking a change-friendly prototyping method or tool. This is especially true in early stages of the project your ideas of potential solutions are rather vague. In this early phase, most often you don’t even know the exact problem for which you are in hunt of a solution. You are still analyzing more than you are designing.

User interface prototyping is an essential activity in the field of user interface design that provides a basis for continuous evaluation and improvement of a to-be-designed user interface. In usability engineering, the focus of using prototypes lies on evaluating the usability of intended approaches and on generating concrete recommendations for advancing an interface design. While doing so, there are several aspects to keep in mind in order to maximize the efficiency of prototype use for usability engineering. Three issues are described in this post.

Wireframes are an essential tool in the usability engineer’s toolbox. They can be created easily and support communication regarding fundamental layout and interaction design. Usually, little to no resources are spent on visually “styling” the wireframe in order to efficiently focus on the fundamentals without investing too much effort in visual details that are likely to undergo significant visual changes later.

If members of the design team / stakeholders lack experience with using wireframes, certain problems can occur that may impair a user interface design project, two of which shall briefly be described.

“Who needs usability engineering, anyway?” – This is a question that one might hear from people whose experiences with usability engineering services have not been too good.

An essential part of designing user interfaces consists of communicating about system behavior and functionality that has ultimately to be provided in the user interface in a user-friendly manner.

To transfer knowledge regarding system behavior / system functionality, a variety of methods can be used. Often, use case descriptions and screen scribbles are employed to provide the required information. When a user interface designer has a kickoff meeting for a project, for example, a stakeholder can scribble a screen that would provide essential system functionality so that the user interface designer gets a quick impression of certain system aspects. During requirements engineering, use case descriptions might have been created that are handed to the user interface designer to get a feeling for workflows that are carried out and the desired user-system interaction.

Both ways of documentation have their advantages and drawbacks.