Tool accessibility with path and motion planning for robotic drilling and riveting

Robotic applications in aerospace manufacturing and aircraft assembly today are limited. This is because most of the aircraft parts are relatively small or have complex shapes that make tasks like robotic drilling and riveting more challenging. These challenges include tool accessibility, path planning, and motion planning. In this thesis, a process methodology was developed to overcome the tool accessibility challenges facing robotic drilling and riveting for aircraft parts. The tool accessibility was analyzed based on the Global Accessibility Area and the Global Accessibility Volume to determine the accessible boundaries for parts with zero, one and two surfaces curvatures. The path planning was optimized based on the shortest distance, least number of steps, and minimal tool orientation change. The motion planning was optimized based on the s-curve using the robot’s maximum velocity and acceleration for minimum cycle time and maximum production rate. A software application was developed to simulate the tasks.

Tool accessibility with path and motion planning for robotic drilling and riveting

Robotic applications in aerospace manufacturing and aircraft assembly today are limited. This is because most of the aircraft parts are relatively small or have complex shapes that make tasks like robotic drilling and riveting more challenging. These challenges include tool accessibility, path planning, and motion planning. In this thesis, a process methodology was developed to overcome the tool accessibility challenges facing robotic drilling and riveting for aircraft parts. The tool accessibility was analyzed based on the Global Accessibility Area and the Global Accessibility Volume to determine the accessible boundaries for parts with zero, one and two surfaces curvatures. The path planning was optimized based on the shortest distance, least number of steps, and minimal tool orientation change. The motion planning was optimized based on the s-curve using the robot’s maximum velocity and acceleration for minimum cycle time and maximum production rate. A software application was developed to simulate the tasks.

Optimal Fixed Bed Reactor Network Configuration for the Efficient Recycling of CO2 into Methanol

An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.

Optimal Fixed Bed Reactor Network Configuration for the Efficient Recycling of CO2 into Methanol

An optimal design strategy of a network of fixed bed reactors for Methanol Production (MP) is proposed in this study. Both methanol production and profit spanning a production period of eight years have been set as objective functions to find the optimal production network. The conservation of mass and energy laws on a heterogeneous model of a single industrial methanol reactor was first developed. The model was solved numerically and was validated with industrial plant data. Different reactor network arrangements were then simulated in order to find an optimal superstructure. It was found that a structure of four reactors (two in series in parallel with another two in series) provide maximum production rate. The application of the more realistic objective function of profit showed that a configuration of two parallel reactors is the best configuration. This optimal structure produces 92 tons/day more methanol than a single reactor.

System dynamics model of production-inventory-routing system in the green supply chain

Fierce competition in the global markets forced companies to improve the design and management of supply chains, because companies are always looking for more profit and higher customer satisfaction. The emergence of the green supply chain is one of the most important developments of the last decade. It provides an opportunity for companies to adjust their supply chains according to environmental goals and sustainability. The integrated production-inventory-routing is a new field that aims to optimize these three decision-making levels. It can be described as follow: a factory produces one or more products, and sells them to several customers (by direct delivery or a specific customer chain). The current study aims to model a production-inventory-routing system using a system dynamics approach to design a green supply chain under uncertain conditions. For this purpose, first, the association between selected variables was determined. Then, the proposed model was validated. Finally, to identify variables with the highest influence, four scenarios were developed. The results indicated that minimum total transportation cost, the total warehouse capacity of the supply chain, and the maximum production rate are the most influential strategies to achieve ideal condition.

Platinum Based Nanoparticles Produced by a Pulsed Spark Discharge as a Promising Material for Gas Sensors

We have applied spark ablation technology for producing nanoparticles from platinum ingots (purity of 99.97 wt. %) as a feed material by using air as a carrier gas. A maximum production rate of about 400 mg/h was achieved with an energy per pulse of 0.5 J and a pulse repetition rate of 250 Hz. The synthesized nanomaterial, composed of an amorphous platinum oxide PtO (83 wt. %) and a crystalline metallic platinum (17 wt. %), was used for formulating functional colloidal ink. Annealing of the deposited ink at 750 °C resulted in the formation of a polycrystalline material comprising 99.7 wt. % of platinum. To demonstrate the possibility of application of the formulated ink in printed electronics, we have patterned conductive lines and microheaters on alumina substrates and 20 μm thick low-temperature co-fired ceramic (LTCC) membranes with the use of aerosol jet printing technology. The power consumption of microheaters fabricated on LTCC membranes was found to be about 140 mW at a temperature of the hot part of 500 °C, thus allowing one to consider these structures as promising micro-hotplates for metal oxide semiconductor (MOS) gas sensors. The catalytic activity of the synthesized nanoparticles was demonstrated by measuring the resistance transients of the non-sintered microheaters upon exposure to 2500 ppm of hydrogen.

Step-drawdown tests in exploitation wells for thermal and mineral water – Case study from Slovenia

A comparative analysis of step-drawdown tests was performed in order to estimate the well performance in Slovenian thermal and mineral water wells. Tests were performed in 30 wells, each having its own maximum production rate determined in the concession decrees. The main focus of well performance analysis, using graphical analysis of the Jacob approximate equation, was to estimate the adequacy of the wells production rate as well as to identify possible changes in the technical status of the wells over years. 5 of total 30 wells were not included in the analysis due to technical issues during test performance. Well performance analysis includes the calculation of nonlinear well losses related to turbulent flow and linear head loss (aquifer and well) assumed to be related to laminar flow. Results indicate that the ratios between nonlinear well losses and linear head (well and aquifer) losses, in this paper referred as laminar losses, are from 6.9 % to 97.4 %. Laminar losses parameter suggests, all investigated wells were classified with either good (11 wells), medium (7 wells) or poor (7 wells) performance. The addressed analysis represents a very important basis for further thermal and mineral water extraction, e.g. optimizing the maximum allowed production rate as granted in concession decrees and diagnose potential changes in the technical status of each well

Analysing the Material Suitability and Concentration Ratio of a Solar-Powered Parabolic trough Collector (PTC) Using Computational Fluid Dynamics

Solar-powered desalination is a sustainable solution for countries experiencing water scarcity. Several studies have presented different solutions to provide cleaner production in desalination systems. Parabolic trough collector (PTC) is one of these solutions that has proven to be superior among solar concentrators. Furthermore, a number of studies have investigated the use of PTC for distillation of saline water in response to water scarcity. In this study, a modified PTC model was developed, in which the heat exchanger was replaced by a condensation tube to reduce the energy consumption, and a black layer was introduced to the surface of the receiver to enhance its absorptance. As a reference case, the system productivity according to average solar intensities in Zagazig, located at 30°34′N 31°30′E in the North East of Egypt, is estimated. The results indicated that the maximum production rate that can be attained is 1.72 kg/h. Then, the structure of the system is evaluated with the aid of Computational Fluid Dynamics (CFD) modelling, in order to enhance its productivity. Many materials are examined and the results recognised copper as the most suitable material amongst marine grade metals (i.e., aluminium, galvanised steel and stainless steel) to construct the receiver tube. This is due to its superior thermal performance, satisfactory corrosion resistance, and acceptable cost. Afterwards, the selected receiver tube was employed to identify the optimal Concentration Ratio (CR). Consequently, a CR of 90.56 was determined to be the optimum value for Zagazig and regions with similar solar radiation. As a result, the system’s productivity was enhanced drastically, as it was estimated that a maximum production rate of 6.93 kg/h can be achieved.

Vapor-Phase Photocatalytic Overall Water Splitting Using Hybrid Methylammonium Copper and Lead Perovskites

Films or powders of hybrid methylammonium copper halide perovskite exhibit photocatalytic activity for overall water splitting in the vapor phase in the absence of any sacrificial agent, resulting in the generation of H2 and O2, reaching a maximum production rate of 6 μmol H2 × g cat−1h−1 efficiency. The photocatalytic activity depends on the composition, degreasing all inorganic Cs2CuCl2Br2 perovskite and other Cl/Br proportions in the methylammonium hybrids. XRD indicates that MA2CuCl2Br2 is stable under irradiation conditions in agreement with the linear H2 production with the irradiation time. Similar to copper analogue, hybrid methylammonium lead halide perovskites also promote the overall photocatalytic water splitting, but with four times less efficiency than the Cu analogues. The present results show that, although moisture is strongly detrimental to the photovoltaic applications of hybrid perovskites, it is still possible to use these materials as photocatalysts for processes requiring moisture due to the lack of relevance in the photocatalytic processes of interparticle charge migration.

A comparative study of PSO, GSA and SCA in parameters optimization of surface grinding process

The selection of parameters in grinding process remains as a crucial role to guarantee that the machined product quality is at the minimum production cost and maximum production rate. Therefore, it is required to utilize more advance and effective optimization methods to obtain the optimum parameters and resulting an improvement on the grinding performance. In this paper, three optimization algorithms which are particle swarm optimization (PSO), gravitational search, and Sine Cosine algorithms are employed to optimize the grinding process parameters that may either reduce the cost, increase the productivity or obtain the finest surface finish and resulting a higher grinding process performance. The efficiency of the three algorithms are evaluated and comparedwith previous results obtained by other optimization methods on similar studies.The experimental results showed that PSO algorithm achieves better optimization performance in the aspect of convergence rate and accuracy of best solution.Whereas in the comparison of results of previous researchers, the obtained result of PSO proves that it is efficient in solving the complicated mathematical model of surface grinding process with different conditions.