Bioinspiration from Biodiversity in Sensor Design
Published in ASME 2001 International Mechanical Engineering Congress and Exposition, 2011
Biological systems are organized along a hierarchy that ranges from bio-molecules to large-scale ecosystems. In the present work, the level of biodiversity is considered as a source for engineering knowledge. In the process of evolution and adaptive radiation in particular, common functional principles have been adapted to suit a multitude of tasks and constraints. The resulting biodiversity can hence be regarded as a source for inspiration on how a single functional principle can be adapted to suit the requirements of different applications. The biosonar systems of bats are an example for a biological sensing principle that has been adjusted to fit a multitude of sensing tasks. The unique combination of biosonar sensing and flight has allowed bats to settle almost the entire land surface of the earth and exploit a wide range of food sources that range from airborne insect prey to terrestrial vertebrates. The geometries of the mechanical baffles that surround the sides of sound emission and reception are a conspicuous correlate of this diversification in the uses of biosonar. Understand the principles that underlie this diversification, requires an array of customized methods: First, objective and quantitative descriptions are needed for the biological variation in irregular, organic shapes at an inter-specific level. Second, functional features of the sensors must be characterized in a similar fashion. Finally, a link between form and function needs to be established. A description of the biodiversity in shape requires some form of registration between shapes from different species. For the outer ears of bats, this problem has been addressed by virtue of an ad-hoc method that represents the ears in cylindrical coordinates with a reference frame that is fixed through a potential field in analogy to the interactions between molecules. An alternative method that is likely to generalize to more difficult geometries such as the noseleaves of bats can be based on modal analysis. In the process of \"spectral embedding\" the location of pinna surfaces is expressed in a space that is spanned by the amplitudes of different modes at the respective positions. For the acoustic function of diffracting baffles local features such as grooves and ridges can be of prime importance. These are not easily captured by methods that are more likely to provide robust estimates of variability in a sample at low spatial frequencies. Hence, local shape descriptors capable of quantifying these features are needed. sonar, local shape, pca, shape space
authors: Rolf Mueller and Jianguo Ma and Zhen Yan and Washington Mio and Cindy Grimm
Authors: Rolf Mueller and Jianguo Ma and Zhen Yan and Washington Mio and Cindy Grimm
Download Paper