Selected papers from ISRR'2019

This special issue is organized by selected papers presented at International Symposium on Robotics Research (ISRR 2019), held onOctober 6–10, 2019, at Hanoi, Vietnam. The conference enjoyed the distinguished talks by renowned invited speakers as well as active discussions at poster presentations of contributed papers on recent research. Following the strong relationship of the ISRR conferences with IJRR since its early years, the Program Chair and Co-Chairs proposed this special issue to the editorial board as guest editors and invited authors of contributed papers that received high review scores among many highquality papers to submit extended versions of the work. The guest editors would like to express their sincere gratitude to the authors for their patience by the review process that was slowed down due to the difficulties caused by the worldwide pandemic and are very delighted this special issue is finally complete. The special issue reflects the recent advancement of artificial intelligence and autonomy in different areas of robotics, but also includes the fundamental contributions that have been representing the tradition of ISRR, forming a good mixture covering broad areas of robotics research despite the small number of papers.While the conferencewas held 3 years back, we believe the special issue offers an excellent collection including updates with recent results. We have two papers that benefit from advanced research of artificial intelligence and autonomous agents especially useful for high-level planning. The first paper “Automatic Encoding and Repair of Reactive High-Level Tasks with Learned Abstract Representations” by Adam Pacheck, Steven James, George Konidaris, and Hadas Kress-Gazit presents skill-based framework enabling execution of reactive high-level tasks, by encoding robot skills with learned abstract sensor data to find a feasible plan for the task to be achieved. The second paper entitled “Multilevel Monte Carlo for Solving POMDPs Online” by Marcus Hoerger, Hanna Kurniawati, and Alberto Elfes addresses the challenging planning problem of Partially Observable Markov Decision Process (POMDP) with complex nonlinear dynamics, through an original approach of multi-level POMDP planner to obtain near-optimal solutions efficiently. The robotics fundamental contributions are about algorithmic foundation for manipulation and innovative robotics design and two papers are included for each topic. “The Blindfolded Traveler’s Problem: A Search Framework for Motion Planning with Contact Estimates" by Bradley Saund, Sanjiban Choudhury, Siddhartha Srinivasa, and Dmitry Berenson tackles planning on a graph containing unknown validity by novel policy-belief combination that expresses the collision probability and expert hypothesis about the collision at the same time. The secondmanipulation study is “The Certified Grasping” by Bernardo Aceituno-Cabezas, Jose Ballester, and Alberto Rodriguez. This paper proposes the idea of certificates to guarantee successful grasping, leading to convexcombinatorial formulation to derive optimal grasping of arbitrary planar objects. Regarding robotics design, “Joint Search of Optimal Topology and Trajectory for Planar Linkages” by Zherong Pan, Min Liu, Xifeng Gao, and Dinesh Manocha presents a new method for finding an optimal planar linkage such that the end-effector traces out a userdefined trajectory, based on optimization of both the robot node connection and link geometry. The other design paper “Versatile Articulated Aerial Robot DRAGON: Aerial Manipulation and Grasping by Vectorable Thrust Control” by Moju Zhao, Kei Okada, and Masauki Inaba demonstrates a unique aerial robot, composed of links with flying capacity, that can manipulate various objects by coordinated thrust control. The guest editors appreciate the reviewers for their constructive and insightful comments that greatly helped the authors improve their papers under unusual circumstances since 2020. We would also like to thank Prof. John Hollerbach and Antonio Bicchi for the opportunity to organize this special issue, Manish Nainwal and Sameer Grover for their support in editorial management, and the ISRR 2019 organizing committee for the cooperation in handling related information. We hope you have a pleasure of reading this special issue of The International Journal of Robotics Research dedicated to ISRR 2019. Special Issue Guest Editors