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Rodents, like mice and rats, use tactile hairs in the snout region (mystacial vibrissae) to acquire information about their environment, e.g., the shape or contour of obstacles. For this, the vibrissa is used for the perception of stimuli due to an object contact. Mechanoreceptors are processing units of these stimuli measured in the compliant support (follicle-sinus complex). We use this behavior from biology as an inspiration to set up a mechanical model for object contour scanning. In a plane, an elastic bending beam sweeps a rigid obstacle while the beam's foot passes by below the object. Prescribing a contour and a list of optional contact points on it, we apply Bernoulli's bending theory for large deformations in order to determine in a first step the elastic lines of the beam and the corresponding reactions of the support (the only observables in biology and technology). Taking these reaction values as data of a bending problem, an initial-value problem redetermines (within certain "measuring noise") the starting contact points. This theoretical one-sweep scanning process is demonstrated by several examples, and their outcomes are compared to experimental results. The current confinements in theory and experimental setup and their removal are explained. A somewhat new topic could be to allow for rotationally elastic bearings of the beam instead of the usually preferred clamp. In contrast to other papers in this field, we deal with nonlinear theory throughout, follow analytical ways as far as possible, and use numerics only to find solutions of final finite equations. : Object contour scanning using elastically supported technical vibrissae r A further and improved method for object localization and shape detection is given in [18] for plane problems, and in [7] for spatial problems. In both works, the authors switch from linear approximation of the curvature to the C

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In this paper the author presents a mathematical model of a device that can be seen as a segment of an artificial worm (following the paradigm "earthworm") and as an artificial muscle as well. Confining considerations to statics, the model shows up as an ordinary parameter-dependent boundary value problem. It is tackled numerically in various particular forms by means of Maple and thus gives a good view of the segment's behavior during inflation and under longitudinal load. Segments of maximal volume present a useful preliminary stage of the investigations.

In this paper the authors consider mechanical devices of rotational symmetry that can be seen as segments of an artificial worm or as a balloon for angioplasty. Continuing former work [7] the segment is now placed within a cylindrical or constricted rigid tube that will be touched or pressed during inflation of the segment. Both the segment's shape and the forces of contact are investigated. The main mathematical tool is the Principle of Minimal Potential Energy -handled as an optimal control problem with state constraint. The necessary optimality conditions are carefully analyzed and simulation results for characteristic examples are presented. The treatment of the problem is primarily mathematical but aiming at application.