Inertia sensor module

Abstract

To provide a method to accelerate a sensor module using a simple arithmetic processing device.SOLUTION: An inertia sensor module comprises: an inertia sensor unit; and N (N is an integer equal to or greater than 2) arithmetic processing devices. The N arithmetic processing devices performs start of sampling and output of a processing result in a predetermined order.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an inertial sensor module. [Background technology]

[0002] Conventionally, a configuration in which an output from an inertial sensor device is processed by a processing unit is known. For example, Patent Document 1 discloses a configuration in which an X-axis angular velocity sensor device, a Y-axis angular velocity sensor device, a Z-axis angular velocity sensor device, and an acceleration sensor device are connected to a microcontroller (processing unit). The microcontroller performs processing based on the outputs from these sensor devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-163955 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional technology, signals from multiple sensor devices are processed by a single microcontroller. This requires the microcontroller to have high performance to process signals from multiple sensor devices, which is an obstacle to creating a sensor module that operates at high speed. For this reason, there has been a demand for a technology that uses a simpler configuration and can achieve higher speeds than a configuration in which signals from multiple sensor devices are processed by a single microcontroller. [Means for solving the problem]

[0005] An inertial sensor module as one embodiment for solving the above problem comprises an inertial sensor unit and N (N is an integer greater than or equal to 2) arithmetic processing devices that sample the output of the inertial sensor unit, process the results of the sampling, and output the results of the processing, and the N arithmetic processing devices start the sampling and output the results of the processing in a predetermined order. [Brief explanation of the drawings]

[0006] [Figure 1] 1 shows a configuration example of an inertial sensor module according to a first embodiment. [Figure 2] 4 is a timing chart of the operation of each part of the inertial sensor module according to the first embodiment. [Figure 3] 10 is a configuration example of an inertial sensor module according to a second embodiment. [Figure 4] 10 is a timing chart of the operation of each part of the inertial sensor module according to the second embodiment. [Figure 5] 10 shows a configuration example of an inertial sensor module according to a third embodiment. [Figure 6] 10 is a timing chart of the operation of each part of the inertial sensor module according to the third embodiment. [Figure 7] 10 is a configuration example of an inertial sensor module according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] A preferred embodiment of the present invention will be described in detail below. Note that the present embodiment described below does not limit the content of the present invention as defined in the claims, and not all of the configurations described in the present embodiment are necessarily essential as means for solving the problems of the present invention.

[0008] (1) First embodiment 1 shows an example of the configuration of an inertial sensor module 10 according to this embodiment. In this embodiment, the inertial sensor module 10 is communicably connected to a host 30. The inertial sensor module 10 and the host 30 communicate with each other according to a predetermined communication standard (for example, the SPI standard).

[0009] The inertial sensor module 10 is a module including a plurality of sensor elements that detect values ​​related to inertia. In this embodiment, the inertial sensor module 10 includes an inertial sensor unit 11, a first arithmetic processing device 21, and a second arithmetic processing device 22.

[0010] In this embodiment, the inertial sensor unit 11 includes a three-axis angular velocity sensor device 11a and a three-axis acceleration sensor device 11b. The three-axis angular velocity sensor device 11a is a sensor that detects angular velocity. The three-axis angular velocity sensor device 11a includes sensor elements that detect angular velocity in the rotation direction around three predetermined mutually orthogonal axes. The three-axis angular velocity sensor device 11a detects, for example, angular velocity around the X-axis, Y-axis, and Z-axis. The three-axis angular velocity sensor device 11a also includes an analog circuit, an A / D conversion circuit, and an interface (not shown). When the three-axis angular velocity sensor device 11a detects angular velocity, the analog circuit performs predetermined processing on the detection result, and the processed analog signal indicating the angular velocity is converted into digital data by the A / D conversion circuit. The digital data output from the A / D conversion circuit is output to the first arithmetic processing device 21 and the second arithmetic processing device 22 via the interface.

[0011] The three-axis acceleration sensor device 11b is a sensor that detects acceleration. The three-axis acceleration sensor device 11b includes a sensor element that detects acceleration in each of three predetermined mutually orthogonal axes. The three-axis acceleration sensor device 11b detects, for example, acceleration in the X-axis direction, acceleration in the Y-axis direction, and acceleration in the Z-axis direction. The three-axis acceleration sensor device 11b also includes an analog circuit, an A / D conversion circuit, and an interface. That is, an analog signal indicating acceleration detected by the sensor element is processed by the analog circuit, converted into digital data by the A / D conversion circuit, and output to the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0012] The predetermined processing executed by the analog circuits in the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b may be various processes. The analog circuits may include, for example, an amplifier circuit that amplifies signals from the sensor elements, a detection circuit such as a synchronous detection circuit, a gain adjustment circuit, or an offset adjustment circuit. The A / D conversion circuit may employ various A / D conversion methods, such as successive approximation, delta-sigma, flash, pipeline, or double integration. The interfaces that output digital data from each sensor to the first and second arithmetic processing units 21 and 22 may employ interfaces that transmit and receive serial data. Specifically, these interfaces may perform interface processing based on communication standards such as SPI and I2C. Alternatively, they may perform interface processing based on communication standards that are an extension of SPI or I2C, or communication standards that are partially improved or modified from SPI or I2C. In this embodiment, digital data indicating the angular velocity and acceleration of each of the three axes is output serially. In addition, in communication standards such as SPI and I2C, there may be multiple wires used for communication, but in the diagram, multiple wires are not explicitly shown and are schematically shown by a single line (same below).

[0013] In this embodiment, the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b are connected to the first arithmetic processing device 21 and the second arithmetic processing device 22 by electrically conducting signal lines. Therefore, the digital data output from the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b can be acquired by both the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0014] The first arithmetic processing unit 21 includes a first interface 21a, a processing unit 21b, a RAM 21c, a second interface 21d, and a third interface 21e. In this embodiment, the first arithmetic processing unit 21 is an integrated circuit device and can be realized by a processor such as an MPU or CPU. Alternatively, the first arithmetic processing unit 21 may be realized by an ASIC using automatic placement and routing such as a gate array.

[0015] In this embodiment, the processing unit 21b is a function realized by executing a predetermined program, while the first interface 21a, RAM 21c, second interface 21d, and third interface 21e are realized by hardware.

[0016] The RAM 21c is a memory capable of storing any information. In this embodiment, setting information and information used for correction processing are stored in the RAM 21c. The setting information is information for specifying the mode and various operations of the first arithmetic processing unit 21. The information used for correction processing is information for correcting the temperature characteristics of the sensor element, etc.

[0017] The first interface 21a, the second interface 21d, and the third interface 21e are interfaces for performing data communication between the first arithmetic processing device 21 and other devices. For example, the first interface 21a is an interface for the first arithmetic processing device 21 to acquire digital data output from the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b.

[0018] The second interface 21d is an interface through which the first arithmetic processing unit 21 acquires commands output from the host 30 and transmits digital data output by the first arithmetic processing unit 21 to the host 30. The third interface 21e is an interface through which a synchronization signal SYNC for operating in synchronization with the second arithmetic processing unit 22 is exchanged between the first arithmetic processing unit 21 and the second arithmetic processing unit 22.

[0019] The processing unit 21b performs predetermined processing based on the output of the inertial sensor unit 11. Specifically, the processing unit 21b samples the output of the inertial sensor unit 11, performs processing based on the sampling results, and outputs the processing results. The sampling is a process of sequentially acquiring output values ​​serially output from the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b. In this embodiment, the first arithmetic processing unit 21 performs sampling at a predetermined sampling period. That is, the processing unit 21b starts sampling the output of the inertial sensor unit 11 at a predetermined timing and sequentially acquires the three-axis angular velocities and three-axis accelerations output from the inertial sensor unit 11 via the first interface 21a. Then, when the predetermined sampling period has elapsed after the start of sampling, the processing unit 21b starts sampling again.

[0020] After sampling, the processing unit 21b performs various processes based on the acquired triaxial angular velocities and triaxial accelerations, such as correcting output errors caused by the temperature characteristics of the inertial sensors of the triaxial angular velocity sensor device 11a and the triaxial acceleration sensor device 11b.

[0021] After various processes have been performed, the processing unit 21b outputs the processed values, i.e., the three-axis angular velocity and three-axis acceleration values, to the host 30 via the second interface 21d. Note that the processing unit 21b can perform various processes in addition to the above processes. For example, the processing unit 21b can execute processes in response to commands from the host 30, processes for synchronizing the first arithmetic processing unit 21 and the second arithmetic processing unit 22, and the like.

[0022] The second arithmetic processing device 22 has a configuration similar to that of the first arithmetic processing device 21 and can execute similar functions. However, the processing unit 21b of the first arithmetic processing device 21 is capable of executing a process of generating a synchronization signal SYNC and outputting it to the second arithmetic processing device 22 via the third interface 21e. The first arithmetic processing device 21 and the second arithmetic processing device 22 can start processing based on the synchronization signal SYNC. That is, in this embodiment, the two arithmetic processing devices, the first arithmetic processing device 21 and the second arithmetic processing device 22, determine the timing to start sampling in accordance with a common synchronization signal. This configuration makes it possible to synchronize the first arithmetic processing device 21 and the second arithmetic processing device 22 with a simple configuration.

[0023] In this embodiment, the first interface 21a included in the first arithmetic processing device 21 is electrically connected to the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b of the inertial sensor unit 11. Furthermore, the first interface 22a included in the second arithmetic processing device 22 is connected to the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b of the inertial sensor unit 11. The signal lines connected to these first interfaces 21a and the signal lines connected to the first interface 22a are electrically connected. Therefore, both the first arithmetic processing device 21 and the second arithmetic processing device 22 can acquire digital data output from the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b.

[0024] In this embodiment, the second interface 21d and the second interface 22d are interfaces for communicating with the host 30, and are electrically connected to the terminal T by an electrically conductive signal line. The host 30 is electrically connected to the inertial sensor module 10 via the terminal T. Therefore, the host 30 acquires both the signals output from the second interface 21d and the second interface 22d as signals output from the inertial sensor module 10.

[0025] The second interface 21d and the second interface 22d may be interfaces that transmit and receive serial data, for example. Specifically, these interfaces perform interface processing for communication standards such as SPI and I2C. Alternatively, they may perform interface processing for a communication standard that is an extension of SPI or I2C, or a communication standard that is an improvement or modification of the SPI or I2C standard.

[0026] In this embodiment, the inertial sensor module 10 operates in various modes. When the inertial sensor module 10 is powered on, initialization and other processes are performed, and then the inertial sensor module 10 operates in the configuration mode. In the configuration mode, the inertial sensor module 10 can accept a setting information instruction command. When a sampling start command is accepted in the configuration mode or a predetermined transition condition is met, the inertial sensor module 10 transitions to the sampling mode.

[0027] In the sampling mode, the three-axis angular velocity and three-axis acceleration detected by the inertial sensor unit 11 are transmitted from the inertial sensor module 10 to the host 30. Various transmission modes are possible, but here, a burst mode in which data is continuously transferred will be described. The burst mode is a mode in which data is continuously transferred in response to a command to execute continuous transfer being transmitted from the host 30.

[0028] When the burst mode is started, the first arithmetic processing device 21 and the second arithmetic processing device 22 sample and correct the output results of the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b, and output the results to the host 30. In this embodiment, the first arithmetic processing device 21 and the second arithmetic processing device 22 start sampling at a predetermined cycle of 1000 μs (i.e., at a cycle of 1 kHz).

[0029] To perform sampling at a predetermined cycle, it is necessary to perform sampling, processing based on the sampling results, and output the processing results within the predetermined cycle, and therefore the first arithmetic processing unit 21 and the second arithmetic processing unit 22 must have the performance to perform these processes within the predetermined cycle.

[0030] One way to speed up detection is to speed up the cycle in which the inertial sensor unit 11 outputs. The cycle in which the inertial sensor unit 11 outputs is the length of time from the output start timing to the next output start timing in the operation in which the inertial sensor unit 11 starts output, stops output, and starts output again. However, if an attempt is made to process the output of the inertial sensor unit 11 with a faster cycle using a single arithmetic processing device, the sampling cycle of the arithmetic processing device needs to be equal to or greater than the output cycle of the inertial sensor unit 11. Therefore, in order to speed up detection, the arithmetic processing device also needs to be faster, which makes the configuration of the arithmetic processing device complex.

[0031] Therefore, in this embodiment, the inertial sensor module 10 is equipped with two arithmetic processing devices with longer operating cycles than the inertial sensor unit 11, thereby making the output cycle from the inertial sensor module 10 match the output cycle of the inertial sensor unit 11. Specifically, in this embodiment, the default cycle at which the first arithmetic processing device 21 and the second arithmetic processing device 22 perform sampling is 1000 μs, and the output cycle of the inertial sensor unit 11 is 500 μs.

[0032] That is, when the number of arithmetic processing devices is N (=2), the period of 500 μs at which the inertial sensor unit 11 outputs is 1 / N of the period of 1000 μs at which one arithmetic processing device samples. Also, the period of 500 μs at which the inertial sensor unit 11 outputs is 1 / N of the period of 1000 μs at which one arithmetic processing device samples.

[0033] As described above, in this embodiment, the sampling period of the first arithmetic processing device 21 and the second arithmetic processing device 22 is longer than the output period of the inertial sensor unit 11. However, in this embodiment, by shifting the timing at which the sampling of the first arithmetic processing device 21 and the second arithmetic processing device 22 starts, the output period to the host 30 is configured not to be longer than the output period of the inertial sensor unit 11.

[0034] Specifically, the two arithmetic processing devices, the first arithmetic processing device 21 and the second arithmetic processing device 22, are configured to start sampling and output processing results in a predetermined order. In this embodiment, the first arithmetic processing device 21 and the second arithmetic processing device 22 perform processing alternately, so that the first arithmetic processing device 21 processes digital data that starts to be output from the inertial sensor unit 11 in a certain cycle, and the other, the second arithmetic processing device 22, processes digital data that starts to be output in the next cycle. Furthermore, the first arithmetic processing device 21 processes digital data that starts to be output in the next cycle. Thereafter, the second arithmetic processing device 22 and the first arithmetic processing device 21 perform processing in turn.

[0035] Furthermore, if one of the two arithmetic processing devices (first arithmetic processing device 21 and second arithmetic processing device 22) is a processing device that starts sampling in the first order and the other is a processing device that starts sampling in the second order, the difference in timing between the processing device that starts sampling in the first order and the processing device that starts sampling in the second order, and the difference in timing between the processing device that starts sampling in the first order and the processing device that starts sampling in the second order, are shorter than the sampling period of one arithmetic processing device. Specifically, in this embodiment, the difference in timing between the first arithmetic processing device 21 and the second arithmetic processing device 22 start sampling is 500 μs, which is 1 / N of the sampling period of 1000 μs of the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0036] FIG. 2 is a timing chart of the operation of each part of the inertial sensor module 10 according to this embodiment. Six types of timing are shown in chronological order in FIG. 2. The first and second timing charts from the top are timing charts showing the data communication operations of the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b, respectively. The third and fifth timing charts from the top are timing charts showing the operations of the first arithmetic processing device 21 and the second arithmetic processing device 22, respectively. The fourth timing chart from the top is a timing chart of the synchronization signal SYNC output from the first arithmetic processing device 21 to the second arithmetic processing device 22. The sixth timing chart is a timing chart of the signal output from the inertial sensor module 10 to the host 30.

[0037] In response to instructions from the first arithmetic processing device 21 and the second arithmetic processing device 22, the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b output detection values ​​at a cycle of Ts (500 μs). For example, in FIG. 2, the three-axis angular velocity sensor device 11a starts outputting digital data indicating angular velocity at time t1 and completes output at time t2. Then, at time t7, which is the cycle Ts after time t1, it starts outputting digital data again.

[0038] 2, the triaxial acceleration sensor device 11b starts outputting digital data indicating acceleration at time t2, completes output of the digital data at time t3, and starts outputting the digital data again at time t8, which is the period Ts after time t2.

[0039] When the triaxial angular velocity sensor device 11a outputs digital data indicating angular velocity during the period from timing t1 to t2, the first arithmetic processing device 21 acquires the digital data during the period from timing t1 to t2. Similarly, when the triaxial acceleration sensor device 11b outputs digital data indicating acceleration during the period from timing t2 to t3, the first arithmetic processing device 21 acquires the digital data during the period from timing t2 to t3. On the other hand, the second arithmetic processing device 22 does not acquire digital data during the period from timing t1 to t3.

[0040] When the first arithmetic processing unit 21 acquires digital data at times t1 to t3, the processing unit 21b of the first arithmetic processing unit 21 performs processing such as correction based on the acquired digital data. In the example shown in Fig. 2, the first arithmetic processing unit 21 performs this processing at times t4 to t5. When this processing is completed, the processing unit 21b outputs the processed digital data to the host 30 via the second interface 21d. In the example shown in Fig. 2, the output of digital data to the host 30 is shown as the sixth from the top, and is performed at times t5 to t6.

[0041] The first arithmetic processing unit 21 operates in a cycle Tm that is twice as long as the cycle Ts of the digital data output from the inertial sensor unit 11. That is, the first arithmetic processing unit 21 starts acquiring digital data again at timing t13, which is the cycle Tm after timing t1 when the first arithmetic processing unit 21 starts acquiring digital data.

[0042] The first arithmetic processing unit 21 also generates the synchronization signal SYNC. In this embodiment, when the first arithmetic processing unit 21 starts acquiring digital data output from the triaxial angular velocity sensor device 11a, it changes the signal level of the synchronization signal SYNC from low to high. It also starts counting time at timing t1, and after timing t1, when the period Ts during which the triaxial angular velocity sensor device 11a outputs digital data has elapsed, it changes the signal level of the synchronization signal SYNC to low. In the example shown in FIG. 2, the synchronization signal SYNC changes from high to low at timing t7.

[0043] When the synchronization signal SYNC changes from high level to low level, the second arithmetic processing unit 22 starts acquiring digital data. Specifically, when the triaxial angular velocity sensor device 11a outputs digital data indicating angular velocity during the period from timing t7 to t8, the second arithmetic processing unit 22 acquires the digital data during the period from timing t7 to t8. Similarly, when the triaxial acceleration sensor device 11b outputs digital data indicating acceleration during the period from timing t8 to t9, the second arithmetic processing unit 22 acquires the digital data during the period from timing t8 to t9. On the other hand, the first arithmetic processing unit 21 does not acquire digital data during the period from timing t7 to t9.

[0044] When the second arithmetic processing device 22 acquires digital data at times t7 to t9, the processing unit 22b of the second arithmetic processing device 22 performs processing such as correction based on the acquired digital data. In the example shown in Fig. 2, the second arithmetic processing device 22 performs this processing at times t10 to t11. When this processing is completed, the processing unit 22b outputs the processed digital data to the host 30 via the second interface 22d. In the example shown in Fig. 2, the output of digital data to the host 30 is shown as the sixth from the top, and is performed at times t11 to t12.

[0045] The second arithmetic processing device 22 also operates in a cycle Tm that is twice as long as the cycle Ts of the digital data output from the inertial sensor unit 11. Therefore, the second arithmetic processing device 22 starts acquiring digital data again at a timing (not shown) after the cycle Tm has elapsed from the timing t7 at which the second arithmetic processing device 22 started acquiring digital data.

[0046] As described above, the first arithmetic processing device 21 and the second arithmetic processing device 22 operate at a cycle twice the output cycle of the digital data from the three-axis angular velocity sensor device 11a and the three-axis acceleration sensor device 11b. The first arithmetic processing device 21 and the second arithmetic processing device 22 operate at the same cycle, but the timings at which they start acquiring digital data are shifted from each other by half the time length (=cycle Ts) of the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0047] 2, the output cycle of digital data to the host 30 is a cycle Ts that is half the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22. Therefore, although the operation cycle of each of the first arithmetic processing device 21 and the second arithmetic processing device 22 is longer than the operation cycle of the inertial sensor unit 11, the operation cycle of the entire inertial sensor module 10 as seen from the host 30 is equal to the operation cycle of the inertial sensor unit 11.

[0048] In the above configuration, the two arithmetic processing units alternately start sampling and output the processing results. Therefore, it is not necessary to process the digital data output from the inertial sensor unit 11 in a single processing unit, and the configuration of the arithmetic processing unit can be simplified.

[0049] Furthermore, the difference in timing between when the first arithmetic processing device 21, which starts sampling in the first order, and the second arithmetic processing device 22, which starts sampling in the second order, starts sampling, and the difference in timing between when they output the processing results, are shorter than the sampling cycle of one arithmetic processing device. Therefore, digital data can be output from the inertial sensor module 10 in a cycle shorter than the operating cycle of the arithmetic processing device.

[0050] Furthermore, the cycle Ts at which the inertial sensor unit 11 outputs is half the cycle Tm at which one arithmetic processing device samples. With this configuration, it is possible to configure an inertial sensor module 10 that operates at a cycle equivalent to the operation cycle of the inertial sensor unit 11, using a arithmetic processing device with an operation cycle longer than the output cycle of the inertial sensor unit 11. Therefore, it is possible to configure a sensor module that operates at high speed with a simple configuration.

[0051] (2) Second embodiment In the first embodiment described above, the sampling period of the first arithmetic processing device 21 and the second arithmetic processing device 22 is longer than the period in which the inertial sensor unit 11 outputs, but the former period may be equal to the latter period. In this case, the period in which the inertial sensor module 10 outputs can be shorter than the period in which the inertial sensor unit 11 outputs.

[0052] Fig. 3 is a block diagram showing an inertial sensor module 100 according to such an example. Note that in Fig. 3, the same components as those in Fig. 1 are denoted by the same reference numerals. That is, the inertial sensor module 100 differs from the configuration shown in Fig. 1 in the configuration of the inertial sensor unit 110. The inertial sensor unit 110 included in the inertial sensor module 100 includes three-axis angular velocity sensor devices 110a and 110c and three-axis acceleration sensor devices 110b and 110d.

[0053] The three-axis angular velocity sensor devices 110a and 110c have the same configuration as the three-axis angular velocity sensor device 11a, and the three-axis acceleration sensor devices 110b and 110d have the same configuration as the three-axis acceleration sensor device 11b. The three-axis angular velocity sensor devices 110a and 110c are two inertial sensor devices that measure the same measurement object. That is, each of the three-axis angular velocity sensor devices 110a and 110c includes a sensor element that detects angular velocity in a rotation direction about each of the same three orthogonal axes. The three-axis angular velocity sensor devices 110a and 110c detect, for example, angular velocity around the X-axis, the Y-axis, and the Z-axis. The three-axis acceleration sensor devices 110b and 110d are two inertial sensor devices that measure the same measurement object. That is, each of the three-axis acceleration sensor devices 110b and 110d includes a sensor element that detects acceleration in a direction along each of the same three orthogonal axes. The three-axis acceleration sensor devices 110b and 110d detect, for example, acceleration in the X-axis direction, acceleration in the Y-axis direction, and acceleration in the Z-axis direction.

[0054] In the inertial sensor module 100, each of the two arithmetic processing devices (the first arithmetic processing device 21 and the second arithmetic processing device 22) is connected to a different one of the two inertial sensor devices that measure the same measurement target. Specifically, the three-axis angular velocity sensor device 110a is connected to the first interface 21a of the first arithmetic processing device 21, but is not connected to the first interface 22a of the second arithmetic processing device 22. In addition, the three-axis angular velocity sensor device 110c is connected to the first interface 22a of the second arithmetic processing device 22, but is not connected to the first interface 21a of the first arithmetic processing device 21.

[0055] Furthermore, the three-axis acceleration sensor device 110b is connected to the first interface 21a of the first arithmetic processing device 21, but is not connected to the first interface 22a of the second arithmetic processing device 22. Furthermore, the three-axis acceleration sensor device 110d is connected to the first interface 22a of the second arithmetic processing device 22, but is not connected to the first interface 21a of the first arithmetic processing device 21. The three-axis angular velocity sensor device 110a and the three-axis acceleration sensor device 110b are connected to the first interface 21a using a common signal line. The three-axis angular velocity sensor device 110c and the three-axis acceleration sensor device 110d are connected to the first interface 22a using a common signal line.

[0056] In the inertial sensor module 100, the cycle in which the inertial sensor unit 110 performs output is the same as the cycle in which each of one arithmetic processing device, i.e., the first arithmetic processing device 21 and the second arithmetic processing device 22, performs sampling. The difference in timing at which each of the arithmetic processing device that starts sampling in the first order (e.g., the first arithmetic processing device 21) and the arithmetic processing device that starts sampling in the second order (e.g., the second arithmetic processing device 22) starts sampling is 1 / 2 the cycle in which each of the arithmetic processing devices performs sampling.

[0057] FIG. 4 is a timing chart of the operation of each part of the inertial sensor module 100. Eight types of timing are shown in chronological order in FIG. 4. The first, second, fifth, and sixth timing charts from the top show the data communication operations of the three-axis angular velocity sensor device 110a, the three-axis acceleration sensor device 110b, the three-axis angular velocity sensor device 110c, and the three-axis acceleration sensor device 110d, respectively. The third and seventh timing charts from the top show the operations of the first arithmetic processing device 21 and the second arithmetic processing device 22, respectively. The fourth timing chart from the top is a timing chart of the synchronization signal SYNC output from the first arithmetic processing device 21 to the second arithmetic processing device 22. The eighth timing chart from the top is a timing chart of the signal output from the inertial sensor module 100 to the host 30.

[0058] The three-axis angular velocity sensor devices 110a and 110c and the three-axis acceleration sensor devices 110b and 110d output detection values ​​at a period Ts (e.g., 500 μs). For example, in FIG. 4, the three-axis angular velocity sensor device 110a starts outputting digital data indicating angular velocity at time t1 and completes output at time t2. Then, at time t11, which is the period Ts after time t1, it starts outputting digital data again.

[0059] 4, the triaxial acceleration sensor device 110b starts outputting digital data indicating acceleration at time t2, completes output of the digital data at time t3, and starts outputting the digital data again at time t13, which is the period Ts after time t2.

[0060] When the triaxial angular velocity sensor device 110a outputs digital data indicating angular velocity during the period from timing t1 to t2, the first arithmetic processing unit 21 acquires the digital data during the period from timing t1 to t2. Similarly, when the triaxial acceleration sensor device 110b outputs digital data indicating acceleration during the period from timing t2 to t3, the first arithmetic processing unit 21 acquires the digital data during the period from timing t2 to t3.

[0061] When the first arithmetic processing unit 21 acquires digital data at times t1 to t3, the processing unit 21b of the first arithmetic processing unit 21 performs processing such as correction based on the acquired digital data. In the example shown in Fig. 4, the first arithmetic processing unit 21 performs this processing at times t4 to t6. When this processing is completed, the processing unit 21b outputs the processed digital data to the host 30 via the second interface 21d. In the example shown in Fig. 4, the output of digital data to the host 30 is shown as the sixth from the top, and is performed at times t6 to t10.

[0062] In this embodiment, the first arithmetic processing device 21 operates in a cycle Tm having the same length as the cycle Ts of the digital data output from the inertial sensor unit 11. That is, the first arithmetic processing device 21 starts acquiring digital data again at timing t11, which is the cycle Tm after timing t1 when the first arithmetic processing device 21 starts acquiring digital data.

[0063] The first arithmetic processing unit 21 also generates the synchronization signal SYNC. In this embodiment, when the first arithmetic processing unit 21 starts acquiring digital data output from the triaxial angular velocity sensor device 110a, it changes the signal level of the synchronization signal SYNC from low to high. It also starts counting time at timing t1, and after timing t1, when half the period Ts at which the triaxial angular velocity sensor device 110a outputs digital data has elapsed, it changes the signal level of the synchronization signal SYNC to low. In the example shown in FIG. 4, the synchronization signal SYNC changes from high to low at timing t5.

[0064] When the synchronization signal SYNC changes from high to low, the second arithmetic processing unit 22 starts acquiring digital data. Specifically, when the triaxial angular velocity sensor device 110c outputs digital data indicating angular velocity during the period from timing t5 to t7, the second arithmetic processing unit 22 acquires the digital data during the period from timing t5 to t7. Similarly, when the triaxial acceleration sensor device 110d outputs digital data indicating acceleration during the period from timing t7 to t8, the second arithmetic processing unit 22 acquires the digital data during the period from timing t7 to t8.

[0065] When the second arithmetic processing device 22 acquires digital data at times t5 to t8, the processing unit 22b of the second arithmetic processing device 22 performs processing such as correction based on the acquired digital data. In the example shown in Fig. 4, the second arithmetic processing device 22 performs this processing at times t9 to t12. When this processing is completed, the processing unit 22b outputs the processed digital data to the host 30 via the second interface 22d. In the example shown in Fig. 4, the output of digital data to the host 30 is shown as the sixth from the top, and is performed at times t12 to t16.

[0066] The second arithmetic processing device 22 also operates in a cycle Tm having the same length as the cycle Ts of the digital data output from the inertial sensor unit 11. Therefore, the second arithmetic processing device 22 starts acquiring digital data again at timing t17, which is the cycle Tm after timing t5 when the second arithmetic processing device 22 started acquiring digital data.

[0067] As described above, the first arithmetic processing device 21 and the second arithmetic processing device 22 operate in the same cycle as the output cycle of digital data from the triaxial angular velocity sensor device 110a, the triaxial acceleration sensor device 110b, the triaxial angular velocity sensor device 110c, and the triaxial acceleration sensor device 110d. The first arithmetic processing device 21 and the second arithmetic processing device 22 operate in the same cycle, but the timings at which they start acquiring digital data are shifted from each other by Tm / 2 (=Ts / 2), which is half the time length of the operation cycle Tm of the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0068] 4, the output cycle of digital data to the host 30 is Tm / 2 (=Ts / 2), which is half the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22. Therefore, although the operation cycle of each of the first arithmetic processing device 21 and the second arithmetic processing device 22 is the same as the operation cycle of the inertial sensor unit 110, the operation cycle of the entire inertial sensor module 100 as seen from the host 30 is shorter than the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22. In other words, it is possible to speed up the operation.

[0069] In the above configuration, the two arithmetic processing units alternately start sampling and output the processing results. Therefore, it is not necessary to process the digital data output from the inertial sensor unit 110 with a single processing unit, and the configuration of the arithmetic processing unit can be simplified.

[0070] Furthermore, the difference in timing between when the first arithmetic processing device 21, which starts sampling in the first order, and the second arithmetic processing device 22, which starts sampling in the second order, starts sampling, and the difference in timing between when they output the processing results, are shorter than the sampling cycle of one arithmetic processing device. Therefore, digital data can be output from the inertial sensor module 100 in a cycle shorter than the operating cycle of the arithmetic processing device.

[0071] Furthermore, the cycle Ts at which the inertial sensor unit 110 outputs is the same as the cycle Tm at which one arithmetic processing device samples, but the difference in timing at which each arithmetic processing device starts sampling is 1 / 2 the cycle Tm at which one arithmetic processing device samples. With this configuration, it is possible to configure an inertial sensor module 100 that outputs faster than the operating cycle of a arithmetic processing device, using a arithmetic processing device with an operating cycle equivalent to that of the inertial sensor unit 110. Therefore, it is possible to configure a sensor module that operates at high speed with a simple configuration.

[0072] (3) Third embodiment Furthermore, a configuration may be adopted in which detection results of the same measurement object are input to a single arithmetic processing device. In this case, high accuracy can be achieved by statistically processing the measurement results of the same measurement object in the arithmetic processing device. Figure 5 is a block diagram showing an inertial sensor module 101 according to such an example. Note that in Figure 5, the same components as in Figure 1 are designated by the same reference numerals.

[0073] That is, the inertial sensor module 101 has a different configuration of the inertial sensor unit 111 from the configuration shown in Fig. 1. The inertial sensor unit 111 included in the inertial sensor module 101 includes three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d.

[0074] The three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d have the same configuration as the three-axis angular velocity sensor device 11a. The three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d are four inertial sensor devices that measure the same measurement object. That is, each of the three three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d includes a sensor element that detects angular velocity in the rotation direction about each of the same three orthogonal axes.

[0075] In this embodiment, the three-axis angular velocity sensor devices 111a and 111b are connected to a first interface 21a of the first arithmetic processing device 21. Furthermore, the three-axis angular velocity sensor devices 111c and 111d are connected to a first interface 22a of the second arithmetic processing device 22. Here, a plurality of sensor devices connected to the same arithmetic processing device are referred to as an inertial sensor device group. In the example shown in FIG. 5, the three-axis angular velocity sensor devices 111a and 111b form one inertial sensor device group 1111, and the three-axis angular velocity sensor devices 111c and 111d form one inertial sensor device group 1112.

[0076] As described above, the inertial sensor unit 111 according to this embodiment has two inertial sensor device groups 1111 and 1112 each including a plurality of inertial sensor devices that measure the same target of measurement, i.e., three-axis acceleration. Each of the two arithmetic processing devices (the first arithmetic processing device 21 and the second arithmetic processing device 22) is connected to a different one of the two inertial sensor device groups.

[0077] The three-axis angular velocity sensor devices 111a and 111b belonging to the inertial sensor device group 1111 are not connected to the second arithmetic processing device 22, and the three-axis angular velocity sensor devices 111c and 111d belonging to the inertial sensor device group 1112 are not connected to the first arithmetic processing device 21. The three-axis angular velocity sensor devices 111a and 111b are connected to the first interface 21a using a common signal line. The three-axis angular velocity sensor devices 111c and 111d are connected to the first interface 22a using a common signal line.

[0078] In the inertial sensor module 101, the cycle Ts at which the inertial sensor unit 111 performs output is the same as the cycle Tm at which one arithmetic processing device, i.e., the first arithmetic processing device 21 and the second arithmetic processing device 22, performs sampling. The difference in timing at which the arithmetic processing device that starts sampling first in order (e.g., the first arithmetic processing device 21) and the arithmetic processing device that starts sampling second in order (e.g., the second arithmetic processing device 22) start sampling is 1 / 2 (=Ts / 2) of the cycle Tm at which one arithmetic processing device performs sampling.

[0079] FIG. 6 is a timing chart of the operation of each part of the inertial sensor module 101. Eight types of timing are shown in chronological order in FIG. 6. The first, second, fifth, and sixth timing charts from the top are timing charts showing the operation of the three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d, respectively. The third and seventh timing charts from the top are timing charts showing the operation of the first arithmetic processing device 21 and the second arithmetic processing device 22, respectively. The fourth timing chart from the top is a timing chart of the synchronization signal SYNC output from the first arithmetic processing device 21 to the second arithmetic processing device 22. The eighth timing chart from the top is a timing chart of the signal output from the inertial sensor module 101 to the host 30.

[0080] The three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d output detection values ​​in a cycle Ts (e.g., 500 μs). For example, in FIG. 6, the three-axis angular velocity sensor device 111a starts outputting digital data indicating angular velocity at timing t1, and completes output at timing t2. Then, it starts outputting digital data again at timing t13, which is the cycle Ts after timing t1. In the example shown in FIG. 6, the three-axis angular velocity sensor device 111b starts outputting digital data indicating angular velocity at timing t2, the three-axis angular velocity sensor device 111c starts outputting digital data at timing t7, and the three-axis angular velocity sensor device 111d starts outputting digital data indicating angular velocity at timing t8. Furthermore, they start outputting digital data again at a timing the cycle Ts after these timings.

[0081] When the triaxial angular velocity sensor device 111a outputs digital data indicating an angular velocity during the period from timing t1 to t2, the first arithmetic processing unit 21 acquires the digital data during the period from timing t1 to t2. Similarly, when the triaxial angular velocity sensor device 111b outputs digital data indicating an angular velocity during the period from timing t2 to t3, the first arithmetic processing unit 21 acquires the digital data during the period from timing t2 to t3.

[0082] When the first arithmetic processing device 21 acquires digital data at times t1 to t3, the processing unit 21b of the first arithmetic processing device 21 performs processing such as correction based on the acquired digital data. Furthermore, at this time, the processing unit 21b of the first arithmetic processing device 21 performs processing to compile statistics of the sampling results of the three-axis angular velocity sensor devices 111a and 111b. That is, the first arithmetic processing device 21 compiles statistics of the sampling results of the same measurement target of the inertial sensor device group 1111 connected to the first arithmetic processing device 21. The statistics may be implemented in various ways, for example, by processing to calculate an average value, median value, etc. for each axis based on the detected values ​​of the angular velocities of the three axes. By performing such statistics, the angular velocity values ​​for each of the three axes can be acquired with high accuracy.

[0083] 6, the first arithmetic processing unit 21 performs the process from timing t4 to t5. When the process is completed, the processing unit 21b outputs the processed digital data to the host 30 via the second interface 21d. In the example shown in Fig. 6, the output of the digital data to the host 30 is shown as the sixth from the top, and is performed from timing t5 to t6.

[0084] In this embodiment, the first arithmetic processing device 21 operates in a cycle Tm that is the same length as the cycle Ts of the digital data output from the inertial sensor unit 11. That is, the first arithmetic processing device 21 starts acquiring digital data again at timing t13, which is the cycle Tm after timing t1 when the first arithmetic processing device 21 starts acquiring digital data.

[0085] The first arithmetic processing unit 21 also generates a synchronization signal SYNC. In this embodiment, when the first arithmetic processing unit 21 starts acquiring digital data output from the triaxial angular velocity sensor device 111a, it changes the signal level of the synchronization signal SYNC from low to high. It also starts counting time at timing t1, and after timing t1, when ½ (=Tm / 2) of the period Ts at which the triaxial angular velocity sensor device 111a outputs digital data has elapsed, it changes the signal level of the synchronization signal SYNC to low. In the example shown in FIG. 6, the synchronization signal SYNC changes from high to low at timing t7.

[0086] When the synchronization signal SYNC changes from high to low, the second arithmetic processing unit 22 starts acquiring digital data. Specifically, when the triaxial angular velocity sensor device 111c outputs digital data indicating angular velocity during the period from timing t7 to t8, the second arithmetic processing unit 22 acquires the digital data during the period from timing t7 to t8. Similarly, when the triaxial angular velocity sensor device 111d outputs digital data indicating angular velocity during the period from timing t8 to t9, the second arithmetic processing unit 22 acquires the digital data during the period from timing t8 to t9.

[0087] When the second arithmetic processing device 22 acquires digital data between timings t7 and t9, the processing unit 22b of the second arithmetic processing device 22 performs processing such as correction based on the acquired digital data. Furthermore, at this time, the processing unit 22b of the second arithmetic processing device 22 performs processing to compile statistics of the sampling results of the three-axis angular velocity sensor devices 111c and 111d. That is, the second arithmetic processing device 22 compiles statistics of the sampling results of the same measurement target of the inertial sensor device group 1112 connected to the second arithmetic processing device 22. The statistics may be implemented in various ways, for example, by processing to calculate the average value, median value, etc. for each axis based on the detected values ​​of the angular velocities of the three axes. By performing such statistics, the angular velocity values ​​for each of the three axes can be acquired with high accuracy.

[0088] 6, the second arithmetic processing unit 22 performs the process at timings t10 to t11. When the process is completed, the processing unit 22b outputs the processed digital data to the host 30 via the second interface 22d. In the example shown in Fig. 6, the output of the digital data to the host 30 is shown as the sixth from the top, and is performed at timings t11 to t12.

[0089] The second arithmetic processing device 22 also operates in a cycle Tm having the same length as the cycle Ts of the digital data output from the inertial sensor unit 11. Therefore, the second arithmetic processing device 22 starts acquiring digital data again at a timing (not shown) after the cycle Tm has elapsed from the timing t7 at which the second arithmetic processing device 22 starts acquiring digital data again.

[0090] As described above, the first arithmetic processing device 21 and the second arithmetic processing device 22 operate in the same cycle as the output cycle of the digital data from the three-axis angular velocity sensor devices 111a, 111b, 111c, and 111d. The first arithmetic processing device 21 and the second arithmetic processing device 22 operate in the same cycle, but the timings at which they start acquiring digital data are shifted from each other by half the time length (=cycle Ts / 2) of the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22.

[0091] 6, the output cycle of digital data to the host 30 is Ts / 2, which is half the operation cycle of the first arithmetic processing device 21 and the second arithmetic processing device 22. Therefore, the operation cycle of each of the first arithmetic processing device 21 and the second arithmetic processing device 22 is the same as the operation cycle of the inertial sensor unit 111, but the operation cycle of the entire inertial sensor module 101 as seen from the host 30 is shorter than the operation cycle of the inertial sensor unit 111. In this embodiment, statistical values ​​of the detection results of the same measurement target are output from the inertial sensor module 101, so that the accuracy of the output value can be improved.

[0092] In the above configuration, the two arithmetic processing units alternately start sampling and output the processing results. Therefore, it is not necessary to process the digital data output from the inertial sensor unit 111 with a single processing unit, and the configuration of the arithmetic processing unit can be simplified.

[0093] Furthermore, the difference in timing between when the first arithmetic processing device 21, which starts sampling in the first order, and the second arithmetic processing device 22, which starts sampling in the second order, starts sampling, and the difference in timing between when they output the processing results, are shorter than the sampling cycle of one arithmetic processing device. Therefore, digital data can be output from the inertial sensor module 101 in a cycle shorter than the operating cycle of the arithmetic processing device.

[0094] Furthermore, the cycle Ts at which the inertial sensor unit 111 outputs is the same as the cycle Tm at which one arithmetic processing device performs sampling. The difference in timing at which each arithmetic processing device starts sampling is 1 / 2 the cycle Tm at which one arithmetic processing device performs sampling. With this configuration, it is possible to configure an inertial sensor module 101 that operates at a cycle shorter than the operating cycle of the inertial sensor unit 111, using a arithmetic processing device with the same operating cycle as the inertial sensor unit 111.

[0095] (4) Fourth embodiment Furthermore, the number of arithmetic processing devices may be N (N is an integer equal to or greater than 2) and is not limited to two. Fig. 7 is a block diagram showing the configuration of an inertial sensor module 102 equipped with four arithmetic processing devices (first arithmetic processing device 21 to fourth arithmetic processing device 24). In the inertial sensor module 102, a triaxial acceleration sensor device and a triaxial acceleration sensor device are connected to each of the four first arithmetic processing devices 21 to fourth arithmetic processing device 24. Therefore, the inertial sensor module 102 shown in Fig. 7 has a configuration in which the number of arithmetic processing devices and sensor devices is doubled compared to the inertial sensor module 100 shown in Fig. 3.

[0096] In this configuration, by making the output period of each sensor device the same as the sampling period of each arithmetic processing device, it is possible to configure the inertial sensor module 102 to operate at a period that is the same as or shorter than the output period of the sensor device. For example, assume that the output period Ts of each sensor device is the same as the sampling period Tm of each arithmetic processing device, and that the first arithmetic processing devices 21 to 24 start sampling first to fourth, respectively. In this configuration, the difference in timing between the start of sampling by a processing device that starts sampling in the mth order (m is an integer between 1 and 3) and that of a processing device that starts sampling in the (m+1)th order is set to Tm / 4. With this configuration, it is possible to configure the inertial sensor module 102 to output digital data at a period Ts / 4, which is ¼ of the period Ts.

[0097] Furthermore, the output period Ts of each sensor device is the same as the sampling period Tm of each arithmetic processing device, and the first arithmetic processing devices 21 to 23 start sampling first, second, third, respectively. In this configuration, the difference in timing between the arithmetic processing device that starts sampling in the mth order (m is an integer between 1 and 2) and the arithmetic processing device that starts sampling in the (m+1)th order is Tm / 3. With this configuration, it is possible to configure the inertial sensor module 102 to output digital data at a period Ts / 3, which is 1 / 3 of the period Ts. Note that the fourth arithmetic processing device 24 may not be used, and statistical processing may be performed based on the detection results input to the fourth arithmetic processing device 24.

[0098] Similarly, by selecting two arithmetic processing devices from the four first to fourth arithmetic processing devices 21 to 24 and setting the difference in timing at which each arithmetic processing device starts sampling to Tm / 2, an inertial sensor module 102 can be configured that outputs digital data at a period Ts / 2, which is half the period Ts.

[0099] Furthermore, even in the configuration shown in Fig. 1, the number of arithmetic processing units is not limited to two. By increasing the number of arithmetic processing units and sensor devices shown in Fig. 2 by an integer multiple, it is possible to configure an inertial sensor module that operates faster or outputs data with higher accuracy.

[0100] (5) Other embodiments The above-described embodiments are examples for implementing the present invention, and various other embodiments are possible. For example, the configuration of the inertial sensor module is not limited to the above-described configuration, and various modifications are possible, such as omitting some of the components or adding other components. Specifically, in the configurations shown in Figures 1, 3, 5, and 7, each sensor device may be replaced with a 6DOF sensor device. Furthermore, in the configuration of Figure 5, a 3-axis acceleration sensor device may be provided in parallel with each of the 3-axis angular velocity sensor devices. Furthermore, the measurement target of the inertial sensor device is not limited to 3-axis, and may be 2-axis, 1-axis, etc.

[0101] The inertial sensor unit may be any unit capable of outputting a value for evaluating inertia, and may include one or more inertial sensor devices. The inertial sensor device is a device that includes an inertial sensor and is capable of outputting a value detected by the inertial sensor. The inertial sensor may be any sensor that detects a value for evaluating inertia, and may be, for example, an acceleration sensor, an angular acceleration sensor, a velocity sensor, or the like.

[0102] The arithmetic processing device is a device that performs various arithmetic processing based on the output from the inertial sensor unit. Specifically, the arithmetic processing device is required to be able to at least sample the output from the inertial sensor unit, process the sampled results, and output the processed results. Of course, the arithmetic processing device may also be able to perform other processing, such as generating various signals and processing in response to commands from the host.

[0103] Sampling includes a process of converting an analog signal output from the inertial sensor unit into a digital signal, and is performed at a fixed sampling period. If the inertial sensor unit includes multiple inertial sensor devices, when sampling starts, the outputs from the multiple inertial sensor devices are captured sequentially in a predetermined order.

[0104] The processing based on the sampling results may be various processes. For example, in addition to correcting output errors due to the temperature characteristics of the inertial sensor, correction of output errors due to the alignment of the inertial sensor may be included. The processing results may be output to another device that uses the output via a predetermined interface. The output may also be performed at a sampling period.

[0105] Furthermore, the inertial sensor module is equipped with multiple arithmetic processing devices. That is, the output of the inertial sensor unit is sequentially processed by two or more arithmetic processing devices. With this configuration, the performance required for processing at the same cycle is lower than that required for processing the output of the inertial sensor unit with a single arithmetic processing device. For example, the sampling cycle of the arithmetic processing device may be the same as or longer than the output cycle from the inertial sensor unit.

[0106] The order in which the N arithmetic processing devices start sampling and output processing results may be determined in advance. That is, when one arithmetic processing device performs processing based on the output from the inertial sensor unit, another arithmetic processing device performs processing based on the output from the next inertial sensor unit. With this configuration, the sampling period required for each arithmetic processing device can be longer than when the same arithmetic processing device performs processing consecutively, and high processing speeds are not required. [Explanation of symbols]

[0107] 10...inertial sensor module, 11...inertial sensor unit, 11a...three-axis angular velocity sensor device, 11b...three-axis acceleration sensor device, 21...first arithmetic processing device, 21a...first interface, 21b...processing unit, 21c...RAM, 21d...second interface, 21e...third interface, 22...second arithmetic processing device, 22a...first interface, 22b...processing unit, 22d...second interface

Claims

1. an inertial sensor unit; N (N is an integer of 2 or more) arithmetic processing devices that sample the output of the inertial sensor unit, process the sampled output, and output the processed output; The N calculation processing devices start the sampling and output the processing results in a predetermined order. Inertial sensor module.

2. the difference in timing between the arithmetic processing device that starts the sampling in the mth order (m is any integer from 1 to N-1) and the arithmetic processing device that starts the sampling in the (m+1)th order, when the arithmetic processing device starts the sampling, and when the arithmetic processing device outputs the processing results, is shorter than the period in which the sampling is performed in one of the arithmetic processing devices; The inertial sensor module of claim 1 .

3. The cycle in which the inertial sensor unit outputs is 1 / N of the cycle in which one of the arithmetic processing devices performs the sampling. The inertial sensor module according to claim 1 or 2.

4. the N calculation processing devices determine timings to start the sampling based on a common synchronization signal; The inertial sensor module according to claim 1 or 2.

5. Each of the N processing devices has an interface connected to the inertial sensor unit. The inertial sensor module according to claim 1 or 2.

6. the inertial sensor unit has N inertial sensor devices (N is an integer of 2 or more) that measure the same measurement target, each of the N processing units is connected to a different inertial sensor device among the N inertial sensor devices; The inertial sensor module of claim 1 .

7. a cycle in which the inertial sensor unit outputs is the same as a cycle in which one of the arithmetic processing devices performs the sampling; the difference between the timing at which the arithmetic processing device that starts the sampling in the mth order (m is any integer from 1 to N-1) and the timing at which the arithmetic processing device that starts the sampling in the (m+1)th order starts the sampling is 1 / N of the period in which one of the arithmetic processing devices performs the sampling; The inertial sensor module according to claim 6 .

8. the inertial sensor unit has N inertial sensor device groups (N is an integer of 2 or more) each including a plurality of inertial sensor devices that measure the same measurement target; each of the N arithmetic processing devices is connected to a different inertial sensor device group among the N inertial sensor device groups; Each of the N arithmetic processing devices performs statistical processing of sampling results of the same measurement target of the connected inertial sensor device group among the N inertial sensor device group, and outputs the processing results. The inertial sensor module of claim 1 .

Images