Centroid display system

Abstract

To provide a centroid display system which can improve visibility of a movement of a centroid coordinate, when calculating and displaying, the centroid coordinate of the sole of a user, on the basis of a detection result of a load distribution sensor provided on a tread mill.SOLUTION: A centroid display system 10 comprises a display part 11 and a control part 12. The control part 12 inputs in time series, load distribution data, from a load distribution sensor provided on the tread mill and measuring a load applied to a top surface of a tread mill. The control part 12 inputs a movement speed of a user on the tread mill. The control part 12 displays a locus of the centroid coordinate, on the display part 11, in a state of deviating the centroid coordinate in an opposite direction of a movement direction on the basis of the movement speed, so that a display position of the centroid coordinate of the sole on one leg of the user indicated by the load distribution data, is at a relative position with respect to the same reference position regardless of a time, in one leg standing period.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a center of gravity display system. [Background technology]

[0002] Patent document 1 discloses a walking rehabilitation system comprising a treadmill, a floor reaction force sensor that measures the reaction force acting on the treadmill, a leg robot attached to the user's lower limbs, a distance measurement sensor that photographs the lower limbs to which the leg robot is attached, and a load estimation means that estimates the load on the soles of the user's feet without using a sensor attached to the user.

[0003] Here, the load estimation means estimates the sole load of each of the user's left and right lower limbs based on the measurement values ​​of the floor reaction force sensor and the measurement results of the distance measurement sensor from the resultant floor reaction force and its center of gravity position measured using the floor reaction force sensor and the distance measurement sensor, as well as the center of gravity position of the sole load of each of the user's left and right lower legs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6187208 Summary of the Invention [Problem to be solved by the invention]

[0005] The system described in Patent Document 1 is capable of calculating the position of the center of gravity of the load on each of the soles of the left and right feet of the user, but does not take into consideration at all the display of the trajectory.

[0006] The present inventor therefore considered a method of calculating the position of the center of gravity of the load on each of the soles of the user's left and right feet using a load distribution sensor provided on the treadmill and displaying the trajectory of the center of gravity.

[0007] However, since the position of the sole of the foot on the treadmill moves in the opposite direction to the moving direction as the user moves, when the center of gravity of the sole of the foot is displayed, the center of gravity also moves overall, making it difficult for the user and his / her caregiver to visually recognize the trajectory of the center of gravity of the sole of the foot. In particular, since the user usually strikes the ground with his / her heel, the moving direction of the treadmill (direction from the front to the rear) and the moving direction of the center of gravity of the sole of the foot (direction from the rear to the front of the sole) are opposite, making it difficult for the user and his / her caregiver to visually recognize the movement of the center of gravity. As a result, for example, the caregiver may give the user erroneous advice.

[0008] The present disclosure has been made to solve such problems, and its purpose is to provide a center of gravity display system that can improve the visibility of the movement of the center of gravity coordinate when calculating and displaying the center of gravity coordinate of the sole of a user's foot based on the detection results of a load distribution sensor installed on a treadmill. [Means for solving the problem]

[0009] A center of gravity display system according to one embodiment of the present disclosure includes a display unit and a control unit, wherein the control unit inputs load distribution data in a time series from a load distribution sensor disposed on a treadmill and measuring the load applied to the top surface of the treadmill, inputs the user's moving speed on the treadmill, and causes the display unit to display a trajectory of the center of gravity coordinates of the sole of the user's leg indicated by the load distribution data, with the center of gravity coordinates shifted in the opposite direction to the moving direction based on the moving speed so that the displayed position of the center of gravity coordinates of the sole of the user's leg indicated by the load distribution data is the same relative position to a reference position regardless of time during one stance phase for the leg.

[0010] In the above-mentioned center of gravity display system, when the center of gravity coordinate of the sole of the user's foot is calculated and displayed based on the detection results of a load distribution sensor arranged on the treadmill, the trajectory of the center of gravity coordinate is displayed on the display unit while the center of gravity coordinate is shifted in the opposite direction to the movement direction based on the above-mentioned movement speed, thereby improving the visibility of the movement of the center of gravity coordinate. Effect of the Invention

[0011] The present disclosure makes it possible to provide a center of gravity display system that can improve the visibility of the movement of the center of gravity coordinate when calculating and displaying the center of gravity coordinate of the sole of a user's foot based on the detection results of a load distribution sensor installed on a treadmill. [Brief description of the drawings]

[0012] [Figure 1] 1 is a block diagram showing an example of a configuration of a center of gravity display system according to an embodiment; [Diagram 2] 2 is a schematic side view showing one configuration example of a walking training device in which the center of gravity display system of FIG. 1 can be mounted. [Diagram 3] 3 is a schematic diagram showing an example of an image displayed on the walking training device of FIG. 2. [Figure 4] 3 is a flow chart for explaining an example of a center-of-gravity display process in the walking training apparatus of FIG. 2. [Diagram 5] 5 is a schematic diagram for explaining an example of a fixed region extraction process and a display coordinate correction process in the center of gravity display process of FIG. 4. [Figure 6] 5 is a schematic diagram showing an example of an image indicating the movement of the center of gravity coordinates of the sole displayed in the center of gravity display process of FIG. 4. [Figure 7] 13A and 13B are schematic diagrams showing display results in a center of gravity display process according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described below through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential as means for solving the problems.

[0014] (Embodiment) Hereinafter, an embodiment will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of the configuration of a center of gravity display system according to the present embodiment.

[0015] 1, a center of gravity display system 10 according to this embodiment can include a display unit 11 and a control unit 12. The display unit 11 can be a display panel such as a liquid crystal panel or an organic electroluminescence panel.

[0016] The control unit 12 inputs load distribution data in a time series from a load distribution sensor that is disposed on the treadmill and measures the load applied to the top surface of the treadmill. The load distribution sensor can be a surface pressure distribution sensor, a floor reaction force sensor, or the like. The control unit 12 also inputs the user's moving speed on the treadmill. The user's moving speed refers to the moving speed of the belt on the treadmill. The user's moving speed refers to the walking speed of the user when walking, and the running speed of the user when running.

[0017] The control unit 12 causes the display unit 11 to display the trajectory of the center of gravity coordinates in a state in which the center of gravity coordinates are shifted in a direction opposite to the moving direction based on the moving speed so that the display position of the center of gravity coordinates of the sole of one leg of the user indicated by the load distribution data is the same relative position to a reference position regardless of time during one stance phase of one leg. A specific shifting method will be described later with reference to Figs. 2 to 6. Here, the center of gravity coordinates of the sole of one leg of the user indicated by the load distribution data means the center of gravity coordinates of the load applied to the sole of that one leg.

[0018] The trajectory of the center of gravity coordinates can be updated and displayed successively at the timing of calculation of the center of gravity coordinates. For example, the control unit 12 can cause the display unit 11 to display the center of gravity coordinates calculated a predetermined number of times or calculated within a predetermined period from the latest calculation timing, and can also change the color so that the passage of time can be seen even between center of gravity coordinates displayed simultaneously. To make it easy for the user to understand, at least the current center of gravity coordinates can be displayed so as to be distinguished from past center of gravity coordinates.

[0019] In the center of gravity display system 10 configured as described above, when the center of gravity coordinate of the user's sole is calculated and displayed based on the detection results of a load distribution sensor arranged on the treadmill, the center of gravity coordinate is shifted in the opposite direction to the moving direction based on the above-mentioned moving speed, and the trajectory of the center of gravity coordinate is displayed on the display unit, thereby improving the visibility of the movement of the center of gravity coordinate.

[0020] Next, a specific example of the center of gravity display process by the control unit 12 will be described with reference to Fig. 2 to Fig. 6. In the following specific example, a treadmill is mounted on a walking training device 100 shown in Fig. 2, and the center of gravity display system 10 is mounted on the walking training device 100, but the present invention is not limited to this example.

[0021] First, an example of a walking training device 100 that can be equipped with a center-of-gravity display system will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is a schematic side view showing an example of a configuration of the walking training device 100 that can be equipped with the center-of-gravity display system 10. Fig. 3 is a schematic view showing an example of an image displayed on the walking training device 100.

[0022] The walking training device 100 shown in Fig. 2 is a device for a trainee (user) U, who is a hemiplegic patient suffering from paralysis in one leg, to perform walking training under the guidance of a training staff PT. The training staff PT may be a therapist (physiotherapist) or a doctor, and may also be called a training instructor, training assistant, or training assistant, since the training staff PT assists the trainee in training by providing guidance or assistance. As illustrated here, the training staff PT is a person.

[0023] The walking training device 100 includes a lower frame 101, an upper frame 102, a front frame 103, and a rear frame 104, which mainly form the overall shape of the device. The walking training device 100 can also include handrails 105 for the trainee U to hold on to as needed when walking. The handrails 105 can be provided on both sides of the area where the trainee U walks, for example, on the lower frame 101.

[0024] The walking training device 100 may also include an attachment 106 for attaching a training monitor 115 and a camera 117, which will be described later. In order to attach the training monitor 115 and the camera 117 so as to be located in front of the trainee U, the attachment 106 may be disposed on the front frame 103. The upper frame 102 also supports a front pulling part 111f near the front of the upper part of the trainee U's head, a harness pulling part 111w near the upper part of the head, and a rear pulling part 111b near the rear of the upper part of the head.

[0025] The walking training device 100 may also include a control panel 114 that houses an overall control unit configured with, for example, an MPU (Micro Processing Unit) that controls various motors and various sensors. That is, the overall control unit of the control panel 114 also controls the controllable parts of the walking training device 100. The control panel 114 may also include, as a part of the overall control unit, the center of gravity display system 10 of Fig. 1, that is, the display unit 11 and the control unit 12. In addition, the overall control unit of the control panel 114 may drive a belt drive unit 108 (described later) to adjust the rotation speed of the belt 107, for example, in accordance with the walking speed set by the training staff PT.

[0026] The control panel 114 can be supported, for example, by the lower frame 101. The overall control section of the control panel 114 can execute control of the entire apparatus by executing a control program read from the system memory.

[0027] The walking training device 100 also includes a treadmill that encourages the trainee U to walk. The treadmill can include an endless belt 107, i.e., a ring-shaped belt 107, and a belt drive unit 108. The belt drive unit 108 can include a motor that drives and rotates the belt 107 and a drive circuit for the motor. The trainee U who is undergoing walking training gets on the belt 107 and tries to walk in accordance with the movement of the belt 107. Note that the training staff PT can stand on the belt 107 behind the trainee U and walk together with the trainee U, for example, as shown in FIG. 2, but it is usually preferable for the training staff PT to be in a position that makes it easy to assist the trainee U, such as standing astride the belt 107.

[0028] The walking training device 100 also includes the above-mentioned load distribution sensor 107s. The load distribution sensor 107s can be disposed under the belt 107. The load distribution sensor 107s can be, for example, a resistance change detection type load detection sheet in which electrodes are arranged in a matrix.

[0029] The load distribution sensor 107s can be configured to detect the magnitude and distribution of the vertical load received by the soles of the trainee U, and detect the coordinates of the center of gravity of the load, that is, the coordinates of the COP (Center Of Pressure). The load distribution sensor 107s then transmits the detected load distribution data to the overall control unit of the control panel 114 via wired or wireless communication. The COP detection process itself can also be executed by the overall control unit upon receiving the magnitude and distribution of the vertical load detected by the load distribution sensor 107s.

[0030] The walking training device 100 may also include a fall prevention harness device as a safety device, the main components of which are an attachment 112, a harness wire 110w, and a harness tensioning unit 111w. The attachment 112 can be connected to one end of the harness wire 110w, which is a sling, and may also be called a hanger belt. The trainee U wears the attachment 112 so that the harness wire 110w is connected at the rear of the trainee. One end of the harness wire 110w is connected to the attachment 112, and the other end is connected to the harness tensioning unit 111w. The harness tensioning unit 111w may include a motor for tensioning the harness wire 110w and a drive circuit for the motor. The overall control unit of the control panel 114 controls the winding or unwinding of the harness wire 110w by sending a drive signal to the drive circuit of the harness tensioning unit 111w.

[0031] With this configuration, when the trainee U is about to fall, the fall prevention harness device winds up the harness wire 110w in accordance with an instruction from the overall control unit of the control panel 114 which detects the movement, and supports the upper body of the trainee U with the harness 112, preventing the trainee U from falling. The movement can be detected by a posture sensor (not shown) provided on the harness 112 for detecting the posture of the trainee U. This posture sensor is, for example, a combination of a gyro sensor and an acceleration sensor, and outputs the inclination angle of the abdomen to which the harness 112 is attached with respect to the direction of gravity.

[0032] The walking training device 100 may also include a walking assist device 109 that is attached to the affected leg, which is the paralyzed leg, of the trainee U. The walking assist device 109 is attached to the affected leg of the trainee U and assists the trainee U in walking by reducing the load of extension and flexion on the knee joint of the affected leg.

[0033] The walking assist device 109 may include, for example, a motor (not shown) that generates a driving force for assisting the extension and flexion of the knee joint, a control unit (not shown) that controls the motor, and a plurality of frames that support each part of the affected leg. Although these frames are not shown in detail, adjacent frames among these frames may be connected to be freely rotatable. The walking assist device 109 may also include various sensors that obtain various data related to the walking of the legs, and may transmit the obtained various data to the overall control unit of the control panel 114 by wired or wireless communication. The walking assist device 109 may also be configured to receive data related to the control of the motor as feedback, and control the motor based on the data by the control unit.

[0034] In addition, a front wire 110f and a rear wire 110b may be connected to some of the frames. The front wire 110f and the rear wire 110b are connected to a front pulling portion 111f and a rear pulling portion 111b, respectively, and can be wound up or unwound by the front pulling portion 111f and the rear pulling portion 111b. The front pulling portion 111f and the rear pulling portion 111b may include a motor and a drive circuit for pulling the front wire 110f and the rear wire 110b, respectively.

[0035] The overall control unit of the control panel 114 sends drive signals to the drive circuits of the front pulling unit 111f and the rear pulling unit 111b to control the winding or unwinding of the front wire 110f and the rear wire 110b, respectively. The overall control unit of the control panel 114 can assist the swinging motion of the affected leg by identifying the timing at which the affected leg switches from a stance state to a swing state based on at least one of the coordinates of the center of gravity of the sole of the trainee U based on the detection result of the load distribution sensor 107s and camera image data described below, and increasing or decreasing the pulling force of the front wire 110f and the rear wire 110b in synchronization with that timing.

[0036] In this way, the walking training device 100 can cancel the load of the walking assist device 109 so that the load is not a burden on the affected leg by the coordinated operation of the front pulling unit 111f and the rear pulling unit 111b, and can also assist the swinging motion of the affected leg according to the setting level. For example, the training staff PT, as an operator, sets a high assist level for the trainee U who has severe paralysis. When the assist level is set high, the front pulling unit 111f winds up the front wire 110f with a relatively large force in accordance with the swinging timing of the affected leg. When the training progresses and assistance is no longer necessary, the training staff PT sets the assist level to the minimum. When the assist level is set to the minimum, the front pulling unit 111f winds up the front wire 110f with a force that is sufficient to cancel the weight of the walking assist device 109 in accordance with the swinging timing of the affected leg.

[0037] The walking training device 100 may also include a training monitor 115 as an example of the display unit 11. The training monitor 115 is attached to the front frame 103, and may be, for example, a display panel such as a liquid crystal panel. The training monitor 115 is a display device that allows the trainee U to visually check his / her own walking state and the trajectory of the COP. The training monitor 115 may also display notifications such as advice and warnings given by the walking training device 100. Here, the advice may be advice that indicates what points to pay attention to when walking by feeding back the results of gait analysis.

[0038] The training monitor 115 can also be used by the training staff PT to visually check the walking state of the trainee U. Images and the like displayed on the training monitor 115 can be transmitted from the overall control unit of the control panel 114. The images for visually checking the walking state can include a real-time image taken by a camera 117 described later and a COP image 20a showing the trajectory of the COP, and can also include information showing the progress of the training and information for the above notification.

[0039] The walking training device 100 may also include a management monitor 116 as an example of the display unit 11. The management monitor 116 is attached to, for example, the housing of the control panel 114, and may be, for example, a display panel such as a liquid crystal panel. The management monitor 116 may also be provided with a touch panel on the display panel. The management monitor 116 is a display input device that is mainly used by the training staff PT to monitor and operate, but may also display the trajectory of the COP. The management monitor 116 displays various menu items related to training settings, various parameter values ​​during training, training results, and the like, and can accept settings of various menu items, various parameter values, and the like. Images and the like to be displayed on the management monitor 116 are transmitted from the overall control unit of the control panel 114, and an operation signal received by the touch panel of the management monitor 116 is transmitted to the overall control unit of the control panel 114, and control corresponding to the operation signal is performed by the overall control unit.

[0040] The walking training device 100 may also include an audio output unit (not shown). The notification contents displayed on the display units exemplified by the training monitor 115 and the management monitor 116 may be notified by audio output from this audio output unit, or may be notified by both image output on the display unit and audio output from the audio output unit.

[0041] The walking training device 100 also includes a camera 117. The camera 117 functions as an imaging unit for capturing an image of the entire body of the trainee U. The camera 117 is installed near the training monitor 115 so as to face the trainee U during training. Although an example in which the camera 117 is attached to the lower side of the attachment tool 106 is shown in FIG. 2, the attachment position of the camera 117 is not limited thereto.

[0042] The camera 117 takes still images and videos of the trainee U during training, and transmits the obtained image signals to the overall control unit of the control panel 114 via wired or wireless communication. The camera 117 can be a visible light or infrared camera. The camera 117 includes a lens and imaging element set that provides an angle of view that can capture the entire body of the trainee U when the trainee U is walking within an appropriate walking range. This angle of view is, for example, exemplified by the range between two dashed dotted lines in FIG. 2. The imaging element can be, for example, a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor, which converts an optical image formed on an imaging surface into an image signal.

[0043] The overall control unit receives an image signal from the camera 117 and generates image data indicated by the received image signal from the signal. Note that the camera 117 may also be configured to generate image data from the image signal and pass it to the overall control unit. The overall control unit controls the display of the image data on the training monitor 115. As a result, an image of the walking state of the trainee U, such as the camera image 20, is displayed in real time on the training monitor 115.

[0044] Although the image data displayed on the training monitor 115 is assumed to be camera image data obtained by photographing with the camera 117, it is not limited to camera image data and may be depth data, etc. The depth data may be a depth sensor that measures the distance to an object by shining infrared or other laser light on the object, or data obtained by photographing with a 3D camera or the like and mapping the depth of each position as an image. In addition, LiDAR data measured using LiDAR, which can be considered a type of depth sensor, may be input as image data.

[0045] In this way, in the walking training device 100, image data can be obtained by photographing or sensing the trainee U moving on the treadmill, and the image data can be displayed on the training monitor 115. In addition, the image data can also be displayed on the management monitor 116.

[0046] For convenience, in Fig. 3, images of some components, such as the training staff PT, the management monitor 116, wires, and harnesses, among images captured of the walking training device 100 in Fig. 2 are omitted. Also, in Fig. 3, an image showing a COP trajectory (hereinafter, COP image) 20a and a user skeleton image 30 are superimposed on a camera image 20, but such superimposition may not be performed. However, the function of displaying the COP image 20a is one of the features of this embodiment, and is assumed to be provided. At least one of the COP image 20a and the user skeleton image 30 may be displayed on the management monitor 116. The user skeleton image 30 and the COP image 20a will be described later.

[0047] In addition, the overall control unit of the control panel 114 can also perform gait analysis based on information including the obtained image data. Below, an example will be described in which the control unit 12 performs skeletal recognition processing for performing gait analysis and gait analysis based on the results of the processing.

[0048] The control unit 12 can recognize the position of the skeleton of the trainee U, who is the user, based on the image data, obtain user skeleton information indicating the position of the skeleton, generate a user skeleton image 30 from the user skeleton information, and display it on the training monitor 115. The position of each skeleton can be recognized as coordinates on the image data.

[0049] The method for recognizing the position of the skeleton from image data is not limited, and the position of the skeleton can also be recognized from multiple image data that are consecutive in time. A simpler recognition method is to add an identification marker to the position of the skeleton on a person or an accessory worn by the person and detect the marker, but it is possible to recognize the position of the skeleton without adding a marker. For example, the user skeleton information can be recognized as the output result of inputting image data into a learning model that has undergone machine learning such as deep learning.

[0050] The user skeletal information is information indicating the position of the trainee U's skeleton among information indicating the position of a person's skeleton indicated by a plurality of points (joint points, etc.) such as the right shoulder joint, shoulder part of the spine, left shoulder joint, right hip joint, base part of the spine, left hip joint, right knee joint, left knee joint, right ankle joint, left ankle joint, neck, and nose. Of course, the names of these joints, etc. are given only as examples. The user skeletal information may also include lines connecting adjacent points, or may include the above-mentioned lines instead of points.

[0051] Furthermore, when the image data includes data of the training staff PT, the control unit 12 may extract the skeleton of the trainee U separately from that of the training staff PT. The method of this distinction is not limited, but for example, the distinction can be made as follows. That is, the control unit 12 can distinguish the detected skeleton groups for each person by connecting adjacent skeletons among the detected skeleton groups that can be determined to be the skeletons of the same person according to predetermined skeleton information. Then, the control unit 12 identifies the skeleton information consisting of the skeleton group in the front as the user skeleton information that is the skeleton group of the trainee U as a result of this distinction, and generates a user skeleton image 30. For example, the skeleton information consisting of the skeleton group in the front can be determined by identifying the skeleton with the largest distance between the right shoulder and the left shoulder among the skeletons.

[0052] Alternatively, the control unit 12 can determine, among the skeletal information obtained by connecting the skeletons together, the one with the most complete skeletons as the skeleton of the trainee U and exclude the other skeletons (skeleton of the training staff PT), thereby identifying the user skeletal information and generating the user skeletal image 30. Note that, when the image data includes depth data, the control unit 12 can identify the skeletal information with a shallower depth as the user skeletal information.

[0053] However, without being limited to these examples, if the control unit 12 can distinguish and recognize the skeletal position of the trainee U from the skeletal positions of persons other than the trainee U based on the image data, it can extract the skeletal group of the trainee U, that is, extract it by distinguishing it from the skeletal groups of other persons such as the training staff PT.

[0054] The control unit 12 inputs the load distribution data from the load distribution sensor 107s in a time series, and displays the COP coordinate trajectory on the training monitor 115 in a state where the COP coordinate is shifted in the opposite direction to the moving direction based on the moving speed (treadmill speed) so that the display position of the COP coordinate of the sole of one leg of the user indicated by the load distribution data is the same relative position to the reference position regardless of time during one stance phase of one leg. The above-mentioned reference position can be the position where the load by the trainee U is first detected by the load distribution sensor 107s during the above-mentioned one stance phase. Since this position is the "heel" in normal walking, the following description will be given taking the heel as an example, but it is not limited to the heel.

[0055] Next, an example of such center of gravity display processing in the walking training device 100 will be described with reference to Fig. 4 to Fig. 6. Fig. 4 is a flow diagram for explaining an example of center of gravity display processing in the walking training device 100 of Fig. 2. Fig. 5 is a schematic diagram for explaining an example of fixed area clipping processing and display coordinate correction processing in the center of gravity display processing of Fig. 4. Fig. 6 is a schematic diagram showing an example of an image showing the movement of the COP coordinates of the sole of the foot displayed in the center of gravity display processing of Fig. 4.

[0056] First, the control unit 12 identifies user skeletal information indicating the skeleton of the trainee U based on the image data to be analyzed for gait, and performs gait analysis based on the identified user skeletal information (step S1). The gait analysis here does not need to be a precise analysis as long as it is possible to know whether the trainee is stepping, i.e., walking, and the ground contact state of the target foot. The target foot may be the foot wearing the walking assistance device 109, the opposite foot, or both feet.

[0057] Next, the control unit 12 determines whether or not the result of the gait analysis indicates a walking state (walking state) (step S2), and if it indicates that the state is not walking (NO), ends the processing.

[0058] If the answer is YES in step S2, i.e., if it indicates that the person is walking, the control unit 12 determines whether the results of the gait analysis indicate that the person is in a grounded state (step S3), and if it indicates that the person is not in a grounded state (if NO), the control unit 12 returns to step S1.

[0059] If the answer is YES in step S3, that is, if it indicates that the foot is in a grounded state, the control unit 12 determines whether the result of the gait analysis indicates that the foot has just landed (step S4). Note that the determination processes in steps S2 to S4 can be performed simultaneously.

[0060] If step S4 is YES, that is, if it indicates that the foot has just landed on the ground (YES), the control unit 12 calculates the heel starting point 52t1 from the ground contact portion 51t1 of the load distribution sensor 107s (step S5), as shown in the upper diagram of Fig. 5. The heel starting point 52t1 can be calculated by estimating the point where the foot first landed on the ground, and for example, the midpoint on the line with the smallest Y coordinate value in the load distribution immediately after the foot landed on the ground can be calculated as the heel coordinate. Here, the starting point 52t1 refers to the starting point at time t1.

[0061] Next, the control unit 12 cuts out a fixed area DAt1 to be displayed based on the coordinates of the origin 52t1 (step S6). Here, the fixed area DAt1 refers to a fixed area at time t1. The fixed area DAt1 can be determined and cut out as an area having a predetermined width in the X-axis direction centered on the X-coordinate of the origin 52t1 and another predetermined width in the Y-axis direction centered on the Y-coordinate of the origin 52t11, for example.

[0062] Next, the control unit 12 calculates the COP based on the load distribution (step S7), generates a COP image 20a showing the load distribution and the COP, and displays it on the training monitor 115 (step S8). Note that although the toes are drawn pointing up in Fig. 2, they can also be drawn pointing down.

[0063] On the other hand, if step S4 is NO, i.e., it indicates that the foot has not just landed (i.e., the foot is in the process of landing other than immediately after landing), the foot will be swept along by the treadmill (the foot moves depending on the treadmill speed), so the display area can be tracked according to the treadmill speed.

[0064] Therefore, in this case, first, the control unit 12 acquires the treadmill speed Vtr, which is the walking speed of the trainee U (step S9). Then, the control unit 12 calculates the amount of movement of the fixed area based on the acquired treadmill speed Vtr and the update period, and corrects the coordinates to be displayed (step S10). In the lower diagram of FIG. 5, the time one update period after time t1 is set to time t2, and the origin and fixed area at time t2 are expressed as origin 52t2 and fixed area DAt2, respectively. The amount of movement calculated in step S10 is the amount of movement V from fixed area DAt1 to fixed area DAt2, shown in the lower diagram of FIG. t2-t1 and the amount of movement V t2-t1 can indicate the amount of movement from the starting point 52t1 to the starting point 52t2. And the amount of movement V t2-t1 can be calculated by multiplying the treadmill speed by the update period.

[0065] After step S10, the control unit 12 executes the processes of steps S7 and S8, that is, the process of calculating the COP and the process of displaying the load distribution and the COP, and causes the training monitor 115 to display the COP image 20a generated at the corrected coordinates.

[0066] In this way, the control unit 12 changes the coordinates of the position that is the reference for the extraction range of the load distribution data as the reference position in the one stance phase (in this example, the coordinates of the heel) in the reverse direction based on the treadmill speed by the amount of movement V t2-t1 The control unit 12 then shifts the movement amount V by 100% to extract the load distribution data of the fixed area DAt2, thereby obtaining extracted distribution data. Next, the control unit 12 calculates the COP coordinates with respect to the reference position of the trainee U based on the extracted distribution data, and displays the trajectory of the calculated COP coordinates on the training monitor 115. In this way, the control unit 12 t2-t1 The fixed area to be drawn is slid and displayed for that amount of time.

[0067] Here, the COP coordinates can be calculated based on load distribution data obtained after a predetermined period of time has elapsed since the load applied by the trainee U was first detected during one of the stance phases. In this calculation method, the center of gravity during the stance phase is calculated using data obtained a short time after the foot touches the ground, which makes it possible to prevent the center of gravity from being unable to be calculated correctly due to the impact of the heel touching the ground.

[0068] In step S8, by displaying not only the COP trajectory but also the load distribution, the COP can be displayed as a pseudo outline of the user's sole (plantar) when the trainee U has landed entirely on the ground, and the outline of a portion of the sole can be displayed as a pseudo outline when only a portion of the sole has landed on the ground. However, the load distribution itself does not have to be displayed, that is, the load distribution does not have to be included in the COP image.

[0069] For example, as shown in FIG. 6, an enlarged view of the COP image 20a in FIG. 2 may be displayed together with an image AR of the sole of the foot contour prepared in advance corresponding to the size (total length) of the sole of the user's foot. The image AR and the image 61 may be aligned by, for example, aligning the positions of the heels. The COP image 20a also includes an arrow 62 indicating the direction of movement of the COP indicated by the COP trajectory. In this way, the control unit 12 can display an arrow indicating the direction of center of gravity movement indicated by the trajectory of the COP coordinates on the training monitor 115. However, the arrow 62 may not be included in the COP image 20a. Of course, the load distribution may also be included in the COP image 20a together with the image AR.

[0070] After the process of step S8, the process returns to step S1 and is repeated until step S2 becomes NO. The update frequency of the COP image 20a (corresponding to the update period), the update frequency of the user skeleton image 30, and the update frequency of the camera image 20 may be different from each other. For example, while the camera image 20 is displayed on the training monitor 115 in real time at the shooting rate, the COP image 20a and the user skeleton image 30 can be superimposed on the camera image 20 and displayed on the training monitor 115 each time information indicating the COP and the user skeleton is obtained.

[0071] In the above example, the cut-out range is determined after load detection, and the relative COP coordinate during the stance phase is calculated with respect to the reference position of the cut-out range (the COP coordinate of the ground contact part is calculated for each time), and the relative COP coordinate is displayed. That is, in the above example, the COP coordinate to be displayed is calculated using the coordinate in the cut-out range. However, the control unit 12 can simply shift the COP coordinate in the direction opposite to the moving direction based on the treadmill speed to set it as the COP display position, and the calculation of the COP display coordinate is not limited to the above example and can be performed by, for example, the following alternative method.

[0072] That is, in this alternative method, first, the control unit 12 calculates the COP coordinates of the sole of one leg based on the load distribution data. In this example, the COP coordinates can also be calculated based on the load distribution data obtained after a predetermined period has elapsed since the load applied by the trainee U was first detected in the one stance phase. Next, the control unit 12 shifts the calculated COP coordinates (converts the coordinates) by shifting the coordinates of the position serving as the reference of the center of gravity display target range of the load distribution data, which is the reference position in the one stance phase, in the opposite direction based on the treadmill speed. Then, the control unit 12 causes the training monitor 115 to display the trajectory of the COP coordinates after the shift (after the coordinate conversion). In this way, the cutout range (center of gravity display target range) may be determined after the calculation of the COP coordinates, as long as the calculated COP coordinates are converted into coordinates, or they may be processed simultaneously in parallel.

[0073] Furthermore, when the center of gravity movement direction indicated by the COP trajectory (the direction of the arrow 62 in FIG. 6) does not fall within a predetermined range, such as within a predetermined angle, the control unit 12 can also display advice on the movement method to the trainee U on the training monitor 115. Of course, the control unit 12 can also display on the training monitor 115 that there is no problem even when the center of gravity movement direction falls within the above-mentioned predetermined range. Here, the above-mentioned predetermined range can be, for example, a range set according to a target value of the mobility ability set for the trainee U.

[0074] In the above example, the load distribution data is assumed to be data inputted while the trainee U is wearing the walking assist device 109, which is an example of a legged robot, on one leg, and the control unit 12 causes the training monitor 115 to display the COP trajectory for at least the stance phase of the leg on which the walking assist device 109 is worn. However, it is also possible to display the COP trajectories for both legs, and in that case, it is preferable to display the COP trajectories for the right and left legs at different display positions.

[0075] The above describes an example of the configuration and processing of the walking training device 100 equipped with the center of gravity display system 10 of Fig. 1, and an application example thereof. As described above, in the walking training device 100, when the COP coordinates of the soles of the user's feet are calculated and displayed based on the detection results of the load distribution sensor 107s, the trajectory of the COP coordinates is displayed on the training monitor 115 in a state in which the COP coordinates are shifted in the opposite direction to the moving direction based on the treadmill speed. Therefore, the walking training device 100 can improve the visibility of the movement of the COP coordinates.

[0076] This effect will be further explained with reference to a comparative example. First, as Comparative Example A, an example will be given in which a sole sensor is used to draw and display the trajectory of COP coordinates in real time based on the load data from the sole sensor. In Comparative Example A, the use of the sole sensor increases the weight, and the trainee feels uncomfortable after removing the walking assistance device 109. In contrast, in this embodiment, the load distribution sensor 107s on the treadmill is used, so the trainee U does not feel such discomfort.

[0077] Next, a display result of the center of gravity display process according to Comparative Example B, which is different from Comparative Example A, will be described with reference to Fig. 7. Comparative Example B is an example of a process that does not perform correction processing of the display coordinates as in the present embodiment. Fig. 7 is a schematic diagram showing a display result of the center of gravity display process according to the comparative example.

[0078] In Comparative Example B, unlike Comparative Example A which uses a sole sensor, a load distribution sensor 107sc on the treadmill is used, so that the position on the treadmill in contact with the sole of the foot shifts as the foot moves based on the treadmill speed Vtr. Therefore, in Comparative Example B, the image showing the trajectory of the COP also shifts from image 72t1 to image 72t2, and the image of the contour of the sole of the foot also shifts from image 71t1 to image 71t2, making it difficult to visually recognize the movement of the COP. This is because the direction of the treadmill (the direction from the front to the rear as shown by the treadmill speed Vtr) and the direction of movement of the COP (the direction from the rear of the sole of the foot to the front) are opposite to each other.

[0079] In contrast, in this embodiment, a fixed area is cut out based on the part where the foot touches the ground, and the display area is tracked according to the treadmill speed, thereby improving the visibility of the foot center of gravity trajectory. That is, in this embodiment, for example, a fixed area is cut out based on the rear end (heel part) of the load coordinate where the foot touches the ground when the foot touches the ground, and the COP is displayed. Also, the cut out fixed area is tracked according to the speed of the running treadmill, improving the visibility of the center of gravity movement.

[0080] Furthermore, in Comparative Example B, the COP trajectory for a given period is displayed as being short, but in this embodiment, such a problem can also be solved.

[0081] <Alternative examples, etc.> In the above embodiment, the training staff PT is assumed to be one person, but the present invention may be applied to a case where there are multiple training staff or no training staff. Also, a non-human training assistant (mechanical, i.e., artificial training assistant) may be used instead of or in addition to the training staff PT. Examples of artificial training assistants include various types, such as humanoid robots, voice assistant programs for providing voice notifications, and display assistant programs for providing notifications by display.

[0082] When the training assistant is a program, it can be executablely incorporated in the walking training device 100, but it can also be executablely incorporated in a portable terminal such as a mobile phone (including those called smartphones) or a mobile PC, or an external server, which can communicate with the walking training device 100. The artificial training assistant can also be equipped with an artificial intelligence program (AI program).

[0083] In the above embodiment, the trainee U is assumed to be a hemiplegic patient suffering from paralysis in one of his legs, but the walking training device 100 may also be applied to a patient suffering from paralysis in both legs. In that case, the trainee performs training by wearing the walking assistance device 109 on both legs.

[0084] Furthermore, the configuration and shape of the walking training device 100 described in the above embodiment do not matter as long as the center of gravity display system 10 is mounted or connected. Furthermore, the center of gravity display system described in the embodiment can be configured with multiple devices by distributing functions. Similarly, the walking training device can be configured with multiple devices as a walking training system. Furthermore, the treadmill is not limited to being mounted on the walking training device, but may be mounted on a training support device such as a treadmill. In this case, the training support device can also be configured with multiple devices as a training support system. In any of the systems, when the system is configured with multiple devices, the devices may be connected to each other by wire or wirelessly.

[0085] As in the above embodiment, a configuration example in which the center of gravity display system 10 is incorporated in the walking training device 100 equipped with the camera 117 has been given, the present disclosure may also take the form of a walking training system equipped with the center of gravity display system and the above-mentioned treadmill body on which a load distribution sensor is installed. This walking training system may also be called a mobility training system, a mobility assistance system, or the like. In this walking training system, the control unit exemplified by the control unit 12 may be located anywhere, and may be located in the treadmill body, for example.

[0086] Furthermore, any one or more devices constituting the above-mentioned walking training device, training support device, or center of gravity display system or walking training system can have a hardware configuration including, for example, a processor, a memory, and a communication interface, etc. These devices are realized by the processor reading and executing a program stored in the memory.

[0087] Such a program includes instructions (or software code) that, when loaded into a computer, causes the computer to perform one or more functions described in the embodiments. The program may be stored in a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable medium or tangible storage medium includes random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technology, CD-ROM, digital versatile disc (DVD), Blu-ray® disk or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The program may be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, a transitory computer-readable medium or communication medium includes electrical, optical, acoustic, or other forms of propagated signals. [Explanation of symbols]

[0088] 10 Center of Gravity Display System 11 Display section 12 Control section 20 Camera Images 20a COP image 30 User skeleton images 61 COP trajectory images 62 Arrow 100 Walking training device 101 Lower Frame 102 Upper Frame 103 Front Frame 104 Rear Frame 105 Handrail 106 Mounting fixture 107 Belt 107s Load distribution sensor 108 Belt drive unit 109 Walking aids 110b Rear wire 110f Front Wire 110w harness wire 111b Rear tension part 111f Front tension section 111w Harness tension part 112 Orthotics 114 Control Panel 115 Training Monitor 116 Management Monitor 117 Camera AR Image of the sole of the foot PT Training Staff U Trainer

Claims

[Claim 1] A display unit and a control unit are provided. The control unit is inputting load distribution data in a time series from a load distribution sensor disposed on the treadmill and measuring the load acting on the upper surface of the treadmill; inputting a speed at which a user is moving on the treadmill; displaying a trajectory of the center of gravity coordinates on the display unit in a state in which the center of gravity coordinates are shifted in a direction opposite to a moving direction based on the moving speed so that a display position of the center of gravity coordinates of the sole of one leg of the user indicated by the load distribution data is a relative position relative to the same reference position regardless of time during one stance phase of the one leg; Center of gravity display system.

Images