human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "singular curves and cusp points in the joint space of 3 rpr parallel manipulators"
  Abstract: This paper investigates the singular curves in two-dimensional slices of the joint space of a family of planar parallel manipulators. It focuses on special points, referred to as cusp points, which may appear on these curves. Cusp points play an important role in the kinematic behavior of parallel manipulators since they make possible a nonsingular change of assembly mode. The purpose of this study is twofold. First, it reviews an important previous work, which, to the authors' knowledge, has never been exploited yet. Second, it determines the cusp points in any two-dimensional slice of the joint space. First results show that the number of cusp points may vary from zero to eight. This work finds applications in both design and trajectory planning.

Connected through hyperedge HE-1 (induced by source paper "singular surfaces and cusps in symmetric planar 3 rpr manipulators"):
  with members:
    - "kinematic analysis of a class of analytic planar 3 rpr parallel manipulators"
    - "non singular assembly mode changing motions for 3 rpr parallel manipulators"
    - "definition sets for the direct kinematics of parallel manipulators"
    - "degeneracy study of the forward kinematics of planar 3 rpr parallel manipulators"
    - "workspace and assembly modes in fully parallel manipulators a descriptive study"

Connected through hyperedge HE-2 (induced by source paper "a study of the singularity locus in the joint space of planar parallel manipulators special focus on cusps and nodes"):
  with members:
    - "non singular assembly mode changing motions for 3 rpr parallel manipulators"
    - "definition sets for the direct kinematics of parallel manipulators"
    - "an algorithm for computing cusp points in the joint space of 3 rpr parallel manipulators"
    - "workspace and assembly modes in fully parallel manipulators a descriptive study"

Connected through hyperedge HE-3 (induced by source paper "non singular assembly mode changing motions for 3 rpr parallel manipulators"):
  with members:
    - "architecture optimization of a 3 dof translational parallel mechanism for machining applications the orthoglide"
    - "definition sets for the direct kinematics of parallel manipulators"
    - "an algorithm for computing cusp points in the joint space of 3 rpr parallel manipulators"
    - "degeneracy study of the forward kinematics of planar 3 rpr parallel manipulators"
    - "the kinematic analysis of a symmetrical three degree of freedom planar parallel manipulator"
    - "workspace and assembly modes in fully parallel manipulators a descriptive study"

Connected through hyperedge HE-4 (induced by source paper "singular curves in the joint space and cusp points of 3 rpr parallel manipulators"):
  with members:
    - "definition sets for the direct kinematics of parallel manipulators"
    - "a classification of 3r orthogonal manipulators by the topology of their workspace"
    - "workspace and assembly modes in fully parallel manipulators a descriptive study"

Connected through hyperedge HE-5 (induced by source paper "singularity surfaces and maximal singularity free boxes in the joint space of planar 3 rpr parallel manipulators"):
  with members:
    - "architecture optimization of a 3 dof translational parallel mechanism for machining applications the orthoglide"
    - "definition sets for the direct kinematics of parallel manipulators"
    - "workspace and assembly modes in fully parallel manipulators a descriptive study"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.RO(Robotics)