JP6154883B2 - Stillness determination device, posture angle detection device, portable device, stillness determination method, and program - Google Patents

Description

  The present invention relates to a stillness determination device and a stillness determination method that perform stillness determination using angular velocity data input from an angular velocity sensor, and a posture angle detection device and a portable device using the stillness determination device.

Conventionally, the posture angle detection device determines that the position is stopped when the variance of the angular velocity data detected by the angular velocity sensor is smaller than a preset threshold (for example, Patent Document 1).
[Patent Document 1] Japanese Patent Laid-Open No. 9-96535

  However, there is a problem that the posture angle detection device that is determined using the dispersion of the angular velocity data is erroneously determined to be in a stationary state even though the posture angle detection device is actually operating. Specifically, the attitude angle detection device makes a stationary determination by rotating the angular motion at a constant speed, thereby reducing the dispersion of the angular speed. Thus, in the method described in Patent Document 1, an erroneous determination may occur when performing a still determination. For this reason, the attitude angle detection device must use a steering angle sensor or the like in addition to the angular velocity sensor, and cannot perform stillness determination only with the angular velocity sensor.

  In the first aspect of the present invention, the angular velocity sensor outputs a distribution determination unit that determines whether or not the distribution of angular velocity data output from the angular velocity sensor mounted on the device has a predetermined distribution characteristic. Whether the device is stationary based on the determination unit that compares the value of the angular velocity data with a predetermined first threshold, the distribution characteristics of the angular velocity data, and the comparison result between the value of the angular velocity data and the first threshold There is provided a stillness determination device including a stillness determination unit for determining whether or not.

  In the second aspect of the present invention, the distribution determination unit that compares the characteristic value indicating the distribution characteristic of the angular velocity data output from the angular velocity sensor mounted on the device with the second threshold and outputs the comparison result, and the comparison A stationary determination unit that determines whether the device is stationary based on the result, and the distribution determination unit provides a stationary determination device that controls the second threshold based on the angular velocity data.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

1 is a diagram showing an outline of an attitude angle detection device 10. FIG. 4 is a flowchart illustrating posture calculation of the posture angle detection device 10. It is a figure which shows the angular velocity data which the attitude | position angle detection apparatus 10 acquires. It is a figure which shows the standard deviation which the distribution determination part 120 calculates. It is a figure which shows the peak to peak value of the angular velocity data which the distribution determination part 120 calculates. It is a figure which shows the angular velocity data at the time of stationary and constant velocity circular motion which the stationary determination apparatus 100 acquires. 3 is a flowchart showing a stillness determination method of the stillness determination device 100. It is a figure which shows angular velocity when the stationary determination apparatus 100 is moving with the angular velocity of a fixed period. An example in which the attitude angle detection device 10 is mounted on a portable device 210 is shown. 2 shows an exemplary hardware configuration of a computer 1900 according to an embodiment of the present invention.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a diagram illustrating an outline of a posture angle detection apparatus 10 according to the present embodiment. The posture angle detection device 10 includes a stillness determination device 100, an offset calculation unit 150, a magnetic sensor 160, an acceleration sensor 170, a first posture angle detection unit 180, a second posture angle detection unit 190, and a posture angle calculation unit 200. Prepare.

  The attitude angle detection device 10 calculates the second attitude angle based on the magnetic data detected by the magnetic sensor 160 and the acceleration data detected by the acceleration sensor 170. Further, the posture angle detection device 10 calculates the first posture angle based on the angular velocity data measured by the stillness determination device 100. Here, the second posture angle is a posture angle calculated from magnetic data or acceleration data detected at an arbitrary time. The first posture angle is a posture angle calculated by accumulating the angular velocity data measured by the stillness determination apparatus 100 from an arbitrary time to the current time at a second posture angle at an arbitrary time. It is.

  The stillness determination apparatus 100 includes an angular velocity sensor 110, a distribution determination unit 120, an absolute value determination unit 130, and a stillness determination unit 140. The angular velocity sensor 110 detects angular velocity data of the posture angle detection device 10. The angular velocity sensor 110 is less susceptible to the external environment of the posture angle detection device 10 than the magnetic sensor 160 or the acceleration sensor 170. Therefore, the posture angle detection apparatus 10 can stably calculate the posture angle from the angular velocity data without being affected by the external environment.

  However, the angular velocity data detected by the angular velocity sensor 110 includes errors such as offset and noise due to temperature drift and the like. Further, the attitude angle obtained from the angular velocity data is calculated by accumulating the angular velocity data from an arbitrary time to the current time. Therefore, the error included in the angular velocity data is accumulated in the first posture angle calculated from the subsequent angular velocity data.

  The angular velocity sensor 110 outputs the detected angular velocity data to the distribution determination unit 120 and the absolute value determination unit 130. The distribution determining unit 120 determines whether or not the distribution of angular velocity data detected by the angular velocity sensor 110 has a predetermined distribution characteristic. The distribution characteristic is, for example, a characteristic indicating variation or change amount of angular velocity data. The distribution characteristic may be a characteristic determined by the shape of the distribution of angular velocity data when the horizontal axis is the value of angular velocity data and the vertical axis is the frequency.

  Specifically, the distribution determining unit 120 determines in advance that one of characteristic values selected from the standard deviation indicating the variation in the distribution of the angular velocity data, the variance, and the peak-to-peak value indicating the amount of change between the angular velocity data. It is determined whether or not it is equal to or less than the second threshold value. Further, the distribution determination unit 120 determines whether or not a characteristic value indicating how much the angular velocity data distribution such as the kurtosis of the distribution deviates from the normal distribution is equal to or less than a predetermined second threshold value. May be. The absolute value determination unit 130 compares the value of the angular velocity data detected by the angular velocity sensor 110 with a predetermined first threshold value. Further, the value of the angular velocity data may be an absolute value of the angular velocity data detected by the angular velocity sensor 110.

  The determination result of the distribution determination unit 120 and the comparison result of the absolute value determination unit 130 are input to the stillness determination unit 140. The stationary determination unit 140 determines whether or not the vehicle is stationary based on the distribution characteristics of the angular velocity data and the comparison result between the value of the angular velocity data and the first threshold value. Stillness determination unit 140 may determine that the distribution of angular velocity data has a predetermined distribution characteristic and that the absolute value of angular velocity data is equal to or less than the first threshold value. By using the two indexes of the distribution characteristic and the absolute value, the stillness determination unit 140 can accurately detect the stationary state of the posture angle detection device 10.

  The offset calculation unit 150 receives the determination result determined by the stillness determination unit 140 and the angular velocity data detected by the angular velocity sensor 110. Stillness determination unit 140 may output angular velocity data to offset calculation unit 150 when it is determined to be still. In other words, the offset calculation unit 150 estimates the offset of the angular velocity data using the angular velocity data input when the stillness determination unit 140 determines that it is stationary.

  The posture angle detection device 10 estimates the offset of the angular velocity sensor 110 and removes the offset from the angular velocity data. Here, the offset is defined as angular velocity data output when the angular velocity sensor 110 is in a stationary state. That is, the posture angle detection device 10 can calculate an offset from the angular velocity data when the stillness determination unit 140 determines the stillness.

  The first posture angle detection unit 180 receives the angular velocity data detected by the angular velocity sensor 110 and the offset value estimated by the offset calculation unit 150. The first posture angle detector 180 detects the first posture angle based on the angular velocity data and the offset. Specifically, the first posture angle detection unit 180 removes the offset by subtracting the input offset value from the angular velocity data. The first posture angle detection unit 180 detects the first posture angle by accumulating the angular velocity data from which the offset is removed for a predetermined time. As described above, since the stillness determination unit 140 can accurately determine the stationary state, the first posture angle detection unit 180 can accurately detect the first posture angle based on the offset calculated with high accuracy. .

  The magnetic sensor 160 detects the direction of geomagnetism relative to the attitude angle detection device 10. However, the magnetic sensor 160 cannot accurately detect the geomagnetism in an environment where the magnetic field is unstable or an environment where the magnetism other than the geomagnetism is strong. The acceleration sensor 170 detects the direction of gravitational acceleration with respect to the posture angle detection device 10. However, the acceleration sensor 170 cannot accurately detect the gravitational acceleration when the posture angle detection device 10 has motion acceleration.

  The second attitude angle detection unit 190 receives magnetic data output from the magnetic sensor 160 and acceleration data output from the acceleration sensor 170. In addition, the second posture angle detection unit 190 calculates the second posture angle based on the input magnetic data and acceleration data. Since the second posture angle is detected from the current data without using the past data, no past error is accumulated. However, the second posture angle includes the influence of magnetism other than geomagnetism or motion acceleration. Therefore, the second posture angle detection unit 190 calculates the second posture when a predetermined condition such as magnetism other than geomagnetism and motion acceleration is equal to or less than a predetermined threshold is satisfied.

  The posture angle calculator 200 receives the first posture angle calculated by the first posture angle detector 180 and the second posture angle calculated by the second posture angle detector 190. The posture angle calculation unit 200 basically detects the first posture angle as the posture angle of the posture angle detection device 10. In addition, when the second posture angle detection unit 190 detects the second posture angle, the posture angle calculation unit 200 corrects the first posture angle based on the second posture angle. Specifically, the first posture angle is corrected so that the difference between the second posture angle and the first posture angle is small.

  FIG. 2 is a flowchart showing the posture calculation of the posture angle detection device 10. In step S <b> 201, the angular velocity sensor 110 detects angular velocity data of the posture angle detection device 10. In step S202, the stillness determination unit 140 determines whether or not the posture angle detection device 10 is stationary based on the angular velocity data detected in step S201.

  In step S203, the offset calculation unit 150 estimates the offset of the angular velocity sensor 110 based on the angular velocity data at rest. In step S204, the first posture angle detection unit 180 calculates angular velocity data from which the offset has been removed by subtracting the offset estimated in step S203 from the angular velocity data. In step S205, the first posture angle detection unit 180 calculates the first posture angle of the posture angle detection device 10 from the angular velocity data from which the offset has been removed. The first posture angle detection unit 180 calculates the current first posture angle by rotating the first posture angle calculated one unit time ago according to the current angular velocity data. Thereby, the posture angle detection device 10 can calculate the first posture angle in which the influence of the offset is accurately reduced.

  FIG. 3 is a diagram illustrating angular velocity data acquired by the angular velocity sensor 110, where the vertical axis indicates the angular velocity and the horizontal axis indicates time. The absolute value determination unit 130 sets a first threshold value and compares the first threshold value with the value of angular velocity data input from the angular velocity sensor 110. The absolute value determination unit 130 calculates an absolute value based on the angular velocity data. The absolute value determination unit 130 may compare the first threshold value with the absolute value of the angular velocity data.

  The absolute value determination unit 130 compares each angular velocity data with the first threshold, and sets a period during which the angular velocity data is lower than the first threshold as a period during which the posture angle detection device 10 is stationary. In the present invention, as the angular velocity data to be compared with the first threshold value, in addition to the absolute value of the angular velocity data, an average value, maximum value, minimum value, cumulative value, median value, etc. of the angular velocity data can be used. Further, the absolute value determination unit 130 may detect the maximum absolute value of the angular velocity data within a predetermined period. In this case, the absolute value determination unit 130 sets a period in which the maximum absolute value is lower than the first threshold as a period during which the posture angle detection device 10 is stationary.

  FIG. 4 is a diagram illustrating the standard deviation calculated by the distribution determining unit 120, where the horizontal axis indicates angular velocity and the curve indicates frequency. The average value of each distribution is arranged at the origin of the horizontal axis. Distribution 1 shows a distribution example when the attitude angle detection device 10 is stationary, and the variation is relatively small. Distribution 2 shows a distribution example when the attitude angle detection device 10 is operating, and the variation in angular velocity is larger than the variation in distribution 1.

  When the posture angle detection device 10 is stationary, the angular velocity ideally shows a value of 0 and the standard deviation is 0. However, the distribution in the case where the posture angle detection device 10 is stationary causes a deviation because the angular velocity is dispersed to a value other than 0 due to the influence of noise caused by the external environment. In addition, when the attitude angle detection device 10 is moving, the angular velocity variation range is larger than when the posture angle detection device 10 is stationary. Therefore, the distribution 2 has a larger variation in angular velocity than the distribution 1. That is, the distribution 2 has a standard deviation larger than that of the distribution 1.

  Here, the distribution determination unit 120 calculates the distribution of the angular velocity data input from the angular velocity sensor 110 and calculates the standard deviation. The distribution determination unit 120 compares the standard deviation calculated from the distribution of the angular velocity data with the second threshold value.

  FIG. 5 is a diagram illustrating the peak-to-peak value of the angular velocity data calculated by the distribution determining unit 120. The vertical axis represents angular velocity, and the horizontal axis represents time. The distribution determination unit 120 calculates a peak-to-peak value that is a difference between the maximum value and the minimum value of the angular velocity data within a predetermined period as the characteristic value of the angular velocity data. In addition, the distribution determination unit 120 compares the peak-to-peak value with the second threshold value. When the attitude angle detection device 10 is moving, the variation range of the angular velocity is larger than that when the posture angle detection device 10 is stationary. Therefore, the variation amount of the angular velocity data indicated by the peak-to-peak value or the like is also large. The distribution determination unit 120 determines that the distribution of the angular velocity data has a predetermined distribution characteristic when all of the plurality of characteristic values (for example, standard deviation and peak-to-peak value) are equal to or less than the corresponding threshold values. It's okay.

  FIG. 6 is a diagram showing angular velocity data at the time of stationary and constant velocity circular motion acquired by the stationary determination device 100. The vertical axis represents angular velocity, and the horizontal axis represents time. The stillness determination apparatus 100 performs stillness determination based on the absolute value and the characteristic value of the angular velocity data. In the following, when the stillness determination apparatus 100 determines a stillness based on the absolute value of the angular velocity data and the characteristic value of the angular velocity data, the accuracy of the stillness determination is improved as compared with the case where it is based only on the characteristic value of the angular velocity data. This will be described with reference to FIG.

  As shown on the left side of FIG. 6, when the posture angle detection device 10 is stationary, the value of the angular velocity input to the absolute value determination unit 130 is substantially constant. However, as described above, since the angular velocity data output from the angular velocity sensor 110 includes an offset, the value of the angular velocity input to the absolute value determination unit 130 does not become a zero value. As shown on the right side of FIG. 6, when the attitude angle detection device 10 is moving at a constant angular velocity such as a constant velocity circular motion, the angular velocity is substantially constant.

  In the case of determining stillness based only on the characteristic value of the angular velocity data, when the posture angle detection device 10 moves at a constant angular velocity such as a uniform circular motion and exhibits a characteristic value smaller than the second threshold, The determination apparatus 100 erroneously determines that it is stationary.

  On the other hand, when the stillness determination device 100 determines the stillness based on the absolute value and the characteristic value of the angular velocity data, the posture angle detection device 10 is moving at a constant angular velocity such as a constant velocity circular motion. When the absolute value of the angular velocity data is larger than the first threshold value, the stationary determination device 100 can determine that it is in an operating state. Hereinafter, a specific flow of the stillness determination method based on the absolute value and the characteristic value of the angular velocity data will be described.

  FIG. 7 is a flowchart showing a stillness determination method of the stillness determination device 100 according to this embodiment. In step S701, the angular velocity sensor 110 detects angular velocity data. In step S <b> 702, the stillness determination apparatus 100 buffers the detected angular velocity data and outputs the buffered angular velocity data to the distribution determination unit 120.

  Next, in step S703, the distribution determination unit 120 calculates, from the angular velocity data detected by the angular velocity sensor 110, the standard deviation of the angular velocity data distribution or the peak-to-peak value of the angular velocity data as the characteristic value of the angular velocity data. In step S704, the distribution determination unit 120 compares the distribution of the angular velocity data with a predetermined distribution characteristic. Specifically, the characteristic value distribution of the angular velocity data detected in step S703 is compared with the second threshold value.

  In step S704, if the characteristic value of the angular velocity data is less than or equal to the second threshold value, step S705 is executed. If the characteristic value of the angular velocity data is not less than or equal to the second threshold value, the posture angle detection device 10 is operating. It is determined (S708).

  In steps S705 and S706, the absolute value determination unit 130 calculates the absolute value of the angular velocity data from the angular velocity data detected by the angular velocity sensor 110, and compares the absolute value of the angular velocity data with a predetermined first threshold value. In step S706, when the characteristic value of the angular velocity data is equal to or smaller than the first threshold value, step S707 is executed. When the characteristic value of the angular velocity data is not equal to or smaller than the first threshold value, the posture angle detection device 10 is operating. It is determined (S708).

  In step S707, the stillness determination unit 140 determines that the posture angle detection device 10 is stationary. That is, when the characteristic value of the angular velocity data is equal to or smaller than the second threshold value (S704) and the absolute value of the angular velocity data is equal to or smaller than the first threshold value (S706), the stillness determination unit 140 determines the state of the posture angle detection device 10 Is determined to be stationary. On the other hand, when at least one of the characteristic value and the absolute value of the angular velocity data is equal to or less than the corresponding threshold value, the stillness determination unit 140 determines that the posture angle detection device 10 is operating (S708).

  By such processing, the stationary state and the operating state of the attitude angle detection device 10 can be accurately determined. For example, even when the posture angle detection device 10 is moving at a constant speed, if the absolute value of the angular velocity is larger than the first threshold value, the posture angle detection device 10 can be determined as the operating state. Although the absolute value of the angular velocity of the posture angle detection device 10 is small, even when the posture angle detection device 10 is operating in a predetermined pattern, the posture angle detection device 10 can be determined as an operating state from the distribution of angular velocity. This reduces the possibility of erroneously detecting the operating state as a stationary state, and reduces the possibility of detecting an offset based on the output of the angular velocity sensor 110 in the operating state. For this reason, the offset of the angular velocity sensor 110 can be detected with high accuracy.

  So far, the method of calculating the attitude angle based on the angular velocity data without using the magnetic sensor 160 and the acceleration sensor 170 has been described. In the present embodiment, the posture angle detection device 10 calculates the posture angle based on angular velocity data that is less influenced by the external environment, and thus is highly reliable against changes in the external environment.

  However, the posture angle detection device 10 may correct the first posture angle based on the angular velocity data based on the magnetic data and the acceleration data indicating the second posture angle. In this case, the posture angle calculation unit 200 receives the first posture angle calculated by the first posture angle detection unit 180 and the second posture angle calculated by the second posture angle detection unit 190.

  In general, the first posture angle based on the angular velocity data has a detection cycle shorter than that of the second posture angle based on the magnetic data and the acceleration data, and is not easily influenced by the external environment. On the other hand, the second posture angle based on the magnetic data and the acceleration data has a longer detection cycle than the first posture angle, but there is no accumulation of noise or errors.

  Therefore, the posture angle calculation unit 200 basically detects the first posture angle as the posture angle of the posture angle detection device 10 for the purpose of avoiding the influence of the external environment. Further, the posture angle calculation unit 200 corrects the first posture angle based on the second posture angle. As a result, the posture angle calculation unit 200 periodically corrects the posture angle using the second posture angle even when the posture angle error based on the angular velocity data is accumulated, so that the posture angle deviates greatly from the true value. Can be prevented.

  FIG. 8 is a diagram illustrating an angular velocity when the stationary determination device 100 is moving at an angular velocity that changes at a constant period. The angular velocity data shown in FIG. 8 shows a case where the stationary determination device 100 is moving with the absolute value of the angular velocity data being always smaller than the first threshold value. When the stillness determination device 100 determines the stillness based only on the absolute value of the angular velocity data, the angular velocity data is always a value smaller than the first threshold value, so that it is erroneously determined as still.

  On the other hand, the standard deviation of the dispersion in the operation state shown in FIG. 8 is larger than the standard deviation of the dispersion in the stationary state. Therefore, since the stillness determination apparatus 100 can determine from the distribution of the angular velocity data that the posture angle detection apparatus 10 is operating, it can prevent erroneous determination of the stillness.

  Further, as shown in FIG. 8, when the fluctuation of the angular velocity includes a component other than the random component, the distribution of the angular velocity data deviates from the normal distribution. For example, in the case shown in FIG. 8, the distribution of the angular velocity data is a sine wave distribution. Normally, the angular velocity data output by the angular velocity sensor 110 when stationary includes a lot of random noise components. For this reason, it can be determined from the shape of the distribution of the angular velocity data that the attitude angle detection device 10 is operating.

  The distribution determination unit 120 may control the second threshold value according to the absolute value of the angular velocity data. For example, when the absolute value of the angular velocity data is larger, the second threshold value may be made smaller. For example, even when the absolute value of the angular velocity data is smaller than the first threshold value, the greater the absolute value, the higher the possibility that the posture angle detection device 10 is actually operating. For this reason, in order to prevent the operation state from being erroneously detected as the still state, the second threshold value is reduced and the criterion for determining the still state is tightened. Moreover, the absolute value determination unit 130 may control the first threshold value according to the characteristic value of the angular velocity data. For example, when the characteristic value of the angular velocity data is larger, the first threshold value may be made smaller.

  FIG. 9 shows an example in which the attitude angle detection device 10 according to the present embodiment is mounted on a portable device 210. A direction from the lower part to the upper part of the portable device 210 is defined as an x-axis, a direction from the right side to the left side of the portable device 210 is defined as a y-axis, and a direction from the rear surface of the portable device 210 toward the entire surface is defined as a z-axis. Here, the angle around the x axis is defined as the roll angle, the angle around the y axis as the pitch angle, and the angle around the z axis as the yaw angle. That is, the three axes of the x-axis, the y-axis, and the z-axis are orthogonal to each other.

  The posture angle detection device 10 detects angular velocity, magnetism, and acceleration at the roll angle, pitch angle, and yaw angle, respectively. Based on these, the attitude angle detection device 10 measures the attitude of the mobile device 210.

  The attitude angle detection device 10 may be mounted on a portable device 210, a car navigation system, an automatic driving system, a robot, and the like. The mobile device 210 may include a mobile phone, a digital camera, a wristwatch, and the like.

  FIG. 10 shows an example of a hardware configuration of a computer 1900 according to the present embodiment. A computer 1900 according to this embodiment is connected to a CPU peripheral unit having a CPU 2000, a RAM 2020, a graphic controller 2075, and a display device 2080 that are connected to each other by a host controller 2082, and to the host controller 2082 by an input / output controller 2084. Input / output unit having communication interface 2030, hard disk drive 2040, and CD-ROM drive 2060, and legacy input / output unit having ROM 2010, flexible disk drive 2050, and input / output chip 2070 connected to input / output controller 2084 With.

  The host controller 2082 connects the RAM 2020 to the CPU 2000 and the graphic controller 2075 that access the RAM 2020 at a high transfer rate. The CPU 2000 operates based on programs stored in the ROM 2010 and the RAM 2020 and controls each unit. The graphic controller 2075 acquires image data generated by the CPU 2000 or the like on a frame buffer provided in the RAM 2020 and displays it on the display device 2080. Instead of this, the graphic controller 2075 may include a frame buffer for storing image data generated by the CPU 2000 or the like.

  The input / output controller 2084 connects the host controller 2082 to the communication interface 2030, the hard disk drive 2040, and the CD-ROM drive 2060, which are relatively high-speed input / output devices. The communication interface 2030 communicates with other devices via a network. The hard disk drive 2040 stores programs and data used by the CPU 2000 in the computer 1900. The CD-ROM drive 2060 reads a program or data from the CD-ROM 2095 and provides it to the hard disk drive 2040 via the RAM 2020.

  The input / output controller 2084 is connected to the ROM 2010, the flexible disk drive 2050, and the relatively low-speed input / output device of the input / output chip 2070. The ROM 2010 stores a boot program that the computer 1900 executes at startup and / or a program that depends on the hardware of the computer 1900. The flexible disk drive 2050 reads a program or data from the flexible disk 2090 and provides it to the hard disk drive 2040 via the RAM 2020. The input / output chip 2070 connects the flexible disk drive 2050 to the input / output controller 2084 and inputs / outputs various input / output devices via, for example, a parallel port, a serial port, a keyboard port, a mouse port, and the like. Connect to controller 2084.

  A program provided to the hard disk drive 2040 via the RAM 2020 is stored in a recording medium such as the flexible disk 2090, the CD-ROM 2095, or an IC card and provided by the user. The program is read from the recording medium, installed in the hard disk drive 2040 in the computer 1900 via the RAM 2020, and executed by the CPU 2000.

  A program that is installed in the computer 1900 and causes the computer 1900 to function as a stillness determination apparatus includes a distribution determination module, a determination module, and a stillness determination module. These programs or modules work on the CPU 2000 or the like to cause the computer 1900 to function as a stillness determination device.

  Information processing described in these programs is read by the computer 1900, and as a distribution determination unit, determination unit, and stillness determination unit, which are specific means in which software and the various hardware resources described above cooperate. Function. And by these specific means, the calculation or processing of information according to the purpose of use of the computer 1900 in the present embodiment is realized, so that a unique stillness determination device according to the purpose of use is constructed.

  As an example, when communication is performed between the computer 1900 and an external device or the like, the CPU 2000 executes a communication program loaded on the RAM 2020 and executes a communication interface based on the processing content described in the communication program. A communication process is instructed to 2030. Under the control of the CPU 2000, the communication interface 2030 reads transmission data stored in a transmission buffer area or the like provided on a storage device such as the RAM 2020, the hard disk drive 2040, the flexible disk 2090, or the CD-ROM 2095, and sends it to the network. The reception data transmitted or received from the network is written into a reception buffer area or the like provided on the storage device. As described above, the communication interface 2030 may transfer transmission / reception data to / from the storage device by a DMA (direct memory access) method. Instead, the CPU 2000 transfers the storage device or the communication interface 2030 as a transfer source. The transmission / reception data may be transferred by reading the data from the data and writing the data to the communication interface 2030 or the storage device of the transfer destination.

  The CPU 2000 is all or necessary from among files or databases stored in an external storage device such as a hard disk drive 2040, a CD-ROM drive 2060 (CD-ROM 2095), and a flexible disk drive 2050 (flexible disk 2090). This portion is read into the RAM 2020 by DMA transfer or the like, and various processes are performed on the data on the RAM 2020. Then, CPU 2000 writes the processed data back to the external storage device by DMA transfer or the like. In such processing, since the RAM 2020 can be regarded as temporarily holding the contents of the external storage device, in the present embodiment, the RAM 2020 and the external storage device are collectively referred to as a memory, a storage unit, or a storage device. Various types of information such as various programs, data, tables, and databases in the present embodiment are stored on such a storage device and are subjected to information processing. Note that the CPU 2000 can also store a part of the RAM 2020 in the cache memory and perform reading and writing on the cache memory. Even in such a form, the cache memory bears a part of the function of the RAM 2020. Therefore, in the present embodiment, the cache memory is also included in the RAM 2020, the memory, and / or the storage device unless otherwise indicated. To do.

  In addition, the CPU 2000 performs various operations, such as various operations, information processing, condition determination, information search / replacement, etc., described in the present embodiment, specified for the data read from the RAM 2020 by the instruction sequence of the program. Is written back to the RAM 2020. For example, when performing the condition determination, the CPU 2000 determines whether the various variables shown in the present embodiment satisfy the conditions such as large, small, above, below, equal, etc., compared to other variables or constants. When the condition is satisfied (or not satisfied), the program branches to a different instruction sequence or calls a subroutine.

  Further, the CPU 2000 can search for information stored in a file or database in the storage device. For example, in the case where a plurality of entries in which the attribute value of the second attribute is associated with the attribute value of the first attribute are stored in the storage device, the CPU 2000 displays the plurality of entries stored in the storage device. The entry that matches the condition in which the attribute value of the first attribute is specified is retrieved, and the attribute value of the second attribute that is stored in the entry is read, thereby associating with the first attribute that satisfies the predetermined condition The attribute value of the specified second attribute can be obtained.

The program or module shown above may be stored in an external recording medium. As the recording medium, in addition to the flexible disk 2090 and the CD-ROM 2095, an optical recording medium such as DVD or CD, a magneto-optical recording medium such as MO, a tape medium, a semiconductor memory such as an IC card, and the like can be used. Further, a storage device such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet may be used as a recording medium, and the program may be provided to the computer 1900 via the network.
[Effect of the invention]

  In the present invention, it is possible to determine stillness of an object that is moving at a constant speed by using only the angular velocity sensor by using the two determination criteria of the absolute value and the distribution of the angular velocity in combination.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The execution order of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior”. It should be noted that they can be implemented in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for the sake of convenience, it means that it is essential to carry out in this order. is not.

DESCRIPTION OF SYMBOLS 10 ... Attitude angle detection apparatus, 100 ... Stillness determination apparatus, 110 ... Angular velocity sensor, 120 ... Distribution determination part, 130 ... Absolute value determination part, 140 ... Stillness determination part, 150 ... Offset calculation unit, 160 ... Magnetic sensor, 170 ... Acceleration sensor, 180 ... First posture angle detection unit, 190 ... Second posture angle detection unit, 200 ... Posture Angle calculation unit, 210 ... portable device, 1900 ... computer, 2000 ... CPU, 2010 ... ROM, 2020 ... RAM, 2030 ... communication interface, 2040 ... hard disk drive, 2050 ... Flexible disk drive, 2060 ... CD-ROM drive, 2070 ... Input / output chip, 2075 ... Graphic controller, 2 80 ... display unit, 2082 ... host controller, 2084 ... output controller, 2090 ... flexible disk, 2095 ... CD-ROM

Claims (11)

A distribution determination unit that determines whether or not a characteristic value indicating a distribution characteristic of angular velocity data output from an angular velocity sensor mounted on the device is equal to or less than a predetermined second threshold ;
An absolute value determination unit that compares the value of the angular velocity data output by the angular velocity sensor with a predetermined first threshold;
A stationary determination unit that determines that the characteristic value of the angular velocity data is equal to or less than the second threshold value and that is stationary when the absolute value of the angular velocity data is equal to or less than the first threshold value ,
The absolute value determination unit, the characteristic value of the angular velocity data that controls smaller the first threshold is greater than static determination device.   The stationary determination unit determines that the angular velocity data is stationary when the distribution of the angular velocity data has the predetermined distribution characteristic and the absolute value of the angular velocity data is equal to or less than the first threshold value. The stationary determination apparatus according to claim 1, wherein the stationary determination apparatus is characterized. Characteristic value indicating the distribution characteristic of the angular velocity data, the still determining device according to claim 1 or 2 which is either characteristic value indicating the characteristic value and the change amount indicating a variation of the distribution of the angular velocity data. The stationary determination device according to any one of claims 1 to 3 , wherein the distribution determination unit controls the second threshold value based on the angular velocity data. The stationary determination apparatus according to claim 4 , wherein the distribution determination unit controls the second threshold value according to an absolute value of the angular velocity data. A distribution determination unit that compares a characteristic value indicating a distribution characteristic of angular velocity data output from an angular velocity sensor mounted on the device with a second threshold value, and outputs the comparison result;
A stationary determination unit that determines whether or not the device is stationary based on the comparison result,
The distribution determination unit controls the second threshold value to be smaller when the absolute value of the angular velocity data is larger . The stationary determination device according to any one of claims 1 to 6 , which detects a stationary state of the device,
An offset calculation unit that calculates an offset in the output of the angular velocity sensor based on the output of the angular velocity sensor when the stationary determination device detects a stationary state;
An attitude angle detection device comprising: an angular velocity data detected by the angular velocity sensor; and an attitude angle detection unit that detects an attitude angle of the device based on the offset calculated by the offset calculation unit. A portable device comprising the stationary determination device according to any one of claims 1 to 6 . A distribution determination step for determining whether or not a characteristic value indicating a distribution characteristic of angular velocity data output from an angular velocity sensor mounted on the device is equal to or less than a predetermined second threshold ;
An absolute value determination step of comparing the value of the angular velocity data output by the angular velocity sensor with a predetermined first threshold;
A stationary determination step of determining whether or not the device is stationary based on the distribution characteristics of the angular velocity data and a comparison result between the value of the angular velocity data and the first threshold ,
The absolute value determination stage, stationary judgment method the characteristic value of the angular velocity data that controls smaller the first threshold value is greater than. A distribution determination step of comparing a characteristic value indicating a distribution characteristic of angular velocity data output from an angular velocity sensor mounted on the device with a second threshold, and outputting the comparison result;
A stationary determination step of determining whether or not the device is stationary based on the comparison result,
In the distribution determination step, the second threshold value is controlled to be smaller when the absolute value of the angular velocity data is larger . A program that causes a computer to function as the stillness determination device according to any one of claims 1 to 6 .

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