FR2855959A1 - Personalized equipment e.g. orthosis, manufacturing method, involves sweeping across surface of body part with bright light beam, and acquiring three dimensional representation of body part - Google Patents

Abstract

The method involves sweeping across the surface of body part, intended to receive a personalized equipment e.g. orthosis, with a bright light beam. A three dimensional representation of the body part is acquired and modified by a virtual interactive modeling unit. A piloting file of a manufacturing machine is generated from the modified three-dimensional file. An independent claim is also included for equipment for implementing a method of manufacturing a personalized equipment.

Description

PROCESS AND EQUIPMENT FOR MANUFACTURING A

PERSONALIZED EQUIPMENT

  The present invention relates to a method for manufacturing personalized equipment, in particular but not exclusively an orthosis, for example an orthopedic corset.

  A first solution is known in the art, consisting of molding the part of the body which is to receive this equipment, with plastered strips. This molding allows a blank to be produced. This blank is then shaped by an operator to adjust the shape.

  The orthosis is then produced by thermoforming on this reworked blank. This process collects several interventions: The orthopedist first takes the patient's impression by molding it using plaster strips applied directly to the patient.

  Once the plaster has been taken and removed from the mold, there remains a shell which represents the imprint of the body, the orthopedist pours liquid plaster into this hollow and thus obtains the plaster representation of the shape of the patient's body.

  The orthopedist shapes this form directly by removing it with a chisel or rasp and by adding plaster, the orthopedist colors the different layers of plaster to keep reference marks, in order to create the apparatus best suited to the morphology patient. This shape serves as a forming matrix.

  When the matrix is finished, the orthopedist deforms heated thermoplastic plates by applying them to it.

  The form obtained is a plastic shell in which the patient lodges to be supported.

  This process requires great operator skill and a long preparation time. In addition, taking an impression is tedious and uncomfortable for the patient.

  A solution has also been proposed in the prior art based on the acquisition of a three-dimensional image. Certain developed methods make it possible to scan a part of the body using a laser scanner, but present difficulties when it comes to identifying regions, such as bony protuberances, which require a modification in the profile. internal of the receiving cavity of a member. Difficulties have also been encountered in programming software flexible enough to make the appropriate modifications. US patent US5432703 describes a system for producing a device, such as a prosthetic or orthodontic structure, an internal surface of which must be applied to a part of the human body. In the cavity produced from the mold obtained with the present system, the bulge regions constitute areas of lightening in the surface of the structure and the regions of narrowing constitute zones of higher pressure in the surface.

  The manufacturing method according to this prior art document is intended to be used in a prosthetic, orthopedic or similar device having an internal surface intended to be in contact with a part of a human body, comprising the scanning of the body part with a laser digitizer for providing multiple contour coordinates representing an external contour of the body part along several closely spaced lines read by the laser scanner, storing the contour coordinates representing a digital image of the contour of the body part, the creation of a code from the digital image for the control of a machining machine intended to form a mold having an external surface whose contour is similar to that of the body part , and the creation of the structure from the mold, improved in that it takes into account the effects of the loads applied to the body part and characterized by: a) introducing the body part into a flexible support having a reflective external surface for laser scanning, and applying loads to the body part, b) inspecting the body part introduced and subjected to loads and the location on this site of fundamental modification sites which support the loads and which do not support them, c) the identification of the fundamental modification sites using a series of small markers non-reflective placed on the reflective surface, d) the graphic display of the digital image of the contour and the identification of the sites of fundamental modification of discrete empty points produced by the non-reflective marks, e) the creation of an image numerical modified by selective adjustment of certain discrete voids in fundamental modification sites in a positive manner for the creation of enlargements and adjustment discrete voids in other selected sites of fundamental modification negatively for the production of reductions, f) production of the mold from the modified data with a surface whose contour is similar to that of the surface of the body, but which includes regions of enlargement and reduction, and g) producing the structure from the mold so that the regions of enlargement correspond to the fundamental modification sites which do not support loads and that the regions of reduction correspond to fundamental modification sites carrying loads.

  European patent EP0251720 describes a detector in the form of a prosthesis comprising a single camera assembly and a reflecting surface, mounted on a rotary table and arranged opposite one another to define between them a space for the stump of a patient, the reflective surface being formed to fit between the stump 10 and a leg of the patient, wherein the camera assembly includes a light source and wherein the camera assembly and the reflective surface can rotate together at least 180 on the rotary table, whereby the camera assembly can collect a series of silhouette images of the stump during rotation around the stump.

  The object of the present invention is to provide a method and equipment for implementation on an outpatient basis, with light transportable means and easy to use.

  To this end, the invention relates, in its most general sense, to a process for the manufacture of personalized equipment, such as an orthosis, characterized in that it comprises a first step of acquiring a three-dimensional representation. part of the body intended to receive said equipment, a step of modifying said three-dimensional representation by an interactive virtual modeling means and a step of generating a control file of a machining machine from said modified three-dimensional file.

  According to a variant, the step of acquiring a three-dimensional representation comprises operations consisting in scanning the surface of the part of the body with a light beam for the production of a three-dimensional image, in carrying out at least one digital photograph of said Part of the body.

  Advantageously, the step of acquiring a three-dimensional representation furthermore comprises an operation of reconstructing a three-dimensional image consisting in aggregating the information obtained by scanning and the digital photographs, in order to calculate a digital three-dimensional image.

  According to another variant, the step of modifying the three-dimensional representation is carried out with a force feedback feeler making it possible to control the position of a virtual pointer on the three-dimensional image calculated during the acquisition step, and with devices for activating functions for modifying said three-dimensional image as a function of the position of said pointer.

  The invention also relates to equipment for implementing a method according to at least one of the preceding claims, characterized in that it comprises means for acquiring a three-dimensional image, means for processing said image. three-dimensional image comprising an interactive force feedback sensor controlling the position of a pointer appearing on said three-dimensional image, and calculation means for generating a control file of a machining machine from said modified representation.

  The invention will be better understood on reading the description which follows, concerning a nonlimiting example of embodiment, and referring to the appended drawings o: - Figure 1 shows a view of the mobile acquisition equipment; - Figure 2 shows a view of the digital post-processing station; - Figure 3 shows a view of the machining equipment.

  The mobile acquisition equipment shown in Figure 1 consists of a portable box (1) provided with a carrying handle (2).

  It includes a laser scanner, the lens (3) of which is mounted on the front face of the box, and shooting equipment, the lens (4) of which is mounted on the same front face of the box (1).

  The premet laser scanner achieves an acquisition in the form of point clouds without contact with the patient, with an acquisition time of 0.8 to 2.5 seconds per shot.

  Figure 2 shows a view of the post-processing equipment. It includes a force feedback materialization system (10) provided with a realistic effect tactile arm (11), and a computer (12) providing touch-up processing of the digital file recorded during acquisition with the equipment. mobile.

  Figure 3 shows a view of the machining equipment. It comprises a tool holder (20) actuated by mobile beams (21, 22, 23) along three perpendicular axes, the tool holder itself being mobile along a transalation axis and an axis of rotation. It supports a tool such as a milling cutter (24).

  The process implemented with this system comprises the following stages: Acquisition without contact - Modification of the acquisition - Restitution of the modified form.

  It is implemented by a mobile assembly comprising: - An optical acquisition system by triangulation of a laser light beam, portable A software for modifying point clouds - A fixed assembly composed of: - Software for creating machining paths by material removal - A milling machine for soft materials, it can be replaced by a machine by adding materials per layer for specific applications: design of machining by layers, sintering of materials, stereolithography.

  The contactless acquisition is carried out with a portable optical laser, for contactless probing. The system is compatible with the standards imposed in protected medical and medical environments (clean rooms). Eye safe class 2 laser.

  The system has two functions. The first is an optical system by laser triangulation. The second is to take a digital color photo. The system records the two simultaneous shots, the 3D laser projection and the digital photo. The camera must be portable, light, usable on a stand or on the fly with measurement taken in less than a second.

  The camera is autonomous and stores in an internal memory the information which will then be transmitted to a computer.

  An internal LCD screen allows viewing of the shot.

  A device without integrated screen and without memory can be used provided that it is connected to a laptop, in this case, handling will be less easy.

  A desktop computer can be used, in the case of a furnished room, the operator can empty the memory of the number system on his computer or be connected by cable to the computer.

  The principle of triangulation by laser or by other light source implements a light plane which is created by the light source.

  The light plane quickly scans the field of view, passing through a rotating mirror controlled by a precise galvanometer.

  Light is reflected from the surface of the scanned object. It passes through a transparent object.

  The structure of each scanner line is analyzed and captured by a CCD camera.

  The contour of the surface is the result of the silhouette of the image reflected by each line of scanner.

  A digital photo is captured simultaneously by the same camera.

  The instrument covers a volume between 110X80X40 mm and 1200X900X750 mm and creates between 300,000 and 76,000 pixel points depending on the precision requested by the operator, the shooting distance between 0.6 and 2.5 m.

  The 2D color photo serves as a visualization and allows easier identification during the assembly of the various point clouds originating from multiple shots of a subject.

  The 2D photo can be projected onto the 3D model to give it the appearance of the original (in virtual reality). 25 This is useful for specific applications After scanning, the operator has the choice between combining images on site if he is equipped with modification and modeling software.

  It can transmit the files over the Internet to an appropriate processing center equipped with the modification software. A computer program to gather the views and recreate the subject in 3D at scale 1. This software performs the functions of merging the various digital acquisitions. This intermediate software can only be used in the case of shots of a perfectly fixed subject, this is not the case with human body scans and especially subjects treated in orthopedics.

  The information collected is transformed into 5 standard files, STL, DXF, OBJ, ASCI points, VRML, for communication with other programs.

  Modification of the acquisition: The modeling software is an interactive modeling tool, using the skills of making 10 classic physical models in the digital environment.

  This modification and modeling program linked to the system is the center of the realization.

  It receives the point clouds collected during the digitization.

  These points, called VOXEL describe the volume, the points constituting the flat graphic image are called PIXEL.

  The orthopedist will work the point cloud in space thanks to a tactile interface. The software interface introduces touch into three-dimensional modeling, without the restrictions generated by computer complexities, mathematical equations, keyboard and mouse commands, it models freely.

  The operator is in direct interaction with the physical form, he touches it and can thus replace it in space. It brings together the different 3D images of the patient by correcting any imperfections in the shot caused by small changes in the patient's position during the captures.

  The modeling system is as intuitive as the plaster modeling that the orthopedist is used to. The software tools use working techniques from modeling, such as scraping and cutting.

  Accessing the possibility of controlling these tools with the sense of touch, the orthopedist is in direct contact with the virtual molding of the patient. In addition, the flexibility and freedom offered by touch modeling, the interaction of direct modeling and common tools help to eliminate long learning sessions. The software depends on its interface device which the operator holds in his hand like the handle of his tool.

  The modeling tools include one or more tools among those mentioned above: - Tool of ball, cube, scraper, gouge, spatulas shapes.

  - Sculpting tool guided along a curve.

  - Pushing tool with adjustable zone of influence.

  - Attraction tool allows the material to be extruded.

  - Smoothing tools of different influences.

  - Material supply tools in the form of balls, cylinders or tubes.

  The 2D design tools include one or more of the above tools: Pencil, Line, Arc, Circle, Ellipse, Box.

  Cut, move, rotate, mirror, offset.

  The curve modeling tools include one or more tools among those mentioned above: 25 -Cut a model by a curve.

  -Remove material along a curve.

  -Raise or lower an area on the model relative to a curve.

  - Create a groove or ridges along a curve.

  The 3D curve tools include one or more of the above tools: - Projection of the curves on the model.

  - Creation of a curve on a cutting plane of the model.

- Curve symmetry.

- Copy and paste of curve.

  - Division of curves into separate curves.

  - Curve mapping on the 3D model.

  The assembly tools allow you to: - Create a new part in the current model.

  - Insert an already existing model in the model in 10 lessons.

  - Create an offset according to a precise and defined value, inside or outside the current part. This creates nuclei.

  The productive functions allow: - The cancellation or the resumption of the previous modification levels.

  - The symmetry of the whole model, the plane of symmetry can be placed interactively by dragging it to the screen anywhere and in any orientation in space.

  - Copy and paste lets you select and save entire models and reuse them by pasting again.

  - The gray level projection allows the operator to create engravings on the model by adding reliefs or removing them.

  The tool control functions including: - The mask protects certain areas of the model from any change.

  - The introduction of non-deformable and non-modifiable parts in the project.

  - The constraints make it possible to limit the movement of the tool to a plane chosen for finer control of the tool.

  The analysis functions perform the functions of: -Measuring distance between two points or between two models.

  -Measures the thickness of the model interactively.

  -Measurement between two different pieces.

  -Measuring radii of curvature of the surface of a piece.

  -Line of joint plane allows checking the demolding direction and the undercut zones.

  The display functions perform the functions of: 15 - Translation, zoom, rotation - Adjustment zoom on the screen of the current part.

  - Visualization of a section of the model according to a plan.

  Data import is carried out, for images, in BMP format, for three-dimensional representations according to STL, OBJ, PLY formats.

  The solution includes function libraries, for tools for automatic correction of holes, open faces, inverted normals.

  The data is exported, for the 25 images, in BMP format, for three-dimensional representations according to the STL Binary and ASCII, OBJ, ZCP, PLY formats.

  The operator, if equipped with dedicated software can prepare the return. Alternatively, it can send the 30 files over the Internet to an appropriate processing center equipped with the rendering software.

  The modified form is restored using integrated 3D model machining software and the numerically controlled milling machine designed for the manufacture of corsets and seat corsets.

  An interactive and intuitive solution, simple to prepare a machining in a few minutes consists in: -Place the model in its machining position.

  - Choose a cutter and a type of machining. The software automatically calculates the tool path, for example provided with a 3 to 5 axis milling head for roughing and finishing, with a hemispherical, cylindrical, flat conical and ball, toric cutter 10.

  The 4-axis coordinate system is of the cylindrical or conical type, vertical or horizontal plate.

  The equipment includes means for interactive transformation of the geometric of the model: Copy, translation, rotation, change of scale, symmetry, reversal, alignment, definition of the position of the origin on the automatic machine, automatic management reversals, blanks and fasteners and definition of parallel plane machining (x, y) spiral machining (square, round and elliptical). The numerically controlled machine is controlled by a machining file transmitted to the PMAC Turbo numerical control, the parameters of which have been studied to receive the point files generated by the machining software.

  The machine has two functions: 3-axis flat machining and 3-axis rotary machining.

  It is in the form of a beam (X) supporting the vertical axis (Z) circulating on two parallel rails (Y) driven by ball screws. In two working zones, it is open on one side for flat machining on the other side for horizontal rotary machining, this part can be covered to lengthen the flat machining part.

  The operator for patient placement may use additional holding devices made of colorless transparent material. The ray of light will be reflected by the opaque subject visible through the colorless holding instruments.

  A colorless transparent seat (Plexiglas), gutters, tube, colorless transparent plastic plates will be used as an aid during the shooting. As well as inflated cushions, or strips and films of colorless transparent materials can be used to support the patient during the measurement.

  Black is perceived as a hole by optical systems. The operator for the direct support of a patient can use black gloves. Thanks to the modification software, the loss of data at the place of maintenance can be remedied.

  For better identification, the operator can place black dots or black marks on the patient's skin or on tight-fitting clothing: a tight-fitting sock 20 with black reference points during the measurement of a foot. In the case of a stump, it is important to identify the front and rear shots.

  Uses of the system include adaptations of materials and tools which require precise molding of the human body for personalization.

  It also allows the design of custom-made orthopedic equipment perfectly suited to the morphology: - Support corset for disabled and injured - Equipment requiring molding and modification.

  - Artificial limb, arms, leg, hand, foot.

- Seat corset for the disabled.

- Splint - Morphological mask.

  - Compression mask for skin grafts.

  (badly burned) - Orthopedic shoe.

  - Tailor-made equipment for disabled athletes - Design of custom shoes - Creation of custom clothing or parts of clothing: jacket, pants, hat, helmet, leg warmer - Design of custom tools close to the body; 10 backpack, rifle butt, targeting and protective helmet - Design of custom tools extending the body; handle, tool handle - Custom seat design; bucket seat 15 for competition car, bicycle saddle, riding saddle - Technical clothing adapted to the morphology: point of dance shoes.

  The equipment also finds applications: - in cosmetic surgery, such as the molding of body parts and modification in order to visualize in 3D the modified morphology.

  - in the judicial field for the reconstruction of faces and other body parts in 3D from 25 digital bones.

  - in the field of archeology for the digital molding of an old work and recreation of the missing parts.

  - in the artistic field, for the production of 30 cinema and theater masks adapted to the morphology of the wearer.

  - in the industrial field, for the acquisition of the basic shape and creation of the dies of all sizes of rubber boots and the acquisition of the basic shape and creation of the dies of all sizes of rubber gloves.

Claims (3)

  1 - Method for manufacturing personalized equipment, such as an orthosis, characterized in that it comprises a first step of acquiring a three-dimensional representation of the part of the body intended to receive said equipment, a step of modification of said three-dimensional representation by an interactive virtual modeling means and a step of generating a control file of a machining machine from said modified three-dimensional file.   2 - A method for manufacturing personalized equipment according to claim 1 characterized in that the step of acquiring a three-dimensional representation comprises operations consisting in scanning the surface of the part of the body with a light beam for the production of a three-dimensional image, taking at least one digital photograph of said part of the body. 20 3 - A method for manufacturing personalized equipment according to claim 2 characterized in that the step of acquiring a three-dimensional representation further comprises an operation of reconstructing a three-dimensional image consisting in aggregating the information obtained by scanning and digital photographs, to calculate a three-dimensional digital image.   4 - Process for the manufacture of personalized equipment according to any one of the preceding claims, characterized in that the step of modifying the three-dimensional representation is carried out with a force feedback feeler making it possible to control the position of a virtual pointer to the three-dimensional image calculated during the acquisition step, and with peripherals for activating functions for modifying said three-dimensional image as a function of the position of said pointer.   - Equipment for implementing a method according to at least one of the preceding claims, characterized in that it includes means for acquiring a three-dimensional image, means for processing said three-dimensional image comprising a probe interactive force feedback controlling the position of a pointer appearing on said three-dimensional image, and calculation means for generating a control file 15 of a machining machine from said modified representation.