Car Motion Research Articles

Detection of Moving Objects in Earth Observation Satellite Images

Moving objects have characteristic signatures in multi-spectral images made by Earth observation satellites that use push broom scanning. While the general concept is applicable to all satellites of this type, each satellite design has its own unique imaging system and requires unique methods to analyze the characteristic signatures. We assess the feasibility of detecting moving objects and measuring their velocities in one particular archive of satellite images made by Planet Labs Corporation with their constellation of SuperDove satellites. Planet Labs data presents a particular challenge in that the images in the archive are mosaics of individual exposures and therefore do not have unique time stamps. We explain how the timing information can be restored indirectly. Our results indicate that the movement of common transportation vehicles, airplanes, cars, and boats, can be detected and measured.

A first analysis of possible elementary causes of self‐excited vibrations in roller coaster rides

AbstractThe emergence of vibrations during a roller coaster ride is a recurring phenomenon that can deteriorate the overall experience and accelerate material fatigue. Nevertheless, the causes of such vibrations are still not completely understood and are consequently not fully predictable during the design process. One possible source lies on the irregularities of the rails, acting as a forced external excitation. However, a spectral analysis shows deviations with respect to real measurements [1], as the frequencies are not synchronous with the car velocity divided by the spatial irregularity period. Therefore, there is an indication that the vibrations may be due to self‐excitation and/or that the developed models should consider other phenomena not yet contemplated. This investigation analyses –for the first time to the knowledge of the authors– the plausibility of various causes of self‐excited vibrations during a roller coaster car motion. Given the complex structure of a real roller coaster train and the intricate geometry of the track, the study considers as a first step minimal dynamical models running along a straight track. The cause analyzed in this paper is the contribution of the transversal friction force component that develops in the wheel‐rail contact interface to the destabilization of the longitudinal motion, as well as the effect of the various geometrical and inertial parameters. In this first analysis, no external excitation is considered. For a range of parameters, the minimal system presents a Hopf bifurcation. The results are plausible from the general behavior and thus this cause may be retained as a candidate for the real vibrations occurring in roller coasters. However, the applicability of these preliminary results to general roller coaster motions is not yet confirmed, but a superposition with other causalities may render effective. In further investigations, a complete train motion on curved tracks and external perturbations will be studied to determine the share of the different causes.

Load of a semi-car having the dismountable roof of composites

Purpose. Creation and substantiation of the measures for adopting the supporting structure of the multipurpose semi-car to carry cargoes that need weather protection. Methodology. For the adaptation of supporting constructions of semi-cars to carriage of cargoes that need weather protection, it was proposed to apply a removable roof manufactured from composites. As the application of a removable roof enlarges the volume of the container of the semi-car, the authors defined the load on its construction with the help of mathematical modeling. The authors see semi-car as a system which includes three components – a supporting construction having a roof with two carts. The Runge-Kutta method was used to calculate the main dynamic parameters of the semi-car. These defined dynamic parameters were accounted during calculation of the strength of the dismountable roof. Graphic spatial modeling of a semi-car with a dismountable roof was performed in the SolidWorks software kit. The calculation of solidity is implemented by the method of ultimate elements using the SolidWorks Simulation program kit. The original frequencies and forms of vibrations of the supporting construction of the semi-car are performed in this research. Findings. The outcomes of a mathematical model of the dynamic loading of the supporting construction of the semi-car having a dismountable roof set that the obtained dynamic parameters are not higher than the allowable values. The acceleration of the semi-car supporting construction in the gravity center made approximately 4.5 m/s2. The vertical dynamic ratio amounts to 0.53. The car motion is evaluated as “excellent”. It was found that when the vertical load acts on the dismountable roof, the maximum tension emerging inside is 173.2 MPa. When concentrated load affects the dismountable roof, the biggest tensions are focused on the zones of its attachment to the upper strapping of the casing, and makes 205.7 MPa. It can be seen from the modal analysis that the first original frequency of the semi-car casing is equal to 9.6 Hz, which is more than the allowable value – 8 Hz. Originality. Models for determining the loading of the supporting construction of the semi-car having a dismountable roof from composites within the general modes of loading operation are given in this study. Practical value. The study results allow expanding the applicability of semi-cars by adapting them to the carriage of cargoes, which need protection from weather effects and can increase the performance of railroad carriage.

Methodology for Maintaining the Dynamic Characteristics of Passenger Cars

The work presents the results of a statistical analysis of random processes of the coefficient of vertical dynamics of a passenger car variation. To determine the dynamic performance of cars the tests were running on the tracks of JSC "Ukrzaliznytsia". The main statistical characteristics of random processes are determined for various modes of car movement along curved and straight sections of the track. As a result of statistical processing of experimental data, correlation functions have been constructed that characterize the degree of connection between different time sections of the process of changing the coefficient of vertical dynamics. The obtained indicators of the law of distribution of the vertical dynamics coefficient values, approximating the models of correlation functions and the numerical values of their parameters, make it possible to further simulate the process of loading a passenger car without carrying out lengthy expensive tests.

A Proposed Controller for an Autonomous Vehicles Embedded System

Many research have observable development in the automated vehicle driving field during the last few decades. This research proposed a simple optimum Intelligent PID (SO PID) controller to simplify the automated vehicle motion control. Control of an autonomous vehicle’s steering routines plays an essential key role. Several steering control procedures are proposed that improve automated vehicle performance. The design of secure embedded control systems must overcome the difficulties associated with designing both computing and control systems. Also, this research introduces a model of the autonomous car prototype controlled via an Arduino microcontroller board and the GPS Module to receive the car coordinates. The car moves safely, and autonomously consequently avoiding the risk of human faults. Several algorithms such as angle and distance calculations to the waypoint and obstacle detection are combined to control the car movement.

Analysis of energy efficiency and dynamics during car acceleration

In this work, the authors focused on analyzing the energy efficiency and dynamics during car acceleration, featuring investigation of acceleration dynamics under various acceleration intensities. The tests were performed in the speed range between 45 km/h and 120 km/h, at a constant gear ratio. This enabled obtaining variable dynamic parameters of the acceleration process, ranging from about 0.1 to 1.4 m/s2 , and recording variation in fuel consumption from 6.28 to 27.03 dm3 /100km. The study focused on determining the relation between fuel consumption, energy efficiency and vehicle acceleration depending on the available drivetrain power. The relation between fuel consumption and vehicle acceleration was described by using the dynamic index. The proposed dynamic index takes into account the energy (from burned fuel) and vehicle acceleration intensity to obtain an objective metric for characterizing the acceleration process. The aforementioned index takes the form of the passenger car movement energy quality index and can be related to widely known physical properties, thus ensuring its universality. The index expresses the energy expenditure within the time needed to accelerate a vehicle weighing 1kg by a 1m distance. As opposed to other criteria that are applied to the assessment of passenger cars dynamics, the index shows a high determination coefficient R2 in excess of 0.99, and can be used as a universal metric to test other vehicle types.

The Failure Analysis of Unintended Elevator Car Movement Protection

The unintended movement protection device of elevator car can prevent the accident of passenger shearing and extrusion caused by the fracture of elevator traction wheel shaft and the failure of control system components. However, due to the relatively complex composition of this device, many car accidental movement protection devices in the actual use process do not meet the requirements of standards and specifications. In view of the problems found in the inspection, several typical failure cases are summarized, and the reasons for the failure of these devices are analyzed. At the same time, the corresponding solutions under the current technical conditions are put forward, which provides a reference for the development of field inspection and the revision of specifications and standards.

Hand Gesture-Controlled Robotic Arm with All-Terrain Surveillance Car

Abstract: In this proposed work, a gesture-based all-terrain car and a gesture-based robotic arm are designed to perform various real-life tasks. The motion of the robotic arm is based on the gesture input provided by the user. The use of a gesture controller provides ease for the user to control it efficiently. To have a clear and proper vision around the car, First-person View (FPV) cameras have been brought into the picture with a featured mechanism of pan and tilt placed in a particular position per the user's requirement and operation. A setup of two FPV cameras placed side by side can be made so as to have a panoramic view of the front of the car. Basic hand gestures are required for the motion of the surveillance car. A conveyor belt and off-road sturdy tires can be used for the purpose of all-terrain. The user can also get a virtual view of the robot by using a Virtual Reality (VR) set.

Navigation Data Exchange for Traffic Control

An increase in the number of cars is higher than rates of transport infrastructure development, resulting in a reduction of cargo and passenger transportation efficiency in city conditions. Simulation of flow irregularity in time (peak hour) shows the key role of a car motion interval as a factor of overcoming accumulation at average speed reduction in conditions of highly loaded roads. To reduce the effective time of driver reaction, defining the least distance between cars, it is necessary to minimize the influence of human factors. Automation of the process (unmanned control) requires an effective exchange of navigation and route data between traffic participants. A summary of requirements for such an information exchange system defines the priority of the suggested communication and navigation system (CNS) on the base of radio broadcast communication. Its application gives an opportunity to rise simultaneously traffic safety and efficiency. An increase in neighbor driver action predictability leads to traffic safety ensuring. The exchange of data with traffic control centers (TCC) enables the centralization of motion regulation. A distributed network of transceiver stations forms a local positioning system based on trilateration principles. Algorithms of onboard positioning result verification and automatic resolution of communication conflicts ensure high reliability of CNS functioning. Refusal from point-to-point communication principles allows it to operate even in conditions of high car density up to several thousand per square kilometer. In cooperation with advanced technologies of traffic organization (formation of city highway grid and “total green wave” mode), CNS and TCC are capable of rising the average speed in city conditions higher than 45 km/hour. The aggregate economy of expense on last mile transportation because of the suggested innovations is to be at the level of several GDP percent due to a decrease in accidents and congestion even without accounting for social and ecological effects.

A New Self-Tuning Nonlinear Model Predictive Controller for Autonomous Vehicles

Autonomous driving has recently been in considerable progress, and many algorithms have been suggested to control the motions of driverless cars. The model predictive controller (MPC) is one of the efficient approaches by which the speed and direction of the near future of an automobile could be predicted and controlled. Even though the MPC is of enormous benefit, the performance (minimum tracking error) of such a controller strictly depends on the appropriate tuning of its parameters. This paper applies the particle swarm optimization (PSO) algorithm to find the global minimum tracking error by tuning the controller’s parameters and ultimately calculating the front steering angle and directed motor force to the wheels of an autonomous vehicle (AV). This article consists of acquiring vehicle dynamics, extended model predictive control, and optimization paradigm. The proposed approach is compared with previous research in the literature and simulation results show higher performance, and also it is less computationally expensive. The simulation results show that the proposed method with only three adjustable parameters has an overshoot of about 8% and its RMSE is 0.72.

NOISE PROTECTION PRINCIPLES OF HIGHWAY CONSTRUCTION

According to the results of scientific research, it was established that the noise generated by vehicles has a negative impact on people's health, therefore, effective solutions in the field of construction and planning are needed to reduce the noise load on residential areas. Usually, noise is produced by the movement of cars, their engines and road surfaces. Noise can have a negative impact on people's health, leading to stress, sleep problems, impaired concentration and other physical and psychological health problems. The most important noise protection principles are the selection of a suitable place for the construction of a road, the use of special geometric solutions that can help reduce the noise load on the surrounding areas, and the installation of soundproof barriers. A fairly effective means of combating the noise load from the highway is the installation of noise protection screens along the highway. They can be made of different materials, different in structural and geometric perspective. It has been studied that the most effective way to protect rural areas from traffic noise is the construction of screen houses along transport highways. According to the data, the noise level behind such buildings decreases to 23 dBA compared to the noise level on the transport highway itself. A noise map is used to determine the noise level in built-up areas as a whole and in individual sections of microdistricts, which is a graphical representation of sound pressure level curves plotted on a plan diagram. These maps make it possible to estimate the reduction of the noise level with distance from the transport highway.

Analysis of the movement of an empty car on the longitudinal profile of the hill

At present, in the existing methods for determining the height of a hump, the height is calculated based on the most difficult conditions - winter temperature and head wind, and a four-axle empty covered wagon is selected for a poor runner. Based on the basic law of dynamics (D’Alembert’s principle) as applied to weak links and the use of analytical formulas in the article, the calculation of the kinematic parameters of the movement of cars in the braking zone of the section of the first braking position of the hump is carried out. A sorting hump 3.08 m high is considered, for a four-axle empty covered wagon the winter temperature is -100, the headwind speed is 5 m/s m. When calculating the height of the marshalling yard, it is necessary to take the technical characteristics of a four-axle empty gondola car as a poor runner, since the headwind also acts inside the gondola car and prevents the car from rolling down the hill. It is recommended to study the effect of a headwind on a four-axle empty gondola car.

ОЦЕНКА РЕСУРСА ЭЛЕМЕНТОВ ТОРМОЗНОЙ СИСТЕМЫ

In this article, the influence of parameters during braking on the resource of the elements of the braking system, the operating conditions and the movement of cars are considered. A study was conducted to obtain the considered parameters in real operating conditions. A mathematical model has been developed for estimating and predicting the residual resource through the specific friction of braking mechanisms, taking into account operating conditions. The results obtained have practical application in maintenance to ensure the performance of the braking system with the correlation of the economic factor.

Характеристики транспортного затора на основе данных системы фото- и видеофиксации

The relevance of the present paper is justified by the need to search for a scientifically based criterion for the formation, development and elimination of traffic congestion using modern highly efficient mathematical methods of information processing. It seems necessary to study the results of using the rescaled range, statistical, fractal, harmonic, and wavelet analysis of time series formed by the time (duration) of the movement of cars in a stream along a road section in the absence and presence of traffic congestion. The object of study is a section of the road network equipped with a software and hardware complex that allows measuring the characteristics of any car in the flow of transport. The subject of the study is the patterns of changes in the duration of movement of individual cars in the absence and presence of a congestion situation. The purpose of this study is a quantitative indicator of the formation, evolution, and elimination of traffic congestion. The basis of the theoretical and methodological approach is the use of modern highly efficient mathematical methods for processing information about traffic flows received from stationary complexes of photo and video recording of traffic violations. As a result of the study of time series, decompositions of the analyzed time series by harmonics and wavelets are constructed, statistical and fractal characteristics of the time series under consideration are determined. The analysis of the obtained results is carried out, the features of the obtained dependencies are revealed. The theoretical and practical significance of the work lies in the scientific substantiation of the quantitative characteristics of traffic congestion, which is of practical interest from the point of view of predicting anomalies in the movement of vehicles on the road network, making decisions on managing the operation of traffic lights, etc. The direction of further research is an in-depth analysis of the identified indicator and determination on its basis of a criterion for determining the stages of formation, evolution, and elimination of traffic congestion at intersections of the street and road network of a large industrial city.

Valuation of the influence of the basic specific resistance to the movement of freight cars on the energy costs of driving a train

The primary specific resistance to the movement of freight wagons is a key parameter for normalizing the time and energy consumption of trains. Although the “Rules of Traction Calculations” calls for dividing wagons into six groups when calculating this resistance, in practice (using the traditional method), appropriate regulations are developed based on the separation of train wagons into two groups (4th and 8th lips). One of the main reasons for this is the inability to account for the unique features of each wagon in a given train. To address this issue, a program was developed for determining the necessary parameters of wagons for traction calculations based on their identification numbers. This software can be accessed through the website https://trainlocomotive.netlife.app/. Using this program, a method for calculating the primary specific resistance to the movement of freight wagons has been developed. Field sheets of freight trains moving through the Uzbekistan Temir Yullari railway station were analyzed. As a result, it was discovered that nearly half of the freight train composition consists of empty wagons, while the proportion of loaded gondola cars and tanks is 23%. The primary specific resistance to the movement of wagons in such a mixed composition is calculated using both traditional and developed methods. The impact of the primary specific resistance on the energy costs of maintaining the train is evaluated. As a result, the feasibility of utilizing the developed method for normalizing electricity consumption based on traction calculations is demonstrated.

FORMATION OF THE LOAD FROM THE VEHICLE ON THE ROAD SURFACE AT DIFFERENT SPEED OF OVERCOMING THE ROUGHNESS

To reduce the negative impact of the vehicle on the road surface, its maximum axle load is limited to the legal level. At the same time, when the car is moving on an uneven road, its dynamic load on the road surface can both exceed the static load by several times and decrease to zero (the separation of the wheel from the supporting surface). At the same time, the elastic tire is deformed in different directions, which is accompanied by forces and moments that are transmitted to the car's steering system and its suspension through the rim, disc and hub. This can lead not only to fluctuations in the sprung and unsprung mass of the car (affecting the smoothness of the ride, fuel economy, etc.) and changing its direction of movement (loss of stability and controllability) [1], but also to further destruction of the road surface. It is worth noting that the deviation of the values of the dynamic load of car wheels on the road surface from the static one largely depends on the speed of overcoming road irregularities. The article presents the results of theoretical studies of the motion of an average passenger car that overcomes road irregularities with its left-hand wheels. Different speeds for overcoming road irregularities were studied, starting with 30 km/h and ending with a speed of 120 km/h. The dependence of the change in the normal reactions of the support surface on the wheels of the car from the traveled distance was determined. In order to understand the formation of the load from the car on the road surface, an analysis of graphical dependencies describing the working processes of the suspensions of its wheels, which overcome road unevenness, was carried out. The obtained data allow us to analyze and evaluate the influence of the working processes of the suspension of the wheels of the car and the speed of overcoming road irregularities on the formation of the load acting on the road surface.

Application of calibrated vehicle dynamic indicators in city traffic management

The number of registered vehicles in the Russian Federation is increasing every year, and the traffic flows of cities consist mainly of cars. The car fleet of the Russian Federation has undergone significant changes in recent decades. In particular, passenger vehicles, their power and design parameters are improving every year. These changes affect the system and the process of movement of cars in the traffic flow. This article defines the parameters that affect the functioning of urban traffic flows and, in a mathematical way, on their basis, found dynamic indicators for a conditional “calibrated” car.

Calculation-empirical estimation of the vertical dynamic coefficient in the event of additional oscillations of the car

According to the results of derailment investigations, the ensuring of train traffic safety was found to be a paramount and urgent task. The growth of freight density and speed of movement on the railway network leads to a significant increase in the number of damaged wheels and rails and, as a result, to an increase in the level of force interaction during load transfer, which provokes the likelihood of a wagon derailment. The operation safety level of rolling stock on railways is determined mainly by the presence of a car derailment stability margin, which depends on the vertical dynamics and the coefficient kdv, which changes throughout the entire time of movement and, accordingly, on the technical condition of the car and the track as a whole. The vertical addition to each element of this “wheel-rail” system depends on many factors, therefore, the level of operational safety of the car, as a mechanical system, is determined mainly by its sprung and non-sprung car parts. The calculation schemes used to study the stability of unperturbed motion are non-linear systems. Non-linearities occur due to the gaps in axle boxes, side bearings and similar connections, non-linearity of the interaction forces of wheels with rails and, at present, also in some types of spring suspension. When moving in a curve, the cart is known to perform a complex movement. The rotation and transverse displacement of the bogie is prevented by frictional forces between the wheels and the rails. The bogie is affected by a part of the centrifugal force, unbalanced by the elevation of the outer rail and depending on the speed of movement, as well as by the guiding force from the side of the outer rail. It is known the process of a car movement results in the appearance of horizontal transverse (relative to the direction of movement) forces, which are determined by the level of interaction between the wheel flanges and the rails. The nature of the perturbed movement of the car leads to the appearance of horizontal transverse with respect to the axis of the path of movement. At relatively low speed, the forces that arise after wearing out of the gaps in the track and when the wheel flanges rest against the rail heads, at a certain level of irregularities, are not dangerous for the wheel-rail system. But with an increase in the speed of the car, these forces increase so that there is a threat to traffic safety as the likelihood of derailment increases.

Rethinking road network hierarchy towards new accessibility perspectives

Conventional road network hierarchy has focused mainly on facilitating car movement, while (usually) neglecting the rest surface transport modes. This fact resulted in dysfunctional urban environments where a plethora of social, economic and environmental issues are encountered. In this context, serious inequalities regarding urban mobility arise (e.g., inaccessible areas without car, exclusion of vulnerable social groups from a fair transport system, etc.). Therefore, there is an urgent need to bring forth the notion of accessibility and the fair access to opportunities, in transport systems and specifically in road network hierarchy.This study aspires to explore whether the rethinking/reformulating of the road network hierarchy can improve the accessibility level for sustainable modes (public transport and cycling/micromobility) in different transport future paths. To this end, 4 different scenarios that redefine the strategic road network of the study area are developed: 1) Business as Usual (BAU), 2) Car-oriented city, 3) Public Transport Priority, 4) Sustainable Modes Integration. Next, a combinatorial approach evaluating these scenarios is adopted: specifically, the spatial accessibility concerning cars, public transport and cycling/micromobility in each scenario is estimated. This method is applied to the metropolitan area of Athens, Greece which can be considered as a challenging example of a car-oriented metropolis. The main results indicate that the fourth scenario integrating all sustainable modes can improve the accessibility of public transport and cycling, while restraining car dominance in terms of access to opportunities. These findings are particularly useful for researchers and practitioners and could be taken into account for the making of human-oriented cities with a better level of mobility for all in the future.

Результаты кинетостатического исследования дорожной энергетической установки с ползунно-коромысловым преобразователем

The base factor of accidents with pedestrians is zero visibility as revealed by Russian auto statistic. Drivers have a poor view of pedestrians and crosswalk at twilight and night against road sign. Currently autonomous wind turbines and solar panels are used for improve of road safety. From another angle practice possibility of equipment type as road energy harvesting system is studying scientific collaboration. Operation of the systems is based on car motion energy conversion to electrical energy. The research goal is force determination acting in mechanism of road energy harvesting system. As a result of force study of road energy harvesting system, the forces in mechanical energy converter to electrical energy are determined when a car pass. On generator shaft torque is created equal 393 N∙m when typical car passes with 1600 kg mass by way road energy harvesting system from the performed calculations. Moreover, in generator resistive torque produces with value depending speed of moving car: at speed of 20 km/h the resistive torque is 115 N∙m; at speed of 30 km/h resistive torque is 260 N∙m; at speed of 40 km/h resistive torque is 390 N∙m. The energy amount saved by flywheel is directly proportional to speed and has values: at speed of 20 km/h energy is 47 J; at speed of 30 km/h energy is 105 J; at speed of 40 km/h energy is 165 J. The calculation data show that road energy harvesting system is operable with given parameters of construction elements.