Boom System Research Articles

Research on the change of the combined moment of inertia for two-link manipulator with angular coordinate system

The main of the problems of the development of two-link manipulators with an angular coordinate system is the lack of effective and universal control systems capable of implementing energy-intensive modes of movement. This is due to the design features of the pointer system of such manipulators and the methods of their use. During the operation of the manipulator, significant dynamic loads occur in its drive system, which create oscillations of the mechanical system and reduce the accuracy of work. The control system must also effectively compensate for such dynamic variations. Dynamic equations of motion used to build manipulator control controllers, which allow taking into account various features of using manipulators. These mathematical models necessarily contain one of the characteristics in the form of the combined moment of inertia of the mechanical system, which is important in the calculation of differential equations and the determination of kinematic parameters of motion. In this article, the combined moments of inertia of the boom system of a two-link manipulator with an angular coordinate system are determined. A study was carry out and it shown that the nature of the change in the combined moments of inertia influenced by the modes of movement of the boom system links. The results of the study showed that the combined moment of inertia of the boom system of the manipulator is not a constant value, which does not change uniformly under special operating conditions of the machine. To determine the combined moments of inertia, the method of bringing the kinetic energy of the moving system to the drive mechanism was apply. This is relevant, because in the future it will be necessary to adjust the unevenness of the movement of the manipulator links by the drive itself. The study was conduct for a typical linear motion mode and a motion mode with a change in speed along a parabolic trajectory.

Research of telescopic variable Boom length system for flat Boom tower crane

The telescopic principle of its boom section is investigated using the luffing system of the horizontal lifting boom with telescopic operation as the aim. In order to ensure that the normal lifting and luffing work of the trolley can be ensured when the horizontal boom is telescoped and retracted, the support method of the rope system on the horizontal boom, including the lifting rope system, the luffing rope system, and the telescopic rope system, is studied. The procedure for locating the supporting pulley of the three rope systems is investigated, and the alteration in the length of the three ropes caused by the extension or contraction of the horizontal boom is examined. The boom system's force analysis is conducted, and the force expressions of each force member with the expansion and contraction of the boom are obtained, and the force state diagram of each force member is drawn by MATLAB software.

Optimization of the mode of movement of the boom system of the loader crane

The article presents a method for solving the problem of eliminating vibrations of the load, which is fixed on a rigid articulated suspension at the time of simultaneous movement of two links of the boom system. The essence of the method is to optimize the mode of simultaneous movement of two links of the boom system of the loader crane with horizontal movement of the load during the start-up period. The problem is solved according to two optimization criteria, namely: according to the optimization criterion of the root-mean-square value of the generalized force and the optimization criterion of the root-mean-square value of the power of drive mechanisms. The developed criteria reflect the undesirable properties of the links of the boom system and drive mechanisms, so their value was minimized.
 The solution of the optimization problem is presented in a discrete form. For this purpose, the particle swarm optimization (ME-PSO) method was used. This helped to obtain discrete values of the kinematic and power characteristics of the boom system of the loader crane.
 Since the optimization criterion is an integral functional, the methods of the calculus of variations are used for its optimization. The solution of the variational optimization problem is presented in the form of many parametric functions that satisfy the boundary conditions of motion and minimize the obtained dimensionless criteria. For this purpose, the particle swarm optimization (ME-PSO) method was used. This made it possible to obtain the dependence of the optimal energy and power characteristics of the boom system and the drive mechanisms of the loader crane. The mode of movement of the boom system links obtained as a result of optimization improved the power and energy characteristics of the loader crane, which made it possible to increase its reliability and productivity.

Optimal mode movement of the robot manipulator on an elastic base according to the criterion of the mean square value of the acceleration of the drive torque

Previous studies of the optimization of the manipulator motion mode on an elastic base based on the criteria of the rms value of the drive torque and the rate of change of the rms value of the drive torque established that the use of optimal manipulator motion modes, which are created on the basis of higher derivatives of the characteristics of the change of the drive torque, allow to obtain more smooth movements of the boom system of the manipulator, thereby reducing its oscillations on the elastic support. At the same time, the obtained optimal modes of movement didn't completely eliminate the boom system oscillations during the change of departure. By observing the oscillations of the elastic link of the manipulator, the quality of the obtained optimal modes of movement was evaluate and the presence of residual oscillations was shown.
 This work considers the possibility of optimizing the manipulator's motion mode based on the criterion of the mean square value of the acceleration of the drive torque change. For this purpose, the second derivative of the driving torque function of the manipulator boom system drive was determined first. Such a criterion for optimizing the motion mode is an integral functional, the minimization of which is carry out by the methods of variational calculus. The regularity of the change of the driving torque it was find from the dynamic equation of motion.
 The search for the optimal motion mode of the manipulator realized through the solution of the Poisson boundary nonlinear differential equation of the fourth order.
 The results of the conducted research made it possible to clarify much better the nature of the vibrations of the manipulator boom system and, as a result, to develop a drive control system that allows the realization of the obtained optimal mode of movement.

Dynamic analysis of the joint movement of the hoisting and slewing mechanisms of a boom crane

To increase the productivity of boom cranes, the operation of individual mechanisms is combined. At the same time, dynamic loads on structural elements, drive mechanisms and loads on a flexible suspension increase, which reduces the reliability of crane operation and increases energy losses. Therefore, the research aims to consider the problem of the dynamics of the joint movement of the mechanisms for load slewing and hoisting of a boom crane. To study the dynamics of the joint movement of the mechanisms, the boom system was represented by a mechanical system with 6DOF, where the basic movement of the mechanisms and the oscillatory movement of the structural links with elastic and dissipative properties, as well as the load on a flexible suspension in the plane of crane slewing and hoisting were considered. For such a mechanical system of a crane, the differential equations of the joint motion of the crane slewing and hoisting mechanisms were developed. The obtained equations are a system of the second order nonlinear differential equations, for solving which a numerical method in the form of a computer program was used. Using the developed program, the dynamics of the joint movement of the mechanisms of a jib crane with specific numerical parameters were calculated. Based on the calculations, a dynamic analysis of the joint movement of the mechanisms for slewing and hoisting the load of a jib crane with a hoisting boom was carried out, which revealed high-frequency vibrations of links with elastic and dissipative properties, as well as low-frequency oscillations of the load on a flexible suspension. The greatest impact of oscillations is observed during the start-up of mechanisms, where high-frequency oscillations dampen during the transient process, and low-frequency oscillations dampen over a fairly significant period. To improve the dynamic properties of the mechanisms for turning and hoisting a load during their joint movement, it is proposed to optimise the mode of movement in the areas of transient processes (start-up, braking). The research results can be used in the development and operation of cranes in mechanical engineering, construction, and other industries

Dynamic Simulation Analysis of Truck Crane Based on ADAMS

Background: With a reduction in the weight of telescopic boom crane and an increase in its lifting capacity, the contradiction between its speed, stability and safety becomes more prominent. The telescopic arm also has flexible deformation during operation, which will cause vibration of the whole vehicle system. Therefore, in order to ensure safety, accuracy, and efficiency in the working process, it is necessary to accurately predict the dynamic characteristics of the telescopic boom load in the working process. Objective: The purpose of this study is to establish a rigid-flexible coupling dynamic model of the crane, which can accurately reflect the dynamic characteristics of the telescopic boom during its operation in the simulation test. Methods: In theory, this study analyzes the characteristics of a truck crane and simplifies it as a cantilever beam. Based on the Euler-Bernoulli beam theory, the vibration differential equation of the mobile masscantilever beam system is established. In the aspect of simulation, the three-dimensional modeling software Solidworks is used to establish the solid model of the truck telescopic boom, the finite element analysis software is used to establish the finite element model of the telescopic boom, and the modal neutral file is generated and imported into ADAMS to establish the dynamic model of the truck crane multi-level flexible telescopic boom. The dynamic simulation of the virtual prototype model of the truck telescopic boom crane is carried out in ADAMS software to obtain the dynamic characteristics of the key components of crane under specific working conditions. Results: The vibration differential equation derived in theory can be used to solve the dynamic response of the crane jib under specific conditions by MATLAB programming. In the aspect of simulation, the error fluctuation and its causes in the key components of the crane in the working state are analyzed, and the rationality of the virtual prototype model is verified. Finally, through the trajectory planning of the crane under typical working conditions, the purpose of stable control of the telescopic boom system of the truck crane is realized. Conclusion: The derived equation is universal for solving the vibration of crane jib in general cases. The rigid-flexible coupling model also provides a reference for the dynamic modeling, analysis, design, and manufacture of a multi-stage flexible telescopic boom. The findings of this study can provide a reference for related patent research and development.

Propeller thrust tower crane slewing mechanism model identification

Any study of the dynamics and control of mechanical systems is based on adequate mathematical models that contain the dynamic parameters of the system under study. Their evaluation, in particular for the tower crane boom system, is a particularly relevant scientific and practical problem, the solution of which will provide the basis for further calculations of the optimal modes of movement of the tower crane slewing mechanism. The research aims to determine the dynamic parameters of the installation (moment of inertia of the slewing mechanism J, torque of dry friction forces M0, driving torque coefficient K1) and to plan experimental studies. The experimental method, numerical optimization methods (in particular, the modified Rot-Ring-PSO method), and statistical methods were used to conduct the research. Based on the results of the experiments, the dynamic parameters of the mathematical model of the laboratory installation of the tower crane slewing mechanism with propeller thrust were identified. The criterion that evaluates the identification error of the parameters K1, M0, and J was formed and minimized using the Rot-Ring-PSO algorithm. Plots of the kinematic characteristics of the movement of the boom system in terms of the angle of rotation of the boom and the speed of rotation of the boom were constructed. When processing the experimental data, the dependence of the error values on the supply voltage of the propeller drive was revealed. The error in the boom rotation speed at the drive supply voltage of 90% (compared to the voltage variant of 40%) decreased by almost 15%, and the error in the boom rotation angle at the drive supply voltage of 90% (compared to the supply voltage variant of 40%) decreased by almost 3 times. The regularity has been confirmed that with an increase in the supply voltage, the error value of the system decreases. In the course of processing the experimental studies, the dynamic parameters of the installation were identified: K1=4.80‧10-8 V/(rpm)2, M0=34.519 Nm, J=24.21 kgm2. The obtained results will be used to optimise the plant’s motion modes, and the developed identification algorithm can be used for other similar problems

Optimization of the force mode of range change in an articulated boom system with a geared sector at a fixed mode of crane rotation

Variational calculus methods were used to optimize the boom system's flight change mode. For this, a variational problem is set, which includes the differential equations of motion of the jib system, the optimization criterion, and the boundary conditions of the movement when the departure and rotation of the crane are changed. The root-mean-square value of the drive torque of the flight change mechanism during the start-up process, which is an integral function, was chosen as the criterion for optimizing the movement mode of the boom system. The kinematic characteristics of the mechanism for changing the departure of the boom system from the state of rest to reaching the steady speed of the load, at the steady angular speed of the turning mechanism, were chosen as boundary conditions. Such boundary conditions eliminate fluctuations of the load on the flexible suspension after the end of the start-up process when the departure is changed
 As a result of the numerical solution of the given variational problem, graphical dependencies of the optimal kinematic, power and energy characteristics in the process of starting the flight change mechanism, with a fixed mode of rotation of the crane, were constructed. The obtained optimal mode of movement of the departure change mechanism eliminates load fluctuations on the flexible suspension and minimizes dynamic loads.

The movement mode optimization of the manipulator on the elastic base according to the criterion of the mean square value of the rate of change of the drive torque

It was established the presence of boom system oscillations in the process of changing the departure into previous studies of the optimization of the movement mode of the manipulator on an elastic base according to the criterion of the root mean square value of the driving moment of the drive. The purpose of the presented article is to solve the problem of reducing these fluctuations to a minimum. In this work, optimization was performed, where as a criterion for optimizing the motion mode of the boom system of the manipulator, it is proposed to use the root mean square value of the speed of change of the driving torque of the drive. Since this amount of power load is the main external factor of the occurrence of oscillations in the elements of the boom system of the manipulator. The driving torque of the drive was find from the dynamic equations of motion of the manipulator. The rate of change of the driving torque it was define as the time derivative of the driving torque expression by the drive. Such a criterion for optimizing the traffic mode is an integral functional. Its minimization it was carry out by methods of variational calculus.
 The results of the conducted research made it possible is significantly reduce the oscillations of the elements of the boom system of the manipulator on an elastic basis during the movement in comparison with the criterion of the root mean square moment. As result, to create a drive control system that allows to implement the obtained optimal mode of movement.

Comparative Study of the Influence of the System Architecture on the Accuracy of Hydraulic Cylinder Working Movements

The article presents the results of experiments aimed at finding the displacement of a cylinder being part of a boom system, as recorded after initiating a rapid breaking process. The tests were performed on a special test stand which allows modifications of the control system architecture. The article presents a comparative analysis of three systems different with respect to their architecture and use of control valves. It discusses the test results and the influence of the architecture of a hydrostatic system on the accuracy of the resultant position of the working element. The article also describes the influence of external loads on the working movement accuracy of the tested systems. The results allow the author to relate the structure of a hydraulic system to the parameter of the obtained working movement accuracy with respect to the maximum values of pressures and dynamic forces.

Energy and Operation Characteristics of Electric Excavator With Innovative Hydraulic-Electric Dual Power Drive Boom System

Energy and Operation Characteristics of Electric Excavator With Innovative Hydraulic-Electric Dual Power Drive Boom System

Analysis of the refined mathematical model of the manipulator boom system with an elastic base

This study was proposed a refined mathematical model of the boom system of the manipulator, which makes it possible to study the dynamics of the manipulator robot, taking into account the compliance of the elastic base due to its deformation. The mathematical model based on the Lagrange equations of the second kind for a mechanical system with two degrees of freedom, and the angle of rotation of the manipulator boom relative to the horizontal surface and the swing angle of the support frame was took as generalized coordinates. The purpose of this study was to analyze the behavior of the boom system of the manipulator on the effect of the drive torque from the hydraulic drive system and to obtain the kinematic characteristics of the generalized coordinates and amplitudes of oscillations of the compliant support link.

Instability load analysis of a telescopic boom for an all-terrain crane

Abstract. The instability load for the telescopic boom of an all-terrain crane is investigated in this paper. Combined with structural characteristics of the telescopic boom, each boom section is divided into several substructures, and the fixed-body coordinate system of each substructure is established based on the co-rotational method. A 3D Euler–Bernoulli eccentric beam element of the telescopic boom is derived. On the premise of considering the discretization of gravity and wind load, internal degrees of freedom of the substructure are condensed to the boundary nodes, forming a geometrical nonlinear super element. According to the nesting mode of the telescopic boom, a constraint way is established. The unstressed original length of the guy rope is calculated with a given preload so as to establish the equilibrium equations of the boom system with the external force of the guy rope and the corresponding tangent stiffness matrix. Regarding the above work, a new method for calculating the structural equilibrium path and instability load of telescopic boom structure is presented by solving the governing equations in a differential form. Finally, the method is validated by examples with different features.

Optimization of manipulator's motion mode on elastic base according to the criteria of the minimum central square value of drive torque

The results of studies of optimizing the mode of movement of the manipulator boom, mounted on an elastic base with a known stiffness the paper presents. The purpose of this scientific research is to reduce the oscillations of the manipulator turnout system, which will increase the overall efficiency of the manipulator, durability and reliability of the metal structure elements. The implementation of this goal have achieved by applying a controlled mode of operation of the drive with dynamic balancing of the drive mechanism. Using the Lagrange equation of the second kind, the equation of motion of the manipulator boom was compile and the expression for the generalized driving moment of the drive mechanism of the manipulator boom system was determined. This study considers only the angular displacement of the manipulator boom. The unbalanced drive driving moment of the manipulator boom had estimated by the component of the total inertial moment of the moving mass of the boom and load and the static load from the mass of the boom and load on the drive mechanism. The elastic base of the manipulator was present in the form of a linear spring with a given coefficient of elasticity. Since the main external factor of oscillation, perturbation in the metal structure of the manipulator is the driving moment of the drive, so we used the target optimization function, which estimates the root mean square value of the driving moment of the drive mechanism. The main criterion for optimizing the mode of motion was present in the form of an integral functional, and the search for its minimum value is carried out using the methods of calculus of variations.
 The results of this work can used by the drive control system at the design stage of the manipulator and during its operation. The dynamics of oscillations of such structural elements of boom systems of cranes is also estimated. The implementation of the obtained optimal modes of movement can be carried out using a hydraulic drive.

STORAGE AND COLLECTION RIVER DEBRIS PLANNING IN TANGGUL RIVER SURAKARTA CITY, INDONESIA AS SOURCE OF WASTE MANAGEMENT USING THE MULTI-CRITERIA DECISION-MAKING METHOD

The Tanggul River in Surakarta City is a tributary that empties into the Bengawan Solo River. Domestic activities located on river borders can pollute with the waste generation. Therefore, managing waste sources such as storage and collection is crucial in waste management. This study aims to analyze waste management from river debris storage and collection around the study site. The technique used in this research is direct observation of the study area and performing a decision analysis for alternative processing. Decision support system has one model, namely Multi-Criteria Decision Making for environmental development. The activities for collecting and sorting river debris in the Tanggul River are not yet available. The existing river debros collection used a 7 cm diameter net that has been installed at the sluice gate of the Tanggul River. Considering aspects or criteria in implementing accommodation activities needs to be carried out before determining the best alternative. Therefore, several measures need to be considered in determining the container based on SNI 19-2454-2002 concerning Operational Procedures for Urban Waste Management and Minister of Public Works Regulation Number 3 of 2013. The collection activity in alternative 1 uses the Brute Boom system: Heavy Duty Containment Boom equipped with a galvanized weir mesh net attached under the boom. The collection activity in alternative 2 uses a floating cube. The floating cube is a cube-shaped Waste holder that can float in the river to effectively hold waste floating on the surface of the river body. It is imperative to prevent river pollution from activities by providing infrastructure for storing and collecting waste. However, it does not have a more significant impact, such as the Tanggul River to the Bengawan Solo River in Surakarta City.

Motion characteristics and energy efficiency of potential energy recycling system of telescopic handler

Telescopic handler is combined of truck crane and forklift. Equipped with different accessories, the telescopic handler can achieve fork loading, lifting and other operations. Large amount of energy is needed to maintain lifting and lowering in large range with high frequency of the working device of telescopic handler. There is no energy recycling device for the working device that leads to the large dissipating of gravitational potential energy. In order to recycle the wasted energy, a three-chamber hydraulic cylinder boom system (TCCBS) is proposed. In this paper, the recycling principle is described. Then the energy consumption characteristics are analyzed. Further, the mode of TCCBS of telescopic handler is established and analyzed. Compared with the double chamber cylinder boom system (DCCBS), the single-action time of the boom is reduced 4.15 s. The velocity shock decrease from 0.12 m/s to 0.02 m/s at the beginning of the boom lowering process. The peak pressure decreased from 24 MPa to 21 MPa and the average pressure decreased from 17 MPa to 13 MPa during boom lifting process. The potential energy recycling of the working device is 139 kJ, which accounts for about 47.1 % of total potential energy. The cumulative output energy of TCCBS is 311 kJ, which is 92 kJ less than the DCCBS. The comprehensive energy saving efficiency is 22.3 %. The results show that the TCCBS can realize the potential energy recycling.

Implementation of optimal energy displacements of the working tool of the two-link manipulator along the parabolic trajectory

The intensive spread of automated and robotic systems in the construction industry poses a number of problematic and unsolved problems related to the efficiency and reliability of their use, namely: reducing dynamic loads in the structural elements of robots and manipulators, reducing energy costs to perform a given process by a robotic system. Particular attention is paid to the quality of control, in particular, in a limited working space when moving working bodies with hydraulically actuated manipulators, which are dominant in construction.
 Problems: For welding of metal structures or when laying building elements using handling systems, the technology for performing such work involves the use of the tasks of moving special working bodies along parabolic trajectories. To implement the tasks set by manipulators, it is necessary to determine the control laws for the drive system. One of the ways to find the necessary functions for the control system is the use of optimization problems according to energy criteria and imposed geometric restrictions.
 Purpose: to develop and investigate the modes of movement of the drive mechanism of a hydraulic manipulator with the implementation of an energy-intensive mode of operation of a mechanical system in a given space of movement of the working body along a hyperbolic trajectory.
 Methodology: To achieve the goals of the study, it is proposed to use the optimization problem of minimizing energy consumption in the boom system of a two-link manipulator on a given parabolic trajectory of movement of its working body in a limited working space. In this paper, we consider the problem of conditional optimization, where the restrictions of the working space are imposed by the conditions of movement of the working body and the limiting restrictions on the movement of actuators. The objective optimization function is formed in the form of Lagrange equations from the components of energy consumption and the equation of a parabola that specifies the movement of the manipulator grip.
 Results: To implement the optimal control of a two-link manipulator on a given parabolic trajectory, it is necessary to determine the extremals of the objective function functional in the form of the Lagrange equation for the components, which in this study were convolutions from the dependencies of energy consumption and the given equation for the trajectory of movement of the working body. The search for the minimum of the objective function is obtained in numerical form, based on which the form of the polynomial of the analytical dependence of the generalized coordinates on time is determined.
 Conclusions: In further research, it is desirable to consider criteria that take into account various force loads, in particular, the root-mean-square value of the drive force and the intensity of its change over time, and it is also necessary to develop polynomial functions that can be used to express numerical solutions to optimization problems.

A Study on a New Independent Metering Valve for Hydraulic Boom Excavator

Nowadays, hydraulic excavators are an indispensable part of the construction industry; however, conventional hydraulic excavators consume a great deal of fossil fuel and release a large amount of pollution emissions into the environment. This causes many unwanted costs, therefore, effective solutions are required to solve the above-mentioned problems. In this paper, a new independent metering system is proposed to improve energy-saving and reduce costs of a conventional system. In detail, a directional valve is used to control movement and three electro-hydraulic poppet valves are integrated to adjust the flow rate at the inlet and outlet ports of the boom cylinder. In addition, a control strategy based on the coordination between the speed of the pump and the opening area of the spool valve is designed to improve the performance of the system. Specifically, the valves are controlled based on the strategy that the meter-in valve is opened fully to reduce throttling losses and that the meter-out valve is controlled to reduce leakage. The speed of the pump is adjusted according to the feedback position signal. To demonstrate the effectiveness of the new configuration, a real test bench of the boom system was built under laboratory conditions. From the experimental results, the new independent metering valve system not only works with a high tracking precision, but it also reduces energy consumption. Compared with a conventional independent metering system, the fuel economy of the proposed structure can achieve a reduction of approximately 6.5%.

Asymptotic Tracking Control on Profiling Posture of Sprayer Boom Systems With Position Uncertainties

An adaptive and robust backstepping method based on wavelet network approximation was proposed to solve the problems of load variation, unmodeled uncertainties, physical parameter perturbation and external disturbance in the sprayer boom profiling system. Firstly, a complete mathematical model for the boom system with uncertainties, unknowns and nonlinear terms was established and transformed into a state space form with strict feedback. Secondly, the designed wavelet primitive was used to construct the neural network, to approximate the virtual equivalent control part of the backstepping method under the condition that the optimal error is bounded. The adaptive update law was selected to estimate the unknown parameters. The robust compensation term was introduced to reduce the adverse effect of the composite interference on the system. The input command signal order requirement was reduced. Finally, suitable functions were constructed by means of the Lyapunov stability theory, to prove that the position tracking error of the closed-loop system asymptotically converges to the origin. The simulation results show that, the proposed control method can realize the rapid maneuver adjustment of the sprayer boom position and posture, and effectively enhance the robust stability and control accuracy of the boom system.

ESO-based nonlinear flying boom attitude control with the handling qualities requirement

Attitude control is an important component of the flying boom system and plays a key role in air-to-air refuelling. A flying boom attitude control task is usually constituted by two subtasks. The first is to reject disturbances in the flight environment, and the second is to enhance handling qualities so that the flying boom can be efficiently and safely navigated into the refuelling receptacle by the boom operator. This paper presents a novel extended state observer (ESO)-based nonlinear flying boom attitude controller design method. To solve the first subtask, the ESO is introduced to estimate the disturbances and uncertainties of the flying boom. Based on the estimation, a nonlinear feedback controller is designed to reject the disturbances in real time. With the support of Lyapunov stability criteria, it is proved that the desired attitude trajectories can be bounded tracked by the flying boom under the proposed controller and the closed-loop dynamics of the system converge to a second-order reference model. To solve the second subtask, the parameters of the reference model are selected with desired handling qualities based on a handling qualities criterion of the flying boom. With the proposed controller, the flying boom system can have both high tracking performance and desired handling qualities. Comparisons among the proposed method and the related methods are simulated to reveal that the proposed method performs better in terms of tracking performance and robustness. Besides, a series of experiments are made on a simulator to validate that the proposed controller can achieve the desired handling qualities.