Dynamic Interaction between Manipulator and Omni-Directional Platform

Recent advancements in mechatronics has led to tremendous development of application of robots for industrial applications involving high health hazards, rough working conditions and difficult to reach locations. Robot assisted welding is one such high risk operation for human being. The industrial arc welding robots are either mounted on the floor, table or on overhead rails. In this scenario, the jobs to be welded are brought to shop floor. However, the on-sight joining of big pipes and structures with precision and speed, demands for mobility of welding robot. In this research work, a novel concept of mounting 5-dof welding robot on the omni-directional platform (Omni-WMR) is implemented to provides immense maneuvering mobility to the manipulator. This paper presents the combined dynamic model of omnidirectional mobile robot for welding operation to study the effect of dynamic interaction between manipulator and mobile platform. Dynamic interaction is carried out to find the variation in torque at manipulator link due to the motion of platform as well as its location on the platform. In addition, the variation in torque developed at platform wheels due to positioning the manipulator at two different locations on platform is accessed. For this, two case studies have been discussed to study the effect of dynamic interaction between manipulator and omni-directional platform.

OPTIMIZATION OF EDM PARAMETERS USING INTEGRATED APPROACH OF RSM, GRA AND ENTROPY METHOD

This paper presents a hybrid optimization approach for the determination of the optimal process parameters which maximize the material removal rate and minimize surface roughness & the tool wear rate. The input parameters of electrical discharge machining considered for this analysis are pulse current (Ip), pulse duration (Ton) & pulse off time (Toff). The influences of these parameters have been optimized by multi response analysis. The designed experimental results are used in the gray relational analysis & the weight of the quality characteristics are determined by the entropy measurement method. The effects of the parameters on the responses were evaluated by response surface methodology, which is based on optimization results. On the basis of optimization results it has been found that pulse current (Ip) of 5A, a pulse duration (Ton) of 60μs & pulse off time (Toff) 45μs, which are the best combination of this analysis.

FORMULATION OF MATHEMATICAL MODEL FOR MAINTENANCE COST OF A STONE CRUSHING PLANT BASED ON DIMENSIONAL ANALYSIS AND MULTIPLE REGRESSION

This paper presents the approach for the mathematical modeling of maintenance cost for the set up of new Stone Crushing Plant based on the dimensional analysis and multiple regression. Presented maintenance cost mathematical model is derived based on the generated design data. Design data is generated from actual design of all stone crushing plants followed by static and dynamic analysis. Estimation of design data is carried out based on the assumed plant layout. Dimensional analysis is used to make the independent and dependent variables dimensionless and to get dimensionless equation. Later, multiple regression analysis is applied to this dimensionless equation to obtain the index values based on the least square method. The mathematical model of maintenance cost is formulated using these obtained index values. Finally, the formulated model is evaluated on the basis of correlation and root mean square error between the computed values by model and the estimated values.

TARGET HIT INTERCEPTOR MID-COURSE GUIDANCE SCHEME FOR BALLISTIC MISSILE INTERCEPTION

A Mid-course guidance algorithm has been developed for an exo-atmospheric interceptor to neutralize an incoming high speed ballistic Target. The guidance scheme positions the interceptor ahead of the target so that the velocity vectors of the target and interceptors are in the same direction. As the interceptors used in ballistic missile defence have a lower velocity than the incoming target, the target approaches the interceptor. The guidance scheme reduces the closing velocity compared to a head on approach thereby increasing the homing time for a given terminal sensor detection range. The guidance law is validated through numerical simulation.

ANALYTICAL MODELING OF PLANETARY GEAR AND SENSITIVITY OF NATURAL FREQUENCIES

This work develops an analytical model of planetary gears and uses it to investigate their natural frequencies and vibration modes. The model admits three planar degrees of freedom for each of the sun, ring, carrier and planets. Vibration modes are classified into rotational, translational and planet modes. The natural frequency sensitivities to system parameters are investigated for tuned (cyclically symmetric) planetary gears. Parameters under consideration include support and mesh stiffnesses, component masses, and moments of inertia. Using the well-defined vibration mode properties of tuned planetary gears, the eigen sensitivities are calculated and expressed in simple exact formulae. These formulae connect natural frequency sensitivity with the modal strain or kinetic energy and provide efficient means to determine the sensitivity to all stiffness and inertia parameters by inspection of the modal energy distribution.

MULTI-OBJECTIVE OPTIMIZATION FOR DESIGN OF SINGLE ROW LAYOUT IN FLEXIBLE MANUFACTURING SYSTEM WITH SCHEDULING CONSTRAINT:AN APPROACH OF NONTRADITIONAL OPTIMIZATION TECHNIQUES

Single row layout is one of the most usually used layout patterns in industries, particularly in flexible manufacturing systems. Here actual sequencing of machine and arrangement of parts, no doubt, have a great influence on the throughput of the flexible manufacturing system i.e., (F.M.S). This paper discusses the single row layout design in flexible manufacturing system (F.M.S). This paper furnishes the design, development and testing of simulated annealing technique and genetic algorithm to solve the single row layout problem by considering multi-objective i.e., minimizing the make span of jobs on all machines and minimizing the total transportation cost. The various line layout problems are tested for performance of objective function with respect to computational time and number of iterations involved in GA and SA. A necessary code is generated in C++ and the code is run by the IDE tool in which C++ compiler used as plug in. This tool has Eclipse based features which affords the competency to figure, correct, steer, and sort out the tasks that use C++ as a programming language using Intel core i3-380M processor. The results of the different optimization algorithms (Genetic Algorithm and simulated annealing method) are compared and finally, we observed that GA provide optimum results than SA.

An Intelligent Permeability Optimization System at Sinter Plant of Rourkela Steel Plant

The permeability of sinter mix is one of the vital parameters that affect the performance of sintering process. The amount of water added in the granulation drum has a significant effect on the permeability of the sinter bed and sinter machine productivity. Considering the variation in input feed materials and the parabolic nature of permeability-moisture curve, the optimum level of water addition is a difficult task for the operator to determine. Therefore a mathematical model based intelligent permeability measurement system is developed which determine the required amount of water to be added in granulation drum to achieve the optimum permeability based on the given input material.

HEAT TRANSFER ENHANCEMENT USING DIFFERENT GEOMETRY OF TWIST TAPE TURBULATORS: A REVIEW

The development of high-performance thermal systems has increased interest in heat transfer enhancement techniques. The high thermal performance enhancement of heat exchanger systems is needed to use energy source efficiently due to the sky-rocketing prices of petroleum and coal fuels. Heat exchangers are widely used in industry both for cooling and heating. Insertion of turbulators in the flow passage is one of the favorable passive heat transfer augmentation techniques due to their advantages of easy fabrication, operation as well as low maintenance. The purpose of this review presents the effect of twisted tape turbulators on the heat transfer enhancement, pressure drop, flow friction and thermal performance factor characteristics in a heat exchanger tube. The twisted tape turbulator is a device for increasing the heat transfer rate in the heat exchanger system. The widely employed in several industrial and engineering applications of heat exchanger are automobile, refrigerators, solar collector, heat engine, air conditions, thermal power plant, electronic cooling, milk plant, chemical process industries etc. heat transfer enhancement using different type of the turbulators placed in the tube has been extensively studied for the past decade among the both passive and active technique are compile in this review.

VIBRATION ANALYSIS OF PLANETARY GEAR SYSTEM

In this work a dynamic model of a planetary gear transmission is developed to study the sensitivity of the natural frequencies and vibration modes to system parameters in perturbed situation. Parameters under consideration include component masses ,moment of inertia , mesh and support stiff nesses .The model admits three planar degree of freedom for planets ,sun, ring, and carrier. Vibration modes are classified into translational, rotational and planet modes .Well-defined modal properties of tuned (cyclically symmetric) planetary gears for linear ,time-invariant case are used to calculate eigensensitivities and express them in simple formulae .These formulae provide efficient mean to determine the sensitivity to stiffness ,mass and inertia parameters in perturbed situation.

EVALUATION OF S.I.F FOR CRACK EMANATING AT 450 ORIENTATION FROM A HOLE IN PRESSURISED CYLINDER USING FEA

The use of fracture mechanics techniques combining with Finite Element Analysis [F.E.A] in assessment of performance and reliability of pressure vessel structure is on demand .The machine elements with cylindrical profile such as cylindrical shells, which are used extensively as the structural configuration in aerospace and shipping industries needs to be leak proof. But during their service life, a crack may initiate on internal/external boundary of circular cylinder which influences on stress distribution in the structure. All flaws in a physical structure may not always have the same orientation relative to boundaries and material interfaces. In fracture mechanics, Stress Intensity Factor (SIF) is an important criterion to evaluate the impact of crack as the magnitude of SIF determines the propagation of crack. This paper reviews on investigation of S.I.F for 45 deg arbitrarily oriented flaw emanating from a hole in pressurised cylinder using Displacement Extrapolation Method (DEM) in F.E.M that would aid in the determination of the critical nature of such flaws.