  Pick-and-place regrasp is an important manipulation skill for a robot. It
helps a robot accomplish tasks that cannot be achieved within a single grasp,
due to constraints such as kinematics or collisions between the robot and the
environment. Previous work on pick-and-place regrasp only leveraged flat
surfaces for intermediate placements, and thus is limited in the capability to
reorient an object.
  In this paper, we extend the reorientation capability of a pick-and-place
regrasp by adding a vertical pin on the working surface and using it as the
intermediate location for regrasping. In particular, our method automatically
computes the stable placements of an object leaning against a vertical pin,
finds several force-closure grasps, generates a graph of regrasp actions, and
searches for the regrasp sequence. To compare the regrasping performance with
and without using pins, we evaluate the success rate and the length of regrasp
sequences while performing tasks on various models. Experiments on
reorientation and assembly tasks validate the benefit of using support pins for
regrasping.
