As part of pioneering research at the University of Bristol, IDC Models, the rapid prototyping and model making division of IDC (Industrial Design Consultancy), has produced 3D models of the smallest hearing organ known to science. IDC Models pushed its SLA printing technology to the limit when it developed life-size replicas of the katydid (sp. Cophiphora) insect’s ears, using its high resolution Viper SLA machine.
Researcher, Lydia France from the University of Bristol, found it hard to find a company that could make such micro scale models. She comments, “Very few companies offer micro 3D printing, so it was wonderful to get such high quality models from IDC. 3D printing is an amazing tool for science, particularly when researching structures. Before IDC’s models, I had to use a model that was about 1000 times bigger than the actual ear.”
The tiny hearing structure is located in the katylid’s leg and contains a minute membrane, similar to the eardrum, underneath a slit. The research project is focused on understanding how the insects actually hear as their ears are up to 100 times smaller than the sound wave they are listening to. Technically it shouldn’t be possible for them to hear at all, but researchers believe that sound diffraction could make hearing possible.
It is extremely difficult for researchers to conduct experiments into the physics of sound at this micro scale and particularly when minute creatures are involved. Nature is complicated, and 3D printing is the best tool available currently to recreate structures which would be impossible to investigate otherwise.
France explains, “Some parts of animals are far too delicate, or rare to work with, and having an accurate model is invaluable. Another huge benefit of 3D printing is being able to alter structures. For example, I could investigate how a flap works on the ear by having a model with it present, and with it removed. If I was using a real life sample, this would be next to impossible to do without very steady hands and a lot of trial and error!”
The models of IDC’s insect ears are supporting just one of several research projects studying the physics behind hearing. By having a better understanding of alternative hearing methods such as this, research will be able to advance the technology of human hearing aids in the future.