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Epicyclic gears also known as Planetary Gears is a system which consists of planet gears, a sun gear, and a ring gear. The Sun gear is mounted and rotated about the centre and meshed with planet gears which are connected with the help of a carrier. These planet gears are meshed with ring gear. This type of gear has a wide range of application in wrist watches, automobiles, and hoist. This paper focus on epicyclic gear In Wind Turbine. Necessary calculation for design is done and the Gear System is modelled in Solidworks. Analysis of the gear system carried out through Ansys. Simulation for total deformation, von-Mises stress, Shear stress for two cases for two different materials. Finally results were concluded on the best material.

The hoist is an important equipment in the mine pit. Since the containers are lifted or lowered with flexible steel wire ropes, there are shocks and vibrations during operation, especially in the emergency braking stage, the shocks and vibration will be more severe. Mine hoist is a complex system; therefore, it is difficult to obtain all its dynamics information only by investigating the flexible hoisting subsystem or hydraulic brake subsystem. Therefore, it is very necessary to establish an accurate model to predict these characteristics of the hoist, this will provide useful tools for hoist design and maintenance. Therefore, a joint modeling methodology is proposed and implemented in this paper. A hoisting system model considering the non-linear factors such as contact characteristics and flexibility was established in RecurDyn. The hydraulic braking system model and control system model were established in AMESim, and the co-simulation model was constructed by the interface module. In this co-simulation model, not only the flexible hoisting subsystem and hydraulic brake subsystem are included, but also the coupling effect of subsystems is considered. Finally, taking the lifting condition as an example, execute emergency braking research on the hoisting system under experiment, mathematical model, and co-simulation model, respectively. Comparing the co-simulation model with the mathematical dynamics model, and the experimental test results, research indicates that the joint simulation model of coupled hoisting system and hydraulic braking system can effectively reflect the dynamic characteristics of the actual hoisting system. It provides an effective tool for hoist design, optimization, performance analysis, and operating condition simulation. In addition, the methods and techniques used in the co-simulation modeling procedure are portable. Therefore, the paper is of significance for the mine hoist.

Quadcopters typically suspend large-size loads by dual-hoist mechanisms for material-handling services. The dual-hoist dynamics exhibit complex coupling effects between the quadcopter attitude and distributed-mass loads. Therefore, manipulation is a challenging task due to the dual-hoist dynamics. Some progress has been focused on single-hoist dynamics of quadcopters slung loads. However, little attention has been directed at dual-hoist dynamics. A planar dual-hoist dynamic model in near-hover operation can be noted in this article, and simultaneously used to design an oscillation-control method so as to facilitate flying such aerial cranes. Technological achievements presented in simulations exhibit the dynamic behavior of the analytical model and demonstrate that the control method succeeded in restraining the quadcopter attitude and load oscillations. The theoretical findings in this article might extend to other types of aerial cranes, such as helicopters or tiltrotors slung loads.

In modular steel building (MSB), connection is a critical part in the structural behavior and ability of load transferring. Previous MSB joints mainly use inter-connection plate or plug-in device, which ignore practical difficulties to hoist and install the modular unit. Therefore, this paper proposed an innovative corner-fitting connection, which is fully prefabricated and liftable. The seismic performance of the novel connection was analyzed by using finite element (FE) software ABAQUS. Numerical study of the novel joint was based on Simplified FE model and Detailed FE model. The developed FE model was verified by comparing with the test results of innovative connections in the previous references. The Simplified model for the joint was developed by using springs to connect the components. Five quasi-static cyclic loading FE analysis were performed on the innovative MSB connection to explore its load transferring capacity and seismic behavior. Results showed that weakening at the beam end can transfer the plastic hinge to the weakened position with little effect on the overall strength. The developed Simplified model can accurately predict the load–displacement curve and Von-mises stress of the joint. With these results, the cyclic response can be incorporated into the Simplified global model by defining the stiffness and dashpot coefficient of the spring. This paper proposed an engineering practical joint and Simplified FE model for seismic analysis of MSB, which is useful for the rapid development of this promising construction method.

Large charging cranes are used to introduce hot metal into the basic oxygen furnace through the use of induction motor drives for the main and auxiliary hoist. These motor drives shall have the capability of dealing with bidirectional power flow due to the action of lifting (motoring) or lowering (regenerating) the load. The use of the active rectifier increases the energy efficiency since the braking energy is not lost in heat. This article proposes a true unit power factor converter with a common dc bus and compares it to an existent solution. Theoretical analysis, simulation results, and losses calculation show the advantages of the proposal in terms of power quality, energy efficiency, and reliability. Hardware-in-the-loop results show the proper work of the developed control system.

This paper proposes an image-based visual servo (IBVS) control system for hoist positioning under the condition of heavy loading. Various advanced visual servo methods for positioning have been proposed. However, the visual servo scheme under heavy load condition remains the following problems: 1) The deformation and oscillation of the end-effector under the condition of heavy loading will lead to coordinate deviation of end-effector and visual frame, which makes the system unstable and brings more errors. 2) The vibration velocity and offset caused by deformation and oscillation are difficult to measure and model. To address these concerns, we first model the system error based on visual error and differentiate it. We obtain that the basic vector of the system error derivative contains the vector of vibration velocity, then we use the basic vector of derivative of the system error to build up the relationship between system error and vibration velocity. Moreover, we construct a double parallel feed forward neural network to estimate the basic vectors which contain vibration velocity and offset, and compensate for them. Also, we give the proof of the boundedness of the parameters based on Lyapunov theory. Simulation results depict the superior performance of the proposed method against the other advanced visual servo methods under the condition of heavy loading. Furthermore, experiments are conducted on the hoisting platform in our laboratory, which verifies the effectiveness of the proposed method.

Virtual reality (VR) simulation training for helicopter search and rescues (SAR) hoist operators is very uncommon in comparison to the availability of pilot simulation training. SAR hoist operators...

The brake system of a mine hoist is the key component and the last barrier to ensure the safe operation in a mine. Based on the vibration and the sound signals of a test brake system, this paper st...

Spindle devices, which are among the core components of mine hoists, are typical rotor-bearing systems. Vibration-based fault diagnosis techniques are often used to help prevent mechanical failures of such systems. The fault vibration signals generally include pulse information reflecting fault type, independent vibration components caused by other non-faulty mechanical components, noise in the surrounding environment and so on. The reduction of noise in the vibration signal collected by the sensor is of practical significance for the correct diagnosis of subsequent rotating machinery faults. To solve this problem, a fault diagnosis method based on a smooth (SM) filtering algorithm combined with variational mode decomposition (VMD) and a support vector machine (SVM) is proposed. Wavelet transform (WT) and wavelet packet transform (WPT) methods are used to compare the noise reduction. The reliability and effectiveness of the method are verified by experiments on a hoist mechanical fault simulator. Experimental results show that the proposed method has high prediction accuracy and can provide a good practical reference for fault diagnosis of rotating machinery.

Cranes play an important role in the industry sectors worldwide, such as construction, transport, shipping and cargo industry. For the safety of loading and unloading materials there are definitely ongoing improvements in the crane industry. However, there still remains issues related to the crane operation and control measures given by the pendulum swing while the crane is moving. To solve this problem a vision-based movement control of a 3 degrees of freedom (3 DOF) crane system, using both an analytical and experimental models based on displacements and adaptive optimization algorithms was proposed. The framework consists of three steps, more precise recognition, detection and tracking a set of targets within the image to compute the payload displacement. A prepossessing process was applied in order to enhance the image improving both the color information and the edge extraction task. Then, a set of targets within the image were detected to estimate the displacement. Then to solve the problem given by the displacement, a tracking task was implemented using a second order filter. This paper introduces a new strategy to determine the relationship between the movement of the spin in the jib and position of the markers within the image. Regression analysis was carried out to take into account the motion of the cart and the payload. In Results Section is shown a set of real-time experiment, obtaining euclidean errors of 1.41 pixel, 2 pixels and 3.16 pixels for Cart, Jib and Hoist, respectively.

A winding hoist is a key equipment for ultra-deep mine hoisting. The inter-circle transition in the winding process of the hoisting wire rope causes vibration, impact, extrusion, wear, and other negative phenomena, which seriously affect the service life of the rope. In order to explore the effect of inter-circle transition on the friction and wear performance of wire ropes, the present study adopts the principle of equal ratio scaling to build a test rig for an inter-circle transition of wire ropes, and the evolutions of coefficient of friction and maximum friction temperature with increasing the tensioning force and rope speed under dry friction were investigated by the test rig, and the major wear mechanisms under different working conditions were investigated in combination with the wear morphologies. The results show that the coefficient of friction decreases first and then increases with an increase in the tensioning force, and decreases linearly with increasing the rope speed. The evolution of maximum temperature over time under different tensioning forces and rope speeds are all mainly divided into three stages: The rapid growth phase, the slow growth phase, and the stable phase. The influence of the rope speed on the temperature of the wire rope is greater than that of the tensioning force. Moreover, in the process of inter-circle transition, the major wear mechanism is abrasive wear. Furthermore, larger tensioning force and rope speed may cause the steel wires on the contact surface of the wire rope to break.

We propose to use information regarding the fab's future state for Overhead Hoist Transport (OHT) dispatching, which is named as ‘predictive dispatching’ in this paper. Unlike conventional dispatch...

Internet of Things is an budding focus of technical, social, and economical importance. At the same time, Internet of Things hoist momentous challenges that may perhaps plunk in the way of apprehend its prospective reimbursement. The ‘thing’ in IoT may perhaps be a person with a heart monitor or an automobile in the midst of built-in-sensors, i.e. objects that have subsist dole out an IP address and encompass the capability to accumulate and convey data over a network without manual assistance or intervention. The business processes hosted on the wide-spread geographical distribution of sensors should retort to dissimilar sensing events congregate in the dynamic IoT environment as swift as they could. So to Produce better IoT applications, process optimization is indispensable in the IoT environment. For example, data analytics in energy embarrassed IoT Networks uses Optimization Framework to recuperate the network implementation delay and accuracy. Here we imply firefly Optimization Algorithm Framework, wherever the nodes make a decision where their data analytic tasks will be executed, in order to jointly optimize their average execution delay and accuracy, while respecting power consumption constraints compared to previous other techniques. Our new fire fly optimization techniques shows 81% better results compared to previous techniques such as Genetic and ant colony etc…

Tower crane systems exhibit high nonlinearity and underactuation, making the control issue challenging. Most reported methods for tower crane systems utilize linearized models, and accurate plant parameters (e.g., cargo mass, jib moment inertia) and full state feedback are usually required; moreover, most existing works only consider a part of the crane motions, and the control issue of five degree-of-freedom (5-DOF) tower cranes (i.e., 2-DOF cargo swing, slew, hoisting, and translation) is still open. However, tower cranes are practically influenced by uncertainties and disturbances, which may make linearized models ineffective; additionally, exact values of plant parameters may be difficult to obtain, and velocity signals are usually not directly measurable in practice. To address the aforementioned problems, this article proposes an adaptive output feedback control method for 5-DOF varying-cable-length tower cranes. As far as we know, this article provides the first adaptive output feedback controller, designed and analyzed without linearizing the dynamic equations, which can simultaneously achieve cargo hoisting/lowering, jib slew, trolley translation, and swing suppression, by avoiding using velocity-related feedback signals. Resorting to an elaborately constructed virtual spring-mass system, the control objectives are satisfactorily achieved even without involving any velocity signals with theoretical/experimental guarantee. Moreover, by elaborately designing a new adaptive law, the exact values of unknown cargo masses can be estimated through online identification. We provide rigorous stability/convergence analysis for the closed-loop system. Hardware experiment results are included for effectiveness/robustness verification.

Due to the recent advances in manufacturing systems, the semiconductor FABs have become larger, and thus, more overhead hoist transporters (OHTs) need to be operated. In this article, we propose a ...

For a crane system, when the payload is too large to be seen as a mass point, or the hook mass cannot be directly ignored, it performs more like a double-pendulum crane system, instead of a single-pendulum crane system. Due to many factors, the working environment of the industrial crane system is complex. Obstacles sometimes appear in the movement path of the payload, which affects the normal operation of the crane system and may cause accidents like collisions. To handle this issue, we propose a time optimal trajectory planning method for the double-pendulum crane system with obstacle avoidance, which ensures the objective of obstacle avoidance by the payload hoisting/lowering. During the trajectory planning process, a series of physical constraints, including the trolley velocity constraints, the trolley acceleration constraints, the payload's swing angle constraints and the hook's swing angle constraints are considered. It can improve the safety of the crane system during the entire working process and the transportation efficiency is also improved at the same time. Finally, the effectiveness of the proposed method is verified by simulations.

High strength polymer fibres are opening new fields in regard on their strength to weight ratio. In 2009 Liebherr and Teufelberger started a development partnership to utilise these opportunities and rethink the basics of hoist ropes for cranes: (1) Introduction; (2) The high strength fibre rope soLITE; (3) Load bearing capacity of the rope; (4) Liebherr fibre crane series; (5) Discard criteria.

Human errors are commonplace among hoist drivers in the hoisting task of coalmines. To reduce these errors and prevent accidents, it is necessary to identify the features of cognitive behaviors and main cognitive errors of the hoist drivers. This paper analyzes the accident cases and operating flow of coalmine hoist, and establishes a cognitive process model of coalmine hoist drivers. Further, the cognitive behaviors and functions of the drivers were analyzed stage by stage, revealing the distributions of their main cognitive behaviors and functions. It is learned that most coalmine hoist accidents concentrate in two stages: lifting, and operation monitoring. The operating processes in the two stages were further deliberated. The specific operations were extracted as the influencing factors of human errors, and the importance of each index was calculated through analytic hierarchy process (AHP). The research results provide a theoretical reference for identifying the key factors affecting the human errors of the operations by coalmine hoist drivers, and shed new light on how to prevent such errors.

The intubated and ventilated patient in austere and inaccessible environments requiring helicopter hoist extraction presents significant procedural and logistical challenges. This case report describes the use of a mechanical ventilator and visible advanced monitoring throughout the entirety of the patient journey from the prehospital scene to the hospital, including the period during hoist extraction as human external cargo.

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at their coordinated control for the purpose of establishing a fully-automated mechatronic system suitable for borehole drilling applications. Both the drill-string rotary drive and the draw-works hoist drive are equipped with proportional-integral (PI) speed controllers, which are readily available within modern controlled electrical drives. Moreover, the rotary speed control system is equipped with torsional active damping system and drill-string back-spinning prevention scheme for the case of stuck drill-bit scenario, whereas the draw-works-based drill-bit normal force control system is extended with the auxiliary control system aimed at timely prevention of the drill-string torsional overload. The design of proposed control systems has been based on suitable reduced-order control-oriented process models and a practical tuning methodology based on the damping optimum criterion aimed at achieving the desired level of closed-loop system damping. The functionality of the proposed cross-axis control system has been systematically verified, first by experimental tests of individual rotary/vertical axis control systems on a downscaled laboratory experimental setup, followed by thorough simulation study of the overall control system for realistic scenarios encountered in the field.

Quayside container crane is a type of crane that is placed on the dock at a container terminal that handles loading and unloading of containers from ship to dock or from dock to ship. Quayside container crane is composed of structural parts, mechanical components, electrical components and control systems. This research was conducted to find the root of the problem in the Quayside container crane, by analyzing the system that was experiencing breakdown maintenance. The data used was a breakdown history Quayside container crane No. 01 in 2018-2019 at the Patchouli Terminal of Tanjung Perak Port. The analysis methods used are Fault Tree Analysis (FTA) and Failure Mode and Effect Analysis (FMEA). From the results of the analysis carried out, it was found that a list of failures that caused the breakdown in 2018-2019 consisted of supply electrical power systems, main hoisting systems, spreader systems, gantry traveling systems, maintrolley traveling systems, and boom hoisting systems. The solution to reduce breakdowns that have occurred is by implementation of predictive maintenance, preventive maintenance, and repair of SOPs and annual maintenance contracts. By using quantitative analysis using Failure Mode and Effect Analysis (FMEA), the largest Risk Priority Number (RPN) is obtained on the main trolley travel system of 450, then continued by the gantry traveling system. 360, the main hoisting system is 280, the suplying electrical power system is 294 and the boom hoist system is 42. Based on the results of the Pareto diagram, the cumulative percentage of priority breakdown calculations is 83% of the main trolley travel system damage

Hoisting equipment is core to many industrial systems and, therefore, their state of health significantly affects production lines and personnel safety; this is especially important in environments such as coal mines. The health of the hoisting system can be estimated by deploying energy harvesting wireless sensor nodes that monitor the drum surface stress. In this network of sensor devices, it is very costly to send highly sampled data as it causes radio congestion and consumes energy. However, from our experience of sensing hoist systems, we note that the data observed at the upper surface of the hoist are significantly more indicative of the state of health of the whole system, compared with data sensed at the lower surface. Therefore, we need to take advantage of this to optimize the communications of sensor nodes. However, scarce energy can be collected for these devices from the hoist itself, along with the prioritized Quality of Service (QoS) requirements (throughput, delay) of monitoring signals, raises important challenges for energy management. In this article, we use Lyapunov optimization techniques and propose an energy-neutral and QoS-aware protocol (EQP), including duty cycling and network scheduling to solve it. Extensive simulations show that the EQP helps sensor nodes realize consecutive monitoring, and achieve more than 38% utility gain compared with existing strategies.

Актуальность исследования обусловлена необходимостью выявления причин выхода из строя узлов и деталей преобразователя частоты, а также конденсатора фильтрокомпенсирующего устройства в системе электропривода скиповой подъемной установки. Выход из строя этого узла при отработке алгоритма защиты приводит к наложению предохранительного тормоза на подъемную машину, обладающую достаточно большой кинетической энергией, которая в свою очередь, рассеиваясь в узлах и деталях подъемной машины, приводит к сокращению их срока службы. Цель: определить степень влияния высших гармоник в системе электроснабжения подземного рудника на элементы преобразователя частоты системы электропривода скиповой подъемной установки и предложить методы по их снижению. Объекты: преобразователь частоты, система электропривода подъемной установки, система электроснабжения подземного рудника, другие технологические установки и их системы электропривода, влияющие на генерацию высших гармоник. Методы: инструментальный контроль показателей качества электрической энергии в соответствии с требованиями ГОСТ 32144-2013; математическая обработка и анализ полученных результатов при помощи программного обеспечения MathCAD; компьютерное моделирование режимов работы системы электропривода в среде MatLab. Результаты. Дана характеристика скиповой подъемной машины слепого скипового ствола и еѐ системы электропривода. Проанализированы результаты обследования системы электропривода, полученные как до, так и после ввода установки в промышленную эксплуатацию. Исследованы причины выхода из строя фильтрокомпенсирующего устройства, а также проанализированы причины отказов в работе преобразователя частоты. Сделаны выводы о влиянии высших гармоник на работу преобразователя частоты в условиях подземного рудника. Предложены меры защиты электроустановок от высших гармоник и методы по их снижению. The relevance of the research is caused by the need to identify the reasons of failure of the nodes and parts of the frequency converter, as well as the capacitor of the filter compensating device in the electric drive system of the skip hoist. The failure of this unit during the development of the protection algorithm leads to application of a safety brake to the lifting machine, which has a sufficiently large kinetic energy, which, in its turn, dissipates in the components and parts of the lifting machine, leading to a reduction in their service life. The aim of the research is to determine the degree of influence of higher harmonics in the power supply system of an underground mine on the elements of the frequency converter of the electric drive system of a skip hoist installation and propose methods to reduce them. Objects: frequency converter, electric drive system of a lifting installation, power supply system of an underground mine, other technological installations and their electric drive systems that affect the generation of higher harmonics. Methods: instrumental control of electric energy quality indicators in accordance with the requirements of GOST 32144-2013; mathematical processing and analysis of the results using the MathCAD software; computer simulation of the operation modes of the electric drive system in the MatLab environment. Results. The authors have given the characteristic of a skip hoist machine for a blind skip shaft and its electric drive system and analyzed the results of inspection of the electric drive system obtained both before and after putting the unit into commercial operation. The reasons for the failure of the filter compensating device are investigated, and the causes of failures in the operation of the frequency converter are analyzed. The authors drew the conclusions on the effect of higher harmonics on a frequency converter operation in an underground mine and proposed the measures to protect electrical equipment from higher harmonics and methods for their reduction.

Summary Conventional well plug and abandonment (P&A) can sever and remove the tubing to access casing or leave it in situ when it does not interfere with providing a seal over an indefinite time frame. This paper assesses the viability of pushing rather than pulling severed production tubing to gain casing access. The P&A decision to push, pull, or leave the tubing in situ depends on confirming existing seals and then placing suitable sealants, such as cement, to keep the risks of future well leakages as low as reasonably practicable (ALARP). Pushing or compacting tubing into the liquid space of a well could be used with smaller rigless units, which cannot hoist the production tubing, but can use production intervention or decommissioning logistics with coiled tubing or wireline cutting and severance. Associated pumps could then drive an inflatable piston to compact split and severed tubing into a lower liquid space to access casing for logging and P&A plugging. Rigless tools and methods have provided dramatic cost savings where casing access was not needed, and thus the present study investigates the viability of accessing casing by means of pushing or compacting tubing to extend rigless P&A use and savings. The viability of pushing and compacting North Sea sizes and grades were confirmed in real-scale physical-compaction simulations of production-tubing joints pulled from offshore wells. Independent small-scale physical simulations and numerical modeling then confirmed that the real-scale results were predictable and repeatable to demonstrate an ability to design and provide a window or gap in a production-tubing string for use by other P&A methods.

Mine hoist is a typical flexible lifting system. Due to the cable flexibility, the system is prone to severe shocks and even slippage during emergency braking. To establish a safe emergency braking operation for mine hoist, retarded velocity should be less than the limit deceleration value. The simplified mathematical model shows that the system dynamic response along the longitudinal axis of the wire rope (longitudinal dynamics) is a typical second-order underdamped one. Due to the inherent characteristics of the flexible lifting system, the longitudinal dynamic response under slippage condition exhibits the following characteristics: the response curve deviates from the input signal, that is, the retarded velocities of cable and pulley at their contact points are no longer equal. Based on this finding, deceleration deviation coefficient is defined to normalize the longitudinal response curves, which can help us to determine the extent to which the output signal deviates from the input one; and the sudden increase in the deceleration deviation coefficient is considered as an indicator of rope slippage during emergency braking. The proposed scheme is verified and evaluated by means of simulation model. Subsequent results indicate that the limit deceleration valves obtained by the proposed approach have the same trend and magnitude as those obtained by conventional one, which illustrates that the proposed methodology is feasible. The advantage of the proposed approach is that the solution for each set of operating parameter is unique and certain. As for the conventional approach, the solution is not unique because of the introduction of safety factor, which will cause some trouble to the user. In subsequent work, a test bench will be set up to verify and optimize the proposed scheme.

The main shaft device (MSD) is a key component of the mine hoisting system. During lifting, vibration of the system will cause dynamic tension of wire rope at both ends, resulting in the complex st...

Airway management and maintenance of adequate ventilation during a patient's unattended helicopter rescue hoist extraction present unique challenges to the air medical provider. We present the case of a critically injured patient requiring emergent airway management and subsequent extrication via hoist from challenging, near-vertical terrain, which illustrates the logistical challenges of providing high-quality, neuroprotective mechanical ventilation in an austere air medical scenario.

Dragline excavators are closed-loop mining manipulators that operate using a rigid multilink framework and rope and rigging system, which constitute its front-end assembly. The arrangements of dragline front-end assembly provide the necessary motion of the dragline bucket within its operating radius. The assembly resembles a five-link closed kinematic chain that has two independent generalized coordinates of drag and hoist ropes and one dependent generalized coordinate of dump rope. Previous models failed to represent the actual closed loop of dragline front-end assembly, nor did they describe the maneuverability of dragline ropes under imposed geometric constraints. Therefore, a three degrees of freedom kinematic model of the dragline front-end is developed using the concept of generalized speeds. It contains all relevant configuration and kinematic constraint conditions to perform complete digging and swinging cycles. The model also uses three inputs of hoist and drag ropes linear and a rotational displacement of swinging along their trajectories. The inverse kinematics is resolved using a feedforward displacement algorithm coupled with the Newton-Raphson method to accurately estimate the trajectories of the ropes. The trajectories are solved only during the digging phase and the singularity was eliminated using Baumgarte′s stabilization technique (BST), with appropriate inequality constraint equations. It is shown that the feedforward displacement algorithm can produce accurate trajectories without the need to manually solve the inverse kinematics from the geometry. The research findings are well in agreement with the dragline real operational limits and they contribute to the efficiency and the reduction in machine downtime due to better control strategies of the dragline cycles.

One of the main power stations in Zimbabwe has its generators located 100m underground. Elevators that used to carry people to the underground plant are not functional anymore due to old age and corrosion of the hoist way blade and guide rails. A system with an electromagnet actuator attached to the elevator car and its core shaped in the form of the letter ‘E’ used for coupling the magnetic flux between the coil and the hoist way rail blades was designed. Pairs of coils are wound on the actuator core in a manner that produces both side-to-side and front-to-back forces that are controlled by adjusting the current being supplied to the coils. The electromagnets fixed to the car supply the force of attraction between the actuator and guide rail, which then keep the car suspended; the motor is used to provide a driving force for the up and down movement of the car. The research satisfied the 9th Sustainable Development Goal of 2015, thereby contributing towards sustainability.

This article proposes a new technology of container carriage of rocks without construction of transport communications in an open-pit mine and with technological and energy-saving advantages. These advantages are: simultaneous excavation of rocks, transportation of rocks by the shortest distance, small mass of a container and mobility of a complex of hoists which will reduce energy expenses and the cost of transportation of the mined rock. One of the principal advantages of the developed technology is the decrease in environmental emissions into the atmosphere of the open-pit mine thanks to the reduction of the vehicle fleet. This technology will enable significant improvement of the environmental situation in the area of mining operations.

This paper studies a modular permanent magnet synchronous machine (MPMSM) converted from a traditional single-core 24-slot 20-pole tooth-coil winding permanent magnet synchronous machine (TCW PMSM). The performance of the TCW PMSM is compared with the performance of the MPMSM (rearranged from this TCW PMSM) by the finite element method (FEM). It is found that if an electrical machine with a modular structure is designed, the efficiency of the MPMSM may be degraded compared with the conventional structure, especially, if a solid rotor yoke is used. However, the advantages of the proposed MPMSM are related to an option to scale up the machine by applying a certain number of modules, or removing faulty modules (while keeping the healthy modules working). This makes this type of a motor design applicable in certain life-critical applications, or in applications where scaling of the motor power might be needed. As a prototype, a low-power, low-speed generator added to a hook block of a hoist to supply power to measurement electronics is studied.

A lifting hook is a device for grabbing and lifting loads by means of a device such as a hoist or a crane. A lifting hook is usuallyequipped with a safety latch to prevent the disengagement of the lifting wire rope sling, chain or rope to which the load is attached. Crane hook is always subjected to failure due to the accumulation of a large amount of stress concentration which caneventually lead to its failure. To study the stress pattern of crane hook in its loaded condition, a solid model of crane hook isprepared with the help of Solid Works 19.0 software. The pattern of stress distribution in the 3D model of the crane hook isobtained using ANSYS 19.2 software. In this present work, the obtained stresses by using finite element analysis and the WinklerBatch method in different cross-sections are compared & to reduce the stress formed in sections by changing its designparameters (changing the mass of material in trapezoidal section). The stress concentration factors are used in strength anddurability evaluation of structure and machine elements. It is observed that stress is affected if the weight is increased.

In industrial production, there are strict requirements for the braking effect of heavy transport equipment such as elevator and belt conveyor. The working capacity and reliability of the brake are the basis for ensuring efficient production. Based on the friction and wear test, taking the average friction coefficient and stable wear rate as the key parameters to measure the reliability and stability of the brake, the friction and wear characteristics of the hydraulic disc brake of the hoist under different working conditions are analyzed and studied. The results shows that the average friction coefficient and stable wear rate of the brake fluctuate less with the change of brake pressure in the middle speed range. At this time, the adhesive and matrix fiber in the friction pad have not been decomposed and modified, and the strength and shape of the surface micro convex structure are relatively moderate, so the braking reliability is in good condition.

Introduction Optimal dispatch of emergency medical services relies on accurate time estimates of the various prehospital stages. Hoist rescue work time intervals performed by the search and rescue (SAR) helicopter service in Norway have not been studied to date. We aimed to describe the epidemiologic, operational, and medical aspects of the SAR service in southeast Norway. To complement the prehospital timeline, we performed simulated hoist operations. Methods We reviewed time and patient descriptors and medical interventions in hoist operations performed at a SAR base over 5 y. In addition, a simulation study measuring hoist rescue time intervals was performed. Data are presented as mean ± SD, except National Advisory Committee for Aeronautics (NACA) scores, which are presented as modes. Results There were 148 hoist operations performed during the study period, involving 180 patients. Time to take-off was 13 ± 7 min. There were 88 patients (49%) who were injured; 53 (29%) had a medical condition, and 39 (22%) were evacuees. The mode of the NACA score was 3. Forty-five patients (25%) had an NACA score of 4 to 6. Medical interventions were performed on 77 patients (43%) in 73 operations (49%). Nine patients (5%) were endotracheally intubated, and 1 thoracostomy was performed. The simulated rescuer access time was 4 ± 2 min, the simulated anesthesiologist access time was 6 ± 2 min, and the simulated hoist extrication time was 13 ± 2 min. Conclusions Hoist rescue was performed in 10% (n=148) of the SAR operations. New information about hoist extrication time intervals can improve rescue helicopter dispatch accuracy.

In this paper, an improved Model Reference Adaptive Controller is designed to synchronize speed of two BLDMs of a dual channel hoist. Due to ability of disturbance rejection is enhanced by proposed control method, both channels with different load could track the dynamic respond of reference model. Speed synchrony during transient state is much better improved which significantly narrows the position error finally. Stability of method is proven based on Lyapunov theorem, and effectiveness is verified by simulation.

In order to realize automatic detection of corrosion on the piston rod of hydraulic hoist of hydropower station, it is important to find the location of corrosion and prevent oil leakage of hydraulic hoist and the blocking of control valve or other adverse consequences. A quick and convenient inspection robot for piston rod of hydraulic hoist is developed. Firstly, according to the specific working requirements of the piston rod of the hydraulic hoist of hydropower station and the basic principle of the robot, the structure scheme of the design of the testing robot is put forward. Then the robot control system is designed for the detection robot, and the basic idea of image recognition is introduced. Next the human-computer interaction interface is designed. Finally, the performance of the detection robot was tested to verify whether the reliability of the robot and the accuracy of image recognition meet the design objectives, and to ensure that the performance of the piston rod detection robot meets the design requirements..

As a global vibration characteristic, natural frequency often suffers from insufficient sensitivity to structural damage, which is associated with local variations of structural material or geometric properties. Such a drawback is particularly significant when dealing with the large scale and complexity of sluice structural systems. To this end, a damage detection method in sluice hoist beams is proposed that relies on the utilization of the local primary frequency (LPF), which is obtained based on the swept frequency excitation (SFE) technique and local resonance response band (LRRB) selection. Using this method, the local mode of the target sluice hoist beam can be effectively excited, while the vibrations of other components in the system are suppressed. As a result, the damage will cause a significant shift in the LPF of the sluice hoist beam at the local mode. A damage index was constructed to quantitatively reflect the damage degree of the sluice hoist beam. The accuracy and reliability of the proposed method were verified on a three-dimensional finite element model of a sluice system, with the noise resistance increased from 0.05 to 0.2 based on the hammer impact method. The proposed method exhibits promising potential for damage detection in complex structural systems.

A reliable braking system is an important guarantee for safe operation of mine hoist. In order to make full use of the monitoring data in the operation process of mine hoist, identify the operation status of the hoist, and further carry out fault diagnosis on it, the deep learning method was introduced into the fault diagnosis of the hoist, and a fault diagnosis method of hoist braking system based on convolution neural network has been proposed. Firstly, the working principle and fault mechanism of disc brake and its hydraulic station in hoist braking system are analyzed, and the monitoring parameters of this study are determined; then, based on massive monitoring data, the convolutional neural networks (CNN) is established, the one-dimensional signal collected by the sensor is transformed into two-dimensional image for coding, the neural network is trained by gradient descent method, and the network structure parameters are modified according to the training results. Finally, the fault diagnosis model is compared and verified by using the sample set based on the traditional back propagation neural network (BP) and CNN. The results show that the accuracy of CNN is higher than that of BP, and the accuracy rate can reach 99.375% after reducing the involvement between samples. This method can make full use of the monitoring data for diagnosis, without subjective intervention of experts, and improve the accuracy of diagnosis.

Coal machinery equipment virtual reality model resource library is the basis of the establishment of coal machinery equipment oriented virtual reality assembly system. According to the different characteristics of shearer, scraper conveyor, road header and hoist structure and actual work, the structure is divided in detail, and the virtual reality model resource library is established. In the follow-up work, it is further realized by programming to complete the designed functions.

Objective We aimed to investigate the medical characteristics of helicopter hoist operations (HHO) in HEMS missions. Methods We designed a retrospective study evaluating all HHO and other human external cargo (HEC) missions performed by Swiss Air-Rescue (Rega) between January 1, 2010, and December 31, 2019. Results During the study period, 9,963 (88.7 %) HEMS missions with HHO and HEC were conducted during the day, and 1,265 (11.3 %) at night. Of the victims with time-critical injuries (NACA ≥ 4), 21.1 % (n = 400) reached the hospital within 60 min during the day, and 9.1 % (n = 18) at night. Nighttime missions, a trauma diagnosis, intubation on-site, and NACA Score ≥ 4 were independently and highly significantly associated with longer mission times (p n = 3,731, 37.5 %) while practicing recreational activities (n = 5,492, 55.1 %). In daytime HHO missions, the most common medical interventions performed were insertion of a peripheral intravenous access (n = 3,857, 38.7 %) and administration of analgesia (n = 3,121, 31.3 %). Conclusions Nearly 20 % of patients who needed to be evacuated by a hoist were severely injured, and complex and lifesaving medical interventions were necessary before the HHO procedure. Therefore, only adequately trained and experienced medical crew members should accompany HHO missions.

In view of the complex environment and frequent faults in the actual operation of mine hoist, a fault diagnosis method based on Convolution Attention Autoencoder (CAAE) is proposed through theoretical analysis and experimental verification to improve the diagnostic stability of mine hoist under strong noise. First, a CAAE is constructed, which uses a combination of a convolutional neural network (CNN) and a channel attention module (CAM) to compress and encode the input signal, and then the input signal is reconstructed by a decoder to train the CAAE to extract the original signal fault features. Then, a fault diagnosis classifier is constructed to classify different fault patterns. Finally, experimental validation is performed with the Case Western Reserve University bearing dataset. The results show that the method has a strong feature extraction capability and a high classification accuracy for bearing failure modes compared with existing methods. And the experiments on the application effect of the proposed method in noisy environment are conducted to verify that the method is highly effective and challenging.

The effects of vibration on the emergency braking tribological behaviors of the brake shoe of a deep coal mine hoist were investigated in this study. The thermal, frictional and mechanical parameters of the brake shoe were obtained. The vibration characteristics of the brake shoe during emergency braking were investigated, employing multibody dynamics analysis. The effect of vibration on the emergency braking tribological behaviors (temperature and stress distributions) of brake interfaces was explored using the finite element method. The self-made tribo-brake test rig of a brake shoe was employed to reveal the friction deterioration behaviors of the brake shoe during emergency braking. The results show obvious vibrations of all brake shoes along the direction of positive braking pressure during emergency braking. The vibration causes increases in the equivalent Von Mises stress and temperature at the contact interfaces between the brake disc and the brake shoe as compared to the case of ignoring the vibration. Along the rotation direction of the brake disc, the equivalent stress and temperature of the brake disc surface present three overall rapid increases, as well as two slight decreases during emergency braking. As compared to cyclic emergency braking, continuous emergency braking exhibits more obvious tribological degradation of the brake shoe, attributed to enhanced vibration. The wear loss of the brake shoe increases with increasing emergency braking cycles and continuous emergency braking time.

“Men hoist the banner of the ideal, and then march in the direction that concrete conditions suggest and reward.” (Dewey 2013 [1929], 267)A rich interdisciplinary discussion of the role of social s...

Background: The brake is an important safety protection device for mine hoists, in which the performance of the brake shoe affects directly the safe operation of the hoist system. In order to solve problems such as high wear rate and unstable friction coefficient of brake shoe under high temperature, this paper indicated that adding magnetic powder to the composite material of traditional mine hoist’s brake shoe will be a creative and effective approach to improve its properties. Methods: Based on relevant China patents of the authors, several new formulas of brake shoe material were designed in the presence of Nano-Fe3O4 and Nd-Fe-B, and the methods of both preparation and performance testing of the magnetic brake shoes were introduced. The experiment of formula design was carried out by uniform prescription design, and the friction coefficient and wear rate of each kind of brake shoes made through different formulas were measured. Furthermore, the formula was optimized by application of fuzzy comprehensive evaluation method and analytic hierarchy process. Results: Compared with ordinary formulas, the optimized formula is higher totally and changes more steadily as well. Its wear rate is far lower than the national standard. Namely, its comprehensive properties are better. Few relevant patents to the topic have been reviewed and cited. Conclusion: This paper proved that it is practically valuable and feasible to improve the properties of hoist brake shoes by adding magnetic powder to its composite material.