  Tactile sensing has recently been used in robotics for object identification,
grasping, and material recognition. Most material recognition approaches use
vibration information from a tactile exploration, typically above one second
long, to identify the material. This work proposes a tactile multi-modal
(vibration and thermal) material identification approach based on recursive
Bayesian estimation. Through the frequency response of the vibration induced by
the material and thermal features, like an estimate of the thermal power loss
of the finger, we show that it is possible to identify materials in less than
half a second. Moreover, a comparison between the use of vibration only and
multi-modal identification shows that both recognition time and classification
errors are reduced by adding thermal information.
