Abstract:
A multidirectional foot controller includes a base, a movable platform, a rotatable platform, and two pedals successively stacked and assembled together. The multidirectional foot controller is activated by having the two pedals depressed simultaneously, and then controls an externally connected endoscope to move forward or backward by means of a movable platform, or controls the endoscope to move leftward or rightward by means of a rotatable platform. By having only one of the pedals depressed, the multidirectional foot controller can change the field of view of the endoscope. The resultant multidirectional operation helps to improve working efficiency and operational stability.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to foot controllers, and more particularly to a multidirectional foot controller suitable for positioning an endoscope. 
         [0003]    2. Description of Related Art 
         [0004]    In the process of minimally invasive surgery using endoscope, for fast adjustment of the endoscope&#39;s field of view, while keeping the endoscope stable, a robotic arm is typically employed to provide structural support to the endoscope. The operating surgeon operates a foot controller to move the robotic arm that in turn places the endoscope as needed. 
         [0005]    Such a foot controller, as disclosed in U.S. Pat. No. 7,058,998, may use plural buttons to activate different functions. However, the known device has some of the buttons provided on the same panel, and tends to lead to users&#39; wrong stepping. Furthermore, since some of the buttons are located near edges of the controller&#39;s base, it is likely that the user&#39;s foot slips off the keys and failed operation is caused. Hence, the prior-art device needs to be improved for better operational convenience and stability. 
       BRIEF SUMMARY OF THE INVENTION 
       [0006]    The primary objective of the present invention is to provide a multidirectional foot controller, which allows multidirectional operation, while providing good operational stability and accuracy. 
         [0007]    To achieve the foregoing objective, the disclosed multidirectional foot controller comprises a base, two first position detecting switches, two second position detecting switches, a movable platform, a rotatable platform, and two pedals. The two first position detecting switches are located at front and rear ends of the base. The two second position detecting switches are located at left and rear sides of the base. The movable platform is such slidably installed on the top surface of the base so that it can move forward or backward with respect to the base. When the movable platform moves to the end of its travel, it touches one of the first position detecting switches, and starts to control a robotic arm to drive an endoscope to move forward or backward. The rotatable platform is such pivotally installed on the top surface of the movable platform so that it can rotate leftward or rightward with respect to the movable platform. When the rotatable platform to the end of its rotational range, it touches one of the second position detecting switches, and starts to control the robotic arm to drive the endoscope to move leftward or rightward. The two pedals are tandem arranged on the top surface of the rotatable platform, for a user to depress and thereby make the movable platform move forward or backward and make the rotatable platform to rotate leftward or rightward. 
         [0008]    Thereby, the disclosed multidirectional foot controller can use the movable platform to move the endoscope forward or backward, and use the rotatable platform to move the endoscope leftward or rightward. Additionally, the endoscope&#39;s field of view can be sized by the user&#39;s stepping on a single. The resultant multidirectional operation helps to improve working efficiency and operational stability. 
         [0009]    In one embodiment of the present invention, the base has a lower housing, an immovable platform, and at least two rollers. The immovable platform is placed on the top surface of the lower housing. The two rollers are arranged at two ends of the immovable platform. The two first position detecting switches are located at front and rear ends of the lower housing. The two second position detecting switches are located at left and rear sides of the lower housing. The movable platform is stacked on the top surface of the immovable platform. The movable platform has its bottom surface provided with at least two roller tracks. Each of the roller tracks abuts against one said roller. Thereby, the movable platform can slide forward or backward on the base in virtue of the rollers. 
         [0010]    In one embodiment of the present invention, the movable platform has its top surface provided with a first pivot portion. The rotatable platform has its bottom surface provided with a second pivot portion. The first and second pivot portions are pivotally connected through a bearing, so that the rotatable platform can rotate leftward or rightward with respect to the movable platform. In addition, a torsion spring is provided between the rotatable platform and the movable platform, so that the rotatable platform after intended rotation can be returned to its initial position by the torsion spring. 
         [0011]    In one embodiment of the present invention, the movable platform has a lower curved groove, and the rotatable platform has an upper curved groove. The upper and lower curved grooves jointly receive a guiding member passing therethrough. The guiding member has one end fixed to the rotatable platform, so that the rotatable platform can move more stably with the support from the guiding member. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0012]      FIG. 1  is a perspective view of the present invention. 
           [0013]      FIG. 2  is an exploded view of the present invention. 
           [0014]      FIG. 3  is a partial, cross-sectional of the present invention. 
           [0015]      FIG. 4  is a side view of the present invention, showing the tandem pedals are depressant simultaneously. 
           [0016]      FIG. 5  is a top view of the present invention, showing the rotatable platform rotating rightward. 
           [0017]      FIG. 6  is similar to  FIG. 5  but shows the rotatable platform rotating leftward. 
           [0018]      FIG. 7  is a side view of the present invention, showing the movable platform moving forward. 
           [0019]      FIG. 8  is similar to  FIG. 7  but shows the movable platform moving backward. 
           [0020]      FIG. 9  is a side view of the present invention, showing the front pedal pressed. 
           [0021]      FIG. 10  is similar to  FIG. 9  but shows the rear pedal pressed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]    Referring to  FIG. 1  and  FIG. 2 , in one embodiment of the present invention, a multidirectional foot controller  10  comprises a base  20 , two first position detecting switches  30 , two second position detecting switches  40 , a movable platform  50 , a rotatable platform  60 , and two pedals  70 . 
         [0023]    The base  20  has an upper housing  21 , a lower housing  22 , an immovable platform  23 , and a plurality of rollers  25 . The upper housing  21  has a window  24 . The lower housing  22  is assembled to the upper housing  21  from below. The immovable platform  23  is fixed to the top surface of the lower housing  22 . The rollers  25  are evenly distributed at the front and rear ends of the immovable platform  23 . 
         [0024]    The first position detecting switches  30  as shown are limit switches that are fixed to the front and rear ends of the lower housing  22  of the base  20  through two first switch holders  32 . 
         [0025]    The second position detecting switch  40  as shown are limit switches that are fixed to the left and rear sides of the lower housing  22  of the base  20  through two second switch holders  42 . 
         [0026]    The movable platform  50  is assembled to the top surface of the immovable platform  23 , and, as shown in  FIG. 3 , the front and rear ends of the bottom surface of the movable platform  50  has two roller tracks  51 . Each of the roller tracks  51  accommodates with two rollers  25 , so that the movable platform  50  are allowed to move forward or backward with respect to the base  20  by means of the rollers  25 . Additionally, the front end of the movable platform  50  has a front protrusion  52 . The rear end of the movable platform  50  has a rear protrusion  53  and a first pivot portion  54  near the rear protrusion  53 . Each of the front and rear protrusions  52 ,  53  positionally corresponds to one of the first position detecting switches  30 . 
         [0027]    The rotatable platform  60  is assembled to the top surface of the movable platform  50 . The rotatable platform  60  at its bottom surface near its rear end has a second pivot portion  61 . The second pivot portion  61  is pivotally connected to the first pivot portion  54  of the movable platform  50  through a bearing  62 , so that the rotatable platform  60  can on one hand rotate leftward or rightward with respect to the movable platform  50  and on the other hand drive the movable platform  50  to move forward or backward with respect to the base  20 . Moreover, the left and rear sides of the rotatable platform  60  are provided with a left protrusion  63  and a right protrusion  64 , respectively. Each of the left and right protrusions  63 ,  64  positionally corresponds to one of the second position detecting switches  40 . 
         [0028]    For allowing the rotatable platform  60  to automatically return to its original position after rotation, a torsion spring  65  is mounted around the first pivot portion  54  of the rotatable platform  60 . As shown in  FIG. 2  and  FIG. 3 , the torsion spring  65  has its two ends connected to the movable platform  50  and the rotatable platform  60 , respectively, so that the torsion spring  65  provides a returning force to the rotatable platform  60 . Also, as shown in  FIG. 2  and  FIG. 3 , the movable platform  50  has its front end provided with a lower curved groove  55 , and the rotatable platform  60  has its front end provided with an upper curved groove  66 . A guiding member  80  is placed in the upper and lower curved grooves  65 ,  55 . The guiding member  80  has a shaft  82 , a fixed block  84 , and an idler  86 . The shaft  82  passes through the upper curved groove  66  of the rotatable platform  60  and the lower curved groove  55  of the movable platform  50 . The fixed block  84  is connected to the top end of the shaft  82  and is fixed to the top surface of the rotatable platform  60 . The idler  86  is rotatably connected to the bottom end of the shaft  82  and rollably abuts against the wall of the lower curved groove  55  of the movable platform  50 . Thereby, the guiding member  80  moves along the upper and lower curved grooves  65 ,  55  as the rotatable platform  60  rotates, so as to further ensure stable movement of the rotatable platform  60 . 
         [0029]    The two pedals  70  are tandem and symmetrically arranged on the top surface of the rotatable platform  60 , and are exposed at the window  24  of the upper housing  21  of the base  20 , for a user to step. 
         [0030]    Furthermore, the disclosed multidirectional foot controller  10  has a circuit board  90  that is fixed to the lower housing  22  of the base  20  and located below the immovable platform  23 . The circuit board  90  is electrically communicated with the pedals  70 , the first position detecting switches  30 , and the second position detecting switches  40  simultaneously, so as to process the signals from the pedals  70 , the first position detecting switches  30 , and the second position detecting switches  40 , thereby allowing the disclosed multidirectional foot controller  10  to drive a robotic arm (not shown) that in turn drives an endoscope (not shown) under the control of an operating surgeon for minimally invasive surgery. 
         [0031]    In use, the two pedals  70  are simultaneously depressed to turn on the controller (as shown in  FIG. 4 ). Then, for controlling a robotic arm to drive an endoscope to move leftward or rightward, a user may selectively use the two pedals  70  to directly make the rotatable platform  60  rotate leftward or rightward. When the rotatable platform  60  has its left protrusion  63  or right protrusion  64  touching the second position detecting switch  40 , as shown in  FIG. 5  and  FIG. 6 , the robotic arm is controlled to make the endoscope move leftward or rightward. When the endoscope reaches the intended site, the left protrusion  63  or the right protrusion  64  of the rotatable platform  60  is operated to leave the second position detecting switch  40  it previously contacted. At this time, the robotic arm stops moving and the placement of the endoscope is finished. On the other hand, for controlling the robotic arm to drive the endoscope to move forward or backward, the user may operate the pedals  70  and in turn the rotatable platform  60  to drive the movable platform  50  to move forward or backward. When the front protrusion  52  or the rear protrusion  53  of the movable platform  50  touches the first position detecting switch  30 , as shown in  FIG. 7  and  FIG. 8 , the robotic arm can be controlled to drive the endoscope to move forward or backward. When the endoscope reaches the intended site, the front protrusion  52  or the rear protrusion  53  of the movable platform  50  is moved away from the first position detecting switch  30  it previously contacted, so the robotic arm stops moving and the placement of the endoscope is finished. Moreover, for sizing the field of view of the endoscope through the robotic arm, as shown in  FIG. 9  and  FIG. 10 , the user may release the force he/she applies to one of the pedals  70 , meaning that only one of the pedals  70  is depressed. When the endoscope&#39;s field of view is well adjusted, the user once again steps on the both pedals  70 , so as to further control the movable platform  50  and the rotatable platform  60 . 
         [0032]    To sum up, the disclosed multidirectional foot controller  10  uses the forward and backward movements of the movable platform  50 , the single-axis rotation of the rotatable platform  60 , and the up and down movements of the pedals  70  to provide a multidirectional operation mode. This allows a user to operate an endoscope through a robotic arm more stably, thereby improving working efficiency and operational precision.