Created: 14/07/2022
Tags: incipient slip, markers, GelSlim
Link: https://arxiv.org/pdf/1810.13381.pdf
Status: Reading
Incipient slip is when parts of the contact region (peripheral) start to slip. The marker displacement in slip region must be smaller than the displacement of the object.
Incipient slip is important
Assumption: the contact patch will move as a planar rigid body and motion of every point in the contact patch can be considered as pure rotation around a point, which is called the instantaneous center of rotation (ICR).
Slip starts at peripheral regions, so we can use the markers in the inner contact region to calculate the estimated displacement field of markers.
When the real displacements of several points in the contact region are sufficiently different from the estimated displacements, we trigger incipient slip.
In experiments, only one sensor is used for slip detection
For objects with flat and smooth surfaces, a large gripping force is needed to make the method reliable.
The method can detect any directional slip without any prior knowledge of the grasped object.
It can be potentially applied to many manipulation tasks that requires slip detection feedback, such as grasp force control, in hand manipulation, and tool use.