Janaka R. Gamage

String hoppers are a staple food in Sri Lanka, characterized by consistently high demand in restaurants and canteens. However, supply often falls short due to the laborintensive and time-consuming nature of traditional preparation methods. The current market primarily offers separate machines for mixing and extrusion processes, which can lead to hygiene issues and inconsistencies in product quality. This paper presents an integrated string hopper maker that automates the process of dough mixing and extrusion for SME. The objectives include identifying critical parameters like water-flour ratio and water temperature, designing an integrated system to eliminate the manual dough handling, and developing a working prototype. The resulting machine is expected to enhance and ensure consistent quality and hygiene, and help food centers to meet market demand effectively, thereby increasing their sales and competitiveness in the market.

Cinnamon holds global recognition as a necessary spice and a vital food ingredient. Apart from being highly regarded as a spice, it shines in areas such as medicine, as a powerful agent against cancers, heart diseases, and diabetes [1], [2]. Various cinnamon breeds exist worldwide. True Cinnamon, native to Sri Lanka and commonly known as Ceylon Cinnamon, is renowned for its superior taste, aroma, and quality. It contains significantly less coumarin, a potentially harmful substance when compared to alternatives such as Cassia cinnamon [3], [4]. Cinnamon trees yield various extractants, including cinnamon oil from leaves. The most sought-after extract is obtained from the inner bark, which is the primary focus of this project. The cinnamon industry exhibits remarkable resilience and growth, continuing strong export performance during the pandemic. While it faces fierce competition from Chinese Cassia in terms of quantity, Ceylon cinnamon remains unrivalled in quality. Cinnamon extraction is a labour-intensive process cantered around harvesting the prized inner bark of cinnamon stems. Skilled workers are pivotal for ensuring product quality and process efficiency. High labor costs and the need for specialized skills in cinnamon processing pose significant challenges, leading to demotivation among planters and exacerbating the labor shortage issue. In addressing above gaps, this research aims to design and develop an automated machine for cinnamon processing that includes the functions: scraping, rubbing, and peeling in a single feed, as a solution for the high demand of skilled laborers, with high efficiency and acceptable quality output.

Plastic materials have been widely used to replace metals in functional parts due to their lower cost and comparable technical properties. However, the increasing use of virgin plastic material in consumer and industrial applications has placed a significant burden on waste management due to the volume of waste created and the potential negative effects of its end-of-life processing. There is a need to adopt circular economy strategies such as plastic recycling within industrial applications in order to reduce this significant waste management pressure. The present study used recycled polylactic acid (PLA) material as a feedstock for the 3D printing of a centrifugal semi-open pump impeller. The technical performance of 3D printed recycled PLA material and virgin PLA material was compared in this study. The environmental impacts for technically feasible impellers were assessed through the environmental life cycle assessment, while costs were evaluated by life cycle costing. The results were incorporated into a techno-eco-efficiency framework to compare the technical properties, environmental impacts, and costs. The social impacts of additive manufacturing and recycled feedstock material were also explored. The technical assessment results indicated that tensile strength, fatigue strength, density, and hardness decreased with recycled material content compared to virgin material. Microscopy of the fracture surfaces revealed the presence of slightly higher porosity and defects in recycled specimens, which could result in slightly lower technical properties. However, the recycled material was accepted for further ecological analysis as it offered higher pumping performance when compared to the original component and could reduce the burden on virgin material-based production and waste material disposal. Importantly, the results showed that 3D printed recycled PLA impellers are more eco-efficient when compared to 3D printed virgin PLA impellers.

The economic, environmental, and social impacts caused by the extensive resource consumption and harmful emissions from the metal manufacturing industry should be lowered through innovative sustainable manufacturing strategies. This study aims to investigate the techno-eco-efficiency performance of metal 3D-printed parts in comparison with CNC-machined parts to determine the technical, economic, and environmental performance as a decision support tool for selecting the most techno-eco-efficient manufacturing method. In this study, a novel metal extrusion 3D printing technology has been used to create a centrifugal semi-open pump impeller in 316L stainless steel material. The technical feasibility of the impellers has been determined by evaluating the geometry, build material, mechanics, morphology, and functional performance of the impellers. The eco-efficiency performance of technically feasible impellers was evaluated through environmental life cycle assessment, life cycle costing, and portfolio analysis. This eco-efficiency analysis helped ascertain the cost-competitiveness and environmentally friendliness of the 3D-printed impellers by comparing it with the conventional impellers. The findings reveal that the AM impeller is eco-efficient mainly due to lower normalised environmental impacts (54.6%) compared to the SM impeller. The functional parts made by metal extrusion 3D printing are technically feasible, cost-effective, and environmentally friendly compared to the SM counterparts.

The manufacturing sector accounts for 40% and 25% of global energy and resources consumption respectively. Machining is one of the most power-intense operations in the manufacturing sector making a significant contribution to the environmental footprint. The purpose of this study is to identify the key parameters that contribute towards the environmental impacts of conventional turning. A set of experiments was designed using the Taguchi L₉ method. Experiments were performed to analyse the electrical energy consumption, metalworking fluid (MWF) consumption, surface roughness, and material removal rate during turning of AISI P20 with both wet and dry machining. A life cycle assessment (LCA) was conducted to assess the environmental performance of turning. A multi-response optimisation was performed to identify the optimum operating conditions. The results show that turning with wet machining yields better machining and environmental performance compared to dry machining. The LCA results reveal that electrical energy is the highest contributor under most of the impact categories, while the effect of MWF is negligible. The use of workpiece material and cutting insert material contribute significantly to the impacts under aquatic ecosystem and resource depletion damage categories. Further, optimum parameters were proposed considering both machining performance and environmental impact.

Original Equipment Manufacturers (OEM) are shifting towards remanufacturing, signalling growth in new investments in remanufacturing. It is a noticeable global trend owing to the popularity of circularity and sustainability concepts, catalysed by environmental legislations and profit motives. Thus, the development of effective business models for remanufacturing is essential. However, capturing the entirety of business components essential for remanufacturing is yet to be seen in the industry. The purpose of this research is to develop a comprehensive business model for automotive parts remanufacturing considering all major business components, namely: customer segments; value propositions; channels; customer relationships; revenue streams; key resources; key activities; key partnerships; and cost structure. In this pursuit, a thematic analysis of related literature was conducted to define the identified business components. The Business Model Canvas framework was used to present the developed business model in the context of automotive parts remanufacturing. The resultant business model with nine components is expected to support decision-making for investors and entrepreneurs in the automotive remanufacturing industry.

The interest in using scaled models for dynamics testing of prototype vehicles is growing due to the high demand for autonomous driving. In the early design phases, vehicle testing is done using computer simulations. Even though computer simulations are proven to be extremely helpful in designing prototypes, simulation models need to be validated using realworld testing. There are high costs involved in vehicle testing and it’s dangerous to conduct aggressive driving manoeuvres with real drivers. As a solution, researchers have used scaled models. To validate the computer simulations, researchers matched the scaled model test data with full-size vehicle prototypes considering the dynamic similitude. However, previous work was limited to the analysis of the steady-state behaviour of vehicles. To accurately predict the behaviour, the transientstate response must be tested as well. Therefore, this paper outlines the precursory work of a scaled model with the ability to test both states during vehicle manoeuvres. This paper is structured as follows. Section II presents related work. Section III elaborates on the mathematical modelling and present the results of the computer simulations. Section IV presents the scaled model which will be developed. Section V concludes the findings, and present the future work of research.

Polyethylene Terephthalate (PET) has become the most commonly used material in the global beverage bottling industry. PET bottle production has increased by over seven times within the last three decades. However, the use of PET has a considerably detrimental effect on the environment, and many studies have been carried out on curbing this damage. Reducing the amount of material used, design for recycling, repurposing, and reusing are possible approaches for mitigating the negative environmental impacts of the PET bottle industry. The local PET bottle market has a range of products to cater the various customer requirements. To obtain a holistic vision of the actual impacts of this industry, life cycle thinking becomes necessary. The objective of this study is to present a methodological framework for comparing the environmental performance and structural performance of PET bottle designs, using case studies from the Sri Lankan market. A life cycle assessment and a finite element analysis were carried out to evaluate the overall environmental impacts of the PET supply chain and the structural performance of PET bottles. The outcomes of the study are used to provide recommendations on the short and long-term strategies to increase the eco-friendliness of the PET bottle industry.