Posture estimation method, posture estimation device, and vehicle

Abstract

A posture estimation method includes calculating a posture change amount of an object based on an output of an angular velocity sensor, predicting posture information of the object by using the posture change amount, adjusting error information in a manner of determining whether or not the output of the angular velocity sensor is within an effective range and, when it is determined that the output of the angular velocity sensor is not within the effective range, increasing a posture error component in error information and reducing a correlation component between the posture error component and an error component other than the posture error component in the error information, and correcting the predicted posture information of the object based on the error information.

What is claimed is: 
     
         1 . A posture estimation method comprising:
 calculating a posture change amount of an object based on an output of an angular velocity sensor;   predicting posture information of the object by using the posture change amount;   adjusting error information in a manner of determining whether or not the output of the angular velocity sensor is within an effective range, and when it is determined that the output of the angular velocity sensor is not within the effective range, increasing a posture error component in error information and reducing a correlation component between the posture error component and an error component other than the posture error component in the error information; and   correcting the predicted posture information of the object based on the error information.   
     
     
         2 . The posture estimation method according to  claim 1 , wherein
 the adjusting of the error information includes
 determining whether or not a current time is in a first period after it is determined that the output of the angular velocity sensor is not within the effective range, 
 increasing the posture error component in the first period, and 
 reducing the correlation component between the posture error component and the error component other than the posture error component, in the first period. 
   
     
     
         3 . The posture estimation method according to  claim 1 , wherein
 the error component other than the posture error component includes a bias error component of an angular velocity.   
     
     
         4 . The posture estimation method according to  claim 2 , wherein
 the error component other than the posture error component includes a bias error component of an angular velocity.   
     
     
         5 . The posture estimation method according to  claim 1 , wherein
 the correlation component between the posture error component and the error component other than the posture error component is zero.   
     
     
         6 . The posture estimation method according to  claim 1 , further comprising:
 calculating a velocity change amount of the object based on an output of an acceleration sensor and the output of the angular velocity sensor, wherein   in the adjusting of the error information, whether or not the output of the acceleration sensor is within an effective range is determined, and, when it is determined that the output of the angular velocity sensor or the output of the acceleration sensor is not within the corresponding effective range, a motion velocity error component in the error information is increased, and a correlation component between the motion velocity error component and an error component other than the motion velocity error component in the error information is reduced, and   in the predicting of the posture information, velocity information of the object is predicted by using the velocity change amount.   
     
     
         7 . The posture estimation method according to  claim 6 , wherein
 the adjusting of the error information includes
 determining whether or not a current time is in a second period after it is determined that the output of the acceleration sensor is not within the effective range, 
 increasing the motion velocity error component in the second period, and 
 reducing the correlation component between the motion velocity error component and the error component other than the motion velocity error component, in the second period. 
   
     
     
         8 . The posture estimation method according to  claim 6 , wherein
 the error component other than the motion velocity error component includes a bias error component of an acceleration.   
     
     
         9 . The posture estimation method according to  claim 7 , wherein
 the error component other than the motion velocity error component includes a bias error component of an acceleration.   
     
     
         10 . The posture estimation method according to  claim 6 , wherein
 the correlation component between the motion velocity error component and the error component other than the motion velocity error component is zero.   
     
     
         11 . A posture estimation device comprising:
 a posture-change-amount calculation unit that calculates a posture change amount of an object based on an output of an angular velocity sensor;   a posture information prediction unit that predicts posture information of the object by using the posture change amount;   an error information adjustment unit that determines whether or not the output of the angular velocity sensor is within an effective range, and when it is determined that the output of the angular velocity sensor is not within the effective range, increases a posture error component in error information, and reduces a correlation component between the posture error component and an error component other than the posture error component in the error information; and   a posture information correction unit that corrects the predicted posture information of the object based on the error information.   
     
     
         12 . A vehicle comprising:
 the posture estimation device according to  claim 11 ; and   a control device that controls a posture of the vehicle based on posture information of the vehicle, which is estimated by the posture estimation device.