Inertial sensor module and inertial measurement system

Abstract

To provide an inertial sensor module capable of externally changing the format of output data.SOLUTION: An inertial measurement system includes a first inertial sensor, a second inertial sensor, and a processing device that receives a first detection signal output from the first inertial sensor and a second detection signal output from the second inertial sensor, and outputs measurement data based on the first detection signal and the second detection signal based on output instruction information input from the outside. The processing device outputs the measurement data in a format according to output format selection information input from the outside.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] This invention relates to an inertial sensor module and an inertial measurement system. [Background technology]

[0002] Patent Document 1 describes an inertial sensor module having an inertial sensor and an IC chip that outputs a predetermined signal based on a signal from the inertial sensor. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2016-31358 [Overview of the project] [Problems that the invention aims to solve]

[0004] In recent years, the applications of inertial sensor modules have diversified, and it is desirable that host devices connected to inertial sensor modules be able to select and acquire a series of data necessary for the application from among the various data generated inside the inertial sensor module. However, the inertial sensor module described in Patent Document 1 outputs a predetermined signal, and the format of the output signal cannot be changed. [Means for solving the problem]

[0005] One embodiment of the inertial sensor module according to the present invention is: First inertial sensor and, The second inertial sensor, A processing device that receives a first detection signal output from the first inertial sensor and a second detection signal output from the second inertial sensor, and outputs measurement data based on the first detection signal and the second detection signal based on output instruction information input from an external source, Equipped with, The processing device outputs the measurement data in a format corresponding to the output format selection information input from an external source.

[0006] One aspect of the inertial measurement system according to the present invention is: One embodiment of the inertial sensor module, A monitoring device that monitors the measurement data and transmits the output format selection information corresponding to the monitoring result to the processing device, It is equipped with. [Brief explanation of the drawing]

[0007] [Figure 1] A perspective view showing how the inertial sensor module of the first embodiment is fixed to the mounting surface. [Figure 2] A perspective view of the inertial sensor module as seen from the mounting surface. [Figure 3] Exploded perspective view of the inertial sensor module. [Figure 4] Perspective view of the circuit board. [Figure 5] A diagram showing the configuration of the inertial measurement system of the first embodiment. [Figure 6] A diagram showing an example of the processing unit configuration. [Figure 7] A diagram showing an example of the format of measurement data in the first embodiment. [Figure 8] A diagram showing an example of the format of measurement data in the second embodiment. [Figure 9] A diagram showing an example of the measurement data format in the third embodiment. [Figure 10] A diagram showing the configuration of the inertial measurement system according to the fourth embodiment. [Figure 11] A diagram showing a modified version of the inertial sensor module. [Figure 12] A diagram showing a modified version of the inertial sensor module. [Modes for carrying out the invention]

[0008] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. The embodiments described below are not intended to unduly limit the scope of the present invention as described in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0009] 1. First Embodiment 1-1. Structure of the inertial sensor module Figure 1 is a perspective view showing how the inertial sensor module used in the inertial measurement system of the first embodiment is fixed to the mounting surface. Figure 2 is a perspective view of the inertial sensor module as seen from the mounting surface side. First, an overview of the inertial sensor module 2 in the first embodiment will be described. The inertial sensor module 2 detects the behavior of the mounting object, such as an automobile or a robot.

[0010] As shown in Figure 1, the inertial sensor module 2 has a roughly square rectangular parallelepiped shape, and is compactly constructed with a side length of only a few centimeters. Two notches 52 are provided in the diagonal direction of the inertial sensor module 2. The inertial sensor module 2 is fixed to the mounting surface 81 of an object to be mounted, such as an automobile, by two screws 80 inserted through the notches 52. The object to be mounted is not limited to moving objects such as automobiles, but may also be structures such as bridges or elevated railway tracks. When attached to a structure, it can be used, for example, as a structural health monitoring system to check the structural integrity of the building.

[0011] As shown in Figure 2, the inertial sensor module 2 has a configuration in which an inner case 70 is housed inside a rectangular parallelepiped outer case 51. A rectangular opening 71 is formed in the inner case 70. Hereafter, the direction of the longer side of this opening 71 will be referred to as the Y(+) direction. The direction perpendicular to the Y(+) direction will be referred to as the X(+) direction, and the thickness direction of the outer case 51 will be referred to as Z(+) in the coordinate axes for explanation. A plug-type connector 66 is exposed from the opening 71 of the inner case 70, and the Y(+) direction coincides with the arrangement direction of the multiple pins in the connector 66. This coordinate axis is the detection axis of the inertial sensor module 2.

[0012] Figure 3 is an exploded perspective view of the inertial sensor module 2. As shown in Figure 3, the inertial sensor module 2 consists of an outer case 51, a connecting member 60, a circuit board 65, an inner case 70, and the like.

[0013] The outer case 51 is a box-shaped housing with a rectangular prism shape. The material of the outer case 51 is, for example, aluminum, but it may be other metals or ceramics. Two notched holes 52, as described above, are formed on the outside of the outer case 51. However, through holes such as round holes may be formed in the outer case 51 and these through holes may be fastened with screws. Alternatively, flanges may be formed on the sides of the outer case 51 and the flange portions may be fastened with screws.

[0014] The outer case 51 is provided with a storage section 55 for housing the inner case 70 with the circuit board 65 set inside. The storage section 55 consists of a first recess 53 with the bottom 53a as its base and a second recess 54 having a receiving section 54a surrounding the first recess 53. The circuit board 65 is housed in the first recess 53. The receiving section 54a is a ring-shaped receiving section of the inner case 70 that rises in a stepped manner from the bottom 53a, and the second recess 54 has a connecting section. The inner case 70 is housed via member 60. The joining member 60 is a resin cushioning member positioned between the outer case 51 and the inner case 70. The joining member 60 is a ring-shaped member similar to the receiving portion 54a and is set on top of the receiving portion 54a.

[0015] The inner case 70 is a component that supports the circuit board 65 and is shaped to be housed in the second recess 54 of the outer case 51. The inner case 70 is made of the same material as the outer case 51. The inner case 70 is provided with an opening 71 for exposing the connector 66 of the circuit board 65 to the outside and a third recess 73 for housing the electronic components mounted on the circuit board 65. In reality, the third recess 73 is filled with resin, but this is omitted from the illustration in Figure 3. Similarly, the first recess 53 of the housing section 55 in the outer case 51 can also be filled with resin, but this is omitted from the illustration in Figure 3.

[0016] In this configuration, the inner case 70, which includes the circuit board 65, is housed and integrated within the outer case 51. As shown in Figure 1, the inertial sensor module 2 is fixed to the mounting surface 81 of the mounting object with two screws 80 for use.

[0017] Figure 4 is a perspective view of the circuit board 65. The circuit board 65 is a multilayer substrate with multiple through-holes, and a glass epoxy substrate is used. However, the circuit board 65 is not limited to a glass epoxy substrate; any rigid substrate capable of mounting multiple inertial sensors, electronic components, connectors, etc., may be used, for example, a composite substrate or a ceramic substrate. The outer shape of the circuit board 65 is formed as a modified octagon with a portion cut out in a plan view. The Z(+) side of the circuit board 65 is called the first surface 65a, and the surface opposite to the first surface 65a is called the second surface 65b.

[0018] As shown in Figure 4, the first surface 65a of the circuit board 65 is equipped with a connector 66, a first inertial sensor 10, a second inertial sensor 20, and the like. The connector 66 is a plug-type connector and has two rows of connection terminals with multiple pins arranged at equal pitches. The number of terminals may be changed as appropriate according to the design specifications.

[0019] The first inertial sensor 10 is a sensor having six detection axes, and is a 6DOF sensor that detects angular velocity around the X, Y, and Z axes and acceleration in the X, Y, and Z axis directions. DOF stands for Degrees of Freedom. For example, the first inertial sensor 10 is a capacitive sensor made by processing a silicon substrate using MEMS technology. MEMS stands for Micro Electro Mechanical Systems.

[0020] The second inertial sensor 20 is a sensor that detects inertia in one axis, and is, for example, a gyro sensor that detects angular velocity around the Z axis. For example, the second inertial sensor 20 has a sensor element made of quartz and is a vibration gyro sensor that detects angular velocity from the Coriolis force applied to a vibrating object. However, the second inertial sensor 20 may have a sensor element made of ceramic, silicon, or the like.

[0021] The processing unit 30 is mounted on the second side 65b of the circuit board 65. However, the processing unit 30 may also be mounted on the first side 65a of the circuit board 65. The processing unit 30 is, for example, an MCU and is configured as a single-chip IC. MCU stands for Micro Controller Unit. The first inertial sensor 10 and the second inertial sensor 20 are each connected to the processing unit 30 by wiring (not shown) provided on the circuit board 65. In addition, the circuit board 65 may also have several other electronic components mounted on it, such as temperature sensors.

[0022] 1-2. Configuration of the Inertial Measurement System Next, the configuration and function of the inertial measurement system 1 of the first embodiment using the inertial sensor module 2 will be described. The functional configuration of the inertial sensor module 2 will also be described. Figure 5 is a diagram showing the configuration of the inertial measurement system 1 of the first embodiment. As shown in Figure 5, the inertial measurement system 1 of the first embodiment comprises an inertial sensor module 2 and a host device 3.

[0023] The inertial sensor module 2 comprises a first inertial sensor 10, a second inertial sensor 20, a processing unit 30, and a temperature sensor 40. Note that the inertial sensor module 2 may have some of the components shown in Figure 5 omitted or modified, or other components added.

[0024] The first inertial sensor 10 is a sensor that uses the first, second, third, fourth, fifth, and sixth axes as detection axes, and includes a first sensor element 11, a second sensor element 12, a third sensor element 13, a fourth sensor element 14, a fifth sensor element 15, a sixth sensor element 16, and a processing circuit 17. For example, the first inertial sensor 10 may be a device in which a silicon substrate on which the first sensor element 11, second sensor element 12, third sensor element 13, fourth sensor element 14, fifth sensor element 15, sixth sensor element 16 and processing circuit 17 are formed is housed in a package, i.e., a silicon MEMS sensor. The first inertial sensor 10 has terminals TCS1, TCK1, TDI1, TDO1, and TR1, which are external connection terminals provided on the package.

[0025] The first sensor element 11 is a sensor element that detects physical quantities using the first axis as the detection axis. These physical quantities include, for example, angular velocity, acceleration, angular acceleration, speed, distance, pressure, sound pressure, or magnetic quantity.

[0026] The second sensor element 12 is a sensor element that detects a physical quantity using a second axis different from the first axis as its detection axis. The third sensor element 13 is a sensor element that detects a physical quantity using a third axis different from the first and second axes as its detection axis. The physical quantities detected by the first sensor element 11, the second sensor element 12, and the third sensor element 13 may be of the same type or of different types.

[0027] The fourth sensor element 14 is a sensor element that detects a physical quantity using the fourth axis as the detection axis. The fifth sensor element 15 is a sensor element that detects a physical quantity using the fifth axis, which is different from the fourth axis, as the detection axis. The sixth sensor element 16 is a sensor element that detects a physical quantity using the sixth axis, which is different from the fourth and fifth axes, as the detection axis. The physical quantities detected by the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16 may be of the same type or of different types. Furthermore, the fourth axis, the fifth axis, and the sixth axis may be the same axis as the first axis, the second axis, and the third axis, or they may be different axes.

[0028] For example, the first and fourth axes may both be the Z-axis, the second and fifth axes may both be the X-axis, and the third and sixth axes may both be the Y-axis. The first sensor element 11 may detect angular velocity around the Z-axis, the second sensor element 12 may detect angular velocity around the X-axis, the third sensor element 13 may detect angular velocity around the Y-axis, the fourth sensor element 14 may detect acceleration in the Z-axis direction, the fifth sensor element 15 may detect acceleration in the X-axis direction, and the sixth sensor element 16 may detect acceleration in the Y-axis direction.

[0029] The processing circuit 17 performs physical quantity detection processing on the signals output from the first sensor element 11, the second sensor element 12, the third sensor element 13, the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16, and outputs the first detection signal SD1 obtained by the detection processing. The system includes a detection circuit 171 that performs physical quantity detection processing on signals output from the third sensor element 13, the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16, respectively, and an interface circuit 172 that outputs a first detection signal SD1 obtained by the detection processing of the detection circuit 171.

[0030] The detection circuit 171 acquires signals output from the first sensor element 11, second sensor element 12, third sensor element 13, fourth sensor element 14, fifth sensor element 15, and sixth sensor element 16 at predetermined intervals, performs predetermined calculations, and generates a first detection signal SD1. The first detection signal SD1 includes a first axis detection signal obtained based on the output signal of the first sensor element 11, a second axis detection signal obtained based on the output signal of the second sensor element 12, and a third axis detection signal obtained based on the output signal of the third sensor element 13. Furthermore, the first detection signal SD1 includes a fourth axis detection signal obtained based on the output signal of the fourth sensor element 14, a fifth axis detection signal obtained based on the output signal of the fifth sensor element 15, and a sixth axis detection signal obtained based on the output signal of the sixth sensor element 16. In addition, each time the detection circuit 171 completes the generation of the first detection signal SD1, it generates a first data ready signal DRDY1 to indicate that the first detection signal SD1 is ready. The first detection signal SD1 is output to the interface circuit 172, and the first data ready signal DRDY1 is output from terminal TR1 and input to terminal TMR1 of the processing unit 30.

[0031] The interface circuit 172 acquires the first detection signal SD1 output from the detection circuit 171 in response to a read command input from the processing unit 30, and outputs the acquired first detection signal SD1 to the processing unit 30.

[0032] The second inertial sensor 20 is a sensor with the first axis as the detection axis, and includes a sensor element 21 and a processing circuit 22. For example, the second inertial sensor 20 may be a device in which a printed circuit board on which the sensor element 21 and the processing circuit 22 are mounted is housed in a package. The processing circuit 22 may be, for example, an IC chip realized by semiconductors. IC stands for Integrated Circuit. The second inertial sensor 20 has terminals TCS2, TCK2, TDI2, TDO2 and TR2, which are external connection terminals provided on the package.

[0033] Sensor element 21 is a sensor element that detects a physical quantity using the same first axis as the detection axis of the first sensor element 11 included in the first inertial sensor 10. Sensor element 21 may detect the same type of physical quantity as the first sensor element 11. For example, both sensor element 21 and the first sensor element 11 may detect angular velocity around the Z axis.

[0034] The processing circuit 22 performs physical quantity detection processing on the signal output from the sensor element 21 and outputs a second detection signal SD2 obtained by the detection processing. The processing circuit 22 includes a detection circuit 221 that performs physical quantity detection processing on the signal output from the sensor element 21, and an interface circuit 222 that outputs a second detection signal SD2 obtained by the detection processing of the detection circuit 221.

[0035] The detection circuit 221 acquires the signal output from the sensor element 21 at predetermined intervals and generates a second detection signal SD2 by performing predetermined calculations. The second detection signal SD2 includes the detection signal of the first axis obtained based on the output signal of the sensor element 21. In addition, each time the detection circuit 221 completes the generation of the second detection signal SD2, it generates a second data ready signal DRDY2 to indicate that the second detection signal SD2 is ready. The second detection signal SD2 is output to the interface circuit 222, and the second data ready signal DRDY2 is output from terminal TR2 and input to terminal TMR2 of the processing unit 30.

[0036] The interface circuit 222 acquires the second detection signal SD2 output from the detection circuit 221 in response to a read command input from the processing unit 30, and outputs the acquired second detection signal SD2 to the processing unit 30.

[0037] The inertial sensor module 2 includes a digital interface bus BS that electrically connects the first inertial sensor 10 and the second inertial sensor 20 to the processing unit 30.

[0038] The digital interface bus BS is a bus that conforms to the communication standard for interface processing performed by interface circuits 172 and 222. In this embodiment, the digital interface bus BS is a bus that conforms to the SPI communication standard and includes two data signal lines, a clock signal line, and a chip select signal line. SPI stands for Serial Peripheral Interface. Specifically, the first inertial sensor 10 is electrically connected to the digital interface bus BS via terminals TCS1, TCK1, TDI1, and TDO1. The second inertial sensor 20 is electrically connected to the digital interface bus BS via terminals TCS2, TCK2, TDI2, and TDO2. The processing unit 30 is electrically connected to the digital interface bus BS via terminals TMCS, TMCK, TMDO, and TMDI. Here, electrically connected means that electrical signals can be transmitted, and that information can be transmitted by electrical signals. However, the digital interface bus BS may be a bus that conforms to the I2C communication standard, a communication standard that is an evolution of SPI or I2C, or a communication standard that is an improved or modified version of part of the SPI or I2C standard. I2C is an abbreviation for Inter-Integrated Circuit.

[0039] The processing unit 30 is a master controller for the first inertial sensor 10 and the second inertial sensor 20. The processing unit 30 is an integrated circuit device, and is implemented by a processor such as an MCU. Alternatively, the processing unit 30 may be implemented by an ASIC with automatic placement and routing, such as a gate array.

[0040] The processing unit 30 outputs a chip select signal XMCS from terminal TMCS, a serial clock signal MSCLK from terminal TMCK, and a serial data signal MSDI from terminal TMDO. The interface circuit 172 performs SPI communication standard interface processing based on the chip select signal XMCS input from terminal TCS1, the serial clock signal MSCLK input from terminal TCK1, and the serial data signal MSDI input from terminal TDI1. If the serial data signal MSDI is a read command for the first detection signal SD1, it outputs the first detection signal SD1 to terminal TDO1. The interface circuit 222 performs SPI communication standard interface processing based on the chip select signal XMCS input from terminal TCS2, the serial clock signal MSCLK input from terminal TCK2, and the serial data signal MSDI input from terminal TDI2. If the serial data signal MSDI is a read command for the second detection signal SD2, it outputs the second detection signal SD2 to terminal TDO2. The first detection signal SD1 output from terminal TDO1 of the first inertial sensor 10 and the second detection signal SD2 output from terminal TDO2 of the second inertial sensor 20 are input to terminal TMDI of the processing unit 30 as serial data signals MSDO, respectively.

[0041] The processing unit 30 receives the first detection signal SD1 output from the first inertial sensor 10 and the second detection signal SD2 output from the second inertial sensor 20, and outputs measurement data based on the first detection signal SD1 and the second detection signal SD2 based on output instruction information input from an external source. Specifically, when the processing unit 30 receives the first data ready signal DRDY1 from terminal TMR1, it outputs a read command for the first detection signal SD1 to the first inertial sensor 10 to read the first detection signal SD1, and performs various calculations on the first detection signal SD1. The processing unit 30 also performs the following operations when it receives the second data ready signal DRDY2 from terminal TMR2: it outputs a read command for the second detection signal SD2 to the second inertial sensor 20, reads the second detection signal SD2, and performs various calculations on the second detection signal SD2.

[0042] For example, the processing unit 30 may perform a temperature correction calculation on the first detection signal SD1 and the second detection signal SD2 based on the temperature signal TMPO output from the temperature sensor 40 and input from the terminal TSEN. The temperature correction calculation is a calculation that corrects the temperature dependence of the first detection signal SD1 and the second detection signal SD2 by increasing or decreasing them according to the temperature within a predetermined temperature range. The temperature sensor 40 may be provided on the first inertial sensor 10 or the second inertial sensor 20.

[0043] Furthermore, the processing unit 30 may perform sensitivity correction calculations, offset correction calculations, alignment correction calculations, etc., on the first detection signal SD1 and the second detection signal SD2. Sensitivity correction calculations are calculations that correct the detection sensitivity of each axis so that it becomes a reference value. Offset correction calculations are calculations that correct the zero point of each axis so that it becomes a reference value. Alignment correction calculations are calculations that correct errors caused by the misalignment between the detection axis of each sensor element and the X, Y, or Z axis of the inertial sensor module 2.

[0044] Furthermore, the processing unit 30 may perform calculations to determine the attitude, velocity, angle, etc., of the inertial sensor module 2 based on the first detection signal SD1 and the second detection signal SD2.

[0045] Furthermore, if the period during which the series of calculations is performed by the processing unit 30 is longer than the period of the first data-ready signal DRDY1 or the period of the second data-ready signal DRDY2, the processing unit 30 may perform a downsampling operation to decimate a portion of the first detection signal SD1 and the second detection signal SD2.

[0046] In this embodiment, the processing unit 30 is electrically connected to the host device 3 via terminals THCS, THCK, THDI, THDO, and THR. The host device 3 is a master controller for the processing unit 30. Each time the processing unit 30 completes a series of calculations on the first detection signal SD1 and the second detection signal SD2, it outputs a data ready signal DRDY from terminal THR to the host device 3 to indicate that the measurement data is ready. Each time the host device 3 receives the data ready signal DRDY from terminal THR, it outputs a chip select signal XHCS, a serial clock signal HSCLK, and a serial data signal HSDI, which is a read command for the measurement data as output instruction information, to the processing unit 30, in accordance with the SPI communication standard. Based on the chip select signal XHCS input from terminal THCS, the serial clock signal HSCLK input from terminal THCK, and the serial data signal HSDI input from terminal THDI, the processing unit 30 performs interface processing according to the SPI communication standard and outputs the measurement data to terminal THDO. The measurement data output from the THDO terminal of the processing unit 30 is input to the host device 3 as a serial data signal HSDO. However, the processing unit 30 may perform interface processing such as the I2C communication standard, a communication standard that is an evolution of SPI or I2C, or a communication standard that is an improved or modified version of a part of the SPI or I2C standard.

[0047] Furthermore, in this embodiment, the processing unit 30 outputs measurement data in a format corresponding to the output format selection information input from an external source. Specifically, when the output format selection information is information for selecting a first format, the processing unit 30 outputs measurement data in the first format based on the output instruction information. The measurement data in the first format includes first axis first measurement data based on the detection signal of the first axis included in the first detection signal SD1, second axis measurement data based on the detection signal of the second axis included in the first detection signal SD1, third axis measurement data based on the detection signal of the third axis included in the first detection signal SD1, and included in the second detection signal SD2. Includes first axis second measurement data based on the detection signal of the first axis.

[0048] Furthermore, when the output format selection information is information for selecting the second format, the processing unit 30 outputs measurement data in the second format based on the output instruction information. The measurement data in the second format includes first axis second measurement data based on the detection signal of the first axis included in the second detection signal SD2, second axis measurement data based on the detection signal of the second axis included in the first detection signal SD1, and third axis measurement data based on the detection signal of the third axis included in the first detection signal SD1.

[0049] Furthermore, when the output format selection information is information for selecting the third format, the processing unit 30 outputs measurement data in the third format based on the output instruction information. The measurement data in the third format includes first axis first measurement data based on the detection signal of the first axis included in the first detection signal SD1, second axis measurement data based on the detection signal of the second axis included in the first detection signal SD1, and third axis measurement data based on the detection signal of the third axis included in the first detection signal SD1.

[0050] The host device 3 outputs a chip select signal XHCS, a serial clock signal HSCLK, and a serial data signal HSDI, which is a measurement data format selection command as output format selection information, to the processing unit 30. Based on the chip select signal XHCS input from terminal THCS, the serial clock signal HSCLK input from terminal THCK, and the serial data signal HSDI input from terminal THDI, the processing unit 30 sets the format selected by the measurement data format selection command in a format selection register (not shown). When a measurement data read command is input from terminal THDI, the processing unit 30 refers to the format selection register, selects at least a portion of the various data obtained by a series of calculations, and generates measurement data in the format set in the format selection register. The processing unit 30 then outputs the generated measurement data from terminal THDI.

[0051] Furthermore, if the timing and period of the output of the first data-ready signal DRDY1 from the first inertial sensor 10 do not match the timing and period of the output of the second data-ready signal DRDY2 from the second inertial sensor 20, the detection times of the first detection signal SD1 and the second detection signal SD2 acquired by the processing unit 30 will not match. Therefore, the processing unit 30 calculates first interpolation data for a predetermined time using the first detection signal SD1 at least two times. Each of these at least two times is the time when the first data-ready signal DRDY1 was input at least twice in the most recent period. The processing unit 30 also calculates second interpolation data for the same predetermined time using the second detection signal SD2 at least two times. Each of these at least two times is the time when the second data-ready signal DRDY2 was input at least twice in the most recent period. For example, the processing unit 30 may approximate the first detection signals SD1 from the two most recently acquired time points with a linear equation and calculate the first interpolated data for a predetermined time point by linear interpolation, and approximate the second detection signals SD2 from the two most recently acquired time points with a linear equation and calculate the second interpolated data for the same predetermined time point by linear interpolation. Alternatively, the processing unit 30 may approximate the first detection signals SD1 from three or more most recently acquired time points with a polynomial of degree two or higher and calculate the first interpolated data for a predetermined time point by nonlinear interpolation, and approximate the second detection signals SD2 from three most recently acquired time points with a polynomial of degree two or higher and calculate the second interpolated data for the same predetermined time point by nonlinear interpolation.

[0052] In this way, the processing unit 30 calculates the first and second complementary data for the same time, performs the aforementioned series of calculations on the first and second complementary data, and outputs a data ready signal DRDY when the calculations are complete. Then, based on the command to read the measurement data from the host device 3, the processing unit 30 selects the format. The device outputs measurement data based on the first and second complementary data in the format set on the device.

[0053] 1-3. Processing Unit Configuration Next, the specific configuration of the processing unit 30 will be described. Figure 6 is a diagram showing an example of the configuration of the processing unit 30. As shown in Figure 6, the processing unit 30 includes a digital interface circuit 31, a processing circuit 32, and a host interface circuit 33.

[0054] The digital interface circuit 31 is a circuit that performs interface processing with the first inertial sensor 10 and the second inertial sensor 20. That is, the digital interface circuit 31 performs master interface processing with interface circuits 172 and 222. The digital interface circuit 31 is connected to the digital interface bus BS via terminals TMCS, TMCK, TMDO, and TMDI. In this embodiment, the digital interface circuit 31 performs interface processing for the SPI communication standard, similar to interface circuits 172 and 222. However, the digital interface circuit 31 may also perform interface processing for the I2C communication standard, a communication standard developed from SPI or I2C, or a communication standard that is an improved or modified version of a part of the SPI or I2C standard. The digital interface bus BS and the digital interface circuit 31 may be provided in common with the first inertial sensor 10 and the second inertial sensor 20, or they may be provided for the first inertial sensor 10 and the second inertial sensor 20 respectively.

[0055] The host interface circuit 33 is a circuit that performs interface processing with the host device 3. That is, the host interface circuit 33 performs interface processing with the host device 3 as a slave. The host interface circuit 33 performs interface processing with the host device 3 using the SPI communication standard via terminals THCS, THCK, THDO, and THDI. However, the host interface circuit 33 may also perform interface processing using the I2C communication standard, a communication standard that is an evolution of SPI or I2C, or a communication standard that is an improved or modified version of a part of the SPI or I2C standard.

[0056] The processing circuit 32 performs control processing for the digital interface circuit 31 and the host interface circuit 33, as well as various calculation processes. The processing circuit 32 includes a register section 321, a detection signal acquisition circuit 322, an calculation circuit 323, and a measurement data generation circuit 324. The processing circuit 32 may also perform control processing and calculation processing by executing a program stored in a memory unit (not shown).

[0057] The register section 321 includes various registers, such as the format selection register mentioned above.

[0058] Each time the first data ready signal DRDY1 is input from terminal TMR1, the detection signal acquisition circuit 322 outputs a read command for the first detection signal SD1 to the first inertial sensor 10 via the digital interface circuit 31, and acquires the first detection signal SD1 output from the first inertial sensor 10 via the digital interface circuit 31. Also, each time the second data ready signal DRDY2 is input from terminal TMR2, the detection signal acquisition circuit 322 outputs a read command for the second detection signal SD2 to the second inertial sensor 20 via the digital interface circuit 31, and acquires the second detection signal SD2 output from the second inertial sensor 20 via the digital interface circuit 31.

[0059] The calculation circuit 323 receives the first detection signal SD1 and the second detection signal acquired by the detection signal acquisition circuit 322. Various calculations are performed on the output signal SD2. For example, the calculation circuit 323 performs temperature correction calculations on the detection signals of the first axis, second axis, third axis, fourth axis, fifth axis, and sixth axis, which are included in the first detection signal SD1, based on the temperature signal TMPO input from terminal TSEN. Similarly, the calculation circuit 323 performs temperature correction calculations on the detection signal of the first axis, which is included in the second detection signal SD2, based on the temperature signal TMPO input from terminal TSEN. In addition, the calculation circuit 323 performs sensitivity correction calculations, offset correction calculations, alignment correction calculations, etc. on the detection signals of the first axis, second axis, third axis, fourth axis, fifth axis, and sixth axis, which are included in the first detection signal SD1. Similarly, the calculation circuit 323 performs sensitivity correction calculations, offset correction calculations, alignment correction calculations, etc. on the detection signal of the first axis, which is included in the second detection signal SD2. Furthermore, the calculation circuit 323 may omit some of the temperature correction calculation, sensitivity correction calculation, offset correction calculation, and alignment correction calculation, or it may perform other correction calculations.

[0060] The calculation circuit 323 calculates, through these series of calculations, the first measurement data of the first axis based on the detection signal of the first axis included in the first detection signal SD1, the second measurement data of the second axis based on the detection signal of the second axis included in the first detection signal SD1, the third measurement data of the third axis based on the detection signal of the third axis included in the first detection signal SD1, the fourth measurement data of the fourth axis based on the detection signal of the fourth axis included in the first detection signal SD1, the fifth measurement data of the fifth axis based on the detection signal of the fifth axis included in the first detection signal SD1, the sixth measurement data of the sixth axis based on the detection signal of the sixth axis included in the first detection signal SD1, and the second measurement data of the first axis based on the detection signal of the first axis included in the second detection signal SD2.

[0061] Furthermore, if the period during which the series of calculations is performed by the arithmetic circuit 323 is longer than the period of the first data-ready signal DRDY1 or the second data-ready signal DRDY2, it performs a downsampling operation to decimate a portion of the first detection signal SD1 and the second detection signal SD2, and then performs various calculation processes.

[0062] Furthermore, the calculation circuit 323 may perform calculations to calculate at least one of the attitude, velocity, and angle of the inertial sensor module 2 based on the first detection signal SD1 and the second detection signal SD2. The attitude may be expressed in terms of roll, pitch, and yaw, or in terms of Euler angles or quaternions. For example, suppose the first sensor element 11, the second sensor element 12, the third sensor element 13, and the sensor element 21 each detect angular velocity, and the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16 each detect acceleration. In this case, the calculation circuit 323 calculates the attitude based on the first axis first measurement data or the first axis second measurement data, the second axis measurement data, and the third axis measurement data. The calculation circuit 323 also integrates the fourth axis measurement data, the fifth axis measurement data, and the sixth axis measurement data, respectively, to calculate the velocity in the fourth axis direction, the fifth axis direction, and the sixth axis direction. Furthermore, the calculation circuit 323 integrates the first measurement data of the first axis, the second measurement data of the first axis, the second axis measurement data, and the third axis measurement data, respectively, to calculate the angle around the first axis, the angle around the second axis, and the angle around the third axis.

[0063] Once the calculations are complete, the arithmetic circuit 323 outputs a data-ready signal DRDY to the host device 3 via terminal THR.

[0064] If the detection time of the first detection signal SD1 and the detection time of the second detection signal SD2 do not coincide, the calculation circuit 323 calculates first interpolation data for a predetermined time using the first detection signal SD1 at least two times, and calculates second interpolation data for the same predetermined time using the second detection signal SD2 at at least two times. The first interpolation data includes interpolation data for the detection signals of the first axis, second axis, third axis, fourth axis, fifth axis, and sixth axis, which are included in the first detection signal SD1. The second interpolation data is: The second detection signal SD2 includes interpolation data for the detection signal of the first axis. The calculation circuit 323 then performs the aforementioned series of calculations on the first interpolation data and second interpolation data calculated for the same time to calculate the first measurement data for the first axis, the second measurement data for the second axis, the third measurement data for the third axis, the fourth measurement data for the fourth axis, the fifth measurement data for the fifth axis, the sixth measurement data for the sixth axis, and the second measurement data for the first axis.

[0065] The first measurement data for the first axis, the second measurement data for the second axis, the third measurement data for the fourth axis, the fifth measurement data for the fifth axis, the sixth axis measurement data, and the second measurement data for the first axis are each stored in different registers of the register unit 321. In addition, the attitude, velocity, and angle data of the inertial sensor module 2 are also each stored in different registers of the register unit 321. The host device 3 can read the first measurement data for the first axis, the second measurement data for the second axis, the third measurement data for the fourth axis, the fifth axis measurement data for the fifth axis, the sixth axis measurement data, and the second measurement data for the first axis by specifying different addresses, or it can read the measurement data in the format set in the format selection register.

[0066] When a command to read measurement data from the host device 3 is input via the host interface circuit 33, the measurement data generation circuit 324 refers to the format selection register included in the register section 321 and generates measurement data in a format corresponding to the setting value of the format selection register. The measurement data generation circuit 324 then outputs the generated measurement data to the host device 3 via the host interface circuit 33.

[0067] Figure 7 shows an example of a selectable measurement data format in the first embodiment.

[0068] In the first embodiment, when the first format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the first format when a read command for the measurement data is input. As shown in FIG. 7, the measurement data in the first format includes first-axis first measurement data G based on the detection signal of the first axis included in the first detection signal SD1 Z1 , second-axis measurement data G based on the detection signal of the second axis included in the first detection signal SD1 X1 , third-axis measurement data G based on the detection signal of the third axis included in the first detection signal SD1 Y1 , and first-axis second measurement data G based on the detection signal of the first axis included in the second detection signal SD2 Z2 . Further, in the example of FIG. 7, the measurement data in the first format includes fourth-axis measurement data A based on the detection signal of the fourth axis included in the first detection signal SD1 Z1 , fifth-axis measurement data A based on the detection signal of the fifth axis included in the first detection signal SD1 X1 , and sixth-axis measurement data A based on the detection signal of the sixth axis included in the first detection signal SD1 Y1 .

[0069] Also, in the first embodiment, when the second format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the second format when a read command for the measurement data is input. As shown in FIG. 7, the measurement data in the second format includes first-axis second measurement data G based on the detection signal of the first axis included in the second detection signal SD2 Z2 , second-axis measurement data G based on the detection signal of the second axis included in the first detection signal SD1 X1 , and third-axis measurement data G based on the detection signal of the third axis included in the first detection signal SD1 Y1 . Further, in the example of FIG. 7, the measurement data in the second format includes fourth-axis measurement data A based on the detection signal of the fourth axis included in the first detection signal SD1 Z1 , fifth-axis measurement data A based on the detection signal of the fifth axis included in the first detection signal SD1 X1 , and sixth-axis measurement data A based on the detection signal of the sixth axis included in the first detection signal SD1 Y1, and temperature data TP based on temperature signal TMPO.

[0070] Furthermore, in the first embodiment, the measurement data generation circuit 324 receives a command to read measurement data when the third format is set in the format selection register. The measurement data in the third format is output. As shown in Figure 7, the measurement data in the third format is the first measurement data G of the first axis based on the detection signal of the first axis included in the first detection signal SD1. Z1 , Second axis measurement data G based on the detection signal of the second axis included in the first detection signal SD1 X1 , and third-axis measurement data G based on the third-axis detection signal included in the first detection signal SD1. Y1 This includes. Furthermore, in the example in Figure 7, the measurement data in the third format is the fourth axis measurement data A, which is based on the fourth axis detection signal included in the first detection signal SD1. Z1 , Fifth axis measurement data A based on the fifth axis detection signal included in the first detection signal SD1 X1 , and 6th axis measurement data A based on the 6th axis detection signal included in the 1st detection signal SD1. Y1 , and temperature data TP based on temperature signal TMPO.

[0071] In the example in Figure 7, the first measurement data G of the first axis. Z1 and first axis second measurement data G Z2 These are both Z-axis angular velocity data. Also, the second axis measurement data G X1 This is the X-axis angular velocity data, and the third-axis measurement data G Y1 This is the Y-axis angular velocity data. Also, the 4th axis measurement data A Z1 This is Z-axis acceleration data, and fifth-axis measurement data A X1 This is X-axis acceleration data, and 6th axis measurement data A Y1 This is Y-axis acceleration data.

[0072] Here, in the measurement data of the first format, the first data is the second axis measurement data G X1 The second data is the third-axis measurement data G. Y1The third data is the first axis second measurement data G. Z2 Furthermore, in the measurement data of the second format, the first data is the second axis measurement data G X1 The second data is the third-axis measurement data G. Y1 The third data is the first axis second measurement data G. Z2 Furthermore, in the third format of measurement data, the first data is the second axis measurement data G X1 The second data is the third-axis measurement data G. Y1 The third data is the first measurement data G of the first axis. Z1 That is, the second axis measurement data G included in the measurement data of the first format X1 , Second axis measurement data G included in the measurement data of the second format X1 and the second axis measurement data G included in the measurement data of the third format X1 The arrangement is the same. Also, the third-axis measurement data G included in the measurement data of the first format Y1 , the third-axis measurement data G included in the measurement data of the second format Y1 and the third-axis measurement data G included in the measurement data of the third format Y1 The arrangement is the same. Also, the first axis second measurement data G included in the first format measurement data Z2 , the second measurement data of the first axis G included in the measurement data of the second format Z2 and the first measurement data G of the first axis included in the measurement data of the third format Z1 The arrangement is the same. In other words, in all three formats of measurement data—first format, second format, and third format—the first data point is the measurement data for the second axis, the second data point is the measurement data for the third axis, and the third data point is the measurement data for the first axis. Therefore, regardless of whether the output is the first format, second format, or third format of measurement data, the host device 3 can perform calculations using the measurement data for the first axis, second axis, and third axis in the same way.

[0073] Similarly, in all three formats of measurement data (first format, second format, and third format), the fourth data is the fifth axis measurement data A. X1 The fifth data point is the 6th axis measurement data A. Y1 The sixth data point is the 4th axis measurement data A. Z1 Therefore, regardless of whether the measurement data is in the first format, the second format, or the third format, the host device 3 will output the fourth axis measurement data A. Z1 , 5th axis measurement data A X1 and 6-axis measurement data A Y1 Operations using this can be performed in a similar manner.

[0074] Next, we will explain a specific example of switching the format of the measurement data that the host device 3 outputs to the inertial sensor module 2, using the example in Figure 7.

[0075] The detection accuracy of the second inertial sensor 20 is set to be higher than that of the first inertial sensor 10. For example, the sensor element 21 of the second inertial sensor 20 is an element made of quartz, whereas the first sensor element 11, second sensor element 12, and third sensor element 13 of the first inertial sensor 10 are elements formed from a silicon substrate using MEMS technology. The second inertial sensor 20, having such a sensor element 21, has high frequency-temperature characteristics and frequency stability, and low noise and jitter, and therefore has higher detection accuracy than the first inertial sensor 10, which has the first sensor element 11, second sensor element 12, and third sensor element 13, although it is more expensive. Therefore, when high accuracy is required for detecting the physical quantity of the first axis, basically, the measurement data of the first axis is the first axis second measurement data G Z2 This is used.

[0076] On the other hand, due to differences in material and structure between the sensor element 21 and the first sensor element 11, the data range in which the linearity of the output to the input is satisfied is the first measurement data G of the first axis. Z1 The first axis second measurement data GZ2 It may be wider than that. Therefore, the first axis second measurement data G Z2 In the first input range where linearity is satisfied, the first axis second measurement data G Z2 The first axis first measurement data G Z1 Higher accuracy than the first axis second measurement data G Z2 For the second input range where linearity is not satisfied, the first measurement data G of the first axis Z1 The first axis second measurement data G Z2 It may be more accurate than that.

[0077] In such a case, when the host device 3 is causing the inertial sensor module 2 to output measurement data in the first format, the first axis second measurement data G Z2 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 The calculation is performed using the first axis first measurement data G Z1 Based on the value, the host device 3 determines whether the physical quantity applied to the first axis falls within the first input range or the second input range. If the physical quantity applied to the first axis falls within the first input range, the host device 3 leaves the setting of the format selection register unchanged in the first format. If the physical quantity applied to the first axis falls within the second input range, the host device 3 changes the setting of the format selection register to the third format. Furthermore, when the host device 3 is causing the inertial sensor module 2 to output measurement data in the third format, the first measurement data G for the first axis Z1 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 The calculation is performed using the first axis first measurement data G Z1Based on the value, the host device 3 determines whether the physical quantity applied to the first axis falls within the first input range or the second input range. Then, if the physical quantity applied to the first axis falls within the second input range, the host device 3 leaves the setting of the format selection register unchanged at the third format, and if the physical quantity applied to the first axis falls within the first input range, it changes the setting of the format selection register to the first format. In this way, the host device 3 selects the first measurement data G of the first axis, which has a wider range of linearity. Z1 By more accurately determining whether the physical quantity applied to the first axis falls within the first input range or the second input range based on the value of [value], and switching between the first and third formats, the accuracy of the calculation can be improved regardless of the range of the physical quantity applied to the first axis.

[0078] Furthermore, in the example shown in Figure 7, we will describe another specific example of how the host device 3 switches the format of the measurement data that it outputs to the inertial sensor module 2.

[0079] When the temperature is within the first temperature range, the second measurement data G of the first axis is obtained. Z2 The first axis first measurement data G Z1 It is more accurate, and when the temperature is outside the first temperature range, the first measurement data G of the first axis is obtained. Z1 The first axis second measurement data G Z2 In some cases, the accuracy may be higher. In such cases, when the host device 3 is causing the inertial sensor module 2 to output measurement data in the second format, the first axis second measurement data G Z2 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 The calculation is performed using the following, and based on the value of the temperature data TP, it is determined whether the temperature falls within the first temperature range or the second temperature range. When the temperature falls within the first temperature range, the host device 3 does not change the setting of the format selection register to the second format, and when the temperature falls within the second temperature range, it changes the setting of the format selection register to the third format. Also, when the host device 3 is causing the inertial sensor module 2 to output measurement data in the third format, the first axis first measurement data G Z1 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 The host device 3 performs calculations using the temperature data TP and determines whether the temperature falls within the first or second temperature range. If the temperature falls within the second temperature range, the host device 3 leaves the setting of the format selection register unchanged to the third format. If the temperature falls within the first temperature range, the host device 3 changes the setting of the format selection register to the second format. In this way, the host device 3 can improve the accuracy of calculations regardless of the temperature range by determining whether the temperature falls within the first or second temperature range based on the value of the temperature data TP and switching between the second and third formats.

[0080] 1-4. Effects As described above, according to the inertial measurement system 1 of the first embodiment, the format of the measurement data output from the inertial sensor module 2 is selected according to the output format selection information input from the host device 3, so the format of the measurement data can be changed from the host device 3.

[0081] Furthermore, according to the inertial measurement system 1 of the first embodiment, the host device 3 can cause the inertial sensor module 2 to output measurement data in the first format and perform calculations based on the first axis second measurement data, second axis measurement data, and third axis measurement data.

[0082] Furthermore, according to the inertial measurement system 1 of the first embodiment, the host device 3 can have the inertial sensor module 2 output measurement data in a second format and perform calculations based on the first axis second measurement data, second axis measurement data and third axis measurement data, or it can have the inertial sensor module 2 output measurement data in a third format and perform calculations based on the first axis first measurement data, second axis measurement data and third axis measurement data.

[0083] Furthermore, according to the inertial measurement system 1 of the first embodiment, the arrangement of the measurement data for the first axis, the measurement data for the second axis, and the measurement data for the third axis is the same regardless of whether the measurement data is in the first format, the second format, or the third format output from the inertial sensor module 2. Therefore, the host device 3 can perform calculations using the measurement data for the first axis, the measurement data for the second axis, and the measurement data for the third axis in the same way, regardless of whether the measurement data is in the first format, the second format, or the third format.

[0084] Furthermore, according to the inertial measurement system 1 of the first embodiment, the inertial sensor module 2 can output measurement data including first and second complementary data with synchronized timings, even if the detection timing and detection period differ between the first inertial sensor 10 and the second inertial sensor 20. Therefore, the host device 3 can perform correct calculations based on the first and second complementary data.

[0085] 2. Second Embodiment In the following description of the inertial measurement system of the second embodiment, the same reference numerals are used for components similar to those in the first embodiment, and explanations that overlap with those of the first embodiment are omitted or simplified. The main points to be described are the differences from the first embodiment.

[0086] The structure of the inertial sensor module 2 in the second embodiment is the same as in Figures 1 to 4, so its illustration is omitted. Also, the functional configuration of the inertial sensor module 2 in the second embodiment is the same as in Figure 5, so its illustration is omitted. Also, the functional configuration of the processing unit 30 in the second embodiment is the same as in Figure 6, so its illustration is omitted. In the inertial measurement system 1 of the second embodiment, a fourth format is added as a selectable format for the measurement data output from the processing unit 30 of the inertial sensor module 2.

[0087] In the second embodiment, the processing unit 30 calculates, similar to the first embodiment, first measurement data of the first axis obtained by correcting the detection signal of the first axis included in the first detection signal SD1, second measurement data of the second axis obtained by correcting the detection signal of the second axis included in the first detection signal SD1, third measurement data of the third axis obtained by correcting the detection signal of the third axis included in the first detection signal SD1, and second measurement data of the first axis obtained by correcting the detection signal of the first axis included in the second detection signal SD2. Similarly, the processing unit 30 calculates fourth-axis measurement data obtained by correcting the detection signal of the fourth axis included in the first detection signal SD1, fifth-axis measurement data obtained by correcting the detection signal of the fifth axis included in the first detection signal SD1, and sixth-axis measurement data obtained by correcting the detection signal of the sixth axis included in the first detection signal SD1.

[0088] Then, when the output format selection information is information to select the fourth format, the processing unit 30 outputs measurement data in the fourth format based on the output instruction information. That is, when the fourth format is set in the format selection register, the measurement data generation circuit 324 included in the processing unit 30 generates measurement data in the fourth format when a command to read measurement data from the host device 3 is input via the host interface circuit 33, and outputs the generated measurement data to the host device 3 via the host interface circuit 33.

[0089] Figure 8 shows an example of a selectable measurement data format in the second embodiment.

[0090] In the second embodiment, when the first format is set in the format selection register, the measurement data generation circuit 324 outputs the measurement data in the first format when a read command for the measurement data is input. Further, when the second format is set in the format selection register, the measurement data generation circuit 324 outputs the measurement data in the second format when a read command for the measurement data is input. Further, when the third format is set in the format selection register, the measurement data generation circuit 324 outputs the measurement data in the third format when a read command for the measurement data is input. As shown in FIG. 8, the measurement data in the first format, the measurement data in the second format, and the measurement data in the third format are the same as those in FIG. 7, and thus the description thereof is omitted.

[0091] Furthermore, in the second embodiment, when the fourth format is set in the format selection register, the measurement data generation circuit 324 outputs the measurement data in the fourth format when a read command for the measurement data is input. In the example of FIG. 8, the measurement data in the fourth format includes the first-axis first measurement data G Z1 , the second-axis measurement data G X1 , the third-axis measurement data G Y1 , the first-axis second measurement data G Z2 , the first-axis first detection data G Z1 ' which is the detection signal of the first axis included in the first detection signal SD1, the second-axis detection data G X1 ' which is the detection signal of the second axis included in the first detection signal SD1, the third-axis detection data G Y1 ' which is the detection signal of the third axis included in the first detection signal SD1, and the first-axis second detection data G Z2 ' which is the detection signal of the first axis included in the second detection signal SD2. Further, in the example of FIG. 8, the measurement data in the fourth format includes the fourth-axis measurement data A Z1 , the fifth-axis measurement data A X1 , the sixth-axis measurement data A Y1 , the fourth-axis detection data A Z1 ' which is the detection signal of the fourth axis included in the first detection signal SD1, the fifth-axis detection data AX1 ’, the sixth-axis detection data A, which is the detection signal of the sixth axis included in the first detection signal SD1 Y1 ’ is included.

[0092] In the example of FIG. 8, the first-axis first measurement data G Z1 , the first-axis second measurement data G Z2 , the first-axis first detection data G Z1 ’ and the first-axis second detection data G Z2 ’ are both Z-axis angular velocity data. Also, the second-axis measurement data G X1 and the second-axis detection data G X1 ’ are X-axis angular velocity data, and the third-axis measurement data G Y1 and the third-axis detection data G Y1 ’ are Y-axis angular velocity data. Also, the fourth-axis measurement data A Z1 and the fourth-axis detection data A Z1 ’ are Z-axis acceleration data, and the fifth-axis measurement data A X1 and the fifth-axis detection data A X1 ’ are X-axis acceleration data, and the sixth-axis measurement data A Y1 and the sixth-axis detection data A Y1 ’ are Y-axis acceleration data.

[0093] Here, in any of the measurement data in the first to fourth formats, the first data is the measurement data of the second axis, the second data is the measurement data of the third axis, and the third data is the measurement data of the first axis. Therefore, regardless of which of the measurement data in the first to fourth formats is output, the host device 3 can perform the same operations using the measurement data of the first axis, the measurement data of the second axis, and the measurement data of the third axis. Similarly, in any of the measurement data in the first to fourth formats, the fourth data is the fifth-axis measurement data A X1 , the fifth data is the sixth-axis measurement data A Y1 , and the sixth data is the fourth-axis measurement data A Z1 . Therefore, regardless of which of the measurement data in the first to fourth formats is output, the host device 3 can use the fourth-axis measurement data A Z1, 5th axis measurement data A X1 and 6-axis measurement data A Y1 Operations using this can be performed in a similar manner.

[0094] For example, the host device 3 periodically causes the inertial sensor module 2 to output measurement data in the fourth format, and the first measurement data G of the first axis. Z1 , 2nd axis measurement data G X1 , 3rd axis measurement data G Y1 and first axis second measurement data G Z2 These are the first detection data G for the first axis. Z1 ', Second axis detection data G X1 ', 3rd axis detection data G Y1 'and first axis second detection data G Z2 By comparing it with the first measurement data G of the first axis, Z1 , 2nd axis measurement data G X1 , 3rd axis measurement data G Y1 and first axis second measurement data G Z2 It is possible to determine whether each of these is normal or not. Similarly, the host device 3 can determine whether the fourth axis measurement data A Z1 , 5th axis measurement data A X1 and 6-axis measurement data A Y1 These are the 4th axis detection data A, respectively. Z1 ', 5th axis detection data A X1 'and 6-axis detection data A Y1 By comparing it with ', the 4th axis measurement data A Z1 , 5th axis measurement data A X1 and 6-axis measurement data A Y1 It is possible to determine whether each of these is normal or not.

[0095] The other configurations and functions of the inertial measurement system 1 in the second embodiment are the same as those in the first embodiment, so their description will be omitted.

[0096] The inertial measurement system 1 of the second embodiment described above has the same effects as the inertial measurement system 1 of the first embodiment.

[0097] Furthermore, in the inertial measurement system 1 of the second embodiment, the inertial sensor module 2 can output measurement data including first axis first detection data, first axis first measurement data corrected from the first axis first detection data, second axis detection data, second axis measurement data corrected from the second axis detection data, third axis detection data, third axis measurement data corrected from the third axis detection data, first axis second detection data, and first axis second measurement data corrected from the first axis second detection data. Therefore, the host device 3 can, for example, compare the first axis first measurement data, second axis measurement data, third axis measurement data, and first axis second measurement data with the first axis first detection data, second axis detection data, third axis detection data, and first axis second detection data, respectively, to determine whether the correction processing by the processing device 30 is normal or to evaluate the degree of said correction processing.

[0098] 3. Third Embodiment In the following description of the inertial measurement system of the third embodiment, the same reference numerals are used for components similar to those in the first or second embodiment, and explanations that overlap with those of the first or second embodiment are omitted or simplified. The description will mainly focus on the differences from the first and second embodiments.

[0099] The structure of the inertial sensor module 2 in the third embodiment is the same as in Figures 1 to 4, so its illustration is omitted. Also, the functional configuration of the inertial sensor module 2 in the third embodiment is the same as in Figure 5, so its illustration is omitted. Also, the functional configuration of the processing unit 30 in the third embodiment is the same as in Figure 6, so its illustration is omitted. In the inertial measurement system 1 of the third embodiment, a fifth format and a sixth format are added as selectable formats for the measurement data output from the processing unit 30 of the inertial sensor module 2.

[0100] In the third embodiment, the processing unit 30 calculates, similar to the first and second embodiments, first measurement data of the first axis obtained by correcting the detection signal of the first axis included in the first detection signal SD1, second measurement data of the second axis obtained by correcting the detection signal of the second axis included in the first detection signal SD1, third measurement data of the third axis obtained by correcting the detection signal of the third axis included in the first detection signal SD1, and second measurement data of the first axis obtained by correcting the detection signal of the first axis included in the second detection signal SD2. Similarly, the processing unit 30 calculates fourth-axis measurement data obtained by correcting the detection signal of the fourth axis included in the first detection signal SD1, fifth-axis measurement data obtained by correcting the detection signal of the fifth axis included in the first detection signal SD1, and sixth-axis measurement data obtained by correcting the detection signal of the sixth axis included in the first detection signal SD1.

[0101] Furthermore, in the third embodiment, when the output format selection information is information for selecting the fifth format, the processing unit 30 calculates first inertial data including at least one of the attitude, velocity, and angle of the inertial sensor module 2 based on the detection signal of the first axis included in the second detection signal SD2, the detection signal of the second axis included in the first detection signal SD1, and the detection signal of the third axis included in the first detection signal SD1, and outputs measurement data in the fifth format including the first inertial data based on the output instruction information. The processing unit 30 may further calculate the first inertial data based on the detection signal of the fourth axis included in the first detection signal SD1, the detection signal of the fifth axis included in the first detection signal SD1, and the detection signal of the sixth axis included in the first detection signal SD1.

[0102] Furthermore, in the third embodiment, when the output format selection information is information for selecting the sixth format, the processing unit 30 calculates second inertial data including at least one of the attitude, velocity, and angle of the inertial sensor module 2 based on the detection signal of the first axis included in the first detection signal SD1, the detection signal of the second axis included in the first detection signal SD1, and the detection signal of the third axis included in the first detection signal SD1, and outputs measurement data in the sixth format including the second inertial data based on the output instruction information. The processing unit 30 may further calculate the second inertial data based on the detection signal of the fourth axis included in the first detection signal SD1, the detection signal of the fifth axis included in the first detection signal SD1, and the detection signal of the sixth axis included in the first detection signal SD1.

[0103] For example, if the fifth format is set in the format selection register, the measurement data generation circuit 324 included in the processing unit 30 generates first inertia data based on the first axis second measurement data, second axis measurement data, third axis measurement data, fourth axis measurement data, fifth axis measurement data, and sixth axis measurement data. Then, when a command to read measurement data from the host device 3 is input to the measurement data generation circuit 324 via the host interface circuit 33, it generates measurement data in the fifth format including the first inertia data and outputs the generated measurement data to the host device 3 via the host interface circuit 33. Furthermore, if the sixth format is set in the format selection register, the measurement data generation circuit 324 generates first axis first measurement data, second axis measurement data, third axis measurement data, and Second inertia data is generated based on the 4-axis measurement data, 5-axis measurement data, and 6-axis measurement data. When a command to read measurement data from the host device 3 is input to the measurement data generation circuit 324 via the host interface circuit 33, the circuit generates measurement data in a 6th format, including the second inertia data, and outputs the generated measurement data to the host device 3 via the host interface circuit 33.

[0104] Figure 9 shows an example of a selectable measurement data format in the third embodiment.

[0105] In the third embodiment, if the first format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the first format when a measurement data read command is input. If the second format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the second format when a measurement data read command is input. If the third format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the third format when a measurement data read command is input. If the fourth format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the fourth format when a measurement data read command is input. As shown in Figure 9, the measurement data in the first format, the second format, the third format, and the fourth format are the same as in Figure 8, so their explanation is omitted.

[0106] Furthermore, in the third embodiment, if the fifth format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the fifth format when a measurement data read command is input. In the example in Figure 9, the measurement data in the fifth format is the first axis second measurement data G Z2 , 2nd axis measurement data G X1 , 3rd axis measurement data G Y1 , 4th axis measurement data A Z1 , 5th axis measurement data A X1 , 6th axis measurement data A Y1 and temperature data TP. Furthermore, in the example in Figure 9, the measurement data in the fifth format includes, as first inertial data, roll angle data R1, pitch angle data P1 and second yaw angle data Y2 representing the attitude of the inertial sensor module 2, and first axis second angle data θ representing the angle of the inertial sensor module 2. Z2 , second axis angle data θ X1 and third axis angle data θ Y1This includes: roll angle data R1, pitch angle data P1, and second yaw angle data Y2, and first axis second measurement data G Z2 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 This is posture data calculated based on the following: Also, the first axis and second angle data θ. Z2 , second axis angle data θ X1 and third axis angle data θ Y1 These are the first axis and second measurement data G, respectively. Z2 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 This is the angle data obtained by integrating the curve.

[0107] Furthermore, if the sixth format is set in the format selection register, the measurement data generation circuit 324 outputs measurement data in the sixth format when a command to read measurement data is input. In the example in Figure 9, the measurement data in the sixth format is the first measurement data G of the first axis. Z1 , 2nd axis measurement data G X1 , 3rd axis measurement data G Y1 , 4th axis measurement data A Z1 , 5th axis measurement data A X1 , 6th axis measurement data A Y1 and temperature data TP. Furthermore, in the example in Figure 9, the measurement data in the sixth format includes, as second inertial data, roll angle data R1, pitch angle data P1, and first yaw angle data Y1 representing the attitude of the inertial sensor module 2, and first axis first angle data θ representing the angle of the inertial sensor module 2. Z1 , second axis angle data θ X1 and third axis angle data θ Y1 This includes: roll angle data R1, pitch angle data P1, and first yaw angle data Y1, first axis first measurement data G Z1 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 This is posture data calculated based on the following. Also, the first axis first angle data θ Z1 , second axis angle data θ X1 and third axis angle data θ Y1These are, respectively, the first measurement data G of the first axis. Z1 , 2nd axis measurement data G X1 and 3 Axis measurement data G Y1 This is the angle data obtained by integrating the curve.

[0108] In the example in Figure 9, the first measurement data G of the first axis. Z1 , 1st axis 2nd measurement data G Z2 , First axis first detection data G Z1 'and first axis second detection data G Z2 ' represents Z-axis angular velocity data. Also, the second axis measurement data G X1 and 2-axis detection data G X1 ' represents the X-axis angular velocity data, and the third-axis measurement data G Y1 and 3rd axis detection data G Y1 ' represents the Y-axis angular velocity data. Also, the 4th axis measurement data A Z1 and 4th axis detection data A Z1 ' represents Z-axis acceleration data, and 5th axis measurement data A X1 and 5-axis detection data A X1 ' represents the X-axis acceleration data, and the 6th axis measurement data A Y1 and 6-axis detection data A Y1 ' represents the Y-axis acceleration data.

[0109] In the example in Figure 9, the measurement data in the fifth format and the measurement data in the sixth format include attitude data and angle data, but velocity data may be included together with these, or in place of at least one of them. Velocity data is measured in the fourth axis A Z1 , 5th axis measurement data A X1 and 6-axis measurement data A Y1 The system may also include fourth-axis velocity data, fifth-axis velocity data, and fifth-axis velocity data obtained by integrating each of these.

[0110] Here, in all of the measurement data formats from the first to the sixth format, the first data is the measurement data for the second axis, the second data is the measurement data for the third axis, and the third data is the measurement data for the first axis. Therefore, regardless of which of the measurement data formats from the first to the sixth format is output, the host device 3 can similarly perform calculations using the measurement data for the first axis, the second axis, and the third axis. Similarly, in all of the measurement data formats from the first to the sixth format, the fourth data is the measurement data for the fifth axis A. X1 The fifth data point is the 6th axis measurement data A. Y1 The sixth data point is the 4th axis measurement data A. Z1 Therefore, regardless of which of the measurement data formats from the first to the sixth is output by the host device 3, the 4th axis measurement data A Z1 , 5th axis measurement data A X1 and 6-axis measurement data A Y1 Operations using this can be performed in a similar manner.

[0111] For example, when the host device 3 is causing the inertial sensor module 2 to output measurement data in the fifth format, calculations are performed using roll angle data R1, pitch angle data P1 and second yaw angle data Y2, and the first axis second measurement data G Z2 , 2nd axis measurement data G X1 and 3-axis measurement data G Y1 The host device 3 performs calculations using the following and determines whether the temperature falls within the first or second temperature range based on the value of the temperature data TP. If the temperature falls within the first temperature range, the host device 3 leaves the setting of the format selection register unchanged to the fifth format. If the temperature falls within the second temperature range, the host device 3 changes the setting of the format selection register to the sixth format. Furthermore, when the inertial sensor module 2 is outputting measurement data in the sixth format, the host device 3 performs calculations using the roll angle data R1, pitch angle data P1, and first yaw angle data Y1, as well as the first axis first measurement data G Z1 , 2nd axis measurement data GX1 and 3-axis measurement data G Y1 The host device 3 performs calculations using the format selection register and determines whether the temperature falls within the first or second temperature range based on the value of the temperature data TP. If the temperature falls within the second temperature range, the host device 3 leaves the setting of the format selection register unchanged to the sixth format. If the temperature falls within the first temperature range, the host device 3 changes the setting of the format selection register to the fifth format. In this way, the host device 3 can improve the accuracy of calculations regardless of the temperature range by determining whether the temperature falls within the first or second temperature range based on the value of the temperature data TP and switching between the fifth and sixth formats.

[0112] The other configurations and functions of the inertial measurement system 1 of the third embodiment are the same as those of the first or second embodiment, so their description will be omitted.

[0113] The inertial measurement system 1 of the third embodiment described above has the same effects as the inertial measurement system 1 of the first or second embodiment.

[0114] Furthermore, according to the inertial measurement system 1 of the third embodiment, the host device 3 can perform calculations based on the first inertial data by having the inertial sensor module 2 output measurement data in a fifth format, or it can perform calculations based on the second inertial data by having the inertial sensor module 2 output measurement data in a sixth format.

[0115] 4. Fourth Embodiment In the following description of the inertial measurement system of the fourth embodiment, the same reference numerals are used for components that are the same as those in the first to third embodiments. Descriptions that overlap with those of the first to third embodiments will be omitted or simplified, and the description will mainly focus on aspects that differ from any of the first to third embodiments.

[0116] The structure of the inertial sensor module 2 in the fourth embodiment is the same as in Figures 1 to 4, so its illustration is omitted. Also, the functional configuration of the processing unit 30 in the fourth embodiment is the same as in Figure 6, so its illustration is omitted.

[0117] Figure 10 shows the configuration of the inertial measurement system 1 of the fourth embodiment. As shown in Figure 10, the inertial measurement system 1 of the fourth embodiment comprises an inertial sensor module 2 and a host device 3, and further comprises a monitoring device 4. As shown in Figure 10, the functional configuration of the inertial sensor module 2 in the fourth embodiment is the same as in Figure 5.

[0118] In the fourth embodiment, the processing unit 30 of the inertial sensor module 2 is electrically connected to the host device 3 and the monitoring device 4 via terminals THCS, THCK, THDI, THDO, and THR. The host device 3 and the monitoring device 4 are master controllers for the processing unit 30. Each time the processing unit 30 completes a series of calculations for the first detection signal SD1 and the second detection signal SD2, it outputs a data ready signal DRDY from terminal THR to the host device 3 to indicate that the measurement data is ready. Each time the host device 3 receives the data ready signal DRDY from terminal THR, it outputs a chip select signal XHCS, a serial clock signal HSCLK, and a serial data signal HSDI, which is a command to read the measurement data as output instruction information, to the processing unit 30, in accordance with the SPI communication standard. Based on the chip select signal XHCS input from terminal THCS, the serial clock signal HSCLK input from terminal THCK, and the serial data signal HSDI input from terminal THDI, the processing unit 30 performs interface processing according to the SPI communication standard and outputs the measurement data to terminal THDO. The measurement data output from the THDO terminal of the processing unit 30 is input to the host device 3 and the monitoring device 4 as a serial data signal HSDO. However, the processing unit 30 may perform interface processing such as the I2C communication standard, a communication standard that is an evolution of SPI or I2C, or a communication standard that is an improved or modified version of a part of the SPI or I2C standard.

[0119] The monitoring device 4 monitors the measurement data output from the processing device 30 and transmits output format selection information to the processing device 30 according to the monitoring results. Specifically, the monitoring device 4 monitors the measurement data output from terminal THDO of the processing device 30 and outputs the chip select signal XHCS, the serial clock signal HSCLK, and the serial data signal HSDI, which is a measurement data format selection command as output format selection information according to the monitoring results, to the processing device 30.

[0120] Specifically, the monitoring device 4 periodically selects the aforementioned first format for the processing device 30. The monitoring device 4 outputs output format selection information. The monitoring device 4 then compares the first measurement data of the first axis and the second measurement data of the first axis included in the measurement data of the first format output from the processing device 30, determines whether the second inertial sensor 20 is malfunctioning based on the comparison result, and outputs output format selection information to the processing device 30 according to the determination result. For example, the monitoring device 4 may determine that the second inertial sensor 20 is not malfunctioning if the value of the first measurement data of the first axis fluctuates over a predetermined period, while the value of the second measurement data of the first axis fluctuates in the same way, and determine that the second inertial sensor 20 is malfunctioning if the value of the second measurement data of the first axis hardly changes. Alternatively, the monitoring device 4 estimates the period during which the inertial sensor module 2 is stationary based on the output signals of other sensors (not shown). Furthermore, the monitoring device 4 may determine that the second inertial sensor 20 is not malfunctioning if both the first measurement data of the first axis and the second measurement data of the first axis remain almost unchanged during the period when the inertial sensor module 2 is stationary, or it may determine that the second inertial sensor 20 is malfunctioning if the first measurement data of the first axis remains almost unchanged while the second measurement data of the first axis fluctuates.

[0121] Here, the output format selection information that the monitoring device 4 outputs to the processing device 30 when it determines that the second inertial sensor 20 is not malfunctioning is different from the output format selection information that the monitoring device 4 outputs to the processing device 30 when it determines that the second inertial sensor 20 is malfunctioning. For example, if the monitoring device 4 determines that the second inertial sensor 20 is not malfunctioning, it outputs output format selection information that selects the aforementioned second format to the processing device 30, and if it determines that the second inertial sensor 20 is malfunctioning, it outputs output format selection information that selects the aforementioned third format to the processing device 30.

[0122] Thus, in the fourth embodiment, the host device 3 does not need to monitor for any malfunctions in the second inertial sensor 20 and switch the format of the measurement data output from the processing unit 30. Therefore, the host device 3 can concentrate on calculation processing based on the measurement data, thus simplifying the processing of the host device 3.

[0123] The other configurations and functions of the inertial measurement system 1 of the fourth embodiment are the same as those of any of the first to third embodiments, so their description will be omitted.

[0124] The inertial measurement system 1 of the fourth embodiment described above provides the same effects as the inertial measurement system 1 of the first, second, or third embodiment.

[0125] Furthermore, in the inertial measurement system 1 of the fourth embodiment, the monitoring device 4 can change the format of the measurement data based on the monitoring results of the measurement data output from the inertial sensor module 2. Specifically, the monitoring device 4 can change the format of the measurement data output from the inertial sensor module 2 depending on whether or not the second inertial sensor 20 is faulty. Therefore, the host device 3 can perform calculations based on the measurement data output from the inertial sensor module 2 regardless of whether or not the second inertial sensor 20 is faulty. As a result, the host device 3 can concentrate on calculation processing based on the measurement data, thus simplifying the processing of the host device 3.

[0126] 5. Variations The present invention is not limited to this embodiment, and various modifications can be implemented within the scope of the gist of the present invention.

[0127] For example, in the first embodiment described above, an example was given in which the first to third formats from among multiple formats can be selected as the format of the measurement data output from the inertial sensor module 2, but at least the first format from among the multiple formats The first format may be selectable, and at least one of the second and third formats may be unavailable. Alternatively, at least the second and third formats from a plurality of formats may be selectable, and the first format may be unavailable.

[0128] Furthermore, in the second embodiment described above, an example was given in which the first to fourth formats from among multiple formats can be selected as the format of the measurement data output from the inertial sensor module 2. However, it is also possible that at least the fourth format from among the multiple formats can be selected, and at least one of the first to third formats cannot be selected.

[0129] Furthermore, in the third embodiment described above, an example was given in which the first to sixth formats from among multiple formats can be selected as the format of the measurement data output from the inertial sensor module 2. However, it is also possible that at least the fifth and sixth formats from among the multiple formats can be selected, and at least one of the first to fourth formats cannot be selected.

[0130] Furthermore, in each of the above embodiments, the processing unit 30 selects the format of the measurement data using a format selection command for the measurement data input from terminal THDI as output format selection information. However, the format of the measurement data may also be selected using N-bit control signals input from N terminals as output format selection information. Here, N is an integer of 1 or more, and the number of selectable formats is 2. N-1 +1 or more 2 N The following applies:

[0131] Furthermore, in the first to third embodiments described above, the host device 3 may periodically cause the inertial sensor module 2 to output measurement data in the first format, and, similar to the monitoring device 4 in the fourth embodiment, compare the first axis first measurement data and the first axis second measurement data included in the measurement data in the first format to determine whether or not the sensor element 21 is malfunctioning. If the host device 3 determines that the sensor element 21 is not malfunctioning, it may cause the inertial sensor module 2 to output measurement data in the second format, and if it determines that the sensor element 21 is malfunctioning, it may cause the inertial sensor module 2 to output measurement data in the third format.

[0132] Furthermore, in the embodiments described above, examples were given in which the first sensor element 11, the second sensor element 12, the third sensor element 13, and the sensor element 21 each detect angular velocity, and the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16 each detect acceleration. However, the physical quantities detected by each sensor element are not limited to these examples. For instance, the first sensor element 11, the second sensor element 12, the third sensor element 13, and the sensor element 21 may each detect acceleration, and the fourth sensor element 14, the fifth sensor element 15, and the sixth sensor element 16 may each detect angular velocity.

[0133] Furthermore, in each of the above embodiments, the first inertial sensor 10 is composed of six sensor elements, but it may also be composed of four sensor elements. For example, the first sensor element may detect the first, second, and third axes, the second sensor element may detect the fourth axis, the third sensor element may detect the fifth axis, and the fourth sensor element may detect the sixth axis. In this case, the first sensor element may detect angular velocity in three axes, and the second, third, and fifth sensor elements may each detect acceleration in one axis. Alternatively, for example, the first sensor element may detect the first axis, the second sensor element may detect the second axis, the third sensor element may detect the third axis, and the fourth sensor element may detect the fourth, fifth, and sixth axes. In this case, the first, second, and third sensor elements may each detect angular velocity in one axis, and the fourth sensor element may detect acceleration in three axes.

[0134] Furthermore, in each of the above embodiments, the first inertial sensor 10 is composed of six sensor elements, but it may also be composed of five sensor elements. For example, the first sensor element may detect the first axis, the second sensor element may detect the second axis, the third sensor element may detect the third axis, the fourth sensor element may detect the fourth and fifth axes, and the fifth sensor element may detect the sixth axis. In this case, the first, second, and third sensor elements may each detect the angular velocity of one axis, the fourth sensor element may detect the acceleration of two axes, and the fifth sensor element may detect the acceleration of one axis.

[0135] Furthermore, in each of the above embodiments, the first inertial sensor 10 is composed of six sensor elements, but it may also be composed of two sensor elements. For example, the first sensor element may detect the first, second, and third axes, and the second sensor element may detect the fourth, fifth, and sixth axes. In this case, the first sensor element may detect the angular velocity of the three axes, and the second sensor element may detect the acceleration of the three axes.

[0136] Furthermore, in each of the above embodiments, the inertial sensor module 2 is equipped with two inertial sensors, the first inertial sensor 10 and the second inertial sensor 20, but it may be equipped with three or more inertial sensors. For example, as shown in Figure 11, in addition to the first inertial sensor 10 and the second inertial sensor 20, the inertial sensor module 2 may further be equipped with a third inertial sensor 91 for detecting a physical quantity of the second axis and a fourth inertial sensor 92 for detecting a physical quantity of the third axis. For example, the first inertial sensor 10 is a silicon MEMS sensor, and the second inertial sensor 20, the third inertial sensor 91 and the fourth inertial sensor 92 may each be quartz sensors. In this case, for example, the processing unit 30 generates first axis first measurement data, second axis first measurement data and third axis first measurement data based on the first detection signal SD1 output from the first inertial sensor 10, first axis second measurement data based on the second detection signal SD2 output from the second inertial sensor 20, second axis second measurement data based on the third detection signal output from the third inertial sensor 91, and second axis second measurement data based on the fourth detection signal output from the fourth inertial sensor 92. The processing unit 30 may then output measurement data including first axis first measurement data, second axis first measurement data and third axis first measurement data, or measurement data including first axis second measurement data, second axis second measurement data and third axis second measurement data, based on the output format selection information.

[0137] Furthermore, in each of the above embodiments, the first inertial sensor 10 detects physical quantities in 6 axes, but it may also detect physical quantities in 1, 2, 3, 4, 5, or 7 or more axes. Also, in each of the above embodiments, the second inertial sensor 20 detects physical quantities in 1 axis, but it may also detect physical quantities in 2 or more axes. In addition, the first inertial sensor 10 and the second inertial sensor 20 may be sensors with the same structure or sensors with equivalent detection accuracy. For example, as shown in Figure 12, the first inertial sensor 10 and the second inertial sensor 20 may each be silicon MEMS sensors that detect physical quantities in 6 axes. In this case, for example, the processing unit 30 calculates the first data for the nth axis based on the first detection signal SD1 output from the first inertial sensor 10, and calculates the second data for the nth axis based on the second detection signal SD2 output from the second inertial sensor 20. n is an integer between 1 and 6. Furthermore, the processing unit 30 calculates nth-axis averaged measurement data based on data obtained by averaging the detection signal of the nth axis included in the first detection signal SD1 output from the first inertial sensor 10 and the detection signal of the nth axis included in the second detection signal SD2 output from the second inertial sensor 20.The processing unit 30 may then output measurement data including first-axis first measurement data to sixth-axis first measurement data, measurement data including first-axis second measurement data to sixth-axis second measurement data, or measurement data including first-axis averaged measurement data to sixth-axis averaged measurement data, based on the output format selection information.

[0138] Furthermore, in each of the above embodiments, the first inertial sensor 10 is a silicon sensor with relatively low detection accuracy. The example given is that the first inertial sensor is a MEMS sensor and the second inertial sensor 20 is a quartz sensor with relatively high detection accuracy, but it is not limited to this. For example, the first inertial sensor 10 may be a silicon MEMS sensor with relatively low detection accuracy, and the second inertial sensor 20 may be a FOG sensor with relatively high detection accuracy. FOG stands for Fiber Optic Gyroscope. Alternatively, the first inertial sensor 10 may be a sensor with relatively high detection accuracy, and the second inertial sensor 20 may be a sensor with relatively low detection accuracy, or the detection accuracy of the first inertial sensor 10 and the detection accuracy of the second inertial sensor 20 may be the same.

[0139] Furthermore, in the first and second embodiments described above, examples were given in which the processing unit 30 of the inertial sensor module 2 calculates the attitude, velocity, angle, etc. of the inertial sensor module 2. However, a device other than the processing unit 30 may also calculate the attitude, velocity, angle, etc. of the inertial sensor module 2. For example, the host device 3 may calculate the attitude, velocity, angle, etc. of the inertial sensor module 2.

[0140] The embodiments and variations described above are examples only and are not limited thereto. For example, each embodiment and each variation can be combined as appropriate.

[0141] The present invention includes configurations substantially identical to those described in the embodiments, for example, configurations with the same function, method, and results, or configurations with the same purpose and effect. Furthermore, the present invention includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. Furthermore, the present invention includes configurations that produce the same effects or achieve the same purpose as those described in the embodiments. Finally, the present invention includes configurations that add known technology to the configurations described in the embodiments.

[0142] The following can be derived from the embodiments and modifications described above.

[0143] One embodiment of an inertial sensor module is: First inertial sensor and, The second inertial sensor, A processing device that receives a first detection signal output from the first inertial sensor and a second detection signal output from the second inertial sensor, and outputs measurement data based on the first detection signal and the second detection signal based on output instruction information input from an external source, Equipped with, The processing device outputs the measurement data in a format corresponding to the output format selection information input from an external source.

[0144] With this inertial sensor module, the format of the measurement data output based on output instruction information input from an external source is selected according to output format selection information input from an external source, so the format of the measurement data can be changed from an external source.

[0145] In one embodiment of the inertial sensor module, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, When the output format selection information is information for selecting a first format, the processing device outputs the measurement data in the first format based on the output instruction information. The measurement data in the first format includes first axis first measurement data based on the detection signal of the first axis included in the first detection signal, second axis measurement data based on the detection signal of the second axis included in the first detection signal, third axis measurement data based on the detection signal of the third axis included in the first detection signal, and based on the detection signal of the first axis included in the second detection signal. The data may include the second measurement data for the first axis.

[0146] According to this inertial sensor module, an external device can perform calculations based on the first-axis second measurement data, second-axis measurement data, and third-axis measurement data included in the first-format measurement data.

[0147] Furthermore, this inertial sensor module allows an external device to compare the first measurement data of the first axis and the second measurement data of the first axis, which are included in the measurement data of the first format, to determine whether or not there is a malfunction in the first inertial sensor or the second inertial sensor.

[0148] In one embodiment of the inertial sensor module, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, When the output format selection information is information to select a second format, the processing device outputs the measurement data in the second format based on the output instruction information, and when the output format selection information is information to select a third format, it outputs the measurement data in the third format based on the output instruction information. The measurement data in the second format includes first axis second measurement data based on the first axis detection signal included in the second detection signal, second axis measurement data based on the second axis detection signal included in the first detection signal, and third axis measurement data based on the third axis detection signal included in the first detection signal. The measurement data in the third format may include first axis first measurement data, second axis measurement data, and third axis measurement data based on the detection signal of the first axis included in the first detection signal.

[0149] According to this inertial sensor module, an external device can perform calculations based on the first axis second measurement data, second axis measurement data, and third axis measurement data included in the second format measurement data, and can also perform calculations based on the first axis first measurement data, second axis measurement data, and third axis measurement data included in the third format measurement data.

[0150] In one embodiment of the inertial sensor module, When the output format selection information is information to select a second format, the processing device outputs the measurement data in the second format based on the output instruction information, and when the output format selection information is information to select a third format, it outputs the measurement data in the third format based on the output instruction information. The measurement data in the second format includes the first axis second measurement data, the second axis measurement data, and the third axis measurement data. The measurement data in the third format includes the first measurement data for the first axis, the second measurement data for the second axis, and the third measurement data for the third axis. The arrangement of the first axis second measurement data included in the measurement data of the first format, the first axis second measurement data included in the measurement data of the second format, and the first axis first measurement data included in the measurement data of the third format is the same. The arrangement of the second axis measurement data included in the measurement data of the first format, the second axis measurement data included in the measurement data of the second format, and the second axis measurement data included in the measurement data of the third format is the same. The arrangement of the third-axis measurement data included in the measurement data of the first format, the third-axis measurement data included in the measurement data of the second format, and the third-axis measurement data included in the measurement data of the third format may be the same.

[0151] According to this inertial sensor module, measurement data in the first format, second format In both the first-format and third-format measurement data, the arrangement of the measurement data for the first, second, and third axes is the same. Therefore, regardless of whether the output is the first-format, second-format, or third-format measurement data, the external device can perform calculations using the measurement data for the first, second, and third axes in the same way.

[0152] In one embodiment of the inertial sensor module, The processing device may calculate first interpolation data for a predetermined time using the first detection signals at least two times, calculate second interpolation data for the predetermined time using the second detection signals at least two times, and output the measurement data based on the first interpolation data and the second interpolation data based on the output instruction information.

[0153] This inertial sensor module allows for the output of measurement data including synchronized first and second complementary data, even if the detection timing and detection cycle differ between the first and second inertial sensors. Therefore, external devices can perform correct calculations based on the first and second complementary data.

[0154] In one embodiment of the inertial sensor module, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, The aforementioned processing apparatus is The first measurement data of the first axis obtained by correcting the detection signal of the first axis included in the first detection signal, the second measurement data of the second axis obtained by correcting the detection signal of the second axis included in the first detection signal, the third measurement data of the third axis obtained by correcting the detection signal of the third axis included in the first detection signal, and the second measurement data of the first axis obtained by correcting the detection signal of the first axis included in the second detection signal are calculated. When the output format selection information is information for selecting the fourth format, the measurement data in the fourth format is output based on the output instruction information. The measurement data in the fourth format may include the first axis first measurement data, the second axis measurement data, the third axis measurement data, the first axis second measurement data, the first axis first detection data which is the detection signal of the first axis included in the first detection signal, the second axis detection data which is the detection signal of the second axis included in the first detection signal, the third axis detection data which is the detection signal of the third axis included in the first detection signal, and the first axis second detection data which is the detection signal of the first axis included in the second detection signal.

[0155] This inertial sensor module can output measurement data including first axis first detection data, first axis first measurement data corrected from the first axis first detection data, second axis detection data, second axis measurement data corrected from the second axis detection data, third axis detection data, third axis measurement data corrected from the third axis detection data, first axis second detection data, and first axis second measurement data corrected from the first axis second detection data. Therefore, an external device can, for example, compare the first axis first measurement data, second axis measurement data, third axis measurement data, and first axis second measurement data with the first axis first detection data, second axis detection data, third axis detection data, and first axis second detection data, respectively, to determine whether the correction process performed by the processing unit is normal or to evaluate the degree of the correction process.

[0156] In one embodiment of the inertial sensor module, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, The aforementioned processing apparatus is When the output format selection information is information for selecting the fifth format, the detection signal of the first axis included in the second detection signal, the detection signal of the second axis included in the first detection signal Based on the detection signal and the detection signal of the third axis included in the first detection signal, first inertial data including at least one of attitude, velocity, and angle is calculated, and based on the output instruction information, the measurement data in the fifth format including the first inertial data is output. When the output format selection information is information for selecting the sixth format, second inertia data including at least one of attitude, velocity, and angle may be calculated based on the detection signal of the first axis included in the first detection signal, the detection signal of the second axis included in the first detection signal, and the detection signal of the third axis included in the first detection signal, and the measurement data in the sixth format including the second inertia data may be output based on the output instruction information.

[0157] According to this inertial sensor module, an external device can perform calculations based on the first inertial data included in the fifth format measurement data, or on the second inertial data included in the sixth format measurement data.

[0158] One embodiment of an inertial measurement system is: One embodiment of the inertial sensor module, A monitoring device that monitors the measurement data and transmits the output format selection information corresponding to the monitoring result to the processing device, It is equipped with.

[0159] According to this inertial measurement system, the monitoring device can change the format of the measurement data based on the monitoring results of the measurement data output from the inertial sensor module.

[0160] Another aspect of the inertial measurement system is: One embodiment of the inertial sensor module, A monitoring device that monitors the measurement data and transmits the output format selection information corresponding to the monitoring result to the processing device, Equipped with, The aforementioned monitoring device is The first measurement data of the first axis and the second measurement data of the first axis included in the measurement data of the first format output from the processing device are compared, and based on the comparison result, it is determined whether or not the second inertial sensor is malfunctioning, and the output format selection information corresponding to the determination result is output to the processing device. The output format selection information output to the processing unit when the monitoring device determines that the second inertial sensor is not malfunctioning is different from the output format selection information output to the processing unit when the monitoring device determines that the second inertial sensor is malfunctioning.

[0161] According to this inertial measurement system, the monitoring device can change the format of the measurement data output from the inertial sensor module depending on whether or not the second inertial sensor is faulty. Therefore, the external device can perform calculations based on the measurement data output from the inertial sensor module regardless of whether or not the second inertial sensor is faulty. As a result, the external device can concentrate on calculation processing based on the measurement data, thus simplifying its own processing. [Explanation of symbols]

[0162] 1...Inertial measurement system, 2...Inertial sensor module, 3...Host device, 4...Monitoring device, 10...First inertial sensor, 11...First sensor element, 12...Second sensor element, 13...Third sensor element, 14...Fourth sensor element, 15...Fifth sensor element, 16...Sixth sensor element, 17...Processing circuit, 20...Second inertial sensor, 21...Sensor element, 22...Processing circuit, 30...Processing device, 31...Digital interface circuit, 32...Processing circuit, 33 …Host interface circuit, 40…Temperature sensor, 51…Outer case, 52…Notch hole, 53…First recess, 53a…Bottom, 54…Second recess, 54a…Receiving part, 55…Storage part, 60…Joining member, 65…Circuit board, 65a…First surface, 65b…Second surface, 66…Connector, 70…Inner case, 71…Opening, 73…Third recess, 80…Screw, 81…Mounting surface of mounted object, 91…Third inertial sensor, 92…Fourth inertial sensor, 171…Detection circuit, 172…Interface circuit, 221…Detection circuit, 222…Interface circuit, 321…Register section, 322…Detection signal acquisition circuit, 323…Calculation circuit, 324…Measurement data generation circuit

Claims

1. First inertial sensor and, The second inertial sensor, A processing device that receives a first detection signal output from the first inertial sensor and a second detection signal output from the second inertial sensor, and outputs measurement data based on the first detection signal and the second detection signal based on output instruction information input from an external source, Equipped with, The processing device outputs the measurement data in a format corresponding to the output format selection information input from an external source. The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, The aforementioned processing apparatus is The first measurement data of the first axis obtained by correcting the detection signal of the first axis included in the first detection signal, the second measurement data of the second axis obtained by correcting the detection signal of the second axis included in the first detection signal, the third measurement data of the third axis obtained by correcting the detection signal of the third axis included in the first detection signal, and the second measurement data of the first axis obtained by correcting the detection signal of the first axis included in the second detection signal are calculated. When the output format selection information is information for selecting the fourth format, the measurement data in the fourth format is output based on the output instruction information. An inertial sensor module wherein the measurement data in the fourth format includes the first axis first measurement data, the second axis measurement data, the third axis measurement data, the first axis second measurement data, the first axis first detection data which is the detection signal of the first axis included in the first detection signal, the second axis detection data which is the detection signal of the second axis included in the first detection signal, the third axis detection data which is the detection signal of the third axis included in the first detection signal, and the first axis second detection data which is the detection signal of the first axis included in the second detection signal.

2. In claim 1, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, The processing device uses the output format selection information as information for selecting a first format. At some point, based on the output instruction information, the measurement data in the first format is output. An inertial sensor module wherein the measurement data in the first format includes first axis first measurement data based on the detection signal of the first axis included in the first detection signal, second axis measurement data based on the detection signal of the second axis included in the first detection signal, third axis measurement data based on the detection signal of the third axis included in the first detection signal, and first axis second measurement data based on the detection signal of the first axis included in the second detection signal.

3. In claim 1, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, When the output format selection information is information to select a second format, the processing device outputs the measurement data in the second format based on the output instruction information, and when the output format selection information is information to select a third format, it outputs the measurement data in the third format based on the output instruction information. The measurement data in the second format includes first axis second measurement data based on the first axis detection signal included in the second detection signal, second axis measurement data based on the second axis detection signal included in the first detection signal, and third axis measurement data based on the third axis detection signal included in the first detection signal. An inertial sensor module wherein the measurement data in the third format includes first axis first measurement data, second axis measurement data, and third axis measurement data based on the detection signal of the first axis included in the first detection signal.

4. In claim 2, When the output format selection information is information to select a second format, the processing device outputs the measurement data in the second format based on the output instruction information, and when the output format selection information is information to select a third format, it outputs the measurement data in the third format based on the output instruction information. The measurement data in the second format includes the first axis second measurement data, the second axis measurement data, and the third axis measurement data. The measurement data in the third format includes the first measurement data for the first axis, the second measurement data for the second axis, and the third measurement data for the third axis. The arrangement of the first axis second measurement data included in the measurement data of the first format, the first axis second measurement data included in the measurement data of the second format, and the first axis first measurement data included in the measurement data of the third format is the same. The arrangement of the second axis measurement data included in the measurement data of the first format, the second axis measurement data included in the measurement data of the second format, and the second axis measurement data included in the measurement data of the third format is the same. An inertial sensor module in which the arrangement of the third-axis measurement data included in the measurement data of the first format, the third-axis measurement data included in the measurement data of the second format, and the third-axis measurement data included in the measurement data of the third format is the same.

5. In claim 1, The processing device is an inertial sensor module that calculates first interpolation data for a predetermined time using the first detection signals at least two times, calculates second interpolation data for the predetermined time using the second detection signals at least two times, and outputs the measurement data based on the first interpolation data and the second interpolation data based on the output instruction information.

6. In claim 1, The first inertial sensor has the first axis, second axis, and third axis as detection axes, The second inertial sensor uses the first axis as the detection axis, The aforementioned processing apparatus is When the output format selection information is information for selecting a fifth format, first inertial data including at least one of attitude, velocity, and angle is calculated based on the detection signal of the first axis included in the second detection signal, the detection signal of the second axis included in the first detection signal, and the detection signal of the third axis included in the first detection signal, and the measurement data of the fifth format including the first inertial data is output based on the output instruction information. An inertial sensor module that, when the output format selection information is information for selecting a sixth format, calculates second inertial data including at least one of attitude, velocity, and angle based on the detection signal of the first axis included in the first detection signal, the detection signal of the second axis included in the first detection signal, and the detection signal of the third axis included in the first detection signal, and outputs the measurement data in the sixth format including the second inertial data based on the output instruction information.

7. An inertial sensor module according to any one of claims 1 to 6, A monitoring device that monitors the measurement data and transmits the output format selection information corresponding to the monitoring result to the processing device, An inertial measurement system equipped with [the following features].

8. The inertial sensor module according to claim 2, A monitoring device that monitors the measurement data and transmits the output format selection information corresponding to the monitoring result to the processing device, Equipped with, The aforementioned monitoring device is The first measurement data of the first axis and the second measurement data of the first axis included in the measurement data of the first format output from the processing device are compared, and based on the comparison result, it is determined whether or not the second inertial sensor is malfunctioning, and the output format selection information corresponding to the determination result is output to the processing device. An inertial measurement system in which the output format selection information output to the processing device when the monitoring device determines that the second inertial sensor is not malfunctioning is different from the output format selection information output to the processing device when the monitoring device determines that the second inertial sensor is malfunctioning.

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