Search results

The purpose of this paper is to design a special automatic redundant robot painting system (RRPS), which can automatically navigate and paint in the long non-regular duct.

The RRPS is designed with three subsystems: a redundant robot, a spraying system and a control and safety system. Based on the modular design theory, the robot falls naturally into a mobile platform, a 4-DOF location mechanism and a 10-DOF manipulator. The restriction of the distance between the links and the duct axis is used to plan the trajectory of the manipulator so that it would not collide with the duct. The restriction model is constructed by minimizing the sum of the weighed distances between the duct axis and the special points.

A fully working prototype system has been developed. Test results show that the minimal distance between the robot joints and duct is 18 mm, and it can finish painting long non-regular ducts at the speed of 12.5 cm/s and the spraying distance of 16 cm. The quality of coating layers is good.

The RRPS was used to paint non-regular rectangular ducts, cylindrical ducts and long non-regular ducts. The feasibility of painting long non-regular duct is proved with the prototype implementation and successful test results.

The RRPS shows a novel solution that is based on the 14-DOF redundant robot design for painting long non-regular ducts which is used in airplane.

The purpose of this paper is to present a novel laser pointer for manual coating robot teaching. The laser pointer has simple structure and no physical contact with substrate in teaching work. The sensitivity of visual detection in the design accuracy is guaranteed.

The strategy adopts two laser sources to form a triangle to achieve a fixed distance detection pointer for manual robot teaching. After optimizing the source, spot size and the incident angle of the lasers, the sensitivity of fixed-distance judgment is analyzed and compared with traditional pointers. In addition, the laser pointer adds the functions to simulate coating atomizer, including posture and overlap pitch. Finally, the laser pointer verified by coating application and measurement system analysis evaluation.

The laser pointer has been successfully applied to coating robot teaching by the authors’ team. From the simulation and experimental results, it can be concluded that the proposed approach is effective at improving manual teaching of coating robot, especially for the complex geometry.

The main function of the laser pointer often used for manual teaching in other purposes; for example, sealer etc. The paper innovatively considered and tested the laser pointer on robotic coating process.

Compared with the traditional hard straight stick pointer, the paper proposes a very simple construction for teaching pointer with laser feature. At the same time, the requirement of coating process simulation is considered.

The purposes of this paper are to review the progress of and conclude the trend for paint thickness simulation for painting robot trajectory planning.

This paper compares the explicit function-based method and computational fluid dynamics (CFD)-based method used for paint thickness simulation. Previous research is considered, and conclusions with the outlook are drawn.

The CFD-based paint deposition simulation is the trend for paint thickness simulation for painting robot trajectory planning. However, the calculation of paint thickness resulting from dynamically painting complex surface remains to be researched, which needs to build an appropriate CFD model, study approaches to dynamic painting simulation and investigate the simulation with continuously changing painting parameters.

This paper illustrates that the CFD-based method is the trend for the paint thickness simulation for painting robot trajectory planning. Current studies have been analyzed, and techniques of CFD modeling have also been summarized, which is vital for future study.

Employment Characteristics of Older Women. This is the title of an article by Diane E. Herz in the September 1988 issue of Monthly Labor Review. It examines the employment characteristics of older women in America in 1987.

This paper aims to investigate the heat transfer in porous channels.

Finite element method is used to simulate the heat transfer in porous channels.

The number and width of channels play a key role in determining the heat transfer of the porous channel. The heat transfer is higher around the channel legs. Smaller base height is better to get higher heat transfer capability.

This study represents the original work to investigate heat transfer in a porous domain having multiple channels.

The primary purpose of this paper is the development of a fire–structure interface (FSI) model, which is referred in this study as a simplified “dual-layer” model. It is oriented for design purposes, in the cases where fire-compartments exceed the “regular” dimensions, as they are defined by the guidelines of the codes (EN 1991-1-2).

The model can be used at the post-processing stage of computational fluid dynamics (CFD) analysis and it is based on the gas-temperature field (spatial and temporal) of the fire-compartment. To use the “dual-layer” model, first the gas-temperature (discrete) function along the height of the fire-compartment, at discrete plan–view points should be determined through the output of the CFD analysis. The model “compresses” the point data to (spatial) virtual zones, which are divided into two layers (with respect to the height of the fire-compartment) of uniform temperature: the upper (hot) layer and the lower (cold) layer.

The model calculates the temporal evolution of the gas-temperature in the fire compartment in every virtual zone which is divided in two layers (hot and cold layer).

The main advantage of this methodology is that actually only three different variables (height of interface upper-layer temperature and lower-layer temperature) are exported during the post-processing stage of the CFD analysis, for every virtual zone. Next, the gas-temperature can be used for the determination of the temperature profile of structural members using simple models that are proposed in EN 1993-1-2.

PLAIN, slide‐surface bearings were used right at the start of engineering practice, in the form of simple bushes. Whereas there is nowadays a very wide selection of bearings of more sophisticated types, it is a fact that sliding surface bearings are still employed extensively in many modern and exacting applications. The forms have, however, changed drastically over the years, and no longer is the sliding‐surface bearing limited in application to supporting properly aligned shafts under conditions where lubricant can be directed in copious amounts to the friction surfaces. The modern counterpart of the simple bush can be of spherical‐seating type if required, for accommodating shaft misalignment, and may be manufactured from so‐called ‘self‐lubricating’ materials.

This study aims to numerically study the buoyant convective flow of two different nanofluids in a porous annular domain. A uniformly heated inner cylinder, cooled outer cylindrical boundary and adiabatic horizontal surfaces are considered because of many industrial applications of this geometry. The analysis also addresses the comparative study of different porous media models governing fluid flow and heat transport.

The finite difference method has been used in the current simulation work to obtain the numerical solution of coupled partial differential equations. In particular, the alternating direction implicit method is used for solving transient equations, and the successive line over relaxation iterative method is used to solve time-independent equation by choosing an optimum value for relaxation parameter. Simpson’s rule is adopted to estimate average Nusselt number involving numerical integration. Various grid sensitivity checks have been performed to assess the sufficiency of grid size to obtain accurate results. In this analysis, a general porous media model has been considered, and a comparative study between three different models has been investigated.

Numerical simulations are performed for different combinations of the control parameters and interesting results are obtained. It has been found that the an increase in Darcy and Rayleigh numbers enhances the thermal transport rate and strengthens the nanofluid movement in porous annulus. Also, higher flow circulation rate and thermal transport has been detected for Darcy model as compared to non-Darcy models. Thermal mixing could be enhanced by considering a non-Darcy model.

The present results could be effectively used in many practical applications under the limiting conditions of two-dimensionality and axi-symmetry conditions. The only drawback of the current study is it does not include the three-dimensional effects.

The results could be used as a first-hand information for the design of any thermal systems. This will help the design engineer to have fewer trial-and-run cases for the new design.

A pioneering numerical investigation on the buoyant convective flow of two different nanofluids in an annular porous domain has been carried out by using a general Darcy–Brinkman–Forchheimer model to govern fluid flow in porous matrix. The results obtained from current investigation are novel and original, with numerous practical applications of nanofluid saturated porous annular enclosure in the modern industry.

Concerns a study by Manchester City Transport (MCT) which attempts to break away from conventional methodology involving merely traffic engineering and cost of reduction schemes. Indicates that even for an area predominantly populated by business executives, a significant demand can exist for public transport innovations, specifically designed to meet consumer needs. Represents part of a wider marketing study sponsored by MCT. Concludes that this study has thrown some light on to those and other questions, but as it has already been recognised, time and financial constraints have limited its scope.