Modellbasierte Kraftregelung einer mit pneumatischen Muskeln angetriebenen Parallelplatform

In the present work, a force and torque controlled Gough-Stewart type parallel platform driven by six actuator legs was developed and evaluated. Each actuator consists of a fluidic muscle which is combined with a prestressed coil spring in order to produce compressive as well as tensile forces. The platform shall be controlled such that arbitrary force functions can be simulated. Through geometric limit analyses, it was verified that the workspace of the mobile platform suffices to the required motion range. The model-based force control of each actuator uses an exponential approximation of the transient pressure responses. The six actuator control loops are embedded into the force and torque control of the parallel manipulator. The platform-control algorithm includes a kinetostatic platform model, which com-putes the corresponding required leg forces in order to achieve the target forces and torques at the end effector of the platform. It was shown that the target end-effector forces and torques, which do not pursue rapid changes, can be produced effectively with the developed parallel manipulator and the established platform control. The steady-state performance of the developed control algorithm sufficed to the requirements of a fine-tuned force and torque control. The manipulator was designed for its future application as a physical simulator of cervical spine motion for assessing effects of, e.g., implants, surgical treatments, etc.Die vorliegende Arbeit befasst sich mit der Entwicklung und Evaluierung einer kraftgeregelten Gough-Stewart Parallelplattform, die von sechs Aktoren angetrieben wird. Die Aktoren bestehen jeweils aus einem pneumatischen Muskel und einer vorgespannten Druckfeder. Die Plattform wird so geregelt, dass beliebige Kraft- und Momentenverläufe erstellt werden können. Durch die geometrische Analyse der Endlagen wurde verifiziert, dass der geforderte Arbeitsraum durch die Plattform erreicht werden kann. Jeder einzelne Aktor wird durch eine modellbasierte Kraftregelung kontrolliert, die unter anderem die Druckbeaufschlagung eines pneumatischen Muskels durch exponentielle Funktionen annähert. Die sechs Regelschleifen der Aktoren sind der Kraft- und Momentenregelung der Parallelplattform untergeordnet. Die Plattformregelung benutzt das kinetostatische Modell der Plattform und berechnet die jeweiligen Aktorkräfte, die zum Erreichen der aktuellen Sollkraft und Sollmomentes an der Plattform notwendig sind. Es wurde gezeigt, dass die geforderten Zielkräfte und Momente effektiv mit der kraftgeregelten Plattform produziert werden können und im stationären Bereich der Sprungantworten eine genaue Kraftregelung möglich ist. Die Parallelplattform wurde konzipiert für ihre zukünftige Anwendung als physikalischer Simulator der menschlichen Halswirbelsäule, unter anderem für die präoperative Analyse chirurgischer Eingriffe, Implantate etc

Design and Evaluation of AIRGAIT Exoskeleton\u27s Leg Orthosis: Development of a Control Scheme and Strategy for a Noble Control of Antagonistic Mono- and Bi-Articular Actuators

芝浦工業大学201

Development of a 3-DOF motion simulation platform

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: The successful development of a three degree of freedom motion simulation platform, capable of simulating a vessel’s flight deck at sea, is presented. The motion simulation platform was developed to practically simulate and test an unmanned aerial vehicle’s capability of landing on a moving vessel, before practically being demonstrated on an actual vessel. All aspects of the motion simulation platform’s development are considered, from the conceptual design to its practical implementation. The mechanical design and construction of a pneumatic motion simulation platform, as well as the electronics and software to enable the operation of this motion simulation platform, are presented. Mathematical models of the pneumatic process and platform orientation are developed. A controller architecture capable of regulating the pneumatic process, resulted in the successful control of the motion simulation platform. Practical motion simulation results of one of the South African Navy Patrol Corvettes, demonstrate the motion simulation platform’s success. The successful development of the motion simulation platform can largely be attributed to extensive research, planning and evaluation of the different development phases.AFRIKAANSE OPSOMMING: In hierdie studie word die suksesvolle ontwikkeling van ’n drie-grade-van-vryheid bewegingsimulasieplatform, wat in staat is daartoe om ’n skip se vliegdek ter see te simuleer, aangebied. Die bewegingsimulasieplatform is ontwikkel om ’n onbemande lugvaartuig se vermoë om op ’n bewegende skip te land, te simuleer en te toets, voor dit op ’n werklike skip gedemonstreer word. Alle aspekte van die ontwikkeling van die bewegingsimulasieplatform word in ag geneem – van die konsepontwerp tot die praktiese implementering daarvan. Die meganiese ontwerp en konstruksie van ’n pneumatiese bewegingsimulasieplatform word bespreek, sowel as die elektronika en programmatuur wat die werking van hierdie bewegingsimulasieplatform bemoontlik. Wiskundige modelle van die pneumatiese proses en platformoriëntering word ontwikkel. ’n Beheerderargitektuur wat in staat is daartoe om die pneumatiese proses te reguleer, lei tot die suksesvolle beheer van die bewegingsimulasieplatform. Praktiese resultate van die bewegingsimulering van een van die Suid-Afrikaanse Vloot se patrolliekorvette wys daarop dat die bewegingsimulasieplatform wel suksesvol is. Die geslaagde ontwikkeling van die bewegingsimulasieplatform kan grootliks toegeskryf word aan omvangryke navorsing, beplanning en evaluering van die onderskeie ontwikkelingsfases

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