Abstract:
The invention relates to a method for implementing an automated hearing aid modeling system that is a computerized rule-based binaural modeling system which includes performing a hearing-aid class dependent processing on the hearing aid shell design. Features of the hearing aid shell are recognized and attributes associated with these features are stored. A rule-based product handling for the shell model is used that is determined based on a determined shell type. Global and local offsets are performed on data associated with the shell model, as is binaural processing to augmented detailing and modeling protocols used on the shell model. The hearing aid is created based on the shell model processed according to the preceding steps. An appertaining system for implementing the method is also provided.

Description:
BACKGROUND 
       [0001]    The present invention is directed towards the field of hearing aid modeling systems, and particularly towards a computerized rule-based binaural modeling system and appertaining method for hearing aid design. This application is related to U.S. patent application Ser. No. 11/612,616, filed Dec. 19, 2006, PCT Patent Application PCT/EP2006/061101, filed Mar. 28, 2006, [Michele, please insert filing information here for your ref. no. 2006 P 24545 US, “Method for Anatomically Aware Automatic Faceplate Placement Protocols for Hearing instrument Design”; and 2006 P 24294 US “System and Method for the Analysis of Basic Ear Canal Taxonomy”] and their respective priority applications, all herein incorporated by reference. 
         [0002]    Hearing aid design has historically been a manually intensive task and has relied on heuristics and ad hoc methods that had evolved over time. Recent advances in three-dimensional modeling technologies have lent themselves to the design of hearing aids, permitting a more robust and rule-based mechanism for hearing aid design that eliminates much of the guesswork that previously was utilized in the manual process. 
         [0003]    Abbreviations used herein are as follows:
   CA Canal hearing aid design   CIC Completely-in-canal hearing aid design   DWOM Digital work order management   HS Half shell hearing aid design   ITE In-the-ear (full shell) hearing aid design   MC Mini canal hearing aid design   
 
       SUMMARY 
       [0010]    The invention includes an embodiment which is a method for designing and building a hearing aid, comprising: entering a work order for a hearing aid which includes a digitized 3D shell model having feature data; performing at least one of smoothing, hole filling, outlier removal, and rendering based on the shell model; analyzing the shell model to recognize features and determine relevant parameters associated with the features; registering and storing, in a data store, the recognized features and associated parameters; implementing a rule-based protocol handling for the shell model that is determined based on a determined shell type; performing global and local offsets on data associated with the shell model; performing binaural processing to augmented detailing and modeling protocols used on the shell model; and creating a hearing aid based on the shell model processed according to the preceding steps. 
         [0011]    The invention further includes an embodiment including a computer system for automatically designing and building a hearing aid, comprising: a processor for executing software algorithms; an input and an output associated with the processor; a user interface device for accessing the processor; a memory for storing the software algorithms; wherein the software algorithms comprise: an algorithm for entering a work order for a hearing aid which includes a digitized 3D shell model having feature data; an algorithm for performing at least one of smoothing, hole filling, outlier removal, and rendering based on the shell model; an algorithm for analyzing the shell model to recognize features and determine relevant parameters associated with the features; an algorithm for registering and storing, in a data store, the recognized features and associated parameters; an algorithm for implementing a rule-based protocol handling for the shell model that is determined based on a determined shell type; an algorithm for performing global and local offsets on data associated with the shell model; and an algorithm for performing binaural processing to augmented detailing and modeling protocols used on the shell model. A further embodiment includes a computer readable media for storing executable code that implements the algorithms. 
         [0012]    The present system differs from other modeling system in the sense that it identifies characteristic features of the ear canal and defines rule based protocols for designing a customer hearing aid for the patient. This system combines feature recognition, buildability index computation (BIA) implementation and binaural processing to augmented detailing and modeling protocols. 
         [0013]    The embodiments of the invention develop advanced rule-based protocols to enable automatic modeling, detailing and component placement for ITE hearing instruments. Advanced automatic protocols are advantageous over manual protocols because they increase the quality of the ITE shell, allow for production time saving, and permit moving the shell modeling, detailing and component placement to the front-end of the process. The present invention can be integrated into other higher-level systems. 
         [0014]    The procedure defines the automatic protocols for automation of modeling, detailing and component placement of ITE shells, including the following categories described in more detail below: a) general rules; detailing rules for b) ITE, c) HS, d) CA, e) MC, f) CIC designs; g) rules for the receiver hole and vent; h) rules for component placement, and i) rules for collision detection. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0015]    The invention is explained by the following drawings and appertaining descriptive text below, which are illustrative of various embodiments of the invention. 
           [0016]      FIG. 1  is a block flow diagram illustrating a basic system overview of a Phase II implementation of rule-based binaural detailing and modeling; 
           [0017]      FIG. 2  is a block diagram illustrating cutting and detailing operations with required features that need to be feature recognized in order to accomplish the pertinent detailing operation; 
           [0018]      FIG. 3  is a 3D generated model illustrating an initial plane cut for all shells; 
           [0019]      FIG. 4  is a 3D generated model illustrating the transparent part of the shell that is the lower intertragal notch; 
           [0020]      FIG. 5  is a block diagram illustrating rule-based cuts and configurable cosmetic protocols for ITEs; 
           [0021]      FIG. 6  is a block diagram illustrating rule-based cuts for HSs; 
           [0022]      FIG. 7  is a 3D generated model illustrating a standard cut for CICs, MCs, CAs, and HSs (Crus_Cut_Round); 
           [0023]      FIG. 8  is a 3D generated model illustrating a Low_Angular_Cuts_Plane and shell Reduce_to_Device_Cut; 
           [0024]      FIG. 9  is a block diagram illustrating rule-based cuts for CICs; 
           [0025]      FIG. 10  is a pictorial diagram illustrating a receiver and vent channel configurations on a typical CIC and ITE shells; 
           [0026]      FIG. 11  is a pictorial block diagram illustrating reactional forces resulting from component interaction within the shell; and 
           [0027]      FIGS. 12A-F  are pictorial illustrations of faceplate orientations in various shell types. 
           [0028]      FIG. 13  is a pictorial illustration showing the battery door; 
           [0029]      FIG. 14A  is a pictorial illustration of a shell without an IROS cut; 
           [0030]      FIG. 14B  is a pictorial illustration of a shell with an IROS cut; 
           [0031]      FIG. 15A  is a pictorial illustration of a receiver and shell colliding; 
           [0032]      FIG. 15B  is a pictorial illustration of a receiver and shell that are avoiding a collision; 
           [0033]      FIG. 16  is a pictorial illustration of a shell in process “sitting” in a virtual cast; 
           [0034]      FIG. 17A  is a pictorial illustration of a push button; 
           [0035]      FIG. 17B  is a pictorial illustration of a volume control; 
           [0036]      FIG. 18  is a pictorial illustration of an alternate for canal cutting; and 
           [0037]      FIG. 19A , B are pictorial illustrations of an impression oriented so that the helix, concha, and canal openings are at a consistent height and parallel to the base of the impression. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0038]      FIG. 1  presents an overview of the system  10 . The present system  10  identifies characteristic features of the ear canal and defines rule based protocols for designing customer hearing aid for the patient. The flow begins with a work order for a hearing aid stored in a digital work order management system DWOM  12  (this system serves as an interface between modeling/detailing software and the business systems, defining the communications protocol) in which digitized 3D shell feature data is subjected to a tessellation module  20  that performs smoothing, hole filling, outlier removal, and rendering based on the shell model. 
         [0039]    The shell is then subjected to an analysis procedure  30  that includes feature recognition  32 , a registration of features  34 , a buildability index computation (BIA) implementation  36  as well as rule-based protocol handling  38 . Data is then provided to a global and local offset module  40  and the data is then subjected to binaural processing  42  to augmented detailing and modeling protocols, such as tapering  44 , rounding  46 , canal extension  48 , and IROS cut  50 .  FIG. 14A  illustrates a shell without an IROS cut, and  FIG. 14B  illustrates a shell with an IROS cut. The IROS cut creates a steplike structure on the shell tip. This is used, e.g., to create an impression at the customer site in which the vent inlet on the tip side is bigger than it is in reality. This cut also provides certain audiological advantages. The augmented detailing protocols may further include the Prahl taper  52 , helix taper  54 , and scoop  56 . A more detailed explanation of these procedures may be found in the pending patent application listed in the opening paragraph of this application. 
         [0040]    A shell options module  60  allows the user to configure a number of parameters associated with the shell and store them. A further module, the component placement protocols module  70 , assists in placing the components and ensuring that collisions do not take place. Finally, a faceplate integration module  80  is provided in order to assist in the proper placement of faceplates. Data from the completed design is the stored in a database  90  that includes the finalized shell information. 
         [0041]    The procedure defines the automatic protocols for automation of modeling, detailing and component placement of ITE shells, including the following categories described in more detail below: a) general rules; detailing rules for b) ITE, c) HS, d) CA, e) MC, f) CIC designs; g) rules for the receiver hole and vent; h) rules for component placement; and i) rules for collision detection. 
       A) General Rule-Based Requirements 
       [0042]    Software modules on the system detect, extract, and measures all essential features that are required for primary cuts, and listed in  FIG. 2 . Impressions are detailed based on the prescribed device type, and the appertaining rules for modeling each device type are defined in the following sections. The software combines line cuts with associated cosmetic detailing protocols, and it performs canal extension, tapering and rounding based on prescribed preferences parameters for device type. The aperture of the impression can be used as the initial starting point for extension, tapering and rounding. 
         [0043]    The software places components into the shell based on rules associated with device type. In CICs, MC, and CA types, an insert module is placed such that the battery door is below the aperture line. All receivers are placed as close as possible to the canal tip, and the shell height can be reduced based on where a collision occurs between the electronic components associated with the faceplate, receiver suspension, and floating hybrid components. 
         [0044]    The placements of components is based on recognized device features and business logic. A specific orientation exists for faceplate placement. For instance, in full shells, faceplate orientation is such that the battery door opens towards the tragus. Secondly, identified landmarks on the shell indicate the preliminary height of the device. Referring to  FIGS. 19A and 19B , in an embodiment, the impression is oriented so that the helix, concha, and canal openings are at a consistent height and parallel to the base of the impression—a plane is defined through the base of the impression. Ideally, the plane cuts the impression approximately 2 mm down from the center of the flares of the tragus, anti-tragus, and helix towards the base of the impression. When real estate is still available in the shell based on collision verification, the software lowers the shell further. 
         [0045]    Collision verification, avoidance, and final assembly are based on sequentially defined rules: all detailing cuts can be executed automatically by the software; components are placed such that there is a minimum distance (“Minimum Distance Configurable”) between components; and components can be lowered further towards the canal end of the shell (along the centerline) if there is more real estate after the preliminary component placement. 
         [0046]    The system software has the ability to dynamically load and execute device based rules. Routines for modeling device types can be loaded as part of an Instrument Model Options in DWOM, and the software can display the device type being modeled using DWOM protocols. 
         [0047]    The system software can dynamically place electronic components based on assigned rules for the device type. The initial receiver placement is below the aperture and above the canal tips, and the location of the receiver in each device type is configurable. The faceplate placement and orientation are configurable per device type, and the placement takes into account unique device features. The faceplate orientation per device and the maximum allowable shell height are configurable as well. The software is able to place vent and receiver holes based on device types, and the faceplate placement and merge are based on pre-defined rules for the device type. 
         [0048]    All line cuts and corresponding features required to rule detail impressions are shown in  FIG. 2 . The system allows the user to make minor angle adjustments for primary and cosmetic cuts, but in an embodiment of the invention, there is no user intervention required. Accordingly,  FIG. 2  shows the cutting-detailing operations  100  and the corresponding features  102  required to accomplish an appertaining cutting-detailing operation  100 . 
         [0049]    The initial line cut  100 . 1  requires information pertaining to the anti-tragus center, tragus center, and anti helix  102 . 1 . The intertragal nix cut round  100 . 2  requires information pertaining to the intertragal notch and the shell side  102 . 2 . The crus cut round plane  100 . 3  requires information related to the crus, curs valley, and shell side  102 . 3 . The low angular cut plane  100 . 4  requires information related to the intertragal notch, and the peak of the concha curvature  102 . 4 . The reduct to device cut  100 . 5  requires information about material above the hollowed end of the device  103 . 5 . 
         [0050]    Canal tapering  100 . 6  requires information about the canal and the aperture. A tapering of canals 8 mm or longer is performed on ST, HS, and CA models only (i.e., more than 8 mm from the low of the aperture to the cut line on the canal). A tapering of canals shorter than 8 mm (ST, HS, and CA, i.e., less than 8 mm from the lower of the aperture to the cut line on the canal) makes use of an extended taper. The canal width after the taper is applied should be no more than approximately 2 mm larger than the narrowest area of the aperture. 
         [0051]    The helix reduction  100 . 8  requires information about the helix and the helix ring. The crus scooping  100 . 8  requires information pertaining to the crus. The artifact removal  100 . 9  requires information about bulbous regions, voids, and depression  102 . 9 . Finally, the canal extension  100 . 10  requires information about the canal length and bends  102 . 10 . In a preferred embodiment, the maximum allowed extension is 2 mm. To achieve this, a plane is defined on the canal tip perpendicular to the direction of required extension, and the extension is performed, with a test to ensure that the canal does not extend at an incorrect angle based on the first and second bend areas. This list covers the primary cuts, but is in no way exhaustive as to the information that can be associated with other cuts as well. 
       B) Detailing Rules for Full Shell (ITE) 
       [0052]    As illustrated in  FIG. 3 , and according to the detailing rules for a full shell ITE device, the system software inserts an initial cutting contour  310  ( 100 . 1 ) at the center of the tragus (not shown), the center of the anti-tragus (not shown), and the anti-helix  426 . As is illustrated by  FIG. 3 , where the transparent region is removed by this cut operation; this is a standard cut for ail devices. The software automatically removes all material below the hollowed end of the shell  410 , and recognizes and removes the lower end of the intertragal notch  440  ( 100 . 2 ), as illustrated by  FIG. 4 ; this is usually removed to reduce painful insertion for the patient. The degree of rounding of the intertragal notch can be configurable. 
         [0053]    The system software automatically trims the canal using the following criteria: the canal length is determined from the aperture to the canal tip, and the canal length is configurable for, e.g., “Small,” “Medium” (default) and “Large”. The software can taper the canal based on, e.g., “Long”, “Medium”, and Short. The following table illustrates configurations in a preferred embodiment of the invention. 
         [0000]    
       
         
               
             
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Configuration Table with Values 
               
             
          
           
               
                   
                 Parameter Name 
                 Strength 
                 Value 
               
               
                   
                   
               
             
          
           
               
                   
                 Tapering 
                 Small 
                 0.06 
               
               
                   
                   
                 Medium 
                 0.08 
               
               
                   
                   
                 Large 
                 0.10 
               
               
                   
                 Canal Length 
                 Small 
                 0.1 
               
               
                   
                   
                 Medium 
                 0.2 
               
               
                   
                   
                 Large 
                 0.3 
               
               
                   
                 Rounding 
                 Small 
                 0.06 
               
               
                   
                   
                 Medium 
                 0.08 
               
               
                   
                   
                 Large 
                 0.10 
               
               
                   
                 Prahl Tapering 
                 Small 
                 1 
               
               
                   
                   
                 Medium 
                 2 
               
               
                   
                 Helix Tapering 
                 Small 
                 1 
               
               
                   
                   
                 Medium 
                 2 
               
               
                   
                   
               
             
          
         
       
     
         [0054]      FIG. 18  illustrates an alternative for canal cutting, in which a canal length is specified either by market specific requirements or by a customer specified length. As illustrated, the cut can be made just after the first bend (SH), between the first and second bend (MD), at the second bend (LN), and after the second bend (DP). If a bell bore is selected, then in an embodiment, the canal is cut 2 mm longer than the specified line cut. CIC models should generally always be cut 2-4 mm past the second bend. For all canal cutting, the system should ensure a binaural match for: the canal length, the canal tip shape, and the canal cut plane (i.e., the resulting canal tip shape should be similar on both sides). 
         [0055]    The system software can automatically extend the canal according to the following criteria: the canal length is determined from the aperture to the canal tip, and may be configurable for, e.g., “Small”, “Medium” (default), and “Large”. The software can taper the canal based on, e.g., three configurable levels: “Long”, “Medium”, and “Short”. The tapering starts from the aperture and the optimum direction is normal to the centerline plane at the second bend. Using a buildability index computation algorithm  36 , the software can determine whether a canal extension or tapering is required. 
         [0056]    The system software detects and reduces the helix length ( 100 . 7 ), which is configurable as, e.g., “Medium”, “Small”, and “Remove”. The software can provide two additional options or attributes to determine whether the helix should be preserved or not: “Preserve Helix” and “Remove Helix”. Faceplate lowering can be used to optimize and finalize the shell height. The requirements on rule based component placement are defined in subsequent sections. 
       C) Detailing Rules for Half Shell (HS) 
       [0057]    The basic steps for modeling HS shells are shown in  FIG. 6 . According to he detailing rules for a half shell HS device, the requirements are as follows. Referring to  FIGS. 6 and 7 , the system software can identify and remove the concha of the impression (Reduct_to_Device_Cut  100 . 5 ) by inserting a cutting plane  310  along the crus; the crus can be eliminated using a configured level of a Rounding—Crus_Cut_Round_Plane. 
         [0058]    The software can measure the distance from the center of the tragus to the concha. The minimum dimension for a half-shell measure from the tragus to the concha can be configurable as a shell width; all material beyond the shell width is preferably removed with a configured rounding 
         [0059]    A Low_Angular_Cut ( 100 . 4 ) can be inserted at a configurable angle (the “cut angle”) from the inter-tragal notch to intersect a perpendicular line from the concha peak to the angular plane; the optimal shell height from the concha peak to the angle plane can be configurable as the concha height. 
       D) Detailing Rules for Canal (CA) 
       [0060]    According to he detailing rules for a canal CA device, the system software identifies all the features required to detail a canal (shown in  FIG. 2 ). The software recognizes and removes the concha of an impression by inserting the cutting plane along the crus using a configured level of rounding—the Crus_Cut_Round_Plane  100 . 3 , which is shown in  FIG. 7 . The software measures the distance from the center of the tragus to the mid-concha curvature. The minimum dimension for a canal is configurable as the shell width (specified in, e.g., mm); all material behind the shell width  442  is removed with a configurable level of rounding. If the measured distance is less than the shell width, the software can display an error message, such as, “Insufficient materials; specified device type cannot be built.” 
         [0061]    A Low_Angular_Cut  100 . 4  can be initiated at the inter-tragal notch and the concha curvature peak; the angular value can be configurable in the preferences table for each device type. The optimal shell height from the concha peak to the angle plane can be configurable as the concha height.  FIG. 8  illustrates the Low_Angular_Cuts_Plane  100 . 4  and the shell Reduce_to_Device_Cut  100 . 5 . 
       E) Detailing Rules for Mini Canal (MC) 
       [0062]    According to the detailing rules for a mini-canal MC device, the system software identifies and removes the concha of the impression by inserting a cutting plane along the crus—the Crus_Cut_Round_Plane  100 . 3 , with the level of rounding being configurable, as is illustrated in  FIG. 7 . The software measures the distance from the center of the tragus to the concha, and the minimum dimension for a mini-canal can be configurable as the shell width. All material behind the configured shell width  442  may be removed with a configured rounding. A Low_Angular_Cut  100 . 3  can be inserted at a configured angle (the cut angle) from the inter-tragal notch and the concha curvature peak. The optimal shell height from the concha peak to the angle plane can be configurable as the concha height. 
         [0063]    All electronic components are placed based on the device rules: the faceplate is placed on the resulting impression from the rule based cuts; the faceplate is lowered until a collision occurs with the internal components or the shell, and the faceplate plane can be used to finalize the shell lowering. The receiver is placed close to the canal and below the aperture; the distance from the tip should be configurable as well. This is discussed in more detail below. 
       F) Completely-In-The-Canal (CIC) 
       [0064]    Referring to  FIG. 9 , according to the detailing rules for a completely-in-the-canal CIC device, the CIC requirements can be implemented using the following approaches for the low angular cut plane  100 . 4 , the aperture plane is oriented at a configured angle (cut angle) to the centerline direction; all material below the aperture is removed. The canal length from the aperture to the canal tip is configured as the shell height, and the canal is extended along the centerline by a configurable value (the canal extension  100 . 10 ). If the canal is longer than the configurable values, it is automatically trimmed and tapered by a configurable value (the canal tapering  100 . 6 ). 
         [0065]    A receiver is placed at a configured distance from the canal tip, and the faceplate is placed and lowered with collision verification of the electronics module with the shell and other components (discussed below). 
       G) Rules on Receiver and Vent Holes 
       [0066]      FIG. 10  illustrates a receiver hole  421  and vent configuration  416  on an elliptical canal tip. The software determines that, for CIC and ITE designs, the vent  416  and receiver channel  421  configurations are fixed as shown. In CIC and ITE designs, all vents follow a defined contour from the canal tip along the intertragal notch. The receiver hole  421  is drilled along the crus side of the canal, with the receiver  421  and vent channels  416  being equidistant from the sides of the impression canal and centered at the foci of the canal ellipse. (See  FIG. 10  (A-B)) 
         [0067]    However, the software determines that, for HS, CA, and MC designs, the vent  416  and receiver  421  channel configurations are interchanged (i.e., are the reverse of what is shown in  FIG. 10 ). For directional shells, the software determines that the receiver  421  and vent  416  configuration are the same as that for CIC and ITE designs. (See  FIG. 10 ). 
         [0068]    These rules have certain exceptions: when a venting channel  416  is not explicitly specified, the receiver channel  421  is placed at the center of the canal, and for GIC designs, the vent is re-oriented when there is insufficient real estate. 
         [0069]    Various shell options can also be implemented. For example, the shell wall thickness can have various configurable options. An option for a variable wall thickness is provided, for example, the system may provide for an adaptive wall thickness in high curvature regions. Variable thickness may be defined as a percent increase of the uniform wall thickness specification in a user configurable preferences database which may, e.g., be accessed via a displayed tab. Alternative variable thickness algorithms can be implemented with a polynomial function. However, the software can provide an option for specifying a uniform wall thickness (a default wall thickness). Furthermore, the software can provide an option for the application of selective wall thickness to a specified area of the shell-this region may be selectable by the user who may use, e.g., a lasso selection tool as is known in the graphical arts. A further capability of the software may be allowing empty areas of the shell to be filled with material. 
         [0070]    The software is designed to place the receiver hole on the correct side of the impression (left or right) using feature recognition (FR) protocols which identify different pre-defined areas of the shell such as helix, tragus, aperture etc. FR also can identify the canal and tip of the impression. By knowing the location of the tip of the impression, the software can automatically position the receiver hole on the left or on the right side of the tip, depending on the instructions for the specific shell type 
         [0071]    With regard to vent generation, the software is designed to define vent location and orientation, and to allow control of the vent placement and the specification of the location of vents based on a particular device type. The software ensures the placement of vents based on whether an impression is identified as left and right ear impression. Furthermore, the software may provide an enable/disable function, via, e.g., check boxes of the user interface, in a user interface area associated with vent options (e.g., a vent tab under a preferences area), as well as in a user interface area in the “modeling” flow step for simulation vent placement. When the vent feature is enabled, a virtual vent is shown to the user in the user interface. The vent simulation considers the available space in the shell , and the vent generation takes into consideration the presence of components and possible interaction with components. In a preferred embodiment, a collision between vents and shell components may be highlighted—the software thus allows collision detection with components to take into account the presence of the vent. The user can change the vent type based on a prior database configuration, and modified vent types and options can be written to the database DB. The system allows the selection of both vent type and styles. 
         [0072]    Furthermore, the vent wall thickness can be configurable for all device types, and the level of component penetration of electronic components into the vent wall is configurable as, e.g., a numerical value; this configuration parameter can be associated with the other vent configuration parameters and presented to the user under, e.g., the displayed vent tab. Additionally, the collision display for the colliding triangles can be configured in a different color (e.g., via a user display color tab). 
       H) Dynamic Component Placement 
       [0073]    The software ensures that colliding components are placed at a configurable distance from nearest neighbors-this is essentially a self-correcting interference mechanism for collision. Colliding components within the shell shall have the ability to self-align to offset collision, and a feedback mechanism allows device size optimization. 
         [0074]    Electronic components can be lowered further into the shell as long as the resulting contact forces in a z-direction do not exceed a configurable maximum normal force value (see  FIG. 11 , illustrating reactional forces resulting from component interaction within the shell). The allowable maximum normal force can be configurable as a parameter MAX-Normal-Force in the user-configurable preferences. 
         [0075]    Receiver Placement 
         [0076]    The software can automatically place the receiver at the canal tip, in accordance with the following criteria. The receiver snout is positioned from the canal tip on a configurable canal-receiver snout distance. The top of the receiver is placed such that its width is aligned to a major axis of the nearest shell ellipse. The center of the ellipse is at the center of the receiver geometry, and the receiver is placed below the aperture line. However, if the receiver does not fit below the aperture, it is then positioned as low as possible. Double receivers are usually too large to fit into the canal, and thus these are usually allowed to sit above the aperture. Collsion detection is ideally enabled for all geometric component and new surfaces created, e.g. integrated faceplate surfaces, gluing surfaces, and suspensions. 
         [0077]    Automatic Faceplate Placement and Integration 
         [0078]      FIGS. 12A-F  illustrate faceplate orientation according to different shell types.  FIGS. 12A and 12B  illustrate a full shell (FS) design.  FIGS. 12C and 12D  illustrate half shell (HS), canal (CA), and mini-canal (MC) designs. Finally,  FIGS. 12E and 12F  illustrate a completelyin-canal (CIC) design. Each of the figures illustrate the location of various features of the hearing aid shell  10  (note that reference characters are prime in  FIGS. 12C and 12D , and double-prime in FIGS.  12 E and  12 F—use of the reference character without the corresponding prime marks is intended to be inclusive where appropriate). Accordingly, the features of the helix  412 , anti-tragus  414 , vent  416 , tragus  418 , microphone  420 , crus  422 , and concha bowl  424  can be seen. 
         [0079]    Battery Door Placement 
         [0080]    For an in-the-ear (ITE) device, the battery door ( FIG. 13 ) is positioned such that it opens away from the tragus  418 . But for HS, CA and MC designs, the battery door is positioned such that it opens towards the tragus  418 . In the CIC design, the battery door is positioned so that it opens away from the vent hole  416 . 
       I) Collision Detection 
       [0081]    The software is designed to ensure that collision detection is facilitated between the merge surfaces and the components according to the following algorithm: 
         [0082]    1) Surface triangles are extracted to form a separate Stereolithography Tessellation Language (STL) file that represents a merge surface of the shell. 
         [0083]    2) Every part of the merge surface STL and each component is compared as to whether they intersect. 
         [0084]    3) If any of the components and merge surface STL intersect, then a collision is reported ( FIG. 15A ). Otherwise no collision is reported ( FIG. 15B ). 
         [0085]    This may be achieved with the user of a display to the user and related processing software, as illustrated in  FIGS. 15A , B. These Figures illustrate the shell which is clipped by the clipping plane to see the inside of the shell. In  FIG. 15A , the receiver collides with the shell, and the receiver may. e.g., be shown in red and the area where collision happens in yellow. On  FIG. 15B , no collision occurs and faceplate may, e.g., be drawn in green. This permits rapid feedback to the user of the system. 
         [0086]    The software detects and may display all colliding triangles based on, e.g., a configurable color in a preferences table that can be modified by a user (or any other graphical tool that could serve to highlight a collision. This collision detection is enabled between:
       the shell and all internal and external interacting components;   the faceplate/faceplate options and a virtual cast (VC) (the virtual cast is the original undetailed impression which represents the reference point to the human ear during modeling and detailing. Technicians often check during their modeling and detailing work to see how the shell “sits” in the virtual cast. If for any reason the faceplate or faceplate options collide with the virtual cast, this means that in real life, the faceplate or the faceplate options will hurt the ear of the patient because of protrusions and discontinuities. A display of a the shell sitting within the virtual cast can be seen in  FIG. 16 ;   optional components, such as a push button PB ( FIG. 17A ) or a volume control VCtl ( FIG. 17B ); and   the faceplate.       
 
         [0091]    For each of these three, a user-interface element, such as a check box, can enable and disable collision detection, but, in a preferred embodiment, the default value for detection would be “true”. In order to facilitate operation, all of the electrical components can have a configurable color to make them easy to visualize by the user. 
         [0092]    For the purposes of promoting an understanding of the principles of the invention, reference has been made to the preferred embodiments illustrated in the drawings, and specific language has been used to describe these embodiments. However, no limitation of the scope of the invention is intended by this specific language, and the invention should be construed to encompass all embodiments that would normally occur to one of ordinary skill in the art. 
         [0093]    The present invention may be described in terms of functional block components and various processing steps. Such functional blocks may be realized by any number of hardware and/or software components configured to perform the specified functions. For example, the present invention may employ various integrated circuit components, e.g., memory elements, processing elements, logic elements, look-up tables, and the like, which may carry out a variety of functions under the control of one or more microprocessors or other control devices. Similarly, where the elements of the present invention are implemented using software programming or software elements the invention may be implemented with any programming or scripting language such as C, C++, Java, assembler, or the like, with the various algorithms being implemented with any combination of data structures, objects, processes, routines or other programming elements. Furthermore, the present invention could employ any number of conventional techniques for electronics configuration, signal processing and/or control, data processing and the like. 
         [0094]    The particular implementations shown and described herein are illustrative examples of the invention and are not intended to otherwise limit the scope of the invention in any way. For the sake of brevity, conventional electronics, control systems, software development and other functional aspects of the systems (and components of the individual operating components of the systems) may not be described in detail. Furthermore, the connecting lines, or connectors shown in the various figures presented are intended to represent exemplary functional relationships and/or physical or logical couplings between the various elements. It should be noted that many alternative or additional functional relationships, physical connections or logical connections may be present in a practical device. Moreover, no item or component is essential to the practice of the invention unless the element is specifically described as “essential” or “critical”. Numerous modifications and adaptations will be readily apparent to those skilled in this art without departing from the spirit and scope of the present invention. 
       TABLE OF REFERENCE CHARACTERS [TO BE COMPLETED IN NEXT DRAFT] 
       [0095]      
         [0000]    
       
         
               
               
             
           
               
                   
               
             
             
               
                 10 
                 system 
               
               
                 12 
                 digital work order management DWOM 
               
               
                 20 
                 tessellation module 
               
               
                 30 
                 analysis procedure 
               
               
                 32 
                 feature recognition 
               
               
                 34 
                 registration of features 
               
               
                 36 
                 buildability index computation BIA 
               
               
                 38 
                 rule-based protocol handling 38 
               
               
                 40 
                 global and local offset module 
               
               
                 42 
                 binaural processing 
               
               
                 44 
                 tapering 
               
               
                 46 
                 rounding 46 
               
               
                 48 
                 canal extension 
               
               
                 50 
                 IROS cut 
               
               
                 52 
                 Prahl taper 
               
               
                 54 
                 helix taper 
               
               
                 56 
                 scoop 
               
               
                 60 
                 shell options module 
               
               
                 70 
                 component placement protocols module 
               
               
                 80 
                 faceplate integration module 
               
               
                 90 
                 database 
               
               
                 100, 
                 cutting-detailing operations 
               
               
                 100.1-10 
               
               
                 102, 
                 features required to accomplish operation 
               
               
                 102.1-10 
               
               
                 310  
                 initial cutting contour 
               
               
                 312  
                 plane 
               
               
                 410  
                 hearing aid shells 
               
               
                 412  
                 helix 
               
               
                 414  
                 anti-tragus 
               
               
                 416  
                 vent 
               
               
                 418  
                 tragus 
               
               
                 420  
                 microphone 
               
               
                 421  
                 receiver (channel) 
               
               
                 422  
                 crus 
               
               
                 424  
                 concha bowl 
               
               
                 426  
                 anti-helix 
               
               
                 440  
                 lower end of intertragal notch 
               
               
                 442  
                 shell material to be removed