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This paper aims to present a unified motion control scheme for quadcopters which not only solves the point stabilization and trajectory tracking problems but also the path following problem.

The control problem is solved based on the kinematic model of the unmanned aerial vehicles (UAV). Next, a dynamic compensation controller is considered through of a quadcopter-inner-loop system to independently track four velocity commands: forward, lateral, up/downward and heading rate. Stability and robustness of the whole control system are proved through the Lyapunov’s method. To evaluate the controller’s performance, a multi-user application which allows bilateral communication between a ground station and the Phantom 3 PRO quadrotor is developed.

The performance of the proposed unified controller is shown through real experiments for the different motion control objectives: point stabilization, trajectory tracking and path following. The experiments confirm the capability of the unified controller to solve different motion problems by an adequate selection of the control references.

This work proposes the design of three types of motion controllers, which can be switched to comply a task in outdoor. Based on the software development kit provided by the company DJI, an application to get and send data to the UAV is developed. By means of this application, the three tasks are tested and the robustness of the controllers is proved.

This study analyzes the digital competencies and the attitude toward the use of information and communication technologies (ICT) in secondary school teachers of the Javier Heraud Public Educational Institution, Lima, Peru, according to the technology, pedagogy, and content knowledge (TPACK) model, which focuses on knowledge about technology knowledge (TK), pedagogical content (PK) and content knowledge (CK). This implies that it is important to take these components into account in the development of teaching work, in order to contribute to the quality of student learning, within the framework of the restrictions established due to the global health emergency. The study is based on the quantitative approach, type of correlational research and cross-sectional design, the sample consisted of 106 secondary education teachers, questionnaire was applied which were validated by five experts and its reliability was analyzed by the values obtained for Cronbach's alpha, for the digital competencies variable α = 0.861 and for the variable attitude toward the use of ICT α = 0.854. It has been shown that there is a relationship between digital competencies and the attitude toward the use of information and communication technologies in teachers of a Peruvian Public Educational Institution.

The “change of sovereignty,” the transfer of Puerto Rico to U.S. rule after Spain’s loss in the Spanish-American War of 1898, could not easily erase centuries of Spanish misrule of its island colony. Nor could it reconstruct an economy based on monocultural agricultural crops. For centuries, ranching and subsistence farming had lured settlers from the coast. Highland towns, founded in the eighteenth century under royal auspices but increasingly isolated and removed from imperial control came to define the peasant, the jı́baro, who though generally slight in stature came to loom large as the cultural backbone of Puerto Rico. Run by ministers of the Spanish monarchy and corrupt and sometimes tyrannical military governors, the island during the 1800s ineptly staggered through sequential agricultural monocultures. Sugar crops tended by coastal workers of mixed African and European backgrounds (with slavery and peonage existing side by side) yielded prominence in mid-century to large-scale coffee plantations in the mountainous interior, attracting capital and labor from the coast as well as from the Spanish homeland. By the mid-1800s U.S. interests had begun to pull on this strategically located military outpost – first through trade and then by conquest and new guardianship.