This paper presents the design and testing of an artificial finger based partly on biomechanics. The prototype was manufactured in acrylonitrile butadiene styrene plastic using a rapid prototyping three-dimensional printer. The flexing of the finger was realized by Ni-Ti shape-memory alloy (SMA) wires with diameters of 0.3 mm, activated by resistive heating. The results obtained show the new prototype to be superior in performance, mainly in terms of angles of rotation of the phalanges, compared with some SMA fingers discussed in the literature.

This paper presents the development of a robotic finger driven by nonconventional actuators, consisting of thin shape memory alloy (SMA) wires. In order to monitor and control the angles formed by each phalanx, a specific system for capturing and interpreting digital images was implemented. By image processing, this system is capable to determine the angles without the need for installation of phalanx rotation sensors, leading to weight and volume reduction of the prototype. For this artificial vision system, a simple camera with a fuzzy logic control technique was used, which was very effective in monitoring the position of the robotic finger.

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Currently possible solutions for alternative electric power generation have been the subject of interest of many researchers. More recently, the possibility of generating low power electricity has been studied, being enough to meet the demand of some electronic systems. Systems such as wireless sensors or remote communication which has low power consumption can be benefited. Among various technologies for producing alternative electricity, the use of vibratory energy and deformation of structures can be used to generate electricity. In this conversion, piezoelectric materials that convert mechanical strain energy into electrical energy are employed. Thus, this work presents a characterization study of a piezoelectric material (PZT), Lead Zirconate Titanate, with the purpose of generating electricity. For the characterization experiment a cylindrical PZT was employed, subjected to compression in a cyclic manner in the axial direction. An experimental apparatus was designed and instrumented to capture the force, acceleration, voltage and electric power generated due this piezoelectric cell. Initially simulations were developed in order to guide the experimental set of actions. From the experimental results with a piezoelectric cell, a piezoelectric generator was designed with three cells and characterized. Results of the physical parameters related to the characterization are presented.

In this work, a robotic hand has been developed. This hand is driven by SMA (Shape Memory Alloy) wires. Some researches has showed the high rejection rate by the amputees using prosthetic upper limbs due to several problems, such as weight, high noise and need of anthropomorphism. In this context, it is presented the development of a robotic hand which is not driven by conventional actuators, in this case, SMA actuators. The mechanical structure of the robotic hand was designed using a computer program (CAD) and subsequently manufactured in ABS (acrylonitrile butadiene styrene) polymer by a rapid prototyping machine (3D printer). The robotic hand was instrumented with a bend sensor (also known as Flexsensor) to monitor the angles formed by each phalanx. The data presented, as the obtained angles, were quite satisfactory for this application. In order to corroborate the data presented by the bend sensor, a system was developed using a camera to procedure a non-contact measurement with image processing.