Automatic velocity control treadmill using pressure sensor array and fuzzy-logic

Abstract

The present invention relates to an automatic speed-controlled treadmill using a pressure sensor array and a method of operating the same. The automatic speed-controlled treadmill includes a walking belt, a pressure sensor array including pressure sensors for detecting loads of the exerciser's feet and outputting the detected loads of the feet as load detection signals, a pace speed status storage unit for storing a pace speed and variation in pace speed of the exerciser, and a control unit provided with an algorithm for calculating a pace speed of the exerciser using the load detection signals, calculating a difference between a previous pace speed and a current pace speed as the variation in pace speed, calculating the exercise center of the exerciser, and proportionally accelerating/decelerating a driving speed of the walking belt in consideration of the variation in pace speed and the exercise center.

1 . An automatic speed-controlled treadmill using a pressure sensor array, comprising: a walking belt disposed on a bottom of the treadmill and configured to function as a pace surface of an exerciser; a pressure sensor array comprising pressure sensors for detecting loads of the exerciser's feet and outputting the detected loads of the feet as load detection signals, the pressure sensors being disposed in a plurality of arrangements between the bottom of the treadmill and the walking belt; a pace speed status storage unit for storing a pace speed and variation in pace speed of the exerciser who takes exercise on the walking belt; and a control unit provided with an algorithm for receiving the load detection signals from the pressure sensors and then calculating a pace speed of the exerciser, calculating a difference between a previous pace speed and a current pace speed as the variation in pace speed, calculating the exercise center of the exerciser from unique position values of the pressure sensors, and proportionally accelerating/decelerating a driving speed of the walking belt in consideration of the variation in pace speed and the exercise center. 
   
   
       2 . (canceled) 
   
   
       3 . The automatic speed-controlled treadmill according to  claim 1 , wherein the pressure sensor array comprises:
 a right pressure sensor array provided on a right side of a longitudinal center line of the walking belt and configured to detect a load of a right foot of the exerciser; and a left pressure sensor array provided on a left side of the longitudinal center line of the walking belt and configured to detect a load of a left foot of the exerciser.   
   
   
       4 . The automatic speed-controlled treadmill according to  claim 1 , wherein the pressure sensors have respective unique position values indicating positions thereof. 
   
   
       5 . The automatic speed-controlled treadmill according to  claim 1 , wherein the pace speed is obtained by dividing a pace distance, indicating a distance between paces of the exerciser, by a pace time period, indicating a time period of inter-pace movement of the exerciser (the pace=the pace distance/the pace time period). 
   
   
       6 . The automatic speed-controlled treadmill according to  claim 5 , wherein, assuming that ‘an average lifting position=(a right foot lifting position+a left foot lifting position)/2’ and ‘an average stepping position=(a right foot stepping position+a left foot stepping position)/2’, the pace distance is obtained by ‘the pace distance=the average stepping position−the average lifting position’. 
   
   
       7 . The automatic speed-controlled treadmill according to  claim 5 , wherein, assuming that ‘an average lifting time point=(a right foot lifting time point+a left foot lifting time point)/2’ and ‘an average stepping time point=(a right foot stepping time point+a left foot stepping time point)/2’, the pace time period is obtained by ‘the pace time period=an average stepping time point−an average lifting time point’. 
   
   
       8 . The automatic speed-controlled treadmill according to  claim 1 , wherein, assuming that ‘an average lifting position=(a right foot lifting position+a left foot lifting position)/2’ and ‘the average stepping position=(a right foot stepping position+a left foot stepping position)/2’, the exercise center is obtained by ‘the exercise center=(the average stepping position+the average lifting position)/2’ 
   
   
       9 . The automatic speed-controlled treadmill according to  claim 1 , wherein the control unit accelerates the driving speed of the walking belt in steps as the variation in pace speed becomes higher and the exercise center becomes closer to a front portion of the walking belt, and decelerates the driving speed of the walking belt in steps as the variation in pace speed becomes lower and the exercise center becomes closer to a rear portion of the walking belt. 
   
   
       10 . A method of controlling a driving speed of a treadmill using a pressure sensor array, the method comprising:
 a first step of driving a walking belt of a treadmill through input manipulation of an exerciser; a second step of receiving load detection signals from pressure sensors for a first block, with a foot pace, including four positions (a left foot stepping position, a right foot stepping position, a left foot lifting position, and a left foot stepping position), being set to each block; a third step of, for the first block, calculating a pace speed of the exerciser using the load detection signals, calculating a difference between a previous pace speed and a current pace speed as variation in pace speed, and calculating an exercise center using unique position values of the pressure sensors; a fourth step of proportionally accelerating/decelerating the driving speed of the walking belt in consideration of the calculated variation in pace speed and the calculated exercise center; and a fifth step of receiving the load detection signals from the pressure sensors for a next block until the walking belt is stopped, and repeating the third step and the fourth step.   
   
   
       11 . The speed control method according to  claim 10 , wherein the pace speed is obtained by dividing a pace distance, indicating a distance between paces of the exerciser, by a pace time period, indicating a time period of inter-pace movement of the exerciser (the pace speed=the pace distance/the pace time period). 
   
   
       12 . The speed control method according to  claim 11 , wherein, assuming that ‘an average lifting position=(a right foot lifting position+a left foot lifting position)/2’ and ‘an average stepping position=(a right foot stepping position+a left foot stepping position)/2’, the pace distance is obtained by ‘the pace distance=the average stepping position−the average lifting position’. 
   
   
       13 . The speed control method according to  claim 11 , wherein, assuming that ‘an average lifting time point=(a right foot lifting time point+a left foot lifting time point)/2’ and ‘the average stepping time point=(a right foot stepping time point+a left foot stepping time point)/2’, the pace time period is obtained by ‘the pace time period=the average stepping time point−the average lifting time point’. 
   
   
       14 . The speed control method according to  claim 10 , wherein, assuming that ‘an average lifting position=(a right foot lifting position+a left foot lifting position)/2’ and ‘the average stepping position=(a right foot stepping position+a left foot stepping position)/2’, the exercise center is obtained by ‘the exercise center=(the average stepping position+the average lifting position)/2’. 
   
   
       15 . The speed control method, according to  claim 10 , wherein the control unit accelerates the driving speed of the walking belt in steps as the variation in pace speed becomes higher and the exercise center becomes closer to a front portion of the walking belt, and decelerates the driving speed of the walking belt in steps as the variation in pace speed becomes lower and the exercise center becomes closer to a rear portion of the walking belt. 
   
   
       16 . An automatic speed-controlled treadmill using a pressure sensor array, comprising: a walking belt disposed on a bottom of a treadmill and configured to function as a pace surface of an exerciser; a pressure sensor array comprising pressure sensors for detecting loads of the exerciser's feet and outputting the detected loads of the feet as load detection signals, the pressure sensors being disposed in a plurality of arrangements between the bottom of the treadmill and the walking belt; a pace speed status storage unit for storing a pace speed and variation in pace speed of the exerciser who takes exercise on the walking belt; and a control unit provided with an algorithm for receiving the load detection signals from the pressure sensors and then calculating the pace speed of the exerciser, calculating a difference between a previous pace speed and a current pace speed as the variation in pace speed, calculating an exercise center of the exerciser from unique position values of the pressure sensors, and proportionally accelerating/decelerating the driving speed of the walking belt based on a fuzzy theory using a fuzzifier, a rule base, a fuzzy inference engine, and a defuzzifier. 
   
   
       17 . The automatic speed-controlled treadmill according to  claim 16 , wherein the pressure sensor array comprises:
 a right pressure sensor array provided on a right side of a longitudinal center line of the walking belt and configured to detect a load of a right foot of the exerciser; and a left pressure sensor array provided on a left side of the longitudinal center line of the walking belt and configured to detect a load of a left foot of the exerciser.   
   
   
       18 . The automatic speed-controlled treadmill according to  16 , wherein the pressure sensors have respective unique position values indicating positions thereof. 
   
   
       19 . The automatic speed-controlled treadmill according to  claim 16 , wherein the pace speed is obtained by dividing a pace distance, indicating a distance between paces of the exerciser, by a pace time period, indicating a time period of inter-pace movement of the exerciser (the pace=the pace distance/the pace time period). 
   
   
       20 . The automatic speed-controlled treadmill according to  claim 16 , wherein, assuming that ‘an average lifting position=(a right foot lifting position+a left foot lifting position)/2’ and ‘the average stepping position=(a right foot stepping position+a left foot stepping position)/2’, the exercise center is obtained by ‘the exercise center=(the average stepping position+the average lifting position)/2’. 
   
   
       21 . The automatic speed-controlled treadmill according to  claim 16 , wherein the control unit accelerates the driving speed of the walking belt in steps as the variation in pace speed becomes higher and the exercise center becomes closer to a front portion of the walking belt, and decelerates the driving speed of the walking belt in steps as the variation in pace speed becomes lower and the exercise center becomes closer to a rear portion of the walking belt.