Engineering Headway Vol. 21

Abstract: Displacement can occur for a variety of reasons, including pedicle screw detachment from the spine, damaged pedicle screws, the supporting rod detaching from the pedicle screw, and broken supporting rods. The relationship between displacement and screw threads indicates that the displacement of the screw is a measure of thread movement, and the smaller the pitch (the space between the two screw threads), the lower the displacement of the screw. Results from a normal bone simulation using MSC-Marc show that variations in pedicle screws under tensile load result in a displacement of 5.53x10-5 mm for single-threaded conical pedicle implants, with no greater coefficient of friction than single-threaded cylindrical implants, which have a displacement of 1.62x10-6 mm. When a tensile load is applied to an osteopenia bone, a single-threaded conical implant with no coefficient of friction results in a displacement of 3.45x10-5 mm as opposed to a cylindrical implant. The higher contact force reinforces the pedicle screw's interface with the bone, making it less likely to detach due to the pedicle screw's tensile force. When applying tensile forces and bending moments to a single-threaded conical implant with a single-threaded cylindrical implant, the displacement increases as the friction coefficient rises

Abstract: To meet the needs of road marking design and manufacturing, we ensure that our products meet the ergonomic aspects. strong, comfortable and esthetical. Strength, of course, has something to do with the strength of the material and the structure stability of the road marking products. Plastic road marking material are not strong enough to withstand large impacts. Concrete road markers are also heavy and difficult to transport and install because they require a mobile crane. Based on this, temporary road markings are made from concrete foam composites, the mass of which is lighter than concrete and stronger than plastic. The purpose of this study was to analyze the responses of road markers under impact loading produced by motor cycle. Ansys software is used as a numerical tool to simulate the stability of the structure of road markings. There are two-types of road marking models. Type 1 is a two-part in which both pole and base structure can be separately manufactured and assembled. Type 2 consists of one parts pole integrated with base structure of markers. The shape of the road markings is a hollow pole of 750 mm long with inner diameter of 50mm and outer diameter of 100mm. The base structure has 100mm thick and outer diameter of 300mm. To evaluate the responses of markers, a FEM based ANSYS software is used. Providing a motor cycle impact load of 100kg at 188 mm from base with a speed of 40km/h, the structural integrity of markers, that is, their response to static external loads is calculated. It is shown that the equivalent stress and stress in y-direction reach the maximum values when impacted on B location both for type 1 and type 2, respectively. For both cases the stress values are far below the ultimate tensile strength of the concrete foam materials. Thus, the impact load will not cause the failure of the road markers structure. In terms of production, type 2 road markers are easier to manufacture. It can be casted in two parts: base structure and pole. They are also practically easy for loading and unloading. Thus, for the continuation of research the type 2 road markers will be produced and tested in our research center. Keyword: Road Markers, Concrete Foam Composite, Motor Cycle Load. Software Ansys

Abstract: Presently available motorcycle helmet designs in the market adhere primarily to the Indonesian National Standard (SNI) 2007, which dictates sizing based solely on inner circumference and height while disregarding anthropometric data. Based on the research findings, consumer preferences for helmet products indicate a prioritization sequence of technical characteristics, with the highest ranking as follows: “Helmet safety during usage” has a relationship value of 63% with a contribution value of 2.601; “Size” that accommodates the user has a relationship value of 62% with a contribution value of 2.583; “Maintenance of airflow within the helmet” has a relationship value of 57% with a contribution value of 2.283; “Comfortable helmet use” has a relationship value of 52% with a contribution value of 2.087; “Competitive pricing” has a relationship value of 38% with a contribution value of 1.246; “Ergonomic features” of the helmet has a relationship value of 33% with a contribution value of 1.425; “Durability and longevity” have a relationship value of 31% with a contribution value of 1.216; and “Helmet aesthetics” has a relationship value of 30% with a contribution value of 1.216. For size S: Helmet width 17.67 cm, Helmet circumference is 58.29 cm, Helmet height is 26.56 cm, Distance from Ear to Top of Helmet is 16.95 cm, Helmet Length is 20.33 cm, Helmet Visor Height is 9.95 cm, Ear Position Length on Helmet is 4.14 cm, Ear Position Width on Helmet is 1.94 cm, and The distance from the mastoid to the helix at the height of the tragus (Pinna height) on Helmet is 1.98 cm. For size M: Helmet width is 19.65 cm, Helmet circumference is 63.11 cm, Helmet height is 28.14 cm, Distance from Ear to Top of Helmet is 18.17 cm, Helmet Length is 22.13 cm, Helmet Visor Height is 12.35 cm, Ear Position Length on Helmet is 4.13 cm, Ear Position Width on Helmet is 2.97 cm, Pinna height on Helmet is 2.86 cm. For size L: Helmet width is 21.14 cm, Helmet circumference is 67.41 cm, Helmet height is 29.92 cm, Distance from Ear to Top of Helmet is 20.48 cm, Helmet Length is 23.80 cm, Helmet Visor Height is 14.43 cm, Ear Position Length on Helmet is 4.12 cm, Ear Position Width on Helmet is 4.00 cm, and pinna height on Helmet is 3.76 cm. For size XL: Helmet width is 21.38 cm, Helmet circumference is 68.44 cm, Helmet height is 31.45 cm, Distance from Ear to Top of Helmet is 22.76 cm, Helmet Length is 25.48 cm, Helmet Visor Height is 15.78 cm, Ear Position Length on Helmet is 4.03 cm, Ear Position Width on Helmet is 4.91 cm, and Pinna height on Helmet is 4.97 cm.

Abstract: Modeling and simulation are one of the ways to represent and solve the problem that occurs in real-world situations. One of the renowned methods of simulation modeling is Agent-Based Modelling Simulation (ABMS). ABMS is driven by the need for deep insight for analyzing system behavior and evaluating strategies to give a picture of a system's description and prediction. This study reviewed the state of the art related to ABMS and correlated the study with the application in manufacturing. This paper aims to elaborate a framework for constructing and developing ABMS as well as discussing the application of ABMS in the manufacturing sector. This paper classified five fields in manufacturing that very essential now and in the future, which possibly can be enhanced and optimized by using ABMS.

Abstract: Micro, small, and medium enterprises (MSMEs) play a crucial role in driving economic growth and absorbing labor. MSMEs' contribution to the Indonesian economy includes their ability to absorb 97% of the total workforce available. Tofu is one of Indonesia's micro, small, and medium enterprises. According to previous research results on posture assessment in the filtering workstation, the assessment workstation's working posture received a score of 13, indicating a very high risk of musculoskeletal disorders (MSDs) and necessitating immediate corrective action. This research aims to analyze workers' working times and motions. The research results show that the standard time for workers filtering tofu pulp using a swing is 31.21 minutes, while the standard time for workers filtering tofu pulp using a pressing cloth is 14.4 minutes. Based on the analysis of work motions using the Modular Arrangement of Predetermined Time Standards (MODAPTS) approach, 14 motions do not align with the principles of motion economy. We can take several measures to ensure alignment of motions with the principles of motion economy and reduce the risk of MSDs, such as eliminating rotational and walking movements, simplifying movements by relocating work facilities to the left and right of the workers, and designing a filtering machine.

Abstract: This study evaluates the effect of varying roasting times and storage durations on the moisture content and hardness of Coffea arabica and Coffea canephora beans. Heat treatment was applied at a temperature of 250°C for 5, 10, 15, and 20 minutes, followed by moisture testing using a Moisture Analyzer and hardness testing with a Shore A durometer. The results showed a significant decrease in moisture content as roasting time increased, with the largest reduction observed after 20 minutes of roasting. After one week of storage in airtight containers, all samples exhibited an increase in moisture content, although beans with longer roasting times maintained lower moisture levels compared to unroasted beans. Hardness measurements did not reveal a consistent pattern related to roasting time, but all samples registered values above 80 Shore A. This study provides insights into the impact of heat treatment and storage on the physical characteristics of coffee beans, which is relevant for optimizing the quality of the final product.