Biomimetic Hybrid Tactile Sensor with Ridged Structure That Mimics Human Fingerprints to Acquire Surface Texture Information

For robots manipulating objects, more sophisticated manipulations would be possible if surface information about the object were available. This information becomes even more critical when the manipulation is to be carried out in an unstructured environment. Tactile sensing has been the norm for collecting such surface information. In this paper, a sensor for recognizing surface texture was developed, in which a ridged structure on its surface, which generates vibrations when moved along the surface of the object of interest, is used. The pattern used for the ridged structure combines two distinct patterns that are found in different parts of a human fingerprint. In this work, sensors with two distinct fingerprint-like structures were first developed and tested to acquire surface texture information. Texture features were also extracted and identified with these sensors. Then a hybrid pattern was created by combining the two previously tested distinct structures. Finally, a series of experiments was conducted to compare the performance of sensors with a ridged structure having a single fingerprint pattern and a hybrid sensor whose ridged structure consists of two fingerprint patterns. In the experiments, the sensors collected surface information from nine different textured samples. Through these experiments, it was confirmed that the sensor using the hybrid pattern has better surface identification capabilities than the sensors using a single pattern.