Mathematical model of suspension of tracked vehicles

The purpose of the study is to increase the completeness and reliability of approaches to deter-mining the components of the cornering resistance a tracked vehicle, as well as to create a method for their assessment, which will be suitable for practical calculations. The article analyzes two components of the moment of cornering resistance of the tracked vehi-cle, which can be distinguished if we consider the interaction of the caterpillar with the support base through separate contact spots (active sections of the tracks located under the road wheels). The first component arises from the linear movement of the active sections of the tracks. The second is caused by the rotational movement of the contact patch about the vertical axis. The paper presents a mathematical model of the interaction of the propeller and a dense support base, which makes it possible to study the dependence of the components of the moment of corner-ing resistance on the geometric parameters of the undercarriage of a tracked vehicle. The horizontal reaction force in this case is presented as a function of the slip coefficient. The possibility of realiz-ing various adhesion qualities of the propulsion unit in the longitudinal and transverse directions of sliding is provided. The model assumes a preliminary division of the contact patch into a finite number of elementary areas. Since the number of elementary sites affects the result, the article con-ducted a study to determine the minimum number of sites to ensure acceptable accuracy. An analysis of the expressions available in the literature was carried out to determine the speci-fied component of the cornering resistance. The new empirical relationships that better agree with the mathematical model were proposed. The study of several existing tracked vehicles, differing in the mass and size of the track support surface, made it possible to conclude that it is advisable to take into account the moment of cornering resistance of the contact patch for various types of tracked vehicles.

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MATHEMATICAL AND PHYSICAL BASIS FOR DEVELOPING A SIMULATOR FOR TOWING AND PULLING OF WHEELED AND TRACKED MACHINES

Advanced Information Systems ◽

10.20998/2522-9052.2021.4.18 ◽

2021 ◽

Vol 5 (4) ◽

pp. 135-139

Author(s):

Alexander Serhieiev ◽

Andriy Krivoshapka ◽

Oleksandr Isakov ◽

Vyacheslav Lysenko ◽

Viktor Moskalenko ◽

...

Keyword(s):

Mathematical Model ◽

Physical Basis ◽

Design Parameters ◽

System Of Equations ◽

Aramid Fibers ◽

Tracked Vehicles ◽

General Scientific ◽

And Performance ◽

The Mathematical Model ◽

Physical Quantities

The subject matter of the article is the towing and pulling of wheeled and tracked vehicles with the use of cable ropes and dynamic slings. The goal of the study is to determine the mathematical and physical basis for the development of a simulator for towing and pulling wheeled and tracked vehicles for researching to study the possibility of using aramid fibers of cable-ropes and dynamic slings. The tasks to be solved are: based on the analysis of the main roads and ground characteristics to formalize the list of calculated parameters and physical quantities determine the amount of evacuation work when pulling, towing and transporting wheeled and tracked vehicles; to develop a mathematical model that describes the process of pulling and towing wheeled and tracked vehicles using cable ropes and dynamic slings. General scientific and special methods of scientific knowledge are used. The following results are obtained. By analyzing the main characteristics of roads and ground, a formalized list of design parameters and physical quantities that determine the volume of evacuation work during the towing and pulling of wheeled and tracked vehicles was obtained. Mathematical model, describes the process of pulling and towing wheeled and tracked machines using cable ropes and dynamic slings have been compiled as a system of equations with different order. analyzed existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles. Existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles have been analyzed. Conclusions. The main roads and ground characteristics that determine the vehicles. evacuation conditions are the following: the type of road or ground, their possibility depending on the season and precipitation, the presence of ascents and descents, as well as the nature of road (ground) interaction with caterpillars determined by resistance coefficients. movement and traction. The mathematical model of pulling a wheeled and tracked vehicle using cable ropes and dynamic can be presented as a system of equations: the jerk carried out by the machine in time reflected third-order differential equation, assuming that all the energy accumulated by the cable is numerically equal to the work of moving stuck machine, corresponds to the equality of the corresponding integrals; the properties of aramid fibers that affect the strength and performance characteristics of cable ropes can be formally expressed through the elongation of the cable. Analysis of strength and service properties of aramid fibers opens the way to improvement of manufacturing technology of cable ropes and dynamic slings for pulling and towing of wheeled and tracked vehicles.

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Analytical Study on the Cornering Behavior of an Articulated Tracked Vehicle

Machines ◽

10.3390/machines9020038 ◽

2021 ◽

Vol 9 (2) ◽

pp. 38

Author(s):

Antonio Tota ◽

Enrico Galvagno ◽

Mauro Velardocchia

Keyword(s):

Mathematical Model ◽

Degrees Of Freedom ◽

Analytical Study ◽

Proportional Integral Derivative ◽

Vehicle Model ◽

Tracked Vehicle ◽

Tracked Vehicles ◽

Side Slope ◽

Skid Steering ◽

And Control

Articulated tracked vehicles have been traditionally studied and appreciated for the extreme maneuverability and mobility flexibility in terms of grade and side slope capabilities. The articulation joint represents an attractive and advantageous solution, if compared to the traditional skid steering operation, by avoiding any trust adjustment between the outside and inside tracks. This paper focuses on the analysis and control of an articulated tracked vehicle characterized by two units connected through a mechanical multiaxial joint that is hydraulically actuated to allow the articulated steering operation. A realistic eight degrees of freedom mathematical model is introduced to include the main nonlinearities involved in the articulated steering behavior. A linearized vehicle model is further proposed to analytically characterize the cornering steady-state and transient behaviors for small lateral accelerations. Finally, a hitch angle controller is designed by proposing a torque-based and a speed-based Proportional Integral Derivative (PID) logics. The controller is also verified by simulating maneuvers typically adopted for handling analysis.

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The Research on Grounding Pressure Distribution of Tracked Travelling Mechanism

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.526.115 ◽

2014 ◽

Vol 526 ◽

pp. 115-120

Author(s):

Xi Yang Liu ◽

Zhi Yong Jiao ◽

Mei Yu Zhang

Keyword(s):

Mathematical Model ◽

Pressure Distribution ◽

Center Of Gravity ◽

Core Region ◽

Tracked Vehicles ◽

Overall Design ◽

Ground Pressure ◽

Ground Conditions ◽

The Mathematical Model

The grounding pressure of tracked vehicles is closely related to the overall structure of the vehicles and the ground conditions, and its distribution is more complex and changes in the different center of gravity. So in this paper, under certain assumptions, we derive the mathematical model of the grounding pressure distribution through analysis and research, which can predict the ground pressure distribution of tracked vehicles at any moment. By analyzing the tracked grounding pressure distribution, we put forward the concept of core region of track connecting with the ground, and some meaningful conclusions and formulas for the overall design of tracked vehicles.

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Mathematical model for assessing lateral stability of articulated tracked vehicles

Journal of Physics Conference Series ◽

10.1088/1742-6596/2094/4/042005 ◽

2021 ◽

Vol 2094 (4) ◽

pp. 042005

Author(s):

A P Chajkin ◽

R Yu Dobretsov ◽

V A Sokolova ◽

I A Teterina ◽

A V Kamenchukov ◽

...

Keyword(s):

Mathematical Model ◽

Critical Speed ◽

Center Of Mass ◽

Lateral Force ◽

Operational Reliability ◽

Lateral Stability ◽

Steering Control ◽

Tracked Vehicles ◽

Propulsion Unit ◽

Empirical Coefficients

Abstract The article considers the problem of increasing transport productivity, operational reliability and safety during cargo transportation by using articulated tracked vehicles and road trains with active trailers. The influence of the introduction of an electromechanical drive, the modernization of the propulsion unit and the steering control system on the lateral stability of an articulated tracked vehicle is analyzed. A mathematical model is described for calculating the lateral stability of the chassis of articulated tracked vehicles used in the regions of the Far North, Arctic and Antarctic. The model is based on developments carried out for the chassis of an articulated wheeled vehicle. The model allows calculating to determine the key geometric and kinematic parameters of the rotation, taking into account the action of external forces. The use of holonomic constraints in determining the critical speed of movement is determined by the physical picture of the beginning of overturning, which corresponds to the achievement of the critical folding angle of the sections. This approach makes it possible not to use empirical coefficients when assessing the instantaneous position of the center of gravity of the system, the center of rotation, the radius of rotation of the center of mass, and the critical speed of the chassis. The moment of the beginning of the rollover is determined by the disappearance of the normal reaction under the link caterpillar. The onset of lateral sliding is determined by the lateral force exceeding the lateral adhesion limit.

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