WO2007105640A1

WO2007105640A1 - Contact detector and contact detection method

Info

Publication number: WO2007105640A1
Application number: PCT/JP2007/054690
Authority: WO
Inventors: Idaku Ishii; Kenkichi Yamamoto
Original assignee: National University Of Corporation Hiroshima University
Priority date: 2006-03-10
Filing date: 2007-03-09
Publication date: 2007-09-20
Also published as: JP4810658B2; JP2007240455A

Abstract

A tapping counter (1) is a detector for detecting contact of a finger tip (20) with a plate (30), and comprises a photography section (11) for photographing the finger tip (20) and the plate (30), a distance measuring section (13) for measuring a first time series variation in distance from the finger tip (20) to the plate (30) based on the positions thereof in an image photographed at the photography section (11), a high-pass filter (14) for extracting time series variation in frequency components of the cut-off frequency or above among the first time series variation measured at the distance measuring section (13) as second time series variation, and a section (15) for detecting contact of the finger tip (20) with the plate (30) when the second time series variation extracted by the high-pass filter (14) exceeds a threshold.

Description

Specification

Contact detection device and contact detection method

Technical field

The present invention relates to a contact detection device and a contact detection method for detecting contact between an object and a contact target object.

Background art

[0002] In recent years, various types of human interfaces in information devices have progressed and are used as various partial force interfaces of the human body. In particular, active research is being carried out using a finger that can move at a high speed and at a high speed according to the human intention as an interface. For example, Non-Patent Document 1 describes a device in which a sensor for detecting acceleration is attached to a fingertip. As shown in Non-Patent Document 1, when a sensor is directly attached to a fingertip, there is an advantage that desired information on the fingertip can be easily measured.

Non-Patent Document 1: Koji Tsukada, Michiaki Yasumura, Ubi-Finger, Research on Mopile Oriented Giestier Input Device, IPSJ Transactions, Vol 43, No. 12, pp. 3675-3684, 2002 Disclosure of Invention

Problems to be solved by the invention

[0003] In the technique of mounting the sensor directly on the object to be detected while applying force, for example, a sensor with a large scale may interfere with the operation of the object to be detected. There is a point. Furthermore, when the object to be detected is, for example, a part of the human body, there is a problem in that the human being feels uncomfortable by attaching the sensor to the body.

[0004] Therefore, the present invention provides a technique capable of detecting desired information for an object to be detected without attaching a sensor to the object to be detected. Specifically, the present invention provides a contact that can detect whether or not an object can be contacted with the target object without attaching a sensor that detects that the object contacts the target object. An object is to provide a detection device and a contact detection method.

Means for solving the problem As a result of intensive studies, the present inventors have found that a high-frequency component is present in a time-series change amount with respect to the distance to the object force contact object at the moment when the object and the contact object are in contact with each other. It was found to occur temporarily. Furthermore, we have found that the magnitude of the generated high-frequency component is proportional to the impact force at the moment when the object and the object to be contacted contact each other. The present invention has been made based on these new findings.

[0006] That is, the contact detection device according to the present invention is a contact detection device that detects contact between an object and a contact target object, and includes a photographing unit that photographs the object and the contact target object, and a photographing unit that captures images. Distance measuring means for measuring a first time-series change amount, which is a time-series change amount of the distance from the object to the contact target object, based on the positions of the object and the contact target object in the captured image, and a distance measurement means A high-pass filter that extracts a time-series change amount of a frequency component that is equal to or higher than a predetermined cutoff frequency as a second time-series change amount from the first time-series change amount measured by It is characterized by comprising contact detection means for detecting contact between an object and a contact target object when the time-series change amount exceeds a predetermined threshold value.

[0007] In addition, the contact detection method according to the present invention is a contact detection method for detecting contact between an object and a contact target object, wherein a photographing unit photographs the object and the contact target object, and a distance. Based on the position of the object and the object to be touched in the image captured in the shooting step, the measuring means calculates the first time-series change amount, which is the time-series change amount of the distance to the contact target object. The distance measurement step to be measured and the high-pass filter indicate the time-series change amount of the frequency component above the predetermined cutoff frequency in the first time-series change amount measured by the distance measurement means as the second time-series change amount. The high-pass filtering step and the contact detection means extract the object and the contact target when the second time series change amount extracted in the no-pass filtering step exceeds a predetermined threshold! object It is characterized in that it comprises a contact detection step of detect contact with.

[0008] According to such a contact detection apparatus and contact detection method of the present invention, the distance measuring means measures the first time-series change amount of the distance to the object to be contacted as well as the object force. Next, the high-pass filter removes the low-frequency component below the predetermined cutoff frequency and extracts the second time-series change amount, which is a set of high-frequency components in the first time-series change amount. Put out. Here, the high frequency component is found in the time-series change amount with respect to the distance to the object force contact target object at the moment when the present inventors have found that the object and the contact target object are in contact with each other. Focus on the temporary occurrence. That is, when the second time-series change amount of only the high-frequency component exceeds a predetermined threshold value, the contact detection means detects that there is contact between the object and the target object. Can do.

Thus, in the contact detection device and the contact detection method of the present invention, for example, a contact detection sensor is attached to the object for the purpose of detecting contact between the object and the object to be contacted. I do not. Therefore, according to the present invention, it is possible to detect contact between an object and a contact target object, and it is possible to prevent, for example, a contact detection sensor attached to the object from hindering the operation of the object. .

[0010] Further, the contact detection device measures a value proportional to the second time-series change amount extracted by the high-pass filter as a value representing a collision force when the object and the contact target object contact each other. Is further provided.

[0011] Further, in the contact detection method, when the collision force measuring means makes a contact between the object and the contact target object, a value proportional to the second time-series change amount extracted in the no-pass filtering step. The method further comprises a collision force measurement step of measuring as a value representing the collision force.

[0012] Here, in the time series change amount with respect to the distance from the object to the contact object, the magnitude of the generated high frequency component was found by the present inventors, that is, the object and the contact object. Focus on the fact that it is proportional to the impact force at the moment of contact. That is, the collision force measuring means can detect a predetermined value proportional to the second time-series change amount as a collision force generated when the object and the contact target object come into contact with each other.

[0013] Further, in the contact detection device, an arbitrary sign for indicating the position of the object is provided on the object to be photographed by the photographing means, the photographing means photographs the sign, and the distance measuring means includes The first time-series change amount, which is a time-series change amount of the distance from the sign to the object to be touched, is measured based on the position of the sign taken by the photographing means in the photographed image.

[0014] In addition, according to the contact detection method, the object to be imaged in the imaging step is provided with an arbitrary mark for indicating the position of the object, and the imaging unit in the imaging step. The distance measurement means in the distance measurement step is a time-series change amount of the distance from the sign to the contact target object based on the position of the sign captured in the shooting step in the captured image. It is characterized by measuring the first time series change.

[0015] In this case, a sign that is smaller and lighter than the object can be used as the sign indicating the position of the object. For this reason, for example, the captured image force also reduces the amount of calculation required for image recognition by recognizing the position of the sign instead of recognizing the position of the object. A result equivalent to that of recognition can be obtained.

[0016] In the contact detection device, the predetermined cutoff frequency in the high-pass filter is 40 hertz. In the contact detection method, the predetermined cutoff frequency in the high-nos filtering step is 40 hertz.

[0017] In this way, by setting the cut-off frequency to 40 Hertz, it is possible to detect contact extremely efficiently, particularly when the object is a part corresponding to a human finger or a human finger in a robot. it can. In other words, since the high frequency component generated when the human finger or the part corresponding to the human finger in the robot comes into contact with the contact target object appears clearly in the second time series variation, the contact detection means It is possible to reliably detect whether or not a corresponding part of a human finger or robot is in contact with the object to be contacted.

[0018] In the contact detection device, the predetermined threshold value in the contact detection means is 0.5 mm. In the contact detection method, the predetermined threshold value in the contact detection step is 0.5 mm.

[0019] In this way, by setting the threshold value to 0.5 mm, it is possible to detect contact very efficiently, particularly when the object is a part corresponding to a human finger or a human finger in a mouth bot. be able to. In other words, the contact detection means can ignore minute high-frequency components that can be generated when the corresponding part of the human finger or robot is not in contact with the object to be touched. It is possible to reliably detect whether or not the part and the contact object are in contact with each other.

The invention's effect [0020] According to the present invention, it is possible to detect whether or not a contact between the object and the contact target object can be detected without mounting a sensor that detects that the object is in contact with the contact target object. Brief Description of Drawings

FIG. 1 is a schematic configuration diagram of a tapping counter 1 according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a marker 21 provided on a fingertip 20.

FIG. 3 is a diagram for explaining the positional relationship among a fingertip 20, a plate 30, and a photographing unit 11.

FIG. 4 is a diagram showing a first time-series change amount of the distance between the fingertip 20 and the board 30.

FIG. 5 is an enlarged view of FIG. 4 along the time axis.

FIG. 6 is a diagram showing a first time-series change amount of the distance between the fingertip 20 and the board 30.

FIG. 7 is an enlarged view of FIG. 6 along the time axis.

FIG. 8 is a diagram showing a second time-series change amount of the distance between the fingertip 20 and the board 30.

FIG. 9 is a diagram showing a second time-series change amount of the distance between the fingertip 20 and the board 30.

FIG. 10 is a flowchart showing the operation of the tapping counter 1.

FIG. 11 is a diagram showing a result of an operation performed by the tapping counter 1.

FIG. 12 is a diagram showing a result of an operation performed by the tapping counter 1.

FIG. 13 is a schematic configuration diagram of a collision force measuring device 2 according to a second embodiment of the present invention.

FIG. 14 is a flowchart showing the operation of the collision force measuring apparatus 2.

FIG. 15 is a diagram showing a result of an operation performed by the collision force measuring apparatus 2;

Explanation of symbols

[0022] 1 ... Tapping counter, 2 ... Collision force measuring device, 20 ... Fingertip, 21 ... Marker, 30 ... Plate, 11 ... Shooting unit, 12 ... Control unit, 13 ... Distance measuring unit 14 ... High-pass filter, 15 ... Contact detector, 16 ... Collision force measuring unit.

BEST MODE FOR CARRYING OUT THE INVENTION

[0023] The findings of the present invention can be readily understood by considering the following detailed description with reference to the accompanying drawings shown for illustration only. Subsequently, embodiments of the present invention will be described with reference to the accompanying drawings. Where possible, the same parts are denoted by the same reference numerals, and redundant description is omitted. [0024] [First Embodiment]

A tapping counter 1 will be described as a first embodiment of a contact detection device and a contact detection method according to the present invention. The tapping counter 1 counts the number of times the fingertip 20 has tapped the surface of the plate 30 without attaching a contact detection sensor or the like to the fingertip 20. First, the configuration of the tapping counter 1 will be described with reference to FIGS. 1 to 3 show a fingertip (object) 20 as a contact detection target, a plate (contact target object) 30 as a contact target of the fingertip 20, and an imaging unit (imaging means) 11 and a control unit as a contact detection device. 12 is a diagram for explaining a configuration of a tapping counter 1 including 12.

As shown in FIGS. 1 and 2, the fingertip 20 that is the target of contact detection in the first embodiment is provided with a marker (marker) 21 for indicating the position of the fingertip 20. This marker 21 is smaller and lighter than a finger and has a higher recognition rate in image recognition. In the first embodiment, for example, a light ball with a diameter of 5 mm is used. As will be described later, the tapping counter 1 recognizes the position of the marker 21 instead of directly recognizing the image of the position of the fingertip 20 with respect to the captured image power.

[0026] As shown in Figs. 1 and 3, the plate 30 in the first embodiment is an object to be touched by the fingertip 20, and is basically made of iron with a wall thickness of 2.9mm. It is a flat plate. For this reason, the board 30 becomes a background in the photographed image, and it is not necessary for the tapping counter 1 to recognize up to the board 30 for each photographing frame. That is, in the first embodiment, the coordinates of a predetermined part of the captured image are used as the position information of the plate 30.

The imaging unit 11 shown in FIGS. 1 and 3 extracts position information (position coordinates) of the marker 21 in the image obtained by imaging the marker 21 and the plate 30 in real time. Is, for example, a normal high-speed vision camera having a CMOS image sensor with a spatial resolution of 1280 X 1024 pixels. The photographing unit 11 outputs the extracted position information of the marker 21 to the control unit 12.

The control unit 12 shown in FIG. 1 detects contact between the fingertip 20 and the plate 30 based on the position information of the marker 21 and the plate 30. In the first embodiment, the control unit 12 includes a storage unit such as a CPU, a memory, a communication interface, and a hard disk as a physical component. A computer system having a display unit such as a computer.

[0029] The positional relationship among the fingertip 20, the board 30, and the photographing unit 11 will be described in detail with reference to FIG. As shown in FIG. 3, in the first embodiment, it is assumed that the fingertip 20 moves on a plane about 400 mm forward as viewed from the photographing unit 11. The imaging unit 11 is disposed 80 mm above the surface of the plate 30 and keeps the optical axis horizontal with respect to the plate 30. The field of view of the shooting unit 11 is set to 288mm X 230mm near the 20 position of the tip, and is set to a spatial resolution of 0.225mm per pixel. The position of the fingertip 20 can be calculated using the conventional image recognition technique by tracking the marker 21 attached to the fingertip 20 by the imaging unit 11 as described above. In the first embodiment, the imaging unit 11 tracks the marker 21 of the fingertip 20 using, for example, a 64 × 64 pixel window, and calculates the position of the center of gravity to obtain the position of the fingertip 20. It is preferable to change the measurement rate at the 20 positions of the fingertip according to the number of target fingers, for example, 900 [fps] for one finger, and 470 [fps for two, three, and four fingers, respectively. ], 390 [fps], and 280 [fps]. In the first embodiment, in order to simplify the explanation, the number of target fingers is one and the measurement rate at the fingertip 20 position is 900 [fps]. As described above, the position of the plate 30 is set to the coordinates of a predetermined portion determined in advance in the captured image.

Returning to FIG. 1, the control unit 12 of the tapping counter 1 includes a distance measurement unit (distance measurement unit) 13, a high-pass filter 14, and a contact detection unit (contact detection unit) 15. Hereafter, each component which comprises the control part 12 is demonstrated in detail, referring further FIGS. 4-9.

[0031] The distance measurement unit 13 obtains the distance from the fingertip 20 to the plate 30 based on the position information of the plate 30 and the position information of the marker 21 input from the imaging unit 11, and calculates the time series of the distances. It measures the amount of change in the first time series, which is the amount of change. 4 to 7 are diagrams showing the first time-series change amount of the distance measured by the distance measuring unit 13. In FIGS. 4 to 7, the height of the marker 21 with the height of the upper surface of the plate 30 as Omm (reference height) is expressed as the distance.

[0032] FIG. 4 shows the first time-series change amount for one second when the fingertip 20 repeats the tapping operation without contact between the fingertip 20 and the plate 30. FIG. 5 is an enlarged view of FIG. 4 on the time axis, and shows the first time-series change amount for 0.2 seconds when there is no contact between the fingertip 20 and the board 30. As shown in Fig. 4 and 5, when there is no contact between fingertip 20 and plate 30 The first time-series change amount appears as a smooth curve without high frequency components.

FIG. 6 shows a first time-series change amount for one second when the tapping operation is repeated while the fingertip 20 is in contact with the plate 30. FIG. 7 is an enlarged view of FIG. 6 on the time axis, and shows the first time series change amount in 0.2 seconds when the fingertip 20 and the board 30 are in contact with each other. As can be seen in FIGS. 6 and 7, when the fingertip 20 and the plate 30 are in contact with each other, a temporary distortion occurs around a height of 10 mm corresponding to the thickness of the finger. Thus, it can be seen that a high frequency component is generated in the first time-series variation at the moment when the fingertip 20 contacts the plate 30. The distance measurement unit 13 outputs the first time series change amount as shown in FIGS. 4 to 7 to the high pass filter 14.

[0034] The no-pass filter 14 removes a low frequency component less than a predetermined cutoff frequency from the first time-series variation input from the distance measuring unit 13, and a frequency component equal to or higher than the cutoff frequency. Is extracted as the second time-series change amount. That is, the second time series variation extracted by the no-pass filter 14 is a set of high frequency components equal to or higher than the cutoff frequency extracted from the first time series variation force. In the first embodiment, the cutoff frequency is 40 hertz.

[0035] FIG. 8 shows the result of the high-pass filter 14 filtering the first time-series variation shown in FIGS. 4 and 5, that is, the second case where there is no contact between the fingertip 20 and the plate 30. It is a figure which shows a time series change amount. Since the high frequency component is not generated in the first time series variation shown in Figs. 4 and 5, almost no high frequency component appears in the second time series variation shown in Fig. 8.

FIG. 9 shows the result of the high-pass filter 14 filtering the first time-series variation shown in FIGS. 6 and 7, that is, the second result when the fingertip 20 and the plate 30 are in contact with each other. It is a figure which shows a time series change amount. Along with the time when the high-frequency component (distortion) occurs in the first time-series variation shown in Figs. 6 and 7, a large amount of high-frequency component is also generated in the second time-series variation shown in Fig. 8. The no-pass filter 14 outputs the second time-series change amount as shown in FIGS.

The contact detection unit 15 detects the contact between the fingertip 20 and the plate 30 by comparing the second time-series change amount input from the high-pass filter 14 with a predetermined threshold value. Specifically, the contact detector 15 detects the fingertip 20 when the second time-series change amount is equal to or greater than a predetermined threshold. When the second time-series change amount is less than a predetermined threshold value, it is detected that there is no contact between the fingertip 20 and the plate 30. In the first embodiment, the predetermined threshold is 0.5 mm, and is indicated by a dotted line in FIGS.

In FIG. 8, there is no case where the second time-series change amount is equal to or greater than the threshold value of 0.5 mm, and therefore the contact detection unit 15 does not detect contact between the fingertip 20 and the plate 30. On the other hand, in FIG. 9, the second time series change amount exceeds the threshold value seven times in one second, and the contact detection unit 15 detects that the contact between the fingertip 20 and the plate 30 has occurred seven times. .

[0039] Next, the operation (contact detection method) of the tapping counter 1 of the first embodiment will be described with reference to FIGS. FIG. 10 is a flowchart showing the operation of the tapping counter 1. FIG. 11 is a diagram for explaining the result of the operation performed by the tapping counter 1 when the fingertip 20 performs the tapping operation nine times in 2 seconds. Fig. 12 shows the operation performed by tapping counter 1 when performing tapping motion twice and 4 feint motions (blank motion where fingertip 20 and board 30 do not contact) in 20 finger ^ seconds. It is a figure for demonstrating the result of.

First, the photographing unit 11 extracts the position information of the marker 21 in the image obtained by photographing the marker 21 and the plate 30 in real time. The imaging unit 11 outputs the extracted position information of the marker 21 to the distance measuring unit 13 (imaging step, step S1 in FIG. 10).

[0041] Next, the distance measurement unit 13 obtains the distance from the fingertip 20 to the plate 30 based on the position information of the plate 30 and the position information of the marker 21 input from the imaging unit 11, and the distance Measure the first time series change, which is the time series change of. (A) in FIG. 11 and (a) in FIG. 12 show the first time-series change amount measured by the distance measurement unit 13. The distance measurement unit 13 outputs the measured first time-series change amount to the high-pass filter 14 (distance measurement step, step S2 in FIG. 10).

[0042] Next, the high-pass filter 14 removes a low-frequency component having a cut-off frequency of less than 40 hertz from the middle of the first time-series change amount input from the distance measurement unit 13, and the cut-off frequency 40 Extract the time-series variation of frequency components above hertz as the second time-series variation. (B) in FIG. 11 and (b) in FIG. 12 show the second time-series variation extracted by the high-pass filter 14. The no-pass filter 14 sends the extracted second time series change amount to the contact detection unit 15. Output (filtering step, step S3 in Fig. 10).

Next, the contact detection unit 15 detects contact between the fingertip 20 and the plate 30 by comparing the second time-series change amount input from the high-pass filter 14 with a threshold value of 0.5 mm. Specifically, the contact detection unit 15 detects the contact between the fingertip 20 and the plate 30 when the second time series change amount is a threshold value of 0.5 mm or more, and the second time series change amount. If the threshold is less than 0.5 mm, it is detected that there is no contact between the fingertip 20 and the plate 30 (contact detection step, step S4 in FIG. 10).

[0044] (c) in FIG. 11 shows that when the fingertip 20 performs nine tapping operations in 2 seconds, the contact detection unit is based on the second time-series change amount shown in (b) in FIG. 15 indicates the number of times counted. The contact detection unit 15 counts the contact at the moment when the second time series change amount exceeds the threshold value 0.5 mm, and counts 9 times in 2 seconds. This result coincides with the number of times the fingertip 20 actually touches the board 30, and it can be said that the tapping counter 1 accurately counted the contact between the fingertip 20 and the board 30.

[0045] On the other hand, (c) of FIG. 12 shows the second time series shown in (b) of FIG. 12 when the fingertip 20 performs two tapping operations and four feint operations in 2 seconds. Based on the amount of change, indicates the number of times the contact detection unit 15 forces S were counted. The contact detection unit 15 counts the contact at the moment when the second time-series change amount exceeds the threshold value 0.5 mm, and counts twice in 2 seconds according to the moment of contact. This result coincides with the number of times and time when the fingertip 20 actually touches the board 30, and the tabbing counter 1 accurately counts the contact between the fingertip 20 and the board 30 even when the fingertip 20 is in a faint motion. Yes, I get.

Subsequently, the operation and effect of the first embodiment will be described. According to the tapping counter 1 of the first embodiment, for example, even if a contact detection sensor is not attached to the fingertip 20 for the purpose of detecting contact between the fingertip 20 and the plate 30, FIGS. As shown in FIG. 5, the contact between the fingertip 20 and the plate 30 can be accurately detected. For this reason, for example, it is possible to prevent the contact detection sensor attached to the fingertip 20 from hindering the operation of the fingertip 20. Furthermore, for example, it is possible to prevent a contact detection sensor attached to a finger from interfering with the movement of the finger and causing a human to feel uncomfortable.

[0047] In addition, the marker 21 in the first embodiment represents the position of the fingertip 20, and the fingertip Use a smaller and lighter one than 20. For this reason, for example, the photographed image force also recognizes the position of the fingertip 20 while recognizing the position of the sign instead of recognizing the position of the fingertip 20 while reducing the amount of calculation required for image recognition. The result is equivalent to the case of direct recognition.

[0048] Further, in the tapping counter 1 of the first embodiment, by setting the cutoff frequency to 40 Hz, the high frequency component generated when the fingertip 20 and the plate 30 are in contact with each other is It appears clearly in the series variation. For this reason, the contact detection unit 15 can reliably detect whether or not the fingertip 20 and the plate 30 are in contact with each other.

[0049] In addition, in the tapping counter 1 of the first embodiment, by setting the threshold value to 0.5 mm, a fine high frequency component that can be generated when the fingertip 20 and the plate 30 are not in contact with each other is set. Minutes can be ignored. For this reason, the contact detection unit 15 can reliably detect whether or not the fingertip 20 and the plate 30 are in contact with each other.

[0050] While the preferred first embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the first embodiment.

[0051] For example, in the first embodiment described above, a human finger is an object to be contact-detected, but the portion corresponding to a human finger in a robot that is not limited to this is a contact-detection target. It is good also as an object. Even in this case, for example, a contact detection sensor is not attached to the part in order to detect contact between the part corresponding to the human finger in the robot and the plate 30. Therefore, for example, it is possible to prevent a contact detection sensor attached to the part from hindering the operation of the part.

[0052] Furthermore, in the first embodiment, the basically non-moving plate 30 is an object to be touched by the fingertip 20, but any moving object is an object to be touched by the fingertip 20. It is also possible. In this case, the photographing unit 11 extracts the position information in the photographed image of the object to be touched by the fingertip 20 in real time and outputs it to the distance measuring unit 13. Then, the distance measuring unit 13 obtains the distance from the fingertip 20 to the contact target object based on the position information of the contact target object and the marker 21 input from the imaging unit 11.

[0053] [Second Embodiment]

As a second embodiment of the contact detection device and the contact detection method according to the present invention, a collision force measurement is performed. The fixed device 2 will be described. The collision force measuring device 2 includes all the elements constituting the tapping counter 1 in the first embodiment, and the respective elements are arranged in an equivalent positional relationship (see FIG. 3). Means) 16 is provided. The collision force measuring device 2 is a device that measures not only the possibility of contact between the fingertip 20 and the plate 30, but also the collision force at the moment when the fingertip 20 and the plate 30 contact each other. First, the configuration of the collision force measuring device 2 will be described with reference to FIGS.

FIG. 13 is a schematic configuration diagram of the collision force measuring device 2. As shown in FIG. 13, the collision force measurement device 2 includes an imaging unit 11 and a control unit 12, and the control unit 12 includes a distance measurement unit 13, a high-pass filter 14, a contact detection unit 15, and a collision force measurement unit 16. The no-pass filter 14 outputs the extracted second time-series change amount to the collision force measurement unit 16. The collision force measurement unit 16 measures a value proportional to the peak value of the second time-series change amount input from the high-pass filter 14 as a value representing the collision force when the fingertip 20 and the plate 30 are in contact with each other. Is.

The collision force measured by the collision force measurement unit 16 is used for, for example, a virtual instrument including the collision force measurement device 2. In this case, the virtual musical instrument or the like can appropriately determine the volume of the sound source generated by the virtual musical instrument or the sound generation time based on the collision force measured by the collision force measurement unit 16. Furthermore, a virtual musical instrument or the like can appropriately determine the time for generating a sound source based on the contact time detected by the contact detection unit 15.

[0056] The operation of the collision force measuring apparatus 2 of the second embodiment will be described with reference to Figs. FIG. 14 is a flowchart showing the operation of the collision force measuring apparatus 2. Fig. 15 shows that the collision force measurement device 2 performed when the fingertip 20 performed two tapping motions and four feint motions (missing motion in which the fingertip 20 and the plate 30 do not contact) in 2 seconds. It is a figure for demonstrating the result of operation | movement.

First, the photographing unit 11 extracts the position information of the marker 21 in the image obtained by photographing the marker 21 and the plate 30 in real time. The imaging unit 11 outputs the extracted position information of the marker 21 to the distance measuring unit 13 (imaging step, step S1 in FIG. 14).

[0058] Next, the distance measurement unit 13 obtains the distance from the fingertip 20 to the plate 30 based on the position information of the plate 30 and the position information of the marker 21 input from the imaging unit 11, and the distance Measure the first time series change, which is the time series change of. Fig. 15 (a) shows that the distance measurement unit 13 The measured first time series change is shown. The distance measuring unit 13 outputs the measured first time series change amount to the high-pass filter 14 (distance measuring step, step S2 in FIG. 14).

[0059] Next, the high-pass filter 14 removes a low-frequency component having a cutoff frequency of less than 40 Hz from the middle amount of the first time-series change amount input from the distance measuring unit 13, and the cutoff frequency 40 Extract the time-series variation of frequency components above hertz as the second time-series variation. FIG. 15B shows the second time-series change amount extracted by the high-pass filter 14. The high-pass filter 14 outputs the extracted second time-series change amount to the contact detection unit 15 and the collision force measurement unit 16 (filtering step, step S3 in FIG. 14).

Next, the contact detection unit 15 detects the contact between the fingertip 20 and the plate 30 by comparing the second time-series change amount input from the high-pass filter 14 with the threshold value 0.5 mm. Specifically, the contact detection unit 15 detects the contact between the fingertip 20 and the plate 30 when the second time series change amount is a threshold value of 0.5 mm or more, and the second time series change amount. If the threshold is less than 0.5 mm, it is detected that there is no contact between the fingertip 20 and the plate 30 (contact detection step, step S4 in FIG. 14).

[0061] FIG. 15 (c) shows the second time-series change amount shown in FIG. 15 (b) when the fingertip 20 performs two tapping operations and four feint operations in two seconds. Based on this, the number of times the contact detector 15 has counted is shown. The contact detection unit 15 counts the insects at the moment when the second time series change amount exceeds the threshold value of 0.5 mm, and performs the counting twice in 2 seconds, in accordance with the moment of the insects. . This result coincides with the number of times and time when the fingertip 20 actually contacts the board 30, and it can be said that the collision force measuring device 2 accurately counted the contact between the fingertip 20 and the board 30.

Next, the collision force measurement unit 16 represents a collision force when the fingertip 20 and the plate 30 are in contact with a value proportional to the peak value of the second time-series change amount input from the high-pass filter 14. Measured as a value (impact force measurement step, step S5 in Fig. 14).

[0063] (d) of FIG. 15 shows the second time-series change amount shown in (b) of FIG. 15 when the fingertip 20 performs two tapping operations and four feint operations in 2 seconds. Based on this, the collision force measured by the collision force measurement unit 16 is shown. Referring to (b) of Fig. 15, the peak value of the high frequency component generated at about 3.3 seconds is about 4 mm, and the peak value of the high frequency component generated at about 4.7 seconds is about 3mm. Figure 15 (d) shows the impact force measured at about 3.3 seconds. The collision force measured at about 4.7 seconds is 6N. From this result, it is possible that the collision force measurement unit 16 measures the collision force in proportion to the peak value of the generated high frequency component.

[0064] Next, operations and effects of the second embodiment will be described. According to the collision force measurement device 2 of the second embodiment, for example, even if a collision force measurement sensor is not attached to the fingertip 20 for the purpose of measuring the collision force at the time of contact between the fingertip 20 and the plate 30, As shown in FIG. 15, the collision force at the time of contact between the fingertip 20 and the plate 30 can be detected. Therefore, for example, it is possible to prevent the collision force measurement sensor attached to the fingertip 20 from hindering the operation of the fingertip 20. Further, for example, it is possible to prevent a collision force measurement sensor attached to a finger from interfering with the movement of the finger and causing a human to feel uncomfortable.

[0065] While the preferred second embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the second embodiment.

[0066] For example, in the second embodiment described above, a force that makes a human finger an object that is a target of collision force measurement at the time of contact is not limited to this. It is good also as an object used as the object of collision force measurement at the time of contact. Even in this case, for example, a collision force measurement sensor is not attached to the part for the purpose of measuring the collision force between the part corresponding to the human finger and the plate 30 in the mouth bot. For this reason, for example, it is possible to prevent the collision force measurement sensor attached to the part from hindering the operation of the part.

Furthermore, the collision force measuring device 2 in the second embodiment is not limited to a virtual musical instrument, and can be applied as appropriate to, for example, a mouse of a personal computer.

Claims

The scope of the claims

[1] A contact detection device for detecting contact between an object and a contact target object,

Imaging means for imaging the object and the contact target object;

Based on the positions of the object and the contact target object in the image captured by the photographing means, the object force is also measured with a first time series change amount that is a time series change amount of the distance to the contact target object. A distance measuring means;

A high pass filter that extracts a time series change amount of a frequency component equal to or higher than a predetermined cut-off frequency among the first time series change amount measured by the distance measuring means; and a second time series change amount;

Contact detection means for detecting contact between the object and the contact target object when the second time-series change amount extracted by the high-pass filter is equal to or greater than a predetermined threshold value. Contact detection device.

[2] A collision force measurement unit that measures a value proportional to the second time-series change amount extracted by the high-pass filter as a value representing a collision force when the object and the contact target object are in contact with each other. The contact detection device according to claim 1, further comprising:

[3] The object to be imaged by the imaging means is provided with an arbitrary sign for indicating the position of the object,

The photographing means photographs the sign,

The distance measuring unit measures a first time series change amount that is a time series change amount of a distance from the sign to the contact target object based on a position of the sign taken by the photographing means in a photographed image. The contact detection device according to claim 1, wherein the contact detection device is a contact detection device.

[4] The contact detection device according to any one of claims 1 to 3, wherein the predetermined cutoff frequency in the no-pass filter is 40 hertz.

[5] The contact detection device according to any one of [1] to [3], wherein the predetermined threshold value in the contact detection means is 0.5 mm.

[6] A contact detection method for detecting contact between an object and a contact target object,

An imaging step in which the imaging means images the object and the contact target object; The distance measurement means is a first time that is a time-series change amount of the distance from the object to the contact target object based on the position of the object and the contact target object in the image captured in the capturing step. A distance measurement step for measuring a series change amount, and a high-pass filter, for the first time series change amount measured by the distance measurement means, represents a time series change amount of a frequency component equal to or higher than a predetermined cutoff frequency. A high-pass filtering step to extract as the second time series change amount;

A contact detection step of detecting contact between the object and the contact target object when the second time-series change amount extracted in the high-pass filtering step is equal to or greater than a predetermined threshold value. When

A contact detection method comprising:

[7] A value representing a collision force when the object and the contact target object are in contact with a value proportional to the second time-series change amount extracted by the high-pass filtering step. The contact detection method according to claim 6, further comprising a collision force measurement step of measuring as follows.

[8] The object to be imaged in the imaging step is provided with an arbitrary sign for indicating the position of the object,

The photographing means in the photographing step photographs the sign,

The distance measuring means in the distance measuring step is a time-series change amount of the marker force and the distance to the contact target object based on the position of the marker imaged in the imaging step in the captured image. 8. The contact detection method according to claim 6, wherein a time series change amount is measured.

9. The contact detection method according to any one of claims 6 to 8, wherein the predetermined cutoff frequency in the no-pass filtering step is 40 hertz.

10. The contact detection method according to any one of claims 6 to 8, wherein the predetermined threshold value in the contact detection step is 0.5 mm.