Telescopic Boom Research Articles

Multi-Objective Surrogate Modeling Through Transfer Learning for Telescopic Boom Forklift

Simulation and optimization methods have been widely used in forklift design due to their cost-effectiveness. However, this type of method involves challenges such as the accuracy of the simulation model and the simulation solution time. These challenges reduce the stability and precision of the surrogate model and hence generate further optimization errors. In this paper, a multi-objective surrogate modeling (MSM) method for telescopic boom forklifts based on closed-loop transfer learning is proposed in order to solve these challenges. The MSM consists of the following two steps: to pre-train an initial deep neural network model (deep model) with a large amount of existing simulation data from the same type of forklift and to transfer the model with a small amount of measurement data collected on the current forklift. A general framework for deep neural network (DNN) training is introduced to improve the approximation ability of the initial model. Moreover, a novel uncertainty-analysis-based sampling method is suggested for measurement data development, and combined with transfer learning to form a closed-loop mode to improve the stability of the final model. The superiority of MSM is demonstrated through comparative studies with the fine-tuning method on a telescopic boom forklift with two objectives. The experimental results show that the Correlation coefficient (R) of the deep model can reach 0.9971 by using only 80 sets of training data. In addition, it can also achieve an improvement of at least a 13.25% reduction in Root Mean Squared Error (RMSE) and a 9.19% reduction on average in Maximum Absolute Error (MAE), as well as stronger robustness compared to the benchmarks. Furthermore, it will provide a valuable reference for the simulation optimization of complex electromechanical products.

The use of serial automotive equipment when performing special lifting tasks

The solution to the problem of increasing the productivity of tow trucks and cranes on the chassis of serial cars largely depends on the solution to the issues of mastering the production of new types of heavy lifting capacity, the development and creation of progressive technological processes of maintenance and operation. Compared to a simple truck, vehicles equipped with a manipulator have a number of advantages: higher technical and economic indicators; the ability to vary the carrying capacity over a wider range; service by one driver of several transport units and others. The efficiency of using such units is mainly determined by the totality of their operational properties, which require rational management at the stages of design, production and operation. There are many types of lifting mechanisms for loading units, the most common of which are structures in the form of a telescopic boom and in the form of a combined loading device. The aim of this work is to create and parametrize the invariant structure of a telescopic boom in such a way that, when changing its parameters, it would be possible to obtain an arrow of any kind. The presented consideration shows that the use of such machines and assemblies is a wide area, in the study of which it is necessary to apply many branches of modern natural science and technology. There is no doubt that both the growth of research in this area and an increase in the volume of practical applications of objects of this type will continue.

Heave and horizontal displacement and anti-sway control of payload during ship-to-ship load transfer with an offshore crane on very rough sea conditions

Ship-to-ship load transfer with offshore cranes is challenging in rough sea conditions because of the difficulty in compensating for the increased position-velocity-acceleration errors and the restriction of the unloading area.This study proposes an efficient solution by integrating the combined vertical, horizontal, and anti-swing control system, experimentally validated mathematical hydraulic system and ship motions on irregular waves, the dynamic model of the crane, and an innovative control strategy. Particle Swarm Optimization-Proportional-Integrative-Derivate (PSO-PID) Trajectory Route Control System ensures safe unloading by advancing in the desired vertical position and speed route. The operation's horizontal positioning is realized even for very rough sea conditions with the support of the PID-controlled main and elbow boom. An extra added telescopic boom is used for anti-swing control with Particle Swarm Optimization Proportional-Derivative-Second Derivative (PSO-PDD2) control system.Simulations with different sea conditions were made and analyzed to verify the study's system model's effectiveness. The simulation results revealed that the system model is a valid and successful solution.

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.

Modelling and Analysis of the Positioning Accuracy in the Loading Systems of Mobile Cranes

In this work, the authors analyse the influence of the order and range of sequential movements of a crane's working members on the accuracy of the final cargo positioning. The analysis was conducted on the basis of a specially developed method in which the authors proposed the introduction of a geometrical indicator of positioning the load in the intermediate positions (after completing each movement sequence) and in the target position, depending on the adopted control strategy and the accuracy of kinematic input of the working mechanisms (powered mechanisms). A mathematical model was presented to enable the accuracy of unidirectional positioning of the crane's working members when conducting sequential movements controlled through the rotation of the crane column, inner and outer boom, and retractable stages of the six-section telescopic boom. Sample results of the numerical simulations showing the influence of the assumed kinematic inputs of the crane members on the accuracy of unidirectional angular and linear positioning and, consequently, on the accuracy of the final positioning of the transported cargo, were presented. Moreover, an indicator of the cargo positioning accuracy dependent on the location of an operator or a video camera and the trajectory of the cargo was developed, allowing the formulation of application conclusions.

Telescopic handlers: applications, challenges and scope

Telescopic Handlers, also known as Telehandlers or teleporters or boom lifts are small human-operated machines extensively used by the agricultural, construction and landscaping industries. Different types of attachments are being used with these telehandlers which make them extremely versatile, safe, swift and costumer friendly. They prove out to be very efficient when used with various attachments designed as per the market requirements. Common attachments include forks, lifting jibs, man-basket or work platforms, buckets etc which are attached to the telescopic boom of the telehandlers as per use. However, these attachments should be chosen with utmost care keeping in mind that it does not pose any threat on the operation safety. While, these telehandlers have numerous advantages and applications, they also have certain limitations which slightly restricts their use in some cases. The present work is a review on telescopic handlers, their applications, limitations and future scope of research on their improvement to expand the domain of the usage.

A Measurement-Aided Control System for Stabilization of the Real-Life Stewart Platform.

In the paper, an innovative control system devoted to the stabilization of the parallel manipulator-type Hexapod is presented. The device consists of three main parts, allowing us to reach the desired location during various external disturbances. Indeed, the telescopic boom located on the car along with the system providing the correction of the boom column deflection as well as the gyroscopic self-leveling head constitute a complex tool covering a plethora of modern techniques and solutions. Through the application of advanced issues strictly derived from nonlinear identification and multivariable control theory branches, the dynamical behavior of the discussed device has been handled in order to achieve a proper reference operation. Naturally, it has been supported by a set of accompanying approaches related to the processes of the real-time measurement and robust data transmission. It should be emphasized that the proposed computer-aided system is intended for the film industry, where image stabilization plays a crucial role. Such a statement has additionally been confirmed by other innovative products introduced by a company placed in Opole, Poland, called MovieBird International.

Load validity discrimination for telescopic boom of rock drilling jumbo

The telescopic boom is an essential component in the rock drilling jumbo. To avoid the influence of the invalid load schemes on optimization design, it is urgent to find a method that can efficiently discriminate the validity of load schemes. Based on the combination of Classroom-like Generative Adversarial Network (CLGAN) and Conditional Generative Adversarial Network (CGAN), Conditional Classroom-like Generative Adversarial Network (CCLGAN) is proposed in this paper to discriminate the validity of load schemes. And comparative experiments are designed to compare the effects of different training strategies, loss functions, and discriminators with different structures on the discrimination ability of discriminators. The comparison results show that the improved training strategy, Wasserstein loss, and the discriminator with 2 output nodes have better performance. The optimal CCLGAN is trained to discriminate the load schemes, and the discriminator in the optimal CCLGAN including 5 different types of generators has the best discrimination performance.

Neural fractional-order control of telescopic truck cranes

A telescopic boom crane is a strictly underactuated system in which three actuators track five motions. The boom luffing and extension cause variations in the shape and structure of cranes. The dynamic reaction between payload and boom through a flexible rope and viscoelastic cylinders induces significant vibrations. Additionally, a crane contains many uncertain parameters, suffers wind disturbances and sometime encounters failure of actuators. On the basis of a complex model with five fully nonlinear differential equations, we construct an intelligent robust control system for such cranes, which integrates the benefits of advanced techniques. Fractional-order control combined with robust control produces a controller holding flexible derivative orders. A multilayer perceptron network provides a learning feature to the cranes, in which an adaptive mechanism estimates one equivalent component represented for individual influences. Simulation for a practical crane shows the effectiveness of the proposed control system.

Modeling and observer-based robust controllers for telescopic truck cranes

Strict underactuation, complex structure, shape variation, and elasticity of machine elements cause many challenges in control of telescopic truck cranes. We develop a dynamic model of telescopic boom cranes considering flexibility and damping of load-carrying rope, viscoelasticity of boom-luff cylinder and extension cylinder. Modeling and control are constituted for the complex operation in which three motors including payload hoist, boom elevation, and boom expansion are simultaneously activated. We provide two observer-based robust controllers entitled second-order and fast-terminal sliding mode controls. These controllers work well even when the crane faces parametric variation and disturbance. The control system halves its sensors because of the performance of observer. We analyze and verify the effectiveness of modeling and controllers by applying to a Grove-TMS500 truck crane. Simulation results show the asymptotical convergence of actuated outputs and the stabilization of unactuated ones. The crane responses hold the robustness against winds and parametric uncertainties. The oscillations of crane outputs are due to elastic components such as handling ropes, two hydraulic cylinders for luffing and expanding the boom. The controllers well eliminate these undesirable oscillations.

DYNAMIC MODEL OF A RAILWAY LIFTING CRANE

Introduction: Currently, mobile boom cranes equipped with telescopic boom equipment are widely used in construction, loading and unloading, as well as installation. Purpose of the study: We aimed to develop a dynamic model for a railway lifting crane, taking into account the interaction of its structural elements with each other and the bearing soil surface in a three-dimensional formulation. Methods: In the course of the study, we used Simulation and Motion modules of the SolidWorks software package, Klepikov’s non-linearly deformable soil model, and Lagrange’s equation of the second kind. Results: As a result, we developed a numerical analytical 3D model describing dynamic loading and deformation of the “mobile boom crane – foundation” system in a three-dimensional formulation. The model takes into account the following: the internal bending deformation and the interaction of the mating structural elements of a crane (telescopic sections, telescoping hydraulic cylinders, and outriggers), hoist rope rigidity, grillage (framework of sleepers) influence, elastic and plastic properties of the base platform soil, and action of inertial loads on the structural elements of the lifting crane.

Heading set of equipment for underground development galleries drivage in rocks prone to gas-dynamic phenomena

The article presents the design of the heading set of equipment for drivage of development galleries in rocks prone to gas-dynamic phenomena. This equipment can carry out the full technological cycle of rock excavation. The use of the P-110 roadheader of Ukrainian PJSC “Novokramatorskyi Machine Building Plant” with an operating device on a telescopic boom is offered for the aggregation of the heading set of equipment for underground development galleries drivage in emission-hazardous rocks. The device for mechanized boreholes drilling in an emission-hazardous coal seam has been devised based on the EBGP-1 M drilling machine of the Ukrainian SPA “Chervonyi Metalist Co Ltd”. This device is placed on the telescopic boom of the roadheader. For mechanized drilling of explosive, degassing, unloading and injection boreholes, a rock-breaking tool has been proposed that can perform an effective vibratory and rotary loading method of drilling in medium-hard and hard rocks. Safe methods for underground development galleries drivage in gas-bearing emissionhazardous rocks have been worked out. The effectiveness of these methods was determined in industrial conditions. It is possible to conclude that this new heading set of equipment and technology can be recommended for implementation in the mining coal industry.

Development of Extended Super Dragon Articulated Robot Arm with a Linear Telescopic Boom

Development of Extended Super Dragon Articulated Robot Arm with a Linear Telescopic Boom

The inertial loads of a telescopic boom of a truck crane

Problem. The analysis of existing research and publications in which the main problem is highlighted, namely, that many factors are not taken into account when calculating the inertial loads of the car crane arrows. Accounting for these factors will allow you to more accurately determine the inertial loads of the boom of the car crane, to carry out strength-hunches of the elements of the boom and the selection of components of its drive mechanisms. Goal. The purpose of the work is to determine the inertial navan-loads acting on the load and arrow of the automobile-side crane during the unstable movement of its. Methodology. To calculate the inertial loads, the technique of determining the total inertial loads of the car crane boom during joint operations in accordance with the Safety Regulations has been developed. Total inertial loads were determined for the following cases: joint lifting (lowering) of cargo and arrows; lifting the load and turning the boom; lifting and turning the arrow. Results. The resulting dependencies for determining the inertial loads of the rotary boom of the car crane will allow more accurately taking into account multiple factors to calculate the values of these loads in order to conduct strong calculations of the boom, the selection of its components mechanisms. Originality. When calculating inertial loads, the weight and length of the boom are taken into account; weight and height of lifting of cargo; the radius of the arrow crane; rotation speed of the rotary part of the crane; speed of movement of cargo and arrows; start time and braking of cargo lifting mechanisms, change of departure and turn of the boom. The advantage of this technique is its originality. Practical value. The use of this technique allows more accurately taking into account multiple factors to determine the values of the inertial loads of the automobile crane during the unstable movement of the cargo lifting mechanisms, changes in the discharge of the boom and its rotation in order to conduct strong-standing calculations of the boom elements, the selection of its components.

Lateral vibration behaviors of the straight boom of the aerial work platform in the horizontal linear motion

Comparing to the scaffolding on building construction, Aerial work platforms (AWP) can transport human and materials to the working height quickly and conveniently. However, the sender boom of the AWP is vulnerable to elastic vibration due to the limited stiffness. This paper proposes an accurate dynamic modeling of the AWP in the linear motion, which takes telescopic and luffing movements into consideration simultaneously. Considering the influence of the luffing hydraulic cylinder and the overlap of boom sections, the cylinder is regarded as the elasticity support, and the telescopic boom is divided into a limited number of boom parts. Then, the Hamilton's principle is utilized to establish the governing equations of the motion of each boom part, which will be discretized in time domain. The transient vibration characteristics is calculated based on the modal superposition. Subsequently, their functions with respect to boom length are obtained through polynomial fitting method to approximate the mode shape of entire boom. Based on the modal parameters, the Galerkin method is employed to truncate the first two order modes to establish dynamic model and transform it into the state space form. Finally, an actual example of AWP is performed in Matlab/Simulink to obtain the vibration response of the boom tip to validate the proposed method. With the comparison of the model ignoring the influence of the elasticity support and the overlap, the results can be obtained to indicate that these simplifications can bring amplitude deviation. The dynamic modeling presented in this paper can provide a theoretical reference for the active vibration damping control of the AWP in the linear trajectory movement.

The Impact of Temporary Means of Access on Buildings Envelope’s Maintenance Costs

Accessibility to buildings’ envelope depends on efficient inspection and other maintenance actions of their components. When access to these components is not planned, special means of access are required to carry out the maintenance work. Means of access, besides having a fundamental role on the quality of maintenance works of building envelope components, also represents a considerable part of the maintenance costs. Thus, to optimize costs and resources in maintenance plans, assessment of the impact of the means of access on maintenance costs is crucial. For works in height, there are several alternative means of access. The choice of the most adequate solution is strongly linked to the characteristics (e.g., architecture, height) and constraints (e.g., users, surrounding space) of each building, the maintenance needs of the envelope, and the time and funds available for the intervention. Therefore, in this study, a sensitivity analysis to understand how the cost of means of access can influence the maintenance costs is carried out. Moreover, the optimisation of maintenance activities in façade claddings is also analysed. This study intends to assess whether it is advantageous to consider permanent means of access during the design phase or opt for temporary means of access. In a first stage, the impact of six temporary means of access (supported and suspended scaffolds; articulated booms; telescopic booms; scissor lifts; and rope access) on the maintenance plans developed for the six types of claddings (ceramic tiling systems—CTS, natural stone claddings—NSC, rendered façades—RF, painted surfaces—PS, external thermal insulation composite systems—ETICS, and architectural concrete façades—ACF) is examined. The impact is estimated through a stochastic maintenance model based on Petri nets. After that, a sensitivity analysis and a multi-criteria decision analysis are performed. Based on the results, general recommendations are presented concerning the maintenance strategies to adopt in the cladding solutions analysed. The results reveal that planning the means of access during the design stage can be economically beneficial for all buildings’ envelope components.

РАСЧЕТ И МОДЕЛИРОВАНИЕ КАНАТНОГО МЕХАНИЗМА ТЕЛЕСКОПИЧЕСКОЙ СТРЕЛЫ МОБИЛЬНОГО КРАНА

Power analysis and computer modeling of moving the telescopic boom rope mechanism using the “Universal Mechanism” software package, considering the mechanical characteristics of the ropes, boom sections and their contact interaction, have been carried out. The dependences for calculating the preliminary tension of the ropes are obtained, the regularities of operating the cable mechanism of the crane telescopic boom are established.

Coupling a differential global navigation satellite system to a cut-to-length harvester operating system enables precise positioning of harvested trees

ABSTRACT Cut-to-length harvesters collect detailed information on the dimensions and characteristics of individual harvested trees. When equipped with global navigation satellite system (GNSS) receivers and motion sensors, the obtained measurements can be linked to locations of single harvested trees, benefitting a range of forest inventory applications. We propose a way of georeferencing harvested trees using a Komatsu 931XC harvester, which measures and records the machine's bearing, crane angle and crane length for each harvested tree. We replaced the harvester’s standard GNSS receiver with a dual-antenna differential GNSS receiver. From the coordinates obtained, rotations calculated from the GNSS receiver and data on crane length, we determined the location of 285 trees harvested in eight final fellings in Norway. We compared the obtained locations to control measurements taken on the corresponding stumps directly after harvest using a differential GNSS receiver. The mean distance between planimetric coordinates of trees measured by the harvester and corresponding control measurements was 0.88 m with a standard deviation of 0.38 m. By correcting the crane lengths for systematic deviations between harvester and control locations, the mean distance was reduced to 0.79 m. This study shows that measurements of single harvested trees can be georeferenced with sub-meter accuracy, by mounting a differential GNSS receiver on a harvester and without installing additional sensors. The results also suggest that the positional accuracy can be further improved by measuring and recording the length of the telescopic boom, and that with minor adjustments, the system could be fully automated.

Analytical method for the out-of-plane buckling of the telescopic boom with guy cables.

The guy cables can effectively improve the bearing capacity for the telescopic boom of the crane, while the introduction of tensioned cables makes the buckling analysis complicated. The primary objective of this study was to propose an analytical method for the out-of-plane buckling of the telescopic boom with the spatial symmetric guy cables. To analyze the influence of the guy cables on the out-of-plane buckling property of the telescopic boom, the deflection differential equation of the multi-stepped telescopic boom with guy cables was established based on the theory of elastic beam, then the buckling characteristic equation to determine the critical load of the telescopic boom was derived. Comparison of results with that given by the finite element method showed the high accuracy of the proposed method. In the end, with this equation, the influences of the structural geometric parameters on the critical load were investigated. The results indicated that, in the engineering application, the critical load of the telescopic boom can be increased by decreasing the length ratio a/L or increasing the angle φ between the two cables. The influence of angle θ on the out-of-plane buckling analysis of the telescopic boom can be neglected. With the proposed method, the buckling behavior of the telescopic boom with guy cables can be solved accurately. The present work is significant to structural design and safety analysis of the telescopic boom, and it can be utilized to provide technical support for the structural design of telescopic boom.

Overall stability analysis of combined boom with telescopic main boom and fixed flying jib

On the purpose of accurately analyze the overall stability of the combined boom, and it also provides calculation basis for the structural design of the crane combined boom and the revision of the Chinese Design Rules for Cranes GB3811-2008. In order to analyse the overall stability of the combined boom accurately, the deflection differential equations of combined boom is established based on the vertical and horizontal bending theory. What’s more, combining the constraint and displacement boundary condition, the precise recursive expression of the buckling characteristic equations of the combined boom is derived. Taking the combined boom of 6-section telescopic main boom and fixed flying jib as an example, the proposed method and the ANSYS simulation method are used to calculate the critical bucking force of the combined boom, and the comparison results show that: the deduced instability characteristic equation of the combined boom is correct and accurate, which is necessary to the designing analysis in engineering.