Two-dimensional vibrating platform in nm range

IN SENSORY physiology, it is often necessary to apply well defined mechanical stimuli with frequencies in the 10 or I00 Hz range and amplitudes in the nm or mum range. Examples in this field of research are studies of the sensitivity of inner ears, statocyst systems and other mechanoreceptors to substrata vibration occurring in mammals (e.g. moles and small rodents), reptiles, amphibians (toads), arthropods and other invertebrates. In addition, in hearing studies in fish, mechanical stimuli are applied as particle motion stimulates the accelerometer-based inner ear. All these sensory systems can be adequately studied by mounting the whole animal (or limb) on a vibrating platform generating the mechanical stimuli. When developing such a platform, two obstinate problems are met; strong resonance at certain frequencies and cross-talk orthogonally to the non-driven directions. This study shows that the resonance frequencies can be calculated and shifted to physiologically non-relevant high values by changing the system parameters. Furthezraom, it is shown that the crosstalk of the platform is generally negligible. The present design of two-dimensional (2-D) vibrating platfinm was used to stimulate the otolith systems in the fish inner ear (Schellart et al., 1993).