Abstract:
The present invention includes controller coupled with actuators, swivel balanced arm holder with rotating head, location position information system that can maintain emitter of medical Emitter/Sensor Positioning System in desired position. This enables surgeon to reduce number of personnel in operating room, reduces the time of the surgery, makes incisions and cuts more precise.

Description:
BACKGROUND 
       [0001]    During surgeries surgeons are using emitter/sensor positioning system to properly locate/identify relative position of various body parts and surgical equipment, this enables the surgeon to perform correct incisions/cuts which increases the chance of successful operation and reduces the after surgery recovery time. Typical emitter /sensor positioning system is shown in  FIG. 1 . 
         [0002]    In this system  100  Sensors  106  and  108  are placed on the body parts or medical equipment. Emitter  102  emits signal  104  (electrical, electromagnetic, optical, radioactive, etc.), 
         [0003]    Multiple Sensors  106   108  sense the strength and type of signal and feed that signal information to Location/Position/Information System  110  (LPIS). LPIS  110  calculates/displays information about relative location of the Sensors  106   108 . Based on that information surgeon can perform medical device orientation, incision and cut location and direction. 
         [0004]    In this system position of the emitter  102  is critical, because detected signal strength by sensors  106  and  108  depends on it. Emitter  102  must be easily moved because of the movement and flexibility required during the operation and varying size and location of the patient. However it must maintain steady position to maintain accurate signal  104  for sensor positions. 
         [0005]    Presently to maintain proper position of the emitter  102 , surgeon&#39;s assistant holds it and moves it as required to maintain proper signal for sensors  106   108 . He has to follow movement of body parts or medical devices to which sensors  106   108  are attached. When there is no movement, he has to hold emitter  102  steady/motionless to prevent faulty location/position information. Alternatively there is an articulate lockable arm that holds emitter  102  in one position only, then surgeon has to unlock it to move to new position to follow the movement of the body parts or medical device, then he has to lock it again. Advantage of the lockable arm is that it is steady for motionless mode, but because it&#39;s lockable feature it is very hard to use when there are multiple motions of patient or medical device. Our invention reduces the surgery time, and recovery time for the patient. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a block diagram of typical emitter/sensor positioning system (existing setup) 
           [0007]      FIG. 2  is a block diagram of our invention with Emitter Positioning and Holding Automated Device System  200 . 
           [0008]      FIG. 3  is a block diagram of our invention with Control System for Automated Emitter Positioning and Holding Device System  300 . 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    We invented Emitter Positioning and Holding Automated Device System  200 . It consists of Swivel Balanced Arm Holder  210  with Rotating Head  214 , Actuators  208 , and Control System  206  (CS). Control System  206  reads Signals  202  from LPIS  110  and from Actuators  208  and/or from Assisted Input Unit  204  and controls Actuators  208  to set Emitter  102  into desired position. Diagram of the system is shown in  FIG. 2 . 
         [0010]    Swivel Balanced Arm  210  provides ability to adjust position of the head which holds Emitter  102  in X/Y/Z directions, since it is balanced it also can be used without actuators or control system in free motion/manual mode. 
         [0011]    Swivel Arm  210  can be mounted stationary near surgery table, or be on Powered Moving (wheeled) Platform  212  to provide even greater flexibility to adjust position of the holder in X/Y directions. Rotating Head  214  provides ability to adjust the angles along the X/Y/Z axis to maintain proper angles when Swivel Arm  210  moves. 
         [0012]    Assisted Open Loop Input  204  gives ability to move Emitter  102  into desired position by manually entering the desired location, it has individual controls for each coordinate X/Y/Z and each angle for the Balanced Arm Holder  210  and Rotating Head  214 . 
         [0013]    Control System  206  runs multiple proportional/integral/differential PID controllers to control actuators to achieve desired position of the Emitter  102 , based on the input either from LPIS  110  or Assisted/Open Loop input  204 . 
         [0014]    Actuators  208  can move Swivel Arm  210  and Rotating Head  214  into desired position. They can be simple hydraulic/pneumatic systems with valves, or electric DC/AC/permanent magnet motors or any other device that can move the portions of Swivel Arm  210  and Rotating Head  214 . 
       Modes of Operation 
       [0015]    Our system will operate in three distinct modes Manual, Semi-Automated, Automated.
       1. In Manual mode all Actuators  208  and Control System  206  are disabled. Emitter holder can be moved by simply moving the Holder Rotating Head  214 , since Swivel Arm  210  is balanced, Emitter  102  will be stable at any position it is moved.   2. In Semi-Automated mode Control System  206  controls Actuators  208  to the position based on the Assisted/Open Loop Input (AOLI)  204 . Surgeon has individual control of each degree of freedom for the holder and can request the direction and amount of the motion. Control System  206  will translate the request from AOLI  204  into various effort for each Actuator  208  and activate them to achieve requested motion like up/down, left/right, tilt/rotate.   3. In Automated mode Control System  206  moves Actuators  208  constantly to achieve optimized signals at Sensors  106   108 .       
 
       Control System and Algorithms 
       [0019]    Diagram describing the Control System operation  300  is shown in  FIG. 3 . Control System  206  uses microprocessor to perform activation of the each Actuator  322   328   334  based on the data from LPIS  110  and AOLI  204  and Actuators  322   328   334  actual position. Since the Swivel Arm  210  has various Actuators and their motion is not directly translated into X/Y/Z coordinates, Control System  206  calculates/translates desired position into control effort for each Actuator. It also employs the final element analysis and Limit Sensors  336  to prevent collision between Emitter  102  and surrounding objects (patient, equipment, personnel, etc.). It also reads back relative position  336  of each Actuator so coordinate translation can be done. 
         [0020]    Each Actuator  322   328   334  has its own control loop to control its effort/position. Control System  206  gets input in which mode to operate from Mode Input  302 . It calculates Desired Position  310   308   306  for each Actuator  322   328   334 . That desired position is fed into Proportional Integral Differential (PID) controllers  318   324   330  via at Error Calculating Blocks  312   314   316 , which subtracts actual position for each actuator from the desired position. PID controllers  318   324   330  calculate effort required to move the Actuators  322   328   334 . That effort gets amplified by Amplifiers  322   326   332  which will perform the move of Actuators  322   328   334 . Amplifiers  320   326   332  can be various type like hydraulic, pneumatic, electric motors, etc.