JP2011200394A - Device and method for analyzing walking action, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To quantitatively analyze the walking action of a person mounted with a walking aid device.SOLUTION: First, a distance X in front and rear directions from the hip joint 212 of a mounting leg 210 to the toe 218 is calculated in first timing when the heel 219 of the mounting leg 210 mounted with the walking aid device separates the ground. Secondly, a distance Y in the front and rear directions from the hip joint 212 of the mounting leg 210 to the toe 218 is calculated in a second timing when the heel 219 of the mounting leg 210 is abutted onto the ground. Thus, the stride length A of the mounting leg 210 is obtained as A=2X+2Y through the use of the calculated distances X, Y.

Description

  The present invention relates to a technique for analyzing a walking action, and more particularly to a technique for analyzing a walking action of a person wearing a walking assistance device.

  Patent Document 1 discloses a wearable walking assist device. The walking assist device includes a plurality of mounting parts fixed to each part of the wearer's leg, a joint mechanism that connects the mounting parts so as to be swingable, and an actuator that drives the joint mechanism, By controlling the operation of the actuator over time, the movement of the wearer's leg during walking is assisted. This type of walking assist device is expected to significantly promote the recovery of the function of the patient, for example, in the rehabilitation of the patient whose physical ability has deteriorated.

JP 2010-35899 A

  In rehabilitation, the content is determined and adjusted according to the degree of functional recovery of the patient. Therefore, in order to appropriately advance patient rehabilitation, it is desirable to quantitatively grasp the degree of functional recovery. However, in the conventional rehabilitation, an assistant such as a physical therapist determines the degree of functional recovery of the patient based on the experience, and there is a problem that the determination lacks objectivity. In particular, in rehabilitation using a walking assist device, it is necessary to finely adjust the operation mode (operating parameters, etc.) of the walking assist device according to the degree of recovery of the function of the patient. It is required to quantitatively analyze the walking motion of the patient who has performed and objectively grasp the degree of functional recovery.

  In view of the above-described facts, the present invention provides a technique for quantitatively analyzing a walking motion of a person wearing a walking assistance device, and thereby, for example, in rehabilitation using a walking assistance device, the patient and its assistance. Enables a person to objectively grasp the degree of functional recovery.

  The present invention is embodied in an analyzer that analyzes a walking motion of a person wearing a walking assist device that is worn on one leg of the person. The analyzer includes a storage means for storing the length of the thigh and the lower leg of the wearing leg to which the walking assist device is attached, a thigh posture angle detecting means for detecting a posture angle of the thigh of the wearing leg, Crus posture angle detecting means for detecting a posture angle, heel contact detection means for detecting a first timing at which the heel of the mounting leg moves away from the ground, and a second timing at which the heel of the mounting leg abuts against the heel of the mounting leg, and detection Using the thigh and lower leg posture angles detected at the first timing and the lengths of the thighs and lower legs stored in the storage means, the distance in the front-rear direction from the hip joint to the toes is calculated. Using the first distance calculation means, the posture angles of the thighs and lower legs detected at the detected second timing, and the lengths of the thighs and lower legs stored in the storage means, Front to back A second distance calculating means for calculating the distance, using the calculated distance by the first distance calculating means and the second distance calculating means, and a step length calculating means for calculating a stride of mounting legs. Here, the stride length of the mounting leg is the distance in the front-rear direction (walking direction) from the position where the foot of the mounting leg is separated from the ground to the position where the foot of the mounting leg next contacts the ground. Means.

  This analyzer first calculates the distance in the front-rear direction from the hip joint of the mounting leg to the tip of the foot at the first timing when the heel of the mounting leg is separated from the ground. The first timing at which the heel of the mounting leg is separated from the ground is substantially the timing at which the toe of the mounting leg is positioned most backward with respect to the hip joint, and the other toe (the non-mounting leg) This is also the timing at which the toes are positioned in front of the hip joint. In addition, at this timing, both legs are extended to the same extent, and the distance in the front-rear direction from the hip joint of the attached leg to the toe and the distance in the front-rear direction from the hip joint of the non-attached leg to the toe are almost equal. It has become. Therefore, the distance calculated at the first timing described above is the distance in the front-rear direction from the hip joint of the attached leg to the foot tip, and is also the distance in the front-rear direction from the hip joint of the non-attached leg to the foot tip. It will be almost equal. Therefore, when the distance calculated at the first timing is doubled, the distance in the front-rear direction (ie, the first distance) from the toe of the attached leg located at the rear to the toe of the non-attached leg located at the front The step length for one step in the timing) can be obtained.

  Next, the analyzer calculates the distance in the front-rear direction from the hip joint of the mounting leg to the tip of the foot at the second timing when the heel of the mounting leg contacts the ground. The second timing at which the heel of the mounting leg abuts on the ground is substantially the timing at which the toes of the mounting legs are positioned most forward with respect to the hip joint, and the toes of the non-mounting leg are at the hip joint. On the other hand, it is also the timing at which it is located most backward. Furthermore, at this timing, both legs are almost extended, and the distance in the front-rear direction from the hip joint of the attached leg to the tip of the foot and the distance in the front-rear direction from the hip joint of the non-attached leg to the tip of the foot are substantially equal. ing. Therefore, the distance calculated at the second timing described above is the distance in the front-rear direction from the hip joint of the attached leg to the tip of the foot, and the distance in the front-rear direction from the hip joint of the non-attached leg to the tip of the foot. It will be almost equal. Therefore, when the distance calculated at the second timing is doubled, the distance in the front-rear direction (ie, the second distance) from the toe of the non-wearing leg located at the rear to the toe of the wearing leg located at the front The step length for one step in the timing) can be obtained.

  Then, the analyzer calculates the stride length of the wearing leg using the distance calculated at the first timing and the second timing. As is clear from the above description, the stride of the wearing leg can be obtained by adding twice the distance calculated at the second timing to twice the distance calculated at the first timing. Note that this calculation method is an example, and it is also effective to multiply a predetermined coefficient in accordance with, for example, the characteristics of the walking motion of the wearer, whereby the stride length of the wearing leg can be obtained more accurately. For example, in rehabilitation, the stride of a patient's affected leg (a leg that has deteriorated function) is an important guideline for determining the degree of functional recovery. Therefore, if the stride length of the attached leg can be obtained quantitatively, it is possible to objectively grasp the degree of functional recovery of the patient in rehabilitation using the walking assist device.

  An object of the present invention is to analyze a walking motion of a wearer by effectively using a sensor group included in a walking assist device. That is, the present invention proposes a method for analyzing the walking motion of the wearer using only information obtained from the limited sensor group in consideration of the sensor group already possessed by many walking assist devices. is there. Therefore, the above-described thigh posture angle detection means, crus posture angle detection means, and heel contact detection means use the output value of the sensor provided in the walking assist device, and the thigh posture angle, the lower leg posture angle, and It is preferable to detect the first timing and the second timing, respectively. However, the technology of the present invention has a certain effect even without using sensors existing in the walking assist device, and when the sensors required for the analysis are not present in the walking assist device, Necessary sensors may be separately attached to the walking assist device or the wearer.

  The analysis device described above includes a time measuring means for measuring the swing leg period from the detected first timing to the detected second timing, a time measured by the time measuring means, and a stride calculated by the stride calculating means. It is preferable to further include a speed calculation means for calculating the walking speed of the person wearing the walking assist device. According to this analyzer, the walking speed of the wearer can be grasped quantitatively. For example, in rehabilitation using a walking assist device, the degree of functional recovery of the patient can be grasped more objectively. .

  The analysis device described above uses the posture angles of the thighs and lower legs detected at the first timing detected and the lengths of the thighs and lower legs stored in the storage means, so that the height position of the hip joint of the mounting leg Hip height calculating means for calculating the height position calculated by the hip joint height calculating means, and posture angles of the thighs and lower legs detected during the swing leg period from the first timing to the second timing, It is preferable to further include a foot height calculating means for calculating the height position of the toes of the attached leg during the free leg period using the lengths of the thighs and lower legs stored in the storage means. According to this analysis device, it is possible to quantitatively grasp the toe transport (especially how the toes are raised) during the period when the attached leg is a free leg. For example, in rehabilitation using a walking assist device It becomes possible to more objectively grasp the degree of functional recovery of the patient.

The present invention is also embodied in an analysis method for analyzing a walking motion of a person wearing a walking assistance device that is worn on one leg of the person. This analysis method includes a memory step for storing the length of the thigh and the lower leg of the wearing leg, a thigh posture angle detecting step for detecting a posture angle of the thigh of the wearing leg, A crus posture angle detecting step of detecting a posture angle, a first timing at which the heel of the mounting leg is separated from the ground, and a heel contact detection step of detecting a second timing contact that comes into contact with the heel of the mounting leg; First, the front-rear direction distance from the hip joint of the wearing leg to the tip of the foot is calculated using the posture angles of the thigh and the lower leg detected at the first detected timing and the stored lengths of the thigh and the lower leg. Using the distance calculation step, the posture angle of the thigh and lower leg detected at the detected second timing, and the memorized length of the thigh and lower leg, the front-rear direction from the hip joint to the toe of the wearing leg Calculate the distance of the first Distances and calculating step, using the calculated distance by the first distance calculating step and the second distance calculating step includes a step length calculation step of calculating a stride of mounting legs.
According to this analysis method, it is possible to quantitatively grasp the stride length of the wearing leg, and for example, it is possible to objectively grasp the degree of functional recovery of the patient in rehabilitation using a walking assist device.

The present invention is also embodied in a program for analyzing a walking motion of a person wearing a walking assistance device that is worn on one leg of the person. This program stores, in the computer, a storage process for storing the length of the thigh and the lower leg of the mounting leg on which the walking assist device is mounted, a thigh posture angle detection process for detecting the thigh posture angle of the mounting leg, Crus posture angle detection processing for detecting the posture angle of the lower leg, first timing at which the heel of the mounting leg is separated from the ground, and second timing contact at which the heel of the mounting leg contacts the heel contact detection Using the processing, the posture angles of the thighs and lower legs detected at the first timing detected, and the memorized lengths of the thighs and lower legs, the distance in the front-rear direction from the hip joint of the wearing leg to the toes is calculated. Using the first distance calculation processing to be calculated, the posture angles of the thighs and lower legs detected at the detected second timing, and the memorized lengths of the thighs and lower legs, from the hip joint of the wearing leg to the toes Forward and backward A second distance calculating process of calculating away, using the calculated distance by the first distance calculating process and the second distance calculating process to execute the step length calculation process of calculating a stride of mounting legs.
According to this program, it is possible to quantitatively grasp the stride length of the wearing leg, and for example, it is possible to objectively grasp the degree of functional recovery of the patient in rehabilitation using a walking assist device.

  According to the present invention, it is possible to quantitatively analyze the walking motion of a patient wearing a walking assist device, for example, to quantitatively grasp the degree of functional recovery of a patient in rehabilitation using the walking assist device. it can. Thereby, it becomes possible to finely adjust the operation mode (operation parameters, etc.) of the walking assist device according to the degree of functional recovery of the patient, and the rehabilitation effect can be significantly enhanced.

The schematic diagram which shows the whole structure of a walking assistance system. The block diagram which shows the structure of a walking assistance system. The flowchart which shows the flow of the process which an analyzer performs. The figure which shows typically a wearer's walking posture in the timing (1st timing) in which the heel of a mounting leg leaves | separates from the ground. The figure which shows typically a wearer's walking posture in the free leg period (period from a 1st timing to a 2nd timing) in which a mounting leg is a free leg. The figure which shows typically a wearer's walking posture in the timing (2nd timing) at which the heel of a mounting leg contacts the ground. The figure which shows an example of the analysis result which an analyzer displays.

  The analysis device can be combined with a walking assistance device to construct a walking assistance system. In this case, it is preferable that the walking assist device has a sensor group that can detect the posture angles of the thigh and the lower leg of the wearing leg of the wearer. In this case, the walking assist device may include a posture angle sensor that detects a posture angle of the thigh and a posture angle sensor that detects a posture angle of the lower leg. Alternatively, by a combination of a posture angle sensor that detects the posture angle of the thigh and an angle sensor that detects the angle of the knee joint, or a combination of a posture angle sensor that detects the posture angle of the lower leg and the angle sensor that detects the angle of the knee joint Also, the posture angles of the thigh and the lower leg can be respectively detected. When the walking assist device has these sensor groups, the analysis device can detect the posture angles of the thighs and lower legs of the wearing legs using the sensor groups of the walking assist device.

  Furthermore, since the angle of the ankle joint when the toes are in contact with the foot uniquely corresponds to the posture angle of the lower leg, the posture angle sensor that detects the posture angle of the lower leg is used to detect the angle of the ankle joint. It can be replaced with a sensor. That is, by a combination of a posture angle sensor that detects the posture angle of the thigh and an angle sensor that detects the angle of the ankle joint, or a combination of an angle angle sensor that detects the angle of the knee joint and an angle sensor that detects the angle of the ankle joint Also, the posture angles of the thigh and the lower leg can be respectively detected. Therefore, even if the walking assist device has these sensor groups, the analysis device can detect the posture angles of the thighs and lower legs using the sensor groups of the walking assist device.

  In addition to the above, the walking assistance device preferably has a sensor that can detect whether or not the heel of the wearing leg of the wearer is in contact with the ground. Specifically, it is preferable to have a load sensor disposed below the heel of the wearer's mounting leg and switches disposed below the heel of the wearer's mounting leg. When the walking assist device has such a sensor, the analysis device uses the sensor group of the walking assist device, and the first timing at which the heel of the mounting leg separates from the ground or the heel of the mounting leg. The second timing of contact with the ground can be detected.

  As described above, it is preferable that the analysis device effectively uses the sensor group of the walking assist device. However, when the walking assist device does not have the sensor group described above, the necessary sensor group may be separately attached to the walking assist device or the wearer. That is, the analyzer according to the present invention does not necessarily use the sensor group of the walking assist device. The technology according to the present invention can be widely applied to various walking assistance devices regardless of the specific configuration of the walking assistance device.

  The analysis device can be combined with walking assist devices having various structures, and the range of use is not limited by the structure of the walking assist device. Preferably, however, the walking assist device includes a thigh unit disposed on the thigh of the mounting leg, a thigh unit disposed on the thigh of the mounting leg, a foot unit disposed on the toe of the mounting leg, It is good to have the knee joint unit which connects a unit and a leg unit so that rocking is possible, and an ankle joint unit which couples a leg unit and a foot unit so that rocking is possible. In this case, the posture angle sensor for detecting the posture angle of the thigh or the lower leg described above can detect the posture angle of the thigh or the lower leg of the wearing leg by detecting the posture angle of the thigh unit or the lower leg unit, respectively. . In addition, the angle sensor that detects the angle of the knee joint can detect the angle of the knee joint of the wearing leg by detecting the angle of the knee joint unit (that is, each of the thigh unit and the lower leg unit). . That is, it is not necessary to directly detect the posture and angle of the mounting leg.

  A walking assistance system 100 according to an embodiment will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating an overall configuration of the walking assist system 100, and FIG. 2 is a block diagram illustrating a functional configuration of the walking assist system 100. As shown in FIGS. 1 and 2, the walking assist system 100 is mainly configured by a walking assist device 10 and an analysis device 50. Although the walking assistance system 100 of a present Example is an example, it can be used for walking training of the patient 200 (henceforth a wearer) in a rehabilitation facility. 1 and 2, only one walking assist device 10 is illustrated, but the walking assist system 100 is configured by combining a plurality of walking assist devices 10 with one or a plurality of analysis devices 50. be able to.

  As shown in FIG. 1, the walking assist device 10 is attached to one leg 210 of the wearer 200 and assists the walking motion of the wearer 200 by applying an assist force to the wearing leg 210. Note that the walking assist device 10 is attached only to the leg 210 causing the wearer 200 to lose its function, and is not attached to the healthy leg 220. The walking assist device 10 includes a thigh unit 12 disposed on the thigh of the mounting leg 210, a lower leg unit 14 disposed on the lower leg of the mounting leg 210, and a foot unit 16 disposed on the foot of the mounting leg 210; It has a knee joint unit 13 that connects the thigh unit 12 and the crus unit 14 so as to be swingable, and an ankle joint unit 15 that connects the crus unit 14 and the toe unit 16 so that it can swing.

  As shown in FIG. 2, the walking assist device 10 includes a control unit 20, a motor 28, a posture angle sensor 22, a knee angle sensor 24, and a foot load sensor 26. The motor 28 is an actuator that drives the knee joint. That is, the motor 28 swings the crus unit 14 with respect to the thigh unit 12. Thereby, assist torque is applied to the knee joint of the mounting leg 210. The motor 28 is controlled by the control unit 20. The control unit 20 controls the motor 28 based on the sensor signals from the sensors 22, 24, and 26 described above. Thereby, the walking assistance apparatus 10 adjusts the assist torque to be output so as to follow the walking motion of the wearer 200.

  Here, the sensors 22, 24, and 26 of the walking assist device 10 will be described. The posture angle sensor 22 is a sensor for detecting the posture angle of the thigh of the mounting leg 210, and outputs a sensor signal corresponding to the posture angle (angle with respect to the horizontal direction or the vertical direction) of the mounting leg 210. is there. Although it is an example, the posture angle sensor 22 of the present embodiment is a gyro sensor fixed to the thigh unit 12. The knee angle sensor 24 is a sensor for detecting the angle of the knee joint of the mounting leg 210, and outputs a sensor signal corresponding to the angle of the knee joint of the mounting leg 210. Although an example, the knee angle sensor 24 of the present embodiment is an encoder that outputs a pulse signal in accordance with the rotation angle of the motor 28. The foot load sensor 26 is a sensor for detecting the contact pressure between the foot of the mounting leg 210 and the ground. Although it is an example, the foot load sensor 26 of the present embodiment is a plurality of load sensors provided on the foot unit 16 and is disposed below the foot of the mounting leg 210. Here, the plurality of load sensors include those arranged on the toe side and those arranged on the heel side, and it is also possible to detect the distribution of contact pressure between the toes of the mounting leg 210 and the ground. As will be described later, the sensor outputs of these sensors 22, 24, and 26 are used not only for control in the walking assist device 10 but also for processing in the analysis device 50.

  Next, the analyzer 50 will be described. As shown in FIG. 1, the analysis device 50 is configured using a general-purpose computer (electronic computer), and includes a computer main body 52, a monitor 54, and a user interface 56 such as a mouse and a keyboard. The analysis device 50 is connected to the walking assist device 10 via the cable 58, inputs the sensor outputs of the sensors 22, 24, and 26 provided in the walking assist device 10, and analyzes the walking motion of the wearer 200. Execute. The analysis device 50 and the walking assist device 10 may be connected so as to be able to communicate wirelessly without using the cable 58.

  As shown in FIG. 2, the analysis device 50 functionally includes a thigh posture angle detection unit 62, a crus posture angle detection unit 64, a heel contact detection unit 66, and a storage unit 68. Each component of the analysis apparatus 50 shown in FIG. 2 is configured by hardware and software (program) of the computer main body 52. The thigh posture angle detection unit 62 executes processing for detecting the thigh posture angle of the mounting leg 210. The thigh posture angle detector 62 of this embodiment receives the sensor output of the posture angle sensor 22 from the walking assist device 10 and detects the thigh posture angle of the mounting leg 210 based on the input sensor output. The lower leg posture angle detection unit 64 executes processing for detecting the lower leg posture angle of the mounting leg 210. The thigh posture angle detection unit 62 of this embodiment receives the sensor outputs of the posture angle sensor 22 and the knee angle sensor 24 from the walking assist device 10, and calculates the posture angle of the lower leg of the mounting leg 210 based on the input sensor output. To detect.

  The heel contact detection unit 66 performs processing for detecting whether or not the heel of the mounting leg 210 is in contact with the ground. In particular, the timing at which the heel of the mounting leg 210 is separated from the ground, and the mounting leg A process of detecting the timing at which the eyelid 210 comes into contact with the ground is executed. The heel contact detection unit 66 of the present embodiment receives the sensor output of the foot load sensor 26 from the walking assist device 10 and detects each timing described above based on the input sensor output. In this specification, the timing at which the heel of the mounting leg 210 is separated from the ground is simply referred to as a first timing, and the timing at which the heel of the mounting leg 210 is in contact with the ground may be simply referred to as a second timing. .

  The memory | storage part 68 memorize | stores the various information regarding the wearer 200, and can memorize | store especially the length of the thigh of the mounting leg 210, and the leg, respectively. The storage unit 68 can also store the first and last name of the wearer 200, other physical characteristics, a history of rehabilitation, and the like. Various kinds of information can be stored in the storage unit 68 using the user interface 56.

  The analysis device 50 further includes a distance calculation unit 70 and a stride calculation unit 72. The distance calculation unit 70 includes a thigh posture angle detected by the thigh posture angle detection unit 62, a crus posture angle detected by the crus posture angle detection unit 64, and the thigh and crus stored in the storage unit 68. Using the length, the distance in the front-rear direction from the hip joint of the mounting leg 210 to the tip of the foot can be calculated. The front-rear direction here is the front-rear direction of the wearer 200 and is equal to the walking direction of the wearer 200.

  Here, the specific calculation method executed by the distance calculation unit 70 is not limited to a specific method (that is, a specific mathematical formula). As an example, as shown in FIG. 4, when the posture angle of the thigh 212 is θ1, the length of the thigh 212 is L1, the posture angle of the lower leg 216 is θ2, and the length of the lower leg 216 is L2, the hip joint 212 of the mounting leg 210 is shown. The distance X in the front-rear direction from the foot to the toe 218 (exactly to the ankle position) can be calculated as X = L1 · sin θ1 + L2 · sin θ2. Here, the posture angle of the thigh 214 means an angle formed by the longitudinal direction of the thigh 214 with respect to the vertical direction, and the posture angle of the crus 216 forms the longitudinal direction of the crus 216 with respect to the vertical direction. Means a corner. That is, when the mounting leg 210 is upright, the posture angles of the thigh 214 and the lower leg 216 are substantially zero. As will be described in detail later, the distance calculation unit 70 performs the front-rear direction from the hip joint 212 to the toe 218 of the mounting leg 210 at each of the first timing and the second timing detected by the heel contact detection unit 66. The distances X and Y are calculated. Then, the stride calculation unit 72 calculates the stride A of the mounting leg 210 using the distances X and Y calculated for both timings.

  The analyzing device 50 further includes a swing time measuring unit 74 and a speed calculating unit 76. The swing leg timing unit 74 can count the time B between the first timing and the second timing detected by the heel contact detection unit 66. This measured time B is the length of the free leg period in which the mounting leg 210 is a free leg from when the hook of the mounting leg 210 is separated from the ground until the hook of the mounting leg 210 contacts the ground. Corresponds to (swing time). The speed calculation unit 76 calculates the walking speed C of the wearer 200 using the free leg time B measured by the free leg time measuring unit 74 and the stride A of the wearing leg 210 calculated by the above-described stride calculation unit 72. can do. The walking speed C is an example, but can be calculated as C = A / B.

  The analysis device 50 further includes a hip joint height calculation unit 78 and a toe height calculation unit 80. The hip joint height calculation unit 78 includes the thigh posture angle detected by the thigh posture angle detection unit 62, the lower leg posture angle detected by the lower leg posture angle detection unit 64, and the thigh and the thigh stored in the storage unit 68. The height Zref from the ground of the hip joint of the mounting leg 210 is calculated using the length of the lower leg. The calculation of the height Zref is executed during a period in which the toes of the mounting legs 210 are in contact with the ground, that is, a standing period from the second timing to the first timing.

  Here, the specific calculation method executed by the hip joint height calculation unit 78 is not limited to a specific method (that is, a specific mathematical expression). As an example, as shown in FIG. 4, when the posture angle of the thigh 214 is θ1, the length of the thigh 214 is L1, the posture angle of the lower leg 216 is θ2, and the length of the lower leg 216 is L2, the hip joint 212 of the mounting leg 210 is shown. The height Zref from the ground can be calculated as Zref = L1 · cos θ1 + L2 · cos θ2. It should be noted that the height Zref calculated by this mathematical formula is precisely the height from the ankle of the mounting leg 210 to the hip joint 212, so that a correction value may be added as necessary. In addition, in the calculation of the toe height Dt described below, this error is canceled out, so it is not always necessary to add a correction value.

  The toe height calculation unit 80 is detected by the hip joint height Zref calculated by the hip joint height calculation unit 78, the thigh posture angle detected by the thigh posture angle detection unit 62, and the crus posture angle detection unit 64. Using the posture angle of the lower leg and the length of the thigh and the lower leg stored in the storage unit 68, the height Dt of the foot of the mounting leg 210 from the ground can be calculated. The calculation of the height Dt is executed in a period in which the toes of the mounting legs 210 are separated from the ground, that is, in the free leg period from the first timing to the second timing.

  Here, the specific calculation method executed by the toe height calculation unit 80 is not limited to a specific method (that is, a specific mathematical formula). As an example, as shown in FIG. 5, the posture angle of the thigh 214 is θt, the length of the thigh 214 is L1, the posture angle of the crus 216 is θt, and the length of the crus 216 is L2. In this case, since the height Zt from the toe 218 of the mounting leg 210 to the hip joint 212 can be calculated as Zt = L1 · cos θt + L2 · cos θt, the height Dt of the mounting leg 210 from the ground 218 is , Dt = Zref−Zt. It should be noted that the height of the hip joint 212 from the ground fluctuates up and down with the walking motion and does not exactly match the height Zref calculated in advance. However, this fluctuation range is relatively small, and even if such an error occurs, it has been confirmed that a significant result can be obtained in the subsequent analysis processing.

  The analyzer 50 further includes a display processing unit 82. The display processing unit 82 executes a process for displaying the calculated indicators A, B, C, and D on the monitor 54. As will be described in detail later, as shown in FIG. 7, the display processing unit 82 displays the calculated indicators A, B, C, and D together with their target values and past values using a graph or a design. be able to.

  FIG. 3 is a flowchart showing a flow of processing executed by the analysis apparatus 50. The analysis device 50 executes the analysis process shown in FIG. 3 according to a program stored in advance. The analysis process by the analysis device 50 is executed while the wearer 200 is walking, and the walking motion of the wearer 200 is analyzed in real time. However, the analysis device 50 can also perform an analysis process on the basis of data collected in advance. Hereinafter, the processing executed by the analysis apparatus 50 will be described in the order in which the processing is executed along the flowchart shown in FIG.

  First, the heel contact detection unit 66 executes processing for detecting the timing at which the heel of the mounting leg 210 is separated from the ground, that is, the first timing (step S10). When the first timing is detected (YES in step S10), first, the swing leg timing unit 74 starts timing (step S12). Subsequently, the distance calculation unit 70 calculates the distance in the front-rear direction from the hip joint of the mounting leg 210 to the toe (step S14). That is, the distance calculation unit 70 detects the posture angle of the thigh detected at the first timing, the posture angle of the lower leg detected at the first timing, and the length of the thigh and the lower leg stored in the storage unit 68. Is used to calculate the distance in the front-rear direction from the hip joint of the mounting leg 210 to the tip of the foot. Hereinafter, the distance calculated in step S14 may be simply expressed as a first distance.

  FIG. 4 schematically shows the walking posture of the wearer 200 at the first timing. As shown in FIG. 4, the first timing at which the heel 219 of the mounting leg 210 is separated from the ground is the timing at which the toe 218 of the mounting leg 210 is positioned most backward with respect to the hip joint 212. In addition, the first timing is also a timing at which the foot tip 228 of the non-wearing leg 220 is positioned most forward with respect to the hip joint 222. Further, at this second timing, both the legs 210 and 220 extend to the same extent, and the distance X in the front-rear direction from the hip joint 212 of the mounting leg 210 to the toe 218 and the hip joint 222 of the non-mounting leg 220 The distance X ′ in the front-rear direction to the foot tip 228 is substantially equal. Therefore, when the first distance X calculated in step S14 is doubled, the front-rear direction from the foot tip 218 of the mounting leg 210 positioned rearward to the foot tip 228 of the non-mounting leg 220 positioned frontward is determined. The distance X + X ′ can be obtained almost accurately. This distance X + X ′ corresponds to the step length for one step at the first timing. As described above, the first distance X can be calculated as X = L1 · sin θ1 + L2 · sin θ2.

  Next, the hip joint height calculator 78 calculates the height Zref of the hip joint 212 of the mounting leg 210 at the first timing (step S16). That is, the hip joint height calculation unit 78 stores the posture angle θ1 of the thigh 214 detected at the first timing, the posture angle θ2 of the lower leg 216 detected at the first timing, and the storage unit 68. Using the lengths L1 and L2 of the thigh 214 and the lower leg 216, the height Zref from the ground of the hip joint 212 of the mounting leg 210 is calculated. As described above, the height Zref of the mounting leg 210 from the ground of the hip joint 212 can be calculated as Zref = L1 · cos θ1 + L2 · cos θ2 (see FIG. 4).

  Here, the processing from step S12 to step S16 described above is executed substantially simultaneously at the first timing, and the order is not limited to the order described above.

  Thereafter, the mounting leg 210 becomes a free leg, and its foot 218 moves in the air. During this time (until YES in step S18), the foot tip height calculation unit 80 repeatedly calculates the height of the foot tip 218 of the mounting leg 210 from the ground at a predetermined cycle (step S20). As described above, the height Dt of the toe 218 of the mounting leg 210 from the ground can be calculated as Dt = L1 · cos θ1 + L2 · cos θ2−Zt (see FIG. 5). Through this step S20, the height Dt of the toe 218 of the wearing clothes is repeatedly calculated over the period in which the wearing legs 210 are free legs. In addition, the toe height calculating unit 80 specifies the maximum value from the repeatedly calculated height Dt, and specifies the maximum height D of the toe 218 of the mounting leg 210.

  Thereafter, as shown in FIG. 6, when the heel 219 of the mounting leg 210 comes into contact with the ground, the timing (second timing) is detected by the heel contact detection unit 66 (YES in step S18). When the second timing is detected, the swing timing unit 74 ends the timing and determines the swing leg time B of the mounting leg 210 (step S22).

  Subsequently, the distance calculation unit 70 calculates the distance Y in the front-rear direction from the hip joint 212 of the mounting leg 210 to the toe 218 (step S24). That is, the distance calculation unit 70 includes the posture angle θ3 of the thigh 214 detected at the second timing, the posture angle θ4 of the lower leg 216 detected at the second timing, and the thigh 214 stored in the storage unit 68. The distance Y in the front-rear direction from the hip joint 212 of the mounting leg 210 to the toe 218 is calculated using the lengths L1 and L2 of the lower leg 216. Hereinafter, this distance Y may be simply expressed as the second distance Y. Although the second distance Y is an example, it can be calculated as Y = L1 · sin θ3 + L2 · sin θ4.

  As shown in FIG. 6, the second timing at which the heel 219 of the mounting leg 210 abuts the ground is the timing at which the toe 218 of the mounting leg 210 is positioned most forward with respect to the hip joint 212. In addition, the second timing is also a timing at which the foot tip 228 of the non-wearing leg 220 is positioned most rearward with respect to the hip joint 222. Further, at this second timing, both legs 210 and 220 extend to the same extent, and the distance Y in the front-rear direction from the hip joint 212 of the mounting leg 210 to the toe 218 and the hip joint 222 of the non-mounting leg 220 The distance Y ′ in the front-rear direction to the foot tip 228 is substantially equal. Accordingly, when the second distance Y calculated in step S24 is doubled, the front-rear direction from the toe 228 of the non-wearing leg 220 located at the rear to the toe 218 of the wearing leg 210 located at the front is determined. The distance Y + Y ′ can be obtained almost accurately. This distance Y + Y ′ corresponds to the step length for one step at the second timing.

  Subsequently, the stride calculation unit 72 calculates the stride A of the mounting leg 210 using the first distance X and the second distance Y calculated by the distance calculation unit 70 (step S26 in FIG. 3). As shown in FIG. 6, the stride A of the mounting leg 210 corresponds to the sum of the stride X + X ′ for one step at the first timing and the stride Y + Y ′ for one step at the second timing, and its value is A = 2X + 2Y. As described above, the analysis device 50 according to the present embodiment quantitatively measures the stride A of the mounting leg 210 by detecting only the timing of grounding and non-grounding of the mounting leg 210 and the posture of the mounting leg 210. Can do.

  Subsequently, the speed calculation unit 76 calculates the walking speed C of the wearer 200 by using the stride A calculated by the stride calculation unit 72 and the free leg time B timed by the free leg time measuring unit 74 (see FIG. 3 step S28). As described above, the walking speed C can be calculated as C = A / B.

  As a result of the above processing, each index such as the stride A of the mounting leg 210, the free leg time B of the mounting leg 210, the walking speed C of the wearer 200, and the maximum height D of the toe 218 of the mounting leg 210 is obtained as an analysis result. The value is calculated. Each calculated index value is displayed on the monitor 54 of the analyzer 50 by the display processing unit 82 (step S30 in FIG. 3). Analyzing apparatus 50 repeatedly executes the processing flow shown in FIG. 3 until receiving an instruction to end the analyzing process (YES in step S32). Thereby, while the wearer 200 is walking, the calculation and display of each of the index values A, B, C, and D described above are repeated in real time (simultaneously) for each step of the wearing leg 210.

  FIG. 7 shows a display example of the analysis result on the monitor 54. In the display example shown in FIG. 7, the name of the wearer 200, information indicating the rehabilitation period, and the like are displayed on the upper portion 90. In the middle part 92, for each index value A, B, C, D, the average value of the values calculated in the current analysis is displayed together with the target value set for the wearer 200 and the average value in the previous analysis. Is displayed. In the lower portion 94, the index values A, B, C and D calculated for each step of the mounting leg 210 are displayed while being updated in real time. With such a display, an assistant such as a physical therapist can quantitatively grasp the degree of functional recovery of the wearer 200 and appropriately adjust the operation mode (operation parameters, etc.) of the walking assist device 10. Is possible. As a result, the rehabilitation of the wearer 200 is appropriately advanced, and the functional recovery thereof is significantly promoted.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  For example, the walking assist device 10 can be suitably used not only for patients who perform rehabilitation but also for workers engaged in heavy labor. The technique of the present invention can be similarly applied to the walking assist device 10 used by such workers. Even in this case, it is possible to appropriately adjust the operation mode of the walking assist device 10 according to the worker by quantitatively analyzing the walking motion of the worker wearing the walking assist device 10. Furthermore, the obtained analysis results can be used effectively for analysis of the working environment, and the process design can be improved by reviewing the work procedure and the working environment.

  In addition, the analysis device 50 described in the embodiment can follow the walking motion of the wearer 100 and perform the analysis processing at the same time (in real time). It can also be performed after the operation is completed. In this case, only the process of accumulating the detection values by the sensors 22, 24, 26 may be executed during the walking motion of the wearer 100. It should be noted that the analysis device 50 is not necessarily used at the stage of accumulating the detection values by the sensors 22, 24, and 26, and a data storage device for accumulating the detection values may be provided in the walking assist device 10. Conceivable. According to this method, it is not necessary to connect the analysis device 50 and the walking assist device 10 during the walking motion of the wearer 100, and the wearer 100 can easily walk.

  Although the analyzer 50 of the present embodiment is configured using a general-purpose electronic computer, it is not always necessary to use a general-purpose electronic computer. For example, the processing executed by the analysis device 50 can be executed by the processing unit 20 included in the walking assistance device 10. That is, the walking assist device 10 having the function of the analysis device 50 can be realized. In this case, the analysis result analyzed in the walking assist device 10 may be stored in the analysis device 50, or may be transmitted to an external computer or the like by wireless or wired and displayed in real time by the computer. .

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10: walking assist device 20: control unit 22: posture angle sensor 24: knee angle sensor 26: foot load sensor 28: motor 50: analysis device 54: monitor 62: thigh posture angle detection unit 64: lower leg posture angle detection unit 66 : Heel contact detection unit 68: storage unit 70: distance calculation unit 72: stride length calculation unit 74: swing leg time unit 76: speed calculation unit 78: hip joint height calculation unit 80: toe height calculation unit 82: display processing unit 100: Walking assistance system 200: Wearer (patient)
210: Wearing leg 220: Non-wearing leg A: Step length B: Swing leg time C: Walking speed D: Maximum height of the toe

Claims (6)

An analysis device for analyzing a walking motion of a person wearing a walking assistance device attached to one leg of a person,
Storage means for storing the length of the thigh and the lower leg of the wearing leg to which the walking assist device is attached;
Thigh posture angle detecting means for detecting the posture angle of the thigh of the mounting leg;
Lower leg posture angle detecting means for detecting the lower leg leg angle of the wearing leg;
Heel contact detection means for detecting a first timing at which the heel of the mounting leg separates from the ground and a second timing at which the heel of the mounting leg contacts the heel of the mounting leg,
Using the posture angles of the thighs and crus detected at the detected first timing and the lengths of the thighs and crus stored in the storage means, the distance in the front-rear direction from the hip joint of the wearing leg to the toes is calculated. A first distance calculating means for calculating;
Using the posture angles of the thighs and lower legs detected at the detected second timing and the lengths of the thighs and lower legs stored in the storage means, the distance in the front-rear direction from the hip joint of the wearing leg to the toes is calculated. A second distance calculating means for calculating;
Stride calculation means for calculating the stride of the wearing leg using the distance calculated by the first distance calculation means and the second distance calculation means;
An analyzer comprising: Timing means for timing the swing leg period from the detected first timing to the detected second timing;
Speed calculating means for calculating the walking speed of the person wearing the walking assistance device using the time measured by the time measuring means and the stride calculated by the stride calculating means,
The analyzer according to claim 1, further comprising: The hip joint height for calculating the height position of the hip joint of the wearing leg using the posture angle of the thigh and the lower leg detected at the detected first timing and the length of the thigh and the lower leg stored in the storage means Calculation means;
Using the height position calculated by the height calculation means, the posture angles of the thighs and lower legs detected during the free leg period, and the lengths of the thighs and lower legs stored in the storage means, Toe height calculating means for calculating the height position of the toes of the attached legs;
The analyzer according to claim 1, further comprising:   At least one of the thigh posture angle detection unit, the crus posture angle detection unit, and the heel contact detection unit detects the above-described index using an output value of a sensor provided in the walking assist device. The analyzer according to any one of claims 1 to 3. An analysis method for analyzing a walking motion of a person wearing a walking assist device attached to one leg of a person,
A storage step for storing the length of the thigh and the lower leg of the wearing leg to which the walking assist device is attached;
A thigh posture angle detection step of detecting a posture angle of the thigh of the wearing leg;
A lower leg posture angle detecting step for detecting a lower leg leg angle of the wearing leg;
A heel contact detection step for detecting a first timing at which the heel of the mounting leg is separated from the ground and a second timing contact at which the heel of the mounting leg contacts the heel of the mounting leg;
First, the front-rear direction distance from the hip joint of the wearing leg to the tip of the foot is calculated using the posture angles of the thigh and the lower leg detected at the first detected timing and the stored lengths of the thigh and the lower leg. 1 distance calculation process,
First, a distance in the front-rear direction from the hip joint of the wearing leg to the tip of the foot is calculated using the posture angle of the thigh and the lower leg detected at the detected second timing and the stored length of the thigh and the lower leg. 2-distance calculation process;
Using the distances calculated by the first distance calculation step and the second distance calculation step, the step length calculation step of calculating the step length of the wearing leg;
An analysis method comprising: A program for analyzing the walking motion of a person wearing a walking assistance device that is worn on a person's leg,
A storage process for storing the length of the thigh and the lower leg of the wearing leg to which the walking assist device is attached;
Thigh posture angle detection processing for detecting the posture angle of the thigh of the wearing leg;
Lower leg posture angle detection processing for detecting the lower leg posture angle of the wearing leg;
A heel contact detection process for detecting a first timing at which the heel of the mounting leg is separated from the ground, and a second timing contact at which the heel of the mounting leg contacts the heel of the mounting leg;
First, the front-rear direction distance from the hip joint of the wearing leg to the tip of the foot is calculated using the posture angles of the thigh and the lower leg detected at the first detected timing and the stored lengths of the thigh and the lower leg. 1 distance calculation processing,
First, a distance in the front-rear direction from the hip joint of the wearing leg to the tip of the foot is calculated using the posture angle of the thigh and the lower leg detected at the detected second timing and the stored length of the thigh and the lower leg. 2-distance calculation processing,
A stride calculation process for calculating a stride of the wearing leg using the distance calculated by the first distance calculation process and the second distance calculation process;
A program that executes

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