MPU6050 MODULE CONTROL UNIT ON THE IC BUS BASED ON A MICROCONTROLLER

Рассматривается модуль GY-521, на котором установлена микросхема MPU6050, объединяющая в одном корпусе акселерометр, гироскоп и температурный датчик. Такие датчики изготовлены на основе микромеханических систем (МЭМС), основным преимуществом которых является малый размер, низкое энергопотребление и небольшая стоимость. Одновременное использование акселерометра и гироскопа позволяет определить изменение движения тела в трехмерном пространстве. Рассмотрены основные характеристики используемого модуля. Управление микросхемы осуществляется с помощью архитектуры интерфейса IC «ведущий-ведомый». В работе ведомым является MPU6050, а ведущим (производит запрос на чтение или запись данных) является микроконтроллер, имеющий в своем составе аппаратную шину передачи данных IC. Показана возможная программная реализация алгоритма подключения нескольких ведомых устройств (шести микросхем MPU6050). Представлена принципиальная схема подключения к одному порту ввода-вывода микроконтроллера. Рассмотрен алгоритм работы микроконтроллера с подключенными микросхемами (шестью) MPU6050. Приведены пример программы (с использованием языка ассемблер) инициализации связи с MPU6050, а также программа считывания данных для снятия последних измерений акселерометра, гироскопа, температурного датчика. Применение нескольких модулей с одновременным считыванием с них информации позволяет осуществлять контроль систем управления полетом, имеющих совокупность нескольких управляющих поверхностей и устройств The paper considers the GY-521 module, which is equipped with the MPU6050 chip, which combines an accelerometer, a gyroscope and a temperature sensor in one housing. Such sensors are made on the basis of micromechanical systems (MEMS), the main advantages of which are small size, low power consumption and low cost. The simultaneous use of an accelerometer and a gyroscope allows you to determine the change in the movement of a body in three-dimensional space. We considered the main characteristics of the module used. The control of the chip is carried out using the architecture of the IC interface "master-slave". In operation, the MPU6050 is the host, and the master (makes a request to read or write data) is a microcontroller that has an IC hardware data bus. We show a possible software implementation of the algorithm for connecting multiple slave devices (six MPU6050 chips). We present a schematic diagram of the connection to a single I/O port of the microcontroller. We consider the algorithm of operation of the microcontroller with connected chips (six) MPU6050. We give an example of a program (using the assembly language) for initializing communication with the MPU6050, as well as a program for reading data for taking the latest measurements of the accelerometer, gyroscope, and temperature sensor. The use of several modules with simultaneous reading of information from them allows you to control flight control systems that have a set of several control surfaces and devices

Optocapillarity-driven assembly and reconfiguration of liquid crystal polymer actuators

Realizing programmable assembly and reconfiguration of small objects holds promise for technologically-significant applications in such fields as micromechanical systems, biomedical devices, and metamaterials. Although capillary forces have been successfully explored to assemble objects with specific shapes into ordered structures on the liquid surface, reconfiguring these assembled structures on demand remains a challenge. Here we report a strategy, bioinspired by Anurida maritima, to actively reconfigure assembled structures with well-defined selectivity, directionality, robustness, and restorability. This approach, taking advantage of optocapillarity induced by photodeformation of floating liquid crystal polymer actuators, not only achieves programmable and reconfigurable two-dimensional assembly, but also uniquely enables the formation of three-dimensional structures with tunable architectures and topologies across multiple fluid interfaces. This work demonstrates a versatile approach to tailor capillary interaction by optics, as well as a straightforward bottom-up fabrication platform for a wide range of applications.

A Review on Reconfigurable Liquid Dielectric Antennas

The advancements in wireless communication impose a growing range of demands on the antennas performance, requiring multiple functionalities to be present in a single device. To satisfy these different application needs within a limited space, reconfigurable antennas are often used which are able to switch between a number of states, providing multiple functions using a single antenna. Electronic switching components, such as PIN diodes, radio-frequency micromechanical systems (RF-MEMS), and varactors, are typically used to achieve antenna reconfiguration. However, some of these approaches have certain limitations, such as narrow bandwidth, complex biasing circuitry, and high activation voltages. In recent years, an alternative approach using liquid dielectric materials for antenna reconfiguration has drawn significant attention. The intrinsic conformability of liquid dielectric materials allows us to realize antennas with desired reconfigurations with different physical constraints while maintaining high radiation efficiency. The purpose of this review is to summarize different approaches proposed in the literature for the liquid dielectric reconfigurable antennas. It facilitates the understanding of the advantages and limitations of this technology, and it helps to draw general design principals for the development of reconfigurable antennas in this category.

Topological properties of aftershock clusters in a viscoelastic model of quasi-brittle failure

<p>Material failure at different scales and processes can be modeled as an emergent feature in terms of avalanche dynamics in micromechanical systems. <br>Event-event triggering -or aftershocks- is common in seismological catalogs and acoustic emission experiments <sup>[1]</sup> among other phenomena.<br>Stochastic branching and linear Hawkes processes are used to model the statistical properties of catalogs.  In the micromechanical approach, viscoelastic stress transfer and after-slip are among the proposed mechanism of aftershocks. Here we ask this simple question: '<em>Do aftershock sequences in micromechanical models agree with such epidemic branching paradigm?</em>'</p><p><br>We introduce two fibrous models as prototypes of viscoelastic fracture <sup>[2]</sup> which <em>(i)</em> provides an analytical explanation to the acceleration of activity in absence of critical failure observed in acoustic emission experiments <sup>[3]</sup>; <em>(ii)</em> reproduce the typical spatio-temporal properties of triggering found in field catalogs, acoustic emission experiments; but <em>(iii)</em> display discrepancies with the branching topological properties predicted by stochastic models <sup>[4]</sup>, probably due to physical constrains. <br><br>[1] J. Baró et al.,<em> Phys. Rev. Lett.</em> <strong>110</strong> (8), 088702 (2013).<br>[2] J. Baró, J. Davidsen, <em>Phys. Rev. E</em>  <strong>97</strong> (3), 033002 (2018).<br>[3] J. Baró, et al., <em>Phys. Rev. Lett.</em> <strong>120</strong> (24), 245501 (2018).<br>[4] S. Saichev, et al., <em>Pure and App. Geoph.</em> <strong>162</strong> (6), 1113-1134 (2005).</p>

Design and Analysis of Capacitive Micromachined Ultrasonic Transducer

Background:Objective:To simulate a Micromechanical systems (MEMS) based CMUT working as a transmitter with the existing design and provide comparison within the possible architectural geometries.Methods:FEM simulation software COMSOL is used to simulate the 3D model of the transducer radiating in the air. The classical thin-plate theory is employed to solve for CMUT with a circular shape which is sufficient when the ratio of the diameter to thickness of the plate is very large, an aspect common in CMUTs. The Galerkin-weighted residual technique is used to get a solution for thin plate equation with the presumption that the deflections are small in comparison to the thickness of the plate.Results:The resonant frequency of CMUT with different geometries have been calculated. The deflection of membrane with applied DC bias is shown along with collapse voltage calculation. The generated ultrasound is shown with the AC bias superimposed on the DC bias. The capacitance change with the increasing DC voltage is discussed. The deflection of membrane is maximum as the resonance frequency is proved.Conclusion:The review of Capacitive Micromachined Ultrasonic Transducer architectures with different shapes is highlighted. The working behavior of CMUT with suitable dimension is simulated in 3D providing researcher data to wisely choose the CMUT prior to the fabrication. The CMUT is prioritized on various characteristics like wafer area utilization, deflection percentage within the cavity and durability of the transducer.

Surface-Controlled Molecular Self-Alignment in Polymer Actuators for Flexible Microrobot Applications

Polymer actuators are important components in lab-on-a-chip and micromechanical systems because of the inherent properties that result from their large and fast mechanical responses induced by molecular-level deformations (e.g., isomerization). They typically exhibit bending movements via asymmetric contraction or expansion with respect to changes in environmental conditions. To enhance the mechanical properties of actuators, a strain gradient should be introduced by regulating the molecular alignment; however, the miniaturization of polymer actuators for microscale systems has raised concerns regarding the complexity of such molecular control. Herein, a novel method for the fabrication of micro-actuators using a simple molecular self-alignment method is presented. Amphiphilic molecules that consist of azobenzene mesogens were located between the hydrophilic and hydrophobic surfaces, which resulted in a splayed alignment. Thereafter, molecular isomerization on the surface induced a large strain gradient and bending movement of the actuator under ultraviolet-light irradiation. Moreover, the microelectromechanical systems allowed for the variation of the actuator size below the micron scale. The mechanical properties of the fabricated actuators such as the bending direction, maximum angle, and response time were evaluated with respect to their thicknesses and lengths. The derivatives of the polymer actuator microstructure may contribute to the development of novel applications in the micro-robotics field.