Mathematical Modeling of Induction Heating of Waveguide Path Assemblies during Induction Soldering

The waveguides used in spacecraft antenna feeders are often assembled using external couplers or flanges subject to further welding or soldering. Making permanent joints by means of induction heating has proven to be the best solution in this context. However, several physical phenomena observed in the heating zone complicate any effort to control the process of making a permanent joint by induction heating; these phenomena include flux evaporation and changes in the emissivity of the material. These processes make it difficult to measure the temperature of the heating zone by means of contactless temperature sensors. Meanwhile, contact sensors are not an option due to the high requirements regarding surface quality. Besides, such sensors take a large amount of time and human involvement to install. Thus, it is a relevant undertaking to develop mathematical models for each waveguide assembly component as well as for the entire waveguide assembly. The proposed mathematical models have been tested by experiments in kind, which have shown a great degree of consistency between model-derived estimates and experimental data. The paper also shows how to use the proposed models to test and calibrate the process of making an aluminum-alloy rectangular tube flange waveguide by induction soldering. The Russian software, SimInTech, was used in this research as the modeling environment. The approach proposed herein can significantly lower the labor and material costs of calibrating and testing the process of the induction soldering of waveguides, whether the goal is to adjust the existing process or to implement a new configuration that uses different dimensions or materials.

Identification of Problems Associated with the Usage of Friction (Koeppe) Hoists Based on Geodetic Measurements

The hoist assembly based on the Koeppe friction is a commonly used solution in mining. However, it has some disadvantages. A few centimeters offset of the groove axis can lead to excessive abrasion of linings on the Koeppe friction and pulleys. As a consequence, the mines are forced to bear the direct and indirect costs of replacing the linings such as the cost of materials and service as well as the cost of extended machine and shaft downtime. Last year, the authors undertook a geodetic inventory of the condition of two hoisting machines with a Koeppe winder. Terrestrial laser scanning enhanced with precision total station measurements were performed. Additionally, elements particularly important for the performed analysis (inclination of hoisting machine and rope wheels shafts) were determined by the precision leveling technique. Obtained results were verified using measurements on Szpetkowski’s tribrach. Appropriate selection of the measurement methods in both analyzed examples allowed us to determine the causes of destruction of each hoist assembly component. Based on precise geodetic data, guidelines have been defined for rectification (twisting and shifting the rope pulleys), which seems unavoidable despite the lack of unambiguous legal regulations.

TECHNOLOGICAL FEATURES OF PARTS WITH COMPLEX SURFACES MACHINING

The complexity of the technology of machining by cutting complex surfaces of parts heterogeneous in terms of physical and mechanical properties and different machinability, and, in particular, of metals (aluminum) and plastics (polyurethane and polyethylene), which form an assembly component, a section of the container-type countermine system is defined in the paper. The description of technological process operations of machining of a basic detail of an item, the body, is given. Features, the presence of which creates not only difficulties in the implementation of the technological process of manufacturing a base part, but is not permissible in the operation of a defense-purpose item are revealed. The article proposes design and technological solutions for the use of a new cutting tool design, capable to eliminate errors of creep feed drilling, avoid sticking of the material of the protective shell and casing on the active cutting part, exclude damage to the contact body and thereby ensure the specified performance of the item , Field tests of a container-type countermine system with basic parts manufactured using the new tool and technology have shown high efficiency of the decisions taken.

Optimization Models for Deriving Optimum Target of Key Characteristics

The aim of this research is to develop optimization models in deriving optimum target of key characteristic (KC). There are two kinds of product KCs introduced in this paper, namely performance and dimension product KC. The performance product KC target values must be determined by balancing customer and designer utilities subject to design cost and time provided by a company. The KCs of a product can be visualized using a KC flow-down which shows the hierarchical structure of the product. The flow-down may consist of many levels from product KC to process KC. Using axiomatic design as a methodology to map the flow-down, we conclude that product KC, assembly-components KC, and process KC are in functional domain, physical domain, and process domain respectively. In this paper, the objective function of the model for deriving optimum product KC target is to minimize utility gap between customer and designer subject to design cost and time. The assembly-component KCs have to be derived considering the product KC targets. In the absence of product KC target, the objective function of the model is to maximize the desired effect or minimizing the undesired effect. In the existence of product KC target, the objective function of the model is to attain the target considering technical constraints of the product. We use a shaft design problem as a numerical example to show the implementation of the models.

Applied Technology of Customizable Architecture for 3D Graphics Render Engine Platform

In order to avoid the flaw including rigid regulations of architecture, strong coupling among modules, removal of fault and advanced technology embedding hard in 3D graphics render engine, a customizable architecture for 3D graphics render engine platform was proposed. The architecture introduced some simulation models which were design standard, expansibility, assembly relation of simulation component resource, development of typical modules and component design. Application developer could customize simulation assembly component flexibly and compose own 3D graphics render engine generally.

Generic Simulation of an Automated Assembly

System design generally involves making long-term decisions such as facility layout and system capacity/configuration. As such, models are typically created and used for a single design exercise, and model run time is not a significant factor during the simulation process. The simulation process is based on the use of Simio standard simulation program. This chapter comprises of a generic workstation diagram that shows a setup of an ideal assembly line. This assembly diagram is the basis from which a flowchart/ algorithm is derived from. The assembly line consists of workstations (one to some given number N). N in case is six. Each workstation is fed by buffer storage areas which are continuously replenished according to the supply conditions of the program. A transporter transports the assembly in between stations. This transporter can either be a conveyor as is with Arena, or a vehicle, as is the case in the Simio program. The Generic Flowchart is based on the Generic Assembly Diagram. The given steps from the identification of the component to has the component has been assembled? occur in one assembler and are for one component. These activities (flowchart) are repeated for each component up to the required number of components that make-up the product, i.e. the loops are repeated for each component in the assembly process. The purpose of this paper is to establish a generic simulation process, which will be based on the generic algorithm and generic assumptions to be used to simulate an automated assembly process. In this generic program, the following parameters can be varied: number of workstations, number of components, and order of assembly, cycle time, time to assembly, component and workstation availability and buffer capacity.