TY - CONF

T1 - AMR-based mechanical pressure sensors

T2 - 15th International Symposium Magnetoresistive Sensors and Magnetic Systems

AU - Prediger, Maren S.

AU - Rechel, Mathias

AU - Wurz, Marc Christopher

PY - 2019/3

Y1 - 2019/3

N2 - This paper investigates a novel approach to measure mechanical pressure using anisotropic magneto-resistive sensors in combination with a matrix of magnetized hard magnetic particles. Ideally, with a deformation of the matrix due to an applied external pressure, the sensors will yield a measurable change in resistance. A demonstrator system consisting of AMR sensors on a glass substrate and hard magnetic particles embedded in PDMS was developed and subsequently evaluated. Proof of concept experiments focus on the characterization of the interaction between the particle matrix and the sensor(s) and measuring the sensor(s) response to repeatedly applied forces. With a thickness of 540 µm and filling degree of 33 %, the matrix emits a magnetic field of 3.5 kA/m. Proportional to the applied force, the AMR sensors display a parabolic decrease in resistivity upon matrix deformation. Exerted force and change in resistivity relate in a linear fashion, but hysteresis is observed for loading and unloading. Additionally, an array of AMR sensors can resolve spatial deformation distribution. With adequate optimization and miniaturization, this system appears promising for an application in soft robotics, prosthetics, or implant safety.

AB - This paper investigates a novel approach to measure mechanical pressure using anisotropic magneto-resistive sensors in combination with a matrix of magnetized hard magnetic particles. Ideally, with a deformation of the matrix due to an applied external pressure, the sensors will yield a measurable change in resistance. A demonstrator system consisting of AMR sensors on a glass substrate and hard magnetic particles embedded in PDMS was developed and subsequently evaluated. Proof of concept experiments focus on the characterization of the interaction between the particle matrix and the sensor(s) and measuring the sensor(s) response to repeatedly applied forces. With a thickness of 540 µm and filling degree of 33 %, the matrix emits a magnetic field of 3.5 kA/m. Proportional to the applied force, the AMR sensors display a parabolic decrease in resistivity upon matrix deformation. Exerted force and change in resistivity relate in a linear fashion, but hysteresis is observed for loading and unloading. Additionally, an array of AMR sensors can resolve spatial deformation distribution. With adequate optimization and miniaturization, this system appears promising for an application in soft robotics, prosthetics, or implant safety.

M3 - Paper

Y2 - 19 March 2019 through 20 March 2019

ER -