scholarly journals Influence of Clearance on the Rocker Arm Pin on the Steerability and Stability of the Vehicle Motion

Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7827
Author(s):  
Krzysztof Parczewski ◽  
Henryk Wnęk

The article presents an analysis of the impact of a malfunction resulting from excessive clearance on the rocker arm pin of the front suspension on the vehicle’s steerability. The first part of the article presents an analysis of the influence of the clearance on the rocker arm pin on the geometry of the suspension and steering system. The occurrence of forces acting on the rocker arm pin in various phases of the vehicle motion was analyzed. To assess the vehicle’s steering, the vehicle’s response time to sudden steering wheel movement was used. The vehicle’s response time to sudden movement of the steering wheel was used to assess the vehicle’s steerability. The second part presents the results of bench tests and traction tests of a vehicle equipped with a specially made measuring rocker arm with the possibility of simulating a clearance. The tests were carried out on a class B passenger car in selected road tests. The results of measurements obtained for the roadworthy vehicle and the vehicle with the rocker arm with clearance were compared. The influence of the clearance on the rocker arm pin on the change of vehicle steerability in steady and dynamically changing conditions was analyzed. The test results show the effect of clearance on vehicle steering and on the vehicle steerability. The study tried to determine to what extent the clearance on the rocker arm affects the vehicle’s steerability and thus the safety in road traffic.

2021 ◽  
Vol 334 ◽  
pp. 02018
Author(s):  
Fedor Smolenkov ◽  
Igor Blyankinshtein

The possibility of vehicle steering system diagnosis based on analysis and visualization data processing is considered. The video recording method for the diagnostic troubleshooting of steering system and front suspension group is proposed. The method provides for placement of the motor vehicle on the diagnostic station, with further webcamera installation for measuring the steering wheel rotation angle and clear contract marking on the steering joint under experiment, setting the webcamera to fix and record the beginning of the movement steering joint under experiment, the video registration of the steering test results and further video processing using dedicated software. The outcomes of the evaluation of the method is delivered.


Author(s):  
Mishank Sharma ◽  
◽  
Rakesh Chander Saini ◽  
Ramakant Rana

Suspension is a system of tires, springs, shock absorbers, and linkages that connects a vehicle’s chassis to its wheels and allows relative motion between the two. Steering is a mechanism that provides a direction to the vehicle, it basically consists of gears, shaft, joints, steering column, steering wheel, and furthermore. The main objective of this paper is to design a system of suspension and steering for a three-wheeled human-electric hybrid trike. A system of directly actuated double wishbone suspension system is chosen for the front and a pushrod actuated 2-link trailing arm suspension system for the rear. The steering system used is a type of Single tie rod and drag link system. A knuckle-to-knuckle drag link provides continuity to the wheels and a tie rod to the bell crank provides steering rotation. This paper also talks about the single nut hub-shaft system which is being used in the front suspension system. Based on the research using various input parameters, the inboard and outboard suspension hardpoints are decided to maximize the tire contact patch at every vehicular motion (mainly during body roll). Forces and stresses are calculated with the help of Free Body Diagrams (FBD) and Multi-Body Dynamics (MBD) software LOTUS Shark. The paper discusses the calculations regarding the roll and ride rates and for the custom springs of specific stiffness used in front and rear shock absorbers and the variation of roll steer and bump steer on changing various parameters of the steering system. Key points also include the procedure of selections of various types of bearings, rod ends, and bolts. This paper also talks about laser-cut jigsaw uprights that are used in the front wheel assembly. The finite element method was used to analyze the designs using DS Solidworks and Ansys Workbench. Static structural and explicit dynamics analysis was performed on the wheel assembly components both individually and assembled


2020 ◽  
Vol 128 ◽  
pp. 71-80
Author(s):  
Piotr Malawko ◽  
Marcin Ślęzak

The article describes research related to detecting the feeling of premature fatigue while driving by disabled people. Based on the analysis of the literature on driving by drivers with a significant degree of disability, and based on the authors' experience, two groups of drivers were selected: with paraplegia and tetraplegia. The tests were carried out on vehicles equipped with devices of the following types: handle mounted on the steering wheel, the mechanism for manual operation of gas and brake, automatic gearbox. To identify the phenomenon of premature fatigue, we proposed its definition, measures, and two detection methods. Some measures were quantitative, for example, the number of occurrences of the phenomenon in a given statistical sample, while others were qualitative, for example, the time of occurrence since the beginning of driving. Test methods included driving in real traffic and on the maneuvering yard. Tests conducted in road traffic showed the actual time of occurrence of the studied phenomenon. On the other hand, experiments on the maneuvering area aimed at intensifying operations performed by the driver and, as a result, reducing the time of examination. The assessment of the correctness of the results of the presented method of detecting the feeling of premature fatigue consisted of (i) assessing the convergence of test results from road tests and the maneuvering yard, (ii) compliance of the assessment of the tested devices using individual measures of the studied phenomenon and (iii) comparison of the current test results with the reputation of devices on the market. The research allowed us to identify adaptive devices that caused the feeling of premature fatigue to the most significant and lowest extent. On this basis, in a properly selected research sample of drivers with disabilities, the ergonomics of individual devices can be assessed. At the same time, using the single-person method, you can evaluate the appropriateness of the device selection for a given driver. W artykule opisano badania związane z wykrywaniem odczucia przedwczesnego zmęczenia podczas prowadzenia pojazdu przez osoby niepełnosprawne. Na podstawie przeprowadzonej analizy literatury dotyczącej problematyki prowadzenia pojazdów przez niepełnosprawnych kierowców ze znacznym stopniem niepełnosprawności oraz na podstawie doświadczenia Autorów, wytypowano dwie grupy kierowców: z paraplegią i tetraplegią. Badania przeprowadzono na pojazdach wyposażonych w urządzenia następujących typów: uchwyt zamocowany na kole kierownicy, urządzenie do ręcznej obsługi gazu i hamulca, automatyczna skrzynia biegów. W celu identyfikacji zjawiska przedwczesnego zmęczenia opracowano: definicję zjawiska, jego miary możliwe do wykorzystania w badaniach oraz dwie metody wykrywania. Niektóre miary miały charakter ilościowy, na przykład liczba wystąpień zjawiska w określonej próbie statystycznej, a inne jakościowy, na przykład czas wystąpienia od momentu rozpoczęcia prowadzenia pojazdu. Metody badań obejmowały prowadzenie pojazdu w rzeczywistym ruchu drogowym oraz na placu manewrowym. Testy prowadzone w ruchu drogowym pokazywały rzeczywisty czas pojawiania się badanego zjawiska. Natomiast eksperymenty na placu manewrowym miały na celu intensyfikację wykonywanych przez kierowcę operacji i w efekcie skrócenie czasu badania. Ocena poprawności wyników prezentowanej metody wykrywania odczucia przedwczesnego zmęczenia polegała na: ocenie zbieżności wyników badań z testów drogowych i z placu manewrowego, zgodności oceny badanych urządzeń za pomocą poszczególnych miar badanego zjawiska oraz zbieżności wyników badań z renomą poszczególnych urządzeń na rynku. Przeprowadzone badania pozwoliły na identyfikację urządzeń adaptacyjnych, które w największym oraz najmniejszym stopniu powodowały odczucie przedwczesnego zmęczenia. Na tej podstawie, w odpowiednio dobranej próbie badawczej kierowców z niepełnosprawnościami można oceniać ergonomię poszczególnych urządzeń. Jednocześnie, przy zastosowaniu metody dla pojedynczej osoby, można oceniać słuszność indywidualnego doboru urządzeń dla danego kierowcy.


2021 ◽  
Vol 1 (50) ◽  
pp. 210-220
Author(s):  
LEW K ◽  

The steering system in a vehicle is one of the main systems that ensures its controllability and is important for road safety. The steering system consists of two main mechanisms, namely the steering gear, the task of which is to convert the rotary motion into reciprocating motion, and the steering gear, the task of which is to ensure the correct steering of the vehicle. In this case, the steering system is interconnected with the suspension of the car, in which there are four main angles of the wheels that are responsible for the correct maneuverability of the vehicle, namely: camber angle, toe angle, angle of rotation of the axle of the fist and the angle of inclination of the pivot axis of the fist. Measuring the geometry of a vehicle's suspension has several interrelated purposes. One of them is the modification of the stability of the vehicle, that is, the effective impact on the maintenance of the vehicle on the road. Handling also depends on the geometry setting and ensures proper maintenance on the road. Well adjusted geometry ensures even tire wear on each axle. The purpose of the steering system is to maintain the correct position of the steering wheel in relation to the steering wheels. The tests were carried out in stationary conditions at the diagnostic station of the Rzeszow University of Technology using an automatic device for measuring and regulating the air pressure in the tires of the Unitrol PA-10K car and the Launch X-631 car wheel alignment system. The object of the study was a passenger car of the Opel Agila brand. The tests were carried out for various values of air pressure in the car wheels. Based on the above, the task was set - to demonstrate how incorrect air pressure in the wheels of a car changes the angles of inclination of the wheels of the car. When analyzing the obtained test results, it was found that the pressure in the wheels, different from the nominal, but the same in each wheel, does not significantly affect the change in the values of the parameters of the angles of inclination of the vehicle wheels. If the pressure in the wheels on one side of the vehicle drops by 1 bar, there is a significant difference in the camber angles of the front axle. Changes in the air pressure in one of the rear wheels of the car do not significantly affect the angles of inclination of the car wheels. KEY WORDS: AIR PRESSURE IN THE WHEELS, UNEVEN PRESSURE, WHEEL MOUNTING ANGLES, CAMBER AND TOE ANGLES, STEERING.


2019 ◽  
Vol 254 ◽  
pp. 04001
Author(s):  
Marian Dudziak ◽  
Andrzej Lewandowski ◽  
Michał Śledziński

Disturbances in the vehicle motion may be caused by different factors and in many cases are the reason for dangerous traffic incidents. Disturbances within the human-vehicle system are particularly hazardous. An innovative method was designed for analyzing and simulating the process of loss of vehicle motion stability after interference in the steering system, e.g. by acting on the steering wheel by the passenger. The subject of the study is the theoretical and experimental analysis of the vehicle motion path kinematics together with the duration of the disturbance, driver’s reaction time and steering wheel turning angles. PC-Crash simulation software was employed for the purpose of studying the disturbance characteristics and their influence on the loss of vehicle motion stability. It is recognized that the studied issues are as yet poorly understood, the presented results expand our knowledge base in this area and can be employed for the purpose of analysis of actual traffic accidents.


Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6740
Author(s):  
Włodzimierz Choromański ◽  
Iwona Grabarek ◽  
Maciej Kozłowski

The subject of this article is the design of a nonstandard steering system in cars. The applied methodology takes into account universal design, ensuring the greatest possible adaptation of the steering system to potential users, and at the same time, thanks to the specific nature of the designed steering device, it also assumes a special approach allowing for individual adjustment of the steering system to the needs and limitations of drivers with lower-limb disabilities. It is implemented through the “custom design” methodology. This article presents the impact of the design features of the multifunction steering wheel on the correctness of driving, as well as the level of load on selected muscles of the upper limbs responsible for operating the steering wheel. The tests were carried out on a dynamic simulator of a motor vehicle using the electromyography (EMG) technique, which enables the measurement of muscle load. A systemic approach to training and verifying the skills of drivers using new HMI solutions is proposed.


Energies ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6940
Author(s):  
Marek Guzek ◽  
Zbigniew Lozia

All over the world, the vehicles introduced now into the market are usually provided with EDRs (Event Data Recorders), intended to measure and record the parameters that characterise the vehicle motion in the pre-, during-, and post-accident phases. The EDRs are to facilitate the description and reconstruction of possible road accidents. They are patterned on aircraft “black boxes” (flight recorders). Many of them have simplified design, disregarding three (of six) vector components that describe the motion of the vehicle body solid. In the paper presented, the authors used simulation models built by themselves to represent motor vehicle dynamics and the reconstruction of vehicle trajectory and velocities based on records obtained from two EDR types: “aircraft” one (EDR1) and “simplified” one (EDR2). Using a simulation method, they examined the impact of the said simplifications mentioned above on the quality of reconstruction of vehicle motion for four typical manoeuvres in road traffic. The calculation results obtained for input data adopted to rep-resent a medium-class passenger car have shown that the simplifications may cause considerable reconstruction errors. This particularly applies to the manoeuvres where significant changes took place in the roll and pitch angles of the vehicle body solid (to which the EDR was fixed) or where the changes were characterised by absence of symmetry in the parameters that describe the manoeuvre and by the constant sign of the vehicle body roll angles.


2016 ◽  
Vol 823 ◽  
pp. 187-192 ◽  
Author(s):  
Oana Victoria Oţăt ◽  
Nicolae Dumitru ◽  
Victor Oţăt

The present underpins a computer-assisted investigation regarding the driver’s behavior and the injuries suffered in frontal vehicle collision, more precisely the injuries suffered in the thorax area. Hence, by means of the LS-Dyna software package we have carried out two series of virtual simulations with a dummy positioned on the driver’s place, i.e. belted and unbelted. For the simulation we have selected a Hybrid III 5th percentile female dummy. Aiming at achieving a simulation that would display a high accuracy degree with respect to the driver’s kinematic behaviour at the impact moment, our complete model also included, besides the dummy, the elements in the habitable: the seat, the seat belt, the steering wheel, the airbag and the dash board. Thus, the focus of the undertaken study was to establish the accelerations in the driver’s thorax area as well as the injury degree, expressed by the CSI (Chest Severity Index). The results obtained validated our hypothesis in that passive safety systems, i.e. the seat belt, diminish considerably the driver’s injuries degree in case of a road traffic accident.


Author(s):  
Larisa Dmitrievna Popovich ◽  
Svetlana Valentinovna Svetlichnaya ◽  
Aleksandr Alekseevich Moiseev

Diabetes – a disease in which the effect of the treatment substantially depends on the patient. Known a study showed that the use of glucometers with the technology of three-color display of test results facilitates self-monitoring of blood sugar and leads to a decrease in glycated hemoglobin (HbAlc). Purpose of the study: to modeling the impact of using of a glucometer with a color-coded display on the clinical outcomes of diabetes mellitus and calculating, the potential economic benefits of reducing the hospitalization rate of patients with diabetes. Material and methods. Based on data from two studies (O. Schnell et al. and M. Baxter et al.) simulation of the reduction in the number of complications with the use of a glucometer with a color indication. In a study by O. Schnell et al. a decrease of HbA1c by 0.69 percent is shown when using the considered type of glucometers, which was the basis of the model. Results. In the model, the use of a glucometer with a color-coded display for type 1 diabetes led to a decrease in the total number of complications by 9.2 thousand over 5 years per a cohort of 40 thousand patients with different initial levels of HbA1c. In a cohort of 40 thousand patients with type 2 diabetes, the simulated number of prevented complications was 1.7 thousand over 5 years. When extrapolating these data to all patients with diabetes included in the federal register of diabetes mellitus (FRD), the number of prevented complications was 55.4 thousand cases for type 1 diabetes and 67.1 thousand cases for type 2 diabetes. The possible economic effect from the use of the device by all patients with a diagnosis of diabetes, which are included in the FRD, estimated at 1.5 billion rubles for a cohort of patients with type 1 diabetes and 5.3 billion rubles for patients with type 2 diabetes. Conclusion. Improving the effectiveness of self-monitoring, which is the result of the use of glucometers with color indicators, can potentially significantly reduce the incidence of complications in diabetes and thereby provide significant economic benefits to society.


2021 ◽  
Vol 10 (2) ◽  
pp. 34
Author(s):  
Alessio Botta ◽  
Jonathan Cacace ◽  
Riccardo De Vivo ◽  
Bruno Siciliano ◽  
Giorgio Ventre

With the advances in networking technologies, robots can use the almost unlimited resources of large data centers, overcoming the severe limitations imposed by onboard resources: this is the vision of Cloud Robotics. In this context, we present DewROS, a framework based on the Robot Operating System (ROS) which embodies the three-layer, Dew-Robotics architecture, where computation and storage can be distributed among the robot, the network devices close to it, and the Cloud. After presenting the design and implementation of DewROS, we show its application in a real use-case called SHERPA, which foresees a mixed ground and aerial robotic platform for search and rescue in an alpine environment. We used DewROS to analyze the video acquired by the drones in the Cloud and quickly spot signs of human beings in danger. We perform a wide experimental evaluation using different network technologies and Cloud services from Google and Amazon. We evaluated the impact of several variables on the performance of the system. Our results show that, for example, the video length has a minimal impact on the response time with respect to the video size. In addition, we show that the response time depends on the Round Trip Time (RTT) of the network connection when the video is already loaded into the Cloud provider side. Finally, we present a model of the annotation time that considers the RTT of the connection used to reach the Cloud, discussing results and insights into how to improve current Cloud Robotics applications.


Sign in / Sign up

Export Citation Format

Share Document