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: "a control architecture with online predictive planning for position and torque controlled walking of humanoid robots"
  Abstract: A common approach to the generation of walking patterns for humanoid robots consists in adopting a layered control architecture. This paper proposes an architecture composed of three nested control loops. The outer loop exploits a robot kinematic model to plan the footstep positions. In the mid layer, a predictive controller generates a Center of Mass trajectory according to the well-known table-cart model. Through a whole-body inverse kinematics algorithm, we can define joint references for position controlled walking. The outcomes of these two loops are then interpreted as inputs of a stack-of-task QP-based torque controller, which represents the inner loop of the presented control architecture. This resulting architecture allows the robot to walk also in torque control, guaranteeing higher level of compliance. Real world experiments have been carried on the humanoid robot iCub.

Connected through hyperedge HE-1 (induced by source paper "whole body walking generation using contact parametrization a non linear trajectory optimization approach"):
  with members:
    - "a benchmarking of dcm based architectures for position and velocity controlled walking of humanoid robots"
    - "whole body nonlinear model predictive control through contacts for quadrupeds"
    - "simultaneous contact gait and motion planning for robust multi legged locomotion via mixed integer convex optimization"
    - "real time motion planning of legged robots a model predictive control approach"
    - "straight leg walking through underconstrained whole body control"
    - "a receding horizon push recovery strategy for balancing the icub humanoid robot"
    - "when to make a step tackling the timing problem in multi contact locomotion by topp mpc"
    - "trajectory generation for multi contact momentum control"

Connected through hyperedge HE-2 (induced by source paper "jerk control of floating base systems with contact stable parametrised force feedback"):
  with members:
    - "on line joint limit avoidance for torque controlled robots by joint space parametrization"

Connected through hyperedge HE-3 (induced by source paper "telexistence and teleoperation for walking humanoid robots"):
  with members:
    - "a benchmarking of dcm based architectures for position and velocity controlled walking of humanoid robots"
    - "a whole body software abstraction layer for control design of free floating mechanical systems"
    - "a review paper on oculus rift a virtual reality headset"

Connected through hyperedge HE-4 (induced by source paper "a benchmarking of dcm based architectures for position and velocity controlled walking of humanoid robots"):
  with members:
    - "trajectory generation for multi contact momentum control"

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)