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The paper describes the effects of the presence of a viscous fluid in the internal voids of a soft pulp for robotic finger designed according to the DLD (Differentiated Layer Design) concept.

A design methodology is presented, which makes it possible to optimize conically-shaped dielectric-elastomer (DE) linear actuators for known active material and required stiffness to an external load. The actuators are obtained by coupling DE films with compliant mechanisms that suitably modify the force generated by the elastomer films. The electromechanical properties of the DE films are determined through finite element analysis. The sizing of the compliant mechanisms is obtained through pseudo-rigid-body models and subsequently verified through finite element analysis. Experimental validation show that the designed actuators work as desired.

Actuators based on Dielectric Elastomers are a promising technology in robotic and mechatronic applications. The overall actuator performances are influenced by the non-linear and highly coupled electrical and mechanical responses of the employed materials. To date, the practical dynamic response and controllability of actuators based on Dielectric Elastomers are limited by the inadequacy of the employed activation strategy, which is based on voltage-regulated converters. In this paper a novel activation strategy is proposed for Dielectric Elastomer actuators which is based on a driving circuit derived from the flyback converter topology. A closed-loop position controller for Dielectric Elastomer actuators, which employs this driving circuit is also presented. Experimental results are reported which show that the proposed driving circuit outperforms the traditional strategies in terms of fast open-loop actuator activation and good closed-loop actuator controllability.

A novel mathematical procedure is proposed, which makes it possible to optimize lozenge-shaped dielectric-elastomer-based linear actuators for known materials and desired force/stroke requirements. Simulation results are provided which both demonstrate the efficacy of the novel procedure with respect to traditional design approaches and show that simpler, cheaper, lighter and better-behaved lozenge-shaped actuators can be conceived which do not require any integration of compliant frame elements.

A project-based learning experience has been recently developed at the University of Bologna within the second-level degree in Automation Engineering. The most relevant aspect is a co-tutoring activity jointly performed by teachers both from the mechanical area and from the automatic control area. The project was related to the design of an automated assembly system, developed for a local company that is leader in the production of technical cases. After a description of the educational goals, the paper discusses the phases of the activity and the main methodological aspects, then briefly presents the adopted tools for the design and simulation of the developed mechatronic system and finally discusses the achieved results.

Nel presente lavoro viene affrontato con un approccio sistematico il progetto concettuale di un manipolatore seriale per applicazioni mediche, consistenti nella diagnosi e nel trattamento della Labirintolitiasi: si tratta di una comune forma di vertigine, attualmente curata attraverso apposite manovre liberatorie eseguite manualmente dal medico specialista che muove il capo del paziente lungo traiettorie determinate. La metodologia proposta si può applicare in generale per la sintesi topologica e dimensionale di catene cinematiche seriali. Il processo di design viene automatizzato mediante una tecnica di ottimizzazione basata su algoritmi genetici che permette di valutare in maniera oggettiva le performance di ogni possibile configurazione cinematica del manipolatore rispetto a funzioni obiettivo opportunamente definite nelle varie fasi progettuali. Una descrizione della architettura prescelta nel caso del robot per il trattamento della Labirintolitiasi esemplifica i risultati ottenuti.