Design-validation of a hand exoskeleton using musculoskeletal modeling

Area of Science:

• Robotics and Human-Machine Interaction
• Biomechanics and Ergonomics
• Digital Simulation and Modeling

Background:

• Exoskeletons are increasingly used in homes and workplaces for tasks like remote operation and load assistance.
• Designing exoskeletons presents challenges due to the need to meet both robotic and ergonomic requirements, including user-specific anthropometry and mobility.
• Traditional exoskeleton design involves numerous physical prototypes and individual fitting, which is time-consuming and resource-intensive.

Purpose of the Study:

• To validate the design of a hand exoskeleton in a digital environment, eliminating the need for physical prototypes.
• To investigate whether a specific hand exoskeleton design alters users' finger kinematics during industrial tasks.

Main Methods:

• Development of user-specific musculoskeletal models based on motion capture data.
• Simulation of industrial tasks using these models to capture finger joint kinematics.
• Integration of the exoskeleton's kinematic chain into the musculoskeletal models to evaluate kinematic compliance.

Main Results:

• The digital validation approach demonstrated that the exoskeleton design did not significantly influence finger joint angles.
• High coefficient of determination (R² = 0.93) and low normalized root mean square error (nRMSE = 5.42°) indicate excellent agreement between models with and without the exoskeleton.
• The proposed exoskeleton design showed compliance with natural hand movements.

Conclusions:

• Digital validation of exoskeleton design using musculoskeletal and robotic modeling is a viable and promising approach.
• This method can significantly reduce the need for physical prototypes in the ergonomic assessment of exoskeletons and orthotic devices.
• The findings support the use of simulation-driven design for optimizing exoskeleton ergonomics prior to manufacturing.