Unmanned aerial vehicles (UAVs) are increasingly attracting investment and development attention from many countries all over the world due to their great advantages. However, one of the biggest challenges for researchers is the problem of supplying energy to UAVs to ensure they can operate for a longer time. Especially in the case of rotary wings, they consume more energy than other UAV types as the motors need to spend a lot of energy to operate in order to overcome the gravity of the earth. The article aims to research power supply, energy consumption on UAVs, and a method of taking advantage of external energy sources to provide power for the operation of UAVs and discuss UAVs’ structure, categories, and control. Two experiments were conducted separately to evaluate the energy consumption of UAVs and the energy conversion from external energy sources to electrical energy. A test bench was designed to evaluate and determine the maximum efficiency using regenerative braking mode. The measuring device was manufactured to measure the necessary parameters to calculate the energy consumption and performance of the system. Experimental numerical results show that energy conversion from external sources is one of methods that can help increase the flight time of the UAV.
In recent decades, the trend of using zero-emission vehicles has been constantly evolving. This trend brings about not only the pressure to develop electric vehicles (EVs) or hybrid electric vehicles (HEVs) but also the demand for further developments in battery technologies and safe use of battery systems. Concerning the safe usage of battery systems, Battery Management Systems (BMS) play one of the most important roles. A BMS is used to monitor operating temperature and State of Charge (SoC), as well as protect the battery system against cell imbalance. The paper aims to present hardware and software designs of a BMS for unmanned EVs, which use Lithium multi-cell battery packs. For higher modularity, the designed BMS uses a distributed topology and contains a master module with more slave modules. Each slave module is in charge of monitoring and protecting a multi-cell battery pack. All information about the state of each battery pack is sent to the master module which saves and sends all data to the control station if required. Controlled Area Network (CAN) bus and Internet of Things technologies are designed for requirements from different applications for communications between slave modules and the master module, and between the master module and control station.
The paper describes the influence of power electronics, energy processing, and emergency radio systems (ERS) immunity testing on onboard aircraft equipment and ground stations providing air traffic services. The implementation of next-generation power electronics introduces potential hazards for the safety and reliability of aircraft systems, especially the interferences from power electronics with high-power processing. The paper focuses on clearly identifying, experimentally verifying, and quantifiably measuring the effects of power electronics processing using switching modes versus the electromagnetic compatibility (EMC) of emergency radio systems with electromagnetic interference (EMI). EMI can be very critical when switching power radios utilize backup receivers, which are used as aircraft backup systems or airport last-resort systems. The switching power electronics process produces interfering electromagnetic energy to create problems with onboard aircraft radios or instrument landing system (ILS) avionics services. Analyses demonstrate significant threats and risks resulting from interferences between radio and power electronics in airborne systems. Results demonstrate the impact of interferences on intermediate-frequency processing, namely, for very high frequency (VHF) radios. The paper also describes the methodology of testing radio immunity against both weak and strong signals in accordance with recent aviation standards and guidance for military radio communication systems in the VHF band.
This paper deals with the analyses of batteries used in current military systems to power the electric drives of military vehicles. The article focuses on battery analyses based on operational data obtained from measurements rather than analyses of the chemical composition of the tested batteries. The authors of the article used their experience from the development test-laboratory of military technology. This article presents a comparative analysis of existing and promising technologies in the field of energy storage and buffering for military electric vehicles. The overview of these technologies, including the design, operating principles, advantages, and disadvantages, are briefly presented to produce theoretical comparative analyses. However, this article mainly focuses on the experimental verification of operational ability in varied conditions, as well as the comparison and analysis of these results. The main part of the article provides more experimental studies on technologies of energy storage and buffering using the results of several experiments conducted to demonstrate the behavior of each technology in different working conditions. The output parameters, as well as the state of charge of each technology’s samples, were surveyed in various temperatures and loading characteristics. The results presented in this paper are expected to be useful for optimizing the selection of energy storage and buffering solutions for military electric vehicles in different applications and functional environments.
Detecting the structural integrity of composite material used in an airframe includes passive non-destructive testing (NDT) and active electrical impendence tomography (EIT). EIT benefits enhance real-time response and accuracy but require pragmatic approaches to analysis of electrode errors from faulty or non-responsive readings. Non-functional connections of measuring electrodes often occur during onboard aircraft operations for various reasons such as deterioration. The deterioration of the electrode impedance impacts the quality of the EIT reconstructed image. The paper compares different EIT methods and proposes SURface Fault EIT (SURFEIT). The proposed SURFEIT techniques that detect and compensate for faults are verified and evaluated using models with different location of inside damages. Results prove the effectiveness of SURFEIT techniques, when the number of faulty electrodes is up to one-fourth of the total electrodes. The biggest benefit of the SURFEIT techniques is that they do not require any additional simulation work, lead to significant reduction of computation time, and afford very fast indications of damage locations.