A Magnetoresistive Tactile Sensor for Harsh Environment Applications

Abstract

A magnetoresistive tactile sensor is reported, which is capable of working in high temperatures up to 140 °C. Hair-like bioinspired structures, known as cilia, made out of permanent magnetic nanocomposite material on top of spin-valve giant magnetoresistive (GMR) sensors are used for tactile sensing at high temperatures. The magnetic nanocomposite, consisting of iron nanowires incorporated into the polymer polydimethylsiloxane (PDMS), is very flexible, biocompatible, has high remanence, and is also resilient to antagonistic sensing ambient. When the cilia come in contact with a surface, they deflect in compliance with the surface topology. This yields a change of the GMR sensor signal, enabling the detection of extremely fine features. The spin-valve is covered with a passivation layer, which enables adequate performance in spite of harsh environmental conditions, as demonstrated in this paper for high temperature.

Crack-based and Hair-like Sensors Inspired from Arthropods: A Review

“…In addition to detecting strain, the HLS can also detect the texture of the surface to achieve tactile perception. Alfadhel et al developed a versatile biomimetic nanocomposite tactile sensor that detects shear and vertical forces, and can feel the texture of the contact surface [124,125] . This sensor detects shear and vertical forces, and the sensor can be used in air or water without any modification.…”

“…A hair rod structure having a small modulus of elasticity allows the sensor to avoid damage to the hair rod and the bottom elastic member due to excessive external force. In addition to this, the wool structure can exhibit softness, causing it to bend, and the sensor can complete the process of tactile perception [122,125] .…”

Tunable, Flexible Composite Magnets for Marine Monitoring Applications

“…In order to provide a more versatile solution for magnetic-based underwater monitoring systems, we propose the use of composite magnets. Mixing magnetic fillers into a soft and flexible carrier matrix has been recently proposed for a new generation of magnetic composite materials [8,21,22] and exploited in biomedical [23][24][25][26] , robotics [27][28][29][30][31] , and automotive [32][33][34] fields.…”

Cylindrical Magnetic Nanowires Applications

“…The PDMS structure protects the NWs from corrosion and provides higher mechanical flexibility, allowing more pronounced deflections. This allowed to fabricate force sensors for flow, acoustic, pressure or robotic applications [13], [14], [131]- [133] and energy harvesters [16], [17].…”