Abstract
In order to cause a tactile sensor to be thin shape, a new optical tactile sensor is developed by applying CT(Computed Tomography) algorithm. The present tactile sensor is comprised of infrared emitting diode array, the receiving phototransistor array and transparent silicon rubber plate. Infrared rays emitted from the diode array are directed into an end of the plate and their intensity distribution is measured by the phototransistor array mounted on the other end. If CT algorithm is directly applied to the tactile sensor, there are two defects such as shape of sensing area limited to a circle and long calculation time. Thus, a new CT algorithm oriented to tactile sensing is proposed to overcome these defects. In the present algorithm, a square sensing area is divided to an n-by-n array and algebraic equations are derived from relationship input and output light intensities on assumed light projections. Several reconstruction methods are considerable to obtain pressure values caused in the squares. In the present study, ART(algebraic Reconstruction Technique) and LU decomposition methods were employed and these methods were compared to select the best reconstruction method In a series of simulations, it was found that the ART had an advantage for the present typed tactile sensors' reconstruction method because of variability of calculation error.
