Should bionic limb control mimic the human body? Impact of control strategy on bionic hand skill learning

Area of Science:

• Biomedical Engineering
• Neuroscience
• Human-Computer Interaction

Background:

• Designing anthropomorphic bionic limbs that mimic biological control (biomimetic) is a long-standing engineering goal.
• It is assumed that biomimetic control enhances embodiment, learning, generalization, and automaticity in users.
• However, the effectiveness of this assumption has not been empirically tested.

Approach:

• This study compared biomimetic and non-biomimetic (arbitrary) control strategies for able-bodied participants learning to use a wearable myoelectric bionic hand.
• Participants were divided into two groups: Biomimetic (mimicking gestures) and Arbitrary (unrelated gesture mapping).
• Motor learning was assessed across multiple days and behavioral tasks.

Key Points:

• Both biomimetic and arbitrary control groups showed improvements in bionic hand control, reduced cognitive load, and increased embodiment.
• Biomimetic control offered more intuitive and faster initial learning.
• Arbitrary control users achieved comparable performance later in training and demonstrated superior generalization to novel control strategies.

Conclusions:

• Biomimetic and arbitrary control strategies offer distinct advantages for bionic limb use.
• The optimal control strategy is likely not strictly biomimetic but exists on a spectrum, adaptable to user needs and training.
• Future designs should consider flexible control strategies tailored to individual user requirements and learning contexts.