Mobile Launch Research Articles

Qualification of a Wankel Rotary Engine for UAV Application - Airworthiness Challenges

An indigenous Wankel Rotary Engine of 40 kW class has been developed for Unmanned Aerial Vehicle (UAV) application. It should be capable of flying flawlessly for long duration at designated altitude and carrying the payload intended for the mission. The engine has to withstand high shock loads during launching from a mobile launcher and has to climb to the designated altitude within a specified time. To meet these requirements the engine needs to deliver required power while operating at its maximum speed during take-off and climb. Therefore qualification of a Wankel rotary engine for this type of application is a great challenge and needs thorough study of its component durability and engine performance and reliability. This paper presents the various qualification tests stipulated on the components, systems and on engine to establish its performance, integrity and reliability. The paper also highlights the basis of clearing the engine for its first flight. Engine made its maiden flight successfully on an UAV platform exhibiting satisfactory performance.

Improving the efficiency of last-mile delivery with the flexible drones traveling salesman problem

This paper analyzes how last-mile delivery performance can be improved based on combining one truck and multiple drones. We propose a Flexible Drones Traveling Salesman Problem (FDTSP) model to minimize the total delivery time. In FDTSP, a truck acts as a mobile launch platform for drones, delivers parcels to customers, and replaces drone deliveries when necessary, while drones distribute parcels to as many customers as possible to minimize the time spent on the whole route. To solve the FDTSP, we prose a two-stage heuristic formulated on bisecting K-means and metaheuristics approaches. Alternative delivery solutions for exceptional customer nodes, which exceed the drone endurance, are also introduced to ensure the deliveries for all customers in the network. The comparison analysis of three algorithms is also examined. The FDTSP significantly achieves time saving between 7.13% and 24.17% and improves the on-time service level between 13.01% and 19.77% compared to the truck-only mode. The number of customers served by drones can increase up to 56.47% if using one drone; however, additional drones may have declining marginal returns. The FDTSP reduces total tour time for last-mile delivery in urban areas with a high density of customers. Additionally, the longer the drone endurance and the faster the drone speed, the higher the efficiency of the FDTSP.

Node topology location method of SDN social network based on ant colony algorithm

Due to the convergence defect of the existing SDN social network node topology location methods, there is a large node topology location error problem. In order to solve the above problems, this paper proposes a topology location method of SDN social network nodes based on ant colony algorithm. Firstly, the ant colony algorithm is introduced, and then the biological principle of ant colony algorithm is analyzed to determine the basic steps of ant colony algorithm. According to the number of mobile beacon launch positions and specific launch coordinates in ROI, ant colony algorithm is introduced into the mobile beacon path acquisition program to realize SDN node topology location based on ant colony algorithm. The experimental results show that under the background of node communication radius of 2.0 and 5.0, the node topology positioning errors of this method are small, and the minimum errors are 9.10% and 5.15% respectively. It is fully proved that this method has good node topology positioning effect.

Electromagnetic threat faced by mobile launch rocket and simulation construction of test electromagnetic environment

Under the condition of informatization, the system efficiency will be seriously challenged by the intervention of opponents in the electromagnetic field. With the complexity of the electromagnetic environment in the future, the types of electromagnetic threats faced by mobile launch rockets are increasing. The adaptability to the complex electromagnetic environment has become the key factor whether they can complete the launch mission as planned. Taking the mobile launch rocket as the research object, this paper analyzes the main electromagnetic threats faced by it, such as electronic reconnaissance, electronic jamming, electronic destruction and precision strike, and puts forward the basic scheme of electromagnetic threat environment simulation required for relevant electromagnetic environment adaptability test. The research has direct guiding value for testing the electromagnetic threat response ability of mobile launch rocket and promoting its application and efficiency in complex electromagnetic environment.

Prospects for using mobile launching sites in hail suppression operations

The paper describes the reasons underlying the development of the concept of mobile launching sites for hail suppression operations. The main disadvantages of using fixed launching sites in hail protection network at the present time are enumerated. Possible variants of the method of using mobile launching sites are proposed. The main tactical and technical characteristics of the mobile launching site are given.

A Study of a Mobile Launch Platform Effect on Bi-folded Wing Deployment

A Study of a Mobile Launch Platform Effect on Bi-folded Wing Deployment

The Investigation of Fire Effects to Structural Elements of a Mobile Unit with a Compact Nuclear Power Plant

During the first twenty years of the ХХI century a number of a different nature armed conflicts have occurred. In some of them states with nuclear-missile take part. The article researches one of the phases of emergency situation growth driven by fire generated conventional weapon on the mobile launch platform with solid-propellant ballistic missile. The simulation of the thermal effect on air frame and transporter-launcher container is performed, the result calculation valuation and experiment are carried out.

Synchronized Truck and Drone Routing in Package Delivery Logistics

The use of Unmanned Aerial Vehicles (UAVs) in delivery logistics has become an efficient solution with the advancement of autonomous robotics. This paper proposes a novel mechanism that synchronizes drones and delivery trucks; particularly the case where trucks can work as mobile launching and retrieval sites. The problem is a Vehicle Routing Problem with Time Windows and Synchronized Drones. A multi-objective optimization model is developed with two conflicting objectives, minimizing the travel costs and maximizing the customer service level in terms of timely deliveries. A novel Collaborative Pareto Ant Colony Optimization algorithm is proposed to solve the model and Non-dominated Sorting Genetic Algorithm II (NSGA-II) is used to compare and validate the proposed algorithm. The experimental results indicate that the proposed mechanism is an efficient solution to parcel delivery logistics.

Internal ballistic simulation and optimum design of gas-fired rodless cylinder ejection device

A kind of gas-fired rodless cylinder ejection device which is stoke and weight controlled and suitable for mobile launch was designed. The leakage test of the ejection device is carried out based on the principle prototype of rodless cylinder ejection device and the empirical formula between leakage rate and pressure and travel length was fitted. The mathematical model of gas-fired rodless cylinder ejector internal ballistic with considering the leakage rate is established based on the assumption of zero-dimensional internal ballistic. When comparing the results of internal ballistics considering and not considering the leakage rate, it can be seen that the influence of leakage rate on the results of internal ballistics can not be ignored. The internal ballistic model which coupled the leakage rate is optimized, taking the shortest design stroke and smallest ejection stability index as design target and the parameters of the grain are used as design variables. The results show that after the optimization, the mass flow rate of gas at the end of ejection is increased by 19%, the stroke required for piston speed reaching the design target is shortened by 13.1%, and the launch stability index is increased by 10.7%.

Математическая модель движения ракеты относительно подвижной пусковой установки

Математическая модель движения ракеты относительно подвижной пусковой установки

Guidance Systematic Error Separation for Mobile Launch Vehicles Using Artificial Fish Swarm Algorithm

For missile’s accuracy assessment, an accurate separation about the guidance of systematic errors is a critical part. Based on the vehicles from a mobile launcher platform, this paper proposes a nonlinear error separation model and a corresponding method in consideration of the ill-conditioning of the environmental function matrix, and the coupling of the guidance instrumental errors and the initial errors. The nonlinear model is built in combination with the tracking data. For the error separation problem with ill-conditioning, the traditional nonlinear methods can only slightly weaken the degree of ill-conditioning rather than solve it. To address this issue, this paper puts forward a novel guidance systematic error separation method based on the artificial fish swarm algorithm (AFSA). We first provide a brief introduction to AFSA and then analyze the convergence and the optimality of parameter estimation. Furthermore, we present the details of our novel algorithm that can address the guidance systematic error separation problem. We conduct a set of simulations to verify our approach. The simulation results confirm that our approach, which is based on AFSA, can improve the error separation accuracy effectively and perform better than the Bayesian estimation based on the traditional linear model and the Bayesian maximum a posteriori estimation based on the nonlinear model.

Development and Testing of Nano-Clay Composites for Pressure Pad Application

Pressure pads are used in mobile cranes and launch vehicles to distribute the reaction forces uniformly on the soil. In mobile cranes these pressure pads made on alloy steel and permanently fixed below the elephant foot through ball and socket joint. Launch vehicles are used to carry and outrigger the missiles in operating field or war field. Load distribution during the outrigger will be challenging in uneven ground surfaces and loose soils. Pressure pads add the flexibility in outriggering the missiles even in a loose soil with ground pressure of 4kg/cm2. Considering the place of application, detachable type pressure pads are used in launch vehicles. Aluminium alloy is preferred over the steel due to its less weight and easy handling. In this research study nano-clay epoxy composites are proposed as an alternate material for pressure pads of launch vehicles due to its high compression load and strength to weight ratio. The present study focused on the preparation of nano-clay epoxy composites and neat epoxy composites. The work further analyzed the deflection of composites during forward and reverse loading. Creep test was also conducted for a period of 4 hours. The test results revealed that the nano-clay composites were bearing more compressive strength with lesser weight than neat resin composites.

Geometric model of mobile device to launch unmanned aerial vehicles

A geometric model of the trebuchet-type mobile metal launching device, designed for launch (catapult) of small unmanned aerial vehicles, is developed. Structurally, the launch mechanism is coupled with a car that facilitates its mobility. In addition, the car itself is used as a counterweight in the trebuchet design. The calculations of the motion of the launch mechanism are made using the Lagrange equations of the second kind. The test calculations are given

Метод определения типов и значений параметров накопителя электрической энергии при его работе в составе системы автономного электроснабжения мобильного ракетного стартового комплекса

Метод определения типов и значений параметров накопителя электрической энергии при его работе в составе системы автономного электроснабжения мобильного ракетного стартового комплекса

The Royal Australian Navy’s Landing Helicopter Docks: a missile carrier concept

ABSTRACTThis paper examines the feasibility of launching Terminal High Altitude Area Defense (THAAD) Ballistic Missile Defense (BMD) interceptors from the Royal Australian Navy’s (RAN) Landing Helicopter Dock (LHD) flight decks. Repurposing the LHDs as a kind of ‘Missile Carrier’ would exploit the ships flexible space, and the road-mobile architecture of THAAD. Advantages include: enhanced protection for deployed Australian forces; unlimited magazine depth and a common tri-service theatre BMD capability. Challenges include: space and weight restrictions of the LHDs elevators; hazards caused by electromagnetic radiation and missile back-blast plus the potential instability of THAAD launchers in strong crosswinds or high sea states. This paper concludes that, with the right investments, it appears technically possible to use the LHDs as mobile THAAD launch platforms. Areas not within the scope of this paper provide fertile ground for future research into the political, diplomatic and budgetary dimensions of a THAAD missile carrier concept.

Acoustic signature characterization of a sub-scale rocket launch

Georgia Tech Research Institute (GTRI) conducted a flight test of a sub-scale rocket in 2013 outside Talladega, Alabama, to acquire the launch acoustics produced. The primary objective of the test was to characterize the acquired data during a sub-scale launch and compare it with heritage launch data from the STS-1 Space Shuttle flight. Neither launch included acoustic suppression; however, there were differences in the ground geometry. STS-1 launched from the Mobile Launch Platform at Pad 39B with the RS-25 liquid engines and Solid Rocket Boosters (SRBs) firing into their respective exhaust ducts and flame trench, while the GTRI flight test vehicle launched from a flat reflective surface. The GTRI launch vehicle used a properly scaled Solid Rocket Motor (SRM) for propellant; therefore, primary analysis will focus on SRM/SRB centric acoustic events. Differences in the Ignition Overpressure (IOP) wave signature between both due to this will be addressed. Additionally, the classic liftoff acoustics “football shape” is preserved between both full and sub-scale flights. The launch signatures will be compared, with note taken of specific launch acoustic events more easily investigated with sub-scale launch data or supplement current sub-scale static hotfire testing.

Mobile Money: The Opportunity for India

The full potential of digital financial services in India has not yet been realised. Millions of people still lack a viable alternative to the cash economy and informal financial services, and mobile money represents a great opportunity for the country. For mobile network operators (MNOs), launching and scaling services for the unbanked has proved very challenging because of several regulatory barriers. This paper provides evidence of the benefits and the business case for mobile money for Indian MNOs, and proposes a set of regulatory reforms that would clear the way for viable and sustainable mobile money deployments, driving financial inclusion, improving financial stability and integrity, protecting financial consumers, and guarding the financial system against the risks of the widespread use of cash. The key tenets of enabling mobile money regulation are: a) allowing a business model that safeguards customer money stored in the system and preserves financial stability; b) proportional (risk-based) anti-money laundering and combating the financing of terrorism (AML/CFT) regulations and promoting tiered know-your-customer (KYC) procedures; and c) putting cost-effective regulatory solutions in place to set up and manage distribution networks and accelerate customer adoption. This paper was formally submitted to the Reserve Bank of India (RBI) by the Mobile Money Association of India (MMAI) and the GSMA with the aim to outline reforms that would enable innovation in mobile financial services and build a stable, inclusive, secure, and efficient financial sector.

Numerical Analysis of Ignition Overpressure Effect on H-IIB Launch Vehicle

A numerical simulation was conducted to investigate the ignition overpressure mechanism generated by the Japanese H-IIB launch vehicle. A simplified benchmark problem and analysis of a free jet exhausted from a single solid booster were used to verify the present numerical method; the unsteady Reynolds-averaged Navier–Stokes simulation was found to be essential for determining the typical features of ignition overpressure, such as the shock wave generated in front of the plume and following starting vortex. Comparing with the measured pressure history at the launch complex, the numerical result agreed reasonably. The correlation between the wave pattern measured at the launch complex and the ignition overpressure mechanism was clarified. The effect of ignition overpressure on the launch vehicle can be reduced by shielding the inlet of the flame duct with a mobile launcher; however, severe impact on the launch complex is unavoidable. The numerical technique and knowledge obtained in this study are applicable in the preliminary design of a launch pad to mitigate the impact of ignition overpressure.

Scale model thruster acoustic measurement results

The Space Launch System (SLS) Scale Model Acoustic Test (SMAT) is a 5% scale representation of the SLS vehicle, mobile launcher, tower, and launch pad trench. The SLS launch propulsion system will be comprised of the Rocket Assisted Take-Off (RATO) motors representing the solid boosters and four Gas Hydrogen (GH2) thrusters representing the core engines. The GH2 thrusters were tested in a horizontal configuration in order to characterize their performance. In phase 1, a single thruster was fired to determine the engine performance parameters necessary for scaling a single engine. A cluster configuration, consisting of the four thrusters, was tested in phase 2 to integrate the system and determine their combined performance. Acoustic and overpressure data was collected during both test phases in order to characterize the system’s acoustic performance. The results from the single thruster and 4-thuster system are discussed and compared.

Scale model acoustic test overview

Launch environments, such as lift-off acoustic (LOA) and ignition overpressure (IOP), are important design factors for any vehicle and are dependent upon the design of both the vehicle and the ground systems. LOA environments are used directly in the development of vehicle vibro-acoustic environments and IOP is used in the loads assessment. The Scale Model Acoustic Test (SMAT) program was implemented to verify the Space Launch Systems LOA and IOP environments for the vehicle and ground systems including the Mobile Launcher (ML) and tower. The SMAT is currently in the design and fabrication phase. The SMAT program is described in this presentation.