Additive Manufactured Piezoelectric-Driven Miniature Gripper.

In several cases, it is desirable to have prototypes of low-cost fabrication and adequate performance. In academic laboratories and industries, miniature and microgrippers can be very useful for observations and the analysis of small objects. Piezoelectrically actuated microgrippers, commonly fabricated with aluminum, and with micrometer stroke or displacement, have been considered as Microelectromechanical Systems (MEMS). Recently, additive manufacture using several polymers has also been used for the fabrication of miniature grippers. This work focuses on the design of a piezoelectric-driven miniature gripper, additive manufactured with polylactic acid (PLA), which was modeled using a pseudo rigid body model (PRBM). It was also numerically and experimentally characterized with an acceptable level of approximation. The piezoelectric stack is composed of widely available buzzers. The aperture between the jaws allows it to hold objects with diameters lower than 500 µm, and weights lower than 1.4 g, such as the strands of some plants, salt grains, metal wires, etc. The novelty of this work is given by the miniature gripper's simple design, as well as the low-cost of the materials and the fabrication process used. In addition, the initial aperture of the jaws can be adjusted, by adhering the metal tips in the required position.

Novel Electrothermal Microgrippers Based on a Rotary Actuator System.

Microgrippers are devices that have found applications in various fields of research and industry. They are driven by various actuation methods. In this article, an electrothermal rotary actuator recently proposed in the literature is explored to obtain a novel microgripper design (Model 1). In addition, the use of the rotary actuator as part of the chevron actuated microgrippers (Model 2) is also discussed. The theoretical analysis of the rotary actuator is supported by an equivalent U-shaped-like microactuator. The small error values validate the approximation used. Numerical modeling is performed with ANSYSTM (Student version 2022, ANSYS, PA, USA). A comparison of theoretical and numerical results provides acceptable error values. The total inter-jaw displacement values obtained for models 1 and 2 are 12.28 µm and 21.2 µm, respectively, and the reaction force is 8.96 µN and 34.2 µN, respectively. The performance parameters of both microgrippers could make their use feasible for different nanoapplications. Model 2 can be used when higher force and displacement are required.

Evaluación tecnológica y comercial de patentes universitarias a partir de la identificación de oportunidades comerciales en transferencia de tecnología / Technological and commercial evaluation of university patents based on the identification of commercial opportunities in technology transfer

Resumen Ante la transición a universidades emprendedoras, existe la tendencia a incrementar el patentamiento, aunque sin un estudio profundo del potencial comercial, por lo que el porcentaje de los productos que lo logran es muy bajo. El objetivo de esta investigación fue diseñar una estrategia de evaluación tecnológica y comercial de patentes universitarias a partir de la identificación de oportunidades en transferencia de tecnología (TT). Para ello, se examinaron 269 solicitudes de patente de la Benemérita Universidad Autónoma de Puebla (BUAP) y de la Universidad Autónoma del Estado de Morelos (UAEM), de acuerdo con la Clasificación Internacional de Patentes (CIP), en un periodo de 10 años (2009-2018), mediante 4 pasos: (a) construcción de la base de datos con la herramienta del Instituto Mexicano de Propiedad Intelectual, (b) identificación de las capacidades inventivas, a través de la Organización Mundial de la Propiedad Intelectual, (c) distribución por industrias de intensidad y oportunidad de mercado tecnológico, de acuerdo con la Organización para la Cooperación y el Desarrollo Económicos, y (d) análisis del comportamiento del mercado, mediante el estudio de las 36 solicitudes del área farmacéutica de ambas universidades. Los resultados mostraron que el 68.4 % de la BUAP y 75.6 % de la UAEM presentan un posicionamiento competitivo predominante en industrias de alta y mediana-alta tecnología. La ventaja de la herramienta propuesta es que permite reconocer la oportunidad del mercado tecnológico a partir de la construcción de escenarios relacionados con el comportamiento de la CIP.

Abstract Given the transition to entrepreneurial universities, there is a tendency to increase patenting, although without a deep study of the commercial potential. Therefore, the percentage of those developments that succeed is very low. The objective of this research was to develop a strategy for the technological and commercial evaluation of university patents, based on the identification of commercial opportunities in technology transfer (TT). Patent applications from the Benemerita Universidad Autonoma de Puebla (BUAP) and the Universidad Autonoma del Estado de Morelos (UAEM) were used for the study. The methodology consisted of the analysis of 269 patent applications in a period of 10 years 2009-2018, in accordance with the statistical International Patent Classification (IPC), through 4 steps: (a) construction of the patent database, with the use of the patent tool of the Mexican Institute of Intellectual Property, (b) identification of inventive capabilities, through the World Intellectual Property Organization, (c) distribution by industries of intensity and technological market opportunity, with the tool of the Organization for Economic Cooperation and Development, and (d) analysis of market behavior, through the study of the 36 applications of the pharmaceutical patent area, from both universities. The results showed that 68.4 % of BUAP and 75.6 % of UAEM reflected a predominantly competitive positioning in high technology and medium-high technology industries. The advantage of the proposed tool is that it allows the recognition of the technological market opportunity based on the construction of scenarios related to the IPC behavior.

Z-Shaped Electrothermal Microgripper Based on Novel Asymmetric Actuator.

Based on a V-shaped microactuator with a pair of beams, modifications were made to the length and width of a microactuator to observe the effects. A theoretical approach and numerical characterization of the modified microactuator were performed. Its performance was compared to a similar microactuator with equal beam widths, and a V-shaped microactuator. The proposed microactuator, fed at 2 V, compared to the V-shaped actuator, showed a 370.48% increase in force, but a 29.8% decrease in displacement. The equivalent von Mises stress level increased (until 74.2 MPa), but was below the silicon ultimate stress. When the modified microactuator was applied to the proposed microgripper, compared to the case using a V-shaped actuator, the displacement between the jaws increased from 0.85 µm to 4.85 µm, the force from 42.11 mN to 73.61 mN, and the natural frequency from 11.36 kHz to 37.99 kHz; although the temperature increased, on average, from 42 °C up to 73 °C, it is not a critical value for many microobjects. The maximum equivalent von Mises stress was equal to 68.65 MPa. Therefore, it has been demonstrated that the new modified microactuator with damping elements is useful for the proposed microgripper of novel geometry, while a reduced area is maintained.

Optical Sensor, Based on an Accelerometer, for Low-Frequency Mechanical Vibrations.

This article documents the design, manufacture, and testing of a silicon inertial optical sensor for low-frequency (lower than 2 kHz) applications. Three accelerometer designs optimized by parameterization using Finite Element Analysis were considered. The accelerometers were manufactured and the one with the highest performance at low frequency was chosen for testing, which was attached to a steel package. The feasibility of using probes, based on micro-machined sensing elements, to measure mechanical vibrations with high resolution was also studied. The detection is performed with an air interferometer, eliminating the need for electric signals that are susceptible to electromagnetic interference and large temperature variations. From the fabrication technology using only a silicon wafer with both sides etched, the frequency response of the sensor, temperature operation (higher than 85 °C) and with a resolution of 17.5 nm, it was concluded that is achievable and feasible to design and manufacture an optical vibration sensor for potential harsh environments with a low cost.