Built to Last: Five Best Practices for Building Reliable HMI

Twenty years ago, industrial workers used simple HMIs with one piece of software until the product expired. Today, smartphones are setting new standards for user experience, and the digitally native workers expect sophisticated interfaces that mirror smartphone functionality as a bare minimum—even in factory environments.

According to GSMA, 53% of the world’s population were smartphone users at the end of 2023. This partly explains why even companies developing HMIs for industrial environments try to create app-like interfaces that meet workers’ new UX expectations. At the same time, they also try to replicate full app ecosystems similar to Google’s Play Store or Apple’s App Store so that partners can easily extend software functionality across the factory floor.

With factories becoming more modular, HMI development will need to factor in scalability and interoperability between different environments.

Whether it’s a control panel for operating heavy machinery or a handset monitoring the security of a power plant, HMI designers should aim for a consistent and scalable architecture.

• A consistent architecture comes from using well-established technology for all your HMI components and modules and aligning your HMI software design, architecture, documentation, and source code.

• A scalable architecture is hardware agnostic and can be used across a range of diverse hardware systems, including those currently under development. 

Consistency and scalability are crucial to ensuring long-term software reliability and advanced functionality, as they enable you to:

• Adapt to the latest trends: From embedding new AI models to adapting to new hardware, ranging from heavy machinery to mobile screens.

• Work with multiple partners: Using well-established technology makes it easier to plug them together and enables numerous partners to work collectively on your HMI.

• Lower maintenance costs: Aligning all the key parts of software production makes it easier and cheaper to maintain software in the future.

Software consistency not only simplifies the maintenance work, but also helps new developers and customers reuse previous software components and modules, easing thus extensions and integrations.

Developers and designers can work better together to optimize HMI performance—both in the short term and long run—by following these five best practices:

1. Componentize your architecture: Don't create a monolithic solution. With encapsulated modules, you can easily make updates throughout the HMI’s lifecycle, such as tweaking IoT protocols or adding high-level data visualization.

2. Make your backend independent: Create two clear interfaces for your backend and frontend. If your backend is separate, you can update the UI layer without changing the backend.

3. Keep a secure environment: Empower app encapsulation. This allows you to create sandbox applications in a way that maintains a secure environment, even if others are contributing to your ecosystem of apps.

4. Adopt a shift-left approach for testing: Instead of fixing errors post-release, detect and resolve errors earlier in the development process, moving from the release phase back to implementation, testing, and even to architecture design and verification. By catching errors early, you avoid the high costs of fixing them later, reduce time to market, and enhance product security.

5. Choose long-term support: Select mature technology from partners with a strong production history. To ensure your HMI works reliably for 10-20 years, you need a trusted partner who provides maintenance and support in the long run.

When you are developing an industrial HMI, focus on extensibility and long-term support to keep up with the latest trends in the market and ensure your software functions effectively for the next 20 years.