Download Dynamics and Simulation of Flexible Rockets Ebook PDF

Dynamics and Simulation of Flexible Rockets provides a full state, multiaxis treatment of launch vehicle flight mechanics and provides the state equations in a format that can be readily coded into a simulation environment. Various forms of the mass matrix for the vehicle dynamics are presented. The book also discusses important forms of coupling, such as between the nozzle motions and the flexible body. This book is designed to help practicing aerospace engineers create simulations that can accurately verify that a space launch vehicle will successfully perform its mission. Much of the open literature on rocket dynamics is based on analysis techniques developed during the Apollo program of the 1960s. Since that time, large-scale computational analysis techniques and improved methods for generating Finite Element Models (FEMs) have been developed. The art of the problem is to combine the FEM with dynamic models of separate elements such as sloshing fuel and moveable engine nozzles. The pitfalls that may occur when making this marriage are examined in detail. Covers everything the dynamics and control engineer needs to analyze or improve the design of flexible launch vehicles Provides derivations using Lagrange’s equation and Newton/Euler approaches, allowing the reader to assess the importance of nonlinear terms Details the development of linear models and introduces frequency-domain stability analysis techniques Presents practical methods for transitioning between finite element models, incorporating actuator dynamics, and developing a preliminary flight control design

"This book describes how to build mathematical models of multibody systems with elastic components. Examples of such systems are the human body itself, construction cranes, cars with trailers, helicopters, spacecraft deploying antennas, tethered satellites, and underwater maneuvering vehicles looking for mines while being connected by a cable to a ship"--

Volume is indexed by Thomson Reuters CPCI-S (WoS). The collection includes selected peer-reviewed papers from the 2012 International conference on Mechanics , Dynamic Systems and Material Engineering (MDSME2012) held November 24-25, 2012 in Guangzhou, China. The 70 papers are grouped into the following chapters: Chapter 1: Research on Mechanics and Dynamics of Systems in Mechanical Engineering, Chapter 2: Research on Material Engineering and Material Applications.

As launch vehicle designs become more slender, the effects of bending vibration on control system stability could be dominant in control systems designed using rigid-body dynamics. Vibrational loads can also cause major damage to the launch vehicle, either in the form of vibrational fatigue or excitation of the structures resonant frequencies. This work investigates a novel method to control vibrations in real time using a real time control target with distributed strain measurements from FBG sensor arrays. Active control of the flexible structure will reduce vibration, which will decrease the chance of damaging the structure. A scaled test article representative of the structural dynamics associated with a slender launch vehicle is designed and built. Finite element analysis modeling methodology is developed to capture the most significant features of test specimen. A model for the entire test article is developed, including frequency response of the cantilever beam, thruster dynamics, and sensor conversion matrices. This research develops, models and provides experimental validation of the use of an array of cold gas thrusters for the real time control of the bending dynamics of a test article. Three separate control algorithms are developed to minimize vibration in the test article, using the FBG strain measurements to calculate required thrust. A classical control algorithm for benchmark purposes, a robust control algorithm and an adaptive control algorithm are implemented. The controller performance is investigated by simulation using the developed model, and these results are experimentally verified using the experimental setup. The performance comparison shows that classic controller is hard to implement experimentally due to decoupling issues, the robust controller achieves good vibration suppression in both simulations and experimental results, and the adaptive controller shows good results, with a potential to surpass the robust controller results in future research. Using the robust controller to control the continuous excited first and second resonant mode of the test setup, shows 94% and 80% reduction of peak-peak vibration respectively, when compared to the open loop response. This research also investigates using the same FBG sensor arrays to reduce the number of IMU sensing units in the launch vehicle.