R. S.  Jamisola, Kormushev, P., Bicchi, A., and Caldwell, D. G., ?Haptic Exploration of Unknown Surfaces with Discontinuities?, in Proc. IEEE/RSJ Intl Conf. on Intelligent Robots and Systems (IROS 2014), Chicago, USA, 2014, pp. 1255 - 1260 [Online]. Available: http://kormushev.com/papers/Jamisola_IROS-2014.pdf