Abstract:
A mechanism effectively mimics human facial expressions for use in animated characters. On the front surface of the mechanism, four gears, meshed in pairs, provide rotational surfaces for a series of cranks and pins. As the gears rotate, the cranks and pins engage a loop of elastomeric material. As pin distance from each other, the loop stretches. As pins approach each other, the loop contracts. Other pins located on the cranks or gears cause an inflection or deflection of the loop as the gears rotate. The resulting stretch or bending of the loop more accurately and efficiently mimics facial expressions.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application claims the priority of U.S. Provisional Application Ser. No. 60/381,722 entitled “Expressive Feature Mechanism for Animated Characters and Devices” filed on May 17, 2002 and application PCT/US03/15120 filed on May 14, 2003, the entire contents and substance of which are hereby incorporated in total by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a mechanical apparatus used to cause various expressions on the face of an animated character. 
   2. Description of Related Art 
   This invention pertains to an expressive feature mechanism used in an animated character. The goal of this invention is to achieve a full range of human-like and recognizable facial expressions. This goal has been addressed by others and has often led to the development of devices used in animated characters that have mouths, which open and close to mimic speaking or sucking. An example of such work would be U.S. Pat. No. 4,808,142 by Berliner, which has a motor driven mouth actuator to move the mouth between open and closed positions. 
   U.S. Pat. No 2,250,916 by Magruder uses electromagnetic coils to animate the upper and lower lip in synchrony to sound. 
   U.S. Pat. No. 3,841,020 by Ryan employs a complex set of levers and actuators that allow a range of facial expressions related to the motion of a doll&#39;s arms. 
   U.S. Pat. No. 3,828,469 by Giroud describes a mechanism having two operating rods for moving upper and lower lips. 
   More recently issued patents describe techniques that allow for a greater control of lip motion. For example, U.S. Pat. No. 6,352,464 by Madland et al. describes a mechanism for an animated character. The Madland Patent describes a facial control system comprising two lip chains embedded behind two lips. The lip chains are attached at either end as well as at a center portion. By positioning the movable center portion relative to the moveable ends various facial expressions can be achieved, however, the described mechanism does not allow for stretching of the lips as it occurs on human and animal faces. 
   Other methods such as the one described in U.S. Pat. No. 4,177,589 by Villa include a pneumatic mechanism to open and close the mouth. That method allows for a rounding of the lips but does not allow for a full range of expression such as a frown or broad smile. 
   Mechanisms such as U.S. Pat. No. 6,544,098 by Hampton are capable of some recognizable expressions but only with the addition of other actions such as drooping ears or closing eyes. 
   Other devices of possible relevance are described in the following U.S. Pat. Nos. 4,294,033; 4,805,328; 5,376,040; 6,386,942 and 6,503,123. 
   The current invention comprises an improved means to make animated characters with complex facial expressions in a minimal component, minimal cost, highly efficient mechanism. This mechanism improves upon the mechanism described in the previously submitted U.S. Provisional Application Ser. No. 60/381,722 and PCT/US03/15120 filed May 14, 2003 by allowing stretch of the lip member beyond the radius of the primary drive wheels. This improved design creates a more recognizable expression with the added benefit of a more compact design per breadth of smile. 
   SUMMARY OF INVENTION 
   Briefly described, the invention comprises of a pair of wheels or meshed gears used to generate human-like expressions. On each wheel or gear there is a lever driven attachment point and a device for inflecting or deflecting an elastomeric or flexible material or device. The primary goal of the wheels or gears is to directly stretch or allow for contraction of the elastomeric or flexible material or device attached to a point along a radius, or to drive a series of levers to stretch or allow for contraction of the elastomeric or flexible material. Meshing of the gears allows for a reduction of drive sources while maintaining bilateral symmetry of motion. Independent wheels allow for asymmetric motion. In a meshed gear mechanism, one gear and its attachment point mirror the other in the pair. If one gear in the pair turns clockwise, the other gear in the pair turns counterclockwise. Since attachment points mirror each other on each gear of a pair, rotation of the pair would either increase or decrease the distance between each attachment point. An elastomeric or flexible material or device encircling the attachment points stretches or contracts as the gears turn. The inflection/deflection devices offer an increase in the recognition of an exaggerated expression produced by the bending of the elastomeric or flexible material or device. 
   The elastomeric or flexible material or device can comprise a variety of conformations, ranging from a continuous band to a molded mask hiding and yet attached to the entire mechanism. The transmission of movement from the gears or levers to the elastomeric or flexible material or device may also occur via indirect coupling such as magnetism. 
   The invention advantageously provides a moving lip mechanism for animated characters or devices that is efficient in its design and construction. The device is capable of producing a range of motions in a range of speeds able to simulate a variety of expressions and mouth movements. With the synchronization of sound the device can simulate smooth, realistic vocalization. 
   This invention will be described further with reference to the following drawings. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
       FIG. 1   a  is an isometric view of the preferred embodiment showing a pair of dual gear, single drive mechanisms using motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIG. 1   b  is an isometric view with the support platform removed from the preferred embodiment showing a pair of dual gear, single drive mechanisms and employing motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIGS. 1   c - 1   e  are additional orthogonal views of the preferred embodiment showing a pair of dual gear, single drive mechanisms and employing motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIG. 2  is a isometric view of the preferred embodiment showing only a single drive and gearing assembly. 
       FIGS. 3   a - 3   f  are various top views showing the gear arrangement and relative position of the attachment points and inflection/deflection points to present the elastomeric material in a human-like expression. 
       FIG. 4   a  is an isometric view showing a pair of dual gear, single drive mechanisms using motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIG. 4   b  is an isometric view with support platforms removed showing a pair of dual gear, single drive mechanisms employing motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIGS. 4   c - 4   e  are additional orthogonal views showing a pair of dual gear, single drive mechanisms using motors with non-integrated encoding with the elastomeric material in place around attachment points on each of the gears and gear driven link mechanisms. 
       FIG. 5   a  is a top view showing a mechanism, utilizing slotted links on both the upper and lower portions of the mechanism. 
       FIG. 5   b  is an isometric view showing a mechanism, utilizing slotted links on both the upper and lower portions of the mechanism. 
       FIG. 6   a  is a top view showing a mechanism, utilizing slotted links on both the upper and lower portions of the mechanism. 
       FIG. 6   b  is an isometric view showing a mechanism, utilizing links on both the upper and lower portions of the mechanism. 
       FIGS. 7   a - 7   f  are various top plan views showing the gear arrangement and relative position of the attachment points and inflection/deflection points to present the elastomeric material in an expression. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   During the course of this description, like numbers will be used to identify like elements according to the different views that illustrates the invention. 
   Referring to  FIGS. 1   a - 1   e , the mechanism  10 , according to the preferred embodiment, comprises a lower motor support platform  119 , an upper motor support platform  118  and a gear support platform  117 . The motor support platform secures two motors  120  and  122 , also referred to as a drive means, which in turn have small motor drive gears  124  and  126  respectively attached to their perspective drive shafts. Gears  124  and  126  mesh with reduction gears  128  and  130  respectively. The reduced diameters of reduction gears  128  and  130  mesh with primary expression driving gears  132  and  134  respectively. Expression diving gears are also referred to as rotatable means. Positional sensing of the primary expression driving gear  132  is achieved by variable resistance or positional contacts on the control board  140  in a manner known to those of ordinary skills in the art. It is understood that other commercial means of encoding of position would be equally effective in positional sensing. Magnetic encoding, transmission slots counting, and reflective encoding are examples of other common methods of rotational encoding. Primary expression driving gears  132  and  134  in turn mesh with secondary expression driving gears  144  and  146  respectively. Expression driving gears  132  and  134  have one drive pin each affixed to a point on their surface. Expression driving gears  144  and  146  have two drive pins each affixed to points in relation to the radius of each respective expression driving gear. Expression driving gears  144  and  146  drive pins are at a fixed degree apart from one another. In the case of primary expression driving gear  132 , it has attachment drive pin  160  and inflection-deflection drive pin  166  affixed. In the case of primary expression driving gear  144 , it has attachment drive pin  162  and inflection-deflection drive pin  164  affixed. In the case of primary expression driving gear  134 , it has a link drive pin  204  affixed. In the case of primary expression driving gear  146 , it has a link drive pin  206  affixed. Rotation of gears  134  and  146  causes link drive pins  204  and  206  to push or pull inflection-deflection links  216  and  218 . The pushing or pulling of inflection-deflection links  216  and  218  in turn causes the pivoting of links  200  and  202  on fulcrums  212  and  214  respectively. Links  200  and  216  together form the first crank means. Links  202  and  218  together form the second crank means Affixed to links  200  and  204  are attachment points  156  and  158  which also serve as fulcrum points for inflection links  216  and  218  respectively. Affixed to links  216  and  218  are inflection-deflection points  168  and  170  respectively. Fitted around the four attachment points is elastomeric material  180 , also referred to as an elastic loop means. To prevent the return rotation of the primary and secondary expression driving gears, gearlocks  182  and  184  fits into the teeth of secondary expression driving gears  144  and  146  respectively. Gearlock  182  is allowed to release secondary expression driving gear  144  by having shaft  186  pulled by solenoid  190  and pivoted on its axis. Gearlock  184  is allowed to release secondary expression driving gear  146  by having shaft  188  pulled by solenoid  192  and pivoted on its axis. 
     FIG. 1   a  illustrates an isometric view of the preferred embodiment of the mechanism  10 . In this view, the attachment points  156 ,  158 ,  160 , and  162  for holding the elastomeric material  180  represent lips, in a smiling expression. In the preferred embodiment, power to the motors  120  and  122  (see also  FIG. 1   b ) is not applied once the desired position is sensed by control board  140 . Instead, position is maintained against the pull of elastomeric material  180  by securing the drive gears  144  and  146  against rotation with the gearlocks  182  and  184  (see also  FIG. 1   b ). Rotation of the motors and change in expression of  10  as represented by the position of  180  is allowed by the activation of solenoids  190  and  192 , see also  FIG. 1   b , and the pull back of respective gearlocks  182  and  184 . 
     FIG. 1   b  shows the same isometric view of the preferred embodiment as  FIG. 1   a  but with the removal of support platforms  117 , 118 , 119  and circuit board  140  for clarity, see also  FIG. 1   a.    
     FIG. 1   c  and  FIG. 1   d  also illustrate the preferred embodiment and show a right side and back view respectively of the mechanism  10 . These views give clear perspectives of the relative positions of reduction gears  128  and  130  to their meshed small motor drive gears  124  and  126  and primary expression driving gears  132  and  134 . 
     FIG. 1   e  also describes the preferred embodiment and illustrates a top plan view of the mechanism  10 . This view would be the side that faces forward and represents the mouth of an animated character or design. 
     FIG. 2  illustrates in a detail view a single motor and drive system for the preferred embodiment. The portion shown is the upper right quadrant of the facial expression system. 
     FIGS. 3   a - 3   f  illustrates examples of expression driving gear arrangements and their effect on the elastomeric material  180  stretched around the attachment points  156 ,  158 ,  160  and  162 .  FIG. 3   a ,  FIG. 3   b  and  FIG. 3   c  show arrangements approximating a smile.  FIG. 3   d  shows the mechanism at rest.  FIG. 3   e - FIG. 3   f  shows arrangements emulating sadness and anger. 
   DETAILED DESCRIPTIONS OF ALTERNATE EMBODIMENTS 
   Referring to  FIGS. 4   a - 4   e , the mechanism  20 , according to an alternate embodiment, comprises a lower motor support platform  319 , an upper motor support platform  318  and a gear support platform  317 . The motor support platform secures two motors  320  and  322 , which in turn have small motor drive gears  324  and  326  respectively attached to their perspective drive shafts. Gears  324  and  326  mesh with reduction gears  328  and  330  respectively. The reduced diameters of reduction gears  328  and  330  mesh with primary expression driving gears  332  and  334  respectively. Positional sensing of the primary expression driving gear  332  is achieved by variable resistance or positional contacts on the control board  340 . It is understood that other commercial means of encoding of position would be equally effective in positional sensing. Magnetic encoding, transmission slots counting, and reflective encoding are examples of other common methods of rotational encoding. Primary expression driving gears  332  and  334  in turn mesh with secondary expression driving gears  344  and  346  respectively. Each expression driving gear has two drive pins affixed to points in relation to the radius of each respective expression driving gear. Each gear&#39;s drive pins are at a fixed degree apart from one another. In the case of primary expression driving gear  332 , it has attachment drive pin  360  and inflection-deflection drive pin  366  affixed. In the case of primary expression driving gear  344 , it has attachment point  362  and inflection-deflection drive pin  364  affixed. In the case of primary expression driving gear  334 , it has a link drive pin  404  and inflection-deflection drive pin  420  affixed. In the case of primary expression driving gear  346 , it has a link drive pin  406  and inflection-deflection drive pin  422  affixed. Rotation of gears  334  and  346  cause link drive pins  404  and  406  to pivot links  400  and  402  as they travel through slots  408  and  410  respectively. Pivoting of links  400  and  402  on fulcrums  412  and  414  then cause inflection-deflection links  416  and  418  to be pulled outward or pushed inward guided by drive pins  420  and  422  respectively. Links  400  and  416  together form the first crank means. Links  402  and  418  together form the second crank means Affixed to links  400  and  402  are attachment points  356  and  358  which also serve as fulcrum points for inflection links  416  and  418  respectively. Affixed to links  416  and  418  are inflection-deflection points  368  and  370  respectively. Fitted around the four attachment points is elastomeric material  380 . To prevent the return rotation of the primary and secondary expression driving gears, gearlocks  382  and  384  fits into the teeth of secondary expression driving gears  344  and  346  respectively. Gearlock  382  is allowed to release secondary expression driving gear  344  by having shaft  386  pulled by solenoid  390  and pivoted on its axis. Gearlock  384  is allowed to release secondary expression driving gear  346  by having shaft  388  pulled by solenoid  392  and pivoted on its axis. 
     FIG. 4   a  is an isometric view of the alternate embodiment of the mechanism  20 . In this view, the attachment points  356 ,  358 ,  360 , and  362  for holding the elastomeric material  380  represent lips, in a smiling expression. In the alternate embodiment, power to the motors  320  and  322  (see also  FIG. 4   b ) is not applied once the desired position is sensed by control board  340 . Instead, position is maintained against the pull of elastomeric material  380  by securing drive gears  344  and  346  against rotation with the gearlocks  382  and  384  (see also  FIG. 4   b ). Rotation of the motors and a change in expression of  20  as represented by the position of  380  is governed by the activation of solenoids  390  and  392 , see also  FIG. 4   b , and the pull back of respective gearlocks  382  and  384 . 
     FIG. 4   b  shows the same isometric view of the alternate embodiment as  FIG. 4   a  but with the removal of support platforms  317 ,  318 ,  319  and circuit board  340  for clarity, see also  FIG. 4   a.    
     FIG. 4   c  and  FIG. 4   d  also describe the alternate embodiment and show a right side and back view of the mechanism  20 . These views give clear perspectives of the relative positions of reduction gears  328  and  330  to their meshed small motor drive gears  324  and  326  and primary expression driving gears  332  and  334 . 
     FIG. 4   e  describes the alternate embodiment and illustrates a top plan view of the mechanism  20 . This view would be the side that faces forward and represents the mouth of an animated character or design. 
     FIG. 5   a  is a top plan view of an alternate embodiment of the mechanism  30 . This view illustrates the side that faces forward and represents the mouth of an animated character or design. 
     FIG. 5   b  is an isometric view of an alternate embodiment of the mechanism  30 . In this view, the attachment points  356 ,  358 ,  454 , and  456  for holding the elastomeric material  380  represent lips, in a form suggestive of smiling expression. 
     FIGS. 5   a - 5   b  together provide top and isometric views respectively of a mechanism using pin and slot driven links on both the upper and lower gear pairs to enhance the motion of elastomeric material  380 . The mechanism  30  is identical to the mechanism  20  with the exception of the four links and their associated drive pin locations and attached pins. By utilizing pin and slot driven links on both the upper and lower gear pairs a more comical expression can be achieved. In practice, this method has more novelty applications since the human frown is at a greater arc than a human smile. With this in mind, lower links would not be in the preferred embodiment but should be included as a method for other novelty devices and characters. Referring to  FIGS. 5   a - 5   b , the mechanism  30 , according to this alternate embodiment, comprises a lower motor support platform  319 , an upper motor support platform  318  and a gear support platform  317 . The motor support platform secures two motors  320  and  322 , which in turn have small motor drive gears  324  and  326  respectively attached to their perspective drive shafts. Gears  324  and  326  mesh with reduction gears  328  and  330  respectively. The reduced diameters of reduction gears  328  and  330  mesh with primary expression driving gears  332  and  334  respectively. Positional sensing of the primary expression driving gear  332  is achieved by variable resistance or positional contacts on the control board  340 . It is understood that other commercial means of encoding of position would be equally effective in positional sensing. Magnetic encoding, transmission slots counting, and reflective encoding are examples of other common methods of rotational encoding. Primary expression driving gears  332  and  334  in turn mesh with secondary expression driving gears  344  and  346  respectively. Each expression driving gear has two drive pins affixed to points in relation to the radius of each respective expression driving gear. Each gear&#39;s drive pins are at a fixed degree apart from one another. In the case of primary expression driving gear  332 , it has link drive pin  436  and inflection-deflection drive pin  452  affixed. In the case of primary expression driving gear  344 , it has link drive pin  434  and inflection-deflection drive pin  450  affixed. In the case of primary expression driving gear  334 , it has a link drive pin  404  and inflection-deflection drive pin  420  affixed. In the case of primary expression driving gear  446 , it has a link drive pin  406  and inflection-deflection drive pin  422  affixed. Rotation of gears  334  and  346  cause link drive pins  404  and  406  to pivot links  400  and  402  as they travel through slots  408  and  410  respectively. Pivoting of links  400  and  402  on fulcrums  412  and  414  then cause inflection-deflection links  416  and  418  to be pulled outward or pushed inward guided by drive pins  420  and  422  respectively. Links  400  and  416  together form the first crank means. Links  402  and  418  together form the second crank means Affixed to links  400  and  402  are attachment points  356  and  358  which also serve as fulcrum points for inflection links  416  and  418  respectively. Affixed to links  416  and  418  are inflection-deflection points  368  and  370  respectively. Rotation of gears  332  and  344  cause link drive pins  434  and  436  to pivot links  430  and  432  as they travel through slots  438  and  440  respectively. Pivoting of links  430  and  432  on fulcrums  442  and  444  then cause inflection-deflection links  446  and  448  to be pulled outward or pushed inward guided by drive pins  450  and  452  respectively. Links  430  and  446  together form the third crank means. Links  432  and  448  together form the forth crank means Affixed to links  430  and  432  are attachment points  454  and  456  which also serve as fulcrum points for inflection links  446  and  448  respectively. Affixed to links  446  and  448  are inflection-deflection points  458  and  460  respectively. Fitted around the four attachment points is elastomeric material  380 . To prevent the return rotation of the primary and secondary expression driving gears, gearlocks  382  and  384  fit into the teeth of secondary expression driving gears  344  and  346  respectively. Gearlock  382  is allowed to release secondary expression driving gear  344  by having shaft  386  pulled by solenoid  390  and pivoted on its axis. Gearlock  384  is allowed to release secondary expression driving gear  346  by having shaft  388  pulled by solenoid  392  and pivoted on its axis. 
     FIG. 6   a  is a top plan view of an alternate embodiment of the mechanism  40 . This view illustrates the side that faces forward and represents the mouth of an animated character or design. 
     FIG. 6   b  is an isometric view of an alternate embodiment of the mechanism  40 . In this view, pins  168 ,  170 ,  246  and  248  are contacting the outside of elastomeric material loop  180 . The attachment points  156 ,  158 ,  242 , and  244  are stretching from the inside of elastomeric material loop  180 . The stretching and bending of the elastomeric material  180 , representing lips, form an expression suggestive of a smirk. 
     FIGS. 6   a - 6   b  together provide top and isometric views respectively of a mechanism using links on both the upper and lower gear pairs to enhance the motion of elastomeric material  180 . The mechanism  40  is identical to the mechanism  10  with the exception of the four links and their associated drive pin locations and attached pins. Referring to  FIGS. 6   a - 6   b , the mechanism  40 , according to this alternate embodiment, comprises a lower motor support platform  119 , an upper motor support platform  118  and a gear support platform  117 . The motor support platform secures two motors  120  and  122 , which in turn have small motor drive gears  124  and  126  respectively attached to their perspective drive shafts. Gears  124  and  126  mesh with reduction gears  128  and  130  respectively. The reduced diameters of reduction gears  128  and  130  mesh with primary expression driving gears  132  and  134  respectively. Positional sensing of the primary expression driving gear  132  is achieved by variable resistance or positional contacts on the control board  140 . It is understood that other commercial means of encoding of position would be equally effective in positional sensing. Magnetic encoding, transmission slots counting, and reflective encoding are examples of other common methods of rotational encoding. Primary expression driving gears  132  and  134  in turn mesh with secondary expression driving gears  144  and  146  respectively. Each expression driving gear has a single drive pin affixed. In the case of primary expression driving gear  132 , it has link drive pin  240  affixed. In the case of primary expression driving gear  144 , it has link drive pin  238  affixed. In the case of primary expression driving gear  134 , it has a link drive pin  204  affixed. In the case of primary expression driving gear  146 , it has a link drive pin  206  affixed. Rotation of gears  134  and  146  causes link drive pins  204  and  206  to push or pull inflection-deflection links  216  and  218 . The pushing or pulling of inflection-deflection links  216  and  218  in turn causes the pivoting of links  200  and  202  on fulcrums  212  and  214  respectively. Links  200  and  216  together form the first crank means. Links  202  and  218  together form the second crank means Rotation of gears  144  and  132  causes link drive pins  238  and  240  to push or pull inflection-deflection links  234  and  236  respectively. The pushing or pulling of inflection-deflection links  234  and  236  in turn causes the pivoting of links  230  and  232  on fulcrums  250  and  252  respectively. Links  230  and  234  together form the third crank means. Links  232  and  236  together form the forth crank means Affixed to links  200  and  204  are attachment points  156  and  158  which also serve as fulcrum points for inflection links  216  and  218  respectively. Affixed to links  216  and  218  are inflection-deflection points  168  and  170  respectively. Affixed to links  230  and  232  are attachment points  242  and  244  which also serve as fulcrum points for inflection links  234  and  236  respectively. Affixed to links  234  and  236  are inflection-deflection points  246  and  248  respectively. Fitted around the four attachment points is elastomeric material  180 . To prevent the return rotation of the primary and secondary expression driving gears, gearlocks  182  and  184  fit into the teeth of secondary expression driving gears  144  and  146  respectively. Gearlock  182  is allowed to release secondary expression driving gear  144  by having shaft  186  pulled by solenoid  190  and pivoted on its axis. Gearlock  184  is allowed to release secondary expression driving gear  146  by having shaft  188  pulled by solenoid  192  and pivoted on its axis. 
     FIGS. 7   a - 7   f  illustrate examples of expression driving gear arrangements for mechanism  20  and their effect on the elastomeric material stretched around the attachment points.  FIG. 7   a ,  FIG. 7   b  and  FIG. 7   c  show arrangements approximating a smile.  FIG. 7   d  shows the mechanism at rest.  FIG. 7   e - FIG. 7   f  shows arrangements emulating sadness and anger. 
   While the invention has been described with reference to the preferred embodiment thereof it will be appreciated by those of ordinary skill in the art that modifications can be made to the parts that comprise the invention without departing from the spirit and scope thereof.