Preliminary Assessment of Two Simultaneous and Proportional Myocontrol Methods for 3-DoFs Prostheses Using Incremental Learning

Despite progressive developments over the last decades, current upper limb prostheses still lack a suitable control able to fully restore the functionalities of the lost arm. Traditional control approaches for prostheses fail when simultaneously actuating multiple Degrees of Freedom (DoFs), thus limiting their usability in daily-life scenarios. Machine learning, on the one hand, offers a solution to this issue through a promising approach for decoding user intentions but fails when input signals change. Incremental learning, on the other hand, reduces sources of error by quickly updating the model on new data rather than training the control model from scratch. In this study, we present an initial evaluation of a position and a velocity control strategy for simultaneous and proportional control over 3-DoFs based on incremental learning. The proposed controls are tested using a virtual Hannes prosthesis on two healthy participants. The performances are evaluated over eight sessions by performing the Target Achievement Control test and administering SUS and NASA-TLX questionnaires. Overall, this preliminary study demonstrates that both control strategies are promising approaches for prosthetic control, offering the potential to improve the usability of prostheses for individuals with limb loss. Further research extended to a wider population of both healthy subjects and amputees will be essential to thoroughly assess these control paradigms

Executive control in a Mixed Reality exergame for motor-cognitive rehabilitation in multiple sclerosis

Nowadays, rehabilitation procedures for people with multiple sclerosis (MS) are supported by an increasing number of tools. In particular, interactive settings have gained attention in this domain, showing promising effectiveness in motivating patients during repetitive rehabilitative activities. The aim of this work is to enhance traditional exercises through recent innovations in mixed reality (combining real and digital elements in the same setting, making the computer-generated items encrusted in the physical setting). This is achieved by developing an interactive environment where rehabilitation tasks are coupled with game-like features with augmentative audio and video cues. In this paper, the test setting focuses on upper limb rehabilitation, with a grid-like structure where the user must place a virtual cube according to a set of rules and constraints requiring the individual capability to control the execution of repetitive actions without violating specific limitations. This method is used to evaluate the performance and experience of users without MS through a series of playtesting sessions as preliminary tests, before involving people with MS. This study - also based on the comparison of two conditions of executive-inhibitory control - demonstrates how the engaging features of mixed reality can actively reduce the detrimental effects of repetitive exercises, further improving individual adherence to clinical procedures