PROJECT PLASTIC 2018 third place! Feasibility study of LDS antennas for hearing aid applications

With Laser Direct Structuring, it is possible to trace electrical circuits directly on the surface of plastics. This will increase robustness and design freedom when developing medical devices. This project is chosen as one of five projects that will be pitching at Plastic Engineering Day

This project has been chosen as one out of five projects that will be pitching at Plastic Engineering Day.
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In modern connected devices and especially in medical devices, it is required to create the smallest products possible without compromising functionality. This is possible taking advantage of the properties of plastics as supportive materials, combined with Laser Direct Structuring (LDS).

LDS antennas have never been implemented in hearing aid applications, which called for innovative designs and reliability testing, which paved the way for this thesis. The aim was to study the feasibility of LDS in hearing aid applications by creating innovative and robust connection designs between the PCBA and the LDS antenna. Hearing aids are also exposed to aggressive environments, so the reliability of the solution was evaluated in regards to main critical factors.

The satisfactory results of the project are presented through a systematic product development process, a physical prototype and tests. A final concept design is recommended, and interesting areas for future work are suggested.

 

University and the academic level of the project:

This project was acknowledged as a 30 ECTS weighted workload thesis, and as part of the contentment of the Master of Science degree in Engineering Design and Applied Mechanics at the Technical University of Denmark (DTU).

The work for this project has been realized from the 14th. of September 2017 until the 18th. of April 2018, excluding previous contact about the project definition with GN Hearing and DTU. The involved courses have mainly been micro manufacturing with polymers, materials science, manufacturing technologies for polymers.

The project was carried out at the Section of Manufacturing Engineering at the DTU in cooperation with GN Hearing. The study has been supervised by Aminul Islam (MEK) and Anders Michaelsen Hjermø (GN Hearing).

 

Which type(s) of plastics/production processes are used in your solution?

Different experiments are described in the project, where laser structuring is tested on Polyphtalamides (PPAs), Polycyclohexylenedimethylene Terephtalate (PCT), Liquid Crystal Polymers (LCP), and finally, the chosen polymer was the reinforced polyamide PA4T-GF30 called Fortii® LDS85.

For the solution, a functional prototype was made. It included the main part, which was injection moulded in an aluminium tool, designed by the undersigned. This part was then prepared for Laser Direct Structuring which was carried out with LPKF-LDS® equipment. Other parts were produced by additive manufacturing in the material Visijet M3 Crystal, and the assembly included manual soldering, pin connections and gluing.

 

More information:

This picture shows the final prototype which was tested.
This picture shows a rendering of the CAD model for the hearing aid including LDS antenna.
This picture shows the the machines involed in the LDS process and plating of the plastic parts.

PROJECT PLASTIC is a talent competition for engineering students. The purpose is to celebrate the talented students that as part of their degree lead the way in how to use plastic materials to create innovative solutions. The competition is being administrated by The Danish Plastics Federation.

Read more about PROJECT PLASTIC

The 11 best candidates for PROJECT PLASTIC 2018

PROJECT PLASTIC 2018 WINNER! Håndtering og genanvendelse af plastaffald i Kenya Analyse og udviklingsarbejde med fokus på optimering af proces og højere plastkvalitet hos plastgenanvendelsesfabrik i Kenya.
Link to Håndtering og genanvendelse af plastaffald i Kenya
PROJECT PLASTIC 2018 second place: Project Trebo Projektet Trebo, som nu er blevet til en startup, bidrager med at gøre plastindustrien mere bæredygtig. Trebo har udviklet en ny metode og maskine der kan sortere fuldstændigt blandede plastmængder.
Link to Project Trebo
PROJECT PLASTIC 2018 third place: Feasibility study of LDS antennas for hearing aid applications With Laser Direct Structuring, it is possible to trace electrical circuits directly on the surface of plastics. This will increase robustness and design freedom when developing medical devices.
Link to Feasibility study of LDS antennas for hearing aid applications
Final candidate: DrinkSaver DrinkSaver er et plastik produkt, hvis funktion er at mindske spild, uden at mindske drikkeoplevelsen. Designet er udformet i en rem af plastlameller, som stopper eventuelle spild på en diskret måde.
Link to DrinkSaver
Final candidate: ECO Tray ECO Tray er en håndbagagebakke i genbrugsplast til security i lufthavne. ECO Tray bidrager til grøn omstilling via cirkulær økonomi. Det nye bakkedesign forbedrer både ansatte og passagerers oplevelse uden at gå på kompromis med sikkerheden.
Link to ECO Tray
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Link to Forbedring af magnetiske og mekaniske egenskaber af nylon 6 bundne neodym magneter
Softtooling SOFTTOOLING enables manufacturing companies to produce high precision polymer parts for a fraction of the price compared to current tooling methods. Even better, lead times are reduced from typically 4+ weeks down to a matter of days.
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Link to Ellipsit: Beholdere til et cirkulært løssalgssystem
Technological signature in precision injection compression moulding of polymer Fresnel lenses The optimisation of injection-compression-moulding in Fresnel lens production enhances the replication quality of polymer optics. For the task, the use of optical metrology leads to innovative ways to manufacture plastic products.
Link to Technological signature in precision injection compression moulding of polymer Fresnel lenses
CycleBrick - simple use of recycled plastic in emerging economies This project uses low technology to transform plastic waste into low-cost construction materials. The design is made exclusively with available materials and existing technology in emerging countries.
Link to CycleBrick – simple use of recycled plastic in emerging economies
Fra ide til produktion af den interaktive lanterne GLØD Dette projekt havde til formål at afprøve et fuldt forretningskoncept med design, udvikling, prototyper, fremstilling og afsætning af en lanterne fremstillet i plastik.
Link to Fra ide til produktion af den interaktive lanterne GLØD