JP3851406B2 - Pedestrian speed / direction detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pedestrian movement speed / direction detection device suitable for application to a walking route guidance device that can be carried by a pedestrian, for example.
[0002]
[Prior art]
As a technology related to the pedestrian movement speed / direction detection device, for example, an automobile navigation system can be listed. In this system, the position of the own vehicle is obtained by satellite navigation using GPS, and the position, traveling direction, etc. of the own vehicle are displayed on a map on the display.
[0003]
In addition, even if a car navigation system cannot receive radio waves from GPS satellites, it can detect the position of the vehicle by so-called inertial navigation by using a distance sensor and rate sensor. It is also known to make it possible.
[0004]
On the other hand, as a navigation system that can be carried by a pedestrian, for example, there is a technique disclosed in JP-A-8-202982. In this technique, a GPS receiver is used as means for detecting the current position of the pedestrian, and a gyroscope or a geomagnetic sensor is used as means for detecting the walking direction.
[0005]
[Problems to be solved by the invention]
However, when considering using the conventional automobile navigation system as a pedestrian movement speed / direction detection device, it is impossible to detect the position of a pedestrian when walking in a building or building. Thus, even if the navigation system has inertial navigation, there is a problem of how to detect the moving distance or moving speed when walking in a building or building.
[0006]
On the other hand, when using the above-described navigation system that can be carried by a pedestrian as a pedestrian movement speed / direction detection device, the pedestrian always holds the portable navigation system in a fixed orientation. There is no guarantee that the output is upside down and left and right. In addition, since this navigation system that can be carried by a pedestrian uses a GPS receiver, a geomagnetic sensor, and the like, there is a problem that it is difficult to detect the position of the pedestrian with sufficient accuracy.
[0007]
The present invention has been made in consideration of such a problem, and it is possible to detect the moving speed and direction for a pedestrian that can detect the moving speed and direction even if the pedestrian is carrying it in any state. An object is to provide a detection device.
[0008]
Another object of the present invention is to provide a pedestrian movement speed / direction detection device capable of accurately detecting the movement speed / direction.
[0009]
[Means for Solving the Problems]
The present invention comprises a three-axis acceleration detection means,
3-axis rate detection means;
A gravitational acceleration direction detecting means for detecting a gravitational acceleration direction from an output of the triaxial acceleration detecting means;
Gravity direction tracking means for calculating a correction value from the output of the triaxial rate detection means, with the gravitational acceleration direction obtained by the gravitational acceleration direction detection means as an initial gravitational acceleration direction;
Acceleration signal correcting means for correcting the output of the triaxial acceleration detecting means based on the correction value;
Rate signal correction means for correcting the signal of the triaxial rate detection means based on the correction value;
Detecting a vertical vibration component with respect to the ground surface from the output of the acceleration signal correcting means, and detecting a walking cycle of a pedestrian as a walking cycle;
A moving speed calculating means for calculating a step number converted moving speed by multiplying the detected step period by a step length;
A moving direction detecting means for detecting a traveling direction on the ground surface by an output of the rate signal correcting means;
If a vibration component is detected when the inertial movement speed of the pedestrian from which the gravitational acceleration component has been removed is detected , the step conversion movement speed must be selected and output, and the vibration component must be detected. And a moving speed selecting means for selecting and outputting the inertial moving speed or its changing speed.
[0010]
According to the present invention, the direction of the ground surface (the direction of gravitational acceleration) is detected by the triaxial acceleration detecting means, and the posture held by the pedestrian moving speed / direction detecting device itself is detected. Then, by detecting the vertical vibration caused by the walking of the pedestrian by the three-axis acceleration detecting means, and analyzing the vibration component, the walking cycle (time required for taking one step) is determined. To detect. By multiplying the step period by the step length, the step-converted moving speed is calculated.
[0011]
Then, by using the direction of the ground surface detected by the triaxial acceleration detection means as the initial value of the triaxial rate sensor, when a pedestrian is making a sudden exercise or using a vehicle Even in the case where an error occurs in the output of the three-axis rate detection means such as the above, the moving direction on the ground surface can be detected.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 is a block diagram showing a configuration of a pedestrian moving distance / direction detecting means 10 as an example for detecting a moving distance and moving direction (moving direction) of a pedestrian. In addition, the route guidance apparatus for pedestrians can be comprised using the movement distance and direction detection means 10 for pedestrians of this example of FIG.
[0014]
FIG. 2 is a block diagram showing the configuration of the stride setting means 12 as an example for setting the stride of a pedestrian.
[0015]
FIG. 3 is a block diagram showing a configuration of inertial speed detection means 14 as an example for detecting the pedestrian's inertial movement speed.
[0016]
4 is a combination of the pedestrian movement distance / direction detection means 10 of FIG. 1 with the stride setting means 12 of FIG. 2 and the inertia speed detection means 14 of FIG. The structure of the pedestrian movement distance / direction detection means 17 including the
[0017]
The pedestrian moving distance / direction detecting means 10 shown in FIG. 1 includes a triaxial acceleration sensor 16 as means for detecting orthogonal triaxial acceleration and a triaxial rate sensor 18 as means for detecting orthogonal triaxial rates. have.
[0018]
The pedestrian movement distance / direction detection means 10 includes a gravitational acceleration direction detection means (gravity direction detection means) 20 connected to the output side of the triaxial acceleration sensor 16, a triaxial rate sensor 18, and a gravitational acceleration direction detection. Gravity acceleration direction tracking means 22 having inputs connected to the output sides of the means 20 is provided.
[0019]
Further, the pedestrian movement distance / direction detection means 10 includes an acceleration signal correction means 24 whose inputs are connected to the output side of the triaxial acceleration sensor 16 and the gravitational acceleration direction tracking means 22, a triaxial rate sensor 18, and a gravitational acceleration. A rate signal correction unit 26 having an input connected to the output side of the direction tracking unit 22 is provided.
[0020]
Furthermore, the pedestrian moving distance / direction detecting means 10 has an input connected to the output side of the acceleration signal correcting means 24 and a step period detecting means 30 to which a clock is supplied from the clock generating means 28, and a step period. Connected to the output side of the detecting means 30, a moving speed calculating means 32 to which a stride (also referred to as a stride signal or stride data) is supplied, and a moving direction detecting means connected to the output side of the rate signal correcting means 26. 34.
[0021]
The pedestrian moving distance / direction detecting means 10 shown in FIG. 1 is basically configured as described above. Next, the operation will be described. Note that a microcomputer is mounted on each component constituting the moving distance / direction detecting means 10 for pedestrians as necessary, and the following operations are performed by processing by the computer.
[0022]
The triaxial acceleration sensor 16 detects the acceleration in each of the x, y, and z directions according to the movement of the pedestrian, and the acceleration signals (also simply referred to as acceleration) Gx0, Gy0, Gz0 (m / s ² ) is output. The triaxial rate sensor 18 detects the rate in each axial direction according to the movement of the pedestrian, and outputs rate signals (also simply referred to as rates) Rx0, Ry0, Rz0 (rad / s) of each axis.
[0023]
The gravitational acceleration direction detecting means 20 extracts an acceleration component due to gravity from the triaxial acceleration signals Gx0, Gy0, Gz0, and outputs the direction as a gravitational acceleration direction signal g (m / s ² ). In this case, the gravitational acceleration direction is detected when it is determined that the amplitude of at least one of the triaxial acceleration signals Gx0, Gy0, and Gz0 changes periodically, for example, when a pedestrian walks. If it is determined that the remaining DC component from which the relatively high-frequency vibration component has been removed can be separated as a gravitational acceleration component by low-pass filter processing or the like. Further, when the acceleration signal Gx0, Gy0, Gz0 does not include a vibration component, such as when the pedestrian is stopped, the obtained acceleration signal may be identified as the gravitational acceleration component.
[0024]
The gravitational acceleration direction tracking means 22 sets the triaxial rate signals Rx0, Ry0, Rz0 when the gravitational acceleration direction detection means 20 succeeds in detecting the gravitational acceleration direction signal g as initial values, and then obtains each axis obtained thereafter. By processing the rate signals Rx0, Ry0, Rz0 as the inclination of the pedestrian movement distance / direction detection means 10 (inclination with respect to the ground surface), the pedestrian movement distance / direction detection means 10 is The state (inclination) is calculated and the calculation result is output as a correction amount (correction value).
[0025]
The acceleration signal correction means 24 converts the acceleration signals Gx0, Gy0, Gz0 of each axis into triaxial acceleration signals Gx, Gy, Gz for the ground surface using the correction value output from the gravitational acceleration direction tracking means 22. Output.
[0026]
Similarly, the rate signal correction means 26 uses the correction value output from the gravitational acceleration direction tracking means 22 to convert the rate signals Rx0, Ry0, Rz0 of each axis into the triaxial rate signals Rx, Ry, Rz for the ground surface. Convert and output.
[0027]
The clock generation means 28 generates a clock having a constant period (for example, 0.2 ms) for detecting the walking period of the pedestrian. The step period detection means 30 uses, for example, vibration components (up and down) from the triaxial acceleration signals Gx, Gy, and Gz output from the acceleration signal correction means 24 and converted into acceleration motion in the ground surface direction by high-pass filtering. Component), and the time required for the pedestrian to step one step at a time from the separated vibration component cycle is detected by counting the number of clocks of the predetermined cycle and converting the time, and the step cycle (step cycle) Signal).
[0028]
The moving speed calculating means 32 multiplies the step period detected by the step period detecting means 30 by the set step length of the user (pedestrian) or a default step length, thereby calculating the moving speed (movement speed signal). calculate.
[0029]
The movement direction detection means 34 detects the rotation angle about the vertical axis in the direction of gravitational acceleration from the three-axis rate signals Rx, Ry, Rz converted from the rate motion to the ground surface direction output from the rate signal correction means 26. , Output it as the moving direction.
[0030]
In this case, according to the pedestrian movement distance / direction detection means 10 shown in FIG. 1, the movement distance / direction with respect to the ground surface can be accurately detected regardless of the pedestrian's carrying state. In other words, it is possible to detect the posture of the pedestrian movement distance / direction detection means 10 itself. Further, according to the pedestrian movement distance / direction detection means 10 of FIG. 1, it is possible to obtain the movement speed by multiplying the set step length by the step period detected based on the output of the triaxial acceleration sensor 16. Thus, for example, the effect that it is possible to detect the moving speed of a pedestrian even in a situation where radio waves from GPS satellites cannot be received is achieved.
[0031]
The step setting means 12 in the example of FIG. 2 is connected to the GPS receiver 42, the measurement position storage means 44 connected to the output side of the GPS receiver 42, and the output side of the GPS receiver 42, and the step cycle The step count storage means 46 to which the step period is supplied from the detection means 30, the step count calculation means 48 connected to the output side of the step count storage means 46 and the measurement position storage means 44, and the output side of the step length calculation means 48. In addition, a stride storage means 50 to which the step period from the step period detection means 30 is supplied, a measurement position storage means 44 and a measurement timing instruction means 52 connected to the input side of the step count storage means 46 are provided.
[0032]
The stride setting means 12 shown in FIG. 2 is basically configured as described above. Next, the operation will be described. Note that each component constituting the stride setting means 12 is equipped with a microcomputer as necessary, as with each component constituting the pedestrian movement distance / direction detection means 10, and the following processing is performed by the computer. Are performed.
[0033]
The GPS receiver 42 receives radio waves from a GPS satellite through the receiving antenna 43 and detects a measurement position (latitude, longitude, altitude). The measurement position storage means 44 stores the measurement position when the GPS receiver 42 can receive radio waves, calculates the distance between the measurement positions (between two points), and outputs it.
[0034]
The step count storage means 46 stores the number of steps required for movement between any two points (measurement positions) when the GPS receiver 42 can receive radio waves. The number of steps can be calculated by counting the step period signal between the measurement positions.
[0035]
The stride calculation means 48 divides the distance between any two points (measurement positions) stored in the measurement position storage means 44 by the number of steps between any corresponding two points stored in the step count storage means 46. By doing so, the stride can be calculated.
[0036]
The stride storage means 50 stores the calculated stride as a table (lookup table) associated with the step period at that time. For example, a step such as 1 m when the step period is 0.5 seconds is stored in association with a step such as 50 cm when the step period is 1 second. The correspondence table is updated as necessary, and the stride corresponding to the step period is output as the registered stride.
[0037]
The measurement timing instruction unit 52 instructs measurement start timings and measurement end timings at two arbitrary points (measurement positions) used in the measurement position storage unit 44 and the step count storage unit 46.
[0038]
According to the stride setting means 12 in the example of FIG. 2, it is possible to automatically set and update as a registered stride a step difference caused by individual differences of pedestrians as a user or physical condition of pedestrians. The effect of becoming is achieved.
[0039]
In this case, since the stride is stored according to the walking cycle, in other words, the pedestrian walking tempo (normal walking, fast walking, slow walking, running, etc.), the pedestrian walking tempo ( It is possible to output the stride according to the way of walking.
[0040]
Note that the stride set in the moving speed calculation means 32 (see FIG. 1) is not limited to the registered stride according to the example of FIG. 2, but can be arbitrarily set by input setting means not shown.
[0041]
The step length is set by performing so-called map matching (position prediction method) using the pedestrian's movement route and road map (electronic road shape information), and dividing the movement distance on the map by the number of steps. Can also be obtained.
[0042]
The inertial velocity detection means 14 in the example of FIG. 3 uses the triaxial acceleration signals Gx, Gy, Gz output from the acceleration signal correction means 24 and the gravitational acceleration direction signal g output from the gravitational acceleration direction detection means 20. Gravity acceleration removing means 60 to be received, speed change calculating means 62 connected to the output side of gravity acceleration removing means 60 and supplied with a clock from clock generating means 28, and connected to the output side of this speed change calculating means 62 Speed change integration means 64.
[0043]
Next, the operation of the inertia speed detection means 14 will be described. Note that each component constituting the inertial velocity detection means 14 is also equipped with a microcomputer as necessary, and the following operations are performed by computer processing.
[0044]
The gravitational acceleration removing means 60 uses the gravitational acceleration direction signal g obtained by the gravitational acceleration direction detecting means 20 from the corrected acceleration signals Gx, Gy, Gz obtained from the acceleration signal correcting means 24 to obtain a gravitational acceleration component. The removed acceleration signals Gx ′, Gy ′, and Gz ′ are obtained and output. The speed change calculating means 62 detects a speed change by multiplying a predetermined clock period (time) given from the clock generating means 28. The speed change integrating means 64 outputs a value obtained by continuously integrating and averaging the detected speed change values, that is, a so-called moving average value, as an inertial moving speed.
[0045]
FIG. 4 shows an example of inertia, as described above, in which the pedestrian movement distance / direction detection means 10 in FIG. 1 is combined with the stride setting means 12 in FIG. 2 and the inertia speed detection means 14 in FIG. The structure of the pedestrian movement distance / direction detection means 17 including speed detection is shown.
[0046]
In the example of FIG. 4, the movement speed selection means 70 selects the step number converted movement speed obtained by the movement speed calculation means 32 from the step period and the registered stride, and the instantaneous change speed or inertia movement speed obtained by the inertia speed detection means 14. Can be output.
[0047]
Note that the moving speed selection means 70 selects a step-converted moving speed as a moving speed at a relatively low speed where it is difficult to detect a high-accuracy moving speed, so that a sufficiently large acceleration can be obtained. In the moving situation, by selecting the inertial moving speed or the changing speed, the moving speed can be detected with high accuracy in any situation. When selecting the inertial movement speed or the change speed, the movement speed selection means 70 selects the inertial movement speed when the signal level of the inertial movement speed is sufficiently higher than the change speed.
[0048]
More specifically, the speed at which a person as a pedestrian walks using his / her feet is usually about 4 to 8 km / h, and even in the case of running, it is about 20 + α km / h, and a sufficiently large acceleration signal is given. It is difficult to detect. In addition, in the case of movement by foot, there is vibration noise, so that the error increases when the inertial movement speed is selected.
[0049]
Therefore, when the moving speed is higher than a certain level, there is a high possibility that the pedestrian is moving on the vehicle. In the case of movement by a vehicle, a sufficient acceleration signal is often obtained, so the inertial movement speed is selected. Note that the difference between movement by walking and movement by vehicle can be determined as movement by walking if the vibration component is detected when the inertial movement speed is detected.
[0050]
Note that the present invention is not limited to the above-described embodiment, and various configurations can be adopted without departing from the gist of the present invention.
[0051]
【The invention's effect】
As described above, according to the present invention, since the posture of the pedestrian movement speed / direction detection device can be detected, the movement speed / direction can be set regardless of the pedestrian's carrying state. The effect that it can be detected is achieved.
[0052]
Further, according to the present invention, since the pedestrian's vertical movement is detected using the three-axis acceleration detecting means and the rate detecting means, and the moving direction is detected, the GPS receiver can be used without using the GPS receiver. The effect that the moving speed can be obtained from the vertical movement cycle is achieved.
[0053]
Further, when a GPS receiver is used, the stride can be calibrated, and the effect that the moving speed can be calculated more accurately is achieved.
[0054]
When configured to be able to calibrate the stride, an effect is achieved that it becomes possible to set a stride according to individual differences among users.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration example of a pedestrian moving distance / direction detecting means for detecting a moving distance and a moving direction (moving direction) of a pedestrian.
FIG. 2 is a block diagram showing a configuration example of stride setting means for setting the stride of a pedestrian.
FIG. 3 is a block diagram showing a configuration example of inertia speed detection means for detecting the inertial movement speed of a pedestrian.
4 is a pedestrian movement distance / direction including detection of inertial speed in which the pedestrian movement distance / direction detection means of FIG. 1 is combined with the stride setting means of FIG. 2 and the inertial speed detection means of FIG. 3; It is a block diagram which shows the structural example of a detection means.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10, 17 ... Movement distance and direction detection means 12 for pedestrians 12 ... Stride setting means 14 ... Inertia speed detection means 16 ... 3-axis acceleration sensor 18 ... 3-axis rate sensor 20 ... Gravity acceleration direction detection means 22 ... Gravity acceleration direction tracking means 24 ... Acceleration signal correcting means 26 ... Rate signal correcting means 30 ... Step period detecting means 32 ... Moving speed calculating means 34 ... Moving direction detecting means

Claims (4)

Three-axis acceleration detection means;
3-axis rate detection means;
A gravitational acceleration direction detecting means for detecting a gravitational acceleration direction from an output of the triaxial acceleration detecting means;
Gravity direction tracking means for calculating a correction value from the output of the triaxial rate detection means, with the gravitational acceleration direction obtained by the gravitational acceleration direction detection means as an initial gravitational acceleration direction;
Acceleration signal correcting means for correcting the output of the triaxial acceleration detecting means based on the correction value;
Rate signal correction means for correcting the signal of the triaxial rate detection means based on the correction value;
Detecting a vertical vibration component with respect to the ground surface from the output of the acceleration signal correcting means, and detecting a walking cycle of a pedestrian as a walking cycle;
A moving speed calculating means for calculating a step number converted moving speed by multiplying the detected step period by a step length;
A moving direction detecting means for detecting a traveling direction on the ground surface by an output of the rate signal correcting means;
If a vibration component is detected when the inertial movement speed of the pedestrian from which the gravitational acceleration component has been removed is detected, the step conversion movement speed must be selected and output, and the vibration component must be detected. For example, a pedestrian movement speed / direction detection device comprising: movement speed selection means for selecting and outputting the inertial movement speed or a change speed thereof.   2. The apparatus according to claim 1, wherein the stride used by the moving speed calculating means is obtained by dividing the moving distance obtained by using the GPS receiver by the number of steps required to walk the moving distance. A pedestrian movement speed / direction detection device characterized by the above.   2. The apparatus according to claim 1, wherein the stride used by the moving speed calculation means is obtained by applying a position prediction method using road shape information to a moving distance and a moving direction obtained using a GPS receiver. A pedestrian movement speed / direction detection device characterized in that the movement distance obtained is obtained by dividing the movement distance by the number of steps required to walk.   The apparatus according to claim 1, wherein a gravitational acceleration removing unit that removes the gravitational acceleration component from an output of the acceleration signal correcting unit based on the gravitational acceleration direction; Speed change calculation means for calculating the change speed by multiplying the output by the step period; and speed change integration means for calculating the inertial movement speed by continuously integrating and averaging the change speed. A pedestrian movement speed / direction detection device characterized by that.

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