serial and parallel robotics: energy saving systems and rehabilitation devices

This thesis focuses on the design and discussion of robotic devices and their applications. Robotics is the branch of technology that deals with the design, construction, operation, and application of robots as well as computer systems for their control, sensory feedback, and information processing [1]. Nowadays, robotics has been an unprecedented increase in applications of industry, military, health, domestic service, exploration, commerce, etc. Different applications require robots with different structures and different functions. Robotics normally includes serial and parallel structures. To have contribution to two kinds of structures, this thesis consisting of two sections is devoted to the design and development of serial and parallel robotic structures, focused on applications in the two different fields: industry and health

Design of a mechatronic system for postural control analysis

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

Principles of Small-Scale Hydraulic Systems for Human Assistive Machines

University of Minnesota Ph.D. dissertation. March 2017. Major: Mechanical Engineering. Advisor: William Durfee. 1 computer file (PDF); xiii, 288 pages.The high power and force density of hydraulic actuators, along with the ability to distribute system weight through the separation of the power supply and actuators makes hydraulic technology ideal for use in human assistive machines. However, hydraulic systems often operate inefficiently due to throttling losses in the control valves and have increased viscous losses in small-scale applications as bore size is decreased. The objective of this research is to address the limitations of small-scale hydraulics using validated modeling techniques to optimize performance and minimize system weight. This research compares and contrasts the use of different hydraulic technology as well as develops detailed models of small-scale hydraulic components. These models are used to construct a software tool that optimizes the design of a hydraulic system using specified input requirements of actuation, conduit lengths, operating pressure, and runtime. A system-level energetics analysis provides estimates of efficiencies and weights, while a heat transfer analysis estimates the working fluid and component surface temperatures. In addition, the dynamic performance of different small-scale pump and valve controlled hydraulic systems are simulated to compare the cycle efficiencies, rise times, and flow rate capabilities as a function of duty cycles. The use of an accumulator, unloading valves, variable displacement pumps, and proportional pressure control are explored to improve the efficiency of the system during intermittent operation. In addition a small-scale, digital, high frequency switching valve is designed and simulated to reduce the throttling losses of a traditional proportional control valve. This body of knowledge is used to design, prototype, and performance test two hydraulic powered ankle-foot orthoses. The first orthosis is an untethered system that provides active gait assistance. Hydraulics allows the system to be separated into two parts as the actuator is secured to the ankle, and the portable electrohydraulic power supply is positioned on the lower back. The second orthosis emulates the dynamics of a passive ankle-foot orthosis providing torque assistance to bring the ankle to a neutral position. This device is specifically designed to reduce the time and resources in the clinical prescription of passive ankle-foot orthoses while providing more quantitative metrics

A methodology for the Lower Limb Robotic Rehabilitation system

The overall goal of this thesis is to develop a new functional lower limb robot-assisted rehabilitation system for people with a paretic lower limb. A unilateral rehabilitation method is investigated, where the robot acts as an assistive device to provide the impaired leg therapeutic training through simulating the kinematics and dynamics of the ankle and lower leg movements. Foot trajectories of healthy subjects and post-stroke patients were recorded by a dedicated optical motion tracking system in a clinical gait measurement laboratory. A prototype 6 degrees of freedom parallel robot was initially built in order to verify capability of achieving singularity-free foot trajectories of healthy subjects in various exercises. This was then followed by building and testing another larger parallel robot to investigate the real-sized foot trajectories of patients. The overall results verify the designed robot’s capability in successfully tracking foot trajectories during different exercises. The thesis finally proposes a system of bilateral rehabilitation based on the concept of self-learning, where a passive parallel mechanism follows and records motion signatures of the patient’s healthy leg, and an active parallel mechanism provides motion for the impaired leg based on the kinematic mapping of the motion produced by the passive mechanism

MUSME 2011 4 th International Symposium on Multibody Systems and Mechatronics

El libro de actas recoge las aportaciones de los autores a través de los correspondientes artículos a la Dinámica de Sistemas Multicuerpo y la Mecatrónica (Musme). Estas disciplinas se han convertido en una importante herramienta para diseñar máquinas, analizar prototipos virtuales y realizar análisis CAD sobre complejos sistemas mecánicos articulados multicuerpo. La dinámica de sistemas multicuerpo comprende un gran número de aspectos que incluyen la mecánica, dinámica estructural, matemáticas aplicadas, métodos de control, ciencia de los ordenadores y mecatrónica. Los artículos recogidos en el libro de actas están relacionados con alguno de los siguientes tópicos del congreso: Análisis y síntesis de mecanismos ; Diseño de algoritmos para sistemas mecatrónicos ; Procedimientos de simulación y resultados ; Prototipos y rendimiento ; Robots y micromáquinas ; Validaciones experimentales ; Teoría de simulación mecatrónica ; Sistemas mecatrónicos ; Control de sistemas mecatrónicosUniversitat Politècnica de València (2011). MUSME 2011 4 th International Symposium on Multibody Systems and Mechatronics. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/13224Archivo delegad

Bio-Inspired Robotics

Modern robotic technologies have enabled robots to operate in a variety of unstructured and dynamically-changing environments, in addition to traditional structured environments. Robots have, thus, become an important element in our everyday lives. One key approach to develop such intelligent and autonomous robots is to draw inspiration from biological systems. Biological structure, mechanisms, and underlying principles have the potential to provide new ideas to support the improvement of conventional robotic designs and control. Such biological principles usually originate from animal or even plant models, for robots, which can sense, think, walk, swim, crawl, jump or even fly. Thus, it is believed that these bio-inspired methods are becoming increasingly important in the face of complex applications. Bio-inspired robotics is leading to the study of innovative structures and computing with sensory–motor coordination and learning to achieve intelligence, flexibility, stability, and adaptation for emergent robotic applications, such as manipulation, learning, and control. This Special Issue invites original papers of innovative ideas and concepts, new discoveries and improvements, and novel applications and business models relevant to the selected topics of ``Bio-Inspired Robotics''. Bio-Inspired Robotics is a broad topic and an ongoing expanding field. This Special Issue collates 30 papers that address some of the important challenges and opportunities in this broad and expanding field