JP2009207789A - Method for determining necessity to adjust artificial leg, artificial leg using the same, and adjustment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make even a person without much experience reliably and appropriately recognize an adjustment timing when determining necessity to adjust the artificial leg of multi-stage control. <P>SOLUTION: The use frequency of valve opening with respect to each walking speed indicates a distribution in a Mt. Fuji-like shape in ideal walking to give satisfaction to the user of the artificial leg. When the ability of walking in the user of the artificial leg changes, distortion is found in the distribution in the Mt. Fuji-like shape. Thus, use frequency data of each valve opening in multi-stages is stored, and the stored data are differentiated, and then, converted into use frequency information of each valve opening by differential values. The necessity for adjustment is determined by whether a waveform to be generated by the use frequency information has the distortion being equal to or more than a prescribed value. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a technique for adjusting a prosthetic leg that can be bent and / or extended at a knee part. Specifically, it is useful for knowing an appropriate timing for adjusting a prosthetic leg as the walking ability of a prosthetic leg wearer improves. Technology.

  A typical example of this type of prosthesis is a thigh prosthesis. In the thigh prosthesis, the first component on the thigh side and the second component on the thigh side can be bent and / or extended at the knee portion, and normally, in order to assist the bending and / or extension, It has a pressure or hydraulic fluid pressure control device. As the fluid pressure control device, a piston type including a reciprocating piston, a rotary type including a swing vane, or the like is used. Such a fluid pressure control device is supported between both the first and second constituent members, and functions to provide resistance to, for example, knee bending. The appropriate resistance varies depending on the form of walking. Therefore, it is known that the fluid pressure control device includes a variable control valve that throttles the flow of fluid accompanying bending, and controls the valve opening (that is, the degree of throttling) of the variable control valve according to the walking mode. Yes. Control of the valve opening itself can be easily performed by a technique using an electronic control circuit or a microprocessor.

The valve opening control method includes multiple steps (for example, 5 steps and 10 steps) from the optimal control that performs more subtle control continuously from the slow walking speed to the fast walking speed and from the slow walking speed to the fast walking speed. Multi-stage control is known in which the control threshold value is set by changing the size in steps in each stage. The former optimum control is preferable in terms of high-precision control, but has a drawback that the battery as a power source is consumed very much. On the other hand, the latter multi-step control is a step-wise control, so that the battery consumption is low and the practicability is sufficient for walking control of the artificial leg. The following patent document 1 mentions such optimal control and multi-stage control.
JP-A-6-189993

Multi-stage control can be said to be a more practical control method for the reasons described above. The control characteristic of the valve opening for multi-stage control not only depends on the walking speed, but also depends on the individuality of walking of each prosthetic leg wearer (how to walk differs depending on the person). Therefore, in order to perform the control that each prosthetic leg wearer satisfies, prior to wearing the prosthetic leg, the control data of the valve opening suitable for each wearer's walk is set and given to the electronic control circuit on the prosthetic leg side. It is necessary. The setting is data exchange (that is, communication) between the electronic control circuit on the artificial leg side and the setting device outside the artificial leg. This communication can be performed in a wired form (see Patent Document 1 above) or in a wireless form (see Patent Documents 2 and 3 described below).
JP-A-5-337146 (corresponding to British Patent Publication GB 2268070 A) British Patent Publication GB 2280609 A

However, such setting data of the valve opening is not fixed. Since the walking ability of the prosthetic leg wearer is changed by walking training, it is required to appropriately adjust the setting data in accordance with the change. Accompanying walking training, a prosthetic leg wearer can walk faster. Therefore, adjustment on the side where the walking speed is fast is usually essential. Until now, when judging the timing or degree of adjustment, experts (prosthetic orthotics, physical therapists, etc.) tend to rely on experience and intuition in response to requests from prosthetic wearers. there were. In this regard, Patent Document 4 proposes a method for objectively knowing the timing of adjustment and several adjustment methods. There, the frequency of use of each valve opening based on actual walking is memorized, and the valve corresponding to the slowest walking speed is used when the usage frequency of the valve opening corresponding to the fastest walking speed exceeds a predetermined value. It is understood that the adjustment timing is when the use frequency of the opening is equal to or less than a predetermined value, and the adjustment is performed so as to match objective data of the valve opening-use frequency after the change.
JP 2005-111141 A

  The inventors have repeatedly studied and analyzed the use frequency of the valve opening with respect to each walking speed based on actual walking on a lot of data. As a result, the idea described in Patent Document 4 has a technical significance that it is possible to know the adjustment timing objectively, but it is difficult to grasp the optimum adjustment timing. It has been found that there is a problem that a large amount of data is required (for example, data based on walking exceeding 10,000 steps must be accumulated).

  Then, after reviewing the above-mentioned many data from the viewpoint of the distribution of the frequency of use and further studying them, the following was noticed. In other words, in an ideal walk where the prosthetic leg wearer is satisfied, the frequency of use of the valve opening for each walking speed is a Mt. Fuji distribution (the frequency decreases with increasing distance from the peak, and the decrease decreases with increasing distance from the peak. This is a discovery that when the walking ability of a prosthetic leg wearer changes, distortion will be found in the distribution of Mt. Fuji. Moreover, the point in time when the distortion is observed in such a distribution of Mt. Fuji tends to be located before reaching the timing to be adjusted based on Patent Document 4 described above.

  The present invention has been made in consideration of the results of the above-described studies, and makes it possible for a person who has little experience in adjusting a prosthetic leg to know the timing of adjustment reliably and appropriately. Is an issue.

  In order to solve such a problem, in the present invention, the above-described discovery, that is, “when the walking ability of the prosthetic leg wearer changes (in other words, when adjustment is necessary), the Mt. Fuji distribution is distorted. Utilize “becoming found”.

Therefore, the present invention is a technique for determining or determining whether or not the setting data of the valve opening degree in the artificial leg should be adjusted, and includes the following steps as a determination process.
(A) A step of accumulating multi-stage valve opening use frequency data based on the actual walking of the prosthetic leg wearer (B) A multi-stage use frequency data accumulated in step A is differentiated, Step (C) Converting to usage frequency information of each valve opening by differential value (C) Paying attention to the waveform formed by the usage frequency information of each valve opening by the differential value obtained in step B, the waveform is larger than a predetermined value The process of determining that adjustment is necessary when the condition that there is distortion is satisfied, and determining that adjustment is not necessary when the condition is not satisfied

  Determining whether or not adjustment is necessary in a prosthetic leg is inseparable from making an appropriate adjustment. Therefore, after obtaining the determination that the adjustment is necessary, rather than determining the size of the adjustment and performing the adjustment accordingly, the size of the adjustment determined in relation to the distortion is obtained in advance, and the adjustment is performed. It is preferable to determine whether or not adjustment is necessary depending on whether or not the magnitude of the is greater than or equal to a reference value. This is because the processing for obtaining the walking speed set value and the valve opening can be quickly performed based on the magnitude of the adjustment already obtained. Since the magnitude of the adjustment is related to the magnitude of the distortion, comparing the magnitude of the adjustment with the reference value leads to knowing whether the magnitude of the distortion is equal to or greater than a predetermined value.

Embodiment 1

  The electronic control circuit on the artificial leg side normally includes a CPU having data calculation and processing functions, and a memory for storing data while exchanging data with the CPU. Therefore, each process of A, B, and C of this invention can be performed using CPU and memory which such an artificial leg has. In that case, the prosthetic leg itself has a function of determining whether or not adjustment of the setting data of the valve opening degree is necessary (in other words, a function of notifying the timing of the adjustment). For this reason, it is preferable to provide a notification means on the prosthetic leg to notify the result of the determination. As the notification means, light, sound, vibration, or the like that can be easily caught by a prosthetic leg wearer or an expert can be selected. A typical example of the notification means is a display unit that visually displays the processing result of the electronic control circuit.

Embodiment 2

  When setting the valve opening setting data to the prosthetic leg or adjusting the existing setting data, an external setting device that can communicate with the prosthetic leg side is generally used. Therefore, at least a part of the steps A, B, and C can be executed by an external setting device. For example, the electronic control circuit on the artificial leg side is caused to execute the A process, and the external setting device (this is referred to as an adjusting device in the present invention) is caused to execute the B process and the C process. Therefore, in the second embodiment, the notification means for notifying the determination result will be provided in the adjusting device outside the artificial leg.

Technical significance of differentiating usage frequency data

  In ideal walking, the frequency of use of the valve opening for each walking speed shows the aspect of Mt. Fuji distribution. And when distortion arises in such a Mt. Fuji distribution, adjustment is required to correct the distortion. Therefore, differentiating the usage frequency of the valve opening (this differentiation includes, of course, using a difference method approximating the differentiation) reveals the distortion in the usage frequency distribution. There is significance to make. Therefore, differentiating makes it easier to grasp the distortion in the distribution. Further, in the case of the above-described Patent Document 4, the usage frequency of the valve opening corresponding to the fastest walking speed or the usage frequency of the valve opening corresponding to the slowest walking speed is used for a part of the distribution. Trying to find a change. On the other hand, in the present invention, it is possible to grasp a change in the entire distribution by paying attention to the entire distribution based on the differential value. Thereby, even if it is a person with little experience of adjustment of a prosthetic leg, distortion can be grasped | ascertained correctly and the timing of adjustment can be known reliably and appropriately. As the differential value, a first-order differentiated value, a second-order differentiated value, a third-order differentiated value exceeding the second floor, or a combination of a plurality of these differentiated values can be used. From the viewpoint of easy data processing, processing using a second-order differentiated value is preferable.

  FIG. 1 shows an overall image of a femoral prosthesis 10 to which the present invention is applied. The thigh prosthesis 10 includes a resin socket 20 for inserting a cut stump, a knee joint 30 for obtaining a knee bending-extension function, and a foot 40 serving as a grounding portion. Further, the thigh prosthesis 10 includes an adapter 50 that can be adjusted in length and a rotary joint 52 that can rotate around the axis in order to adapt the length of the prosthesis in the axial direction to the wearer. And the cover 60 of a leg form covers the outer side of those structural members.

  Looking at the knee joint 30, the thigh prosthesis 10 has a knee axis that rotatably connects the first component member (knee member) 310 on the thigh side and the second component member (frame member) 320 on the crus side. 330 is provided. Further, the thigh prosthesis 10 includes a cylinder device 70 as a fluid pressure control device for assisting the bending-extension function. In the case of this embodiment, the fluid pressure control device 70 is an air cylinder device using pneumatic pressure. As the air cylinder device, for example, a known device shown in the specification of USP 5,899,943 can be applied.

  FIG. 2 clarifies the cross-sectional structure of the knee joint 30. Above the inside of the frame member 320 of the knee joint 30 is a sensor 140 including the brake mechanism 12 positioned around the knee shaft 330, the magnet 14m on the knee member 310 side, and the proximity switch 14s on the frame member 320 side. Further, the air cylinder device 70 has a first support point 601 at one end of the piston rod 72 and a second support point 702 at the lower part of a cylindrical cylinder body 74 which is a housing member. The piston rod 72 holds a piston 76 as a partition member inside the cylinder body 74. The piston 76 partitions the inside of the cylinder body 74 into a first chamber 701 and a second chamber 702. When the knee bends and extends, air flows between the first chamber 701 and the second chamber 702. A communication passage that connects the first chamber 701 and the second chamber 702 is provided inside the piston 76 and the cylinder body 74. These connecting passages are parallel to each other. In the middle of the communication passage in the cylinder body 74, there is a variable control valve 80 in which the valve opening degree or the degree of throttle is variable. The variable control valve 80 is a valve for imparting resistance to knee flexion. The greater the opening of the valve, the smaller the resistance to bending, and conversely, the smaller the opening, the greater the resistance to bending.

  The variable control valve 80 is a needle valve, and the opening degree of the valve can be changed by moving the needle in the axial direction. The drive mechanism 90 moves the needle of the variable control valve 80. The drive mechanism 90 includes an electronically controllable stepping motor 92 and a screw portion 94 that converts the rotation of the stepping motor 92 into a linear motion. The needle of the variable control valve 80 can be moved in the axial direction by the linear movement generated by the screw portion 94.

  The drive mechanism 90 is located on the cylinder bottom side of the air cylinder device 70. On the cylinder bottom side, there is also an electronic control circuit 100 that gives a control command to the drive mechanism 90. The electronic control circuit 100 has a microcomputer function as will be described in more detail later. The circuit 100 includes a power supply terminal 151 for connection to the battery 150, a connector 510 for setting control data suitable for each person of the prosthetic leg wearer, and a sensor comprising a magnet 14m and a proximity switch 14s. There is a sensor terminal 141 that receives a signal from 140 (that is, a sensor for detecting walking speed). Here, the power supply terminal 151 and the sensor terminal 141 are connected to the battery 150 or the sensor 140 through lead wires, respectively. On the other hand, the connector 510 has its insertion port facing an opening window 320w provided in the frame member 320.

  FIG. 3 shows a block diagram of a configuration in which the prosthetic leg 10 of the present invention and a personal computer 200 communicable with the electronic control circuit 100 in the prosthetic leg 10 are connected. The prosthetic leg 10 is the above-described femoral prosthesis, and includes a sensor 140, a battery 150, a drive mechanism 90, and a variable throttle valve 80 with the electronic control circuit 100 as a center. The electronic control circuit 100 has a microcomputer function, and includes a CPU 120 that calculates and processes data, and a memory 130 that stores data while exchanging data with the CPU 120. The electronic control circuit 100 controls the opening degree of the variable throttle valve 80 through the drive mechanism 90 based on the control data in the memory 130. The memory 130 of the electronic control circuit 100 also includes a portion for storing or accumulating usage frequency data for each of the multi-stage valve opening degrees.

  A personal computer 200 as an adjusting device is outside the artificial leg 10 and communicates with the electronic control circuit 100 on the artificial leg 10 side by wired or wireless communication. Thereby, processing for setting data in the memory 130 of the electronic control circuit 100 on the prosthetic leg 10 side or updating the set data is performed. The adjusting device 200 is a small microcomputer, and includes, for example, an input unit 210 that includes a plurality of keys and inputs data, a CPU 220 that calculates and processes data input to the input unit 210, and a CPU 220 And an output unit 230 that enables communication with the outside, a display unit 240 that displays data of the CPU 220, and a memory 260 that stores data. The figure shows an example of wired communication. The personal computer 200 as an adjusting device and the electronic control circuit 100 on the artificial leg 10 side are electrically connected through a cable 250 having a connector 270 (a connector suitable for the connector 510 on the artificial leg 10 side) attached to one end. Make a good connection. In wireless communication, there are communication circuits on the side of the artificial leg 10 and each input / output unit of the adjusting device 200, and wireless communication is possible through these communication circuits. Therefore, the cable 250 or the like in the case of wired is unnecessary, and the cable 250 does not interfere with walking training and data processing.

  In a prosthetic leg system including the prosthetic leg 10 and the adjusting device 200, at the beginning of walking training, setting data for valve opening in multiple stages (that is, walking) that will be suitable for the walking of the prosthetic leg wearer in the memory 130 on the prosthetic leg 10 side. Save and set the valve opening setting data for speed). This initial setting data is empirical data based on a dialogue between a prosthetic leg wearer and an expert. As the walking training progresses, the prosthetic leg wearer gets used to the prosthetic leg, and the appropriate setting data changes accordingly. Therefore, it is desirable to readjust or update (that is, adjust) existing setting data at an appropriate timing.

  In the present invention, in order to objectively grasp the timing of such adjustment, the use frequency data of each stage of the valve opening based on the actual walking of the prosthetic leg wearer is accumulated, and the accumulated data is used. Determine whether adjustment is necessary. Since the accumulated data is data based on actual walking, the primitive storage location is the memory 130 on the artificial leg 10 side. Then, the data stored in the memory 130 is processed, thereby obtaining an appropriate timing for adjustment. Accordingly, the data processing of the accumulated data can be performed by the electronic control circuit 100 on the prosthetic leg 10 side, or can be performed on the adjustment device 200 side outside the prosthetic leg 10. In order to reliably notify the necessity of adjustment to a prosthetic leg wearer, an expert, or the like, it is preferable to provide a notification means on the artificial leg 10 side and / or the adjustment device 200 side. As the notification means, for example, means for generating light by a light emitting element, sound by a buzzer, vibration by a vibrator, or the like is used.

  FIG. 4 shows an example of frequency information based on the actual walking of the prosthetic leg wearer wearing the prosthetic leg 10 set at the beginning. The horizontal axis is the walking speed (that is, the valve opening degree), and the vertical axis is the number of steps (that is, the usage frequency). This frequency information is information with a total number of steps of several thousand steps, and can be obtained in a relatively short time. In other words, it is information at a very early stage than the stage where the frequency distribution is displaced to the side where the walking speed is fast (for example, the stage where the total number of steps is tens of thousands of steps).

  In FIG. 4, a distribution curve a indicating the Mt. Fuji distribution is an actually acquired distribution, and a curve b along the distribution curve a is an approximate distribution thereof. Here, necessary data processing is performed using the approximate distribution b. When attention is paid to the approximate distribution b, the right side (the side where the walking speed is slow) gradually decreases from the peak portion M indicating the maximum number of steps. Appropriate data processing can be performed by applying fuzzification or the like when the slow walking speed reaches such a monotonous decrease. Such a time point is usually the stage before the total number of steps reaches several thousand. Even if the curve b itself indicating the approximate distribution is examined, it is not possible to grasp whether there is distortion (in other words, a phenomenon that should be determined that adjustment of setting data is necessary).

  On the other hand, when looking at a curve c indicating a first-order difference obtained by subtracting the first-order differential or first-order difference of the approximate distribution b, and a curve d indicating a second-order difference obtained by second-order differentiation or second-order difference of the approximate distribution b, A clear distortion can be found. For many prosthetic leg wearers, as a result of acquiring and examining curves c and d indicating such a first-order difference or second-order difference at the stage of walking training, when a distortion is found in these curves c and d, It was confirmed that the setting data for the prosthetic leg corresponded to the time point to be adjusted.

  Looking at the curves c and d, a sudden change is seen in the waveform of the distribution curve on the left side (the side where the walking speed is fast) from the peak portion M indicating the maximum number of steps, and a distorted one is found there. However, in the curve c indicating the first-order difference, such a distortion-like object is located above the zero line L indicating the step frequency of zero, so that it is difficult to grasp as distortion in data processing. On that point, the curve d indicating the second-order difference has a portion that crosses the zero line L, and data processing can be performed by paying attention to the portion. In this case, it is assumed that the strain is located at a location P where the zero line L crosses, and the height before and after the location P is grasped as the magnitude of the strain. When the magnitude Y of the distortion exceeds a predetermined threshold value, it is reasonable to determine that the setting data needs to be adjusted. Since the number of steps greatly varies depending on the walking speed, the threshold is determined in consideration of the distance X (distortion position) between the peak portion M indicating the maximum number of steps and the point P. Is good. That is, it is preferable that the threshold value be set larger near the peak portion M and set smaller as the distance from the peak portion M increases.

  Therefore, basically, it is possible to objectively determine whether or not the setting data needs to be adjusted by determining whether or not distortion greater than a predetermined threshold value has occurred. In actual data processing, as described above, it is related to the magnitude of the distortion rather than directly determining whether or not the distortion of the curve d indicating the second-order difference is not less than a predetermined magnitude. It is better to determine whether or not the indirect magnitude of the adjustment is equal to or greater than a reference value. In any case, the necessity of adjustment is very objective because it is determined by a comparative judgment whether or not the magnitude determined in relation to the distortion is equal to or greater than a reference value. If it is determined that the adjustment is necessary, a process for obtaining the walking speed set value and the valve opening can be performed according to the magnitude of the adjustment. Therefore, an appropriate adjustment can be performed at an appropriate timing.

  FIG. 5A shows respective curves before adjustment corresponding to FIG. 4, and FIG. 5B shows similar curves after adjustment. From the comparison of these two figures, it will be understood that the obvious distortion of the portion P seen before the adjustment is corrected after the adjustment. Note that since the frequency information is a relatively small number of steps with a total number of steps of several thousand steps, a change in distribution as seen in a step with several tens of thousands of steps or more (for example, the position of the peak portion M indicating the maximum number of steps) Is not seen).

  Next, processing or operation performed by the artificial leg 10 and / or the adjusting device 200 will be described based on the above-described concept. When adjusting the setting data of the walking speed set in the memory 130 of the artificial leg 10 (that is, the setting data of the valve opening with respect to the walking speed), the adjustment is generally performed by the adjusting device 200 outside the artificial leg 10. 6 and 7 show a flow of processing when the walking speed setting data is performed by the external adjustment device 200. FIG. 6 is a prosthetic leg flowchart on the artificial leg 10 side, and FIG. 7 is an adjustment apparatus flowchart on the adjustment device 200 side. Each is shown.

  As shown in the prosthetic leg flowchart of FIG. 6, the CPU 120 on the prosthetic leg 10 side determines whether or not there is communication with the adjustment device 200 (S <b> 1). When the determination result is “NO”, information from the sensor 140 is acquired (S2), and it is determined whether or not the user is walking based on the sensor information (S3). Next, a setting value of the walking speed corresponding to the sensor information is acquired from the memory 130 (S4), and the valve opening degree of the variable control valve 80 is controlled by the drive mechanism 90 based on the acquired setting value of the walking speed (S5). . Further, the step number information corresponding to the set value of the walking speed used for the control is acquired from the memory 130 (S6), the acquired step number information is added (+1), and the result is stored again in the same memory 130 (S7). On the other hand, when the presence / absence of communication with the adjustment device 200 is “YES” in step S1, step count information in the memory 130 is transmitted to the adjustment device 200 side in response to a request from the adjustment device 200 (S8). During the communication, it is determined whether or not walking speed setting data is received from the adjusting device 200 (S9). When receiving, the received walking speed setting data is stored in the memory 130 (S10). In response to storing the new setting data in this way, all the step count information in the memory 130 is deleted (S11), and the communication is terminated (S12).

  On the other hand, as shown in FIG. 7, the external adjustment device 200 can start communication with the prosthetic leg 10 by requesting the prosthetic leg 10 to communicate (S20). The CPU 220 of the adjustment device 200 determines whether or not communication has started (S21), and requests step count information from the prosthetic foot 10 in response to the start (S22). Then, it is determined whether or not the acquisition of the step information is completed (S23), and when the acquisition is confirmed, the frequency information is generated by sorting and normalizing the step information in descending order of the walking speed (walking speed setting value) ( S24). The frequency information in step S24 corresponds to the curves a and b in FIG. Next, a second-order difference is obtained for such frequency information (S25), and the magnitude and position of the distortion in the curve indicated by the second-order difference (curve d in FIG. 4) are calculated (S26, S27).

  The magnitude and position of these distortions are input when calculating the magnitude of adjustment by fuzzy inference. Therefore, the first fuzzy parameter is calculated from the distortion magnitude and the membership function, and the second fuzzy parameter is calculated from the distortion position and the membership function (S28, S29). Next, a fuzzy matrix is calculated based on the calculated first and second fuzzy parameters (S30). 8 to 10 show calculation examples in steps S28 to S30. FIG. 8 is an example of a membership function representing the degree to which an element belongs to a set. Here, five regions ZR, MS, MM, ML, and LG that are displaced by 0.25 from each other are defined, and the contribution ratio to each region is defined. For example, the strain magnitude 0.78843 belongs to the region ML with a degree of 0.8463 and the region LG with a degree of 0.1537, but does not belong to the other regions ZR, MS, and MM. The other strain position (peak distance) 0.375 belongs to the region MS and the region MM with a degree of 0.5, but does not belong to the remaining regions ZR, ML, and LG. FIG. 9 specifically shows the first and second fuzzy parameters determined by the membership function. FIG. 10 is a fuzzy matrix calculated from the first and second fuzzy parameters obtained as described above.

  The magnitude of the adjustment is calculated as a vector by multiplying the fuzzy matrix μij obtained in step S30 by the experience matrix Wij (S31). The experience matrix Wij is set in advance by an expert's rule of thumb. In order to set the empirical matrix Wij, a large number of experts are given various types of walking data samples including distortions whose sizes and positions are specified, and prosthetic leg setting value samples related to the walking data samples, Get an answer to the magnitude of the vector to be adjusted for the given. The experience matrix Wij is such that when the conditions (strain position and magnitude) given to each expert are input, the output is such that the answer from each expert is almost satisfied. Can be obtained.

  When the fuzzy matrix μij shown in FIG. 10 is multiplied by the experience matrix Wij shown in FIG. 11, the result shown in FIG. 12, that is, 10.88426 is obtained as the vector magnitude. And it is judged whether the magnitude | size of this vector is more than a reference value (S32). If the result of determination in step S32 is greater than or equal to the reference value, “adjustment required” is displayed indicating that adjustment is necessary (S33). Is displayed (S34). Here, the reference value is 10, for example. Therefore, the vector size 10.88426 is “adjustment required” because the vector size is 10 or more. As the magnitude of the reference value to be set, for example, a value can be selected such that the multistage valve opening setting data changes by one or more stages. Therefore, the reference value varies depending on the fineness of the valve opening setting data, and also varies depending on the adjustment method corresponding to the magnitude of the vector. The determination means for determining whether or not adjustment is necessary is the CPU 220 of the adjustment device 200, and the display unit 240 displays “adjustment required” or “adjustment unnecessary” according to a command from the CPU 220. Although the display by the display unit 240 is visual, in order to reliably notify those who are involved in the adjustment, in addition to the visual display, notification by voice or the like can be added.

  When the determination of “adjustment is required” is made, processing for adjusting the walking speed set value is performed according to the size of the vector to be adjusted (S35). The specific method of adjustment is not limited to a specific method, and there are several methods. The first method of setting the adjustment point on the extension line of the straight line connecting the point with the fastest walking speed and the next fastest point on the setting data graph that has already been set. A second method for setting a point, a third method for connecting with a fixed slope, a fourth method for setting at a position separated by the magnitude of the vector with the same slope as the average slope in the setting data graph, etc. Conceivable. Here, by performing the fourth method, as shown in FIG. 13, the point A located at the position where the walking speed before adjustment is moved by the horizontal axis direction 9 and the vertical axis direction 2 from the fastest point F is adjusted. Set to point. That is, by setting a new adjustment point A, the setting data of the valve opening is expanded by one step on the side where the walking speed is fast. When the adjustment in step S35 is completed, the adjustment device 200 transmits the adjusted walking speed setting value to the prosthetic leg 10 side (S36), and the adjustment work by the adjustment device 200 ends.

  In the embodiment described above, the necessity of adjustment is determined on the adjustment device 200 side, and the necessary adjustment is calculated on the adjustment device 200 side and transmitted to the artificial leg 10 side. However, while the adjustment of the walking speed setting value is performed on the adjustment device 200 side, the necessity of adjustment can be determined on the artificial leg 10 side. Furthermore, both the determination of necessity of adjustment and the adjustment of the walking speed set value can be automatically performed on the artificial leg 10 side.

  14 and 15 show another example of a prosthetic leg flowchart in the case where the necessity of adjustment is determined on the side of the artificial leg 10 and the adjustment of the walking speed setting value is performed on the adjustment apparatus 200 side. Although there is a difference in whether the process is performed by the artificial leg 10 or the adjustment device 20 side, many processes are the same as those described in FIGS. 6 and 7. Therefore, the common parts are not shown in the figure, and redundant description is omitted. Here, it should be noted that when the magnitude of the vector to be adjusted is greater than or equal to the reference value, an “adjustment required” flag that adjustment is necessary is set (S45), and the “adjustment required” flag set is set. It is to transmit to the adjustment apparatus 200 side (S47). The adjusting device 200 that has received the “need adjustment” flag set can display “need adjustment” on the display unit 240 and prompt the related parties to operate to adjust the walking speed setting value. It should be noted that each process for determining whether or not adjustment is necessary is started depending on whether or not the number of steps by the artificial leg 10 is equal to or greater than the reference (S40). It is based on the fact that the situation requiring adjustment exceeds the standard number of steps, for example, several thousand steps.

  16 and 17 show still another example of a prosthetic leg flowchart in the case where both the determination of necessity of adjustment and the adjustment of the walking speed set value are automatically performed on the prosthetic leg 10 side. Although the prosthetic leg 10 automatically adjusts the walking speed setting value, each processing itself is the same as the case described above. It should be noted that when the determination of whether or not walking (S62) is "No" / "NO", each process for determining the necessity of adjustment and adjusting the walking speed set value is performed. It is like that.

  The present invention can be applied to a prosthetic leg with various controls. For example, the present invention can be applied not only with the control of the swing phase but also with the control of the stance phase, and also with the control of both the swing phase and the stance phase. can do. Of course, as the fluid pressure control device, in addition to the piston type air cylinder device, a rotary type including a swing vane can be applied. For example, USP 2,530,286 or USP 2,568,053 is clarified as an example of using a piston type device for the stance phase control. As for devices using a rotary type device, for example, USP 5,704,945 (corresponding to JP-A-8-317944), USP 5,383,939 (corresponding to JP-A-5-212070), or USP 2,667,644 etc. make clear. For example, when the present invention is applied to yielding control as stance phase control of a prosthetic leg, control data to be set includes threshold values related to a load sensor for detecting (determining) the presence or absence of a load on the prosthetic leg, There are characteristics such as walking speed and valve opening.

It is a figure which shows an example of the artificial leg to which this invention is applied. FIG. 2 is a cross-sectional structure diagram showing a knee joint portion of the artificial leg in FIG. 1. It is a block diagram which shows the connection relation of the artificial leg by this invention, and an adjustment apparatus. It is a figure which shows the example of the frequency information based on the actual walk of the artificial leg wearer who mounted | worn the artificial leg set initially. It is a figure which shows each curve before the adjustment corresponding to FIG. It is a figure which shows each curve similar to FIG. 5A after adjustment. An example of the artificial leg flowchart by this invention is shown. An example of the adjustment apparatus flowchart by this invention is shown. An example of a membership function is shown. It is a figure which shows the 1st and 2nd fuzzy parameter concretely. It is a figure which shows the fuzzy matrix computed from the 1st and 2nd fuzzy parameter shown in FIG. It is a figure which shows an experience matrix. It is a figure which shows the magnitude | size of the vector which should be adjusted. The graph of the valve opening degree-walking speed setting value which shows the specific example of adjustment by this invention is shown. It is a 1st partial figure which shows another example of the artificial leg flowchart by this invention. FIG. 15 is a second partial view combined with FIG. 14. It is a 1st partial figure which shows another example of the artificial leg flowchart by this invention. FIG. 17 is a second partial view combined with FIG. 16.

Explanation of symbols

10 Prosthetic leg (femoral prosthesis)
310 First component member (knee member)
320 Second component (frame member)
70 Fluid pressure control device (air cylinder device)
80 Variable Control Valve 90 Drive Mechanism 100 Electronic Control Circuit 120 Prosthetic Side CPU
130 memory 200 adjusting device 220 CPU on adjusting device side
240 display section

Claims (14)

The first component member on the thigh side and the second component member on the crus side can be extended and / or bent at the knee portion, and the first component member is used to assist extension and / or bending of the knee. A fluid pressure control device is provided between the second component and the second component member, and the fluid pressure control device includes a variable control valve for restricting a fluid flow accompanying the extension and / or bending of the knee, and further includes the variable control valve. Electronic control that stores multi-stage valve opening setting data suitable for walking of a prosthetic leg wearer and outputs a valve opening control signal corresponding to walking based on the data to control the opening of the valve In an artificial leg provided with a drive mechanism that controls the opening of the variable control valve according to a control signal from the circuit and its electronic control circuit,
When determining whether or not the setting data of the valve opening should be adjusted, the following steps are provided, and a determination method for whether or not an artificial leg needs to be adjusted.
(A) A step of accumulating the use frequency data of each of the multi-stage valve openings based on the actual walking of the prosthetic leg wearer. (B) Differentiating the use frequency data of each of the multi-stage valve openings. And (C) paying attention to the waveform formed by the usage frequency information of each valve opening based on the differential value, and the waveform has a magnitude larger than a predetermined value. A step of determining that adjustment of the setting data of the valve opening is necessary when the condition that there is distortion is satisfied, and determining that the adjustment is unnecessary when the condition is not satisfied   Whether the magnitude of adjustment determined in relation to the magnitude of the distortion is greater than or equal to a reference value when determining whether or not the condition that there is a magnitude greater than the predetermined value in the step C is satisfied The determination method according to claim 1, wherein the determination is based on whether or not.   The differential value is any one of a value obtained by first-order differentiation, a value obtained by second-order differentiation, a value obtained by multi-order differentiation exceeding the second order, or a combination of a plurality of these values. Judgment method.   The magnitude of the waveform distortion formed by the usage frequency information of each valve opening based on the differential value is based on the magnitude of the difference between the maximum value and the minimum value near the inflection point of the waveform. Judgment method.   2. The determination method according to claim 1, wherein the predetermined value in the step C is set to be smaller for a strain further away from a point at which the use frequency information becomes the maximum value.   Prior to making the determination based on the step C, it is confirmed that the usage frequency data in the step A monotonously decreases from the maximum usage frequency portion to the usage frequency corresponding to the slowest walking speed. The determination method according to claim 1.   The determination method according to claim 1, wherein the electronic control circuit included in the artificial leg executes the A step, the B step, and the C step.   The electronic control circuit provided in the prosthetic leg executes the step A, is capable of communicating with the prosthetic leg, and sets the setting data of the valve opening over a plurality of stages suitable for the walking of the prosthetic leg wearer for the prosthetic leg. The determination method according to claim 1, wherein an adjuster having the function executes the B process and the C process. The first component member on the thigh side and the second component member on the crus side can be extended and / or bent at the knee portion, and the first component member is used to assist extension and / or bending of the knee. A fluid pressure control device is provided between the second component and the second component member, and the fluid pressure control device includes a variable control valve for restricting a fluid flow accompanying the extension and / or bending of the knee, and further includes the variable control valve. Electronic control that stores multi-stage valve opening setting data suitable for walking of a prosthetic leg wearer and outputs a valve opening control signal corresponding to walking based on the data to control the opening of the valve A prosthetic leg having a circuit and a drive mechanism for controlling the opening degree of the variable control valve in accordance with a control signal from the electronic control circuit, and whether or not the prosthetic leg should adjust the setting data of the valve opening degree To determine the power Prosthetic foot control circuit is characterized in that it comprises each of the following means.
(A1) Memory means for storing use frequency data of each of the multi-stage valve openings based on the actual walking of the prosthetic leg wearer. (B1) Use frequency data of each of the multi-stage valve openings. Differentiating means for differentiating and converting to usage frequency information of each valve opening based on the differential value (c1) Paying attention to the waveform formed by the usage frequency information of each valve opening based on the differential value, the waveform is larger than a predetermined value The determination means that it is necessary to adjust the setting data of the valve opening when the condition that there is a distortion is satisfied, and that the adjustment is not necessary when the condition is not satisfied   The artificial leg according to claim 9, wherein the determination unit determines whether or not an adjustment magnitude determined in relation to a distortion magnitude in the c <b> 1 is a reference value or more.   The prosthetic leg according to claim 9, further comprising notification means for notifying a determination result by the determination means. The first component member on the thigh side and the second component member on the crus side can be extended and / or bent at the knee portion, and the first component member is used to assist extension and / or bending of the knee. A fluid pressure control device is provided between the second component and the second component member, and the fluid pressure control device includes a variable control valve for restricting a fluid flow accompanying the extension and / or bending of the knee, and further includes the variable control valve. In order to control the opening of the valve, it memorizes the setting data of the valve opening over multiple stages suitable for the walking of the prosthetic leg wearer, and outputs the control signal of the valve opening according to the walking based on the data, , An electronic control circuit having a memory function for accumulating usage frequency data of each of the multistage valve openings based on the actual walking of the prosthetic leg wearer, and the variable according to a control signal from the electronic control circuit Control the opening of the control valve Artificial leg with a dynamic mechanism is the target,
The regulator is capable of communicating with the electronic control circuit of the prosthetic leg by wire or wirelessly, and has a function of setting setting data of the valve opening over a plurality of stages suitable for the walking of the prosthetic leg wearer with respect to the prosthetic leg. The regulator includes the following means for determining whether or not the setting data of the valve opening should be adjusted.
(B2) Differentiating means (c2) for differentiating the usage frequency data of each of the multi-stage valve openings based on the actual walking of the prosthetic leg wearer and converting it into usage frequency information of each valve opening based on a differential value Focusing on the waveform formed by the usage frequency information of each valve opening based on the differential value, adjustment of the setting data of the valve opening is necessary when the condition that the waveform has a distortion larger than a predetermined value is satisfied And means for determining that the adjustment is not necessary when the condition is not satisfied.   The adjuster according to claim 12, wherein the determination means determines whether or not an adjustment magnitude determined in relation to the distortion magnitude in the c2 is a reference value or more.   The adjuster according to claim 12, further comprising notification means for notifying a determination result by the determination means.

Images