A Biomimetic Tactile Fingerprint Induces Incipient Slip
This work addresses the problem of object manipulation and drop prevention in robotics, offering a practical solution for improving grip control, though it is incremental as it builds on existing sensor designs.
The researchers tackled the problem of detecting incipient slip in tactile sensors to prevent objects from falling, and they achieved this by modifying a biomimetic sensor with ridges to induce and detect local slippage, successfully predicting and preventing drops of several differently shaped objects.
We present a modified TacTip biomimetic optical tactile sensor design which demonstrates the ability to induce and detect incipient slip, as confirmed by recording the movement of markers on the sensor's external surface. Incipient slip is defined as slippage of part, but not all, of the contact surface between the sensor and object. The addition of ridges - which mimic the friction ridges in the human fingertip - in a concentric ring pattern allowed for localised shear deformation to occur on the sensor surface for a significant duration prior to the onset of gross slip. By detecting incipient slip we were able to predict when several differently shaped objects were at risk of falling and prevent them from doing so. Detecting incipient slip is useful because a corrective action can be taken before slippage occurs across the entire contact area thus minimising the risk of objects been dropped.