Mechanical Decoupling of a Multiaxial Force Sensor via Multiple Sensing Mechanisms

ABSTRACT Multiaxial force sensing plays a crucial role in robotics and human–robot interaction. However, many existing sensors suffer from mechanical coupling between normal and shear forces, making it difficult to distinguish force directions without complex calibration. Here, we propose a multiaxial force sensor that achieves mechanical decoupling through an innovative structural design combining multiple sensing principles. Normal force is detected via a porous piezoresistive layer, while shear forces and directions are captured through capacitive changes among five in‐plane electrodes. The decoupling capability and sensing performance were systematically validated through simulations and experiments. The sensor exhibits a normal force sensitivity of 1.27 × 10 ^{− 2} kPa ^{− 1} and shear force sensitivity exceeding 18.1 mN ^{− 1} . Directional shear sensing is realized by analyzing differential capacitance among electrodes. Notably, shear force detection remains stable under varying normal loads, confirming effective mechanical decoupling. These features make the proposed sensor a promising candidate for applications in robotic manipulation and human–machine interfaces.