磁性流体を用いたバックドライブ可能な油圧アクチュエータの開発

早大学位記番号:新7478早稲田大

Développement d'une unité de valves motorisées et algorithme de transition pour actionnement hydrostatique bimodal d'une jambe robotique

Les robots mobiles, tels que les exosquelettes et les robots marcheurs, utilisent des actionneurs qui doivent satisfaire à une large plage de requis de force et de vitesse. Par exemple, pour le cycle de marche d’une jambe robotique, la phase d’appui nécessite une force élevée tandis que la phase de balancement requiert une grande vitesse. Pour satisfaire ces requis opposés, le dimensionnement d’un système d’actionnement traditionnel à rapport de réduction unique conduit généralement à un moteur électrique lourd, surdimensionné et à une faible efficacité énergétique. Ainsi, l’alternative explorée est une architecture hydrostatique à deux vitesses où des valves motorisées sont utilisées pour reconfigurer dynamiquement le système entre deux modes de fonctionnement : fort ou rapide. La complexité réside dans le choix d’une technologie de valve légère ainsi que dans le développement d’un algorithme de contrôle permettant de réaliser les transitions de manière rapide et fluide. Un prototype d’une unité de valves motorisées est conçu et intégré dans l’architecture hydrostatique complète de l’actionneur et un banc d’essai d’une jambe robotique est fabriqué. Trois stratégies de contrôle des moteurs sont comparées lors du changement de mode : une vitesse constante, une diminution de vitesse et une réduction du courant. La méthode choisie, le contrôle en courant, est ensuite utilisée pour la démonstration des phases d’appui et de balancement de la jambe robotique. Par cette méthode, il est possible d’effectuer des transitions rapides, de maintenir une force suffisante et de minimiser les oscillations qui surviennent lors du contact avec le sol. Ces travaux offrent donc un premier point de comparaison au niveau du choix de valves, de la masse, de la vitesse d’actionnement et de la stratégie de contrôle

Development of a knee prosthesis powered by electro-hydrostatic actuation

L'abstract è presente nell'allegato / the abstract is in the attachmen

Review of Development Stages in the Conceptual Design of an Electro Hydrostatic Actuator for Robotics

The design of modern robotic devices faces numerous requirements and limitations which are related to optimization and robustness. Consequently, these stringent requirements have caused improvements in many engineering areas and lead to development of new optimization methods which better handle new complex products designed for application in industrial robots. One of the newly developed methods used in industrial robotics is the concept of a self-contained power device, an Electro-Hydrostatic Actuator (EHA). EHA devices were designed with a central idea, to avoid the possible drawbacks which were present in other types of actuators that are currently used in robotic systems. This paper is a review of the development phases of an EHA device for robotic applications. An overview of the advantages and disadvantages related to current EHA designs are presented, and finally possible ideas for future developments are suggested

DESIGN AND CHARACTERISATION OF A CONTINUOUS ROTARY DAMPER WITH IDEAL VISCOUS DAMPING PROPERTIES

Master'sMASTER OF ENGINEERIN

Electromechanical Performance of HASEL Actuators: Fundamentals and Applications

Soft robotic systems are well-suited to unstructured, dynamic tasks and environments, but are currently limited by the soft actuators that power them. Most current soft actuators are based on pneumatics or shape-memory alloys, which have issues with efficiency, response speed, and portability. More recently, dielectric elastomer actuators (DEAs) have shown promise, but they have limited material selection, fabrication methods, and modes of actuation. As such, there remains a need for new types of high performance and well-rounded soft actuators. This dissertation focuses on the development and exploration of a new class of soft electrohydraulic actuators called hydraulically amplified self-healing electrostatic (HASEL) actuators. The first part of this dissertation (Chapter 2) presents of a subclass of HASEL actuators called Peano-HASELs that simultaneously introduce a breakthrough materials system based on thermoplastic films as well as a novel contractile mode of actuation. This approach enables industrially-amenable fabrication techniques, vastly expands the usable materials for actuator construction, and results in high performance actuators with fast linear contraction on activation. The second part of this dissertation (Chapter 3) elucidates the fundamentals of the electromechanical coupling that drives HASEL actuators. An analytical model is developed that accurately describes the quasi-static actuation behavior of Peano-HASEL actuators without relying on fitting parameters. Using this model, we identify a theory-driven approach to actuator design, including a roadmap for actuators with drastically improved specific energies. The final section of this dissertation (Chapter 4 and 5) looks towards more integrated and applied designs of HASEL actuators. First, a new type of articulating actuator is presented that integrates both compliant and rigid components. These spider-inspired electrohydraulic soft-actuated (SES) joints demonstrate high torque and high-speed actuation in an independently-addressable multi-joint limb, a bidirectional actuator, and a versatile gripper. Second, a biodegradable materials system is presented for high performance Peano-HASEL actuators that reduce environmental impact. Finally, a new method of capacitive self-sensing is presented that enables inexpensive and compact circuits that use only off-the-shelf and low voltage components. The results presented in this dissertation provide a framework for the development of high-performance actuators that may one day power the next generation of capable soft robots.</p

Robotics 2010

Without a doubt, robotics has made an incredible progress over the last decades. The vision of developing, designing and creating technical systems that help humans to achieve hard and complex tasks, has intelligently led to an incredible variety of solutions. There are barely technical fields that could exhibit more interdisciplinary interconnections like robotics. This fact is generated by highly complex challenges imposed by robotic systems, especially the requirement on intelligent and autonomous operation. This book tries to give an insight into the evolutionary process that takes place in robotics. It provides articles covering a wide range of this exciting area. The progress of technical challenges and concepts may illuminate the relationship between developments that seem to be completely different at first sight. The robotics remains an exciting scientific and engineering field. The community looks optimistically ahead and also looks forward for the future challenges and new development

Neural Extended Kalman Filter for State Estimation of Automated Guided Vehicle in Manufacturing Environment

To navigate autonomously in a manufacturing environment Automated Guided Vehicle (AGV) needs the ability to infer its pose. This paper presents the implementation of the Extended Kalman Filter (EKF) coupled with a feedforward neural network for the Visual Simultaneous Localization and Mapping (VSLAM). The neural extended Kalman filter (NEKF) is applied on-line to model error between real and estimated robot motion. Implementation of the NEKF is achieved by using mobile robot, an experimental environment and a simple camera. By introducing neural network into the EKF estimation procedure, the quality of performance can be improved

Prediction of Robot Execution Failures Using Neural Networks

In recent years, the industrial robotic systems are designed with abilities to adapt and to learn in a structured or unstructured environment. They are able to predict and to react to the undesirable and uncontrollable disturbances which frequently interfere in mission accomplishment. In order to prevent system failure and/or unwanted robot behaviour, various techniques have been addressed. In this study, a novel approach based on the neural networks (NNs) is employed for prediction of robot execution failures. The training and testing dataset used in the experiment consists of forces and torques memorized immediately after the real robot failed in assignment execution. Two types of networks are utilized in order to find best prediction method - recurrent NNs and feedforward NNs. Moreover, we investigated 24 neural architectures implemented in Matlab software package. The experimental results confirm that this approach can be successfully applied to the failures prediction problem, and that the NNs outperform other artificial intelligence techniques in this domain. To further validate a novel method, real world experiments are conducted on a Khepera II mobile robot in an indoor structured environment. The obtained results for trajectory tracking problem proved usefulness and the applicability of the proposed solution