Patent Publication Number: US-11376471-B2

Title: Balance training apparatus and control program of balance training apparatus

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese patent application No. 2019-047890, filed on Mar. 15, 2019, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND 
     The present disclosure relates to a balance training apparatus and a control program of a balance training apparatus. 
     Training apparatuses for enabling patients who have disabilities in their legs to perform rehabilitation training have become more and more widespread. For example, a training apparatus in which a trainee who performs training stands on a footplate, the centroid position of the trainee is observed, and the footplate is moved by driving means in order to encourage the trainee to step forward and to prevent the trainee from falling has been known (sec, for example, Japanese Unexamined Patent Application Publication No. 2015-100477). 
     SUMMARY 
     In a configuration in which the footplate is moved by a small amount with respect to the training apparatus, the trainee basically maintains an upright state with respect to the floor surface. In this configuration, since there is hardly any environmental change, it is difficult for the trainee to maintain his/her motivation for the training. On the other hand, if a game-like feature is, for example, given to the trial of the training, the trainee will try to perform the trial of the training with a higher motivation as the trainee has a greater physical experience in conjunction with a game. It has been revealed that a configuration in which a balance training apparatus is provided with a moving cart and the whole balance training apparatus on which the trainee rides is moved is effective for rehabilitation training. 
     In the aforementioned balance training apparatus, however, it is required to adjust, for example, the difficulty level of the training such as the acceleration, the moving speed and the like of the cart in accordance with the degree of recovery of the trainee. In particular, since the degree of recovery of the trainee and the progress speed of the training vary depending on the age, physical strength and the like of the trainee, the difficulty level of the training needs to be finely set for each trainee. 
     The present disclosure has been made in order to solve the aforementioned problem, and provides a balance training apparatus and the like in which it is possible to adjust the difficulty level depending on the trainee who Has a disability in his/her balance functions when he/she performs rehabilitation training. 
     A balance training apparatus according to a first aspect of the present disclosure includes: a moving cart capable of moving on a moving surface by driving a driving unit; a movement controller configured to drive the driving unit and to move the moving cart in accordance with a predetermined swing pattern; a posture detection sensor configured to detect that disturbance of a state of a trainee who is standing on the moving cart has become outside of a predetermined range; and a difficulty level setting unit configured to instruct the movement controller to change the swing pattern and change the difficulty level of the training that moves the moving cart based on results of detecting the state of the trainee regarding which a notification is sent from the posture detection sensor. 
     As described above, by detecting the magnitude of the disturbance of the posture of the trainee by the training and changing the difficulty level of the training, training suitable for the trainee can be provided for the trainee. 
     The aforementioned posture detection sensor may include at least one of a handrail sensor provided in a handrail attached to the moving cart, a pressure sensor that is provided between the handrail and a strut that supports the handrail, a biological sensor that is attached to a part of the body of the trainee and detects biological information of the trainee, and a camera that is attached to the moving cart and captures an image of the posture of the trainee. 
     Further, the aforementioned difficulty level setting unit may reduce the difficulty level when a duration period of a state during which disturbance of the state of the trainee regarding which a notification is sent front the posture detection sensor has become outside of the predetermined range has exceeded a first specified value. 
     Further, the aforementioned difficulty level setting unit may instruct the movement controller to stop the training when the duration period of a state during which disturbance of the state of the trainee regarding which a notification is sent from the posture detection sensor has become outside of the predetermined range has exceeded a third specified value that is larger than the first specified value. 
     Further, the aforementioned difficulty level setting unit may reduce the difficulty level when an integrated value of a time period of a state during which disturbance of the state of the trainee regarding which a notification is sent from the posture detection sensor has become outside of the predetermined range has exceeded a predetermined rate in a determination threshold period having a predetermined length. 
     Further, the aforementioned difficulty level setting unit may increase the difficulty level when a duration period of a state during which the disturbance of the state of the trainee regarding which a notification is sent from the posture detection sensor is within the predetermined range has become equal to or larger than a difficulty level increase determination period set based on a second specified value. 
     Further, a control program of a balance control apparatus according to a second aspect is a control program of a balance training apparatus in which a trainee standing on u moving cart that moves on a moving surface performs balance training, the control program causing a computer to execute the following steps of: a movement control step for driving a driving unit that moves the moving cart to move the moving cart in accordance with a predetermined swing pattern; a posture detection step for detecting that disturbance of the state of the trainee has become outside of a predetermined range; and a difficulty level setting step for changing the swing pattern and changing the difficulty level of the training that moves the moving cart based on results of detecting the state of the trainee regarding which a notification is sent in the posture detection step. According to the balance training apparatus controlled by the aforementioned control program, by detecting the magnitude of the disturbance of the posture of the trainee by the training and changing the difficulty level of the training, it is possible to provide training suitable for the trainee for the trainee. 
     According to the present disclosure, it is possible to provide training at a difficulty level in accordance with the physical ability of the trainee who has a disability in his/her balance functions when he/she performs rehabilitation training. 
     The above and other objects, features and advantages of the present disclosure will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic perspective view of a training apparatus according to a first embodiment; 
         FIG. 2  is a diagram showing a system configuration of the training apparatus according to the first embodiment; 
         FIG. 3  is a schematic view for describing a function of the training apparatus according to the first embodiment; 
         FIG. 4  is a diagram for describing difficulty levels of training of the training apparatus according to the first embodiment; 
         FIG. 5  is a flowchart for describing an operation of the training apparatus according to the first embodiment; 
         FIG. 6  is a timing chart for describing a change in the difficulty level of the training in the training apparatus according to the first embodiment; 
         FIG. 7  is a liming chart for describing a change in a difficulty level of training in a training apparatus according to a second embodiment; 
         FIG. 8  is a flowchart for describing an operation of a training apparatus according to a third embodiment; 
         FIG. 9  is a flowchart for describing an operation of difficulty level up processing of the training apparatus according to the third embodiment; 
         FIG. 10  is a flowchart for describing an operation of a training apparatus according to a fourth embodiment; 
         FIG. 11  is a schematic view for describing a function of a training apparatus according to a fifth embodiment; 
         FIG. 12  is a schematic view for describing a function of a training apparatus according to a sixth embodiment; 
         FIG. 13  is a schematic view for describing a function of a training apparatus according to a seventh embodiment; and 
         FIG. 14  is a schematic view for describing a function of a training apparatus according to an eighth embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, the present disclosure will be explained with reference to embodiments of the present disclosure. However, the disclosure set forth in the claims is not limited to the following embodiments. Further, not ail the structures explained in the embodiments may be necessary as means for solving the problem. Further, in the following description, components that are common in a plurality of embodiments are explained in the description of one embodiment, and the descriptions thereof will be omitted in other embodiments. 
     First Embodiment 
       FIG. 1  is a schematic perspective view of a training apparatus  100 , which is one example of a balance training apparatus according to a first embodiment. The training apparatus  100  is an apparatus for enabling a disabled person having a disability such as hemiplegia to learn a centroid movement that is necessary for walking or enabling a patient who has a disability in his/her ankle joint to recover an ankle joint function. When, for example, a trainee  900  who desires to recover the ankle joint function continues to ride the training apparatus  100  while balancing himself/herself, the training apparatus  100  is able to give the ankle joint of the trainee  900  a load that can be expected to achieve rehabilitation effects. 
     The training apparatus  100  includes a moving cart  110  that can move on a moving surface, which is a floor surface or the like of a rehabilitation facility, in the front/back direction, and a frame  160  that is installed in the moving cart  110  and prevents the trainee  900  who rides the moving cart  110  from falling off. The moving cart  110  mainly includes driving wheels  121 , casters  122 , a riding plate  130 , load sensors  140 , and a control box  150 . 
     The driving wheels  121  are provided as two front wheels with respect to the traveling direction. The driving wheels  121 , which are rotationally driven by a motor (not shown) provided as a driving unit, move the moving cart  110  forward or backward. The casters  122 , which are trailing wheels, are provided as two rear wheels with respect to the traveling direction. The riding plate  130  is a riding part where the trainee  900  rides and puts his/her feet. The riding plate  130  is a flat plate made of, for example, polycarbonate resin having a relatively high rigidity that can withstand riding of the trainee  900 . The riding plate  130  is supported on the upper surface of the moving cart  110  via the load sensors  140  arranged at four corners of the riding plate  130 . 
     The load sensors  140 . which are, for example, load cells, function as detection units configured to detect loads received from the feet of the trainee  900  who is standing on the moving cart  110 . The control box  150  accommodates an operation processing unit and a memory that will be described later. 
     The frame  160  includes an opening door  161  and a handrail  162 . The opening door  161  is opened when the trainee  900  rides the riding plate  130  and forms a passage where the trainee  900  passes. When the trial of the training is performed, the opening door  161  is closed and locked. The handrail  162  is provided so as to surround the trainee  900  so that the trainee  900  is able to hold the handrail  162  when he/she is about to lose his/her balance or when he/she feels unsafe. The frame  160  supports a display panel  170 . The display panel  170 , which is, for example, a display unit such as a liquid crystal panel, is provided in a position where the trainee  900  can easily see it during the trial of the training. 
       FIG. 2  is a diagram showing a system configuration of the training apparatus  100 . An operation processing unit  200 , which is. for example, an MPU, executes a control program loaded from a memory  240 , thereby executing control of the entire apparatus. A driving unit (e.g., a driving wheel unit  210 ) includes a driving circuit and a motor for driving the driving wheel(c)  121 . Further, the driving wheel unit  210  includes a rotary encoder configured to detect the rotation amount of the driving wheels  121 . 
     An operation reception unit  220  accepts an input operation from the trainee  900  or an operator and transmits an operation signal to the operation processing unit  200 . The trainee  900  or the operator operates an operation button provided in the apparatus, a touch panel overlapped with the display panel  170 , an attached remote control or the like, thereby turning on/off the power supply, giving an instruction for starting the trial of the training, inputting numerical values regarding setting, or selecting a menu item. 
     A display controller  230  generates, for example, an instruction regarding the posture to be sent to the trainee  900 , a graphic image of a task game or the like in accordance with a display signal from the operation processing unit  200 , and displays the generated message or image on the display panel  170 . The memory  240 , which is a non-volatile storage medium, may be, for example, a solid state drive. The memory  240  stores a control program etc. for controlling the training apparatus  100 . The memory  240  further stores parameter values, functions. lookup tables and the like such as a plurality of swing patterns to be used for control. The memory  240  stores, in particular, a task game  241 , which is a program for giving a task in a form of a game so as to allow the trainee  900  to enjoy performing the trial of the training, and a swing pattern  242  that defines how to operate the moving cart  110 . The load sensor  140  detects a load applied from the foot of the trainee  900  via the riding plate  130  and transmits the detection signal to the operation processing unit  200 . A posture detection sensor  250  detects that disturbance of the state of the trainee  900  has become outside of a predetermined range. The posture detection sensor  250  detects disturbance of the posture of the trainee  900  or disturbance of the state of the trainee  900  such as the heart rate in a state in which the posture detection sensor  250  contacts the trainee  900  or does not contact the trainee  900 . 
     The operation processing unit  200 , which is a calculation unit, also serves as a function execution unit configured to execute various operations and control of individual elements in accordance with a request from the control program, A load calculation unit  201  acquires the detection signals from the four load sensors  140  and calculates the center of gravity of the loads of the respective feet of the trainee  900  on the riding surface. More specifically, since the respective positions of the four load sensors  140  are known, the centroid position is calculated from the distribution of the loads in the vertical direction detected by the respective load sensors  140 , and this position is set as a center of gravity of the loads. 
     A range setting unit  202  sets a range of stability, which is a range of the center of gravity of the load estimated that the trainee  900  can maintain his/her upright state on the riding surface. A movement controller  203  drives the driving wheel unit  210  based on the movement amount of the center of gravity of the load and moves the moving cart  110  in accordance with a predetermined swing pattern. Further, the movement controller  203  generates a driving signal to be transmitted to the driving wheel unit  210 , and controls the movement of the moving cart  110  via the driving wheel unit  210 . 
     A difficulty level setting unit  204  instructs the movement controller  203  to change the swing pattern to change the difficulty level of the training that moves the moving cart  110  based on the results of detecting the state of the trainee  900  regarding which a notification is sent from the posture detection sensor  250 . In the first embodiment, the posture detection sensor  250  transmits, when the posture of the trainee  900  shows disturbance whose magnitude is equal to or larger than a predetermined range, the results of the detection to the difficulty level setting unit  204 . Then the difficulty level setting unit  204  instructs the movement controller  203  to decrease the difficulty level of the training when the disturbance of the state of the trainee  900  regarding which a notification is sent from the posture detection sensor  250  has continued for a predetermined first threshold or more. 
     Note that the training apparatus  100  according to the first embodiment also performs active load training which actively moves the moving cart  110  to maintain the posture of the trainee  900 , in addition to the training of moving the moving cart  110  in accordance with the movement of the center of gravity of the load of the trainee  900 . That is, in the active load training of the training apparatus  100  according to the first embodiment, the functions of the load sensor  140 , the load calculation unit  201 , and the range setting unit  202  are not actively used. On the other hand, in the active load training of the training apparatus  100  according to the first embodiment, the movement controller  203  gives a driving instruction to the driving wheel unit  210  in accordance with the swing pattern  242  stored in the memory  240  to move the moving cart  110 . 
     Now, a method of adjusting the difficulty level, which is one of the features of the training apparatus  100  according to the first embodiment, and the configuration of the training apparatus  100  will be described in further detail.  FIG. 3  shows a schematic view for describing a function of the training apparatus according to the first embodiment. The configuration shown in  FIG. 3  is the one that selectively shows configurations that are necessary for adjustment of the difficulty level that will be described below, and the training apparatus  100  according to the first embodiment includes, for example, other configurations shown in  FIG. 1 . Further, in  FIG. 3 , descriptions of the configurations the same as those described with reference to  FIG. 1  will be omitted. 
     As shown in  FIG. 3 , the training apparatus  100  according to the first embodiment is provided with a handrail switch  310  in the handrail  162  attached to a strut (e.g., the frame  160 ) installed in the moving cart  110 . This handrail switch  310  is one of sensors that can be used as the posture detection sensor  250 . Further, in the example shown in  FIG. 1 , the form in which the power supply button that instructs a power supply displayed on the display panel  170  to be turned on/off is attached to the frame  160  as a training switch  320  has been shown. In this way, by providing the training switch  320  in the frame  160 , it becomes possible for the operator to easily start or stop operating the training apparatus  100 . 
     In the training apparatus  100  according to the first embodiment, the difficulty level of the training is adjusted in accordance with the physical strength and the degree of the recovery of the trainee  900 . Therefore, in the training apparatus  100  according to the first embodiment, a plurality of swing patterns of the moving cart  110  are set as the training provided for the trainee  900 . The swing pattern  242  stored in the memory  240  includes a plurality of swing patterns. This swing pattern  242  includes a plurality of swing patterns whose difficulty levels are different from one another.  FIG. 4  shows one example of the swing pattern  242 .  FIG. 4  is a diagram for describing difficulty levels of the training of the training apparatus according to the first embodiment. The upper diagram in  FIG. 4  shows a graph for describing a change in the speed of the moving cart  110  by the swing pattern and parameters for changing the speed. Further, the lower diagram in  FIG. 4  shows a table in which parameters of the swing patterns are listed for each difficulty level. 
     In the example shown in  FIG. 4 , the swing pattern according to the first embodiment is indicated by a speed change curve graph expressed by a speed function F using three parameters, that is, a stop period Tl, a swing period T 2 , and a speed strength parameter A. More specifically, in the example shown in  FIG. 4 , in the swing pattern according to the first embodiment, when the target speed is denoted by v, a traveling direction parameter that indicates the traveling direction of the moving cart  110  is denoted by S, the time elapsed after the start of the training is denoted by t, the stop period is denoted by T 1 , the swing period is denoted by T 2 , and the speed strength parameter is denoted by A, the target speed v can be expressed by Expression (1). It is assumed that the moving cart  110  moves in the forward direction when the traveling direction parameter S in Expression (1) is 1. whereas the training apparatus  100  moves in the backward direction when the traveling direction parameter S is −1.
 
 v=S×F ( t,A,T 1 ,T 2)   (1)
 
     Further, in the example shown in the lower diagram of  FIG. 4 , the swing pattern according to the first embodiment defines the difficulty levels from 1 to 5, in which the difficulty level  5  indicates the highest difficulty level and the difficulty level  1  is the lowest difficulty level. The swing pattern whose difficulty level is the highest moves the moving cart  110  at a high speed within a short period of time. On the other hand, the swing pattern whose difficulty level is low moves the moving cart  110  at a low speed while taking a long period of time. 
     Next, an operation of the training apparatus  100  according to the first embodiment will be explained.  FIG. 5  shows a flowchart for describing an operation of the training apparatus according to the first embodiment. While a case in which the lowest difficulty level is set to 1 and the highest difficulty level is set to 5 is shown in the example shown in  FIG. 5 , the way in which the difficulty level is increased or decreased may be changed as appropriate in accordance with the way of setting the difficulty level. 
     As shown in  FIG. 5 , in the training apparatus  100  according to the first embodiment, first, the training switch is turned on, whereby the training is started (Step S 1 ). When the training is started, the difficulty level setting unit  204  sets a difficulty level counter that stores the value that specifies the swing pattern to be 5 (Step S 2 ), Then a handrail ON counter defined in a register or the like in the difficulty level setting unit  204  is set to 0 and a difficulty level down flag is set to 0 (Step S 3 ). After that, the difficulty level setting unit  204  refers to the value of the difficulty level counter and determines the swing pattern (Step S 4 ). Then the training apparatus  100  controls the moving cart  110  in accordance with the swing pattern selected in Step S 4  (Step S 5 ). 
     Next, in the training apparatus  100  according to the first embodiment, when the handrail switch  310  indicates the OFF state, the difficulty level setting unit  204  sets the handrail ON counter to 0 (YES in Step S 6 ). Further, in the training apparatus  100 , when the handrail switch  310  indicates the ON state (NO in Step S 6 ), the difficulty level setting unit  204  increases the value of the handrail ON counter by one (Step S 10 ). After that, the difficulty level setting unit  204  determines whether the handrail ON counter exceeds a predetermined first specified value (Step S 1 ). When it is determined in Step S 11  that the handrail ON counter is equal to or smaller than the first specified value, the difficulty level setting unit  204  performs the determination in Step S 8 . On the other hand, when it is determined in Step S 11  that the handrail ON counter is larger than the first specified value, after the difficulty level setting unit  204  rewrites the difficulty level down flag to 1, it makes a determination of Step S 8  (Step S 12 ). Step S 8  is determination regarding whether the training switch has been set to the OFF state. When it is determined in Step S 12  that the training switch has been set to the OFF state, the training apparatus  100  stops the operation (Step S 9 ). On the other hand, when it is determined in Step S 8  that the training switch is in the ON state, the movement controller  203  of the training apparatus  100  determines whether the swing pattern is being executed at the current timing (Step S 21 ). 
     When the movement controller  203  has determined in Step S 21  that the swing pattern is being executed (NO in Step S 21 ), the movement controller  203  and the difficulty level setting unit  204  execute Steps S 5 -S 8  and Steps S 10 -S 12 . On the other hand, when the movement controller  203  has determined in Step S 21  that the execution of the swing pattern has been completed (YES in Step S 21 ), the difficulty level setting unit  204  performs processing of adjusting the difficulty level in Steps S 22 -S 24 . 
     In Step S 22 , the difficulty level setting unit  204  refers to the difficulty level down flag. When the difficulty level down flag is 0, processing is continued again from the processing of Step S 3  without changing the difficulty level of the swing pattern. On the other hand, when the difficulty level setting unit  204  has determined in Step S 22  that the difficulty level down flag is 1, the difficulty level setting unit  204  determines whether the difficulty level of the swing pattern currently selected by the movement controller  203  is equal to or larger than 2 (Step S 22 ). When the difficulty level is equal to or larger than 2, the difficulty level setting unit  204  updates the difficulty level of the swing pattern selected by the movement controller  203  to a value obtained by reducing one from the current value (Step S 23 ). On the other hand, when it is determined in Step S 22  that the difficulty level is smaller than 2, the difficulty level setting unit  204  maintains the difficulty level of the swing pattern selected by the movement controller  203  to be the current value (NO in Step S 22 ) since the difficulty level cannot be further reduced. After the update processing in Step S 24  or the difficulty level maintenance determination processing in Step S 23  has been completed, the training apparatus  100  continues the processing in series from the processing of Step S 3 . 
     The change in the difficulty level when the operation along the flowchart shown in  FIG. 5  is performed will be explained using a timing chart.  FIG. 6  shows a liming chart for describing the change in the difficulty level of the training in the training apparatus according to the first embodiment. The example shown in  FIG. 6  shows an operation of the training apparatus  100  over a period in which the swing pattern is executed twice. Further, the example shown in  FIG. 6  shows an example in which the swing pattern of the difficulty level  5  is selected in the first swing pattern cycle, and then the difficulty level of the swing pattern is lowered to 4 in the next swing pattern cycle since the trainee  900  can no longer maintain his/her posture. 
     In the example shown in  FIG. 6 , from timing T 0  to timing T 3 , the first swing pattern cycle TB is executed. In the example shown in  FIG. 6 . at timing T 1 , the trainee  900  turns on the handrail switch. It becomes difficult for the trainee  900  to maintain his/her posture when the difficulty level of the training exceeds his/her ability. In this case, the trainee  900  maintains his/her posture by holding the handrail  162  while pushing this handrail switch  310 . Then at timing T 2 , the handrail ON counter exceeds the first specified value. Accordingly, at timing T 2 , the difficulty level down flag is rewritten from 0 to 1. Then, at a timing later than the timing T 2 , the trainee  900  releases his/her hand from the handrail switch  310 , whereby the handrail ON counter is reset to zero. However, the difficulty level down flag rewritten to 1 at timing T 2  maintains 1 until the swing pattern cycle at timing T 3  is completed. 
     Then, at the time of switching of the swing pattern cycle TB at timing T 3 , the difficulty level setting unit  204  reduces the difficulty level of the swing pattern selected by the movement controller  203  by one since the difficulty level down flag is 1. 
     Further, in the example shown in  FIG. 6 , from timing T 3  to timing T 8 , the second swing pattern cycle TB is executed. In the example shown in  FIG. 6 , at timing T 4 , the trainee  900  turns on the handrail switch. However, in the second swing pattern cycle TB in which the difficulty level has been reduced, the trainee  900  releases his/her hand from the handrail switch  310  at timing T 5 . Accordingly, at timing T 5 , the value of the handrail ON counter is reset to zero. After that, at timing T 6 , the trainee  900  turns on the handrail switch  310  again. After that, when the state in which the trainee  900  turns on the handrail switch  310  is maintained, the handrail ON counter exceeds the first specified value at timing T 7 . Therefore, at timing T 7 , the difficulty level down flag is rewritten from 0 to 1. At a timing later than timing T 7 , the trainee  900  releases his/her hand from the handrail switch  310 , whereby the handrail ON counter is reset to zero. However, the difficulty level down flag rewritten to 1 at timing T 7  is maintained to be 1 until the swing pattern cycle at timing T 8  is completed. 
     Then, at the time of switching of the swing pattern cycle TB at timing T 8 , the difficulty level setting unit  204  reduces the difficulty level of the swing pattern selected by the movement controller  203  by one since the difficulty level down flag is 1. 
     From the aforementioned description, with the training apparatus  100  according to the first embodiment, in the active load training for actively operating the moving cart  110  in accordance with the swing pattern, the handrail switch  310  is provided in the handrail that the trainee  900  uses as a support to maintain his/her posture when the difficulty level of the training is higher than the ability of the trainee  900 . Then the strength of the training is reduced or maintained based on the length of the period of a state during which the ON state of the handrail switch  310  during the training is maintained. 
     From the above discussion, in the training apparatus  100  according to the first embodiment, when the difficulty level of the training provided for the trainee  900  is high, the difficulty level of the training can be reduced to a difficulty level that matches the ability of the trainee  900 . Further, in the training apparatus  100  according to the first embodiment, the difficulty level is gradually reduced starting from the swing pattern whose difficulty level is the highest. Therefore, it becomes possible to enable the trainee  900  to perform training in which the difficulty level that the trainee  900  can deal with in view of his/her ability is maintained to be as high as possible. 
     Further, since the swing patterns are stored in the memory  240  in advance, the training apparatus  100  according to the first embodiment needs not generate a swing pattern in accordance with the difficulty level of the training by operations. Further, in the training apparatus  100  according to the first embodiment, the handrail switch  310  is provided in the handrail  162 , whereby even in a situation in which it is difficult for the trainee  900  to maintain his/her posture, it becomes easy for the trainee  900  to maintain his/her posture while pushing the handrail switch  310 . 
     Second Embodiment 
     In a second embodiment, another method of determining the disturbance of the posture of the trainee  900  for changing the difficulty level of the training will be explained.  FIG. 7  shows a timing chart for describing a change in the difficulty level of the training in a training apparatus according to the second embodiment. 
     In the training apparatus  100  according to the second embodiment, the difficulty level setting unit  204  reduces the difficulty level when an integrated value within a predetermined period of time of the time when the handrail switch  310  is in the ON state becomes equal to or larger than a certain rate with respect to the predetermined period of time. That is, the difficulty level setting unit  204  according to the second embodiment reduces the difficulty level when the integrated value of the time in a state in which the disturbance of the state of the trainee  900  regarding which a notification is sent from the posture detection sensor  250  has become outside a predetermined range exceeds a predetermined rate within a determination threshold period having a predetermined length. 
     In the example shown in  FIG. 7 , the length of one swing pattern cycle TB is set as a predetermined period of time (e.g.. determination threshold period). Then, in the example shown in  FIG. 7 , the handrail switch  310  becomes the ON state intermittently during a period from timing T 10  when the swing cycle pattern TB is started to timing T 11 . The difficulty level setting unit  204  integrates the period of a state during which the handrail switch  310  is in the ON state. At timing T 11 , the difficulty level down flag is set to 1 since the integrated value has exceeded a predetermined determination threshold. Accordingly, at timing T 12  at which the swing pattern is switched to the next cycle, the difficulty level of the swing pattern selected by the movement controller  203  is reduced. 
     From the aforementioned description, the determination method for determining that it is not appropriate for the trainee  900  to continue training at the current difficulty level in view of the disturbance of the posture of the trainee  900  can be changed, for example, depending on the specification of the training apparatus  100  or the type of the training, not only by the determination method according to the first embodiment shown in  FIG. 6 . The cases in which the disturbance of the posture that makes the handrail switch  310  be switched intermittently to the ON state as shown in  FIG. 7  includes, for example, a case in which the ability of the trainee  900  is slightly lower than the difficulty level of the training. In this case, by employing the determination method according to the second embodiment, it becomes possible to provide training at an appropriate difficulty level for a trainee whose determination regarding whether to switch the difficulty level of the training is difficult as well. 
     Third Embodiment 
     In a third embodiment, an operation method in which processing for increasing the difficulty level of the training is added, besides processing for decreasing the difficulty level of the training, will be explained.  FIG. 8  shows a flowchart for describing an operation of a training apparatus  100  according to the third embodiment. 
     As shown in  FIG. 8 , in the training apparatus  100  according to the third embodiment. Steps S 2  and S 22  in the flowchart according to the first embodiment shown in  FIG. 5  are replaced by Steps S 41  and S 42 . In Step S 41 , the initial difficulty level of the training is set, and at the same time the value of the difficulty level up counter newly set in the training apparatus  100  according to the third embodiment is reset to zero. Step S 42  is the difficulty level up processing. The difficulty level up processing is processing performed by the difficulty level setting unit  204 . In the difficulty level up processing, the difficulty level is increased when the duration period of a slate during which disturbance of the state of the trainee  900  regarding which a notification is sent from the posture detection sensor  250  is within a predetermined range has become equal to or larger than the difficulty level increase determination period set based on the second specified value. The detailed processing of the difficulty level up processing will be described below. 
       FIG. 9  shows a flowchart for describing an operation of the difficulty level up processing of the training apparatus according to the third embodiment. In  FIG. 9 , in order to describe the relation between the difficulty level up processing (Step S 42 ) and processing before and after this processing, process steps before and after the difficulty level up processing are described as well. 
     As shown in  FIG. 9 , the difficulty level up processing is performed when it is determined in Step S 21  that the execution of the swing pattern has been completed. In the difficulty level up processing, it is first determined whether the difficulty level down flag is 1 (Step S 51 ). When it is determined in Step S 51  that the difficulty level down flag is 1 (YES in Step S 51 ), the difficulty level setting unit  204  resets the difficulty level up counter to zero and determines the value of the difficulty level shown in Step S 23  (Step S 52 ). 
     On the other hand, when it is determined in Step S 51  that the difficulty level down flag is 0 (NO in Step S 51 ), the difficulty level setting unit  204  performs processing of increasing the value of the difficulty level up counter by one (Step SS 3 ). Alter that, the difficulty level setting unit  204  compares the value of the difficulty level up counter with a predetermined second specified value (Step S 54 ). When it is determined in Step S 54  that the value of the difficulty level up counter is equal to or smaller than the second specified value (NO in Step S 54 ), the difficulty level setting unit  204  performs the processing of Step S 3  as the next processing. On the other hand, when it is determined in Step S 54  that the value of the difficulty level up counter is larger than the second specified value (YES in Step S 54 ), the difficulty level setting unit  204  determines whether the current difficulty level is equal to or smaller than 4 (Step S 55 ). 
     When it is determined in Step S 55  that the current difficulty level is larger than 4 (NO in Step S 55 ), the difficulty level setting unit  204  performs the processing of Step S 3  as the next processing. On the other hand, when it is determined in Step S 55  that the current difficulty level is equal to or smaller than 4 (YES in Step S 5 S), the difficulty level setting unit  204  increases the current difficulty level by one and resets the difficulty level up counter to zero (Step S 56 ). Then, after the processing of Step S 56  is completed, the difficulty level setting unit  204  performs the processing of Step S 3  as the next processing. 
     In the example shown in  FIG. 9 , the difficulty level increase determination period is determined by (he product of the execution period of one swing pattern cycle and the second specified value. 
     From the aforementioned description, the training apparatus  100  according to the third embodiment is able to not only decrease the difficulty level of the training but also increase the difficulty level of the training when the trainee  900  has succeeded in the training for a plurality of swing pattern cycles. Accordingly, the training apparatus  100  according to the third embodiment is able to provide training at a more appropriate difficulty level for the trainee  900 . 
     Fourth Embodiment 
     In a fourth embodiment, another method of determining the disturbance of the posture of the trainee  900  for changing the difficulty level of the training will be explained.  FIG. 10  shows a timing chart for describing a change in the difficulty level of the training in a training apparatus according to the fourth embodiment. 
     As shown in  FIG. 10 , in a training apparatus  100  according to the fourth embodiment, processing of Step S 61  is added to the flowchart of the operation of the training apparatus  100  according to the first embodiment shown in  FIG. 5 . Step S 61  is processing performed after the processing of Step S 12 . In Step S 61 , the difficulty level setting unit  204  determines whether the handrail ON counter is equal to or larger than a third specified value. This third specified value is set to be a value larger than the first specified value. When it is determined in Step S 61  that the value of the handrail ON counter is larger than the third specified value (YES in Step S 61 ), the difficulty level setting unit  204  instructs the movement controller  203  to stop the moving cart  110  and to stop the training. On the other hand, when it is determined in Step S 61  that the value of the handrail ON counter is equal to or smaller than the third specified value (NO in Step S 61 ), the difficulty level setting unit  204  executes the processing of Step S 8  as the next processing. 
     By providing the processing of Step S 61 , the training apparatus  100  according to the fourth embodiment detects a state in which the trainee  900  maintains his/her posture while holding the handrail switch  310  or the handrail  162  for a period of time longer than the time specified by the first specified value. It can be determined from the state of the trainee  900  that the difficulty level of the training is much higher than the ability of the trainee  900 . Therefore, in the training apparatus  100  according to the fourth embodiment, in a case in which it can be determined that the difficulty level of the training is much higher than the ability of the trainee  900 , the training can be forcibly stopped by the processing of Step S 61 . Accordingly, with the training apparatus  100  according to the fourth embodiment, it is possible to provide training at an appropriate difficulty level for the training apparatus  100  and to increase the safety. 
     Other Embodiments 
     In other embodiments, another form of the arrangement of the posture detection sensor  250  sensors that can be used as the posture detection sensor  250  will be explained. In the following description, the respective forms will be described as fifth to eighth embodiments. 
       FIG. 11  shows a schematic view for describing a function of a training apparatus according to a fifth embodiment. In a training apparatus  100  according to the fifth embodiment, handrail switches are provided in a plurality of respective sides of the handrail  162  that is provided to surround the trainee  900 . In the training apparatus  100  according to the fifth embodiment shown in  FIG. 11 , the frame  160  located on the back side of the trainee  900  in a state in which the front of the body of the trainee  900  faces the forward traveling direction of the moving cart  110  is denoted by a frame  160   a.  Then a handrail  162  of the frame  160   a  is provided with a handrail switch  330 . 
     As described above, by providing a plurality of handrail switches in the handrail that surrounds the trainee  900 , it becomes possible for the trainee  900  to stably maintain his/her posture when he/she loses his/her posture. 
       FIG. 12  shows a schematic view for describing a function of a training apparatus according to a sixth embodiment. In a training apparatus  100  according to the sixth embodiment, a pressure sensor  350  is used as the posture detection sensor  250 . As shown in  FIG. 12 , the pressure sensor  350 , which is provided between the frame  160  and a handrail  340 , detects the pressure applied to the handrail  340  when the trainee  900  holds the handrail  340 . 
     As described above, by using the pressure sensor  350  as the posture detection sensor  250 . regardless of the position of the handrail  340  the trainee  900  holds, the disturbance of the posture of the trainee  900  can be detected. 
       FIG. 13  shows a schematic view for describing a function of a training apparatus according to a seventh embodiment. In a training apparatus  100  according to the seventh embodiment, a biological sensor  360  is used as the posture detection sensor  250 . As shown in  FIG. 13 , the biological sensor  360  is a wearable terminal attached to a part in the vicinity of the wrist of the trainee  900 . Further, the biological sensor  360  communicates with the difficulty level setting unit  204  provided in the control box ISO by radio communication. In  FIG. 13 , a reception unit  370  is shown as an interface that performs communication between the biological sensor  360  and the difficulty level setting unit  204 . 
     The biological sensor  360  is, for example, a sensor that detects at least one of the heart rate, the respiration rate, the tidal volume, and the perspiration amount in a palm or the like of the trainee  900 . When the biological sensor  360  is used, the difficulty level setting unit  204  counts up the value that corresponds to the handrail ON counter (the name is not limited to a “handrail ON counter”) when the value detected by the biological sensor  360  exceeds a predetermined threshold. 
     By using the biological sensor  360  as described above, even when disturbance of the posture of the trainee  900  does not occur, it is possible to detect that an excessive load is applied to the trainee  900  and to provide training at a more appropriate difficulty level for the trainee  900 . 
       FIG. 14  shows a schematic view for describing a function of a training apparatus according to an eighth embodiment. In a training apparatus  100  according to the eighth embodiment, a camera  380  is used as the posture detection sensor  250 . In the example shown in  FIG. 14 , the camera  380  is attached to an upper end part of the frame  160 , or the handrail  162 . The camera  380  captures an image of the trainee  900 . The image captured by the camera  380  may be the trainee  900  himself/herself, or may be an image indicating the skeleton or distribution of body temperature of the trainee  900 . When the camera  380  is used, image processing is performed in the camera  380  or the difficulty level setting unit  204 , whereby a feature image indicating the posture of the trainee  900  is generated, and the disturbance of the posture of the trainee  900  is detected based on the generated feature image. 
     When the feet of the trainee  900  is caused to swing, the trainee  900  performs operations such as vigorously raising his/her arms while leaning back or vigorously putting his/her arms forward while bending his/her upper body forward in order to balance himself/herself. By using the camera  380 , the motions of the upper body and the upper limb of the trainee  900  are detected, and when, for example, the operation speed of the upper limb exceeds a specified value, it is determined that the training at a difficulty level that is above the ability of the trainee  900  is being provided. In this case, the difficulty level of the training can be decreased. 
     By using the camera  380  as described above, it is possible to determine whether the difficulty level of the training provided for the trainee  900  is appropriate using the reaction made by the trainee  900  who does not hold the handrail. 
     A (The) program can be stored and provided to a computer using any type of non-transitory computer readable media. Non-transitory computer readable media include any type of tangible storage media. Examples of non-transitory computer readable media include magnetic storage media (such as floppy disks, magnetic tapes, hard disk drives, etc.), optical magnetic storage media (e.g. magneto-optical disks), CD-ROM (compact disc read only memory), CD-R (compact disc recordable), CD-R/W (compact disc rewritable), and semiconductor memories (such as mask ROM, PROM (programmable ROM), EPROM (erasable PROM), flash ROM, RAM (random access memory), etc.). The program may be provided to a computer using any type of transitory computer readable media. Examples of transitory computer readable media include electric signals, optical signals, and electromagnetic waves. Transitory computer readable media can provide the program to a computer via a wired communication line (e.g. electric wires, and optical fibers) or a wireless communication line. 
     From the disclosure thus described, it will be obvious that the embodiments of the disclosure may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure, and all such modifications as would be obvious to one skilled in the art are intended for inclusion within the scope of the following claims.