Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Carbon nanotube actuators and their applications on example of a drum brake

: Kosidlo, Urszula; Addinall, Raphael; Glanz, Carsten; Kolaric, Ivica

Shahinpoor, Mohsen (General Chair) ; Université de Cergy-Pontoise:
6th World Congress on Biomimetics, Artificial Muscles and Nano-Bio 2011. CD-ROM : 2011 Ocotber 25-26-27, Cergy-Pontoise, Paris, France
Cergy-Pontoise, 2011
11 Folien
World Congress on Biomimetics, Artificial Muscles and Nano-Bio <6, 2011, Cergy-Pontoise>
Fraunhofer IPA ()
Carbon Nanotube (CNT); carbon nanotube sheet actuator; material; functional model; drum brake; Aktuator; Trommelbremse; Verbundwerkstoff

Carbon Nanotubes (CNT) as active materials, due to their strain, low driving voltage, light weight and flexibility, have shown a great potential for industrial applications especially in medical technology.
The driving principle of CNT actuator is electrochemical double layer charging, which necessitates the presence of electrolyte. This represents a major drawback with respect to industrial applicability. This has been overcome by the development of so called "dry" actuators. These are based on CNT-polymer composites, where the electrolyte is encapsulated within the polymer matrix. Such composites have been build up and used as three layer actuators, where two outer layers containing CNTs are considered as active layers and are separated by the middle layer, separator, which serves as electrical isolator as well as an ion reservoir.
The main reason for the development of dry actuator is to bring CNT actuator technology closer to the industry. Up till now plenty of research has been devoted to this material focusing on the generation of fundamental knowledge, understanding of the actuation mechanisms and systematical characterization. Its value should not be underestimated; however, such an approach is often not sufficient to explain the potential of carbon nanotubes as actuators.
For this reason a functional model, utilizing stacks of dry actuators, was designed and constructed. The presented model is a simple drum brake system where stacks of dry actuators are used as the components moving the brake parts as well as generating the force to stop the drum from rotation.
Within this work we present the route towards the development of the drum brake functional model, providing the discussion on some of the most crucial aspects as material and process development, electrical contacts and system integration.
CNT-polymer actuators, although appropriate from the performance point of view, have not yet reached the medical market due to the unknown interactions between CNTs and living organisms. However, the achievements obtained in the development of CNT actuators highlight the potential for applications in other market sectors. CNT actuators could be used as positioning systems, valves and pumps, switches and brakes.