Patent ID: 11938629
Assignee: JIANGNAN UNIVERSITY
Field: Medical technology (Instruments)
Classification: CPC A  B  H | IPC B

Claim 7:
8. The micro-robot control method based on double closed loop three-dimensional path tracking according to claim 7, wherein the inputting the rotating magnetic field into an established current closed loop magnetic field controller to output a desired magnetic field comprises:
analyzing, by the current closed loop magnetic field controller, a direction of the rotating magnetic field and a coil output current fed back by the current sensor to output the control signal to the PWM inverter circuit, and outputting, by the PWM inverter circuit, a desired current to the Helmholtz coil to generate the desired magnetic field,, B
   =
   
    
     [
     
      
       
        
         B
         X
        
       
      
      
       
        
         B
         Y
        
       
      
      
       
        
         B
         Z
        
       
      
     
     ]
    
    =
    
     
      
       
        
         B
         0
        
        ⁢
        
         cos
         ⁡
         (
         
          2
          ⁢
          
           π
           ⁢
           ft
          
         
         )
        
       
       
        
         
          n
          x
          2
         
         +
         
          n
          y
          2
         
        
       
      
      [
      
       
        
         
          n
          y
         
        
       
       
        
         
          -
          
           n
           x
          
         
        
       
       
        
         0
        
       
      
      ]
     
     +
     
      
       
        
         B
         0
        
        ⁢
        
         sin
         ⁡
         (
         
          2
          ⁢
          
           π
           ⁢
           ft
          
         
         )
        
       
       
        
         
          
           (
           
            
             n
             y
            
            ⁢
            
             n
             z
            
           
           )
          
          2
         
         +
         
          
           (
           
            
             -
             
              n
              y
             
            
            ⁢
            
             n
             z
            
           
           )
          
          2
         
         +
         
          
           (
           
            
             -
             
              n
              x
              2
             
            
            -
            
             n
             y
             2
            
           
           )
          
          2
         
        
       
      
      [
      
       
        
         
          
           n
           y
          
          ⁢
          
           n
           z
          
         
        
       
       
        
         
          
           -
           
            n
            y
           
          
          ⁢
          
           n
           z
          
         
        
       
       
        
         
          
           -
           
            n
            x
            2
           
          
          -
          
           n
           y
           2
          
         
        
       
      
      ]
     
    
   
  
  ,
 

wherein BX, BY, and BZ are components of a magnetic field B in three axial directions, and nx, ny and nz are unit direction quantities of three planes, comprising an XOY plane, an XOZ plane, and a YOZ plane; and
decomposing a magnetic field into three axes, comprising an X axis, a Y axis, and a Z axis, a mapping relationship between a magnetic field and a current between the axes being as follows:, B
   =
   
    
     
      (
      
       4
       5
      
      )
     
     
      3
      2
     
    
    ⁢
    
     
      
       μ
       0
      
      ⁢
      NI
     
     a
    
   
  
  ,
 

wherein μ0 is a magnetic field dielectric constant, N represents the number of turns of each Helmholtz coil, a represents a radius of the Helmholtz coil, and I represents the desired current flowing into the coil.