Event detection method, event detection system and program

Abstract

SOLUTION: To provide an event detection method that detects an event corresponding to a position of a magnetic field occurrence part by detecting magnetic fields of at least two axes generated by a predetermined magnetic field generation part, and includes a stage for acquiring an event generation part on the basis of a magnetic field detected by a magnetic sensor, a stage for selecting a detection axis for detecting an event on the basis of the event generation position, a stage for calculating a trigger threshold corresponding to the event generation position in a detection axis, and a stage for acquiring a trigger signal for showing that the magnetic field detected by the magnetic sensor and the trigger threshold satisfy a predetermined conditions.SELECTED DRAWING: Figure 1B

Description

[Technical Field]

[0001] The present invention relates to an event detection method, an event detection system, and a program. [Background technology]

[0002] Patent Document 1 states that "a position sensor capable of detecting the movement of a detection target with a single detection unit even if the amount of movement of the detection target becomes large is provided." Patent Document 2 states that "a position detection sensor having linear output over a long detection distance and capable of position detection with high detection accuracy is provided." [Prior art document] [Patent documents] Patent Document 1: JP 2019-2835 A Patent Document 2: Japanese Patent Application Laid-Open No. 2003-167627 Summary of the Invention

[0003] In a first aspect of the present invention, there is provided an event detection method for detecting an event corresponding to the position of a magnetic field generating unit by detecting magnetic fields of two or more axes generated by a predetermined magnetic field generating unit using a magnetic sensor, the event detection method comprising the steps of: acquiring an event occurrence position based on the magnetic field detected by the magnetic sensor; selecting a detection axis for event detection based on the event occurrence position; calculating a trigger threshold corresponding to the event occurrence position on the detection axis; and receiving a trigger signal indicating that the magnetic field detected by the magnetic sensor and the trigger threshold satisfy a predetermined condition.

[0004] In a second aspect of the present invention, an event detection system is provided, comprising a magnetic field generating unit that generates a predetermined magnetic field, a magnetic sensor for detecting the magnetic field generated by the magnetic field generating unit, and a processing unit that processes a signal detected by the magnetic sensor, wherein the processing unit has an acquisition unit that acquires the event occurrence position based on the magnetic field detected by the magnetic sensor, a selection unit that selects a detection axis for event detection based on the event occurrence position, and a calculation unit that calculates a trigger threshold on the detection axis according to the event occurrence position, and the magnetic sensor has an output unit that outputs a trigger signal indicating that the detected magnetic field and the trigger threshold satisfy a predetermined condition.

[0005] In a third aspect of the present invention, there is provided a program for causing a computer to execute the event detection method according to the first aspect of the present invention.

[0006] The above summary of the invention does not list all of the features of the present invention, and subcombinations of these features may also be inventions. [Brief explanation of the drawings]

[0007] [Figure 1A] 1 is a block diagram showing an overview of an event detection system 100. FIG. [Figure 1B] A more specific configuration of the magnetic sensor 20 and the processing unit 30 will be shown. [Figure 2A] An example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged will be shown. [Figure 2B] An example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged will be shown. [Figure 2C] An example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged will be shown. [Figure 3A] The magnetic field generating unit 10 is shown disposed at a reference position P0. [Figure 3B] The magnetic field generating unit 10 is shown disposed at the event occurrence position Pe. [Figure 3C] 1 shows the magnetic field waveform according to the position of the magnetic field generating unit 10. [Figure 3D]The changes in magnetic flux density and trigger signal corresponding to the magnetic field waveform of Figure 3C are shown. [Figure 4A] An example of a threshold determination method using a biaxial magnetic field is shown below. [Figure 4B] An example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged will be shown. [Figure 4C] An example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged will be shown. [Figure 4D] An example of a threshold determination method using a biaxial magnetic field is shown below. [Figure 5] 10 shows a comparative example of a threshold determination method using a uniaxial magnetic field. [Figure 6] A more specific example of the threshold determination method will be described below. [Figure 7A] A more specific example of the threshold determination method will be described below. [Figure 7B] A more specific example of the threshold determination method will be described below. [Figure 7C] A more specific example of the threshold determination method will be described below. [Figure 7D] A more specific example of the threshold determination method will be described below. [Figure 7E] A more specific example of the threshold determination method will be described below. [Figure 8A] A more specific example of the threshold determination method will be described below. [Figure 8B] A more specific example of the threshold determination method will be described below. [Figure 8C] A more specific example of the threshold determination method will be described below. [Figure 8D] A more specific example of the threshold determination method will be described below. [Figure 9] 1 shows an example of an operation flow of the event detection system 100. [Figure 10] 1 shows an example of the configuration of an event detection system 100. [Figure 11] 22 illustrates an example computer 2200 in which aspects of the present invention may be embodied, in whole or in part. DETAILED DESCRIPTION OF THE INVENTION

[0008] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0009] 1A is a block diagram showing an overview of an event detection system 100. The event detection system 100 includes a magnetic field generating unit 10, a magnetic sensor 20, and a processing unit 30.

[0010] The magnetic field generating unit 10 generates a predetermined magnetic field. For example, the magnetic field generating unit 10 includes a two-pole magnet consisting of a north pole and a south pole arranged in a predetermined direction. The magnetic field generating unit 10 generates a magnetic field with a predetermined magnetic waveform according to the magnetization direction of the magnet. The magnetic field generating unit 10 may move in a predetermined direction to change the magnetic field waveform.

[0011] The magnetic sensor 20 detects the magnetic field generated by the magnetic field generating unit 10. The magnetic sensor 20 detects magnetic fields on at least two or more detection axes. The magnetic sensor 20 in this example is a multi-axis magnetic sensor that can detect magnetic fields on two or more axes. However, the magnetic sensor 20 may also detect magnetic fields on two or more axes by having multiple single-axis sensors. The magnetic sensor 20 acquires measurement data that detects the magnetic flux density of magnetic fields on two or more axes. The magnetic sensor 20 generates a trigger signal when the acquired measurement data satisfies a predetermined condition. The trigger signal is an interrupt signal that notifies the magnetic sensor 20 of a change in state.

[0012] The processing unit 30 processes the signal detected by the magnetic sensor 20. The processing unit 30 serially communicates with the magnetic sensor 20 and receives measurement data from the magnetic sensor 20. The processing unit 30 also changes its internal state in response to a trigger signal from the magnetic sensor 20. For example, in response to receiving a trigger signal, the processing unit 30 changes the device in which the processing unit 30 is installed from a standby state to an activated state.

[0013] The event detection system 100 generates a trigger signal based on the detection of an event according to the relative positional relationship between the magnetic field generating unit 10 and the magnetic sensor 20. The event detection system 100 of this example generates a trigger signal in response to the magnetic field generating unit 10 moving to a predetermined position, and executes a predetermined operation.

[0014] In one example, the event detection system 100 is installed in a mobile terminal such as a smartphone (e.g., a rollable phone) with an expandable display, and outputs a trigger signal for switching the display when the display expands or contracts to a predetermined position. Furthermore, the event detection system 100 may switch the smartphone from a standby state to an active state when an event is detected. Furthermore, the event detection system 100 may transition the smartphone from the active state to the standby state when no operation is performed for a predetermined period of time.

[0015] 1B shows a more specific configuration of the magnetic sensor 20 and the processing unit 30. The magnetic sensor 20 of this example includes a detection unit 22 and an output unit 24. The processing unit 30 includes an acquisition unit 32, a selection unit 34, and a calculation unit 36.

[0016] The detection unit 22 detects the magnetic field generated by the magnetic field generation unit 10. The detection unit 22 outputs measurement data (Bx, By, Bz) of the detected magnetic field to the detection unit 22 or the processing unit 30. Bx, By, and Bz indicate the magnetic flux density in the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively. The detection unit 22 in this example detects the magnetic flux density in three axis directions as measurement data, but may also detect the magnetic flux density in two axis directions.

[0017] The acquiring unit 32 acquires measurement data (Bx, By, Bz) from the magnetic sensor 20. For example, the acquiring unit 32 acquires measurement data when the magnetic field generating unit 10 is located at a predetermined reference position P0. The reference position P0 may be any position at which the magnetic sensor 20 can detect the position of the magnetic field generating unit 10.

[0018] The acquisition unit 32 may also acquire information necessary for selecting a detection axis or calculating a trigger threshold, such as an event occurrence position Pe of the magnetic field generating unit 10. A method for acquiring the event occurrence position Pe will be described later. The acquisition unit 32 outputs the acquired event occurrence position Pe to the selection unit 34 and the calculation unit 36. The acquisition unit 32 may acquire information such as the event occurrence position Pe from a storage unit provided in the processing unit 30.

[0019] Furthermore, the acquisition unit 32 may acquire a detectable region and an undetectable region according to the position of the magnetic field generation unit 10 for each detection axis. A detectable region is a region in which the trigger threshold can be detected in the corresponding detection axis. An undetectable region is a region in which the trigger threshold cannot be detected in the corresponding detection axis. A case in which the trigger threshold cannot be detected occurs, for example, when the position of the magnetic field generation unit 10 cannot be identified from the output magnetic flux density. Multiple detection axes may be selected so that each has a detectable region and an undetectable region in a different region.

[0020] The selector 34 selects a detection axis for event detection based on the event occurrence position Pe. For example, the selector 34 selects, as the detection axis, a first axis parallel to a predetermined first direction in which the magnetic field generating unit 10 moves, or a second axis perpendicular to the first axis. The selector 34 selects the detection axis so that the position of the magnetic field generating unit 10 falls within the detectable region. A specific method for selecting the detection axis will be described later.

[0021] The calculation unit 36 ​​calculates a trigger threshold value corresponding to the event occurrence position Pe on the detection axis. The trigger threshold value is the magnetic flux density detected by the magnetic sensor 20 at the event occurrence position Pe on the selected detection axis. The calculation unit 36 ​​outputs the calculated trigger threshold value to the output unit 24.

[0022] The output unit 24 detects a predetermined trigger threshold and outputs a trigger signal. In this example, the output unit 24 generates a trigger signal when the magnetic flux density of the magnetic field detected by the detection unit 22 exceeds or falls below the trigger threshold. The output unit 24 outputs the generated trigger signal to the processing unit 30. The processing unit 30 may execute a predetermined process in response to receiving the trigger signal.

[0023] 2A shows an example of a method for arranging the magnetic field generating unit 10 and the magnetic sensor 20. This figure shows the magnetic field generating unit 10 and the magnetic sensor 20 from the viewpoint of the Y-axis direction.

[0024] The magnetic field generating unit 10 in this example has a north pole and a south pole arranged in the X-axis direction. The X-axis direction is an example of a first direction. However, the magnetic field generating unit 10 may move not only in the X-axis direction but also in the Y-axis direction, Z-axis direction, or other directions. The magnetic field generating unit 10 in this example has a south pole on the negative side of the north pole in the X-axis direction, but is not limited to this. The distance between the magnetic field generating unit 10 and the magnetic sensor 20 in the Z-axis direction is not particularly limited as long as the magnetic sensor 20 can detect the magnetic field of the magnetic field generating unit 10.

[0025] In this example, the shape of the magnet of the magnetic field generating unit 10 is a rectangular parallelepiped, but it may be another shape, such as a cylinder. The material of the magnet may be any material, such as neodymium or ferrite. In one example, when the event detection system 100 is mounted on a rollable phone, the magnetic field generating unit 10 is mounted on the display side and the magnetic sensor 20 is mounted on the housing side, and the relative positions of the magnetic field generating unit 10 and the magnetic sensor 20 change according to the expansion and contraction of the display.

[0026] Note that, if the relative positional relationship between the magnetic field generating unit 10 and the magnetic sensor 20 changes, the magnetic sensor 20 may move, or both the magnetic field generating unit 10 and the magnetic sensor 20 may move. In one example, when the event detection system 100 is mounted on a rollable phone, the magnetic field generating unit 10 is mounted on the display side and the magnetic sensor 20 is mounted on the housing side, and the relative positional relationship between the magnetic field generating unit 10 and the magnetic sensor 20 changes according to the expansion and contraction of the display.

[0027] 2B shows an example of how to arrange the magnetic field generating unit 10 and the magnetic sensor 20. This figure shows the magnetic field generating unit 10 and the magnetic sensor 20 from the viewpoint of the Z-axis direction. That is, the viewpoint in this example is rotated 90 degrees from that in FIG. 2A.

[0028] The magnetic field generating unit 10 moves across the magnetic sensor 20 in the XY plane. The magnetic field generating unit 10 crossing the magnetic sensor 20 means that the magnetic field generating unit 10 and the magnetic sensor 20 partially overlap in the XY plane. In other words, the magnetic field generating unit 10 may move so as to pass over the magnetic sensor 20. The magnetic field generating unit 10 may also move across the magnetic sensor 20 in the YZ plane. When the magnetic field generating unit 10 crosses the magnetic sensor 20 in a predetermined plane, it becomes easier to detect changes in magnetic flux density according to the movement of the magnetic field generating unit 10, and it becomes easier to determine the trigger threshold.

[0029] Furthermore, although the magnetic field generating unit 10 in this example moves parallel to the X-axis direction, it may also move obliquely to the X-axis in the XY plane. In this way, the magnetic field generating unit 10 is not limited to being arranged across the magnetic sensor 20 in the XY plane, and the degree of freedom in housing design can be increased.

[0030] In this example, the magnetic field generating unit 10 moves in a straight line, but this is not limiting. That is, the magnetic field generating unit 10 may move in a curved line or along any other arbitrary trajectory. The magnetic field generating unit 10 may also rotate on a predetermined circumference.

[0031] FIG. 2C shows an example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged. This figure shows the magnetic field generating unit 10 and the magnetic sensor 20 from the perspective of the Z-axis direction. This figure is a top view showing the magnetic field generating unit 10 moving around a circle. In FIG. 2C, the magnetic field generating unit 10 moves so as to cross the magnetic sensor 20 in the XY plane. The magnetic field generating unit 10 crossing the magnetic sensor 20 means that the magnetic field generating unit 10 and the magnetic sensor 20 partially overlap in the XY plane. In other words, the magnetic field generating unit 10 may move so as to pass over the magnetic sensor 20. Furthermore, the magnetic field generating unit 10 does not have to pass over the magnetic sensor 20.

[0032] For example, the magnetic field generating unit 10 may move in response to the folding of a foldable smartphone (e.g., a foldable phone), or the magnetic field generating unit 10 may move in response to the rotation of the bezel of a smartwatch. In the case of a foldable phone, the magnetic field generating unit 10 may be provided on one side and the magnetic sensor 20 on the other side, and the magnetic field generating unit 10 may move along a curve in response to opening and closing. In the case of a smartwatch, the magnetic sensor 20 may be provided on the main body side and the magnetic field generating unit 10 on the bezel side, and the magnetic field generating unit 10 may rotate along a circle in response to the rotational drive of the bezel.

[0033] 3A shows a state in which the magnetic field generating unit 10 is disposed at a reference position P0. In this example, the magnetic field generating unit 10 is disposed so that the boundary between the north pole and the south pole is located above the magnetic sensor 20. In this example, the magnetic flux density Bx in the X-axis direction is greater than the magnetic flux density Bz in the Z-axis direction. However, the magnetic flux density detected by the magnetic sensor 20 at the reference position P0 is not limited to this.

[0034] FIG. 3B shows a state in which the magnetic field generating unit 10 is disposed at an event occurrence position Pe. That is, the event detection system 100 executes a predetermined process when the magnetic field generating unit 10 is disposed at the position shown in this figure. The magnetic field generating unit 10 in this example has moved toward the positive side of the X-axis direction from the reference position P0 in FIG. 3A. In this case, the component of the magnetic flux density Bz in the Z-axis direction is larger than when the magnetic field generating unit 10 is at the reference position P0 in FIG. 3A. The relative positional relationship between the magnetic field generating unit 10 and the magnetic sensor 20 and the direction of movement of the magnetic field generating unit 10 are not limited to this example, as long as the magnetic sensor 20 can detect the trigger threshold.

[0035] FIG. 3C shows magnetic field waveforms according to the position of the magnetic field generating unit 10. The horizontal axis indicates the position of the magnetic field generating unit 10 in the X-axis direction, and the vertical axis indicates the magnetic flux density Bz in the Z-axis direction. The magnitude of the magnetic flux density Bz measured by the magnetic sensor 20 changes as the magnetic field generating unit 10 moves. The magnetic flux density Bz_0 is the magnetic flux density detected by the magnetic sensor 20 when the magnetic field generating unit 10 is positioned at the reference position P0. The magnetic flux density Bz_1 is the magnetic flux density detected by the magnetic sensor 20 when the magnetic field generating unit 10 is positioned on the positive side of the X-axis direction from the reference position P0.

[0036] The magnetic flux density Bthz is the magnetic flux density detected by the magnetic sensor 20 when the magnetic field generating unit 10 is placed at the event occurrence position Pe. The event detection system 100 of this example generates a trigger signal when the magnetic sensor 20 exceeds the magnetic flux density Bthz. Note that, although this example has been described as using one detection axis for the sake of explanation, two or more detection axes may be used to detect an event.

[0037] Fig. 3D shows the changes in the magnetic flux density and trigger signal corresponding to the magnetic field waveform of Fig. 3C. In this example, from time T0 to time T1, the magnetic field generating unit 10 is stopped at the reference position P0, and there is no change in the magnetic flux density Bz.

[0038] At time T1, the magnetic field generating unit 10 starts moving from the reference position P0, and the magnetic flux density gradually increases from Bz_0. At time T2, when the magnetic flux density exceeds Bthz, a trigger signal is generated from the magnetic sensor 20. Thereafter, at time T3, the magnetic field generating unit 10 moves to a position corresponding to the magnetic flux density Bz_1 and stops there. At time T4, the magnetic field generating unit 10 starts moving to the reference position P0, and at time T5, when the magnetic flux density falls below Bthz, it stops generating the trigger signal. In this way, the event detection system 100 of this example generates a trigger signal based on a threshold determination inside the magnetic sensor 20.

[0039] An example of a threshold determination method using a biaxial magnetic field will be described below.

[0040] FIG. 4A shows an example of a threshold determination method using a biaxial magnetic field. In this example, as shown in FIGS. 2A and 2B, the magnetic field generating unit 10 moves across the magnetic sensor 20 in the XY plane. The event detection system 100 of this example selectively uses the magnetic flux density Bx in the X-axis direction and the magnetic flux density Bz in the Z-axis direction. However, the event occurrence position Pe corresponds to the vicinity of the inflection point of the magnetic flux density Bz in the Z-axis direction, and if the Z-axis is used as the detection axis, the event occurrence position Pe cannot be accurately detected. Therefore, the event detection system 100 of this example detects the event occurrence position Pe using the magnetic flux density Bx, which changes linearly at the event occurrence position Pe. The event detection system 100 of this example can expand the event detection area by performing threshold determination using measurement data from two or more axes.

[0041] In this embodiment, even when the magnetic field generating unit 10 moves in the XY plane without crossing the magnetic sensor 20, an event can be detected.

[0042] FIG. 4B shows an example of how to arrange the magnetic field generating unit 10 and the magnetic sensor 20. This figure shows the magnetic field generating unit 10 and the magnetic sensor 20 from the perspective of the Z-axis direction. In this example, the magnetic field generating unit 10 does not cross the magnetic sensor 20 on the XY plane, but moves to a position offset from the magnetic sensor 20 in the Y-axis direction. In FIG. 4B, the amount of movement y in the Y-axis direction is a positive value. That is, the magnetic field generating unit 10 moves by y in the positive direction of the Y-axis direction, but this is not limited to this.

[0043] FIG. 4C shows an example of how the magnetic field generating unit 10 and the magnetic sensor 20 are arranged. This figure shows the magnetic field generating unit 10 and the magnetic sensor 20 from the perspective of the Z-axis direction. In this example, the magnetic field generating unit 10 does not cross the magnetic sensor 20 in the XY plane, but moves to a position offset from the magnetic sensor 20 in the Y-axis direction. The magnetic field generating unit 10 may move in the positive direction of the X-axis in the XZ plane, and the amount of movement y in the Y-axis direction is a negative value. In other words, the magnetic field generating unit 10 may move by y in the negative direction of the Y-axis in the XY plane.

[0044] 4D shows a magnetic field waveform according to the position of the magnetic field generating unit 10. The horizontal axis indicates the position of the magnetic field generating unit 10 in the X-axis direction, and the vertical axis indicates the magnetic flux density Bx in the X-axis direction and the magnetic flux density Bz in the Z-axis direction. The magnitudes of the magnetic flux densities Bx and Bz measured by the magnetic sensor 20 change according to the movement of the magnetic field generating unit 10.

[0045] The dashed lines show the magnetic field waveforms (Bx, Bz) when the magnetic field generating unit 10 moves across the magnetic sensor 20 as in Fig. 2B, and the solid lines show the magnetic field waveforms (Bxoff, Bzoff) when the magnetic field generating unit 10 moves to a position shifted in the Y-axis direction from the magnetic sensor 20 as in Fig. 4C. In the case of Fig. 4C, the distance between the magnetic field generating unit 10 and the magnetic sensor 20 is greater than in the case of Fig. 2B, and therefore the magnetic flux density detected by the magnetic sensor 20 decreases.

[0046] 4D, in the XY plane, the position in the X-axis direction of the magnetic field generating unit 10 that gives the peak of the magnetic flux density does not change significantly between when the magnetic field generating unit 10 crosses the magnetic sensor 20 and when it moves to a position shifted in the Y-axis direction from the magnetic sensor 20. Therefore, even when the magnetic field generating unit 10 does not cross the magnetic sensor 20 in the XY plane, the same event detection method as when it crosses the magnetic sensor 20 can be applied.

[0047] Here, the strength of the magnetic flux density detected by the magnetic sensor 20 decreases as the amount of movement y in the Y-axis direction of the magnetic field generating unit 10 increases. Although not shown, the strength of the magnetic flux density detected by the magnetic sensor 20 in the case of Fig. 4B is smaller than the strength of the magnetic flux density detected by the magnetic sensor 20 in the case of Fig. 4C.

[0048] Therefore, the movement amount y of the magnetic field generating unit 10 can be determined in consideration of the magnetic flux density at the position of the magnetic sensor 20 at which an event can be detected, including the influence of external magnetic field noise, etc. In this way, the degree of freedom in arranging the magnetic field generating unit 10 and the magnetic sensor 20 is increased, and therefore the degree of freedom in designing the housing can also be increased.

[0049] FIG. 5 shows a comparative example of a threshold determination method using a uniaxial magnetic field. In this example, the event occurrence position Pe corresponds to the vicinity of the inflection point of the magnetic flux density Bz in the Z-axis direction, making it difficult to accurately determine the position of the magnetic field generating unit near the event occurrence position Pe. Therefore, the threshold determination method of the comparative example generates an undetectable region Ru where an event cannot be detected. Therefore, the method of the comparative example limits the detectable event occurrence position Pe.

[0050] FIG. 6 shows a more specific example of a threshold determination method. The event detection system 100 of this example selects and uses one of the detection axes depending on the position in the X-axis direction. The solid line in the graph indicates a detectable area where the position of the magnetic field generating unit 10 can be detected. The dashed line in the graph indicates an undetectable area where the position of the magnetic field generating unit 10 cannot be detected. In one example, the detectable area is an area that does not have an inflection point in the magnetic flux density and monotonically increases or monotonically decreases as the magnetic field generating unit 10 moves. The undetectable area is an area where the magnetic flux density waveform has an inflection point or where the magnetic flux density changes little as the magnetic field generating unit 10 moves.

[0051] The selector 34 selects the X-axis when the event occurrence position Pe belongs to a detectable region on the X-axis where the position of the magnetic field generating unit 10 can be detected. On the other hand, the selector 34 selects the Z-axis when the event occurrence position Pe does not belong to a detectable region on the X-axis but belongs to a detectable region on the Z-axis. The selector 34 may also select the detection axis based on the reference position P0 and the event occurrence position Pe.

[0052] The event detection system 100 of this example divides the area into five regions: region R1, region R2, region R3, region R1', and region R2', and selects axes for each region. The selector 34 selects the Z axis as the detection axis in regions R1, R3, and R1'. The selector 34 selects the X axis as the detection axis in regions R2 and R2'.

[0053] Region R1 is the section between the start point and boundary 1, and the trigger threshold can be determined using the monotonically decreasing magnetic flux density Bz. Region R2 is the section between boundary 1 and boundary 2, and the trigger threshold can be determined using the monotonically decreasing magnetic flux density Bx. Region R3 is the section between boundary 2 and boundary 2', and the trigger threshold can be determined using the monotonically increasing magnetic flux density Bz. Region R2' is the section between boundary 2' and boundary 1', and the trigger threshold can be determined using the monotonically increasing magnetic flux density Bx. Region R1' is the section between boundary 1' and the end point, and the trigger threshold can be determined using the monotonically decreasing magnetic flux density Bz. The method of setting the regions is not limited to this.

[0054] As described above, the event detection system 100 sets each region and selects a detection axis so that the magnetic flux density of the selected axis does not have an inflection point, which allows the event detection system 100 to determine the trigger threshold and generate a trigger signal over a wider range.

[0055] In this embodiment, when multiple trigger thresholds can be set for each detection axis, event detection can be performed when the magnetic field generating unit 10 moves in the positive or negative direction of the X axis. Also, in this embodiment, event detection can be performed even when only one trigger threshold can be set for each detection axis.

[0056] As an example, a method for detecting an event when the magnetic field generating unit 10 moves from the reference position P0 will be described below. Although a method for detecting an event when the magnetic field generating unit 10 moves in the positive or negative direction of the X axis will be described below, the moving direction of the magnetic field generating unit 10 is not limited to this.

[0057] 7A shows magnetic field waveforms according to the position of the magnetic field generating unit 10. The horizontal axis indicates the position of the magnetic field generating unit 10 in the X-axis direction, and the vertical axis indicates the magnetic flux density Bx in the X-axis direction and the magnetic flux density Bz in the Z-axis direction. When the magnetic field generating unit 10 moves in the positive or negative direction of the X-axis near the reference position P0, if neither Bx nor Bz includes an inflection point, it is possible to detect an event when the magnetic field generating unit 10 moves ±1 mm from the reference position P0.

[0058] For example, in FIG. 7A, when the reference position P0 is 2 mm, the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side is Bx, and the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side is Bz. By performing event detection for each of these, event detection can be performed even when only one trigger threshold can be set for each detection axis.

[0059] However, for example, when the reference position P0 is 0 mm in FIG. 7A, the change in Bx around the reference position P0 is small, so event detection using Bx is not possible. Even in such a case, if the magnetic sensor 20 can calculate the square root of the sum of squares Bsum of the magnetic flux density, event detection is possible. That is, event detection can be performed by calculating the trigger threshold corresponding to the event occurrence position Pe using the square root of the sum of squares Bsum. The square root of the sum of squares Bsum of the magnetic flux density can be expressed by the following equation 1.

number

[0060] 7B shows magnetic field waveforms according to the position of the magnetic field generating unit 10. The horizontal axis represents the position of the magnetic field generating unit 10 in the X-axis direction, and the vertical axis represents the magnetic flux density Bx in the X-axis direction, the magnetic flux density Bz in the Z-axis direction, and the square root of the sum of the squares Bsum of the magnetic flux densities. For example, when the reference position P0 is 0 mm, by using Bsum, which has a bilaterally symmetrical shape, it is possible to detect events when the reference position P0 is moved ±1 mm.

[0061] FIG. 7C shows the magnetic field waveform according to the position of the magnetic field generating unit 10. In FIG. 7C, the reference position P0 is 0 mm, as in FIG. 7B. In FIG. 7C, event detection is performed using Bz as the trigger threshold according to the event occurrence position Pe+ when moved to the plus side, and Bsum as the trigger threshold according to the event occurrence position Pe- when moved to the minus side. This allows event detection to be performed even when only one trigger threshold can be set for each detection axis.

[0062] Figure 7D shows the case where the reference position P0 is 1 mm. In Figure 7D, event detection is performed using Bsum as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and Bz as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side, so that event detection can be performed even when only one trigger threshold can be set for each detection axis.

[0063] 7E shows the case where the reference position P0 is −1 mm. In FIG. 7E, the trigger threshold Bz is used as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and the trigger threshold Bsum is used as the trigger threshold corresponding to the event occurrence position Pe− when moved to the minus side, thereby enabling event detection even when only one trigger threshold can be set for each detection axis.

[0064] As described above, the event detection system 100 can detect events in both directions by using the square root of the sum of the squares of the magnetic flux densities, Bsum. This allows the event detection system 100 to determine the trigger threshold and generate a trigger signal even when only one trigger threshold can be set for the selected detection axis.

[0065] Furthermore, in this embodiment, if only one trigger threshold can be set for each detection axis, event detection can be performed even if the magnetic sensor 20 cannot calculate the square root of the sum of the squares Bsum of the magnetic flux density.

[0066] 8A shows the magnetic field waveform according to the position of the magnetic field generating unit 10 when the magnetic field generating unit 10 does not cross the magnetic sensor 20, as shown in FIG. 4C. The horizontal axis represents the position of the magnetic field generating unit 10 in the X-axis direction, and the vertical axis represents the magnetic flux density Bx in the X-axis direction, the magnetic flux density By in the Y-axis direction, and the magnetic flux density Bz in the Z-axis direction. When the magnetic field generating unit 10 moves in the positive or negative direction of the X-axis near the reference position P0, if neither Bx nor Bz includes an inflection point, it is possible to detect an event when the magnetic field generating unit 10 moves ±1 mm from the reference position P0.

[0067] For example, in FIG. 8A, when the reference position P0 is 2 mm, the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side is Bx, and the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side is Bz. By performing event detection for each of these, event detection can be performed even when only one trigger threshold can be set for each detection axis.

[0068] However, for example, when the reference position P0 is 0 mm in Figure 8A, the change in Bx around the reference position P0 is small, so event detection using Bx is not possible. Even in such a case, event detection can be performed by selecting the Y axis as the detection axis and using By.

[0069] 8B is a diagram illustrating a case where the reference position P0 is 0 mm. In this embodiment, the trigger threshold Bz is used as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and the trigger threshold By is used as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side, thereby enabling event detection even when only one trigger threshold can be set for each detection axis. However, this is not limiting. That is, event detection can be performed by using By as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and using Bz as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side.

[0070] FIG. 8C shows a case where the reference position P0 is 1 mm. In this embodiment, the trigger threshold Bz is used as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and the trigger threshold By is used as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side, thereby enabling event detection even when only one trigger threshold can be set for each detection axis. However, this is not limiting. That is, event detection can be performed by using By as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and using Bz as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side.

[0071] 8D shows a case where the reference position P0 is -1 mm. In this embodiment, the trigger threshold Bz is used as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and the trigger threshold By is used as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side, thereby enabling event detection even when only one trigger threshold can be set for each detection axis. However, this is not limiting. That is, event detection can be performed by using By as the trigger threshold corresponding to the event occurrence position Pe+ when moved to the plus side, and using Bz as the trigger threshold corresponding to the event occurrence position Pe- when moved to the minus side.

[0072] 9 shows an example of the operation flow of the event detection system 100. This example shows a method of detecting a predetermined event after the processing unit 30 has transitioned to a standby state and generating a trigger signal for activating the processing unit 30.

[0073] Steps S300 to S314 may be executed by the processing unit 30, and steps S200 to S206 may be executed by the magnetic sensor 20. In step S300, the processing unit 30 is set to an activated state. In step S302, a request is made to the magnetic sensor 20 to read measurement data in order to acquire measurement data at the reference position P0 of the magnetic field generating unit 10. As a result, the processing unit 30 acquires measurement data (Bx, By, Bz) at the reference position P0 from the magnetic sensor 20. The reference position P0 of the magnetic field generating unit 10 is not particularly limited.

[0074] In step S304, the processing unit 30 determines, from the acquired measurement data, the region of the reference position P0 of the magnetic field generating unit 10. For example, the processing unit 30 calculates the reference position P0 of the magnetic field generating unit 10 using a data table created in advance or function fitting.

[0075] In step S306, the processing unit 30 determines the area of ​​the event occurrence position Pe. The processing unit 30 may store a preset event occurrence position Pe. The processing unit 30 may determine the area of ​​the event occurrence position Pe from measurement data when the magnetic field generating unit 10 is located at the event occurrence position Pe. In step S308, the processing unit 30 calculates a trigger threshold based on the event occurrence position Pe. The processing unit 30 may calculate the trigger threshold using a data table created in advance or function fitting.

[0076] In step S310, the processing unit 30 writes the calculated trigger threshold to the magnetic sensor 20. As a result, in step S202, the detection axis to be used and the trigger threshold are set in the magnetic sensor 20. The magnetic sensor 20 does not need to use axes that are not required for determining the trigger threshold and does not need to detect the magnetic flux density. The magnetic sensor 20 measures the magnetic field, and outputs a trigger signal to the processing unit 30 when the magnetic field exceeds or falls below the set trigger threshold (steps S204 and S206). Then, the processing unit 30 enters an activated state upon receiving the trigger signal (step S314).

[0077] Fig. 10 shows an example of the configuration of an event detection system 100. The event detection system 100 of this example differs from the embodiment of Fig. 2A in that it includes multiple magnetic sensors 20. The event detection system 100 of this example includes two magnetic sensors 20: magnetic sensor 20a and magnetic sensor 20b.

[0078] The magnetic sensors 20a and 20b are arranged in the X-axis direction, which is the movement direction of the magnetic field generating unit 10. The magnetic sensors 20a and 20b may be the same type of magnetic sensor or different types of magnetic sensors. The magnetic sensor 20b may or may not overlap with the event detection area of ​​the magnetic sensor 20a.

[0079] The event detection system 100 can further expand the event detectable region by providing multiple magnetic sensors 20. The processing unit 30 may select the magnetic sensor 20 to be used by a process similar to the process for determining the detection axis when there is one magnetic sensor 20, and determine the detection axis from among the selected magnetic sensors 20. This allows the event detection system 100 to use the optimal detection axis in the optimal magnetic sensor 20 according to the event occurrence position Pe.

[0080] 11 illustrates an example of a computer 2200 in which aspects of the present invention may be embodied, in whole or in part. Programs installed on the computer 2200 may cause the computer 2200 to function as or perform operations associated with an apparatus or one or more sections of the apparatus according to embodiments of the present invention, and / or to perform a process or steps of the process according to embodiments of the present invention. Such programs may be executed by the CPU 2212 to cause the computer 2200 to perform specific operations associated with some or all of the blocks of the flowcharts and block diagrams described herein.

[0081] A computer 2200 according to this embodiment includes a CPU 2212, a RAM 2214, a graphics controller 2216, and a display device 2218, which are interconnected by a host controller 2210. The computer 2200 also includes input / output units such as a communication interface 2222, a hard disk drive 2224, a DVD-ROM drive 2226, and an IC card drive, which are connected to the host controller 2210 via an input / output controller 2220. The computer also includes legacy input / output units such as a ROM 2230 and a keyboard 2242, which are connected to the input / output controller 2220 via an input / output chip 2240.

[0082] The CPU 2212 operates according to programs stored in the ROM 2230 and RAM 2214, thereby controlling each unit. The graphics controller 2216 acquires image data generated by the CPU 2212 into a frame buffer or the like provided in the RAM 2214 or into the graphics controller 2216 itself, and causes the image data to be displayed on the display device 2218.

[0083] The communication interface 2222 communicates with other electronic devices via a network. The hard disk drive 2224 stores programs and data used by the CPU 2212 in the computer 2200. The DVD-ROM drive 2226 reads programs or data from the DVD-ROM 2201 and provides the programs or data to the hard disk drive 2224 via the RAM 2214. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0084] The ROM 2230 stores therein a boot program or the like that is executed by the computer 2200 upon activation, and / or programs that depend on the hardware of the computer 2200. The input / output chip 2240 may also connect various input / output units to the input / output controller 2220 via a parallel port, a serial port, a keyboard port, a mouse port, etc.

[0085] The programs are provided by a computer-readable medium such as a DVD-ROM 2201 or an IC card. The programs are read from the computer-readable medium, installed in the hard disk drive 2224, RAM 2214, or ROM 2230, which are also examples of computer-readable media, and executed by the CPU 2212. Information processing described in these programs is read by the computer 2200, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be configured by realizing information manipulation or processing in accordance with the use of the computer 2200.

[0086] For example, when communication is performed between the computer 2200 and an external device, the CPU 2212 may execute a communication program loaded into the RAM 2214 and instruct the communication interface 2222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 2212, the communication interface 2222 reads transmission data stored in a transmission buffer processing area provided in the RAM 2214, the hard disk drive 2224, the DVD-ROM 2201, or a recording medium such as an IC card, and transmits the read transmission data to the network, or writes reception data received from the network to a reception buffer processing area or the like provided on the recording medium.

[0087] Furthermore, the CPU 2212 may cause all or a necessary portion of a file or database stored on an external recording medium such as the hard disk drive 2224, the DVD-ROM drive 2226 (DVD-ROM 2201), an IC card, etc. to be read into the RAM 2214, and perform various types of processing on the data on the RAM 2214. The CPU 2212 then writes back the processed data to the external recording medium.

[0088] Various types of information, such as various types of programs, data, tables, and databases, may be stored on the recording medium and subjected to information processing. The CPU 2212 may perform various types of processing on data read from the RAM 2214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequences of the programs, and write the results back to the RAM 2214. The CPU 2212 may also search for information in a file, database, etc. on the recording medium. For example, if multiple entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored on the recording medium, the CPU 2212 may search for an entry that matches a condition specified by the attribute value of the first attribute from among the multiple entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0089] The above-described programs or software modules may be stored in a computer-readable medium on or near the computer 2200. A recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet can also be used as a computer-readable medium, thereby providing the programs to the computer 2200 via the network.

[0090] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the claims that such modifications and improvements can also be included within the technical scope of the present invention.

[0091] It should be noted that the execution order of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and that the processes can be performed in any order unless the output of a previous process is used in a subsequent process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, this does not mean that the processes must be performed in this order. [Explanation of symbols]

[0092] 10···magnetic field generation unit, 20···magnetic sensor, 22···detection unit, 24···output unit, 30···processing unit, 32···acquisition unit, 34···selection unit, 36···calculation unit, 100···event detection system, 2200···computer, 2201···DVD-ROM, 2210···host controller, 2212···CPU, 2214···RAM, 2216···graphics controller, 2218···display device, 2220···input / output controller, 2222···communication interface, 2224··hard disk drive, 2226··DVD-ROM drive, 2230···ROM, 2240···input / output chip, 2242···keyboard

Claims

1. 1. An event detection method for detecting an event according to a position of a predetermined magnetic field generation unit by detecting magnetic fields of two or more axes generated by the magnetic field generation unit using a magnetic sensor, acquiring an event occurrence position based on the magnetic field detected by the magnetic sensor; selecting a detection axis for detecting an event based on the event occurrence location; calculating a trigger threshold value according to the event occurrence position on the detection axis; obtaining a trigger signal indicating that the magnetic field detected by the magnetic sensor and the trigger threshold satisfy a predetermined condition; An event detection method comprising:

2. moving the magnetic field generating unit in a predetermined first direction; selecting a first axis parallel to the first direction or a second axis perpendicular to the first axis as the detection axis; The event detection method of claim 1 , comprising:

3. The step of moving the magnetic field generating unit in a predetermined first direction includes the step of moving the magnetic field generating unit in the first axis or the second axis so that the magnetic field generating unit passes over the magnetic sensor. The event detection method according to claim 2 .

4. The step of selecting a detection axis comprises: selecting the first axis when the event occurrence position belongs to a detectable region where the position of the magnetic field generation unit can be detected on the first axis; selecting the second axis when the event occurrence position does not belong to a detectable area of ​​the first axis but belongs to a detectable area of ​​the second axis. The event detection method according to claim 2 or 3.

5. acquiring a reference position of the magnetic field generating unit; selecting the detection axis based on the reference position and the event occurrence position; The event detection method according to claim 1 , comprising:

6. calculating the square root of the sum of the squares of the magnetic fields detected by the magnetic sensors; calculating a trigger threshold value according to the event occurrence position using the square root of the sum of squares; The event detection method according to claim 1 , comprising:

7. a magnetic field generating unit that generates a predetermined magnetic field; a magnetic sensor for detecting the magnetic field generated by the magnetic field generating unit; a processing unit that processes a signal detected by the magnetic sensor; Equipped with The processing unit an acquisition unit that acquires an event occurrence position based on the magnetic field detected by the magnetic sensor; a selection unit that selects a detection axis for event detection based on the event occurrence position; a calculation unit that calculates a trigger threshold value according to the event occurrence position on the detection axis; and an output unit that outputs a trigger signal indicating that the magnetic field detected by the magnetic sensor and the trigger threshold satisfy a predetermined condition; Event detection system.

8. The selection unit selects, as the detection axis, a first axis parallel to a predetermined first direction in which the magnetic field generation unit moves, or a second axis perpendicular to the first axis. The event detection system of claim 7 .

9. The magnetic field generating unit has north and south poles arranged in the first direction. The event detection system of claim 8 .

10. a plurality of magnetic sensors arranged in the first direction; The event detection system according to claim 8 or 9.

11. The magnetic sensor is a multi-axis magnetic sensor capable of detecting magnetic fields along two or more axes. An event detection system according to any one of claims 7 to 10.

12. the storage processing unit calculates a square root of the sum of squares of the magnetic fields detected by the magnetic sensor; Calculating a trigger threshold value according to the event occurrence position using the square root of the sum of squares An event detection system according to any one of claims 7 to 11.

13. A program for causing a computer to execute the event detection method according to any one of claims 1 to 6.

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