High Maneuverability Research Articles

Reinforcement learning framework for UAV-based target localization applications

Smart environmental monitoring has gained prominence, where target localization is of utmost importance. Employing UAVs for localization tasks is appealing owing to their low-cost, lightweight, and high maneuverability. However, UAVs lack the autonomy of decision-making if met with uncertain situations. Therefore, reinforcement learning (RL) can introduce intelligence to UAVs, where they learn to act based on the presented situation. Existing works focus on UAV trajectory optimization, navigation, and target tracking. These methods are application-specific and cannot be adapted to localization tasks since they require prior knowledge of the target. Moreover, the current RL-based autonomous target localization systems are lacking since- 1) they must keep track of all visited locations and their corresponding readings, 2) they require retraining when encountering new environments, and 3) they are not scalable since the agent's movement is limited to slow speeds and for specific environments. Therefore, this work proposes a data-driven UAV target localization system based on Q-learning, which employs tabular methods to learn the optimal policy. Deep Q-network (DQN) is introduced to enhance the RL model and alleviate the curse of dimensionality. The proposed models enable smart decision-making, where the sensory information gathered by the UAV is exploited to produce the best action. Moreover, the UAV movement is modeled based on motion physics, where the actions correspond to linear velocities and heading angles. The proposed approach is compared with different benchmarks, where the results indicate that a more efficient, scalable, and adaptable localization is achieved, irrespective of the environment or source characteristics, without retraining.

DIGITAL HERITAGE AND PRESERVATION: AERIAL PHOTOGRAMMETRY AND LIDAR APPLIED TO THE MAPPING OF KAPAYUWANAN, INDIGENOUS PAIWAN SETTLEMENTS, TAIWAN

Abstract. This paper discusses the application of UAV and Terrestrial photogrammetry and LiDAR for mapping Taiwanese indigenous Settlements. The relics of Taiwanese indigenous settlements with thousands history are widely distributed in deep forestry mountains with inconvenient transportation. Kapayuwanan is the original place of paiwan indigenous people. Firstly, UAV photogrammetry is applied for mapping supayuan settlement of 8 hectares and those stone houses invisible under dense forest are drawn by in-site investigation. Then UAV photogrammetry and LiDAR are used to document the larger area of Kapayuwanan of 36 hectares and terrestrial Lidar for the area of 1.2 hectares sorted out. It can not only obtain the accurate topography, landscape with architecture but also reveal the hidden settlements, such as roads, stone slab houses, irrigation landscape under the dense forest. Accuracy mapping is fundamental for future preservation planning and virtual conservation.Shaping the future is from revealing the Past. That is crucial to document, understand, and preserve the precious cultural heritage. Documenting with immediacy, high resolution, high manoeuvrability become possible because of the rapid developments of digital technologies in the recent two decades. It’s astonishing, in the case of Taiwanese indigenous archaeological settlements sites, UAV photogrammetry and Lidar can successfully reveal the relics of stone slab houses in such a sever site – steep slopes, dense forestry with plantation in biodiversity. The reveal of settlements with reclaimed landscape verifies oral transmission of indigenous people as well . Digital technologies support the contention of archaeology, anthropology, heritage preservation, and cultural landscape, indispensable for revealing the past and shaping the future.

Design and Fabrication of a Fiber Bragg Grating Shape Sensor for Shape Reconstruction of a Continuum Manipulator.

Continuum dexterous manipulators (CDMs) are suitable for performing tasks in a constrained environment due to their high dexterity and maneuverability. Despite the inherent advantages of CDMs in minimally invasive surgery, real-time control of CDMs' shape during nonconstant curvature bending is still challenging. This study presents a novel approach for the design and fabrication of a large deflection fiber Bragg grating (FBG) shape sensor embedded within the lumens inside the walls of a CDM with a large instrument channel. The shape sensor consisted of two fibers, each with three FBG nodes. A shape-sensing model was introduced to reconstruct the centerline of the CDM based on FBG wavelengths. Different experiments, including shape sensor tests and CDM shape reconstruction tests, were conducted to assess the overall accuracy of the shape-sensing. The FBG sensor evaluation results revealed the linear curvature-wavelength relationship with the large curvature detection of 0.045 mm and a high wavelength shift of up to 5.50 nm at a 90° bending angle in both the bending directions. The CDM's shape reconstruction experiments in a free environment demonstrated the shape-tracking accuracy of 0.216 ± 0.126 mm for positive/negative deflections. Also, the CDM shape reconstruction error for three cases of bending with obstacles was observed to be 0.436 ± 0.370 mm for the proximal case, 0.485 ± 0.418 mm for the middle case, and 0.312 ± 0.261 mm for the distal case. This study indicates the adequate performance of the FBG sensor and the effectiveness of the model for tracking the shape of the large-deflection CDM with nonconstant-curvature bending for minimally invasive orthopedic applications.

Inverse Kinematics Solution Method of an Adaptive Piecewise Geometry for Cable-Driven Hyper-Redundant Manipulator

Abstract Cable-driven hyper-redundant manipulator (CDHM) with flexible and compliant configuration has high maneuverability in a tight space owing to its multiple degrees of freedom (DOFs). However, an increase in the DOFs of the manipulator makes it very challenging to solve its inverse kinematics. The present work proposes a novel adaptive piecewise geometry method to solve the inverse kinematics of the CDHM. The corresponding computation efficiency will be much lower for traditional methods, i.e., the generalized inverse of the Jacobian matrix and artificial neural network method. When the end-effector of the manipulator is required to move with a larger range, Joint angle physical limit needs to be considered and the proposed method can select the optimal arc configuration to solve the inverse kinematics aiming at reducing joint overrun. An adaptive adjustment coefficient is further introduced to optimize the double-arc configuration so that joint motion is more reasonable as well as avoiding singular configuration. The geometry and joint parameters solved with the proposed novel method are then compared to those of the existing method with the same desired target position to verify the effectiveness of the proposed novel method. Finally, a 12-DOFs hyper-redundant manipulator physical prototype is built, and corresponding experimental results show that with the novel solution method, the manipulator end can precisely reach the expected target position with significantly less computational complexity, which is beneficial to improve real-time control efficiency of the CDHM in practical applications.

The investigation of lateral/heading characteristics and the influence of jet control at high attack angle

When the aircraft does high maneuvers at a high attack angle, the rapid transition of flight state induces a series of complex flow phenomena such as flow separation and vortex breakdown, leading to a series of uncommanded motions such as self-excited roll oscillation, which brings great danger to the flight of the aircraft. Therefore, it is important to investigate the mechanism of this phenomenon and suppress it. In this paper, the numerical method is based on Lattice Boltzmann Method (LBM) and Large Eddy Simulation (LES) for the SACCON standard flying-wing layout aircraft model. The accuracy of the numerical method is validated by comparing the simulation results of aerodynamic loads at different attack angles with the experimental results. Then the phenomena of the vortex breakdown and shedding at different roll angles and sideslip angles at high attack angles are analyzed, and the relationship between the jet flow coefficient and the control moment is obtained by adding the jet flow to the fuselage. Finally, the rolling motion of the aircraft is simulated in the dynamic simulation. The simulation results show that the model generates self-excited roll oscillations around a nonzero mean angle at high attack angles. The dynamic numerical simulation based on the LBM method can be an effective complementary tool for the study of the dynamic characteristics of the aircraft with a high attack angle.

Motion Parameters Estimation and HRRP Reconstruction of Maneuvering Weak Target for Wideband Radar Based on SKT-ELVD

Compared with narrowband radars, the high-resolution range profile (HRRP) acquired by wideband radars contain abundant target information that is useful for detection and recognition. However, more and more threatening targets are of low observability and high maneuverability. Therefore, reconstructing HRRPs of maneuvering weak targets from low signal-to-noise ratio (SNR) echoes is a significant but challenging problem. To estimate motion parameters and reconstruct high-SNR HRRP, this paper proposes a long-time coherent integration (LTCI) algorithm based on subband keystone transform (SKT) and extended Lv's distribution (ELVD). In this paper, the range-spread target (RST) assumption is applied in the LTCI processing. Moreover, the proposed SKT-ELVD operations have excellent performance on range migration (RM) correction and integration gain. The proposed algorithm can be of effectiveness in lower SNR conditions, since more energy of target's echo can be accumulated. Theoretical results are initially supported by sufficient simulation examples. Finally, the validity of the proposed algorithm is confirmed by experimental data.

Challenges for pure uniportal robotic-assisted thoracoscopic surgery

: In the realm of video-assisted thoracic surgery, pure uniportal robotic-assisted thoracic surgery, also known as U-RATS, is the most cutting-edge and up-to-date technology. A single incision is made through the intercostal space (ICS); the average length of the incision is between 3 and 4 centimetres, and a robotic camera, robotic dissecting equipment, and robotic staplers are utilized during the procedure. A thoracic surgeon controls the robotic system’s patient cart from a master console; the patient cart is linked to three instrumental arms and a camera arm through electrical cables and robotic fibers. The ribs are not spread apart during this procedure. The first pure uniportal robotic-assisted thoracic surgery (U-RATS) lobectomy was performed in the world by Diego Gonzalez Rivas with the Da Vinci Xi system in September 2021. Robotic-assisted thoracic surgery has better vision, more static movement, higher maneuverability, and more capability during lymph node dissection. In terms of feasibility, safety, oncological outcomes, and the postoperative recovery period, the pure uniportal approach utilizing robotic technology would be a significant improvement. The role of nurses in U-RATS begins even before the surgical procedure itself. During the preoperative phase, nurses work closely with the surgical team to prepare the patient for the procedure, including obtaining informed consent, conducting preoperative assessments, and ensuring that the patient is mentally and physically prepared for surgery. In this article, we discussed the current challenges that the uniportal RATS technique is encountering all around the world in the field of thoracic surgery.

A constrained cooperative guidance algorithm based on gray wolf optimization against highly maneuvering target

This paper investigates the problem of cooperative guidance of two pursuers against an evader equipped with higher maneuverability. The goal is that the distance between the Evader and at least one of the pursuers becomes less than a predetermined threshold at the end of flight time. To achieve this goal, firstly, the roles of pursuers are divided into two units, which include (1) pursuing the Evader and (2) Observing the Evader’s escape space. Secondly, a new cooperative guidance algorithm based on the separation of roles of the pursuers is proposed and formulated into a constrained nonlinear model predictive control problem. An objective function with time-variant weighting factors is presented to evaluate the constrained guidance commands. The proposed guidance algorithm uses a gray wolf-based optimization algorithm to calculate the guidance commands.

Nonlinear robust adaptive control for bidirectional stabilization system of all-electric tank with unknown actuator backlash compensation and disturbance estimation

Since backlash nonlinearity is inevitably existing in actuators for bidirectional stabilization system of all-electric tank, it behaves more drastically in high maneuvering environments. In this work, the accurate tracking control for bidirectional stabilization system of moving all-electric tank with actuator backlash and unmodeled disturbance is solved. By utilizing the smooth adaptive backlash inverse model, a nonlinear robust adaptive feedback control scheme is presented. The unknown parameters and unmodelled disturbance are addressed separately through the derived parametric adaptive function and the continuous nonlinear robust term. Because the unknown backlash parameters are updated via adaptive function and the backlash effect can be suppressed successfully by inverse operation, which ensures the system stability. Meanwhile, the system disturbance in the high maneuverable environment can be estimated with the constructed adaptive law online improving the engineering practicality. Finally, Lyapunov-based analysis proves that the developed controller can ensure the tracking error asymptotically converges to zero even with unmodeled disturbance and unknown actuator backlash. Contrast co-simulations and experiments illustrate the advantages of the proposed approach.

An adaptive multi-objective joint optimization framework for marine hybrid energy storage system design considering energy management strategy

The electric propulsion ship with the hybrid energy storage system (HESS) has environmental friendliness and significant advantages in terms of low fuel consumption. Due to the high maneuverability and load fluctuation of vessels, marine HESS design problem is nonlinear and multi-objective. Aiming at HESS design problem with complex working conditions during vessel practical operation process, and since there is a strong coupling between HESS and power allocation, in this paper an adaptive multi-objective joint optimization framework (AMJOF) for HESS design considering energy management strategy (EMS) is proposed. A multi-objective joint optimization method is introduced into the framework to achieve strong working condition adaptability and reach the most suitable energy management for marine HESS design with the lowest investment cost and minimum battery degradation. In addition, based on adaptive segmentation and frequency control, a novel EMS is proposed, which achieves efficient power allocation, and the evaluation indicator is introduced to quantify the performance of different optimization. The results indicate that the AMJOF can achieve excellent performance and find the optimal solution for operation of the ship.

An Evaluation Method of Ship-Tracking Algorithms for High-Frequency Surface Wave Radar considering High Maneuvers Generated by the MMG Model

Thelong-distance coverage of high-frequency surface wave radar (HFSWR) has promoted it as an enormous means for ship monitoring on the country’s maritime territory. Since it is a primaryradar, noncooperative targets can also be detected. However, this radar also has a shortcoming of low spatial and temporal resolutions due to the narrow available bandwidth in the HF band. This limitation can reduce the performance of ship detection and tracking, especially for highly maneuvering ships. This paper proposes a new method to assess the tracking algorithm for a high-maneuvering ship. The absence of a high-maneuvering plot in the AIS data and existing analytical models are replaced by the MMG model run on MANSIM software. The linear, turning, and zigzag motions are generated and used to evaluate the tracking algorithms. The Monte Carlo simulation was conducted regarding the degradation of spatial resolution in the higher radial range. The tracking performance was analyzed by calculating the RMSE of four parameters, i.e., absolute position, radial range, bearing angle, and speed. For a trial case, four tracking algorithms were evaluated, i.e., Kalman filter (KF), extended Kalman filter (EKF), unscented Kalman filter (UKF), and particle filter (PF). The evaluation results showed that the EKF tracker had a minor error for the linear track with RMSE of absolute position, radial range, bearing angle, and speed being 1.368 km, 0.526 km, 1.550°, and 0.005 m/s, respectively. Otherwise, the UKF performed slightly better than EKF for the high maneuver targets. The RMSE of absolute position, radial range, bearing angle, and speed were 1.649 km, 0.639 km, 1.919°, and 0.165 m/s, respectively. The results also ensure the applicability of the MMG model to evaluate the tracking algorithm’s performance in HFSWR.

Biomembrane‐inspired design of medical micro/nanorobots: From cytomembrane stealth cloaks to cellularized Trojan horses

AbstractMicro/nanorobots are promising for a wide range of biomedical applications (such as targeted tumor, thrombus, and infection therapies in hard‐to‐reach body sites) because of their tiny size and high maneuverability through the actuation of external fields (e.g., magnetic field, light, ultrasound, electric field, and/or heat). However, fully synthetic micro/nanorobots as foreign objects are susceptible to phagocytosis and clearance by diverse phagocytes. To address this issue, researchers have attempted to develop various cytomembrane‐camouflaged micro/nanorobots by two means: (1) direct coating of micro/nanorobots with cytomembranes derived from living cells and (2) the swallowing of micro/nanorobots by living immunocytes via phagocytosis. The camouflaging with cytomembranes or living immunocytes not only protects micro/nanorobots from phagocytosis, but also endows them with new characteristics or functionalities, such as prolonging propulsion in biofluids, targeting diseased areas, or neutralizing bacterial toxins. In this review, we comprehensively summarize the recent advances and developments of cytomembrane‐camouflaged medical micro/nanorobots. We first discuss how cytomembrane coating nanotechnology has been employed to engineer synthetic nanomaterials, and then we review in detail how cytomembrane camouflage tactic can be exploited to functionalize micro/nanorobots. We aim to bridge the gap between cytomembrane‐cloaked micro/nanorobots and nanomaterials and to provide design guidance for developing cytomembrane‐camouflaged micro/nanorobots.

Аналіз робіт з модернізації ЗСЗВ 9К51 «Град» для визначення технічних характеристик перспективного некерованого РС калібру 122 мм

The article dwells on the multiple launch rocket systems with high firepower, firing rate and manoeuvrability, which continue to be one of the basic means of destruction of the land forces in the conditions of the modern armed conflicts. Authors observed the importance of reconstruction and upgrading of multiple launch rocket systems of Grad 9К51, Hurricane 9К57 and Tornado 9К58 types and missiles they use by the enterprises of the domestic military-industrial complex. The article dwells on the main areas of upgrading of the multiple launch rocket system Grad 9K51 performed by NPO Splav and co-operating enterprises in 1997‒1998 for a foreign customer. The key factors that allowed improving the performance of the Grad system in the upgrading process are identified in this article. The main characteristics of the unguided missiles 9M217, 9M218, 9M521, 9M522, designed for the foreign customer, had been investigated. The performance characteristics of the Tornado-G multiple launch rocket system which went into service with the Ministry of Defense of the Russian Federation in 2014, as well as the family of the upgraded unguided missiles 9M538, 9M539, 9M641, are analyzed. The article identifies the main areas of work for further improvement of the performance characteristics of the 122-mm unguided missile, developed by Yuzhnoe Design Office for the multiple launch rocket system 9K51 Grad. This article can be useful for the specialists in development of new and upgrading outdated systems of rocket weapons. Key words: multiple launch rocket system (MLRS), missile, 9K51 Grad, 9M217, 9M218, 9M521, 9M522, Tornado-G, 9M538, 9M539, 9M541.

A Novel and Efficient Authentication Scheme Based on UAV-UAV Environment

Nowadays, unmanned aerial vehicles (UAVs) are used in various fields due to their high maneuverability and low cost of construction and use. With the development of UAV technology, it has become a trend for UAVs to cooperate with each other to complete assigned tasks. Multiple UAVs are combined according to a certain structure, and through the information sharing between them, a cooperative effect is generated to achieve intelligent collaborative task execution. However, information sharing is carried out on a public channel, so ensuring secure communication between UAVs is crucial. Moreover, UAVs are easily captured by an adversary, who can impersonate legitimate UAVs to disrupt communications if UAVs’ internal secrets that are stolen. Therefore, we propose a lightweight authentication scheme based on physical unclonable function (PUF), to provide mutual authentication between UAVs. PUF is embedded in the unmanned aerial vehicle (UAV) to defend against physical capture attack. Furthermore, to evaluate the security and performance of our scheme, formal and informal security analyses and formal security verification of the scheme are performed, and the performance of the scheme is compared with existing UAV schemes. The above analyses show that our scheme has great advantages in terms of security and overheads.

A hybrid thrusting system for increasing the endurance time of multirotor unmanned aerial vehicles

One of the most significant disadvantages of electric multirotor unmanned aerial vehicles is their short flight time compared to fuel-powered unmanned aerial vehicles. This is mainly due to the low energy density of electric batteries. Fuel has much more energy density when compared to batteries. Electric-powered motors in multirotor unmanned aerial vehicles cannot be replaced with fuel-based engines because the stability and control of multirotor unmanned aerial vehicles rely on the high response rates of electric motors. One of the possible solutions to overcome this problem of short endurance times is by using hybrid thrusting systems that combine the advantages of both fuel and electrical propulsion systems, where high maneuverability and long endurance flight time could be achieved. In this work, hybrid thrusting and power systems for multirotor unmanned aerial vehicles are studied. Targeted hybrid thrusting systems consist of combustion engines, electric motors, and their power sources. Then a hybrid thrusting system-based quadrotor unmanned aerial vehicle model is developed. The article presents the altitude and attitude control systems of the developed hybrid thrusting system-based unmanned aerial vehicle. The presented hybrid quadcopter model comprises four electric motors and one fuel engine. The fuel engine used in this work is a 4.07 cc internal combustion engine targeting 2–3 kg unmanned aerial vehicles with up to 5 kg maximum takeoff weight. The developed hybrid quadrotor unmanned aerial vehicle achieved a 139% improvement in flight time when compared with traditional electric-based quadrotor unmanned aerial vehicles. The article also reports on other flight time-related issues such as the optimal fuel mass to battery size ratio to maximize the endurance time of the quadrotor unmanned aerial vehicles.

An underwater explorer remotely operated vehicle: Unraveling the secrets of the ocean

In recent years, underwater robots have been an essential focus of marine science and technology applications. Whether it is the application of military tasks or general civil affairs, underwater robots have played a significant role. For example, unmanned underwater vehicles (UUVs) can work in the sea for a long time, have high maneuverability, and perform various underwater tasks. There are many subcategories of UUVs, such as autonomous underwater vehicles (AUVs), remotely operated vehicles (ROVs), and autonomous and remotely operated vehicles (ARVs) (Kong et al., 2020).

Dynamic CFD/CSD Coupling Research for Flexible Micro Aircraft

Bio-inspired flapping wing aircraft have made progress in recent years. Flying birds can fly in various low Reynolds numbers (103-105) with high flight stability and maneuvering ability by use of the flexible deformation of skeletal muscle structures or thin-film structure wings. Early studies mainly focused on the aerodynamics and kinematics of the flapping wings, with relatively little research on the flexible structure, and the aerodynamic structure coupling characteristics of micro flappings are still unclear. At present, the focus of research is to evaluate the impact of structural deformation on the aerodynamic characteristics of flexible micro-flapping wing. A CFD/CSD coupling solver are developed and several technical challenges related to the CFD/CSD interface are resolved in this study (CFD/CSD data exchange method and moving mesh generation). The aerodynamic characteristics of five flexible wings with different structural parameters are calculated and compared. The results show that structural parameters play an important role in aerodynamic performance, which also indicates that the potential aerodynamic performance can be improved by the optimal structural design.

Joint Optimization of Trajectory and User Association via Reinforcement Learning for UAV-Aided Data Collection in Wireless Networks

Unmanned Aerial Vehicles (UAVs) can be used as aerial base stations for data collection in next-generation wireless networks due to their high adaptability and maneuverability. This paper investigates the scenario where multiple UAVs cooperatively fly over heterogeneous ground users (GUs) and collect data without a central controller. With the consideration of signal-to-interference-and-noise ratio (SINR) and fairness among users, we jointly optimize the trajectories of UAVs and the GUs associations to maximize the total throughput and energy efficiency. We formulate the long-term optimization problem as a decentralized partially observed Markov decision processes (DEC-POMDP) and derive an approach combining the coalition formation game (CFG) and multi-agent deep reinforcement learning (MADRL). We first formulate the discrete association scheduling problem as a non-cooperative theoretical game and use the CFG algorithm to achieve a decentralized scheme converging to Nash equilibrium (NE). Then, a MARL-based technique is developed to optimize the trajectories and energy consumption continuously in a centralized-training but decentralized-execution manner. Simulation results demonstrate that the proposed algorithm outperforms the commonly used schemes in the literature, regarding the fair throughput and energy consumption in a distributed manner.

Enhanced performance of hysteresis controlled single phase Ac/Dc buck converter system using cubic boron arsenide semiconductor material

This paper presents a single phase AC-DC buck converter using Hysteresis controller in order to provide superior response. As an alternative to the DC grid, the single phase AC/DC buck converter is getting prominence. The rectifier's AC output is fed into a Buck converter (BC) and then filtered with a filter. Higher order harmonic components are present in the power drawn by nonlinearandunbalancedloads,whichinturn raises the supply current’s totalharmonicdistortionlevel. In comparison to other controllers, hysteresis current controllers are well known for their robustness, faster error tracking, greater dynamic response and simplicity of implementation. In this study, a single phase buck converter system with a Proportional Integral controller (PIC) and a Hysteresis controller is modelled and simulated (HC). The findings of comparing the performance of buck converters with PIC and HC are presented. The outcomes show that an HC controlled Buck Converter responds more quickly. Because of improvements in material science and a desire for higher performance, wide band-gap semiconductors are used in switching circuits. This paper also discusses the cubic boron arsenide semiconductor material, which is used to create the power electronic switches used in AC-DC converters and has good thermal conductivity and high manoeuvrability for electrons and holes.

SISTEM DE ACȚIONARE ELECTRICĂ PENTRU ECHIPAMENT DE RECOLTAT BIOMASA ACVATICA, ALIMENTAT DIN BATERII Li-ION

The development of an electric vehicle harvester for aquatic vegetation is a technical challenge for researchers due to specific requirements: high-torque operation at low travel speeds, high maneuverability, high load capacity, low draught, and affordable price. The collective of authors proposed an electro-hydraulic architecture based on paddles driven by hydraulic motors for propulsion and auxiliary services also driven by motors and hydraulic actuators. The proposed energy source for the aquatic harvester is electric batteries, it was developed a system of 33 kWh Li-Ion batteries connected in parallel, which power an electronic converter and a 14.5 kW rated power electric motor that drives a hydraulic double-circuit pump. The vehicle can be controlled remotely. The paper presents the prototype made and the results obtained during laboratory tests performed for the electric powering system.