CHAPTER 5. Conclusion and future research directions
moves the fingertips of the robotic multi-fingered hand on the current available
reconstruction surface towards points which are optimal (in a local sense) with
respect to a certain number of indices weighting both the quality of the grasp and
the kinematic configuration of the robotic hand. It is worth noticing that, in this
work, a new heuristic grasp quality index has been proposed, but any other quality
measures may be chosen in substitution of the proposed one, without effecting the
general framework: the only thing to point out is that any other index should just
ensure that it can be applied to discretized surfaces of the objects, as shown in the
Appendix A. At the end, a control module must ensure that the references given
by the planner are correctly followed by the robotic hand.
Once the unknown object has been grasped, one could assign to it a desired
motion for a particular task. In such a case, a framework for a coordinate and dex-
terous manipulation should be considered. For this reason, a kinematic model for
motion coordination of a redundant multi-fingered robotic hand has been derived,
which allows to compute the object's pose from the joint variables of each finger
of the robotic hand, as well as from a suitable set of contact variables. Moreover,
a prioritized inverse kinematics scheme with redundancy resolution, both with in-
verse and transpose Jacobian matrix, has been developed. This algorithm can be
used for kinematic control as well as for a local planning method for dexterous
manipulation.
5.2
Proposals for the future
Likewise performed in the previous section of this chapter, the directions for future
researches can be also split in three parts.
For what concerning the reconstruction of objects' surfaces, proposals are lead-
ing at overcoming some assumptions given in the section 3.1. In particular, to sat-
isfy some possible industrial requirements, the object could be also in movement
with respect to the base frame and some research directions are trying to overcome
the problem about the topology of the object. Some results about this last aspect
have been already reached, but this goes beyond the goals of this thesis.
About the quality measures for the grasp, several efforts are addressed in the
fulfilment of global optimal grasps instead of just local optima. To accomplish this
task, some studies aimed at emplying touch sensors to refine the final grasp have
been carried out.
For what concerning the kinematic control method for dexterous manipulation,
the case of study of Figure 4.3 has been built by some students at Universit`a of
Basilicata under the supervision of Prof. Caccavale and Dr. Pierri. A collaboration
has been established with this research team and some experimental works will be
tested under this new experimental platform. In particular, the contact between
the fingertips of the robotic hand and the object will be now dynamic through
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