Application of Rapid Manufacturing for the Production of Custom Hearing Instruments

Transcription

1 1 Application of for the Production of Custom Hearing Instruments Steven Green Siemens Hearing Instruments Ltd, Crawley. 2006

2 2 The hearing aid business has been one of the first industries to apply rapid prototyping technology for the industrialised mass production of personalised devices. This has enabled fundamental changes in the entire workflow and supply chain of individually shaped in-the-ear hearing instruments. 3D scanners can now be used to digitise the individual ear impression directly in the audiologists practice. Electronic orders containing all required anatomical and audiological information can be transmitted instantly via the internet to the hearing aid manufacturer. New design and production methods based around CAD and RP allow revolutionary new product concepts and increased quality levels. The interaction between end user, hearing healthcare professional and hearing aid manufacturer is changing dramatically. This presentation explains the impact of Rapid Manufacturing on the transformation of the supply chain for hearing instruments, describes the current status and gives an outlook into potential further developments.

3 3 Contents of custom hearing instrument shells Technology overview SLS / SLA / DLP

4 4 Siemens Hearing Instruments UK Ltd Siemens Audiologische Technik (SAT) is the hearing instrument division of Siemens with headquarters in Erlangen, Germany SAT is 100% owned by Siemens Medical Solutions SAT is world market leader in the development, production and distribution of hearing instruments SAT has a worldwide network of subsidiaries with key R&D and production centers in Erlangen (Germany), Piscataway (NJ/USA) and Singapore Siemens Hearing Instruments Ltd is the UK subsidiary with 140 employees in sales, production and customer service located in Crawley, serving customers in the NHS and in the private retail sector

5 5 Basic Styles of Hearing Instruments BTE Behind the Ear Instruments: Individualised ear piece - Instruments are manufactured in large quantities as non customised serial products - Amplified sound is fed in to the ear canal with a tube and an individualised earpiece (ear mould)

6 6 Basic Styles of Hearing Instruments In the ear instruments: ITE - Custom made for each ear according to individual ear canal geometry, hearing loss and selected options - Electronic components pre-produced and assembled on a face plate

7 7 Amplifier Technology Microphone Pre-amplifier Final-amplifier Receiver AD DA Digital Signal-or - Fully digital, adaptive signal processing in multiple frequency channels. Algorithms for noise reduction, feedback cancellation, classification of acoustic environment - Multi microphone arrays for adaptive directional microphones - Wireless link for binaural synchronisation of right and left instrument - Proprietary, ultra low power chip sets (3 x 4 mm 2, 800uA, 1.0V)

8 8 Traditional Manufacturing Silicon Ear Impression, shipped by mail together with handwritten order form Manual cut & trim Negative cast Manual Detailling: Trim down to final size Negative cast of trimmed shape Production of a hollow shell by pouring UV curable resin into cast Manual creation of vent canals Finished shell Final cut after Testing fitting of components Assembly of Electronic components Attach face plate: Glue, cut, buff Quality Test

9 9 Digital Shell Production Silicon ear impression Digitize shape of ear impression with a specialized 3D scanner (attention: undercuts!) 3D data set represents shape of the uncut ear impression (point cloud) ing of the virtual shell with specialized 3D CAD SW (unprocessed data set serves as reference) Virtual design including placement of components and collision detection (Design to Quality) Generation of a Build Package for production of a large batch of shells on a RP machine Production of shells with a RP machine (e.g. SLS, SLA, DLP, 3D Printer) Post ing: removal of supports, washing, polishing Design of the entire custom made product in the virtual domain using parts library and validated design rules. Avoids operator dependent variations Finished instrument Final Assembly and quality checks simplified due to CAD design and inherent design to quality

10 10 Digititizing of Ear Impressions Variety of Ear Impressions 3D-Scanner 3D- Point Cloud Turntable

11 11 Virtual ing of Ear Impressions Ear impression is trimmed down to final size of the instrument. Unprocessed data serve as reference.

12 12 Modelling of Shell and virtual Placement of Components Point Cloud Faceplate Virtual Shell Creation of Vent Canal

13 13 Shell Production and Assembly Build Package Finished Instrument Assembly Laser Shell production Cleaning Finished Shell

14 14 RP for Manufacturing of Hearing Aid Shells SLS: Selective Laser Sintering: - Nylon powder is fused layer by layer by a Laser beam 3D Systems Laser-Sintering System Pro: - no supports required - good biocompatibility Con: - limited resolution - high investment

15 15 RP for Manufacturing of Hearing Aid Shells Stereolithography SLA: -Laser cures liquid resin layer by layer - capacity: 80 shells / 8h Pro: - high accuracy - widely used in the h.i. industry Con: - Supports required - Biocompatibility requires careful material and process optimisation 3D Systems Viper SLA

16 16 New Possibilities: Integration of Snap-in Modules instead of glue-on faceplates Modul: Microphone, Electronics, Battery Shell design includes snap-in features Modul integration with virtual shell Service friendly modular design

17 17 New Possibilities: Integration of Snap-in Modules instead of glue-on faceplates Service friendly: No cracking of glued connection between shell and faceplate if components need replacement Component placement can be simulated to achieve smallest possible size and avoid component collision (risk of acoustic feedback or electrical fault) Virtual design freeze: Minimized variability in final assembly increased quality

18 18 New Possibilities: Supply Chain Integration with Office Impression Scanner and e-ordering Inexpensive and easy to use 3D impression scanner for use in the hearing aid dispensers office Scan information can be used in the counselling process to determine the correct model and shell size for the patient Electronic order forms allow instant validation of order information and transmission of all relevant order data via internet.

19 19 Office Impression Scanner - iscan Principle of 3D Data Acquisition with Colour Coded Triangulation Avoids expensive components (Laser, high precision mechanical components) Uses smart self-calibrating algorithms to achieve high precision P z h, P y Color Code Projector Basis B C x Camera

20 20 New Possibilities: Office Impression Scanner Integration of counselling and e-ordering iscan (scan) CONNEXX (counsel&select) OCM (order) etona (send&receive) Send order receive status Manufacturer BackEnd SW

21 21 User Benefits: Improved Communication Comments and special instructions can easily be attached to 3D data scoop crus area 2 smooth rough area 1 cut canal tip here 2 preserve dent

22 22 User Benefits: Manage Customer Expectations Software can calculate buildability of a particular model for the individual ear canal geometry and hearing loss using scan data and order information Feature helps counselling process and increases customer satisfaction

23 23 iscan & eordering Benefits Scan the impression in the office and transmit electronically Cost and time saving No risk of damage or loss in shipment Time limitations: 24/7 access Smart Electronic Order Form Instant validation of order against our manufacturing rules avoids clarification calls at later stage All order information can be stored in the client database Easy tracing of order status via transaction browser On-screen visualisation of ear impression and selected instrument Allows instant validation of the impression & scan quality Annotations can easily be attached to the 3D image of the impression to clarify instructions Buildability index allows judgement of smallest possible shell size Can be used as counselling tool with the customer Helps to manage end user expectations Reduces returns and remakes

24 24 : Complete e-supply Chain iscan & eordering currently support ordering of custom instruments We are working to extend the system towards electronic ordering of: BTEs Ear moulds Accessories Repair

25 25 : Direct Ear Canal Scanning Goal: Direct Ear Scanning without Silicon Impression Various attempts no commercially viable solution yet Challenges: Size: diameter of probe < 2mm Accuracy Undercuts Varying consistency and mechanical properties of tissue along the ear canal patient safety risk of injury cross infection ease of use cost

26 26 Rapid Prototyping have started to replace conventional production methods in the hearing aid industry. Selective Laser Sintering, Stereolithography and Digital Light ing are currently in use for the manufacturing of hearing aid shells and ear pieces. The combination of in-office 3D scanning, e-ordering and digital manufacturing allows a complete re-engineering of the supply chain. These methods allow tighter control over process parameters, improved efficiency and higher overall quality levels. Clear, unmistakable communication and full validation of order data avoid costly and frustrating remakes and returns. Doing the right things right first time