Object contour sensing using artificial rotatable vibrissae
Recent research topics in bionics focus on the analysis and synthesis of mammal’s perception of their environment by means of their vibrissae. Using these complex tactile sense organs, rats and mice, for example, are capable of detecting the distance to an object, its contour and its surface texture. In this paper, we focus on developing and investigating a biologically inspired mechanical model for object scanning and contour reconstruction. A vibrissa – used for the transmission of a stimulus – is frequently modeled as a cylindrically shaped Euler-Bernoulli-bending rod, which is one-sided clamped and swept along an object translationally. Due to the biological paradigm, the scanning process within the present paper is adapted for a rotational movement of the vibrissa. Firstly, we consider a single quasi-static sweep of the vibrissa along a strictly convex profile using nonlinear Euler-Bernoulli theory. The investigation leads to a general boundary-value problem with some unknown parameters, which have to be determined in using shooting methods. Then, it is possible to calculate the support reactions of the system. These support reactions together with the boundary conditions to the support, which all form quantities an animal solely relies on in nature, are used for the reconstruction of the object contour. Afterwards, the scanning process is extended by rotating the vibrissa in opposite direction in order to enlarge the reconstructable area of the profile.