Impact of building sway on in-car vibration of ultrahigh-rise elevators — multiphysics simulation approach

High-rise, high-speed elevators are subjected to both static and dynamic loads. They are transferred into the elevator and perceived as in-car vibrations. Building sway is one of the main contributors to in-car vibration for high-rise elevators. Vibrations transferred into the elevator is greatly influenced by the response of building sway amplitudes. A finite element model of the elevator was developed using ABAQUS/Standard. Transient dynamic simulation method was utilized to compute the in-car vibrations. Various subroutines were used to include the installation inaccuracies over the travel distance. Aerodynamic loads calculated using computational fluid dynamics were used in the finite element model as pressure loads acting over a specified time interval. Finite difference method was used to study the rope behavior for different building sway amplitudes and elevator speed profiles. The rope forces calculated using this method is extracted and applied in the finite element simulation. The output of each computations is expressed as in-car vibration amplitudes. This thesis mainly focuses on the prediction of in-car vibration due to building sway for a specific elevator configuration. Human perception of the vibration and the discomfort caused to the passengers because of the in-car vibration is investigated. Finally, the thesis proposes an optimized speed profile approach to mitigate this problem. 51 combinations of various building sway amplitude and speed profiles are computed using finite element method. Multiple regression model function is developed by curve fitting and validated against the test data. The generated function helps to predict the optimized speed profile that needs to be followed in order to maintain the required ride comfort. Also, the benefits of optimized speed profile is demonstrated by using handling capacity assessment calculations

Lateral response and energetics of cable-guided hoisting system with time-varying length

The lateral response, energetics and stability of the cable-guided hoisting system that differs from the rail-guided, such as elevator systems, is investigated in this paper. While the equations of motion are established by Hamilton's principle, the boundary conditions are obtained to calculate the natural frequencies with the modified velocity of wave propagation. Then, the governing equation is transformed into a set of ordinary differential equations through the Galerkin method and the rate of change in the energy is derived from the control volume viewpoint. The system frequencies, response of each order and energy characteristics are analyzed. The results show that the system frequencies first decrease, and then increase with the increase of the length and demonstrate that the modified velocity of wave propagation is reasonable by comparison of three approaches. The presented method proves to be effective to obtain the response of each order. According to Lyapunov’s second method, the rate of change in the energy indicates the cable-guided hoisting system experiences stability and instability during downward and upward movements, respectively

Dynamical systems : mechatronics and life sciences

Proceedings of the 13th Conference „Dynamical Systems - Theory and Applications" summarize 164 and the Springer Proceedings summarize 60 best papers of university teachers and students, researchers and engineers from whole the world. The papers were chosen by the International Scientific Committee from 315 papers submitted to the conference. The reader thus obtains an overview of the recent developments of dynamical systems and can study the most progressive tendencies in this field of science

Robotics 2010

Without a doubt, robotics has made an incredible progress over the last decades. The vision of developing, designing and creating technical systems that help humans to achieve hard and complex tasks, has intelligently led to an incredible variety of solutions. There are barely technical fields that could exhibit more interdisciplinary interconnections like robotics. This fact is generated by highly complex challenges imposed by robotic systems, especially the requirement on intelligent and autonomous operation. This book tries to give an insight into the evolutionary process that takes place in robotics. It provides articles covering a wide range of this exciting area. The progress of technical challenges and concepts may illuminate the relationship between developments that seem to be completely different at first sight. The robotics remains an exciting scientific and engineering field. The community looks optimistically ahead and also looks forward for the future challenges and new development

NASA Thesaurus. Volume 2: Access vocabulary

The NASA Thesaurus -- Volume 2, Access Vocabulary -- contains an alphabetical listing of all Thesaurus terms (postable and nonpostable) and permutations of all multiword and pseudo-multiword terms. Also included are Other Words (non-Thesaurus terms) consisting of abbreviations, chemical symbols, etc. The permutations and Other Words provide 'access' to the appropriate postable entries in the Thesaurus

Space station systems: A bibliography with indexes (supplement 10)

This bibliography lists 1,422 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to researchers, designers and managers engaged in Space Station technology development and mission design. Coverage includes documents that define major systems and subsystems related to structures and dynamic control, electronics and power supplies, propulsion, and payload integration. In addition, orbital construction methods, servicing and support requirements, procedures and operations, and missions for the current and future Space Station are included

Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018