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This paper presents the use of surface electromyographic (sEMG) signals for the actuation of soft pneumatic artificial muscles. The idea behind this paper is finding a relationship between a natural muscle and an artificial muscle, do it through an analysis of the sEMG data. We start from the characterization of a specific soft pneumatic artificial muscle and we relate the root mean square value of the sEMG signal to the contraction of the actuator itself. This work might pave the way for the development of intuitive wearable interfaces for the actuation of soft robots.

Over the past years, a wide range of dental implants has been proposed. In general, the dentists may find the best solutions according to the specific needs of the patients. A variety of factors influences the level of osseointegration and, consequently, the anchorage of the implant to the bone. The stress transfer mechanism along the bone-implant interface depends upon the surface area of the bone-implant contact. Great efforts have been devoted to the design of 3D porous lattice structures with tailored architectural features in order to reduce the implant stiffness as well as to favour bone ingrowth, thus stabilizing the device. Accordingly, the aim of the current study was to provide further insight into the design criteria for dental implants. In particular, starting from a screw implant (Implant A), different concepts of dental implants were developed: i) Implants B1–B5, with lattice shell surrounding a solid core, without thread; ii) Implant C, with lattice structure; iii) Implant D as topography optimized implant. Finite element analysis on the several models of bone-implant provided interesting information in terms of stress distributions in cortical and trabecular bone. Some differences among the implants may be ascribed to the different design criteria.

Factory acceptance test is the inspection of equipment and components at the supplier’s premises before delivery or final inspection. However, this control can represent a considerable cost for the customer, especially when the manufacturer’s company is geographically far from the customer one and inspections must be frequent. In this paper, the authors present a framework to support the factory acceptance test based on augmented reality (AR) techniques and model-based definition aimed at dimensional checks that does not require the physical presence of the customer at the supplier's premises. The supplier must be previously equipped with an automatic measuring machine. Once the component under inspection is placed inside the machine, this reads the type and the position of the features to be measured along with the related specification limits directly from the annotated 3D model of the component. The results are automatically transmitted to the customer’s site. Through a tablet, the supplier, guided by the customer, reads the results of the measures directly on the measured object through augmented or mixed reality techniques. Any out-of-specification dimension can be remeasured in real time with the customer’s remote assistance using traditional measurement techniques. The proposed architecture, at an advanced stage of experimentation, is discussed with reference to an industrial case study proposed and using an entry level commercial 3D scanner.

Titanium and its alloys are widely employed in commercial dental devices. Because the surface morphology and chemical composition of Ti-based dental implants play a relevant role in osseointegration, three different commercial threaded implants have been investigated by scanning electron microscopy and X-ray photoelectron spectroscopy (XPS). The Implants A and C were made of pure Ti whereas the Implant B was made of Ti6Al4V alloy. Obtained results evidenced the common features and differences due to specific process parameters used in the treatments of mordanting and sandblasting for surface roughening. Implant A exhibits a uniform surface covered by very small dimples of about 1–2 μm. The surface of Implant B is not homogeneous: The thread tops present an irregular morphology (dimples size >10 μm) while finer dimples (about 1 μm) are observed along the thread flanks and valleys. Implant C shows an irregular morphology with dimples of different sizes and shapes distributed on thread tops, flanks, and valleys. XPS analyses revealed the presence of metal oxides: TiO2 in all the implants; Al2O3 and V2O5 only in the implant B. Moreover, these results demonstrated that Mg2SiO4 is present on the surface of Implant A, probably due to a specific preparation process. Obtained results have been discussed on the basis of the factors promoting the osseointegration.

Objective and reliable assessment of motor functions, such as dexterity, is a key point for evaluating worker’s abilities. In this context, the proposed work presents a tool for objective automatic assessment of the Minnesota Dexterity Test using cameras with depth sensors. Typical performance measurements (i.e., total time and associated percentiles) were estimated using custom algorithms. In addition, the possibility to identify the qualifiers for the code d440 of the International Classification of Functioning, Disability and Health was implemented in the developed algorithms. The proposed tool can also identify the mistakes most frequently committed by the subjects. To prove the capabilities of the proposed method, a series of experimental trials was conducted with 10 healthy young volunteers. Results showed that the developed tool helps clinicians to obtain performance feedback and evaluate patients’ dexterity quickly without bias.

Made available in DSpace on 2021-06-25T11:13:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 The aim of the present study was to investigate the effect of shrinking and no shrinking dental filling materials combination in posterior restorations under the combined effects of polymerization shrinkage and occlusal load by means of 3D Finite Elements Analysis. Six computer-generated and restored class I or class II cavities models of a lower molar were designed in the CAD software and evaluated according to the cavity and restorative procedure. Different shrinking and no shrinking adhesive materials combination with diverse Young’s modulus were considered. A food bolus was modeled on the occlusal surface replicating the chewing load using static linear analyses Polymerization shrinkage was simulated for the shrinking different restorative materials. The maximum principal stress was selected as analysis criteria. All models exhibited higher stresses along the dentine restoration interfaces with different magnitude and a similar stress trend along enamel restoration interface. Stress values up to 22 MPa and 19 MPa were recorded in the enamel and restoration, respectively. The use of elastic not shrinking material layer in combination with bulk fill composite reduced the stress magnitude in dentine and enamel to replace dental tissues. Class I and class II posterior cavities adhesively restored with shrinking filling material’s combination showed the most unfavorable stress concentrations and the multilayer technique is a promising restorative alternative in posterior adhesive restorations when deep dentin and enamel volumes are missing. School of Dentistry University of Naples Federico II, via S. Pansini 5 Department of Dental Materials and Prosthodontics Institute of Science and Technology São Paulo State University-UNESP Fraunhofer JL IDEAS Department of Industrial Engineering University of Naples Federico II Endodontic Clinical Section School of Dentistry Department of Biomedical and Neuromotor Sciences University of Bologna-Alma Mater Studiorum School of Dentistry University of Taubaté–UNITAU, Taubaté Department of Dental Materials and Prosthodontics Institute of Science and Technology São Paulo State University-UNESP

This research activity aims to develop new cycling gloves. A first step was focused on the definition of the functional requirements through user centred design methods. Since vibrations coming to the hand-arm system of a cyclist have a considerable effect a second step was concentrated on the analysis of hand-arm vibrations in road cycling. The paper shows results of laboratory tests executed for three different hand sizes, three different frequency ranges, with two different type of gloves and without gloves. Load conditions used for the test were determined with a former field test. Results obtained were analysed using Analysis of Variance (ANOVA), that showed no significant effect of existing gloves in reducing vibration transmissibility. This led to the need of new kind of cycling gloves that could reduce those vibrations and increase the cyclist’s comfort.

Applications as robotic harvesting or pick and place in the agrifood domain require robotic grippers able to gently manipulate delicate products, while guaranteeing high gripping power and adhesion forces on smooth surfaces. Existing soft grippers are mainly based on pneumatic bending actuators which can guarantee a gentle manipulation, but they suffer from low gripping power and possibility of slip of the manipulated object. This paper describes a novel design concept of soft robotic pneumatic gripper with embedded suckers. The concept consists of four soft fingers, each one comprising an elastomeric structure with two separate air paths, one for pressurizing the finger for generating bending motion, one for vacuum–based adhesion to the object’s surface via suction pads distributed along the surface of the finger. In this work we highlight the concept design of the mechanical system and the pneumatic control unit.

Titanium alloys (e.g., Ti6Al4V) have been widely considered for the design of biomedical implants. To avoid stress shielding effects, bone atrophy and implant loosening bone, 3D porous devices with controlled geometry and architecture should represent a promising solution. Several cellular structures were already investigated to obtain a wide range of mechanical properties. Many studies focused on the mechanical performance of diamond and body-centered-cubic. Different kinds of porous and semi-porous femoral stems were also proposed and analyzed. Accordingly, the aim of the current research was to provide further insight into the design of solid-lattice hybrid structures through a two-step process involving the classical and lattice topology optimization. A cementless femoral stem was considered as a case study. The solid isotropic material with penalization (SIMP) was used at varying values of the penalty factor and the effect of the geometrical features of each beam forming the lattice structure was also determined. Differences were found in terms of functional and structural performances according to the selected strategy for the design of the solid-lattice hybrid structures, as a consequence of the material distribution/layout and geometrical features.

Nowadays, the commercial translation of additive manufacturing technologies for scaffolds fabrication is still a challenge. The production methodology of 3D scaffolds for tissue regeneration is a complex and discontinuous process involving several stages, from the isolation of the stem cells to the dynamic cell culture in vitro. Even though in this scenario industries are increasingly implementing automated robotic systems, current technologies are not enough to realize a large industrial scale scaffold fabrication. Accordingly, a relevant improvement could raise from the implementation of a modern collaborative workplace in an existing production line, combining strength endurance and accuracy of cobots, with intelligence, flexibility, and adaptability of the human being. Such a solution overcomes limits related to the low level of process control, low productivity, and risk of contaminations. Therefore, the current work proposes a systematic approach to the design of a collaborative workplace for biomanufacturing of 3D scaffolds. Starting from an overview of basic concepts on scaffolds for tissue engineering and additive manufacturing, as well as from an analysis of automation solutions in cell culture applications, a design methodology section is reported. The paper provides a further insight into the potentials to upscale the scaffolds manufacturing process, taking advantage of the huge possibilities given from the Human-Robot Collaboration and gives evidence of critical features for workplace definition.

Additive manufacturing (AM) allows the development of novel and customized products with tailored properties. However, the application of extrusion-based AM techniques (i.e., fused deposition modeling - FDM) in the design of functional parts is often limited because of the poor mechanical performance as a consequence of the nature of the process to build the object in a layer-by-layer fashion. In the current study, the impact resistance of the 3D printed polyethylene terephthalate glycol-modified (PETG) and high impact polystyrene (HIPS) was evaluated as a function of three printing parameters (i.e., printing temperature, layer height and line width). Izod-type test specimens were fabricated and analyzed according to the ASTM D256. The contribution of each factor was properly analyzed. The results also indicated that the printing temperature was the most significant parameter for the impact resistance of 3D printed PETG and HIPS. The obtained findings may be considered as valid only within the limit of parameters and ranges investigated in the current study.

In this paper, we present a biomechanical analysis of the upper body, which includes upper-limb, neck and trunk, during the execution of overhead industrial tasks. The analysis is based on multiple performance metrics obtained from a biomechanical analysis of the worker during the execution of a specific task, i.e. an overhead drilling task, performed at different working heights. The analysis enables a full description of human movement and internal load state during the execution of the task, thought the evaluation of joint angles, joint torques and muscle activations. A digital human model is used to simulate and replicate the worker’s task in a virtual environment. The experiments were conduced in laboratory setting, where four subjects, with different anthropometric characteristics, have performed 48 drilling tasks in two different working heights defined as low configuration and middle configuration. The results of analysis have impact on providing the best configuration of the worker within the industrial workplace and/or providing guidelines for developing assistance devices which can reduce the physical overloading acting on the worker’s body.