Vehicle Heading Research Articles

Dynamic event-triggered prescribed performance disturbance rejection fault-tolerant trajectory tracking for surface vehicles

In this article, a dynamic event-triggered prescribed performance disturbance rejection fault-tolerant scheme is designed for the trajectory tracking of surface vehicles. The external time-varying disturbances and loss-of-effectiveness thruster faults are addressed separately. By constructing the separate observers, the external time-varying disturbances and the loss-of-effectiveness thruster faults are on-line estimated, respectively. The prescribed performance and error transformation functions enable the transient and steady-state performance to settle within pre-specified function values. The dynamic event-triggering is introduced so that commanded control signals are temporarily kept under predefined conditions to reduce wear and tear on the thrusters especially in harsh environmental condition. With the aid of the vectorial backstepping technique, the finial control law is derived such that the position and heading of vehicles can be forced to track the reference trajectories in disturbance and fault conditions. Application example on a 1:70 scaled model vessel in the different cases clarify the scheme.

Effect of ESC (electronic stability control) on tree and pole impacts with focus on rear impacts

ObjectiveThe effect of ESC (Electronic Stability Control) was investigated for the rate of crash exposure, serious injury and fatality in pole and tree impacts. Field data was analyzed by crash type (front, side, rear and rollover) and model year (MY) before, during and after the implementation of ESC. MethodsThe number of pole and tree impacts was determined for four groups of vehicle model years (MY): 1981–1989 MY and 1990–2002 MY before the introduction of ESC, 2003–2009 during the phase-in of ESC and 2010–2020 MY after essentially all vehicles were equipped with ESC. Collisions were grouped by front, side, rear and rollover. Three databases were analyzed: 1990–2020 FARS, 1990–2015 NASS-CDS and 2017–2020 CISS. Vehicle registration was obtained from IHS Markit to determine the rate of pole and tree impacts per 100,000 registered vehicles. The same vehicle selection criteria was used for vehicle registration and crash data. ResultsFatalities dropped 65.2 % (95 % CI, 63.0–67.4 %), z = 43.7, p < 0.001 into poles and 60.3 % (95 % CI, 59.0–61.5 %), z = 72.4, p < 0.001 into trees in vehicles equipped with ESC comparing 1990–2002 MY to 2010–2020 MY vehicles. Seriously injured occupants in crashes with poles dropped 75.9 % (95 % CI, 75.0–76.9 %), z = 116, p < 0.001 between 1990 and 2002 MY and 2010–2020 MY vehicles. There was a 65.2 % (95 % CI, 64.4–65.9 %), z = 141, p < 0.001 reduction in tree impacts. The crash exposure to pole impacts dropped 36.0 % (95 % CI, 35.8–36.3 %), z = 252, p < 0.001 from 80.77/100,000 registered vehicles in 1990–2002 MY vehicles to 51.69/100,000 in 2010–2020 MY vehicles. There was a 61.0 % (95 % CI, 60.8–61.2 %), z = 434, p < 0.001 reduction in tree impacts. For rear impacts, fatalities dropped 82.9 % (95 % CI, 71.3–94.4 %), z = 9.37, p < 0.001 into poles and 74.8 % (95 % CI, 67.8–81.9 %), z = 14.8, p < 0.001 into trees. Serious-injury in rear impacts with poles and trees were essentially eliminated in 2010–2020 MY vehicle crashes. There were significant drops in fatalities in side and frontals impacts and rollovers in vehicles equipped with ESC. ConclusionESC helps the driver maintain vehicle heading and significantly reduced the rate of serious injury and fatality in off-road impacts with poles and trees. The benefits of ESC may not be realized with impairments when the driver does not appropriately steer the vehicle.

Применение оксидных покрытий, полученных экстракционно-пиролитическим методом, в космической технике

The problem of creating antimicrobial protection methods in rocket and space technology requires new approaches, in particular, the development of antibacterial coatings to protect the payload of launch vehicles. Also, in outer space outside the Earth's atmosphere, ultraviolet radiation with a wavelength of less than 280 nm (hard and vacuum ultraviolet) accelerates degradation of materials. It is relevant to create protective coatings for various materials used in space. An innovative extraction-pyrolytic method for producing oxide films containing copper, titanium and titanium oxide nanoparticles is considered. As a result, the compositions of effective antibacterial coatings with the function of protection against UV radiation have been established. The intended service and design features of the part on which the coating is applied are considered, and a flow diagram for applying an antibacterial coating to protect the internal volume of the fairing from bacteria circulating in the head of the launch vehicle is proposed. The possibilities of protection against UV radiation by applying oxide films to the outer surface of devices and rocket parts have been studied.

Vehicle Heading Enhancement Based on Adaptive Sliding Window Factor Graph Optimization for Gyroscope/Magnetometer

Vehicle Heading Enhancement Based on Adaptive Sliding Window Factor Graph Optimization for Gyroscope/Magnetometer

Enhanced Vehicle Heading Estimation for Magnetometer/Gyroscope Integration With Random Magnetic Interference Detection Based on Pearson Correlation Coefficient

Enhanced Vehicle Heading Estimation for Magnetometer/Gyroscope Integration With Random Magnetic Interference Detection Based on Pearson Correlation Coefficient

Application of Acoustic-solid Coupling Theory in New Energy Vehicle Noise Control

The development of new energy vehicles has attracted much attention due to the strong promotion and popularisation of the concept of low carbon and environmental protection, and the increasing demand for environmental protection in cars. Although these vehicles meet people’s requirements for resource and environmental protection, the noise generated during the driving process affects the comfort of the vehicle occupants and the concentration of the vehicle driver. To address this problem, the research proposes to improve the noise control technology of new energy vehicles based on acoustic-solid coupling theory and to test the practical application effect of this technology. The test results show that the maximum acceleration of vibration at the roof, floor, axle head, and spring of the new energy vehicle are 1.48 m/s2, 1.02 m/s2, 0.079 m/s2, and 0.020 m/s2 respectively, which are lower than the maximum acceleration before the use of this technology. The maximum sound pressure at the windscreen and side window glass of the new energy vehicle is 80 dB(A) and 73 dB(A) after the use of this technology. The maximum sound pressure at the driver’s ear was 62 dB(A) and 77 dB(A) when the vehicle was driven on different road surfaces, which were lower than the sound pressure values before use. In summary, the research proposes to improve the noise control technology of new energy vehicles based on the sound-solid coupling theory, which can have the effect of reducing the noise value generated by new energy vehicles and improving the comfort of users.

A survey of fire accidents during the process of highway tunnel operation in China from 2010 to 2021: Characteristics and countermeasures

China has the largest number of highway tunnels in the world and the most rapid development in this scope. Along with the advancement of highway tunnels, fire incidents continue increasing, causing significant damages to life and property safety. The knowledge of characteristics of highway tunnel fire accidents is essential for the fire authorities to update their safety policies on tunnels and also useful for the scholars to carry out basic and applicable researches. Previous studies have been performed on fire accident statistics in highway tunnels before 2016. The dataset after 2016 are unknown. To solve this problem, the present study examined total 256 fire incidents in Chinese highway tunnels during 2010–2021 based on police-reported database. The results showed that the fire number in 2017–2021 is almost three times that in 2010–2016. The fires occur more in spring and summer. The majority of fires occur in the long and extra-long tunnels (80%), in the one-way tunnels (90%), in the curved tunnels (70%), in the interior zone of tunnels (67.2%) and in the low altitude areas (60%). The top two burning vehicle types are heavy goods vehicles (HGVs, 38.1%) and passenger cars (37.2%). A total of 81.2% of fatalities in highway tunnel fires are associated with HGVs. The head of vehicle (41.8%), tire (25.3%) and goods (15.3%) are the top three causes of fire. Despite the fact that 92.7% of cases are single fire category while spread fire category only accounts for 7.3%, the spread fire has a more than 7 times higher casualty rate than the single fire. Based on the results, some useful fire safety measures for highway tunnels are proposed. It is hoped that this work could provide some data supports and references for tunnel fire safety and relative policy-making.

Where am I heading? A robust approach for orientation estimation of autonomous agricultural robots

Reliable knowledge of the vehicle heading plays a significant role in the autonomous navigation of agricultural Unmanned Ground Vehicles (UGVs), especially in the context of unstructured outdoor environments such as rural and forestry scenarios. However, achieving this information with an acceptable degree of confidence is a non-trivial task and still an open field of research. Expensive solutions are available on the market, but they often discourage most farmers due to the large investments needed for the startup. This paper introduces a novel algorithmic solution for reliable evaluation of the absolute vehicle heading, grounded on adaptive Kalman filtering with input evaluation via linear regression analysis. The proposed approach provides a functional and affordable solution to the heading estimation problem that can be used in real-world applications. The system is validated through an extensive experimental campaign using an all-terrain tracked rover operating in agricultural settings, showing good accuracy compared to other approaches, such as a dual GPS method found in the literature.

Location-Guided LiDAR-Based Panoptic Segmentation for Autonomous Driving

The application of artificial intelligence in autonomous driving is becoming increasingly extensive. LiDAR-based 3D point cloud panoptic segmentation is one of the most promising and arduous tasks. Although recent methods have produced promising results, most of them ignore the prior distribution of objects in the 3D point clouds. In this paper, we first investigate the distribution of objects around the heading of vehicles and observe that several objects are severely biased. On the basis of this observation, we use the bird&#x0027;s eye view (BEV) representation to project the 3D point clouds into a 2D image and divide the BEV projection into eight areas. For each area, we apply input-dependent convolution kernels to extract the local feature. These local features are concatenated to the panoptic backbone for panoptic segmentation. We validate our method on the validation and test sets of the SemanticKITTI dataset. The proposed method outperforms all state-of-the-art methods based on 2D projection in terms of higher panoptic quality scores.

RESULTS OF SEMI-NATURAL TESTS OF THE AUTONOMOUS DETERMINATION OF THE VEHICLE LONGITUDE AND LATITUDE

Navigation parameters such as vehicle heading, linear speed and latitude and longitude are determined today, as a rule,using satellite navigation systems. However, there is a need for autonomous determination of navigation parameterswhen satellite navigation system signals are unavailable for one reason or another. For example, satellite navigationsystem signals can be jammed by electromagnetic countermeasures.Autonomous systems for determining the vehicle navigation parameters are inertial navigation systems, the basis ofwhich is the double integration of signals from accelerometers, as well as the integration of signals from gyroscopes toform one or another coordinate system, if we are talking about strapdown inertial navigation systems (SINS).Integration of the output signals of accelerometers and gyroscopes, which contain errors, leads to the accumulation ofSINS errors. To increase accuracy, SINS are integrated, for example, with satellite navigation systems. However, suchsystems cease to be completely autonomous.The article uses the method of autonomous determination of vehicle latitude and longitude, which is a new method ininertial navigation. The method is based on the strapdown inertial technology, which, unlike the standard methods usedin SINS, does not use the integration of the output signals of accelerometers and gyroscopes. To determine the angles oflatitude and longitude, the signals of the gyroscopes included in the inertial measurement unite (IMU) are used.As a result of a semi-natural experiment, the efficiency of the method of autonomous determination of latitude andlongitude was verified. Flight data of a small-sized aircraft were used for experimental verification. The data containedinformation about the angles of the heading, pitch, roll of the aircraft, the output signals of three micromechanicalgyroscopes, three micromechanical accelerometers, information about latitude, longitude and altitude measured by thereceiver of the satellite navigation system, as well as information about the horizontal and vertical components of speedand current time. Plots of calculated values of latitude and longitude and values measured using the receiver of thesatellite navigation system are given. From the given plots and tables, it can be seen that from a certain time, thecalculated values coincide with the "reference" ones, which confirms the efficiency of the method of autonomousdetermination of latitude and longitude.

State-dependent finite-time controller design and its application to positioning control task for underactuated unmanned surface vehicles

In this study, an accurate state-depended finite-time positioning control framework is proposed for underactuated unmanned surface vehicles (USVs). Three control objectives have been developed to guide the surge, sway, and yaw motions, where the surge and yaw motions are directly controlled by the USV propulsion system. Due to the USV’s underactuated actuator configuration, the sway motion is indirectly affected by the input of sway disturbance force whose magnitude and direction have sustained variations via the adaption of vehicle heading. To handle the problems associated with heading assignment, time-varying external disturbances, as well as modeling and parameter uncertainties, a state-dependent finite-time controller has been proposed to realize these control objectives. The proposed controller is composed of two parts, namely an online state-constrained polynomial planning and an uncertainty-estimated control execution. The function of this state-constrained polynomial planning is to satisfy all the system state constraints and generate the planning acceleration for the control law execution. Relying on an accurate estimation of unknown uncertainties, the control law is executed at high frequency and established as an algebraic formulation. The system convergence controlled by the proposed scheme is then analyzed. Simulated studies and experimental validations were carried out to verify the proposed controller for the positioning control task from the perspective of effectiveness and robustness.

WITHDRAWN: 3 Axis Gyro Accelerometer & Artificial Intelligence based Enhancement of GPS Accuracy

The accuracy of positioning is a problem for location-based applications when using a cheap GPS receiver (GPS). This research, however, provides an alternative literature review on the topic of how to enhance the positioning precision of inexpensive GPS receivers used in real-time navigation. Scientists have developed a method for precisely estimating a vehicle's location based on GPS coordinates (latitude, longitude, time, and velocity) by combining information about the vehicle's heading, its current speed, and the distance between two waypoints. Coordinate translation, as well as checks for invalid data, and utilization of the previously estimated valuable reference point, all contribute to an increase in precision. As such, a GPS simulation can be used to assess the reliability of GPS velocity readings. Thanks to GPS, the researcher can track the driver's location, speed, and acceleration in real time. A driver's propensity for taking chances can be uncovered in a GIS setting. Second, researchers can get high-resolution data on vehicle activity just before an accident, which makes it easier to estimate speeds with less error and bias. In this paper, we present a double-antenna method for improving GPS precision by utilizing both an active antenna and a ground plane antenna. The author has proposed improvement in GPS Receiver Accuracy Using Antenna Optimization Techniques like Ground Plane Enhancement for SNR Improvement along with Sensor Fusion combined with Artificial Intelligence. Sensor Fusion Primarily comprises of 3-Axis Accelerometer With 3-Axis Gyroscope forming an IMU, which along with AI, is used to predict navigation parameters in absence of GPS Signal, and when GPS drop communication with satellite due to any cause, Once GPS signal is lost with any cause then this change in delta latitude and delta longitude will compute by our trained artificial neural network, then according to this interpolation, artificial neural network calculates latitude and longitude.

Numerical Simulation of the Maneuvering Motion Wake of an Underwater Vehicle in Stratified Fluid

When a vehicle moves underwater, disturbance is generated and a wake remains that destroys the original free surface and produces a new wake. In order to study the mechanism and characteristics of the wave-making wake generated by the maneuvering motion of an underwater vehicle in density-stratified fluid, the k-ε model and the VOF method that is based on the RANS equation were used in this paper to analyze the SUBOFF model in stratified fluid at different drift angles. Numerical simulation of the maneuvering motion was carried out under these angles, and the corresponding changes in flow field caused by this motion were analyzed. The results from the comparison and analysis of the surface wave wakes under different drift angles in stratified fluid show that with the increasing drift angle, the motion wake of the vehicle still exhibits obvious Kelvin wave system characteristics. However, there are significant changes in hydrodynamic performance. The asymmetry of the surrounding flow field will increase with the increase in the drift angle. The pressure of the underwater vehicle is inversely proportional to the velocity of the surrounding flow field, and the amplitude of the peak and trough of the free surface wave is linearly related to the change in the drift angle. The numerical simulation can serve as a reference for the non-acoustic detection of the motion heading of an underwater vehicle and the motion trajectory of anti-reconnaissance underwater vehicles under actual sea conditions.

IMPLEMENTASI KURIKULUM RELAKSASI DALAM PEMBELAJARAN MASA PANDEMI COVID-19 KOMPETENSI KEAHLIAN TKRO DI SMK N 2 YOGYAKARTA

AbstractThe study aims to describe the implementation of a relaxing curriculum during the covid-19 in the competence expertise learning process at 10th grade techinical automotive Yogyakarta’s Vocational High School (SMK N 2 Yogyakarta) which included the formulating aspects of the relaxation curriculum, stake holder’s involvement, management performance’s of the learning process, obstacles during the implementation of the relaxation curriculum and follow-up of the learning curriculum used. This is a kind of descriptive research. The research subject is teachers, students of the competition for 10th-grade technical automotive engineering, and several of stakes holder (head of technical automotive light vehicle, school committee, industry, parents of students, school supervisor and covid-19 cluster head) who have a direct interest in the implementation of learning at SMK N 2 Yogyakarta. Data of this research was collected by questionnaires, interviews, documentation, and observation. Data was analyzed by descriptive statistics. The data of the research were analyzed by using descriptive statistical techniques that focused on the central tendency of the data. Studies indicate that the general conclusion of the implementation on the relaxation curriculum to studies held by SMKN 2 Yogyakarta was carried out in good. Keyword: implementation of relaxing curriculum, planning, management implementation, evaluation and follow-up about curriculum which used.

Relative Timing of Off‐Axis Volcanism From Sediment Thickness Estimates on the 8°20’N Seamount Chain, East Pacific Rise

AbstractVolcanic seamount chains on the flanks of mid‐ocean ridges record variability in magmatic processes associated with mantle melting over several millions of years. However, the relative timing of magmatism on individual seamounts along a chain can be difficult to estimate without in situ sampling and is further hampered by Ar40/Ar39 dating limitations. The 8°20’N seamount chain extends ∼170 km west from the fast‐spreading East Pacific Rise (EPR), north of and parallel to the western Siqueiros fracture zone. Here, we use multibeam bathymetric data to investigate relationships between abyssal hill formation and seamount volcanism, transform fault slip, and tectonic rotation. Near‐bottom compressed high‐intensity radiated pulse, bathymetric, and sidescan sonar data collected with the autonomous underwater vehicle Sentry are used to test the hypothesis that seamount volcanism is age‐progressive along the seamount chain. Although sediment on seamount flanks is likely to be reworked by gravitational mass‐wasting and current activity, bathymetric relief and Sentry vehicle heading analysis suggest that sedimentary accumulations on seamount summits are likely to be relatively pristine. Sediment thickness on the seamounts' summits does not increase linearly with nominal crustal age, as would be predicted if seamounts were constructed proximal to the EPR axis and then aged as the lithosphere cooled and subsided away from the ridge. The thickest sediments are found at the center of the chain, implying the most ancient volcanism there, rather than on seamounts furthest from the EPR. The nonlinear sediment thickness along the 8°20’N seamounts suggests that volcanism can persist off‐axis for several million years.

Characteristic analysis and blind area prediction of aeromagnetic scalar gradient detection method

To analyze the characteristics of the aeromagnetic scalar gradient detection method, a uniformly magnetized ellipsoid is used to simulate an unexploded ordnance, and a magnetic field detection model is established in the International Geomagnetic Reference Field based on rotation matrices. Furthermore, the spatial distribution of the target’s magnetic field is simulated. The results indicate that the scalar gradient detection curve is closely related to the unmanned aerial vehicle (UAV) heading, geomagnetic direction, and target attitude. According to the measured data, the aeromagnetic detection system exhibits differences in the detection of different headings, indicating that some “blind areas” exist in the scalar gradient magnetic detection method. The experimental measurement by a quadrotor UAV equipped with two optical pump magnetometers verifies that the scalar gradient detection method can effectively eliminate the geomagnetic field as well as the interferences of the UAV itself. Furthermore, the angular relationship between the target magnetic field contour distribution and the heading is found to be the main reason that the scalar gradient detection system enters the “blind detection area.” Therefore, a flight strategy of “positive direction + orthogonal grid” is proposed. This method effectively reduces the missed detection rate of scalar gradient detection and provides strategic guidance for the detection path of aeromagnetic scalar gradient system.

Low-Frequency Trajectory Map Matching Method Based on Vehicle Heading Segmentation

Numerous Global Positioning System connected vehicles are collecting extensive data remotely in cities, enabling data-driven infrastructure planning. To truly benefit from this emerging technology, it is important to combine telematics and map data to make it easier to extract and mine useful information from the data. By performing map matching, data points that cannot be accurately located on the road network can be projected onto the correct road segment. As an important means of remote data processing, it has become an important pre-processing step in the field of data mining. However, due to the various errors of location devices and the complexity of road networks, map matching technology also faces great challenges. In order to improve the efficiency and accuracy of the map matching algorithm, this study proposes an offline method for low-frequency trajectory data map matching based on vehicle trajectory segmentation. First, the trajectory is segmented based on the vehicle’s travel direction. Then, the comprehensive probability of the corresponding road segment is calculated based on the spatial probability and the directional probability of each road segment around the location. Third, the k candidate matching paths under consideration are selected based on the comprehensive probability evaluation. Finally, the shortest path planning and the probability calculation of the different candidate paths are combined to find the optimal matching path. The experimental results on the real trajectory dataset in Shanghai and the road network environment show that the proposed algorithm has better accuracy, efficiency, and robustness than other algorithms.

Uninterrupted path planning system for Multi-USV sampling mission in a cluttered ocean environment

This paper presents an uninterrupted collision-free path planning system that facilitates the operational performance of multiple unmanned surface vehicles (USVs) in an ocean sampling mission. The proposed uninterrupted path planning system is developed based on the integration of a novel B-Spline data frame and particle swarm optimization (PSO)-based solver engine. The new B-spline data framing structure provides smart sampling of the candidate spots without needing full stop for completing the sampling tasks. This enables the USVs to encircle the area smoothly while simultaneously correcting the heading angle toward the next spot and preventing sharp changes in the vehicle's heading. Then, the optimization engine generates optimal, smooth, and constraint-aware path curves for multiple USVs to conduct the sampling mission from start point to the rendezvous point. The path generated incorporates controllability over the vehicles' velocity profile to prevent experiencing zero velocity and frequent stop/start switching of the controller. To achieve faster convergence of the optimization routine, a suitable search space decomposition scheme is proposed. Extensive simulation studies emulating a realistic ocean sampling mission are conducted to examine the feasibility and effectiveness of the proposed path planning system. This encapsulates modelling a realistic maritime environment of Indonesian Archipelago in Banda Sea including ocean waves, obstacles, and no-fly zones and introducing several performance indices to benchmark the path planning system performance. This process is accompanied by a comparative study of the proposed path planning system with a well-known state-of-the art piecewise, rapidly exploring random tree (RRT), and differential evolution-based path planning algorithms. The results of the simulation confirm the suitability and robustness of the proposed path planning system for the uninterrupted ocean sampling missions.

Effect of gas blowing on the head of thermal ablation vehicle

The reentry vehicle will encounter thermal ablation, especially at the stagnation point regime. A theoretical work has been done to analyze the thermal effect of gas blowing due to thermal ablation of surface material on the head of a general hypersonic vehicle. By deriving the formulation, research takes into account the effect of gas blowing on the thermal dynamics balance, and then solves them by numerical discretization. It is found that gas blowing will increase the temperature and heat flux at the surface of stagnation point regime.

Nonlinear station keeping control for underactuated unmanned surface vehicles to resist environmental disturbances

This paper presents a station keeping control method for underactuated unmanned surface vehicles (USVs) to resist environmental disturbances with unknown magnitude and direction. Three control objectives are developed, where two of them are for the surge and yaw motions directly controlled by actuators and the last one is for the sway-offset motion affected by sway environmental disturbance acting on the vehicle body. The nonlinear separation principle is introduced and adopted to stabilize the surge, sway, and yaw cascaded systems. To clearly demonstrate the sway-offset impact induced by environmental disturbances, the sway-offset dynamic model affected by sway environmental force is subsequently derived. Finally, a slowly varying adaptive law is proposed to gently alter vehicle heading for the sake of positioning error minimization, and detailed benchmarks are presented to quantitatively determine the gain setting for this adaptive law. When the preset position is well kept, the stable vehicle heading will point against the mean direction of external disturbances such that the yaw control moment is minimized and onboard energy can be saved. Instead of being validated only through simulations, experiments are conducted under real offshore marine conditions to verify the validity and effectiveness of the proposed station keeping method.