Instrument for compensating for hand tremor during the manipulation of fine structures

Abstract

The invention relates to an instrument for the manipulation of fine structures, said instrument detecting hand tremor and compensating for this hand tremor by effecting counter-movements of the working tip. The main area of application will probably lie in the field of microsurgery, since the operations performed in said field can be made difficult by the hand tremor of the operating surgeon. Here, the tremor is detected by movement sensors, by repeated analysis of the position of the handheld part ( 1 ) of the instrument, or by deriving electromyographic signals from the forearm of the operator. Intentional and unintentional movements are differentiated from one another on the basis of one or more criteria, such as movement amplitude, speed, frequency and direction. To compensate for undesired movements, signals are sent to an arrangement of actuators ( 3 ) which cause deflections of the movable part ( 4 ) of the instrument, which deflections at the tip of the instrument compensate for the hand tremor. When the instrument is used as a needle holder in surgery, the actuators ( 3 ) can also be controlled by push button in such a way that, by oscillations, they facilitate the penetration of the suture needle into the area being worked on.

1 . Instrument for the manual working of fine structures, consisting of 
 (a) a handheld section ( 1 ),    (b) a section ( 4 ) which is movable in relation to the handheld section ( 1 ),    (c) actuators ( 3 ), and where    (d) the actuators ( 3 ) are designed to effect relative movements between the handheld section ( 1 ) and the movable section ( 4 ), which relative movements compensate at least partially for movements of the handheld section ( 1 ).    
     
     
         2 . Instrument according to    claim 1   , characterized in that one or more sensors ( 2 ) are arranged on the handheld section ( 1 ), said sensors ( 2 ) detecting the movement of the handheld section ( 1 ), and their output signal being used to trigger the actuators ( 3 ).  
     
     
         3 . Instrument according to    claim 1    or    2   , characterized in that one or more sensors are arranged on the movable section ( 4 ), said sensors detecting the movement of the movable section ( 4 ), and their output signal being used to trigger the actuators ( 3 ).  
     
     
         4 . Instrument according to one of claims  1  through  3 , characterized in that one or more sensors are arranged on the handheld section ( 1 ) or on the movable section ( 4 ) or between the handheld section ( 1 ) and the movable section ( 4 ), said sensors detecting the relative movement between the handheld section ( 1 ) and the movable section ( 4 ), and their output signal being used to trigger the actuators ( 3 ).  
     
     
         5 . Instrument according to one of claims  2  through  4 , characterized in that at least one sensor detects the acceleration.  
     
     
         6 . Instrument according to one of claims  1  through  5 , characterized in that one or more sensors are provided for repetitive or continuous detection of the position of the handheld section ( 1 ) in one, two or three dimensions.  
     
     
         7 . Instrument according to one of claims  1  through  6 , characterized in that one or more sensors are provided for repetitive or continuous detection of the position of the movable section ( 4 ) in one, two or three dimensions.  
     
     
         8 . Instrument according to    claim 6    or    7   , characterized in that the position of the instrument is detected optically via the ray path of an operating microscope.  
     
     
         9 . Instrument according to one of claims  1  through  8 , characterized in that a control or regulating unit triggers the actuators on the basis of the data from the sensors for position detection and/or movement detection.  
     
     
         10 . Instrument according to one of claims  1  through  9 , characterized in that a control or regulating unit triggers the actuators on the basis of a repetitive or continuous position detection.  
     
     
         11 . Instrument according to one of claims  1  through  10 , characterized in that electromyographically detected potentials are used to trigger the actuators.  
     
     
         12 . Instrument according to one of claims  1  through  11 , characterized in that when movements of the handheld section or movable section occur, the compensation movements take place in a predetermined or adjustable or automatically adapting frequency range.  
     
     
         13 . Instrument according to one of claims  1  through  12 , characterized in that when movements of the handheld section or movable section occur, the compensation movements take place in a predetermined or adjustable or automatically adapting amplitude range.  
     
     
         14 . Instrument according to one of claims  1  through  13 , characterized in that the actuators ( 3 ) can be triggered in such a way that a rigid connection is obtained between the handheld section ( 1 ) and the movable section ( 4 ).  
     
     
         15 . Instrument according to one of claims  1  through  14 , characterized in that the actuators ( 3 ) can be triggered in such a way that they can generate oscillations of the movable section ( 4 ).