HMI Tools Save Time and Cost in Auto Applications

With the advances in graphics content for display-enabled embedded systems, efficient and easy-to-use HMI/GUI (Human Machine Interface/Graphics User Interface) tools are becoming increasingly important. Such tools enhance the system developer’s ability to input a design, develop and verify the application, and rapidly deploy it to the target system.

They help throughout the entire process—from rapid prototyping of user interfaces all the way to serial development of the embedded system—saving time and money. Almost as important, the tool needs to complete these steps easily and cost-efficiently, with a process flow that is as seamless as possible.

Some desirable traits of an HMI tool include cost effectiveness, seamless operation, separation of code and UI data, and system benchmarking. A specific tool from Fujitsu, CGI Studio, provides these benefits.

Tool Cost Factors

The HMI tool should allow early evaluation of HMI development. The tool should be structured to support design reviews, even in the early stage of the project. It should also conveniently support changes to the project implementation (such as graphics content) in the later stages of the project. All these factors contribute towards making the tool cost effective.
For example, the HMI tool should give a realistic preview of the graphics and scenes as soon as they are imported. This is implemented within the IDE of the tool and enables the designer to have a WYSIWYG view of the graphics. Another requirement is the ability to run and immediately verify widgets or business logic imported into the tool. This is only possible if the HMI tool has the capability to simulate graphics application on the host PC.

The HMI tool should allow changing the look and feel of the graphics without needing to recompile or rebuild the project (re-skinning). This can be achieved by separating code and graphics data from the beginning of the project. For example, from the outset of the project, the graphics designer can churn out 2D and 3D graphics using industry-standard tools such as 3D Studio Max or Maya. Independently of the graphics design, the software engineer can work on business logic to assign behavior to the graphic elements. The two elements can then be imported into the tool and verified together accordingly. If needed, the look and feel can be changed later simply by re-importing the new graphics assets without affecting the business logic.

Seamlessness
The HMI tool should have the capability to be easily integrated into the existing tool chain environment, and should be usable in all stages of application development. This results in a seamless process flow that brings many benefits to the table, including cost, easy tool management, and a common knowledge basis. The people involved in the project—the studio artists, technical artists, and embedded engineers—can focus on their individual roles. The studio artist can design the 2D or 3D graphics content in the industry-standard studio tools and can then use the HMI tool for preview. The technical artist can import that graphics content into the HMI tool and use the graphics to create scenes using appropriate lighting and composition. (The technical artist also focuses on the graphics, but his work is more hardware-aware than that of the studio artist.) Finally, the embedded engineer can add his business logic, which will assign appropriate behavior to the graphics elements as required by the application.




The tool chain should also support a flexible licensing model for use in a variety of situations, such as tool evaluation, rapid prototyping of a reference application, and product development. The user's cost should be based on need.

Separation of Code and UI Data

The HMI tool needs both the UI data (e.g., graphics assets such as bit map files, 2D/3D models, asset properties) and code that defines the application behavior. The code embodies business logic and could possibly be generated by a state machine tool or hand coded. In the latter case, the tool should allow the standard programming languages within the software community. The HMI tool should be structured in a way that the UI data is strictly separated from the code portion. The resulting advantage is the ease of changing the look and feel of the graphics without touching the code or needing to rebuild it. The old UI data in the tool output is simply replaced with the new data without rebuilding the entire application.