The Implementation and Analysis of a Tendon-Based-Stewart-Gough-Platform (SGP) for an Automated Storage and Retrieval System for Mini-Load

Eine Umsetzung und Analyse einer Seilgetriebenen Stewart-Plattform als Teil eines Automatisierten Regalbediengerätes für Automatische Kleinteilelager Ziel dieser Arbeit ist die Untersuchung aller Aspekte und Rahmenbedingungen bei der Ent-wicklung des SGP-Regalbediengeräts, sodass dieses am Ende problemlos in die innerbe-trieblichen Materialflusssysteme integriert werden kann. Von dem SGP-Regalbediengerät werden hohe Anforderungen wie hohe Durchsatzleistung und hohe Dynamik, Reduzierung der zu bewegenden Massen, hohe Energieeffizienz, Umweltschutz, hohe Wirtschaftlichkeit, Preisreduzierung im Unterschied zum anderen Konkurrenten etc. erwartet. Eine weitere Her-ausforderung ist, dass das SGP-Regalbediengerät auf einer neuartigen Technik beruht, die noch nie im Logistikbereich eingesetzt wurde, sondern bis jetzt nur im Robotikbereich ange-wendet wurde. Im Rahmen dieser Arbeit werden ausschließlich automatische Kleinteilelager (AKL) betrach-tet. Das AKL ist ein häufig in der Lager- und Kommissioniertechnik eingesetztes System. Das Regalbediengerät ist ein zentrales Element des AKLs. Die aktuellen Forschungsarbeiten auf dem Gebiet der Regalbediengeräte konzentrieren sich im Wesentlichen auf die Verbesserung der bestehenden Komponenten. Untersucht wird der Einsatz neuer Werkstoffe für Teilbereiche der Regalbediengeräte und die Nutzung von ener-gieeffizienten Betriebsverfahren. Die dabei zu erreichenden Leistungen sind an die Grenzen der Technik gestoßen. Das SGP-Regalbediengerät beruht dagegen auf einer neuartigen Technik, die bis jetzt nicht im Logistikbereich eingesetzt wurde. Dabei wird das klassische Regalbediengerät durch eine Plattform, die an acht vorgespannten Seilen befestigt ist, ersetzt. Die Plattform wird mithilfe von acht Motoren, die unter Einsatz modernster Regelungsverfahren computergesteuert werden, bewegt. Dieser einfache Aufbau führt dazu, dass besonders niedrige Massen bewegt werden müssen. Außerdem werden Kunstfaserseile, die ein Vielfaches leichter als die konventionellen Stahlseile sind, verwendet. Dies führt dazu, dass die bereitgestellte Antriebs-leistung weitgehend für die Bewegung der Nutzlast genutzt wird. Mithilfe des Stewart-Gough-Plattform Regalbediengeräts werden höhere Geschwindigkeiten, Beschleunigungen und infolgedessen höhere Umschlagsleistungen erreicht. Außerdem spielt die Energieeffizienz und die zu bewegenden Masse eine große Rolle bei ihrer Entwicklung. Im Rahmen dieser Arbeit wird eine Marktanalyse durchgeführt. Sowohl die Bedürfnisse eines Marktes als auch die Kompetenzen des Unternehmens sind jedoch dynamisch. Durch diese Marktanalyse werden die Kundenbedürfnisse, Kundennutzen und Ein-kaufsvolumina ermittelt. Im Rahmen der Marktanalyse werden sowohl sechs konventio-nelle, als auch andere Arten von Regalbediengeräten vorgestellt und mit dem SGP-RBG verglichen. Die Anzahl der gelieferten Regalbediengeräte wird in Deutschland und international analysiert. Schließlich werden die Umschlagsleistungen des SGP-RBGs berechnet und mit sechs anderen Konkurrenten verglichen. Dabei werden sowohl Einzelspiel- als auch Doppelspielzeiten für verschiedene Lagerabmessungen berechnet. Danach wird die Entwicklung des Systemsaufbaus im Laufe der Zeit näher erläutert. Hierbei werden auch die Systemkomponenten näher beschrieben.The warehouse plays an important connecting role in the logistics network inside the company and between the various processes within the company. Its major role is to maintain a constant supply of the products, maintenance of products for a specific time period and control the supply requirement, the consumer requirement and the demand of the situation. Hence, a methodology to improve the efficiency of a new design of the Automated Storage/Retrieval System to increase the throughput performance of the system is strictly required. Until now, all efforts to design Automated Storage and Retrieval Systems AS/RS have been carried out with Storage/Retrieval (S/R) machines. These have disadvantages of high investment value and restricted use due to the inflexibility of the physical layout. However, little attention has been paid so far to making use of the principles of the Stewart-Gough-Platform SGP on AS/RS. To construct new designs, we set up a system under the name SGP-AS/RS. This system has attractive features such as high performance and scalability. An SGP is a kind of cable-driven platform with parallel manipulators using an octahedral assembly of struts which has six degrees of freedom (x,y and z). Additionally, another analysis, which can help to obtain a methodology for estimating the single command and dual command cycle time of the SGP-AS/RS, is based on some assumptions. The resultant methodology depends on some parameter values, like dimensions of storage racks, location of the (I/O) points, maximum velocity consideration and acceleration/deceleration rate changes. These could also be used in future for selecting the right kind of (S/R) machine for this system. This tool was integrated with the main design tool, hence one could automatically evaluate the mid and maximum, single and dual command cycle time for the newly designed SGP-AS/RS. An integrated storage system containing 5000 rack Bays has been presented, as well as the performance calculations of SGP-AS/RS with comparable storage and retrieval systems. At the same time, specified constraints were carried out. These calculations are based on the projected performance of the SGP-AS/RS. In contrast, the performance of comparable storage and retrieval systems are specified by the manufacturer. Finally, the results of the designed SGP-AS/RS system are presented at the end of the dissertation, highlighting the important design parameters and the expected throughput from the system

An Automatic Yogurt Filling System Built from Scratch Based on Industry 4.0 Concept

The movement to digitally transform Saudi Arabia in all sectors has already begun under the focused “Vision 2030” programme. Consequently, the task of renovating and standardizing manufacturing and other production industries to compete with global challenges is essential. The fourth industrial revolution (Industry 4.0), triggered by the development of information and communications technologies (ICTs), provides a basis for smart automation using decentralized control and advanced connectivity (e.g., Internet of Things). In the areas where the spirit of Industry 4.0 has been embraced, some industries have already implemented these ideas and yielded gains. Learning the principles of Industry 4.0 and having knowledge of this digital industrial revolution is essential for future engineering graduates. In this paper, a case study on building a learning factory from scratch based on the concept of Industry 4.0 is introduced. The initial achievement of a fully automated production line is presented. In doing so, a system with a smart design having smart control and smart monitoring is developed

Initial Assessment on Feasibility of Remanufacturing Practice: Case of Air Conditioners

Abstract- Due to the environmental regulations and economic viability, many industries show growing interest in the product recovery. Product recovery strategies (sometimes called end-of-life (EoL)) are recycling, remanufacturing, reuse, and refurbishment of components. Remanufacturing is a process that brings end-of-life product to its “like-new†conditions, the process recover product functions and quality, the remanufactured product is as its equivalent new with same warranty and less purchasing price. The price difference is associated with saving in energy, material and other resources recovered from the EoL product.  The air-conditioning is the most energy consuming sector in Saudi Arabia (the geographical location of the study) where it consume 60-70% of the total residential energy. This study provide initial investigation and assessment  of  Business models for remanufacturing of window air-conditioner., a survey regarding the customer behavior has been conducted, it assesses  how users deal with EoL Air-Conditioner, it also measures their perceptions about the remanufacturing process. Moreover, the paper describes the importance of remanufacturing in the context of reverse logistics. Results show that the cost structure is the driving force of conducting the remanufacturing of the air-conditioner.   Keywords: Remanufacturing; business model of remanufacturing; air conditioner

3D Simulation of a Yogurt Filling Machine Using Grafcet Studio and Factory IO: Realization of Industry 4.0

Manufacturing systems, enterprises and academic institutions worldwide are implementing Industry 4.0 (IR4.0). By integrating the services and equipment, IR4.0 develops autonomous systems that manage industrial operations and exchange real-time data in real time. This study includes a simulation of an existing production system using the GRAFCET Studio software. To realize the concept of a 3D smart factory, the GRAFCET programming language was used and connected to the Factory IO software. The simulation can accurately replicate the filling, scanning and removing processes in an actual yogurt filling system. A virtual factory was designed and developed using the IO Factory software to clarify the workflow and simplify the modification of the production line. This virtual factory better enables the identification of areas for optimization, improving also efficiency and productivity. A comparison between the simulated and the actual system results shows that the simulated results are approximately 90% accurate. In addition, some improvements are proposed to enhance the existing system\u27s efficiency. The improvements involved the testing of the system under different conditions to identify shortcomings and modify the design accordingly

Exploring the mechanical, tribological, and morphological characteristics of areca fiber epoxy composites reinforced with various fillers for multifaceted applications

This investigation is primarily concerned with the effect of fly ash, basalt powder, and tungsten carbide (WC) on the mechanical, microstructural, and tribological behaviour of areca fiber-reinforced composites. The fillers (5–10 wt. %) were included with the areca fiber epoxy reinforced composites. In comparison to areca fiber composites without fillers, the inclusion of fly ash, basalt powder, and WC increased the tensile strength by 33–48.2 MPa. The tensile strength of an A2 composite containing areca fiber (20 wt. %), epoxy (70 wt. %) and basalt powder (10 wt. %) was measured to be 48.2 MPa. Similarly, filler incorporation enhanced flexural, impact, and Shore D hardness properties by up to 21.25%, 13.18%, and 15.66%, respectively. Furthermore, the hybridization of fillers enhanced the mechanical properties and abrasion resistance of areca fiber reinforced composites. The inclusion of filler increases the load-carrying capability and adhesion, as determined by SEM. The river-like pattern demonstrates that ductile failure was dominated in the A5 [areca fiber (20 wt. %), epoxy (70 wt. %), fly ash (5 wt. %) and basalt powder (5 wt. %)] composites. A4 [areca fiber (20 wt. %), epoxy (70 wt. %), fly ash (5 wt. %) and tungsten carbide (5 wt. %)] composite has a lower wear resistance than all other composites. The hybrid filler-reinforced composite exhibits increased wear resistance as a result of the absence of wear detritus and textured surfaces.publishedVersio

Implementation of environmentally sustainable practices and their association with ISO 14001 certification in the construction industry of the United Arab Emirates

Despite significant worldwide growth in ISO 14001 standard adoption by construction firms, limited research exists on issues related to the implementation of environmentally sustainable practices and their associations with ISO 14001 certification. This article reports the results of an empirical study examining the implementation of environmentally sustainable practices, the link between their usage frequencies and ISO 14001 standard adoption, and the association between having this standard and firm size. The methodological approach involved interviews followed by a structured questionnaire to collect data from 259 construction firms in the United Arab Emirates. The results indicate that (1) environmentally sustainable practices have not been used extensively and those that have been implemented have varying usage frequencies, (2) adoption of the standard has been accompanied by partial improvement in the usage frequencies of the practices, and (3) there is no association between firm size and adoption of the standard. These findings can serve as a guide for policymakers as well as project managers in construction firms that are interested in implementing environmentally sustainable practices and those that are planning to invest in ISO 14001 certification

Improved MRO inventory management system in oil and gas company : increased service level and reduced average inventory investment

This study proposes a methodology for the oil and gas businesses to keep their production plant productive with a minimum investment in carrying maintenance, repair, and operating inventory planning. The goal is to assist the exploration and production companies in minimizing the investment in keeping maintenance, repair, and operating (MRO) inventory for improving production plant uptime. The MRO inventory is the most expensive asset and it requires substantial investment. It helps in keeping the oil and gas production plant productive by performing planned and unplanned maintenance activities. A (Q, r) model with a stock-out and backorder cost approach is combined with a continuous inventory review policy for the analysis of class A items of oil and gas production plant MRO inventory. The class A items are identified through popular ABC analysis based on annual dollar volume. The demand for the inventory is modeled through Poisson distribution with consideration of constant lead time. The (Q, r) model in both stock-out cost and backorder cost approaches assigned higher order frequency and lower service level to low annual demand and highly expensive items. The stock-out cost approach shows an 8.88% increase in the average service level and a 56.9% decrease in the company average inventory investment. The backorder cost approach results in a 7.77% increase in average service level and a 57% decrease in average inventory investment in contrast to the company’s existing inventory management system. The results have a direct impact on increasing plant uptime and productivity and reducing company maintenance cost through properly managing maintenance stock. The analysis is carried out on the oil and gas production plant’s MRO inventory data, but it can be applied to other companies’ inventory data as well. All the results reflected in this research are based on the inventory ordering policy of two orders per year. The inventory ordering frequency per year may be other than two orders per year depending on the type of organization

Dysembryoplastic Neuroepithelial Tumour (DNET): A Rare Brain Pathology Presenting with Intractable Seizures

Dysembryoplastic neuroepithelial tumour (DNET) is a benign glioneuronal tumour often related with intractable localization – related seizures in both in paediatric age group as well as young adults. However, a small number appear to have the potential for malignant transformation. Total surgical removal without any adjuvant therapy is the gold standard treatment. We report a case in which DNET appeared in a 13 year old male. Cranial CT scan showed a discoid lesion with peripheral enhancement in right parietal lobe. Micro-decompression of the tumour was done. On histopathology, the tumour revealed features of WHO grade I dysembryoplastic neuroepithelial tumour

Midline Depressed Fractures of the Skull

Objective: To evaluate the results of management of middle depressed fracture skull.Depressed skull fracture is a common neuro-traumatic emergency. The commonest causes in our society are fall from height and road traffic accident. The frequency of depressed fractures is that it occurs in 75% in fronto-parietal region, 10%1 in temporal region, while in occipital is 5% and in others is 10%. In time surgical manage-ment gives excellent results and leads to minimize the sequel of this condition. Most of the causes can be pre-vented just by adopting preventive measures. The condition can be treated in periphery hospital as well, if trained personals are available. Midline depress fracture are rare. Depressed fracture over venous sinuses requires special handling. Surgical elevation involves massive blood loss. Most of them are treated conservatively.Material and Methods: We conducted a 4 years study in the department of Neurosurgery, Lahore General Hospital from 2009 to 2013.Results: We included 30 patients of mid line depressed fractures in which 20 were treated by surgical elevation and 10 by conservative management. Follow of 3 months to 1 year. In a total of 3750 patients who presented in the emergency department, 540 (14.4%) patients were operated for depressed skull fractures in which midline depressed fractures were 20 (4%). There were 20 patients in whom the anterior 1/3rd of superior sagittal sinus was involved, in 6 patients the middle 1/3rd of superior sagittal sinus was involved while in only 4 patients the posterior 1/3rd of superior sagittal sinus was involved. We paid special attention to these midline fractures involv-ing the venous sinuses. In 4 of our patient we encountered severe blood loss as the depressed fragment was being plugged in sinus tear. In 12 patients we carefully elevated the depressed fractures and gained control over the venous sinus as soon as possible with the help of spongiston and packing technique. In 8 patients the fracture site was not contaminated with foreign material, there was no cosmetic issue and no focal deficit found, they were managed by scalp debridement along thorough irrigation and primary closure. Out of operated 20 patients only two patients presented with mild wound infection but it settled down with proper antibiotic therapy. In the con-servative group out of 10 patients 2 patients developed epileptic seizure after 3 months and 7 months of trauma and they were managed by giving antiepileptic drugs.Conclusion: In our study we concluded that elevation of depressed fracture over SSS can be attempted whenever patients clinical condition warrant. Elevation of the bone along with debridement of the wound resulted in rapid and dramatic resolution of signs and symptoms of raised ICP and venous hypertension. The study also showed an improvement in the cosmesis and reduction in the overall wound infection rate