Development of Tactile Actuators : Actuators for arm mounted hearing device

Abstract: This report is a thesis work for a Master of Science in Mechanical Engineering at Karlstad University. More than 8.5 million people in the world are deaf but unable to get cochlear implants. It has been shown that by the use of actuators that stimulate the skin nerves in different patterns, people can learn to feel the sound on their skin. Invencon AB has developed a actuator concept that uses an electromagnetic actuator with a moving permanent magnet. The problem with this concept is that it locks itself in its upper position due to the permanent magnets around it. The aim of this project was to develop a new actuator concept without the problem of locking-up by starting from the beginning through a systematic product development process. Through research of actuator technology, dividing the project into phases and tasks used in the industry and methods presented in literature such as systematic and creative concept generation, a product development project was made on a product with the main function of imprinting the skin in recognizable patterns. It resulted in an actuator concept similar but different to the existing concept. The resulting concept solved the problem presented by utilizing a moving coil instead of a moving permanent magnet. A 3D model was made and a prototype was 3D printed and tested. Future work includes designing a suitable spring, a research on how wire management should be done, how to minimize the environmental impact from transport, if there are any hazardous substances during elimination and if the income from recycled material can be greater than the elimination cost.