Device for detecting the position and orientation of a highly resistive magnetic material.

Abstract

This invention provides a device for measuring the position and orientation of an object to be measured using a magnetic sensor, by attaching a highly resistive magnetic material, such as an amorphous magnetic wire, to the object. [Solution] A magnetic wire is attached to the measurement band, saturated with magnetization using an external 3D high-frequency excitation coil, and a magnetic sensor located about 10 cm away detects only the excitation frequency signal without being affected by the external magnetic field. The saturated magnetization M is then measured, and the position and orientation of the measurement band can be determined by a computing device.

Description

[Technical Field]

[0001] The present invention relates to a device for measuring the position and orientation of an object to be measured using a magnetic sensor, by attaching a highly resistive magnetic material, such as an amorphous magnetic wire, to the object to be measured. [Background technology]

[0002] Systems for measuring the position and orientation of minute magnetic bodies are widely used. The principle of a system for measuring the position and orientation of a permanent magnet is that the magnetic field H emitted by the magnetization M of a magnetic body is expressed in a two-dimensional plane determined by the magnetization M vector and the distance R vector, as the magnetic field Hr in the direction of distance R and the magnetic field Hθ in the direction perpendicular to that direction. Hr = 2M / 4πμ0R 3 Hθ = M / 4πμ0R 3 Therefore, by measuring Hr and Hθ with a magnetic sensor at position R, the positional relationship between the magnetic material and the sensor can be determined in a coordinate system with the magnetic sensor's position as the origin.

[0003] A method for determining the position and orientation of a magnetic material is disclosed in Patent Document 1. A three-dimensional magnetic sensor grid ij is used as the magnetic sensor, and the virtual position and orientation of the magnetic material are defined as X, Y, Z, θ, and Φ. The difference eij between the theoretical magnetic field value Ht(ij) and the measured magnetic field value Hm(ij) is calculated using the magnetic sensor grid, and the error function E = Σeij is obtained. 2 This method uses the Gauss-Newton method to calculate the optimal X, Y, Z, θ, and Φ.

[0004] In particular, when detecting the position and orientation of a permanent magnet in a living organism, the magnet must be small, and the magnetic sensor must be placed at a distance of 4 cm or more. Patent Document 1 clearly shows the relationship between the magnetic moment at a distance of 4 cm, the detection performance of the magnetic sensor, and the positional accuracy and orientation accuracy. According to this study, a tenfold increase in magnetic moment strength improves accuracy and compass precision by a tenfold. Doubling the distance reduces the improvement to 1 / 8. For example, if the magnetic moment of a magnetic material is 5 nWbm (50 × 10⁻¹⁰ -10In the case of Wbm, at a distance of 10 cm, the magnetic field strength is small, at the level of 10 μT. However, it can be detected by a highly sensitive magnetic sensor with a detection force of 1 nT. When detected by a magnetic sensor grid and the signal is calculated using the Gauss-Newton method, the positional and azimuth accuracy can be calculated to be approximately ±1 mm and ±1 degree, respectively.

[0005] However, methods using permanent magnets have the drawback of being susceptible to external magnetic fields. For example, treatment rooms contain various medical diagnostic devices that emit magnetic fields, and the movement of these devices can affect the permanent magnet system. Therefore, there is a need to develop devices that are less susceptible to external magnetic fields.

[0006] The magnetization curve of amorphous magnetic wire in the high-frequency range is disclosed in Patent Document 2. It is shown that the relative permeability is about 2000, it saturates at a magnetization of about 800 A / m, and has a saturation magnetization of about 1.3 T.

[0007] A method has been proposed (Non-Patent Literature 1) that utilizes the high-frequency permeability characteristics of this magnetic wire to create an amorphous magnetic wire, which is then subjected to a small external high-frequency magnetic field to cause the magnetization to oscillate, and detected by an external magnetic sensor. The detection principle of this method is that when a small oscillating magnetic field is generated at a frequency of about 10 kHz using an excitation coil, the magnetization of the magnetic wire is generated with B = μH, and if μ is 10,000, the magnetic wire oscillates with a large magnetic moment M = B * SL (where SL is the volume of the wire). The magnetic sensor simultaneously measures the magnetic field of the excitation coil and the magnetic field of the magnetic wire, but by pre-measuring the value of the magnetic field created by the excitation coil and removing it from the measurement signal, the oscillating magnetic field H caused by the magnetic moment created by the amorphous magnetic wire can be measured separately.

[0008] The currently developed method involves fixing the positions of the magnetic wire, excitation coil, and magnetic sensor. Alternatively, the position of the magnetic wire or magnetic sensor changes along a specific direction, and the distance is determined. A technique has not yet been developed to fix the position of a sensor, measure the magnetic field H emitted by a magnetic material attached to a moving object, and determine the position and orientation of a magnetic wire at any position and orientation. The signal magnetic field H measured by the magnetic sensor is affected by the distance R1 and orientation d1 between the excitation power supply and the magnetic material, and also by the distance R2 and orientation d2 between the magnetic material and the magnetic sensor, so it is considered difficult to calculate the position and orientation of the magnetic material from H.

[0009] While systems for measuring the position and orientation of minute magnetic materials can now accurately measure at distances of approximately 5-10 cm due to improvements in magnetic sensor performance, they are still susceptible to the influence of the surrounding magnetic field environment. To address this issue, methods such as using magnetization via high-frequency excitation power supplies have been explored, but without success. In systems for measuring the position and orientation of magnetic materials, there is a need to devise measurement methods that replace permanent magnets with vibrating magnets, thereby measuring only specific vibrating magnetic fields. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] Patent No. 7126645 [Patent Document 2] Patent No. 6606698 [Non-patent literature]

[0011] [Non-Patent Document 1] Sensing System RV magnetic HP [Overview of the project] [Problems that the invention aims to solve]

[0012] According to Patent Document 1, the magnetic field H generated by the magnetization M of a high specific resistance magnetic material such as a magnetic wire depends on the magnetization M, the distance Rms between the magnetization M and the magnetic sensor, and the orientation relationship Dms. If the magnetization M is constant, Rms and Dms can be calculated by measuring the magnetic field H. However, when a magnetic material is excited by an external high-frequency power source, the magnetization M of the magnetic material is in a proportional relationship M=μH(t) with the intensity H(t) of the magnetic field generated by the power source. Since the magnetic field H depends on the distance Rcm and orientation relationship Dcm between the two, the magnetization M does not become constant depending on the distance R and orientation D. Even if the magnetic field Hms(t) generated by the magnetization M(t) is measured, the distance Rms and orientation Dms cannot be obtained from the measured values. The first object of the present invention is to vibrate the magnetization M at a constant magnetization intensity Ms and a constant frequency, that is, to make M=Mssin(2πft).

[0013] The second object is to eliminate the interference between the magnetic field Hc(t) generated by the excitation power source and the magnetic field Hm(t) generated by the magnetization M(t), and separate and detect only the magnetic field Hm(t).

[0014] The third object is to devise an electronic circuit and a measurement system that accurately measure the oscillating magnetic field Hm(t), and calculate and obtain the position and orientation of the magnetic wire from the measured values.

[0015] The fourth object is to find the material, shape and size of the high specific resistance magnetic material, the optimal performance and combination of the magnetic sensor and the excitation power source, and improve the measurement performance. Means for Solving the Problems

[0016] In the prior art, as shown in FIG. 1, attention is focused on the straight line a of the high-frequency magnetization curve of a magnetic wire, a large magnetization M is generated with a very small magnetic field, and the magnetic field generated by the magnetization is measured. However, since the magnetization M depends on the distance and orientation between the excitation coil and the wire, stable magnetization cannot be obtained. Accordingly, the inventors of the present invention focused on the saturation magnetic characteristics represented by straight line b, and conceived that a stable saturated magnetization M can be obtained by applying a sufficient excitation magnetic field of 800 A / m (10 G) or more. The problem is that since the magnetic wires are oriented in arbitrary directions, it is necessary to generate a magnetic field equal to or greater than the saturation magnetization in all directions from the excitation coil.

[0017] As the high-frequency excitation coil, a three-axis coil is used which combines an X-axis coil that generates magnetization Mx in the X-axis direction, a Y-axis coil that generates magnetization My in the Y-axis direction, and a Z-axis coil that generates magnetization Mz in the Z-axis direction. When Mx=Mcos(wt) and My=Msin(wt), the magnetization Mxy draws a circular orbit on the XY plane (Fig. 2A; 21), generates a magnetic field H in all directions, and can saturation-magnetize a magnetic wire oriented in any direction on the XY plane.

[0018] When Mx=Mcos(wt) and My=Msin(wt+90°), that is, when a phase difference of 90 degrees is provided to My with respect to Mx, Mxy draws a linear orbit on the XY plane (Fig. 2A; 22), and cannot magnetize a magnetic wire having an orientation perpendicular to the orbit. That is, it is necessary to select an appropriate phase difference so that a large magnetic field is generated in an arbitrary direction.

[0019] When Mx=Mcos(wt) and My=Msin(wt+30°), that is, when a phase difference of 30 degrees is provided to My, Mxy draws an elliptical orbit as shown in Fig. 2B; 23. By configuring the coil to generate a magnetic field capable of saturating the magnetic wire with the magnetization intensity in the minor axis direction, a magnetic wire oriented in any direction on the XY plane can be saturation-magnetized.

[0020] As shown in Fig. 2B; 24, when the phase angle Φ is set to -30 degrees, the ellipse tilts in the opposite direction, but a magnetic wire oriented in any direction on the XY plane can still be saturation-magnetized.

[0021] As shown in Fig. 2B; 25, when the phase angle Φ is set to 60 degrees, the minor axis becomes shorter, and a larger excitation coil is required to generate a magnetic field of 100 mT or more in the minor axis direction.

[0022] In the case of a high-frequency excitation three-axis coil, if Mx = Mcos(wt), My = Mcos(wt+30°), and Mz = Mcos(wt-30°), then Mxy on the XY plane becomes an ellipse as shown in Figure 3;31, and it is possible to saturate magnetize a wire in any orientation on the XY plane.

[0023] The Myz on the YZ plane is as shown in Figure 3;32, and it is possible to saturate magnetize a magnetic wire in any orientation on the YZ plane.

[0024] As shown in Figure 3;33, Mzx on the ZX plane can saturate magnetize magnetic wires in any orientation on the ZX plane.

[0025] In three-dimensional space, projecting a magnetic wire oriented in any direction onto the XY, YZ, and ZX planes results in straight lines on each plane. Since magnetic wires in any direction on each plane can be saturated, it becomes possible to saturate a magnetic wire oriented in any direction in three-dimensional space.

[0026] The magnitude of magnetization M is given by the absolute value |M| = √(Mx 2 +My 2 Since ) = M√(1+sinΦ / 2), the minor axis of the ellipse in Figure 2A;22 with a phase angle Φ=30 degrees is 0.86M and the major axis is 1.14M. In Figure 2B;34, with a phase angle of Φ=60 degrees, the minor axis of the ellipse is 0.78M and the major axis is 1.22M. In other words, the absolute value |M| will oscillate within that range. The magnitude M of the magnetization of the excitation coil is a minimum of 0.78M, so that the magnetic field it creates at the position of the magnetic wire is 10G. It is preferable to make the phase difference as close as possible and reduce the difference in magnitude between the short axis and the long axis.

[0027] The magnetization of a magnetic wire corresponds to a sinusoidal oscillating magnetic field H, and saturates when the magnetic field H exceeds 10G, thus exhibiting trapezoidal magnetization behavior as shown in Figure 4. An important point here is that the maximum value of the magnetization M is constant, resulting in a saturation magnetization Mws.

[0028] A magnetic sensor simultaneously measures the magnetic field Hc(t) emitted by the excitation power supply and the magnetic field Hm(t) emitted by the magnetization M(t). Since the positions of the excitation power supply and the magnetic sensor are fixed, the magnetic field Hc(t) emitted by the excitation power supply can be measured without the magnetic wire, and by subtracting this value from the actual measured value, only the magnetic field Hm(t) emitted by the magnetization M(t) can be determined.

[0029] However, the measurement range and magnetic field detection power of a magnetic sensor are inversely related. If the detection power of the magnetic sensor is increased to measure the minute magnetic field created by the magnetization of the magnetic wire, the measurement range narrows, and the value of Hc + Hm exceeds the measurement range, making measurement impossible. Conversely, if the measurement range is widened, the detection power decreases, making it impossible to measure the minute magnetic field created by the magnetization of the magnetic wire. To solve this problem, the excitation coil and magnetic sensor were positioned opposite each other with the magnetic wire in between. This arrangement allows the excitation coil to create a large magnetic field at the location of the magnetic wire, but the magnetic field becomes smaller at the location of the magnetic sensor, which is further away, thus narrowing the measurement range of the magnetic sensor. By narrowing the measurement range, the magnetic sensor can maintain excellent detection power and detect the small magnetic field created by the saturation magnetic field M of the magnetic wire.

[0030] In summary, the second challenge was overcome by subtracting the known magnetic field Hc(t) emitted by the excitation power supply from the measured magnetic field H, thereby determining only the magnetic field Hm(t) emitted by the magnetization M(t). Furthermore, the conflict between the measurement range of the magnetic sensor and the magnetic field detection force was overcome by arranging the magnetic wire, magnetic sensor, and excitation coil in a counter-arrangement configuration, and by optimizing the measurement range and detection force of the magnetic sensor.

[0031] For the third task, which involved devising an electronic circuit and measurement system to accurately measure the oscillating magnetic field Hm(t) and calculating the position and orientation of the magnetic wire from the measured values, the excitation coil frequency and the measurable frequency of the magnetic sensor were changed from 100 Hz to 100 kHz, and the saturation magnetization M of the magnetic wire was determined from the maximum measured value of the magnetic sensor. As a magnetic sensor, we utilized the circuit of a GSR sensor that is excited with GHz pulses, reduced the capacitor capacitance of the detection circuit to enable high-speed detection, and devised a circuit that uses a noise filter and a lock-in amplifier to detect only specific frequency signals with high precision. As a result, we succeeded in improving the GSR sensor to a high-frequency compatible sensor with a wide measurement range and high detection power. Since the magnetic field emitted by magnetization M is related to the distance R(X, Y, Z) between the magnetic wire and the magnetic sensor and the orientation (θ, Φ), we decided to calculate the position and orientation using the Gauss-Newton method disclosed in Patent Document 1.

[0032] For the fourth challenge, as high-resistivity magnetic materials, amorphous magnetic materials, magnetic nanocrystalline materials, electromagnetic stainless steel, and magnetic ferrites with resistivity of 80 μΩcm or more can be used. In terms of shape, wire, thin strip, or pipe shape can be considered depending on the object being measured. By increasing the cross-sectional area and making the permeance coefficient 1.0 or higher when saturated magnetized, the magnetic material will have a large magnetization moment and can generate a large external magnetic field.

[0033] Regarding magnetic sensors, a three-dimensional magnetic sensor grid can be used, and measurement accuracy can be improved by maximizing the grid area and narrowing the spacing between grid elements. A magnetic sensor grid is disclosed in Patent Document 1.

[0034] The output of the excitation power supply needs to be a large magnetic field to saturate the magnetic material, but if the magnetic field exceeds the saturation range of the magnetic sensor, measurement becomes impossible. In other words, it is preferable that the strength of the excitation magnetic field is about the same as or less than the strength of the measurement magnetic field. As described above, it is important to find the optimal combination of high-resistivity magnetic material, magnetic sensor grid and magnetic sensor performance, and excitation power supply strength and frequency to improve measurement performance.

[0035] As described above, the four problems of the present invention have been solved, and the present invention, namely an apparatus for detecting the position and orientation of an amorphous magnetic wire, comprising an amorphous magnetic wire, a high-frequency excitation coil, a magnetic sensor, a magnetic sensor signal processing circuit, and a position and orientation calculation device, has been invented. The amorphous magnetic wire is attached to an object to be measured, the high-frequency excitation coil and magnetic sensor are arranged in the opposite direction (left-right or up-down direction) to the amorphous magnetic wire, the high-frequency excitation coil generates a sufficiently large magnetic field with a frequency of 100 Hz or more to cause the amorphous magnetic wire to vibrate and saturate magnetize, the strength of the magnetic field emitted by the vibrating and saturating magnetization is detected by a magnetic sensor placed in the opposite direction, the detected magnetic signal is converted into an electrical signal by a signal processing circuit, and the position and orientation of the amorphous magnetic wire is detected by the position and orientation calculation device.

[0036] A preferred invention involves using a wire or pipe-shaped amorphous material as the high-resistivity magnetic material, a three-dimensional high-frequency excitation coil as the high-frequency excitation coil, and a three-dimensional magnetic sensor grid as the magnetic sensor. [Effects of the Invention]

[0037] This invention allows a highly resistive magnetic material, such as an amorphous magnetic wire, to be attached to an object to be measured, and its position and orientation can be measured by a magnetic sensor located at a distance, without being affected by external magnetic field environmental noise. This is useful for robotic treatments such as catheter treatment. [Brief explanation of the drawing]

[0038] [Figure 1] This figure shows the high-frequency magnetization curve of a magnetic wire, with line a representing the dependence on the magnetic field strength emitted by the excitation coil and line b representing the saturation magnetic properties. [Figure 2A] This figure shows the trajectory of magnetization Mxy in the XY plane for a combination of high-frequency excitation coils in a two-axis coil system. [Figure 2B] This figure shows the elliptical orbit of the magnetization Mxy in the XY plane for a combination of high-frequency excitation coils in a two-axis coil system. [Figure 3]Mxy on the XY plane, Myz on the YZ plane and Mzx on the ZX plane of the excitation high-frequency 3-axis coil are diagrams showing the saturation magnetization of a magnetic wire in any orientation. [Figure 4] It is a diagram showing trapezoidal magnetization fluctuation of a magnetic wire in a magnetic field H oscillating as a sine function. [Figure 5] It is a conceptual diagram of an apparatus for detecting the position and orientation of a high specific resistance magnetic material.

Best Mode for Carrying Out the Invention

[0039] In the best embodiment of the present invention, the arrangement relationship of an amorphous magnetic wire or pipe, a high-frequency excitation coil and a magnetic sensor grid is shown in Figure 5. The amorphous magnetic wire has a diameter of 200 μm or less and a length of 20 mm or less. The magnetic properties are a specific resistance of 90 μΩcm to 150 μΩcm, a saturation magnetization of 0.8 T to 1.6 T, a magnetic permeability of 1000 to 20000, and a magnetic moment of 10×10 -10 Wbm or less, preferably 2×10 ―13 to 2×10 -11 Wbm. It generates a magnetic field of 5 nT (0.05 mG) to 500 nT (5 mG) at a position 10 cm away.

[0040] In the case of an amorphous magnetic pipe, the diameter is 3 mm or less, the thickness is 0.2 mm or less, and the length is 20 mm or less. The saturation magnetization is 0.8 T to 1.6 T, and the magnetic moment is 1×10 -8 Wbm or less, preferably 2×10 ―9 Wbm. It can generate a magnetic field of 90 μT or less at a position 10 cm away, and a magnetic field of 1.5 μT or less at a position 40 cm away. It should be noted that, as the high specific resistance magnetic material, in addition to the above-mentioned shapes, a thin plate shape may also be used.

[0041] For the high-frequency excitation coil, a frequency of 100 Hz or more and 500 kHz or less is used. It is a 3-axis coil, and the magnetic moment is preferably 3.2×10 -10 Wbm or less, and 3.2×10 -11It is above Wbm. It can generate a magnetic field of 16G (1280A / m) or less at a distance of 10cm and a magnetic field of 2G (160A / m) or less at a distance of 20cm.

[0042] The magnetic sensor is positioned 10cm to 30cm away from the high-frequency excitation coil. The magnetic wire is fixed to the object being measured and moves with the object. The relative position of the magnetic wire to the magnetic sensor is 2cm to 15cm away, and the range of movement is the size of the sensor grid, ranging from 10cm square to 30cm square. A GSR sensor was used as the magnetic sensor. Its performance was such that the measurement range was 1G to 20G, and the magnetic field detection force at frequencies above 100Hz was 5pT to 100pT.

[0043] The position and orientation calculation device uses a 3D magnetic sensor grid, with a grid area of ​​100 cm². 2 ~900cm 2 The number of sensors ranges from 25 to 900. The resulting amorphous magnetic wire exhibits positional and orientation accuracy of 1 mm or less and azimuth accuracy of 2° or less. [Examples]

[0044] [Example 1] Figure 5 shows the arrangement of the amorphous magnetic wire, high-frequency excitation coil, and magnetic sensor grid in Embodiment 1 of the present invention. The amorphous magnetic wire has a diameter of 10 μm, a length of 5 mm, a saturation magnetization of 1.0 T, and a magnetic moment of 3.2 × 10⁻⁶. -13 It is a Wbm device. At a distance of 10 cm, it generates a magnetic field of 10 mG. At a distance of 2.5 cm, it creates a magnetic field of 640 mG.

[0045] A high-frequency excitation coil with a frequency of 100 kHz was used. The magnetic moment of the three-axis coil was 3.1 × 10⁻⁶. -10 It is in Wbm. It generates a magnetic field of 10G (800A / m) at a distance of 10cm and a magnetic field of 1.2G (96A / m) at a distance of 20cm.

[0046] The magnetic sensor is positioned 20 cm away from the high-frequency excitation coil. The magnetic wire is fixed to the object being measured and moves with the object. The relative position of the magnetic wire to the magnetic sensor is 10 cm away, and the range of movement is limited to a 20 cm square area, which is the width of the sensor grid. A GSR sensor was used as the magnetic sensor. Its performance was such that the measurement range was ±4G and the magnetic field detection force at frequencies above 100Hz was 50pT. Here, a GSR sensor refers to an ultra-high-sensitivity micro-magnetic sensor based on the high-speed spin rotation effect caused by pulsed currents with a frequency of GHz.

[0047] The position and orientation calculation device uses a 3D magnetic sensor grid, with the grid being a square with sides of 200 mm. Each 3D element is a 10 mm square, and there are 20 x 20 = 400 sensors. The resulting positional and orientation accuracy of the amorphous magnetic wire is 0.5 mm or less for positional accuracy and 1° or less for orientation accuracy.

[0048] [Example 2] Embodiment 2 of the present invention is obtained by replacing the amorphous magnetic wire of Embodiment 1 with an amorphous magnetic pipe. The amorphous magnetic pipe has a diameter of 1 mm, a thickness of 20 μm, and a length of 10 mm, with a saturation magnetization of 1.0 T and a magnetic moment of 32000 × 10⁻¹⁴. -13 It is a Wbm (Weight of Blast) device. It generates a magnetic field of 30 μT at a distance of 10 cm. At a distance of 40 cm, it creates a magnetic field of 450 nT. The distance between the object being measured and the magnetic sensor can be set to approximately 40 cm. [Industrial applicability]

[0049] This invention relates to a device for measuring the position and orientation of an object to be measured by attaching a highly resistive magnetic material, such as an amorphous magnetic wire, to the object, and using a magnetic sensor. It can accurately measure only the magnetic field emitted by the magnetic wire, without being affected by the surrounding magnetic field. This invention is useful for robotic treatment or remote control of medical devices within the body. [Explanation of Symbols]

[0050] 1: High-frequency magnetization curve of magnetic wire 11: Excitation coil 12: Line b of the saturation magnetic properties 21: Circular orbit of magnetization Mxy in the XY plane 22: In the XY plane, when My is 90 degrees in phase with respect to Mx, the magnetization Mxy is in a linear trajectory. 23: In the XY plane, when My is 30 degrees in phase with respect to Mx, the magnetization Mxy is in an elliptical orbit. 24: In the XY plane, when My is in phase with respect to Mx by -30 degrees, the magnetization Mxy is in an elliptical orbit in opposite directions. 25: In the XY plane, when My is 60 degrees in phase with respect to Mx, the magnetization Mxy is in a short elliptical orbit along its minor axis. 31: In the XY plane of an excitation high-frequency three-axis coil, Mxy represents the saturation magnetization of a magnetic wire in any orientation. 32: In the YZ plane of an excitation high-frequency three-axis coil, Myz is the saturation magnetization of a magnetic wire in any orientation. 33: On the ZX plane of an excitation high-frequency three-axis coil, Mzx is the saturation magnetization of a magnetic wire in any orientation. 4: Magnetization of magnetic wires 41: Trapezoidal magnetization behavior 5: Device for detecting the position and orientation of high-resistivity magnetic materials 51: Amorphous magnetic wire (amorphous magnetic pipe) 52: High-frequency excitation coil (3-axis coil) 53: Magnetic Sensor Grid 54: Object to be measured 55: Fan-shaped excitation range

Claims

1. In a device for detecting the position and orientation of a high-resistivity magnetic material, comprising an object to be measured, a high-resistivity magnetic material, a high-frequency excitation coil, a magnetic sensor, a magnetic sensor signal processing circuit, and a position and orientation calculation device, The high-resistivity magnetic material is attached to a predetermined position on the object to be measured. The high-frequency excitation coil is arranged in the opposite direction (left-right or up-down) to the high-resistivity magnetic material, and generates a magnetic field with a frequency of 100 Hz or higher to cause the high-resistivity magnetic material to vibrate and saturate magnetize. The magnetic sensor simultaneously detects the strength of the magnetic field emitted by the high-frequency excitation coil and the strength of the magnetic field emitted by the oscillating saturation magnetization as electrical signals. The aforementioned electrical signal is converted into a magnetic signal by the magnetic sensor signal processing circuit and input as an input signal to the position and orientation calculation device. The position and orientation calculation device is characterized in that the strength of the magnetic field emitted by the high-frequency excitation coil when the high-resistivity magnetic material is not attached to the object to be measured is stored as a built-in signal, and the position and orientation of the high-resistivity magnetic material are detected by subtracting the built-in signal from the input signal and using the differential signal.

2. In claim 1, The aforementioned high-resistivity magnetic material can take the form of a wire, a thin plate, or a pipe. A device for detecting the position and orientation of a highly resistive magnetic material, characterized by having magnetic properties such as a resistivity of 90 μΩcm or more, a saturation magnetization of 0.8 T or more, a permeability of 1000 or more, and a permeance coefficient of 1.0 or more when saturated.

3. In claim 1, The aforementioned high-frequency excitation coil consists of a three-dimensional high-frequency excitation coil, and the device for detecting the position and orientation of a high-resistivity magnetic material is characterized by using an excitation frequency that has a phase difference between the three axis coils.

4. In claim 2, The magnetic sensor is characterized by comprising a three-dimensional magnetic sensor grid, and is a device for detecting the position and orientation of a high-resistivity magnetic material.

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