Patent Publication Number: US-2023138070-A1

Title: Method and Apparatus to Generate Measurements for and Manufacture a Conformal Fitting Cap

Description:
BACKGROUND 
     Sizes of human heads generally vary by gender and age with males have nominally larger heads than females, and adults having larger heads than children. Within each grouping, moreover, there is a large distribution in size—one size does not fit all. One&#39;s head circumference is generally accepted as a metric of head size but anthropometric head survey data indicates the circumference of adult heads ranges from 50 to 63 centimeters and the unique shape of each human head cannot be discerned by circumference alone. Thus, many other measurements along other dimensions define one&#39;s head size and shape. 
     Head gear matching a particular head size and shape is important for medical applications especially when the head gear incorporates instrumentation, thermal control, or stabilization. Even a small mismatch may degrade the functional effectiveness of the head gear. These applications include treating brain trauma, treating alopecia induced by chemotherapy, immobilizing the head during and/or after surgery, suppressing the effects of concussion, and other uses. Non-medical applications include head gear for electroencephalograms (EEG) or other brain activity sensors, such as those that may interpret sleep activity or intent of the wearer for controlling external devices, e.g., automobiles, electronic games, or virtual reality simulators, etc. When used medically, it may be preferable that conformal head gear be immediately available or very shortly after the need for it arises in order for the medical treatment is to be effective. For example, to cool the scalp for treating alopecia induced by chemotherapy, the patient may have only a few days from cancer diagnosis until treatment. During that time, the patient may need to accept the diagnosis, research treatments, make decisions, and order and receive a cooling cap, all of which can be stressful. For brain trauma and depending on its severity, the patient may be discharged within days of the injury with a portable hypothermia device with a cooling cap for on-going treatments, such as described in U.S. Pat. No. 10,806,626 B2 issued 20 Oct. 2020 entitled Method and Apparatus of a Self-Managed Portable Hypothermia System to Zumbrunnen et al. and U.S. patent application Ser. No. 17/019,301 filed 13 Sep. 2020, U.S. Patent Application Publication No. US 202110022915 A1, published 28 Jan. 2021 entitled Method and Apparatus of a Self-Managed Portable Hypothermia System to Zumbrunnen et al., all of which are herein incorporated by reference in their entirely. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 A and  1 B  are depictions of apparati that may be used to scan a person&#39;s head. 
         FIG.  1 C  represents the scanned measurement data. 
         FIG.  2    describes a method to obtain scanned measurement data of a person&#39;s head. 
         FIG.  3    is a view of a processing system in communication with a transformable tool and a 3-D printer by which a conformal cap can be manufactured. 
         FIG.  4    describes a method to transform the scanned measurement data to a useable format. 
         FIG.  5    illustrates the isometric illustration of transformed data set. 
         FIGS.  6  and  7    are a plan view and an isometric view, respectively, of the transformable too. 
         FIG.  8 A  is an enlarged view of a perimeter actuators.  FIG.  8 B  is an enlarged view an interior actuator. 
         FIG.  9    is an enlarged isometric view of the perimeter actuators and interior actuators of the transformable mold. 
         FIG.  10    describes a method to set up a transformable tool and manufacture a conformable cap. 
         FIG.  11    illustrates a fabric cap placed over a transformable mold. 
         FIG.  12    illustrates an embodiment of a conformal cap wrapped in tubing. 
         FIG.  13    illustrates an embodiment of applying foam to make a conformal cap with the transformable mold 
     
    
    
     The preceding FIGS. are best viewed in conjunction with the following description. 
     SPECIFICATION 
     In accordance with the disclosure herein,  FIG.  1 A  illustrates a person&#39;s head  100 . An expandable yet tight-fitting material  110  is placed on the person&#39;s head  100 . Preferably, the expandable tight-fitting material  110  may be thin rubber, silicone, or other biocompatible material. The person&#39;s hair  120  is compressed against the skull and trapped in as thin a layer as possible between the skull and the expandable tight-fitting material  110 . Given the variability of head sizes possible, the expandable tight-fitting material  110  may be stretched in different tensions and different dimensions for each individual in order to cover all or part of the ears and forehead once snugly situated, this step is shown as block  210  in  FIG.  2   . To distinguish where the end (beginning) of the custom to-be-made conformal cap should be situated relative to other head features such as forehead, eyes, ears, etc., an O-ring  130  stretchable from 400 to 800 centimeters in diameter is situated over the expandable tight-fitting material  110  at a location where the end (beginning) of the conformal to-be-made cap is desired, as indicated as block  220  of  FIG.  2   . The expandable tight-fitting material  110 , once snugly situated on the person&#39;s head  100 , represents the interior surface of the to-be-made custom cap. It is preferable that O-ring  130  be of a different color, texture, or otherwise distinctive than the expandable tight-fitting material  110  so that it can be distinguished easily, as will be described herein. 
     An activated scanning device  150  is orbited 360 degrees around the person&#39;s head  100  as indicated by arrows  160 . The scanning device  150  captures scanned measurement data  190  of approximately 30,000 x, y, z data points, as shown in  FIG.  1 C , representing the physical coordinates of the outside surface of the person&#39;s head  100 . 
     Alternatively, as illustrated in  FIG.  1 B , the scanner  150  can be stationary  190  and the person, donned with the expandable material  110  and the O-ring  130  can rotate 360 degrees within the aperture of the scanning device  150 , as indicated by arrows  160 . In either case, a complete scanned measurement data  190  representing the surface of a person&#39;s head  100  is captured by the scanning device  150  in block  230 . The scanning device  150  preferably is accurate to one millimeter or less, and is able to discern variations in color, texture or other contrasts. The scanning device  150  may be a hand-held mobile device having a light detection and ranging (LIDAR) sensor, a camera, a laser scanning sensor, or a sensitive smart phone camera such as an iPhone TrueDepth™ camera. 
     With reference to  FIG.  1 A , the direction from the O-ring  130  towards the crown  170  of the head  100  will be deemed to be up or above. The direction from O-ring  130  towards the chin  180  and shoulder will be deemed to be down or below. The direction from the expandable material  110  and O-ring  130  towards the interior of the person&#39;s head  100  will be deemed to be inside, inner, or interior. The direction from the expandable material  110  and O-ring  130  away from the person&#39;s head  110  will be deemed to be outside, outer, or exterior. 
     The scanned measurement data  190  are exported from the scanning device  150  in OBJ, PLY, JPEG or similar industry standard file format capable of translating to x, y, z coordinates for additional processing, as in block  240  of  FIG.  2   . The ability to ascertain contrast variability allows discernment of data points corresponding to the position of the O-ring  130  relative to the entire scanned measurement data. Under ideal circumstances with a cooperative person and an experienced other person operating the scanner, the entire process may require five minutes or less which may involve donning the expandable material  110  on the person&#39;s head  100 , situating the O-ring  130 , obtaining the scanned measurement data  190  representing the coordinates of the expandable material  110  on the person&#39;s head  100 , and transmitting the scanned measurement data  190  for subsequent analysis. 
     As mentioned and shown in block  240  of  FIG.  2   , the tens of thousands data points of the scanned measurement data  190  shown in  FIG.  1 C  correlate to the x, y, z physical coordinates of the expandable material  110  on the person&#39;s head  100 . The scanned measurement data  190  are transmitted to a processor system  300  to be processed by a mesh manipulation module  310 , as shown in  FIG.  3   . The mesh manipulation module  310  may be stored in a memory  320  associated with the processor system  300  or may be downloaded into the processor system  300  from a remote server  340  or may be embodied as firmware within or connected to processor system  300 . It is further within the purview of this description that the mesh manipulation module  310  may be executing in a processing system  300  within the scanning device  150  itself or may be transmitted to a remote processing system  340 . It is further considered herein that processing system  300  may be contained with the transformable mold tool  620  and/or a 3-D printer. It is further within the purview of this description that the scanned measurement data  190  may be transmitted to processing system  300  via wired  360  or wireless  370  connections. 
     Viewing  FIGS.  4  and  5    together, in block  410 , the scanned measurement data  190  is input into the processing system  300  executing a mesh manipulation module  310 . In block  420 , the mesh manipulation module  310  determines which data points of the scanned measurement data  190  correspond to the location of the O-ring  130  because of its contrasting color, texture, or other distinguishing attribute. Using the location of the circumscribed O-ring  130 , step  430  creates a plane  510  having x-y axes coincident with the plane of the O-ring  130 . In step  440 , the mesh manipulation module  310  determines a major axis  530  and a minor axis  540  on the x-y plane  510  of an elliptical-like shape determined by the scanned measurement data  190  inside the O-ring  130 . Point  550  is the intersection of the x- and y-axes and will be considered x′ and y′. One of skill in the art will appreciate that the scanned measurement data  190  of the O-ring  130  will not be a perfect ellipse because of variations of the individual heads. In step  450 , at the intersection of the major axis  530  and the minor axis  540 , a z-axis  560  and its origin z′ are determined so that the z-axis  560  extends orthogonally from the x-y plane  510  up towards the crown  170  of the person&#39;s head  100  to create a surface  570  bounded by the scanned measurement data  190  above the O-ring  130 . In step  460 , the scanned measurement data  190  below the x-y plane  510  and outside or exterior to the O-ring  130  are removed from the measurement data and are not involved in the further processing. In step  470 , the retained scanned measurement data  190  are transformed to orient the surface  570  consistent with a physical tool implementation (described below) such that the transformed measurement data  570  has an origin  550 , i.e., x″, y″, z″, located in x and y directions on the x-y plane  510  extending upward along a z-axis  560 . 
     The transformed measurement data  570  describes the inside surface of a conformal cap corresponding to the outside surface of a person&#39;s head  100 . The transformed measurement data  570  is input into a conformal cap design module located in processor system  300  for creating additional conformal cap features beyond the inside surface of the conformal cap. The transformed measurement data  570  and the additional conformal cap design features are transmitted to a transformable tool  620  or to a 3-D printing tool  610  for conformal cap fabrication. 
     With reference to  FIGS.  3 ,  6 ,  7 , and  8   , the transformed measurement data  570  is input into a transformable tool  620  comprising a transformable mold  630 . Transformable mold  630  comprises a plurality of actuators  710  and actuator assemblies  810 , both of which can be articulated independently as described herein to create a surrogate head form matching in size and shape to the transformed measurement data. 
       FIGS.  8 A and  8 B  illustrate the structure of the actuator assemblies  810  and actuators  710 . Shown in  FIG.  8 A , actuator assemblies  810  comprise a first perimeter actuator  820  and a second perimeter actuator  830 . First perimeter actuator  820  comprises a horizontal solenoid/cylinder  890  for x- or y-directional movement depending on its location within the transformable mold  630 . A second perimeter actuator  830  comprises a vertical solenoid/cylinder  880  for z-directional movement. The perimeter actuator assemblies  810  define the lowest perimeter of the cap to be made at location set by O-ring  130  in the x-y plane  510 . The perimeter actuator assemblies  810  comprise base  840 , a post  850  rising from the base, rod  860 , power and control connections  895 , and mechanical hardware  885  to structurally maintain the actuators  820 ,  830 . The base  840  is flat or contoured at location z″  855  to capture the first (last) conduit of the cap that may be placed between post  850  and rod  860 . Cylinder  880  is located as close to post  850  as the implementing cylinder technology will allow. Close proximity between cylinder  880  and post  850  is important because the head size typically changes size rapidly away from the z-plane at the perimeter location. Rod  860  emanates from the z″ location as perimeter actuator  830  extends or retracts cylinder  880  at location  870 . 
       FIG.  8 B  shows the structure of interior actuator  710  comprising a movable cylinder  720  from which a portion is of smaller diameter  730 , preferably two millimeters or less at tip  740 . Rod  720  extends along the z-direction to define the height of the interior dimensions of the conformal cap to be manufactured. Tips  870  of actuator assemblies  810  and tips  740  of actuator  710  are smooth and rounded to prevent damage to the soon-to-be formed cap resting on top 
       FIG.  6    shows a plan view of the transformable tool  620 . Ideally, a single transformable tool  620  accommodates the smallest to the largest head sizes as documented in anatomical databases. The number of actuators  710  and actuator assemblies  810  is determined by the desired accuracy of the surrogate head but may be also limited by the physical size of the actuators  710 ,  820 ,  830  within the transformable tool  620 . Thus, the relative position of the actuators  710 ,  820 ,  830  to each other are determined by the transformable tool&#39;s  620  physical implementation. In one embodiment, the transformable tool  620  may have up to three hundred actuators  710 ,  820 ,  830  to set the x-y-z locations of the transformable mold  630 . The minimum actuator periodicity, based on current commercially available state-of-the-art actuators, is eighteen millimeters, but this dimension is not intended to be limiting. Pneumatic, electrical, mechanical, and even piezoelectric movement actuators on the order of micrometers or even nanometers are to be considered within the purview of this disclosure. In one embodiment with regard to physical constraints and desired accuracy, the transformable mold  630  has two hundred three (203) actuators  710 ,  820 ,  830  of which ninety-nine are interior actuators  710  and are fixed in an array  650  with its center at x′, y′, z′. The perimeter actuator assemblies  810  are distributed around the perimeter of the transformable tool  620  with a portion indicated as  820  dedicated to x- and y-movement, and a portion indicated as  830  allocated to movement along the z-direction. In one example of specific transformed data but not to be limiting, fifty-two perimeter actuator assemblies  810  defines the location set by O-ring  130  in the x-y plane  510  on the transformable mold  630 . Each actuator assembly  810  is located within transformable tool  620  by fastening actuator  830  using mounting hole  825  to a fixed location within tool (not shown) and retaining the bottom surface  845  of base  840  as channels located in surface  625   
     Ideally, a single tool  620  accommodates the smallest to the largest head sizes as documented in anatomical databases. Depending on head size, some interior actuators  710  and some perimeter actuator assemblies  810  will not be used because they are outside the perimeter of the transformed measurement data  570 . For example, for a medium head size, actuators in the areas  660  are moved to a position away from use so as to not interfere with other actuators in the final transformable mold  630 .  FIG.  7    illustrates an embodiment of the transformable tool  620  with more detail of the transformable mold  630  having a plurality of perimeter actuator assemblies  810  and an array of interior actuators  710  at locations extending above the x-y plane  510  to correspond to the transformed measurement data  570  or at retracted locations  660 . 
       FIG.  9    is an enlargement of the region indicated in  FIG.  7    and illustrates rods  860  extending beyond base  840  to tip  870  for multiple perimeter actuator assemblies  810 . Each show their tip  870  located to a z-height to match the transformed data at that location. Once the perimeter actuator assemblies  810  and interior actuators  710  have their cylinders moved to their appropriate locations, cylinder tips  870  of actuator  830  and tips  740  of actuators  710  are extended to represent points on a surrogate head of the original head size and shape. 
       FIG.  10    represents the method by which to manipulate the actuators  710 ,  820 ,  830  in the transformable mold  630  to achieve a mold for manufacturing a conformal cap. In block  1001 , prior to executing a transformation, cylinders  720 ,  880 ,  890  are fully retracted in actuators  710 ,  830 ,  820  respectively and the actuators are deactivated. In block  1005 , the transformed measurement data  570  from block  470  of  FIG.  4    is input to a transformation module  350 . Transformation module  350  may be embedded as firmware in the transformation tool  620 , 3-D printer  610 , or stored and executing in a local or remote processing system  300 ,  340  in communication with the transformation tool  620  or a 3-D printer  610 . 
     In block  1010 , the transformation module  350  determines the coordinates x-y coordinates of the center of zone  855  for each perimeter actuator assembly  810  intersecting with data points that are coincident with the plane of the O-ring  130  of the transformed measurements. In block  1015 , the transformation module  350  determines the z coordinate of tips  740  intersecting with data points coincident with surface  570 . In block  1020 , the aforementioned coordinates of tips  740  of actuators  710  may be adjusted to accommodate the thickness of any fabric, foam, and/or other material  1110  that will become the transformable mold surface upon which the conformal cap will be made. For those perimeter actuator assemblies  810  where an intersection between the coordinates of zone  855  and the transformed measurements does not exist, in block  1025 , the perimeter actuators  820  keep fully retracted their respective cylinders  890  and perimeter actuators  830  keep fully retract their respective cylinders  880 , as shown at locations  660  of  FIG.  6   . 
     For some head sizes, multiple perimeter actuator assemblies  810  may have calculated coordinates that intersect the transformed measurement data  570  but interfere with each other or with the centrally located actuators  710  if cylinders  720  were extended. For these cases, blocks  1035 ,  1045 , the interfering cylinders  720  are kept retracted, block  1040  and the perimeter actuator assemblies  810  having coordinates that best bisect the distance between adjacent actuator assemblies  810 , block  1050 , are retained as in block  1060  and any remaining interfering perimeter actuator assemblies  810  have their cylinders  880 ,  890  fully retracted, block  1025 . 
     In block  1055 , transformation module  330  activates control signals to move perimeter actuators  820  of the transformable mold  630  to the x-y positions that correspond to the transformed measurement data  570  of the O-ring  130  and to the “best-fit” positions determined in step  1060 . In block  1065 , the transformation module  350  determines the z coordinate of tips  870  intersecting with data points coincident with surface  570  with adjustments accommodating material thickness  1110  if implemented. In block  1070 , the cylinders  880  and rods  860  of perimeter actuators  830  are extended to establish the z-profile of the perimeter. Also, In block  1070 , the interior actuators  710  are activated within the interior space circumscribed by the perimeter established in blocks  1055 . 
     In block  1080 , a thin, conformable durable fabric  1110 , such as outer wear clothing material is placed on the transformable mold  630 , block  1080 , having correctly positioned actuator tips  740 ,  870  and as shown in  FIG.  11   . The movable rods  860  of the actuators  830  attached to cylinder  880  represents its tip  870 . Tips  870  and tips  740  of cylinder  730  are smooth and rounded to prevent damage the soon-to-be formed cap resting on top of the transformable mold  630 . Preferably, as in block  1085 , after the fabric  1110  or foam  1310  is positioned on the transformable mold  630 , the covered transformable mold  1120  is scanned robotically or by the method of block  240  of  FIG.  2   . As in block  1090 , the newly scanned data measurements taken on the actual x-y-z coordinates implemented in the transformable mold  630  are compared to calculated locations of steps  1010 ,  1015  for quality control purposes. Comparative analysis of scanned tool data to original scanned measurement data  190 , as in blocks  1095 , may suggest iteratively repeating the tool&#39;s actuator positioning functions from blocks  1010 ,  1015  until the resulting transformable mold  630  is within acceptable tolerances, such as two millimeters or less. 
     For selective thermal treatment of the head, the conformal cap created as described herein may be used to create head gear  1210  as in  FIG.  12   . To manufacture head gear  1210 , a single continuous flexible and thermally conductive coolant tube  1220 , 13-18 meters in length, is wrapped tightly around the transformable mold  630  covered with fabric  1110  or foam  1310  starting at the z′ plane and wrapped contiguously towards the crown in the z-direction until the minimum recommended radius of the tube  1220  is reach, such as described in U.S. Pat. No. 10,806,626 B2 issued 20 Oct. 2020 entitled Method and Apparatus of a Self-Managed Portable Hypothermia System to Zumbrunnen et al. and U.S. patent application Ser. No. 17/019,301 filed 13 Sep. 2020, U.S. Patent Application Publication No. US 202110022915 A1, published 28 Jan. 2021 entitled Method and Apparatus of a Self-Managed Portable Hypothermia System to Zumbrunnen et al., herein incorporated by reference in their entirely. On each end is an appropriate length of tube  1220  extends beyond the head gear  1210  for connection to a separate device that provides fluid to be pumped through the tubing  1220 . A coolant passes through the tube  1220  from inlet  1230  to outlet  1240  and the cap&#39;s hypothermia effectiveness is directly related to how well it contacts the flattened hair layer caused by the conformal cap. The flexible tube material  1220  allows for some additional conformity to the head shape beyond that generated by the transformative mold  630  and also provides a degree of comfort to the wearer. The wrapping process may take less than fifteen minutes under ideal circumstances. 
       FIG.  13    illustrates the use of the transformable mold  630  to create a custom padded helmets or other head covering. Approximately 0.1-0.3 square meters of high impact absorbing foam  1310  is formed  1320  over the transformed mold  630  from the top downward. At z=0 location any excess foam is cut off with a knife or razor blade. 
     At locations determined by the application for the custom cap, sensors or housings may be located either between conduits or through the absorbing foam. For example, multiple thermal sensors can be located for scalp temperature sensing, or microwave radiometers can be located for brain temperatures, or EEG sensors can be located for brain electrical activity. Once the tubes are wrapped or the foamed formed and sensors installed, an adhesive  1250  is applied over the outside of the tubes (shown in  FIG.  12    at only one location for clarity). The adhesive can be applied at only selective locations for additional flexible properties if desired. Ideally, the durometer of the cured adhesive is low enough to not inhibit the flexible characteristics of the conduit or foam. About one hour after starting the adhesive application and before full cure of the adhesive, the cap can be removed from the tool if desired. Once removed, the fabric cap may be reserved for future use and the cylinders can be repositioned for making the next custom cap. 
     Several embodiments and variations of the invention have been described above. One of ordinary skill in the art will appreciate and understand the depth and breadth of the description above. The invention, however, is set forth in the following claims.