Determining independent contacts regions to immobilize 2D articulated objects

This paper deals with the problem of determining independent contacts regions (ICRs) on 2D articulated objects, such that a finger contact in each region guarantees a force-closure (FC) immobilization, independently of the exact position of the finger. These regions allow a robust finger or fixture placement on the links of the articulated object, despite of possible errors in the position of the contacts. The proposal defines a generalized wrench space for articulated objects and then computes the ICRs starting from an initial FC grasp, considering frictional contacts. The approach has been implemented, and some illustrative examples are provided.