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Filament-based material extrusion additive manufacturing (FMEAM) is an additive manufacturing technique that uses 3D printing. Additive manufacturing could build parts with infill variations. Solid or triangular infill pattern could be selected as needed. The solid pattern will have the maximum material volume, while the triangular pattern will contain a triangular lattice structure that fills the voids in the volume so the material requirement is reduced. This is valuable in optimizing the requirements of metallic materials for mechanical properties without changing the surface shape. The alloy Inconel 625, which is very popular in the aerospace industry have been developed as a feed material of FMEAM. However, for developing rotating parts, such as turbine blades, impact toughness, surface roughness and microstructure need to be investigated. This research was conducted to determine the effect of the infill pattern on the impact toughness, morphology of surface fracture, microstructure of side surface and surface roughness with Inconel 625 material built using FMEAM. The Charpy impact test, s ASTM 23, with v-notch testing method and SEM with EDS were performed. The results showed that the impact toughness for solids was higher than the value for the triangular infill pattern. It was discovered that the cavities in the triangular lattice structure within the specimen reduced the impact toughness to 57.6%. Micropores and residual polymer trapped on the surface reduce impact toughness. However, the same surface shape on solid and triangular infill patterns with surface roughness of 2.44 and 10.03 µm is still feasible for manufacture. [ABSTRACT FROM AUTHOR]

CNC milling machine is a production machine which widely used to manufacture many kinds of products. In the process of milling machining, the time needed to produce a component must be as minimum as possible to minimize the costs and its impacts on the environment. One of energy consumptions used in CNC milling machines is to supply electric motors for each axis of motions. Cutting energy consumption can be minimized by optimizing the cutting parameters, such as the cutting toolpath. Modelling and comparing the total energy consumption of the cutting process from different cutting toolpaths and strategies are important in selecting the right toolpath that has the smallest energy consumption. To achieve this goal, this study models the energy consumption during the cutting process. The model is then used to evaluate and compare different cutting toolpaths from different cutting strategies. Three prismatic and one sculptured part were used to examine the model of cutting energy consumption. A Graphical User Interface is also developed to simplify the comparison and evaluation process. Through this process it will be possible to predict energy consumption in the cutting toolpath and hence enable the selection of the right toolpath to reduce energy consumption in machining.

In this paper, a mechanism of visual servoing for mobile microrobot with a centralized camera is developed. Especially for the development of swarm AI applications. In the fields of microrobots the size of robots is minimal and the amount of movement is also small. By replacing various sensors that is needed with a single centralized vision sensor we can eliminate a lot of components and the need for calibration on every robot. A study and design for a visual servoing mobile microrobot has been developed. This system can use multi object tracking and hough transform to identify the positions of the robots. And can control multiple robots at once with an accuracy of 5-6 pixel from the desired target.

Micro milling is currently being used to make micro-sized products, such as in MEMS, medical devices, etc. But in the process of machining, especially in roughing process, micro milling spends a lot of energy that can still be reduced to contribute to green manufacturing. This study focuses on developing the model of energy consumption during the micro milling processes. The model is then used to map the energy consumption from different cutting toolpaths and strategies. Furthermore this study also comparing and characterizing the energy consumed between macro milling and micro milling of the same part shape but with significant different in size. In conclusion, this study shows different characteristics and comparison in energy consumption between micro milling and macro milling.

Landscape and infrastructure are two main basic aspects which play a significant role for any universities in achieving environmental, social-behavioural, or aesthetic outcomes. This paper describes the setting and infrastructure management at the Universitas Indonesia (UI) as a continuous effort towards green and sustainable campus. Some developments and improvements have been made during the last three years, such as forest city maintenance, development of pedestrian boulevard, and installation of road marks and traffics signs. In addition, infrastructures have been improved by replacing conventional lamps with LED type ones, development of real-time energy consumption monitoring system, green chilling system, solar photo-voltaic development, solar cooling absorption chiller system, air conditioning with VRF/VRV system, and preparation for green certified building. These improvements on campus setting and landscape are reflected on the UI GreenMetric 2017 results which ranked at #23 worldwide with the score of 957 out of 1500 total score for “setting and infrastructure” category. With regards to these achievements, some challenges and strong commitment in sustainability policy need to be implemented in the forthcoming years to maintain the UI’s vision to be a “world class sustainable university”.

Bending in sheet metal forming is defined as uniformly straining process around a linear axis. A V-bending process is normally used in sheet metal working due to the tool and process simplicity. The main problem in bending process is a springback occurrence which causes an error in part dimension. In a micro level, the springback angle is difficult to be assessed because of the influence of size effects in all aspects of the system. The springback behavior has been investigated in many previous kinds of research. However, the springback correction is still needed to be studied extensively so that it can be implemented reliably in micro-bending. The purpose of this research is to investigate the influence of punch velocity and holding time to the springback angle. The process is performed to the 0.1 mm thickness of copper foil. The punch velocities are 0.1 mm/s, 1 mm/s, and 10 mm/s. While the variation of holding time, which is set during the bottoming stage, are 7 s, 9 s, and 11 s. The result shows that the punch velocity clearly influences the springback angle. In addition, the holding time during the bottoming stage is a potential factor in springback angle correction.

One of the factors affecting the effectiveness of machining time of 5-axis miling is the method being used. By using flank milling method, as one of the optimized processes to make a workpiece, the time required for the process becomes shorter.This research is aimed at developing the method for determining the initial orientation of the tool for a sculptured surface on the basis of faceted model. By determining cc-point as the basis for positioning the tool on the surface of the workpiece, the cutting direction is formed from the nearest cc-point in the XY flat plane direction of the faceted model at the spatial coordinate. The positioning of the tool is initially based on the Local Coordinate System developed by the cross product between the normal vector nat each cc-point and cutting direction vector Ffrom one cc-point to the other. The cross product resulted is a tangent vector Tof the plane formed from the normal vector and cutting direction. The orientation of the tool is formed and defined by an inclination angle (α) and a screw angle (β). Maximizing the cutting volume and avoiding gouging at each cc-point during the flank milling are carried out through optimal adjustment of these two rotational angles. Furthermore, when the adjustment of rotational angles cannot resolve the gouging, appropriate tool lifting along the normal vector is conductedhis method is very much applicable for flank milling having the basis of data in the form of faceted models.

The increase in the volume of rough machining on the CBV area is one of the indicators of increased efficiencyof machining process. Normally, this area is not subject to the rough machining process, so that the volume of the rest of the material is still big. With the addition of CC point and tool orientation to CBV area on a complex surface, the finishing will be faster because the volume of the excess material on this process will be reduced. This paper presents a method for volume calculation of the parts which do not allow further occurrence of the machining process, particulary for rough machining on a complex object. By comparing the total volume of raw materials and machining area volume, the volume of residual material,on which machining process cannot be done,can be determined. The volume of the total machining area has been taken into account for machiningof the CBV and non CBV areas. By using delaunay triangulation for the triangle which includes the machining and CBV areas. The volume will be calculated using Divergence(Gaussian) theorem by focusing on the direction of the normal vector on each triangle. This method can be used as an alternative to selecting tothe rough machining methods which select minimum value of nonmachinable volume so that effectiveness can be achieved in the machining process.