Active Control of Initial Disturbances for Rockets and Missiles

The active control theory and methods of initial disturbances for rockets and missiles are investigated. The rocket or missile/launcher is simplified as a flexible beam excited by a moving varying velocity rigid body which has two points in contact with the beam. The control force is applied at the supporting point on the beam. Active control strategies based on optimal control theory are proposed and computer simulation is carried out. Simulation results are consistent with the theoretical results, and show that the active control strategies proposed can accomplish the purpose to control the initial disturbances actively. The results show that active control of initial disturbances for rockets and missiles is feasible for application.

Estimation of Initial Disturbances for Rockets Based on Interactions of Rockets and Directional Tubes

In the range of the rockets/launcher system itself, the dynamic equations for rocket and directional tube during semi-constraint period have been constructed by using Newton-Ether method. Considering the interaction of rockets and directional tubes when clearances exist, the method of estimating initial disturbances for the rocket by using vibration data of the directional tube has been given. The estimated results have been compared with the simulation results computed by the dynamic simulating software ADAMS. Results computed by the two methods are basically consistent and the computing errors do not increase with the variation of the clearance. The validity of the proposed method has been proved.

An efficient and modular modeling for launch dynamics of tubed rockets on a moving launcher

This paper develops a modular modeling and efficient formulation of launch dynamics with marching fire(LDMF)using a mixed formulation of the transfer matrix method for multibody systems(MSTMM)and Newton-Euler formulation.Taking a ground-borne multiple launch rocket systems(MLRS),the focus is on the launching subsystem comprising the rocket,flexible tube,and tube tail.The launching subsystem is treated as a coupled rigid-flexible multibody system,where the rocket and tube tail are treated as rigid bodies while the flexible tube as a beam with large motion.Firstly,the tube and tube tail can be elegantly handled by the MSTMM,a computationally efficient order-N formulation.Then,the equation of motion of the in-bore rocket with relative kinematics w.r.t.the tube using the Newton-Euler method is derived.Finally,the rocket,tube,and tube tail dynamics are coupled,yielding the equation of motion of the launching subsystem that can be regarded as a building block and further integrated with other subsystems.The deduced dynamics equation of the launching subsystem is not limited to ground-borne MLRS but also fits for tanks,self-propelled artilleries,and other air-borne and naval-borne weapons undergoing large motion.Numerical simulation results of LDMF are given and partially verified by the experiment.

Manned Carrier Rockets Empower China's Space Dream

Rong Yi,chief designer of the Long March-2F rocket that has launched China’s all manned space flight missions,talks about China’s progress in manned carrier rocket development and launch vehicle technology.AT 10:44 am on June 5,the gaze of TV audiences globally riveted on the Long March-2F Y14 carrier rocket launch at northwest China’s Jiuquan Satellite Launch Center.About 577 seconds later,the Shenzhou-14 crewed spaceship separated from the rocket and entered its designated orbit.

Hypothetical Dark Matter/Axion Rockets: And the Neutrinos without SUSY Problem

We present Dark Matter candidates from non SUSY processes, in a way emphasizing how a Dark Matter (DM) candidate of roughly 100 - 400 GeV could be formed. As has been said about the Photon rocket and Axions rockets, the presence of a magnetic field supposedly would switch DM particle candidates to photons, in such a way as to in the end configure a photon rocket style device from DM in a thrust chamber. The presence of Dark Matter (DM) would in itself merely indicate that the emerging photon thrust would be comparatively greater than it would be for more conventional photon rockets. This amplifies and improves upon a so called axion rocket ram jet for interstellar travel. We assume that much the same sort of methodology for a would-be axion ramjet could be employed for DM, with perhaps greater thrust/power conversion efficiencies.

ZTE USA Announces Its First Corporate Partnership and Consumer Marketing Push in Conjunction with the Houston Rockets

5 October 2013, Houston--The Houston Rockets and ZTE USA, the fastest-growing smartphone provider in the United States, announced that ZTE will be the official smartphone of the Houston Rockets for the 2013-14 NBA season. This is the first partnership of its kind for ZTE globally and the first big consumer marketing push in the United States since the company entered the country 15 years ago.

Long March Rockets Complete 2018 Missions with 37 Record-Setting Launches

A LM-2D/Yuanzheng 3 launch vehicle successfully launched 6 Yunhai 2 satellites and one test microsatellite named'Chongqing'into their preset orbits,concluding China’s final orbital launch of2018.The launch took place at 16:00 Beijing time on December 29,2018 from the Jiuquan Satellite Launch Center.

A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory

How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this paper.First of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight coefficients.The Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed quantitatively.With the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed method.Finally,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%.

Rapid Launch of Medium-Sized Solid Carrier Rockets at Sea With High Reliability and Convenient Intelligence

Gravity-1 solid-propellant carrier rocket utilizes a three-vertical testing and launch mode, and adopts a sea-based launch method. As the demand for satellite launches continues to grow, the scarcity of launch site resources,and the consideration of cost savings, the need for rapid testing and launch of carrier rockets has become increasingly strong. The capability of rapid testing and launch has even become one important aspect of evaluating a rocket. This paper focuses on the characteristics of the Gravity-1 solid-propellant strap-on medium-sized carrier rocket and designs and implements a highly reliable, convenient, and intelligent low-cost rapid testing and launch solution. The main aspects include the design of a highly reliable dual-redundant ground architecture and the application of ground-based shelf products.

Derivation of a Revised Tsiolkovsky Rocket Equation That Predicts Combustion Oscillations

Our study identifies a subtle deviation from Newton’s third law in the derivation of the ideal rocket equation, also known as the Tsiolkovsky Rocket Equation (TRE). TRE can be derived using a 1D elastic collision model of the momentum exchange between the differential propellant mass element (dm) and the rocket final mass (m1), in which dm initially travels forward to collide with m1 and rebounds to exit through the exhaust nozzle with a velocity that is known as the effective exhaust velocity ve. We observe that such a model does not explain how dm was able to acquire its initial forward velocity without the support of a reactive mass traveling in the opposite direction. We show instead that the initial kinetic energy of dm is generated from dm itself by a process of self-combustion and expansion. In our ideal rocket with a single particle dm confined inside a hollow tube with one closed end, we show that the process of self-combustion and expansion of dm will result in a pair of differential particles each with a mass dm/2, and each traveling away from one another along the tube axis, from the center of combustion. These two identical particles represent the active and reactive sub-components of dm, co-generated in compliance with Newton’s third law of equal action and reaction. Building on this model, we derive a linear momentum ODE of the system, the solution of which yields what we call the Revised Tsiolkovsky Rocket Equation (RTRE). We show that RTRE has a mathematical form that is similar to TRE, with the exception of the effective exhaust velocity (ve) term. The ve term in TRE is replaced in RTRE by the average of two distinct exhaust velocities that we refer to as fast-jet, vx1, and slow-jet, vx2. These two velocities correspond, respectively, to the velocities of the detonation pressure wave that is vectored directly towards the exhaust nozzle, and the retonation wave that is initially vectored in the direction of rocket propagation, but subsequently becomes reflected from the thrust surface of the combustion chamber to exit through the exhaust nozzle with a time lag behind the detonation wave. The detonation-retonation phenomenon is supported by experimental evidence in the published literature. Finally, we use a convolution model to simulate the composite exhaust pressure wave, highlighting the frequency spectrum of the pressure perturbations that are generated by the mutual interference between the fast-jet and slow-jet components. Our analysis offers insights into the origin of combustion oscillations in rocket engines, with possible extensions beyond rocket engineering into other fields of combustion engineering.

Modeling and Validation of Thrust Prediction of Underwater Solid Rocket Motor

The solid rocket motor driven system is one of the common ways for submarines to launch underwater missiles. It has significant advantages in improving the missile’s water exit speed, anti-interference capability, and enemy striking power. The prediction of the underwater loading is a preliminary factor for the power system design of the underwater vehicle. This paper presents a rapid prediction method and validated by the experimental study for the underwater thrust of the solid rocket motor. Based on the potential flow assumption of the water field, a model of the bubble and a one-dimensional quasi-steady model of the nozzle are established to directly solve the flow status of the nozzle. The aerodynamic thrust and hydrodynamic thrust have been calculated and analyzed. The calculation results are within 5% error of the experimental results. Moreover, a design platform to predict the underwater thrust of the solid rocket motor has been developed based on Python and the PyQt library, which shows excellent system adaptability and computational efficiency.

LM-6C Carrier Rocket Makes Maiden Flight

At 11:21 on May 7,2024,the Long March 6C carrier rocket was successfully launched from China’s Taiyuan Satellite Launch Center,sending 4 satellites including Neptune 01 into their planned orbits.The launch mission was a complete success.This mission marks the maiden flight of the Long March 6C carrier rocket,signifying the addition of a new member to the Long March rocket family.It further improves China’s new generation of Long March series launch vehicles and accelerates the upgrading of China’s in-service carrier rockets.The Long March 6C carrier rocket and Neptune 01 were developed by the Shanghai Academy of Spaceflight Technology.

Identification of Backflow Vortex Instability in Rocket Engine Inducers

Bayesian estimation is applied to the analysis of backflow vortex instabilities in typical three-and four bladed liquid propellant rocket(LPR)engine inducers.The flow in the impeller eye is modeled as a set of equally intense and evenly spaced 2D axial vortices,located at the same radial distance from the axis and rotating at a fraction of the impeller speed.The circle theorem and the Bernoulli’s equation are used to predict the flow pressure in terms of the vortex number,intensity,rotational speed,and radial position.The theoretical spectra so obtained are frequency broadened to mimic the dispersion of the experimental data and parametrically fitted to the measured pressure spectra by maximum likelihood estimation with equal and independent Gaussian errors.The method is applied to three inducers,tested in water at room temperature and different loads and cavitation conditions.It successfully characterizes backflow instabilities using the signals of a single pressure transducer flush-mounted on the casing of the impeller eye,effectively by-passing the aliasing and data acquisition/reduction complexities of traditional multiple-sensor cross correlation methods.The identification returns the estimates of the model parameters and their standard errors,providing the information necessary for assessing the accuracy and statistical significance of the results.The flowrate is found to be the major factor affecting the backflow vortex instability,which,on the other hand,is rather insensitive to the occurrence of cavitation.The results are consistent with the data reported in the literature,as well as with those generated by the auxiliary models specifically developed for initializing the maximum likelihood searches and supporting the identification procedure.

China Launches Chang’e 6 Probe Atop a LM-5 Carrier Rocket

On May 3,a Long March 5 rocket carrying the Chang’e 6 probe blasted off from its launchpad at the Wenchang Space Launch Site at 17:27.The probe separated from the rocket and entered its planned transfer orbit shortly thereafter,demonstrating a completely successful launch.With the world’s attention,the Chang’e 6 probe will retrieve samples from the far side of the moon in a historic first.

China Accelerating Development of Two Large Reusable Rocket Models

BEIJING,March 12(Xinhua)——China′s development of both 4⁃meter⁃diameter and 5⁃meter⁃diameter reusable rockets is being accelerated,with their inaugural flights scheduled for 2025 and 2026,respectively.The manufacturing of these two new large reusable launching vehicle models is a response to growing demand in the commercial space market,said the China Aerospace Science and Technology Corporation.

China’s Reusable Carrier Rocket Completes First 10 km VTOL Test

On June 23,2024,China completed the first 10 km-level VTOL flight test of the reusable launch vehicle at Jiuquan Satellite Launch Center,and the test mission was a complete success.This is the largest-scale VTOL flight test of a reusable launch vehicle in China at present,and is also the first application of the deep variable thrust liquid oxygen/methane engine independently developed by China in the 10 km-level return flight,laying a solid technical foundation for achieving the maiden flight of a 4 m-level reusable launch vehicle as scheduled in 2025.

Research on Quality Assessment Method of Rocket Engine Based on Fuzzy Comprehensive Evaluation and TOPSIS Method

As the core of the rocket system,the performance and quality of rocket engines are of paramount impor-tance.Currently,the production of aerospace model rocket engines does not differentiate the production and selection of motors according to the importance of the mission,which is insufficient to ensure the high reliability requirements of important launch missions.To select rocket engines with better performance quality for more critical launch missions,this paper uses fuzzy comprehensive evaluation and TOPSIS methods based on the test value or assessment informa-tion of evaluation indicators.The method scientifically and accurately ranks the performance quality of rocket engines,choosing the engines with better performance quality for more strategic missions,and providing technical support for national management decisions.

火箭风暴:2024 Triumph Rocket 3 Storm R

2020年,凯旋推出了巨无霸“火箭三缸”Rocket 3 R,以排量高达2458mL的水平并列三缸发动机震惊世人,当仁不让地成为最大的量产摩托车。4年过去了,“火箭三缸”依然是寂寞的王者。能超越“火箭三缸”的,只有“火箭三缸”的自我进化。2024年,凯旋再次重磅出击,推出了新一代“火箭风暴”Rocket 3 Strom R,功率更大,扭矩更强,技术更先进,安全性能更好,掀起声势浩大的公路风暴!

3D打印矩形粗糙通道内火箭煤油流动换热特性试验方法研究

为探究3D打印再生冷却通道在液体火箭发动机推力室中的替代应用特性,研制了具有不同内表面粗糙度的正弦波纹结构3D打印304不锈钢矩形通道。内截面名义尺寸为2.0 mm×2.0 mm,设计粗糙度分别为6.3、25.0、100.0μm,实际粗糙度Ra分别为11.88、12.70、17.53μm,通过将高温电阻率法和像素法相结合获得了3D打印通道的实际内径和壁厚,修正了火箭煤油流动换热的内壁温和热流密度,建立了3D打印粗糙通道内火箭煤油流动换热特性试验研究方法。试验参数如下:压力处于15~20 MPa范围、质量流速在12450~24900 kg·m^(-2)·s^(-1)之间、热流密度为5~15 MW·m^(-2)、流体温度为-150℃。研究结果表明:火箭煤油流动换热特性受到热流密度、流体温度和质量流速的影响;流体温度处于50~135℃范围内,换热系数增加约25%~33%;热流密度处于5.0~15.0 MW·m^(-2)范围内,换热系数增加了8.3%;质量流速为12450~24900 kg·m^(-2)·s^(-1)范围内,换热系数增加了60.2%。粗糙度增加对火箭煤油流动换热起到强化作用,粗糙度从11.88μm增加到17.53μm时,换热强化幅度超过20%以上。该研究可为3D打印通道在火箭发动机推力室中的替代应用提供参考。

基于LabVIEW的中程制导火箭数据采集系统研究

针对中程制导火箭数据采集系统存在的被采集数据种类繁多、数据量大、易丢失、依赖人工检测及实时处理难度大等问题,设计并实现了一种基于LabVIEW的优化数据采集系统。采用面向仪器系统的外围组件互连扩展可重构技术,解决了不同型号导弹测试系统的通用性问题。在硬件配置上,选用了适宜的高速数据传输板卡,确保了数据采集的高效性和准确性。通过在FPGA模块中添加相应时标,实现了模拟信号和RS-422数据在时间维度上的精确对比。在软件开发层面,利用LabVIEW图形化编程语言开发了上位机软件,采用消息队列处理架构实施结构化编程,实现了数据的综合管理和直观显示;具备自动分析信号状态、自动生成并显示报表功能,实现了半自动化测试流程。经实验验证,该系统能够满足军工测试台的制作标准要求。