  Reproducing the capabilities of the human sense of touch in machines is an
important step in enabling robot manipulation to have the ease of human
dexterity. A combination of robotic technologies will be needed, including soft
robotics, biomimetics and the high-resolution sensing offered by optical
tactile sensors. This combination is considered here as a SoftBOT (Soft
Biomimetic Optical Tactile) sensor. This article reviews the BRL TacTip as a
prototypical example of such a sensor. Topics include the relation between
artificial skin morphology and the transduction principles of human touch, the
nature and benefits of tactile shear sensing, 3D printing for fabrication and
integration into robot hands, the application of AI to tactile perception and
control, and the recent step-change in capabilities due to deep learning. This
review consolidates those advances from the past decade to indicate a path for
robots to reach human-like dexterity.
