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This research focuses on the dynamic response analysis of a quadcopter arm without an adapter mounted and with aerodynamic profile adapters mounted to enhance drone performance. Nine different adapters were simulated to assess their impact on the arm’s dynamic behavior during various motor operating regimes. The pressure force distribution from the airflow around the quadcopter arm was analyzed to determine the optimal adapter configuration. Numerical simulations revealed the best geometry for the adapter, which significantly reduced maximum displacement amplitudes compared to the non-adapter arm. The study also examined the effects of static imbalance from the rotor-propeller assembly, leading to the calculation of an eccentricity value of 0.022 mm for inertial force application. Experimental tests validated the numerical findings, with laser vibrometer measurements confirming improved dynamic responses with Adapter 8 across most operating regimes. Overall, the study shows the advantages of using better aerodynamic designs in quadcopter arms to improve stability and performance, contributing to advancements in drone technology through improved structural designs.

The purpose of prosthetic devices is to reproduce the angular-torque profile of a healthy human during locomotion. A lightweight and energy-efficient joint is capable of decreasing the peak actuator power and/or power consumption per gait cycle, while adequately meeting profile-matching constraints. The aim of this study was to highlight the dynamic characteristics of a bionic leg with electric actuators with rotational movement. Three-dimensional (3D)-printing technology was used to create the leg, and servomotors were used for the joints. A stepper motor was used for horizontal movement. For better numerical simulation of the printed model, three mechanical tests were carried out (tension, compression, and bending), based on which the main mechanical characteristics necessary for the numerical simulation were obtained. For the experimental model made, the dynamic stresses could be determined, which highlights the fact that, under the conditions given for the experimental model, the prosthesis resists.

This paper presents mathematical models to estimate the kinematics and dynamics of wheeled and tracked robots. The models account for the physical–mechanical characteristics of the ground, the influence of the center of gravity displacement on the cornering moment of resistance, and the influence of the interaction of the crawler with the roadway. The results of the models are characterized by defining computational relationships for a robot’s equations of motion, longitudinal forces, transverse forces, and resistive turning moments generated via longitudinal forces and transverse forces.

The aim of the paper is to validate the analytical–numerical analysis method regarding the operating regime of the propellers of a quadcopter. The research aims to mark the flow areas whose numerical results differ from the experimental ones and to investigate the possible reasons for the discrepancies between the values. The paper presents the determination of the air velocity produced by the rotational movement of a quadcopter propeller for a stationary position of the drive motor. The velocities were determined both experimentally at various points located below the propeller plane using hot-wire anemometric probes and numerically using a time-lapse simulation with a rotating sliding table. The numerical simulations carried out consisted of the determination of the time variation of the velocity distribution developed by the propeller in the rotational movement for the different operating (power) cycles of the engine. In addition, a technique that utilizes reverse engineering to determine the propeller profile, the anemometric probe calibration, and the average velocity values measured at various points below the propeller plane for engine operating regimes that range from 60 to 90% are also presented.

Burning forests, petrochemical installations and material warehouses generate very large fields and thermal gradients, which means human intervention to extinguish the fire is greatly limited. For that reason, the use of robots is recommended, but because of high temperature, they have to be equipped with protective thermal shields. This article is an analytical, numerical, and experimental study on how a double-wall, stainless steel heat shield influenced the thermal gradients acting on a firefighting robot. Following the analytical analysis at a maximum temperature of 350 °C, it was possible to identify the parameters that must be measured to be correlated with those from finite element analysis (FEM) analysis. Experimental tests showed a decrease in temperature behind the shield due to the stainless steel and the double-walled. The main conclusions and contributions of this paper consist of the realization of a finite difference model with FEM that takes into account conduction, convection, and radiation. It also highlights the benefits of using a multilayer shield.

To protect the personnel of the intervention units operating in high-risk areas, it is necessary to introduce (autonomous/semi-autonomous) robotic intervention systems. Previous studies have shown that robotic intervention systems should be as versatile as possible. Here, we focused on the idea of a robotic system composed of two vectors: a carrier vector and an operational vector. The proposed system particularly relates to the carrier vector. A simple analytical model was developed to enable the entire robotic assembly to be autonomous. To validate the analytical-numerical model regarding the kinematics and dynamics of the carrier vector, two of the following applications are presented: intervention for extinguishing a fire and performing measurements for monitoring gamma radiation in a public enclosure. The results show that the chosen carrier vector solution, i.e., the ground vehicle with six-wheel drive, satisfies the requirements related to the mobility of the robotic intervention system. In addition, the conclusions present the elements of the kinematics and dynamics of the robot.

Recently, additive manufacturing (AM) processes have expanded rapidly in various fields of the industry because they offer design freedom, involve layer-by-layer construction from a computerized 3D model (minimizing material consumption), and allow the manufacture of parts with complex geometry (thus offering the possibility of producing custom parts). Also, they provide the advantage of a short time to make the final parts, do not involve the need for auxiliary resources (cutting tools, lighting fixtures or coolants) and have a low impact on the environment. However, the aspects that make these technologies not yet widely used in industry are poor surface quality of parts, uncertainty about the mechanical properties of products and low productivity. Research on the physical phenomena associated with additive manufacturing processes is necessary for proper control of the phenomena of melting, solidification, vaporization and heat transfer. This paper addresses the relevant additive manufacturing processes and their applications and analyzes the advantages and disadvantages of AM processes compared to conventional production processes. For the aerospace industry, these technologies offer possibilities for manufacturing lighter structures to reduce weight, but improvements in precision must be sought to eliminate the need for finishing processes.