Development of spring torsion bar type negative stiffness damping device and applied research

Mini-tiller is the most commonly used machine for agricultural production in hilly areas of our country the traditional micro-tiller will produce strong vibration during the working process, which will cause physical injury to the operator while reducing the reliability of the micro-tiller. In response to this problem, a technical solution for arranging a spring torsion bar type negative stiffness vibration damping device on the tiller was proposed, and a spring torsion bar type vibration damping device with stable mechanical performance, economical and practical, and negative stiffness characteristics was developed. A mathematical model of the vibration source of the micro-tiller was established to analyze the vibration parameters of the micro-tiller. On this basis, SolidWorks is used to carry out three-dimensional modeling of the tiller and the vibration reduction device, and Adams is used for vibration simulation analysis. The vibration parameter curve before and after the addition of the vibration reduction device at the handle of the tiller is collected and mathematically analyzed. The results show that the spring torsion bar type negative stiffness damping device has a good damping effect, and the damping rate for displacement in the x, y, and z directions are all above 30%.

Enhancement of Vehicle Dynamics with Application of H Arm at Rear Suspension System

The conventional design and manufacturing of rear suspension system in All terrain Vehicles were Double wishbone, Semi trailing arm, Mcpherson strut and torsion bar but to overcome the adverse effects such as wheel wobbling, Uncontrolled Toe and power losses from transmission. So by introducing a H-arm suspension system at the rear end of the vehicle can improve the performance of the vehicle by keeping it stable and able to sustain all the incoming loads from the ground and provides a comfortable drive and by maintaining a constant Toe which will improve the transmission. The primary objective of the suspension system in the ATV is to maximise the contact between the tires and the road surface, providing good handling and steering stability, evenly distributed weight throughout the vehicle and ensuring riders safety also comfort by absorbing the shocks from the terrain. Ansys solver is used for analysis, lotus shark used for the simulation and the modelling is done by using Solidworks 19. Fabrication of the system was done according to the Design values, run- virtual compliance test is performed for checking the vehicle dynamics.

Mathematical modeling of loading of heavy-class robotic complexes on a tracked chassis into transport aircraft of EMERCOM of Russia

Рассмотрен один из возможных подходов к математическому моделированию загрузки робототехнического комплекса (РТК) тяжелого класса на гусеничном шасси с независимой торсионной подвеской в транспортный самолет. Данный подход представляет собой часть обоснованной оценки авиатранспортабельности специальных РТК. Он базируется на построении и решении системы линейных уравнений, в результате чего определяются параметры, по которым оценивается факт «вписывания» конструкции образца РТК в размеры грузовой кабины самолета. Актуальность статьи обусловливается, во-первых, потребностью в создании специальных РТК тяжелого класса для применения при тушении пожаров на особо опасных объектах, во-вторых, значительным вкладом оценки возможностей по загрузке в самолеты РТК в априорную аналитическую оценку авиатранспортабельности специальных РТК как до создания опытных образцов, так и в ходе оперативной подготовки к перебазированию в районы чрезвычайных ситуаций и, в третьих, определенной сложностью графоаналитического моделирования рассматриваемой загрузки. The threat of man-made danger with such sources as accidents at radiation, chemical and explosive objects exists at present time. That’s why it is advisable to create heavy-class fire robotic complexes on a tracked chassis, as the most effective means of extinguishing fires in these conditions. The consequences of emergencies depend on a quick and timely response. Therefore, when creating the new promising fire equipment, one of the most important issues to be addressed is to ensure its air transportability. At the stage of development of advanced heavy-class fire-fighting robotic systems on a tracked chassis with the planned possibility of their air transportability, it is very important to perform an a priori assessment of this property before creating a prototype. Modeling of loading involves solving a variety of problems, the main and most complex of which is the calculation of the spatial position of the structure of a particular robotic complex model with a tracked chassis relative to the internal contours of the cargo cabin of the aircraft. There are several types of structures for springing support rollers of tracked chassis. This article discusses tracked chassis with independent torsion bar suspension widely used in modern military equipment. It is advisable to focus the development of heavy-class fire robotics on the use of torsion bar suspension. The calculation of parameters that form the basis of mathematical modeling consists in solving a system of nonlinear equations (including algebraic and trigonometric operations). One of the equations describes the condition of the equilibrium of forces, the second - the equilibrium of moments, the rest (according to the number of support rollers minus one) describe the conditions for the location of the torsion axes on a given construction axis. The proposed calculation method provides for the transformation of this system into a system of linear algebraic equations which ensure an approximate solution, and the organization of an iterative process that ensures the convergence of a sequence of approximate solutions to the solution of the original system of nonlinear equations. The approach presented in the article can be used as the basis for modeling the loading of a special robotic complex on a tracked chassis with an independent torsion suspension into the cargo cabin of a transport aircraft. In turn, this modeling allows us to perform the reasonable a priori assessment of the air transportability of the robotic complex, carried out both at the stage of layout of the sample during its creation and during operation.

Results of computer modeling of a modular independent tubular suspension of a logging truck

The necessity of increasing the efficiency of timber trucks by improving the designs of their suspensions has been substantiated. The main disadvantages of traditional suspension structures used in modern logging trucks have been described. A promising design of a modular independent tubular torsion bar suspension for a logging truck has been proposed. The aim of the research consisted of two stages. At the first stage, a mathematical model for the functioning of the proposed torsion bar suspension has been developed. At the second stage, a computer program for a preliminary assessment of the effectiveness of the functioning of this suspension (when driving on an insufficiently equipped forest road) has been made. Time dependences of the angular positions of suspension arm fork and ends of the tubular torsion bars were obtained. The regularities of the influence of the movement speed, average height of irregularities, coefficient of dry friction on the relative spread of vertical loads and suspension indicators of vibration dispersions were revealed.

Impedance Control Considering Velocity Saturation of a Series Elasticity System with a Motor

Human-machine cooperative robots are required to drive their arms with low impedance and high torque. As a compact mechanism that generates a large torque and has low impedance characteristics, the series elastic drive system, in which an elastic element is inserted between the motor and driving unit, has been proposed. In this paper, we propose a method of applying impedance control to a series elasticity system with a torque-compensating motor that uses a torsion bar as an elastic body that enables its use under high loads. The stability of the system was verified via simulation and experiment by considering the allowable speed and maximum torque of the motor. The experimental results from the conventional system and the proposed system were compared. The proposed system was confirmed to be superior to the conventional system in terms of both stability and tracking performance. Consequently, the effectiveness of our proposed system was confirmed.

Modernization of spring suspension of trailed vehicles

This article presents materials related to the development of a promising design of adaptive torsion bar suspension for trailed special and cargo vehicles, both trailers and semi-trailers, designed for the transportation of bulk and general cargo. A number of technical solutions, created at the level of inventions, are proposed, which make it possible to simplify the existing types of spring suspensions, reduce their metal consumption, improve the smoothness of trailed vehicles (TV) and increase their operational reliability due to the operation of suspensions in automatic mode. when they overcome micro and macro unevenness of the roadway. Analytical studies were carried out with the development of a design scheme and a methodology for calculating the design of an adaptive torsion spring for static and dynamic strength.

Calculation strength of torsion bar suspension of micromirrors (MEOMS)

The paper considers the strength calculation of the torsion bar suspension of a micromirror with a reflective layer of high optical quality of the surface for deflecting the reflected laser beam. By changing the angle of inclination of the micromirror, the laser beam enters the various input channels of the optical sensor. In this case, a control signal is generated for the further operation of the microcircuit. Thus, the micromirror performs the function of a switch for input optical channels connecting certain input or output elements of the microcircuit in various combinations for further processing. In this work, the calculation of the strength parameters of the mechanical structure of a micromirror made of various materials has been carried out. Practical recommendations related to the development of micromirror torsion bar suspension are given