Flexible wide-range multidimensional force sensors inspired by bones embedded in muscle.

Area of Science:

• Materials Science and Engineering
• Robotics and Intelligent Systems
• Biomedical Engineering

Background:

• Flexible sensors are crucial for motion monitoring, HMIs, personalized medicine, and soft robotics.
• Existing sensors face challenges like low output, limited range, and unidirectional detection.
• There is a need for flexible sensors with simultaneous high performance and wide-range multidimensional force detection.

Purpose of the Study:

• To develop a flexible wide-range multidimensional force sensor (FWMFS) with enhanced performance.
• To enable multidimensional force detection using an adjustable magnetic field.
• To achieve miniaturization and improved output sensitivity through multilayer stacked coils.

Main Methods:

• Designed a novel FWMFS mimicking bone-muscle structures with an adjustable magnetic field.
• Incorporated multilayer stacked coils to boost output voltage sensitivity.
• Tested normal force detection from 0.5 N to 60 N and lateral force detection from 0.2 N to 1.1 N.

Main Results:

• Achieved high voltage sensitivities for normal forces (0.227 mV/N and 0.047 mV/N) and lateral forces (1.039 mV/N and 0.194 mV/N).
• Demonstrated FWMFS capability in monitoring finger pressure, sliding trajectories, and plantar pressure for human movement assessment.
• Achieved 92% recognition accuracy for five human movements using k-nearest neighbors classification.

Conclusions:

• The developed FWMFS offers simultaneous flexibility and high performance for multidimensional force sensing.
• The sensor shows significant potential in intelligent sensing, personalized spatial recognition, and AI-driven biometric authentication.
• Future applications include advanced human-machine interfaces, personalized medicine, and enhanced robotic systems.