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This study was a result from research on repairing project of damaged elevator gear box. The objective of this research is to analyze the failure part on elevator gearbox at flourmill factory. The equipment was damaged after one year installed and running on factory. Severe wear was occurred on high speed helical gear. These helical gear was one of main part of elevator gearbox in flour mill manufacture. Visually, plastic deformation didn’t occurred and not visible on the failure helical gear shaft. Some test would be performed to check the chemical composition, microstructure and hardness of failure helical gear. The material of failure helical gear shaft was a medium carbon steel alloy. The microstructure was showed a martensitic phase formed on the surface to the center area of gear shaft. Otherwise, the depth of hardness layer slight formed on surface and lack depth of hardness layer was a main trigger of severe wear. It was not enough to resist wear due to friction caused by rolling and sliding on surface between high speed gear and low speed gear. Enhancement of hardness layer on surface and depth of hardness layer will make the component has more long life time. Furthermore, to perform next research is needed to analyze the reliability of enhanced hardness on layer and depth of hardness layer on helical gear shaft.

The guided missiles flight control system is essential for guidance accuracy and kill probability. It is complicated and fragile. Since actuator faults and sensor faults could seriously affect the security and reliability of the system, fault detection for missiles flight control system is of great significance. This paper deals with the problem of fault detection for the closed-loop nonlinear model of the guided missiles flight control system in the presence of disturbance. First, set up the fault model of flight control system, and then design the residual generation based on the extended Kalman filter (EKF) for the Eulerian-discrete fault model. After that, the Chi-square test was selected for the residual evaluation and the fault detention task for guided missiles closed-loop system was accomplished. Finally, simulation results are provided to illustrate the effectiveness of the approach proposed in the case of elevator fault separately.

When an aircraft is locked in a stable equilibrium at high angle-of-attack, we have to do with the so-called deep stall which is a very dangerous situation. Airplanes with T-tail are mainly concerned with this phenomenon since the wake of the main wing flows over the horizontal tail and renders it ineffective but other aircrafts such as fighters can also be affected.First the phase portrait and bifurcation diagram are determined and characterized (with three equilibria in a deep stall prone configuration). It allows to diagnose the configurations of aircrafts susceptible to deep stall and also to point out the different types of time evolutions. Several techniques are used in order to determine the basin of attraction of the stable equilibrium at high angle-of-attack. They are based on the calculation of the stable manifold of the saddle-point equilibrium at medium angle-of-attack.Then several ways are explored in order to try to recover from deep stall. They exploits static features (such as curves of pitching moment versus angle-of-attack for full pitch down and full pitch up elevators) or dynamic aspects (excitation of the eigenmodes and improvement of the aerodynamic efficiency of the tail).Finally, some properties of a deep stall prone aircraft are pointed out and some control tools are also implemented. We try also to apply this mathematical results in a concrete situation by taking into account the captors specificities or by estimating the relevant variables thanks to other available information.

The present work is devoted to the study of a new type of bearing surface with the ability to optimize interaction with the medium, as well as controlling the movement in space.

In this modern era, elevators have become an integral part of any commercial or public complex. It facilitates the faster movement of people and luggage between floors. The lift control system is one among the keenest aspects in electronics controlling module that are used in auto motive filed. Usually elevators are designed for a specific building taking into account the main factors like the measure of the building, the count of persons travelling to each floor and the expected periods of large usage. The lift system was designed with different control strategies. This implementation is based on FPGA, which could be used for any building with any number of floors, with the necessary inputs and outputs. This controller can be implemented based on the required number of floors by merely changing a control variable from the HDL code. This approach is based on an algorithm which reduces the number of computation necessary, on concentrating only on the relevant principles that improves the score and ability of the club of elevator structure. The elevator controller is developed using Verilog HDL and is perfectly executed on a Xilinx ISE 12.4 and Spartan –3E FPGA.

Falling particle receivers (FPR) utilize small particles as a heat collecting medium within a cavity receiver structure. Previous analysis for FPR systems include computational fluid dynamics (CFD), analytical evaluations, and experiments to determine the feasibility and achievability of this CSP technology. Sandia National Laboratories has fabricated and tested a 1 MWth FPR that consists of a cavity receiver, top hopper, bottom hopper, support structure, particle elevator, flux target, and instrumentation. Design requirements and inherent challenges were addressed to enable continuous operation of flowing particles under high-flux conditions and particle temperatures over 700 °C. Challenges include being able to withstand extremely high temperatures (up to 1200°C on the walls of the cavity), maintaining particle flow and conveyance, measuring temperatures and mass flow rates, filtering out debris, protecting components from direct flux spillage, and measuring irradiance in the cavity. Each of the major c...

Steel wire ropes, which are usually composed of a polymer core and enclosed by twisted wires, are used to hoist heavy loads. These loads are different structures that can be clamshells, draglines, elevators, etc. Since the loading of these structures is dynamic, the ropes are working under fluctuating forces in a corrosive environment. This consequently leads to progressive loss of the metallic cross-section due to abrasion and corrosion. These defects can be seen in the forms of roughened and pitted surface of the ropes, reduction in diameter, and broken wires. Therefore, their deterioration must be monitored so that any unexpected damage or corrosion can be detected before it causes fatal accident. This is of vital importance in the case of passenger transportation, particularly in elevators in which any failure may cause a catastrophic disaster. At present, the widely used methods for thorough inspection of wire ropes include visual inspection and magnetic flux leakage (MFL). Reliability of the first method is questionable since it only depends on the operators’ eyes that fails to determine the integrity of internal wires. The later method has the drawback of being a point by point and time-consuming inspection method. Ultrasonic guided wave (UGW) based inspection, which has proved its capability in inspecting plate like structures such as tubes and pipes, can monitor the cross-section of wire ropes in their entire length from a single point. However, UGW have drawn less attention for defect detection in wire ropes. This paper reports the condition monitoring of a steel wire rope from a hoisting elevator with broken wires as a result of corrosive environment and fatigue. Experiments were conducted to investigate the efficiency of using magnetostrictive based UGW for rope defect detection. The obtained signals were analyzed by two time-frequency representation (TFR) methods, namely the Short Time Fourier Transform (STFT) and the Wavelet analysis. The location of the defect and its severity were successfully identified and characterized.

Lifts or elevators are an essential part of multistorey buildings which provide vertical transportation for its occupants. In large and high-rise apartment buildings, its occupants are permanent, while in buildings, like hospitals or office blocks, the occupants are temporary or users of the buildings. They come in to work or to visit, and thus, the population of such buildings are much higher than those in residential apartments. It is common these days that large office blocks or hospitals have at least 8 to 10 lifts serving its population. In order to optimize the level of service performance, different transportation schemes are devised to control the lift operations. For example, one lift may be assigned to solely service the even floors and another solely for the odd floors, etc. In this paper, a basic lift system is modelled using SAS Simulation Studio to study the effect of factors such as the number of floors, capacity of the lift car, arrival rate and exit rate of passengers at each floor, peak ...

This paper presents a study into the testing methods to estimate rated damping and stiffness characteristics of lift passengers. In prediction of the dynamic behaviour of a lift car system, it is important to take into account the influence of passengers' behaviour in the car. An experimental rig with a rectangular elevator car platform supported by four silent blocks attached to a shaker is designed to conduct experimental tests. The platform with no load and loaded with one passenger from a sample of twelve passengers of different age, mass and height, wearing various types of shoes, is excited harmonically over a range of frequencies and amplitudes. A mathematical model of the system is developed and the vertical acceleration transmissibility function is derived. The experimental results are compared with predictions obtained from the mathematical model. Then statistical treatment is applied to estimate the rated damping and rated stiffness characteristics of lift passengers.

Because the flight performance of aircraft is so dependent on aerodynamic efficiency of elevator, it is very important to improve the flow separation over the control surfaces at high deflection angle in order to keep the aircraft having good flight capability, especially for the modern aircraft with tailless aerodynamic configuration. A new flow control technique to improve the flow separation over the control surface by microblowing at the flow separated position is discussed in this paper. Furthermore, the effect of the various blowing parameters are also investigated in detail, and based on these studies, the parameter similarity about this flow control technique is discussed.

The Vertical conveyers have a cylindrical casing, a helical open trough or closed pipe is attached at the outside or at the inside of the vertical tubular casing, along which the load can be transported from the bottom upwards. A vibration‐exciting drive is mounted at the top or bottom of the casing to impart to the latter directed vibrations along and around the vertical axis, which cause the load to move upwards along the helix. In this work, nonlinear analysis for the change of the parameters of the motion, stability condition, and the jump phenomena has been shown graphically.

In this paper hot forging process for industrial locking gear elevators is simulated and analyzed. An increase in demand of industrial locking gear elevators with better quality and lower price caused the machining process to be replaced by hot forging process. Production of industrial locking gear elevators by means of hot forging process is affected by many parameters such as billet temperature, geometry of die and geometry of pre-formatted billet. In this study the influences of billet temperature on effective plastic strain, radius of die corners on internal stress of billet and thickness of flash on required force of press are investigated by means of computer simulation. Three-dimensional modeling of initial material and die are performed by Solid Edge, while simulation and analysis of forging are performed by Super Forge. Based on the computer simulation the required dies are designed and the workpieces are formed. Comparison of simulation results with experimental data demonstrates great compatibility.

The inclusion of a soft storey in multistory concrete buildings is a feature gaining popularity in urban areas where land is of exorbitant cost. In earthquake prone zones, this feature has been observed in post earthquake investigations. Although engineers are prepared to accept the notion that a soft storey poses a weak link in Seismic Design, yet the idea demands better understanding. The following study illustrates the importance of the judicious distribution of shear walls. The selected building is analyzed through nine numerical models which address the behavior of framed structures. The parameters discussed include, inter alias, the fundamental period of vibration, lateral displacements, axial and shear forces. It is noticed that an abrupt change in stiffness between the soft storey and the level above is responsible for increasing the strength demand on first storey columns. Extending the elevator shafts throughout the soft storey is strongly recommended.

The elevator has a cylindrical casing, a helical open trough or closed pipe is attached at the outside or at the inside of the vertical tubular casing, along which the load can be transported from the bottom upwards. In this work, the change of the parameters of the motion has been shown graphically in Mathematica software. Obtained results are compared the results in the literature and it is realized the general tendency are approximately same.

A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

Testing the Equivalence Principle (EP) at a level of accuracy substantially higher than the present state of the art requires resolving a very small signal out of the instrument’s intrinsic noise and also the noise associated with the instrument’s motion and gravity gradients. In the test of the Equivalence Principle in an Einstein Elevator under development by our team, the acceleration detector spins about a horizontal axis while free falling for about 25 s inside a co‐moving capsule released from a stratospheric balloon. The characteristics of the instrument package and the configuration of the detector play a key role in the ability to extract an EP violation signal at the desired threshold level out of dynamics‐related noise. Numerical simulations of the detector’s dynamics in the presence of relevant perturbations, having assumed realistic errors and construction imperfections, show the merits of the detector configuration selected. The results illustrate that the effects of dynamics and gravity gra...

The Space Elevator is conceived to be a carbon nanotube ribbon stretching from an Earth station in the ocean on the equator to far beyond geosynchronous altitude. This elevator co‐rotates with the Earth. Climbers ascend the ribbon using power beamed from Earth to launch spacecraft in orbit or to other worlds. The requirements of the ribbon material, challenges to the building of the space elevator, deployment and the promise of the space elevator are briefly discussed in this paper.

Technological advances and recent studies have laid the groundwork for eventual construction of a space elevator. Within 15 years an operational space elevator could be running from Earth to beyond geosynchronous. The basic mechanical operation allows for low operational cost ($250/kg), high capacity (>13tons, >5tons/day/elevator), a range of destinations (LEO, GEO, Moon, Mars, Asteroids, and Venus), and minimal launch forces. The low risk operation of the space elevator would allow large scale robotic and human exploration of the solar system. An operational elevator will immediately move primary interest from LEO to GEO for many activities and open commercial space activities such as solar power satellite arrays for beaming power to Earth. Robotic exploration to all destinations would be able to use larger, fixed structures, more massive platforms and be launched for a fraction of current costs. Human exploration could start at GEO for maintaining commercial assets, and enhanced Earth‐observing systems and then step to Mars where a receiving elevator could also be established. This paper will cover the basics of a space elevator and a comprehensive strategy for human and exploratory use of space based on the space elevator.

A novel approach is examined for creating an industrial civilization beyond Earth. The approach would take advantage of the unique configuration of Mars and its moon Phobos to make a transportation system capable of raising mass from the surface of Mars to space at a low cost. Mars would be used as the primary location for support personnel and infrastructure. Phobos would be used as a source of raw materials for space‐based activity, and as an anchor for tethered carbon‐nanotube‐based space‐elevators. One space‐elevator would terminate at the upper edge of Mars’ atmosphere. Small craft would be launched from Mars’ surface to rendezvous with the moving elevator tip and their payloads detached and raised with solar powered loop elevators to Phobos. Another space‐elevator would be extended outward from Phobos to launch craft toward the Earth/Moon system or the asteroid belt. The outward tip would also be used to catch arriving craft. This approach would allow Mars to be colonized, and allow transportation of people and supplies from Mars to support the space industry. In addition, large quantities of material obtained from Phobos could be used to construct space habitats and also supply propellant and material for space industry in the Earth/Moon system as well as around Mars.

The Bridge to Space (BTS), an advanced system concept designed to significantly reduce payload-to-space delivery costs, consists of two major elements as seen in Figure 1: a long Space Elevator cable structure and an aircraft-like Sub-Orbital launch vehicle (SOLV). Preliminary estimates indicate the BTS can meet a launch cost target of $100/lb for 3rd generation launch systems. Previous papers have described the operational concept for launching payloads with the Bridge to Space (Marshall & Mottinger, 2000). These operations include payload transfer from the SOLV to the Space Elevator’s Earth Transfer Station (ETS), payload translation along the elevator with a moving carriage platform and processing/transfer/release of the payload at the elevator’s Apex Station (AS) as required, or payload release at the uppermost point of the elevator, the Space Transfer Station (STS). This paper will focus on sizing and performance modeling of the Space Elevator segment of the overall Bridge to Space. An elevator model...

The Bridge-To-Space (BTS) is an advanced system concept that is designed to significantly reduce costs in delivering payloads to space. The BTS architecture provides the potential for achieving third generation launch system target costs of $100/lb to low earth orbit (LEO) and geosynchronous earth orbit (GEO). The BTS is comprised of two major elements: a long Space Elevator cable structure and an aircraft-like Sub-Orbital Launch Vehicle (SOLV), as shown in Figure 1. A BTS operations overview is provided in the paper. Key operations include: payload transfer from the SOLV to the Space Elevator’s Earth Transfer Station (ETS), payload translation along the elevator with a moving carriage platform, processing/transfer/release of the payload at the Apex Station (AS) as required, or payload release at the Space Transfer Station (STS). The paper provides background information on the two main factors that lower the “access to space” costs for the BTS system. These include reduced SOLV energy needed for payload ...