Key considerations when working on HMI design projects

By Daniel Nunn, Senior Software Engineer, ByteSnap Design

AI's role in advancing Human-Machine Interaction

Natural Language Processing (NLP) and machine learning technology is driving the ability to interpret, manipulate and comprehend the human language. This means AI-powered, voice-controlled systems like Siri, Alexa and Google Assistant are now more personalised and context-aware, so users enjoy more realistic communication with them. New developments such as depth-sensing cameras and advanced gesture recognition are creating evermore interactive and immersive experiences across various applications and sectors that demand safer, user-friendly controls. Virtual reality and automotive design are good examples.

AI integration is also significantly improving accessibility in HMIs. Anyone with a disability will have new ways to engage with systems through enhanced voice controls and adaptive interfaces. In the near future, we can expect to see more advanced predictive text features, real-time captioning and increasingly responsive voice assistants.

However, embedding AI into HMI systems is no small feat for engineers. Optimising AI models for efficient performance within the limited processing power and memory of embedded systems is a major hurdle for engineers.

Data privacy and security are also critical concerns, especially as AI-powered HMIs often handle sensitive user data, along with engineers having to develop systems that can handle different user inputs, like accents and languages, all the while maintaining high performance despite varying environmental conditions.

Augmented Reality (AR) in Human-Machine Interfaces

Augmented Reality (AR) is enhancing HMIs, particularly in automotive, healthcare and industrial manufacturing, by overlaying real-time data onto the user's environment, providing instant, relevant information.

However, AR systems require robust protection against breaches. Additionally, the variability of real-world conditions poses a significant challenge. AI systems must handle diverse user interactions, including various accents, languages and unpredictable environmental noise, which can affect the accuracy of voice-controlled interfaces. Engineers need to develop adaptable and resilient AI models that maintain high performance and user experience in these different contexts.

AR is delivering significant advances for HMIs in areas like workplace safety. AR can provide instant machine information and allow for the safe practice of emergency procedures. Real-time data overlays in AR applications project current system data onto real-life environments, ensuring users have up-to-date operational information.

For example, in the automotive sector, AR-integrated heads-up displays (HUDs) can project navigation and vehicle diagnostics details directly into the driver's field of view, enhancing safety and convenience.

In healthcare, AR improves procedural precision by overlaying critical data during operations and training, enabling greater accuracy. Industrial settings benefit from AR through real-time maintenance instructions and diagnostic data on equipment, improving efficiency and reducing errors.

The integration of AR into HMIs introduces several complex challenges for engineers. Achieving real-time performance with low latency is crucial for maintaining the seamless overlay of digital content onto real-world environments.

AR applications for embedded systems are often constrained by limited power. Precise calibration is crucial for accurate digital overlays but can be challenging in dynamic or uncontrolled environments. User-friendly interfaces that seamlessly integrate AR and non-AR inputs are essential for broad adoption. Privacy and security are major concerns, as AR HMIs might access and display sensitive data in public spaces.

The rise of touchless interfaces

Contactless interfaces are also growing in popularity and demand – so much so that United Airlines has a "Touchless ID" system that allows passengers to navigate airport security using facial recognition. Touchless technology is becoming an essential tool in various sectors, from healthcare—where it helps maintain sterile environments—to retail, where contactless payments are now the norm.

As AI evolution and development continue, it will increase touchless systems, improving voice recognition and facial recognition accuracy. However, integrating touchless technology into HMI systems brings its own set of challenges, including the need to optimise sensor integration, reducing latency to enhance responsiveness, and ensuring consistent performance. Engineers will also need to address data security and privacy concerns, particularly when handling biometric data.

Haptic feedback: a tactile dimension in digital interactions

Haptic feedback adds a tactile dimension, so users "feel" digital interactions through vibrations, for example. Smartphones and gaming controllers are just two devices that have haptic technology but it is making its way into new areas. In surgical training, haptic feedback is used to simulate the sensation of operating on different tissue types, helping trainees develop more precise motor skills.

The global haptic technology market size was valued at £3.3 billion in 2023 but is projected to reach over £10 billion by 2032, growing at an impressive CAGR of 14.9%, driven by advancements in actuators and control algorithms. Haptic technology is also finding applications in sectors like aviation, where pilots use VR systems with haptic feedback for training, and automotive, where haptics enhance driver-assistance systems.

Integrating haptic feedback into embedded systems brings engineers several challenges, including managing power consumption, integrating haptic components into compact devices and ensuring low latency for realistic feedback. Cost considerations are also a factor, as haptic technology adds to the overall production expenses. The increasing cost continues with the need for extensive testing and validation, ensuring design durability and reliability of the actuators, so the haptic feedback truly enhances the user experience without causing any confusion or discomfort.

Conclusion

The face of Human-Machine Interfaces is rapidly changing. As AI, AR, touchless technology and haptic feedback converge, we are experiencing a shift in how we interact with machines. These technologies unlock new possibilities, offering more personalised healthcare experiences, intuitive car controls and secure interaction with devices. However, unlocking the full potential of these possibilities requires collaboration. Engineers, designers, user experience experts and cybersecurity specialists need to work together to create seamless and secure HMI solutions. With continued refinement, these technologies will only enhance human-machine communication, pushing the boundaries, making HMI interaction efficient and effective, and shaping the future of digital interaction.