A system for pressure measurement within a surgical system is disclosed. The system comprises a pressure sensitive disc in communication with at least one applied pressure a magnetic field generator for generating at least one first magnetic field, and at least one sensor for measuring at least one second magnetic field, wherein the at least one first magnetic field at least partially creates the at least second magnetic field; and wherein the at least one sensor produces signal indicative of the distance between the at least one sensor and the at least one second magnetic field.

The present disclosure enables measurement with satisfactory sensitivity in a low pressure range, and thus accurate measurement in a wider pressure range, by providing a pressure sensor that includes a diaphragm layer and a pressure receiving region formed in the diaphragm layer. In addition, the pressure sensor includes a first piezostrictive element, a second piezostrictive element, a third piezostrictive element, and a fourth piezostrictive element. In addition, the pressure sensor includes a first magnetostrictive element, a second magnetostrictive element, a third magnetostrictive element, and a fourth magnetostrictive element.

The invention provides a pressure sensor (10) that can be produced at low cost, operates more accurately and resists to high burst pressures. The pressure sensor (10) comprises at least one membrane (12) and a magneto-elastic detection device (14) for magneto-elastically detecting mechanical stress caused by pressurization.

The invention provides a pressure sensor (10) that can be produced at low cost, operates more accurately and resists to high burst pressures. The pressure sensor (10) comprises at least one membrane (12) and a magneto-elastic detection device (14) for magneto-elastically detecting mechanical stress caused by pressurization.

According to one embodiment, a strain sensing element includes a film unit being deformable, a first and a second magnetic unit, and a strain sensor. The first magnetic unit is provided on the film unit and is arranged with the film unit in a first direction. The first magnetic unit includes a first magnetic body layer and a first intermediate magnetic layer. The second magnetic unit is provided on the film unit and is arranged with the first magnetic unit in a second direction crossing the first direction. The second magnetic unit includes a second magnetic body layer and a second intermediate magnetic layer. The strain sensor is provided on the film unit between the first magnetic unit and the second magnetic unit. An electrical characteristic of the strain sensor changes according to a deformation of the film unit.

According to one embodiment, a strain sensing element includes a film unit being deformable, a first and a second magnetic unit, and a strain sensor. The first magnetic unit is provided on the film unit and is arranged with the film unit in a first direction. The first magnetic unit includes a first magnetic body layer and a first intermediate magnetic layer. The second magnetic unit is provided on the film unit and is arranged with the first magnetic unit in a second direction crossing the first direction. The second magnetic unit includes a second magnetic body layer and a second intermediate magnetic layer. The strain sensor is provided on the film unit between the first magnetic unit and the second magnetic unit. An electrical characteristic of the strain sensor changes according to a deformation of the film unit.

A sub-micrometer pressure sensor is provided that includes a multilayered magnetic tunnel junction (MTJ) pillar that contains a non-magnetic metallic spacer separating a first magnetic free layer from a second magnetic free layer. The presence of the non-magnetic metallic spacer in the multilayered MTJ pillar improves the sensitivity without compromising area, and makes the pressure sensor binary (either on or off) with little or no drift, and sensitivity change over time. Moreover, the resistivity switch in such a pressure sensor is instantly and a low error rate is observed.

A sub-micrometer pressure sensor is provided that includes a multilayered magnetic tunnel junction (MTJ) pillar that contains a non-magnetic metallic spacer separating a first magnetic free layer from a second magnetic free layer. The presence of the non-magnetic metallic spacer in the multilayered MTJ pillar improves the sensitivity without compromising area, and makes the pressure sensor binary (either on or off) with little or no drift, and sensitivity change over time. Moreover, the resistivity switch in such a pressure sensor is instantly and a low error rate is observed.

To improve the output signal quality of a load measurement by means of active magnetization, the invention provides a load measurement method for measuring a mechanical load on a test object (14), comprising:

a) generating and applying a magnetic field to the test object (14);
b) detecting a magnetic field changed by the test object (14) as a result of a mechanical load on the test object (14) by means of a first magnetic field detection device (20) to generate a first measurement signal (U1, UAB),
c) detecting a magnetic field changed by the test object (14) as a result of a mechanical load on the test object (14) by means of a second magnetic field detection device (22) to generate a second measurement signal (U1, UAB),
d) computationally determining a third measurement signal (UBT) from the first measurement signal (U1, UAB) and the second measurement signal (U2, UAT), and preferably comprising the steps of
e) forming a difference from one (U2, UAT) of the first and the second measurement signals and the computationally determined third measurement signal (UBT) to produce an output signal,
f) determining the mechanical load applied to the test object (14) based on the output signal.

The invention also provides a corresponding load measurement device for carrying out the load measurement method.

A pressure sensor is provided with a cylindrical body made of a magnetostrictive material and configured to be deformed under a pressure of a fluid flowing inside and a detection portion configured to detect a change in magnetic field caused by distortion of the cylindrical body. The cylindrical body is provided with a peripheral wall portion curved or bent in an axial direction of the cylindrical body.