Proc. IEEE/RSJ Int. Conf. Intell. Rob. Syst. Proc. IEEE/RSJ Int. Conf. Intell. Rob. Syst. Finding safe 3D robot grasps through efficient haptic exploration with unscented Bayesian optimization and collision penalty Castanheira Joao Vicente Pedro Martinez Cantin Ruben Universidad de Zaragoza Jamone Lorenzo Bernardino Alexandre 2019 research-article