The goal of this work is to analyze and compare trajectory planners for a mobile robot in Robot Operating System (ROS), focusing on the performance of local planners on symmetric and asymmetric environments. In addition, two global planners, Dijkstra and A-star, are implemented in order to have a complete analysis and comprehension of the navigation architecture. Two local planning algorithms, Dynamic Window Approach and Timed Elastic Bands, are analyzed and compared more in depth using the mobile robot TurtleBot 3 Burger, an open-source and low-cost platform. The analyzed criteria were geometric and angular precision of the final position and orientation, time and distance of the complete trajectory, and usage of computational power. Experiments were carried out in two environments with different spatial arrangement of obstacles, with the intention of analyzing the behavior both in simulation with the Gazebo software and in the real robot. Both local planning algorithms enabled the robot to reach the target destination without any collisions, presenting the main difference in the usage of processing power.

This work explores the use of three deep learning methods for gesture recognition: Convolutional Neural Networks (CNN), Long Short-Term Memory (LSTM), and Gated Recurrent Unit (GRU) using Fast Dynamic Time Warping (FastDTW). The gestures were captured by Kinect sensors, two skeleton-based databases are used: Microsoft Research Cambridge-12 (MSRC-12) and NTU RGB+D. Also, the FastDTW technique was also employed to standardize the input size of the data. The MSRC-12 database achieved an accuracy rate of 82,36% in the test set with the CNN, the LSTM achieved an accuracy rate of 87,30% also in the test set, and in GRU the accuracy achieved in the test set was 89,34%. With the NTU RGB+D database, two evaluation methods were used: Cross-View and Cross-Subject. In the test set with Cross-View evaluation was obtained an accuracy rate of 63,53%, 55,14%, and 61,00%, with CNN, LSTM, and GRU respectively; and with the Cross-Subject evaluation method, it was achieved an accuracy rate of 66,19%, 64,43% and 60,17% in the test set on CNN, LSTM and GRU, respectively.

Traditional Visual SLAM systems, like ORB-SLAM3, often lose accuracy in dynamic environments. This work presents YOLO11-ORB-SLAM3, an enhancement to ORB-SLAM3 for dynamic scenarios, which integrates a YOLO11-based instance segmentation module to detect and exclude dynamic features from the tracking process. The system is designed to work with stereo and RGB-D cameras, and its performance was evaluated on challenging dynamic sequences of the public TUM RGB-D dataset, and also through real-world experiments on a mobile robot using a stereo camera to highlight its robustness and viability for real robotic applications. Experimental results demonstrate that the proposed system outperforms the original ORB-SLAM3, reducing the error by 93% in the public TUM dataset while preserving computational efficiency.

In the last five years, around 150 bank robbers have died in clashes with Brazilian police. This wave of violence became known as “Novo Cangaço”. Despite the gangs using explosives, rifles and .50 machine guns, this wave of terror was not classified as terrorism in Brazil. The objective of this research is to investigate this type of organised crime and its similarity to the concept of global terrorism. This is a comprehensive review of how the “Novo Cangaço” (new bandit) is understood. We investigated around 18 thousand articles and highlighted four distinct groupings to explain what terrorism is in the modern world. The findings from interviews allowed us to understand that it is only possible to classify a terrorist act under current laws if there is an attack on public events or public facilities. We interviewed police and military personnel with experience in combatting this variant of modern horror. Our conclusions indicate that this wave of violence associated with drug trafficking should be classified as terrorism. Considering these points, we believe that the “Novo Cangaço” is a form of terrorism, given its connection with drug trafficking and political movements. The use of explosives, the siege of cities, the use of hostages and violence aimed at causing terror and commotion also reinforce this definition. Such theft practices may cease to exist due to the disappearance of paper money, but the legacy will remain and serve as a lesson for those who wish to commit similar crimes. We also emphasise that this type of crime could soon inspire other gangs to commit violent crimes in Latin America.