10 documents found, page 1 of 1
Deep convolutional neural networks applied to hand keypoints estimation
Santos, Bruno M.; Pais, Pedro; Ribeiro, Francisco M.; Lima, José; Goncalves, Gil; Pinto, Vítor H.Accurate estimation of hand shape and position is an important task in various applications, such as human-computer interaction, human-robot interaction, and virtual and augmented reality. In this paper, it is proposed a method to estimate the hand keypoints from single and colored images utilizing the pre-trained deep convolutional neural networks VGG-16 and VGG-19. The method is evaluated on the FreiHAND data...
Modeling and realistic simulation of a dexterous robotic hand: SVH hand use-case
Ribeiro, Francisco M.; Correia, Tiago; Lima, José; Goncalves, Gil; Pinto, Vítor H.Recent developments in dexterous robotic manipulation technologies allowed for the design of very compact, yet capable, multi-fingered robotic hands. These can be designed to emulate the human touch and feel, reducing the aforementioned need for human expertise in highly detailed tasks. The presented work focused on the application of two simulation platforms Gazebo and MuJoCo - to a use-case of a Schunk Five F...
Glove prototype for feature extraction applied to learning by demonstration pur...
Cerqueira, Tiago; Ribeiro, Francisco; Pinto, Vítor H.; Lima, José; Goncalves, GilThis article focuses on a sensorial glove prototype capable of acquiring hand motion and estimating its pose. The presented solution features twelve inertial measurement units (IMUs) to track hand orientation. The sensors are attached to a glove to decrease the project cost. The system also focuses on sensor fusion algorithms for the IMUs and further implementations, presenting the algebraic quaternion algorith...
Mecanum wheel robotic platform for educational purposes: a cost-effective approach
Viana, Emanuel; Pinto, Vítor H.; Lima, Jose; Goncalves, GilThis paper presents a cost-effective approach of a mecanum wheel robotic platform for educational propose on the development of an autonomous or remote controlled mobile robot with a four-wheel mecanum drive train. The main structure of the mobile robot was developed in Solidworks and it was built using additive manufacturing to validate in a real scenario. The main objective of developing this type of mobile p...
Nanographene Oxide Functionalization with Organic and Hybrid Organic-Inorganic ...
Jaggernauth, Aneeta; Silva, Ricardo M.; Neto, Miguel A.; Hortiguela, Maria J.; Goncalves, Gil; Singh, Manoj K.; Oliveira, Filipe J.; Silva, Rui F.The functionalization of nanographene oxide (GO) with polymers is desirable for increasing the interface compatibility of GO, thereby enabling its use in a variety of applications such as biomedical and energy storage systems. Typically, wet chemistry processes are used to achieve polymer functionalization of GO, having limitations of high heterogeneity, time consumption, and difficult purification processes. T...
Thin film versus paper-like reduced graphene oxide: Comparative study of struct...
Okhay, Olena; Goncalves, Gil; Tkach, Alexander; Dias, Catarina; Ventura, Joao; Ribeiro da Silva, Manuel Fernando; Valente Goncalves, Luis MiguelWe report fabrication of reduced graphene oxide (rGO) films using chemical reduction by hydrazine hydrate and rGO paper-like samples using low temperature treatment reduction. Structural analysis confirms the formation of the rGO structure for both samples. Current-voltage (I-V) measurements of the rGO film reveal semiconductor behavior with the maximum current value of similar to 3 x 10(-4) A. The current for ...
Synthesis and characterization of reduced graphene oxide/spiky nickel nanocompo...
Salimian, Maryam; Ivanov, Maxim; Deepak, Francis Leonard; Petrovykh, Dmitri Y.; Bdikin, Igor; Ferro, Marta; Kholkin, Andrei; Titus, Elby; Goncalves, GilThe surface modification of graphene oxide (GO) sheets with Ni nanoparticles has been a subject of intense research in order to develop new preeminent materials with increased performance for different application areas. In this work, we develop a new hydrothermal one-step method for the simple and controllable synthesis of reduced GO/nickel (GO/Ni) nanocomposites. Different reaction parameters have been invest...
Breakdown into nanoscale of graphene oxide: Confined hot spot atomic reduction ...
Goncalves, Gil; Vila, Mercedes; Bdikin, Igor; de Andres, Alicia; Emami, Nazanin; Ferreira, Rute A. S.; Carlos, Luis D.; Gracio, JoseNano-graphene oxide (nano-GO) is a new class of carbon based materials being proposed for biomedical applications due to its small size, intrinsic optical properties, large specific surface area, and easy to functionalize. To fully exploit nano-GO properties, a reproducible method for its production is of utmost importance. Herein we report, the study of the sequential fracture of GO sheets onto nano-GO with co...
Surface modification of cellulosic fibres for multi-purpose TiO(2) based nanoco...
Goncalves, Gil; Marques, Paula A. A. P.; Pinto, Ricardo J. B.; Trindade, Tito; Pascoal Neto, CarlosVegetable cellulose fibres have been surface modified using the hydrolysis of tetraethoxysilane (TEOS), octyltrimethoxysilane (OTMS) or phenyltrimethoxysilane (PTMS), followed by the layer-by-layer deposition of previously synthesized TiO2 nanoparticles. Raman, FTIR and 29Si Solid State NMR spectroscopies, and SEM were used to characterize the resulting nanocomposites. Water contact angle measurements were perf...
Superhydrophobic cellulose nanocomposites
Goncalves, Gil; Marques, Paula A. A. P.; Trindade, Tito; Neto, Carlos Pascoal; Gandini, AlessandroSuperhydrophobic cellulose nanocomposites were prepared using a multi-step nanoengineering process. The combination of different techniques made it possible to construct novel features at the ensuing surface, characterized by both an increase in its roughness induced by amorphous silica particles and a reduction in its energy insured by perfluoro moieties, giving rise to water contact angles approaching 150◦. T...