Ultrasound-Based Human Machine Interfaces for Hand Gesture Recognition: A Scoping Review and Future Direction

Since ultrasound signal is firstly used to build a human machine interface (HMI) for prosthetic control in 2006, ultrasound-based HMIs have received the great attention in the past 18 years. In this paper, I provide a comprehensive overview of every aspect of an ultrasound-based HMI for hand gesture recognition (HGR). Firstly, I introduce the principle of ultrasound-based HGR and then outline a workflow for an ultrasound-based HMI for HGR and detail each step involved in the workflow, followed by an introduction of performance evaluation and robustness of this type of HMI. Then, I review the research progress of ultrasound-based HMIs for HGR. After that, I introduce the state-of-the-art wearable ultrasound systems for HMIs. Furthermore, I summarize the miscellaneous application of ultrasound-based HMIs for HGR. Finally, I discuss the main research challenges and further envision future research directions for ultrasound-based HMIs for HGR.