A Lightweight Modular Continuum Manipulator with IMU-based Force Estimation

Most aerial manipulators use serial rigid-link designs, which results in large forces when initiating contacts during manipulation and could cause flight stability difficulty. This limitation could potentially be improved by the compliance of continuum manipulators. To achieve this goal, we present the novel design of a compact, lightweight, and modular cable-driven continuum manipulator for aerial drones. We then derive a complete modeling framework for its kinematics, statics, and stiffness (compliance). The modeling framework can guide the control and design problems to integrate the manipulator to aerial drones. In addition, thanks to the derived stiffness (compliance) matrix, and using a low-cost IMU sensor to capture deformation angles, we present a simple method to estimate manipulation force at the tip of the manipulator. We report preliminary experimental validations of the hardware prototype, providing insights on its manipulation feasibility. We also report preliminary results of the IMU-based force estimation method.Comment: 12 pages, submitted to ASME Journal of Mechanisms and Robotics 2022, under review. arXiv admin note: substantial text overlap with arXiv:2206.0624

An Underactuated Flexible Instrument for Single Incision Laparoscopic Surgery

More and more patients and surgeons have switched from open surgery to minimally invasive surgery over these years. This exciting advancement has brought massive benefits to patients. Researchers and institutions have proposed robot assisted surgery which combines the advantage of developed robot system and human experience. This thesis reviews state of the art in this area and analyze some advanced surgical instrument for single incision laparoscopic instrument, then propose a design of robotic instrument for single incision laparoscopic surgery which can be integrated with collaborative robot manipulator to construct a surgical robot system.Single-incision laparoscopic surgery (SILS) has its own features and advantages compare to other minimally invasive surgery techniques which also lead to special design requirements for SILS instruments, among which increased flexibility compare to multi-incision surgery instruments is an important part. So we want to design a robotic surgical instrument that has increased flexibility compare to traditional instruments for other MIS techniques. As a laparoscopic robotic instrument compactness and light weight are also our considerations.Single incision laparoscopic surgery (SILS) inserts multiple instruments and laparoscopes through a single trocar which reduces trauma. But this improvement for patients caused difficulty in operation because of instruments triangulation, laparoscope field-of-view, etc. That brings up our challenges in designing a robotic instruments. Designing a highly flexible robotic instrument that provides sufficient workspace and good triangulation in order to relieve the difficulties introduced by narrow instrument trocars.We want to implement a highly recognized surgical instrument with a designed robotic instrument actuation pack. These two parts compose a robotic surgical instrument for single incision laparoscopic surgery. And we want to analyze the performance and viability of our design approach for SILS application

Wire-driven mechanism and highly efficient propulsion in water.

自然生物的杰出表现往往令人们叹为观止。正因为如此，在机器人研究中对自然界动植物的模仿从未间断。本文受动物肌肉骨骼系统（尤其是蛇的脊柱以及章鱼手臂的肌肉分布）的启发，设计了一种新型的仿生拉线机构。该机构由柔性骨架以及成对拉线组成。柔性骨架提供支撑，拉线模拟肌肉将驱动器的运动和力传递给骨架，并控制骨架运动。从骨架结构分，拉线机构可分为蛇形拉线机构以及连续型拉线机构；从骨架分段来看，拉线机构可分为单段式拉线机构以及多段式拉线机构，其中每段由一或两对拉线控制。拉线机构的主要性能特征包括：大柔性，高度欠驱动，杠杆效应，以及远程传力。机构的柔性使得它可以产生很大的弯曲变形；欠驱动设计极大地减少了驱动器的数目，简化了系统结构；在杠杆效应下，骨架末端速度、加速度与拉线的速度、加速度相比得到数十倍放大；通过拉线将驱动器的运动和力远程传递给执行机构，使得拉线机构结构简单紧凑。基于以上特征，拉线机构不仅适合工作于狭窄空间，同时也适合于摆动推进，尤其是水下推进。论文系统地介绍了拉线机构的设计，运动学，工作空间，静力学以及动力学模型。在常曲率假设下分别建立了蛇形拉线机构以及连续型拉线机构的运动学模型，在此基础上建立了一个通用运动学模型，以及工作空间模型。与传统避障相反，本文提出了一种利用现有障碍或主动布置约束来拓展工作空间的新方法。通过牛顿-欧拉法以及拉格朗日方程建立了蛇形拉线机构的静力学模型以及动力学模型。在非线性欧拉-伯努利梁理论下结合汉密尔顿原理建立了连续型拉线机构的静力学模型以及动力学模型。论文中利用拉线机构设计了一系列新型水下推进器。与传统机器鱼推进器设计方法（单关节，多关节以及基于智能材料的连续型设计）相比，基于拉线机构的水下推进器的优点在于：所需驱动器少，能更好地模拟鱼的游动，易于控制，推进效率高，以及容易衍生新型推进器。设计制作了四条拉线驱动机器鱼，以此为平台验证了拉线推进器的性能以及优点。实验结果表明，基于蛇形拉线机构的推进器可以提供较大推力；基于连续型拉线机构设计的推进器受摩擦影响较小；基于单段式拉线机构的推进器可以模仿鱼类摆动式推进，具有很好的转弯性能；基于多段式拉线机构的推进器可以同时模仿摆动式推进和波动式推进，具有更好的稳定性以及游速。此外，基于拉线机构制造了一种新型矢量推进器。该推进器可以提供任意方向的推力，从而提高机器鱼的机动性能。实验中，在两个额定功率为1瓦的电机驱动下，机器鱼的最大游速为0.67 体长/秒；最小转弯半径为0.24倍体长；转弯速度为51.4 度/秒；最高推进效率为92.85%。最后，采用拉线推进器制作了一个室内空中移动机器人，取名为Flying Octopus。它由一个氦气球提供浮力悬停在空中，通过四个独立控制的拉线扑翼驱动可在三维空间自由运动。Attracted by the outstanding performance of natural creatures, researchers have been mimicking animals and plants to develop their robots. Inspired by animals’ musculoskeletal system, especially the skeletal structure of snakes and octopus arm muscle arrangement, in this thesis, a novel wire-driven mechanism (WDM) is designed. It is composed of a flexible backbone and a number of controlling wire groups. The flexible backbone provides support, while the wire groups transmit motion and force from the actuators, mimicking the muscles. According to its backbone structure, the WDM is categorized as serpentine WDM and continuum WDM. Depending on the backbone segmentation, WDM is divided into single segment WDM and multi-segment WDM. Each segment is controlled by one or two wire groups. Features of WDM include: flexible, highly under-actuated, leverage effect, and long range force and motion transmission. The flexibility enables the WDM making large deformation, while the under-actuation greatly reduces th number of actuators, simplifying the system. With the leverage effect, WDM distal end velocity and acceleration is greatly amplified from that of wire. Also, in the WDM, the actuators and the backbone are serperated. Actuator’s motion is transmitted by the wires. This makes the WDM very compact. With these features, the WDM is not only well suited to confined space, but also flapping propulsion, especially in water.In the thesis, the design, kinematics, workspace, static and dynamic models of the WDM are explored systematically. Under the constant curvature assumption, the kinematic model of serpentine WDM and continuum WDM are established. A generalized model is also developed. Workspace model is built from the forward kinematic model. Rather than avoiding obstacles, a novel idea of employing obstacles or actively deploying constraints to expand workspace is also discussed for WDM-based flexible manipulators. The static model and dynamic model of serpentine WDM is developed using the Newton-Euler method and the Lagrange Equation, while that of continuum WDM is built under the non-linear Euler-Bernoulli Beam theory and the extended Hamilton’s principle.In the thesis, a number of novel WDM based underwater propulsors are developed. Compared with existing fish-like propulsor designs, including single joint design, multi-joint design, and smart material based continuum design, the proposed WDM-based propulsors have advantages in several aspects, such as employing less actuators, better resembling the fish swimming body curve, ease of control, and more importantly, being highly efficient. Also, brand new propulsors can be easily developed using the WDM. To demonstrate the features as well as the advantages of WDM propulsors, four robot fish prototypes are developed. Experiments show that the serpentine WDM-based propulsor could provide large flapping force while the continuum WDM-based propulsor is less affected by joint friction. On the other hand, single segment WDM propulsor can make oscillatory swim while multi- segment WDM propulsor can make both oscillatory and undulatory swims. The undulatory swimming outperforms the oscillatory swimming in stability and speed, but is inferior in turning around. In addition, a novel robot fish with vector propulsion capability is also developed. It can provide thrust in arbitrary directions, hence, improving the maneuverability of the robot fish. In the experiments, with the power limit of two watts, the maximum forward speed of the WDM robot fishes can reach 0.67 BL (Body Length)/s. The minimum turning radius is 0.24 BL, and the turning speed is 51.4°/s. The maximum Froude efficiency of the WDM robot fishes is 92.85%. Finally, the WDM-based propulsor is used to build an indoor Lighter-than-Air- Vehicle (LTAV), named Flying Octopus. It is suspended in the air by a helium balloon and actuated by four independently controlled wire-driven flapping wings. With the wing propulsion, it can move in 3D space effectively.Detailed summary in vernacular field only.Detailed summary in vernacular field only.Detailed summary in vernacular field only.Li, Zheng.Thesis (Ph.D.)--Chinese University of Hong Kong, 2013.Includes bibliographical references (leaves 205-214).Abstracts also in Chinese.Abstracth --- p.i摘要 --- p.iiiAcknowledgement --- p.vList of Figures --- p.xiList of Tables --- p.xviiChapter Chapter 1 --- Introduction --- p.1Chapter 1.1 --- Background --- p.1Chapter 1.2 --- Related Research --- p.2Chapter 1.2.1 --- Flexible Manipulator --- p.2Chapter 1.2.2 --- Robot Fish --- p.10Chapter 1.3 --- Motivation of the Dissertation --- p.13Chapter 1.4 --- Organization of the Dissertation --- p.14Chapter Chapter 2 --- Biomimetic Wire-Driven Mechanism --- p.16Chapter 2.1 --- Inspiration from Nature --- p.16Chapter 2.1.1 --- Snake Skeleton --- p.18Chapter 2.1.2 --- Octopus Arm --- p.19Chapter 2.2 --- Wire-Driven Mechanism Design --- p.20Chapter 2.2.1 --- Flexible Backbone --- p.20Chapter 2.2.2 --- Backbone Segmentation --- p.26Chapter 2.2.3 --- Wire Configuration --- p.28Chapter 2.3 --- Wire-Driven Mechanism Categorization --- p.31Chapter 2.4 --- Summary --- p.32Chapter Chapter 3 --- Kinematics and Workspace of the Wire-Driven Mechanism --- p.33Chapter 3.1 --- Kinematic Model of Single Segment WDM --- p.33Chapter 3.1.1 --- Kinematic Model of the Serpentine WDM --- p.34Chapter 3.1.2 --- Kinematic Model of the Continuum WDM --- p.39Chapter 3.1.3 --- A Generalized Kinematic Model --- p.43Chapter 3.2 --- Kinematic Model of Multi-Segment WDM --- p.47Chapter 3.2.1 --- Forward Kinematics --- p.47Chapter 3.2.2 --- Inverse Kinematics --- p.51Chapter 3.3 --- Workspace --- p.52Chapter 3.3.1 --- Workspace of Single Segment WDM --- p.52Chapter 3.3.2 --- Workspace of Multi-Segment WDM --- p.53Chapter 3.4 --- Employing Obstacles to Expand WDM Workspace --- p.55Chapter 3.4.1 --- Constrained Kinematics Model of WDM --- p.55Chapter 3.4.2 --- WDM Workspace with Constraints --- p.61Chapter 3.5 --- Model Validation via Experiment --- p.64Chapter 3.5.1 --- Single Segment WDM Kinematic Model Validation --- p.64Chapter 3.5.2 --- Multi-Segment WDM Kinematic Model Validation --- p.66Chapter 3.5.3 --- Constrained Kinematic Model Validation --- p.70Chapter 3.6 --- Summary --- p.73Chapter Chapter 4 --- Statics and Dynamics of the Wire-Driven Mechanism --- p.75Chapter 4.1 --- Static Model of the Wire-Driven Mechanism --- p.75Chapter 4.1.1 --- Static Model of SPSP WDM --- p.75Chapter 4.1.2 --- Static Model of SPCP WDM --- p.81Chapter 4.2 --- Dynamic Model of the Wire-Driven Mechanism --- p.88Chapter 4.2.1 --- Dynamic Model of SPSP WDM --- p.88Chapter 4.2.2 --- Dynamic Model of SPCP WDM --- p.92Chapter 4.3 --- Summary --- p.94Chapter Chapter 5 --- Application I - Wire-Driven Robot Fish --- p.95Chapter 5.1 --- Fish Swimming Introduction --- p.95Chapter 5.1.1 --- Fish Swimming Categories --- p.95Chapter 5.1.2 --- Body Curve Function --- p.96Chapter 5.1.3 --- Fish Swimming Hydrodynamics --- p.101Chapter 5.1.4 --- Fish Swimming Data --- p.103Chapter 5.2 --- Oscillatory Wire-Driven Robot Fish --- p.104Chapter 5.2.1 --- Serpentine Oscillatory Wire-Driven Robot Fish Design --- p.105Chapter 5.2.2 --- Continuum Oscillatory Wire-Driven Robot Fish Design --- p.110Chapter 5.2.3 --- Oscillatory Robot Fish Propulsion Model --- p.114Chapter 5.2.4 --- Robot Fish Swimming Control --- p.116Chapter 5.2.5 --- Swimming Experiments --- p.118Chapter 5.3 --- Undulatory Wire-Driven Robot Fish --- p.125Chapter 5.3.1 --- Undulatory Wire-Driven Robot Fish Design --- p.125Chapter 5.3.2 --- Undulatory Wire-Driven Robot Fish Propulsion Model --- p.130Chapter 5.3.3 --- Swimming Experiments --- p.131Chapter 5.4 --- Vector Propelled Wire-Driven Robot Fish --- p.136Chapter 5.4.1 --- Vector Propelled Wire-Driven Robot Fish Design --- p.136Chapter 5.4.2 --- Tail Motion Analysis --- p.140Chapter 5.4.3 --- Swimming Experiments --- p.142Chapter 5.5 --- Wire-Driven Robot Fish Performance and Discussion --- p.144Chapter 5.5.1 --- Performance --- p.144Chapter 5.5.2 --- Discussion --- p.147Chapter 5.6 --- Summary --- p.149Chapter Chapter 6 --- Aplication II - Wire-Driven LTAV - Flying Octopus --- p.151Chapter 6.1 --- Introduction --- p.151Chapter 6.2 --- Flying Octopus Design --- p.152Chapter 6.2.1 --- Flying Octopus Body Design --- p.152Chapter 6.2.2 --- Wire-Driven Flapping Wing Design --- p.153Chapter 6.3 --- Flying Octopus Motion Control --- p.156Chapter 6.3.1 --- Propulsion Model --- p.156Chapter 6.3.2 --- Motion Control Strategy --- p.157Chapter 6.3.3 --- Motion Simulation --- p.159Chapter 6.4 --- Prototype and Indoor Experiments --- p.161Chapter 6.4.1 --- Flying Octopus Prototype --- p.161Chapter 6.4.2 --- Indoor Experiments --- p.163Chapter 6.4.3 --- Discussion --- p.165Chapter 6.5 --- Summary --- p.166Chapter Chapter 7 --- Conclusions and Future Work --- p.167Chapter Appendix A - --- Publication Record --- p.170Chapter Appendix B - --- Derivation --- p.172Chapter Appendix C --- Matlab Programs --- p.176References --- p.20

CABLE DECOUPLING AND CABLE-BASED STIFFENING OF CONTINUUM ROBOTS

Cable-driven continuum robots, which are robots with a continuously flexible backbone and no identifiable joints that are actuated by cables, have shown great potential for many applications in unstructured, uncertain environments. However, the standard design for a cable-driven continuum robot segment, which bends a continuous backbone along a circular arc, has many compliant modes of deformation which are uncontrolled, and which may result in buckling or other undesirable behaviors if not ameliorated. In this study, a detailed approach for using additional cables to selectively stiffen planar cable-driven robots without substantial coupling to the actuating cables is investigated. A mechanics-based model based on the planar Cosserat equations is used to find the design conditions under which additional cables can be routed without coupling of the cable lengths for small deformations. Simulations show that even for relatively large deformations, coupling remains small. A prototype was designed and evaluated, and it was demonstrated that the compliance of the robot is substantially modified relative to the same robot without the additional stiffening cables. The additional stiffening cables are shown to increase the end-effector output stiffness by a factor of approximately 10 over a typical design with actuating cables

Improving Strength and Stability in Continuum Robots

Continuum robots, which are bio-inspired ’trunk-like’ robots, are characterized for their inherent compliance and range of motion. One of the key challenges in continuum robotics research is developing robots with sufficient strength and stability without adding additional weight or complexity to the design. The research conducted in this dissertation encompasses design and modeling strategies that address these challenges in strength and stability. This work improves three continuum robot actuation paradigms: (1) tendon-driven continuum robots (TDCR), (2) concentric tube robots (CTR), and (3) concentric push-pull robots (CPPR). The first chapter of contribution covers strategies for improving strength in TDCRs. The payload capacity and torsional stiffness of the robot can be improved by leveraging the geometry of the backbone design and tendon routing, with design choices experimentally validated on a robot prototype. The second chapter covers a new bending actuator, concentric precurved bellows (CPB), that are based upon CTR actuation. The high torsional stiffness of bellows geometry virtually eliminates the torsional compliance instability found in CTRs. Two bellows designs are developed for 3D printing and the mechanical properties of these designs are characterized through experiments on prototypes and in static finite element analysis. A torsionally rigid kinematic model is derived and validated on 3D printed prototypes. The third chapter of contribution covers the development and validation of a mechanics-based CPPR kinematics model. CPPRs are constructed from concentrically nested, asymmetrically patterned tubes that are fixed together at their distal tips. Relative translations between the tubes induces bending shapes from the robot. The model expands the possible design space of CPPRs by enabling the modeling of external loads, non-planar bending shapes, and CPPRs with more than two tubes. The model is validated on prototypes in loaded and unloaded experiments

Pattern recognition-based real-time myoelectric control for anthropomorphic robotic systems : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Mechatronics at Massey University, Manawatū, New Zealand

All copyrighted Figures have been removed but may be accessed via their source cited in their respective captions.Advanced human-computer interaction (HCI) or human-machine interaction (HMI) aims to help humans interact with computers smartly. Biosignal-based technology is one of the most promising approaches in developing intelligent HCI systems. As a means of convenient and non-invasive biosignal-based intelligent control, myoelectric control identifies human movement intentions from electromyogram (EMG) signals recorded on muscles to realise intelligent control of robotic systems. Although the history of myoelectric control research has been more than half a century, commercial myoelectric-controlled devices are still mostly based on those early threshold-based methods. The emerging pattern recognition-based myoelectric control has remained an active research topic in laboratories because of insufficient reliability and robustness. This research focuses on pattern recognition-based myoelectric control. Up to now, most of effort in pattern recognition-based myoelectric control research has been invested in improving EMG pattern classification accuracy. However, high classification accuracy cannot directly lead to high controllability and usability for EMG-driven systems. This suggests that a complete system that is composed of relevant modules, including EMG acquisition, pattern recognition-based gesture discrimination, output equipment and its controller, is desirable and helpful as a developing and validating platform that is able to closely emulate real-world situations to promote research in myoelectric control. This research aims at investigating feasible and effective EMG signal processing and pattern recognition methods to extract useful information contained in EMG signals to establish an intelligent, compact and economical biosignal-based robotic control system. The research work includes in-depth study on existing pattern recognition-based methodologies, investigation on effective EMG signal capturing and data processing, EMG-based control system development, and anthropomorphic robotic hand design. The contributions of this research are mainly in following three aspects: Developed precision electronic surface EMG (sEMG) acquisition methods that are able to collect high quality sEMG signals. The first method was designed in a single-ended signalling manner by using monolithic instrumentation amplifiers to determine and evaluate the analog sEMG signal processing chain architecture and circuit parameters. This method was then evolved into a fully differential analog sEMG detection and collection method that uses common commercial electronic components to implement all analog sEMG amplification and filtering stages in a fully differential way. The proposed fully differential sEMG detection and collection method is capable of offering a higher signal-to-noise ratio in noisy environments than the single-ended method by making full use of inherent common-mode noise rejection capability of balanced signalling. To the best of my knowledge, the literature study has not found similar methods that implement the entire analog sEMG amplification and filtering chain in a fully differential way by using common commercial electronic components. Investigated and developed a reliable EMG pattern recognition-based real-time gesture discrimination approach. Necessary functional modules for real-time gesture discrimination were identified and implemented using appropriate algorithms. Special attention was paid to the investigation and comparison of representative features and classifiers for improving accuracy and robustness. A novel EMG feature set was proposed to improve the performance of EMG pattern recognition. Designed an anthropomorphic robotic hand construction methodology for myoelectric control validation on a physical platform similar to in real-world situations. The natural anatomical structure of the human hand was imitated to kinematically model the robotic hand. The proposed robotic hand is a highly underactuated mechanism, featuring 14 degrees of freedom and three degrees of actuation. This research carried out an in-depth investigation into EMG data acquisition and EMG signal pattern recognition. A series of experiments were conducted in EMG signal processing and system development. The final myoelectric-controlled robotic hand system and the system testing confirmed the effectiveness of the proposed methods for surface EMG acquisition and human hand gesture discrimination. To verify and demonstrate the proposed myoelectric control system, real-time tests were conducted onto the anthropomorphic prototype robotic hand. Currently, the system is able to identify five patterns in real time, including hand open, hand close, wrist flexion, wrist extension and the rest state. With more motion patterns added in, this system has the potential to identify more hand movements. The research has generated a few journal and international conference publications

Wearable haptic systems for the fingertip and the hand: taxonomy, review and perspectives

In the last decade, we have witnessed a drastic change in the form factor of audio and vision technologies, from heavy and grounded machines to lightweight devices that naturally fit our bodies. However, only recently, haptic systems have started to be designed with wearability in mind. The wearability of haptic systems enables novel forms of communication, cooperation, and integration between humans and machines. Wearable haptic interfaces are capable of communicating with the human wearers during their interaction with the environment they share, in a natural and yet private way. This paper presents a taxonomy and review of wearable haptic systems for the fingertip and the hand, focusing on those systems directly addressing wearability challenges. The paper also discusses the main technological and design challenges for the development of wearable haptic interfaces, and it reports on the future perspectives of the field. Finally, the paper includes two tables summarizing the characteristics and features of the most representative wearable haptic systems for the fingertip and the hand

Design, modeling and implementation of a soft robotic neck for humanoid robots

Mención Internacional en el título de doctorSoft humanoid robotics is an emerging field that combines the flexibility and safety of soft robotics with the form and functionality of humanoid robotics. This thesis explores the potential for collaboration between these two fields with a focus on the development of soft joints for the humanoid robot TEO. The aim is to improve the robot’s adaptability and movement, which are essential for an efficient interaction with its environment. The research described in this thesis involves the development of a simple and easily transportable soft robotic neck for the robot, based on a 2 Degree of Freedom (DOF) Cable Driven Parallel Mechanism (CDPM). For its final integration into TEO, the proposed design is later refined, resulting in an efficiently scaled prototype able to face significant payloads. The nonlinear behaviour of the joints, due mainly to the elastic nature of their soft links, makes their modeling a challenging issue, which is addressed in this thesis from two perspectives: first, the direct and inverse kinematic models of the soft joints are analytically studied, based on CDPM mathematical models; second, a data-driven system identification is performed based on machine learning techniques. Both approaches are deeply studied and compared, both in simulation and experimentally. In addition to the soft neck, this thesis also addresses the design and prototyping of a soft arm capable of handling external loads. The proposed design is also tendon-driven and has a morphology with two main bending configurations, which provides more versatility compared to the soft neck. In summary, this work contributes to the growing field of soft humanoid robotics through the development of soft joints and their application to the humanoid robot TEO, showcasing the potential of soft robotics to improve the adaptability, flexibility, and safety of humanoid robots. The development of these soft joints is a significant achievement and the research presented in this thesis paves the way for further exploration and development in this field.La robótica humanoide blanda es un campo emergente que combina la flexibilidad y seguridad de la robótica blanda con la forma y funcionalidad de la robótica humanoide. Esta tesis explora el potencial de colaboración entre estos dos campos centrándose en el desarrollo de una articulación blanda para el cuello del robot humanoide TEO. El objetivo es mejorar la adaptabilidad y el movimiento del robot, esenciales para una interacción eficaz con su entorno. La investigación descrita en esta tesis consiste en el desarrollo de un prototipo sencillo y fácilmente transportable de cuello blando para el robot, basado en un mecanismo paralelo actuado por cable de 2 grados de libertad. Para su integración final en TEO, el diseño propuesto es posteriormente refinado, resultando en un prototipo eficientemente escalado capaz de manejar cargas significativas. El comportamiemto no lineal de estas articulaciones, debido fundamentalmente a la naturaleza elástica de sus eslabones blandos, hacen de su modelado un gran reto, que en esta tesis se aborda desde dos perspectivas diferentes: primero, los modelos cinemáticos directo e inverso de las articulaciones blandas se estudian analíticamente, basándose en modelos matemáticos de mecanismos paralelos actuados por cable; segundo, se aborda el problema de la identificación del sistema mediante técnicas basadas en machine learning. Ambas propuestas se estudian y comparan en profundidad, tanto en simulación como experimentalmente. Además del cuello blando, esta tesis también aborda el diseño de un brazo robótico blando capaz de manejar cargas externas. El diseño propuesto está igualmente basado en accionamiento por tendones y tiene una morfología con dos configuraciones principales de flexión, lo que proporciona una mayor versatilidad en comparación con el cuello robótico blando. En resumen, este trabajo contribuye al creciente campo de la robótica humanoide blanda mediante el desarrollo de articulaciones blandas y su aplicación al robot humanoide TEO, mostrando el potencial de la robótica blanda para mejorar la adaptabilidad, flexibilidad y seguridad de los robots humanoides. El desarrollo de estas articulaciones es una contribución significativa y la investigación presentada en esta tesis allana el camino hacia nuevos desarrollos y retos en este campo.Programa de Doctorado en Ingeniería Eléctrica, Electrónica y Automática por la Universidad Carlos III de MadridPresidenta: Cecilia Elisabet García Cena.- Secretario: Dorin Sabin Copaci.- Vocal: Martin Fodstad Stole

Kinematics and Robot Design II (KaRD2019) and III (KaRD2020)

This volume collects papers published in two Special Issues “Kinematics and Robot Design II, KaRD2019” (https://www.mdpi.com/journal/robotics/special_issues/KRD2019) and “Kinematics and Robot Design III, KaRD2020” (https://www.mdpi.com/journal/robotics/special_issues/KaRD2020), which are the second and third issues of the KaRD Special Issue series hosted by the open access journal robotics.The KaRD series is an open environment where researchers present their works and discuss all topics focused on the many aspects that involve kinematics in the design of robotic/automatic systems. It aims at being an established reference for researchers in the field as other serial international conferences/publications are. Even though the KaRD series publishes one Special Issue per year, all the received papers are peer-reviewed as soon as they are submitted and, if accepted, they are immediately published in MDPI Robotics. Kinematics is so intimately related to the design of robotic/automatic systems that the admitted topics of the KaRD series practically cover all the subjects normally present in well-established international conferences on “mechanisms and robotics”.KaRD2019 together with KaRD2020 received 22 papers and, after the peer-review process, accepted only 17 papers. The accepted papers cover problems related to theoretical/computational kinematics, to biomedical engineering and to other design/applicative aspects