Design, Control, and Motion Strategy of TRADY: Tilted-Rotor-Equipped Aerial Robot With Autonomous In-Flight Assembly and Disassembly Ability

In previous research, various types of aerial robots were developed to improve maneuverability or manipulation abilities. However, there was a challenge in achieving both mobility and manipulation capabilities simultaneously. This is because aerial robots with high mobility lack the necessary rotors to perform manipulation tasks, while those with manipulation ability are too large to achieve high mobility. To address this issue, a new aerial robot called TRADY was introduced in this article. TRADY is a tilted-rotor-equipped aerial robot that can autonomously assemble and disassemble in-flight, allowing for a switch in control model between under-actuated and fully-actuated models. The system features a novel docking mechanism and optimized rotor configuration, as well as a control system that can transition between under-actuated and fully-actuated modes and compensate for discrete changes. Additionally, a new motion strategy for assembly/disassembly motion that includes recovery behavior from hazardous conditions was introduced. Experimental results showed that TRADY can successfully execute aerial assembly/disassembly motions with a 90% success rate and generate more than nine times the torque of a single unit in the assembly state. This is the first robot system capable of performing both assembly and disassembly while seamlessly transitioning between fully-actuated and under-actuated models

Versatile Multilinked Aerial Robot with Tilting Propellers: Design, Modeling, Control and State Estimation for Autonomous Flight and Manipulation

Multilinked aerial robot is one of the state-of-the-art works in aerial robotics, which demonstrates the deformability benefiting both maneuvering and manipulation. However, the performance in outdoor physical world has not yet been evaluated because of the weakness in the controllability and the lack of the state estimation for autonomous flight. Thus we adopt tilting propellers to enhance the controllability. The related design, modeling and control method are developed in this work to enable the stable hovering and deformation. Furthermore, the state estimation which involves the time synchronization between sensors and the multilinked kinematics is also presented in this work to enable the fully autonomous flight in the outdoor environment. Various autonomous outdoor experiments, including the fast maneuvering for interception with target, object grasping for delivery, and blanket manipulation for firefighting are performed to evaluate the feasibility and versatility of the proposed robot platform. To the best of our knowledge, this is the first study for the multilinked aerial robot to achieve the fully autonomous flight and the manipulation task in outdoor environment. We also applied our platform in all challenges of the 2020 Mohammed Bin Zayed International Robotics Competition, and ranked third place in Challenge 1 and sixth place in Challenge 3 internationally, demonstrating the reliable flight performance in the fields

Generalized Design, Modeling and Control Methodology for a Snake-like Aerial Robot

Snake-like robots have been developing in recent decades, and various bio-inspired ideas are deployed in both the mechanical and locomotion aspects. In recent years, several studies have proposed state-of-the-art snake-like aerial robots, which are beyond bio-inspiration. The achievement of snake-like aerial robots benefits both aerial maneuvering and manipulation, thereby having importance in various fields, such as industry surveillance and disaster rescue. In this work, we introduce our development of the modular aerial robot which can be considered a snake-like robot with high maneuverability in flight. To achieve such flight, we first proposed a unique thrust vectoring apparatus equipped with dual rotors to enable three-dimensional thrust force. Then, a generalized modeling method based on dynamics approximation is proposed to allocate the wrench in the center-of-gravity (CoG) frame to thrust forces and vectoring angles. We further developed a generalized control framework that can handle both under-actuated and fully actuated models. Finally, we show the experimental results with two different platforms to evaluate the flight stability of the proposed snake-like aerial robot. We believe that the proposed generalized methods can provide a solid foundation for the snake-like aerial robot and its applications regarding maneuvering and manipulation in midair

ロータ分散型飛行マニピュレータにおける壁面近接行動制御と動作実現の研究

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 稲葉 雅幸, 東京大学教授 國吉 康夫, 東京大学教授 苗村 健, 東京大学教授 深尾 隆則, 東京大学教授 岡田