Reconnaissance Vehicle Research Articles

Recent improvements in the novel approach to the fast detection of surface contaminations

Here, we present the idea behind a novel measurement system and the recent improvements in detecting surface contaminations using a tunable, very fast three-core quantum cascade laser (QCL) system. It is developed as a potential replacement for the old established double-wheel sampling system currently used to detect surface threats caused by hazardous, non-volatile chemical substances. The novel system design is based on an optical measurement principle, allowing standoff detection and identification, thus rendering ground contact unnecessary. One of the leading military requirements for a CBRN reconnaissance vehicle is a high marching speed; hence, this new system is designed to have an ultra-short acquisition time and an adequate spectral bandwidth for measurements in the mid-infrared (MIR). This innovative approach may replace the more cumbersome indirect detection techniques. We discuss the main advantages and evaluate possible application scenarios that we expect from this setup. Active IR backscatter spectroscopy generally permits the contactless identification of hazardous chemical substances on surfaces. Here, the design was optimized around an approximate measuring distance of decimeters. Using a monoaxial setup, the autofocus is less demanding than alternative approaches and even allows for rapid measurements of rough surfaces. We built the improved measurement system based on novel QCL modules that integrate micro-opto-electro-mechanical grating scanners (MOEMS) in an external cavity. These elaborate laser modules provide almost one kilohertz (kHz) spectral scan speeds and typically cover a spectral range of 200–300 cm-1, respectively. Furthermore, such modules achieve measurement times of as short as one millisecond per spectrum. The full spectral coverage of the system is realized by coupling several of such modules.

THE PROCEDURE FOR THE USE OF UNMANNED AERIAL VEHICLES TO CONDUCT RECONNAISSANCE ON THE GROUND IN WARTIME CONDITIONS

The article reveals the peculiarities of using unmanned aerial vehicles for reconnaissance in the field in wartime.
 The article reveals the essence and content of the use of unmanned aerial vehicles for reconnaissance, as well as the conditions and features of their effective use.
 Study of the possibilities of using unmanned to conduct reconnaissance on the ground in wartime conditions has shown that this technology has great potential to improve operational intelligence and ensuring the safety of military personnel. The advantages of using unmanned aerial vehicles for reconnaissance are obvious. They can quickly and efficiently penetrate enemy territory, collect information territory, collect information and transmit it in real time. This makes it possible to Reduce the risk to the lives of servicemen, as they do not need to go to the front line the front line to conduct reconnaissance. In addition, unmanned aerial vehicles can operate in hazardous environments, such as radioactive contamination or chemicals where humans cannot enter. The use of unmanned aerial vehicles also ensures greater accuracy and objectivity in collecting information. They are equipped with various types of sensors, such as high-resolution cameras, thermal cameras, radars, etc., which provide detailed information about the territory, enemy positions and movements. This significantly improves the quality of intelligence and allows for more informed decisions on further actions.
 In summary, research has shown that the use of unmanned aerial vehicles for reconnaissance in wartime has significant potential. They can collect information quickly, efficiently and safely, improving operational intelligence and ensuring the safety of soldiers. However, further research and development of new technologies is needed to improve the functionality and safety of unmanned aerial vehicles in warfare.

Issues of flight planning of an unmanned air reconnaissance vehicle considering the possible image distortions in accelerated motion mode

Issues of flight planning of an unmanned air reconnaissance vehicle considering the possible image distortions in accelerated motion mode

Adaptive robust control for unmanned combat platform: Obstacles avoiding and dynamic trajectory tracking

AbstractThis paper proposes an adaptive robust control scheme to deal with the uncertainty problem of unmanned combat platform. Under the constraint of the controller, the rescue vehicle aims to follow the trajectory of the reconnaissance vehicle and avoid obstacles (e.g., craters and destroyed tanks), while they eventually reach the defined target location (an accident area). First, for the control objective, the original constraints are innovatively separated into two parts: arrival constraint and tracking‐avoidance constraint. An approximate constraint‐following control substitutes for the triple problem, and the constraint‐following error is subsequently established. Second, for the control strategy, a ‐measure is introduced to measure the constraint‐following error. To ensure the tracking‐avoidance constraint and the arrival constraint can be fully satisfied by the system, an adaptive robust control is designed. Finally, for the fast time‐varying uncertainty with unknown boundary, an adaptive law is introduced to evaluate the triple tracking‐avoidance‐arrival performance. In conclusion, the main contribution of this paper is to achieve triple tracking‐avoidance arrival for unmanned combat platform, and the problem of military detection and rescue on complex battlefields can be eliminated.

FEATURES OF THE USE OF UNMANNED AIRCRAFT FOR MONITORING THE COAST LINE OF THE SEA COAST

The materials of the article reveal the features of the use of unmanned aerial vehicles for controlling the coastline of the sea coast. In the article, it is determined that in order to preserve the lives of personnel and perform tasks related to operational control and reconnaissance of the coastline of the sea coast, unmanned aerial vehicles of various types began to be actively involved.
 The purpose of the article is to reveal the features of the use of unmanned aerial vehicles for monitoring the coastline of the sea coast. The article reveals the essence and content of the use of unmanned aerial vehicles for reconnaissance of the coastal strip of the sea coast, as well as the conditions and features of their effective use according to various options for tactics.
 The main principles of using unmanned aerial vehicles as part of air reconnaissance units during control of the coastline of the sea coast are: constant high level of readiness to perform tasks; concentrating efforts on the enemy's active areas of activity; clear interaction with units of the Maritime Guard of the State Border Service of Ukraine (border units, mobile groups); high activity, decisiveness and suddenness of actions.
 The article describes the main ways of using unmanned aerial vehicles, namely: route flight; air search; accompanying the enemy. It is determined that the method of using unmanned aerial vehicles is specified by the senior chief (commander) or determined by the unit commander when making a decision to fly and use an unmanned aerial vehicle. The method of application of flight performance can be changed based on the situation in the area of responsibility in a specific period of time. At the same time, the features of the use of unmanned aerial vehicles during the day, at night, at extremely low altitudes and above the water surface are revealed.
 The article emphasizes that all flights for the purpose of controlling the coastline of the sea coast should be carried out with the maximum use of the camouflage properties of the terrain and, if possible, in the morning hours of the day. It was determined that further scientific research in this field is seen in the procedure of combining control of the coastal strip of the sea coast with reconnaissance and search for mines and explosive objects on land and water surface.

RESULTS OF THE TESTING OF THE BRDM-2L1(sb) ARMORED RECONNAISSANCE AND SURVEILLANCE VEHICLE WITH A DOUTZ BF4M1013FC DIESEL ENGINE WHILE DRIVING ON TYPICAL SECTIONS OF THE ROAD

The article analyzes the testing methodology of the BRDM-2L1(sb) armored reconnaissance vehicle with a DOUTZ BF4M1013FC diesel engine, designed to replace the BRDM carbureted vehicles with a gasoline engine currently available in the Armed Forces of Ukraine. They received a new mileage that provides assistance in performing their functions around the clock in zones with different climates. During the tests of the prototype of the BRDM-2L1(sb) armored reconnaissance vehicle with an installed DOUTZ BF4M1013FC engine. The analysis of the test results with the obtained results of parameter measurements showed that when replacing the engine, the reliability of the machine is ensured, on which the performance of combat tasks depends, directly the life of the military, which will have a positive effect on the defense capability of the country. The tests were carried out on the running section of the track, which consisted of sections of the road with an asphalt surface and a soil surface, as well as sections with marshy terrain with a large number of turns, both closed and open, on which there were ridges with a height of 30 m to 150 m and slopes from 12 º to 30 º. At the same time, obtaining the necessary information was ensured with the help of a complete set of control and measuring devices installed. As a result, it was established that the BRDM-2L1(sb) with a DOUTZ BF4M1013FC diesel engine when moving along a typical route, taking into account the varying difficulty of overcoming terrain, has an average speed of 69 kilometers per hour and a fuel consumption of 0.69 liters per 1 kilometer on a mixed-surface route which has much better performance than carbureted BRDM cars with a gasoline engine.

Usability of Perception Sensors to Determine the Obstacles of Unmanned Ground Vehicles Operating in Off-Road Environments

This article presents the essential abilities and limitations of various sensors used for object recognition in the operation environment of unmanned ground vehicles (UGVs). The use of autonomous and unmanned vehicles for reconnaissance and logistics purposes has attracted attention in many countries. There are many different applications of mobile platforms in both civilian and military fields. Herein, we introduce a newly developed manned–unmanned high-mobility vehicle called TAERO that was designed for public roads and off-road operation. Detection for unmanned mode is required in both on-road and off-road environments, but the approach to identify drivable pathway and obstacles around a mobile platform is different in each environment. Dense vegetation and trees can affect the perception system of the vehicle, causing safety risks or even collisions. The main aim was to define the limitations of the perception system in off-road environments, as well as associated challenges and possible future directions for practical applications, to improve the performance of the UGV in all-terrain conditions. Recorded datasets were used to verify vision and laser-based sensors in practical application. The future directions of work to overcome or minimize the indicated challenges are also discussed.

ПОРІВНЯЛЬНА ОЦІНКА ІСНУЮЧИХ МЕТОДІВ НАВІГАЦІЙНОГО ЗАБЕЗПЕЧЕННЯ ТА ВДОСКОНАЛЕНОГО КОМБІНОВАНОГО МЕТОДУ З ФІЛЬТРОМ ЧАСТИН РАО-БЛЕКВЕЛЛА

The analysis of the research showed that the most effective development of modern autonomous navigation software is the modernization of complexes and systems, improvement of methods and algorithms of software and hardware implementation, which will ensure the efficiency of existing equipment, relevance and reduce financial burden on weapons and military equipment. The development of a modern autonomous navigation system using modern positioning methods and algorithms is one of the priorities, because the existing systems used today, although effective, but in the future may lead to a number of problems and difficulties that will not be solved in a short time. The new solution of the scientific and applied problem, which consists in improving the mathematical and software subsystems for determining the current location of combat reconnaissance vehicles with existing information and control systems, is generalized and substantiated. The paper presents the results of an improved method of determining the current value of coordinates with a filter of Rao-Blackwell parts, which allows to determine the current coordinates of the machine with the required accuracy and conservation of the calculated resource of combat information control system. A comparative evaluation of existing navigation systems and a combined method for determining the current value of coordinates with a filter of Rao-Blackwell parts integrated into the onboard information and control system of the machine. The exact characteristics of the system for determining the current coordinates of the machine that do not exceed half the linear dimensions of the combat vehicle are established. In addition, the estimated power of the processor to perform complex arithmetic tasks in the onboard information and control system. This indicates that by reducing the cumulative error as a result of arithmetic operations in existing algorithms and in the improved method increases the accuracy of the system and reduces the estimated resource of the entire subsystem in the BICS. Keywords: on-board information and control systems, Rao-Blackwell part filter, positioning, autonomous moving object, Kalman filter.

Lunar Pit Morphology: Implications for Exploration

AbstractLunar pits are small (∼10–300 m wide) collapse features with vertical walls and sometimes overhangs. We have identified almost 300 pits, mostly in ponds of cooled impact melt inside large craters younger than ∼1 billion years. Several of these pits may provide access to lava tubes or other caves, and those in the maria expose the layering record of the top 20–100 m of basaltic lava flows. We investigated the 21 known pits outside of impact melt ponds to determine possible origins, ages, and present‐day access to the lunar subsurface. We used Lunar Reconnaissance Orbiter Narrow Angle Camera images (<2 m per pixel) to produce detailed 3D reconstructions of six pit interiors. We evaluated the general morphology and geologic context of all twenty‐one. While four pits have contexts suggestive of lava tubes, the majority are ambiguous, although all occur in or near the maria. We also propose that pit formation is an ongoing process, as the degree of degradation of a pit is unrelated to the age of the host terrain. Much of the original volume of most pits is now filled with debris, but some exhibit significant overhangs and may have present‐day cave access. Viewing pit walls and floors, even from the rims, requires navigating steep slopes of loose material. Since the floors are also covered with rough debris piles, we recommend simple flying vehicles for initial reconnaissance.

Lyapunov-based Robust Adaptive Configuration of the UAS-S4 Flight Dynamics Fuzzy Controller

AbstractIn tandem with the fast-growing demand for Unmanned Aerial Vehicles (UAVs) for surveillance and reconnaissance, advanced controllers for these critical systems are needed. This paper proposes a flight dynamics controller design that considers various uncertainties for the Hydra Technologies UAS-S4 Ehécatl. In order to be realistic, in addition to flight dynamics nonlinearities, three main sources of uncertainties are considered, as those caused by unknown controller’s parameters, modeling errors, and external disturbances. A Robust adaptive fuzzy logic controller is designed, in charge of nonlinear flight dynamics in presence of a variety of uncertainties. The nonlinear flight dynamics is modeled based on the Takagi-Sugeno method relying on the soft association of local linear models. Since this controller is model-based, an optimal reference model is defined, which is stabilised by the Linear Quadratic Regulator procedure. A fuzzy logic controller is then designed for the nonlinear model. Lastly, with the aim to handle the uncertainties, the gains of the fuzzy controller are reconfigured, and are continuously adjusted by Lyapunov-based robust adaptive laws. The performance of the UAS-S4 Robust adaptive fuzzy logic controller is evaluated in terms of lateral and longitudinal flight dynamics stabilisation, and the reference model state variables tracking under various uncertainties.

Application of area monitors and scintillating detectors in the development of CBRN defense reconnaissance vehicles

This study describes the use of ionizing radiation detectors in a Brazilian Army reconnaissance vehicle (RV), used in area monitoring actions based on the occurrence of a radiological event. Two scintillating detectors, NaI and LaBr3, were used to carry out field measurements of surveying for different distances from a simulated detector position in the vehicle, in order to compare the energy spectra obtained in each measurement system. The Brazilian Army Technological Center (Centro Tecnológico do Exército - CTEx) region was chosen to carry out the measurements. The meteorological information was annotated to verify the conditions into which the experimental apparatus would be submitted. The results suggest that both the NaI and LaBr3 scintillating detector could be used in radiological emergency response RV, offering satisfactory responses in the gamma radiation detection. However, the NaI detector was chosen considering the wide network of technical assistance and its low operational cost. The relevance of this investigation shows the importance of planning responses in emergency situations and the influence of efficient instrumentation in the measurement processes.

UAV Path Planning for Reconnaissance and Look-Ahead Coverage Support for Mobile Ground Vehicles.

Path planning of unmanned aerial vehicles (UAVs) for reconnaissance and look-ahead coverage support for mobile ground vehicles (MGVs) is a challenging task due to many unknowns being imposed by the MGVs’ variable velocity profiles, change in heading, and structural differences between the ground and air environments. Few path planning techniques have been reported in the literature for multirotor UAVs that autonomously follow and support MGVs in reconnaissance missions. These techniques formulate the path planning problem as a tracking problem utilizing gimbal sensors to overcome the coverage and reconnaissance complexities. Despite their lack of considering additional objectives such as reconnaissance coverage and dynamic environments, they retain several drawbacks, including high computational requirements, hardware dependency, and low performance when the MGV has varying velocities. In this study, a novel 3D path planning technique for multirotor UAVs is presented, the enhanced dynamic artificial potential field (ED-APF), where path planning is formulated as both a follow and cover problem with nongimbal sensors. The proposed technique adopts a vertical sinusoidal path for the UAV that adapts relative to the MGV’s position and velocity, guided by the MGV’s heading for reconnaissance and exploration of areas and routes ahead beyond the MGV sensors’ range, thus extending the MGV’s reconnaissance capabilities. The amplitude and frequency of the sinusoidal path are determined to maximize the required look-ahead visual coverage quality in terms of pixel density and quantity pertaining to the area covered. The ED-APF was tested and validated against the general artificial potential field techniques for various simulation scenarios using Robot Operating System (ROS) and Gazebo-supported PX4-SITL. It demonstrated superior performance and showed its suitability for reconnaissance and look-ahead support to MGVs in dynamic and obstacle-populated environments.

ИССЛЕДОВАНИЕ ВЛИЯНИЯ СЛОЖНЫХ УСЛОВИЙ ПОЖАРНОЙ ОБСТАНОВКИ НА КАЧЕСТВО НАБЛЮДЕНИЯ И БЕЗОПАСНОСТЬ ПОЛЁТА БЛА

Aviation monitoring of fires with the help of unmanned aerial vehicles (UAVs), in particular,forest ones, during which the search for various objects of interest is carried out: people, cars,etc., is one of the most effective measures to reduce the level of possible losses. In this paper, weconsider approaches to the formation of algorithms for processing and improving images obtainedin the process of monitoring the fire situation, based on the use of neural networks, as well asimage filtering algorithms, in order to search for various objects of interest. Fire monitoring usingan UAV is a two-criteria task: there is a need to protect the device from the thermal effects of thefire as much as possible, as well as to maximize the observability, which can be achieved by reducingthe altitude of the flight. This paper presents the empirical models developed by the authors forthe flight safety of an unmanned aerial vehicle and the observability of objects of interest in theprocess of monitoring the fire situation. The proposed models allow us to take into account thefeatures of the monitoring conditions, such as the priority of detecting the object of interest to thesecurity of the reconnaissance vehicle itself, air humidity, terrain and type of terrain, time of day,and so on. An example of the application of the contrast model is considered on the example of thesearch and detection of the "letter"label. On the basis of the conducted experiment on the recognitionof the mark in the smoke, the analysis of the proposed models is carried out, the quantitativeresults are given. The paper describes the criteria for the optimal choice of the altitude of theflight of the device over the observed scene, which are formed on the basis of the base of expertassessments, as well as the proposed models of the observability and safety of the UAV flight. Dependingon the target search task, the optimality criterion for choosing the UAV flight altitudeover the observed scene may vary.

Application of unmanned aircraft for detection of chemical situation

Hybrid conduct, efficiency and rapidity of hostilities depend on many factors, including the ability to constantly receive information from the battlefield, time to make decisions and clear implementation of tasks. This can be achieved by increasing the efficiency of all types of reconnaissance, including chemical. The article substantiates the prospects of using unmanned aerial vehicles to detect chemical contamination during chemical reconnaissance by radiation, chemical and biological reconnaissance units. It is established that the probability of detecting a chemical situation depends on the degree of training, physical endurance, psychological stability and fatigue of reconnaissance patrol personnel, technical characteristics of devices installed on reconnaissance vehicles, speed of reconnaissance vehicle or pedestrian patrol in hard-to-reach places. The capabilities of radiation, chemical and biological reconnaissance units to quickly detect chemical conditions are significantly enhanced by conducting air reconnaissance by unmanned aerial vehicles and equipping ground and air reconnaissance devices with devices that identify both combat poisons and hazardous chemicals. It is shown that the use of UAVs with a set of passive infrared spectrometry and automated real-time data transmission system is currently the best option, as the probability of detecting war poisons (hazardous chemicals) in a given area increases, and time for chemical reconnaissance - decreases, which, accordingly, increases the response time of units to a chemical threat. To install modern chemical reconnaissance equipment, in particular passive Fourier-ICS devices, helicopter-type UAVs must meet the following requirements: length - up to 5 m, weight of useful equipment - up to 50 kg, cruising speed - 150 km / h. In addition, it decreases moral exhaustion and the risk of personnel damage. The probable order of application of unmanned aerial vehicles of helicopter type equipped with modern devices is given.

Advancing Prehospital Combat Casualty Evacuation: Patients Amenable to Aeromedical Evacuation via Unmanned Aerial Vehicles.

The U.S. military currently utilizes unmanned aerial vehicles (UAVs) for reconnaissance and attack missions; however, as combat environment technology advances, there is the increasing likelihood of UAV utilization in prehospital aeromedical evacuation. Although some combat casualties require life-saving interventions (LSIs) during medical evacuation, many do not. Our objective was to describe patients transported from the point of injury to the first level of care and characterize differences between patients who received LSIs en route and those who did not. We conducted a retrospective review of the records of traumatically injured patients evacuated between January 2011 and March 2014. We compared patient characteristics, complications, and outcomes based on whether they had an LSI performed en route (LSI vs. No LSI). We also constructed logistic regression models to determine which characteristics predict uneventful flights (no en route LSI or complications). We examined 1,267 patient records; 47% received an LSI en route. Most patients (72%) sustained a blast injury and injuries to the extremities and head. Over 78% experienced complications en route; the LSI group had higher rates of complications compared to the No LSI group. Logistic regression showed that having a blunt injury or the highest abbreviated injury scale (AIS) severity score in the head/neck region are significant predictors of having an uneventful flight. Approximately half of casualties evaluated in our study did not receive an LSI during transport and may have been transported safely by UAV. Having a blunt injury or the highest AIS severity score in the head/neck region significantly predicted an uneventful flight.

ЗАВДАННЯ РОЗВІДУВАЛЬНО-УДАРНОГО БЕЗПІЛОТНОГО АВІАЦІЙНОГО КОМПЛЕКСУ «BAYRAKTAR TB2»

The article analyzes the world experience of using reconnaissance and strike unmanned aerial vehicles in operations of recent decades, experience and conditions of use of reconnaissance and strike unmanned aerial vehicles «Bayraktar TB2» in military conflicts. Based on the results of the analysis, conclusions were made on the compliance of reconnaissance and strike unmanned aerial vehicles «Bayraktar TB2» with modern requirements. The conditions in which the reconnaissance and strike unmanned aerial vehicle complex «Bayraktar TB2» can be used are determined, the characteristics that can positively and negatively affect its use and the tasks it can perform are considered. The threats that should be taken into account when planning the combat use of reconnaissance and strike unmanned aerial vehicles «Bayraktar TB2» are considered. The experience of using «Bayraktar TB2» reconnaissance and unmanned aerial vehicles in the armed conflict in the Syrian Arab Republic is analyzed. The peculiarities of the use of troops (forces) in the operational zone in eastern Ukraine are analyzed, the main tasks and possible goals of reconnaissance and strike unmanned aerial vehicles during the operation of groups of troops (forces) in eastern Ukraine are determined. Possible options for involving «Bayraktar TB2» reconnaissance and unmanned aerial vehicles in reconnaissance and destruction of enemy objects (targets) at various stages of hostilities are considered. It was concluded that the importance and necessity of using reconnaissance and strike unmanned aerial vehicles «Bayraktar TB2» in repelling the offensive of enemy strike groups. Keywords: reconnaissance and strike unmanned aerial vehicles, unmanned aerial vehicles, combat applications, fire damage, main tasks, objects of destruction.

Způsob stanovení požadavků na bezosádkové pozemní vozidla pro vedení průzkumu a sledování

The article deals with the possible determination of obtaining information method and data to find the requirements for unmanned ground vehicles for reconnaissance and surveillance units. The article emphasizes the specification of general capabilities and features of reconnaissance and surveillance, which serve to define the requirements for unmanned ground vehicles. For the same reason, the article examines the individual environments that may affect the determination of requirements. Using the example of methods using cognitive maps, the mutual correlation of the researched issue is shown.

Actions of nbc reconnaissance units during search for small sites of radioactive contamination

The optimal ways of searching for small sites of radioactive contamination, so-called "dead" zones, which are formed in case of destruction of dangerous objects that use, process, store and transport radioactive agents during conducting reconnaissance by the NBC units, are analyzed. The following research methods have been applied: bibliographic, analytical, systematic and informational approach. The following ways of searching (reconnaissance) of contaminated sites of the area are considered: the zigzag locate technique, the boustrophedon technique, the classical and rectangular spiral technique and the star survey technique. The length of the route was determined and the optimal parameters for their carrying out under certain conditions were established. The zigzag method (29-52%) is found to be the most effective, while the star survey technique is fast but ineffective. The probability of finding contaminated sites based on the height of the location of the detection unit and the energy of γ-quanta of radioisotopes, which are formed during the destruction of a nuclear reactor, disruption of nuclear and thermonuclear ammunition, is calculated. Increasing the probability of finding depends on the distance between the routes, their length, as well as the specifications of the radiation reconnaissance devices. Removal of the detection unit outside the reconnaissance vehicle increases the search efficiency, which depends on the specifications of the detection units of radiation reconnaissance devices. It is shown that the use of aerial reconnaissance equipment significantly increases the survey area and the efficiency of detecting a radiation situation by productivity, since the detection unit is located at a significantly higher altitude than 3 m. Requirements for technical specifications of unmanned aerial vehicles of radiation reconnaissance are formulated. It is determined that in order to fully accomplish the task of radiation reconnaissance, it is necessary to use the means of aerial and ground radiation reconnaissance in a complex way, complementing one tool with another.

Cooperative multi‐agent sweep coverage control for unknown areas of irregular shape

The study solves multi-agent cooperative control problems of covering irregularly-shaped unknown areas. A sweep coverage motion scheme is proposed: the agents are arranged in a row across the area and sweep through. The formation is flexible thus the agents can be scattered across the widest part and can queue up to pass through the narrowest portion. This allows the agents to cover the region by collectively passing through it only once, which may help to improve the survivability of reconnaissance vehicles. A distributed second-order control law is designed by modelling the agents as point masses in planar space. The approach is inspired by the motion of a string of balls connected by springs, thus virtual elastic force and potential field are applied to the agents, which introduces non-linearity to the system. Complete coverage as well as collision avoidance among agents and borders are guaranteed by parameter constraints that provided and validated via theoretical deduction and numerical simulations. Compared with the existing unknown-area coverage methods by randomly exploring the area, the proposed one yields more regular motion paths. Limitations of the work and future research directions are finally concluded.

Engine-Control Impact on Energy Balances for Two-Stroke Engines for 10–25 kg Remotely Piloted Aircraft

The rapid expansion of the market for remotely piloted aircraft (RPA) includes a particular interest in 10–25 kg vehicles for monitoring, surveillance, and reconnaissance. Power-plant options for these aircraft are often 10–100 cm3 internal combustion engines (ICEs). The present study builds on a previous study of loss pathways for small, two-stroke engines by quantifying the trade space among energy pathways, combustion stability, and engine controls. The same energy pathways are considered in both studies—brake power, heat transfer from the cylinder, short circuiting, sensible exhaust enthalpy, and incomplete combustion. The engine controls considered in the present study are speed, equivalence ratio, combustion phasing (ignition timing), cooling-air flow rate, and throttle. Several options are identified for improving commercial-off-the-shelf (COTS)-engine efficiency and performance for small, RPA. Shifting from typical operation at an equivalence ratio of 1.1–1.2 to lean operation at an equivalence ratio of 0.8–0.9 results in a 4% (absolute) increase in fuel-conversion efficiency at the expense of a 10% decrease in power. The stock, linear timing maps are excessively retarded below 3000 rpm, and replacing them with custom spark timing improves ease of engine start. Finally, in comparison with conventional-size engines, the fuel-conversion efficiency of the small, two-stroke ICEs improves at throttled conditions by as much as 4–6% (absolute) due primarily to decreased short-circuiting. When no additional short-circuiting mitigation techniques are employed, running a larger engine at partial throttle may lead to an overall weight savings on longer missions. A case study shows that at 6000 rpm, the 3W-55i engine at partial throttle will yield an overall weight saving compared to the 3W-28i engine at wide-open throttle (WOT) for missions exceeding 2.5 h (at a savings of ∼5 g/min).