Applied Mechanics and Materials Vol. 842

Abstract: In recent years, robots have found extensive applications in automating repetitive, defined, position dependent tasks such as painting and material handling. However, continuous contact type tasks (such as finishing, deburring and grinding) that require both position and force control are still carried out manually by skilled labor. Majorly, because it is difficult to program experienced user skills in a robotic setup without having clear knowledge of underlying model used by the operators. In this paper we present a preparation for capturing human operator’s dynamics using an instrumented hand-held tool and a motion capture setup. We first present the design of an instrumented tool and later present a method for reliably capturing kinematics using redundant markers removing effects of marker occlusions, and effect of gravity caused by the tool's mass. Kinematic information is used for deriving the forces/torques on the tool end effector.

Abstract: The aim of this paper overviews about to find out the errors that come from three axis CNC vertical milling machine. The errors come from, the CNC milling machine can be modelled into mathematical models and later on these error models will be used to analyse the errors in the measured data. Many errors from CNC machine tools have given significant effects toward the accuracy and repeatability of manufacturing process. There are two error sources come from CNC machine tools such as tool deflection and thermal distortions of machine tool structure. These errors later on will contribute to result in the geometrical deviations of moving axis in CNC vertical milling machine. Geometrical deviations of moving axis such as linear positioning errors, roll, pitch and yaw can be designated as volumetric errors in three axis machine tool. Geometrical deviations of moving axises happen at every axis in three axis CNC vertical milling machine. Geometrical deviations of moving axises in linear and angular movement has the amount of errors up to twenty one errors. Moreover, this geometrical errors play the major role in the total amount of errors and for that particular reason extra attention towards the geometrical deviation errors will be needed along machining process. Each of geometrical error of three axes vertical machining center is modeled using a homogeneous transformation matrix (HTM). The developed mathematical model is used to calculate geometrical errors at each axis and to predict the resultant error vector at the interface of machine tool and workpiece for error compensation.

Abstract: The manufacturing process of lightweight and strong (Unmanned Aerial Vehicle) UAV and composite aircraft flight testing capability is described in this research. Nowadays, UAV development becomes more creative and high technology. Mapping and monitoring process from a UAV will be more effective and efficient. Mapping and monitoring process needs high durability UAV so that development with lightweight and strong material is needed. Lightweight technology is very suitable applied in the UAV technology. The composite material has many benefits for an aerodynamics world. The composite material was made of fiberglass and resin, and this material was used in components that are not loaded to high loads. The aircraft industry uses fiberglass composites widely because of the stiffness, strength, and toughness of composite.This research was conducted by manufacturing an aircraft with a fiberglass composite. The first manufacturing process was making a master prototype from styrofoam and then the styrofoam master was used to make a mold. The next process is called hand lay-up in which fiberglass and resin were laid to the model to produce half side of the aircraft. The process refined by vacuum bag to obtain a thin, flat, and good surface of the aircraft. Aircraft flight testing is needed to obtain statistical of the stability in pitch, roll and altitude, so the data result will determine the feasibility of composite aircraft in this research. The flight data have shown that the aircraft has high stability on roll and pitch.

Abstract: Programmable Logic Controller (PLC) is widely used to control systems on the manufacturing industry, automotive industry and etc. PLC is used to regulate the production process and machine systems to work simultaneously and continue. PLC has system to regulate the movement of machine components, displacement system of product, system settings motion or displacement of other components. PLC is a control system with some advantages such as simple in design, easy to use and circuit modification, low cost, easy maintenance, high reliability and safe. In this paper, we will focus on the PLC that used in the control of equipment movement on the rotary dryer system for waste liquid processing. PLC will be control the movement of the motor for drum of dryer, heating system, water circulation in the wet scrubber system, vacuum cleaner and smoke systems. All these systems are connected by PLC and working by arranged the setting time of system. The first process, PLC will activate the motion system of motor to drive the dryer drum rotating to left or right side. Then the burner is active for heating the drum of dryer. Effect in this process made smoke and dust happen in the rotary dryer system. The pump automatically will be activating to spray water on a wet scrubber system to catch the dust and smoke. Dust and smoke will be inhaled by the blower and flow back into the rotary dryer machine. Therefore there is no smoke and dust flowing into the environment. The results show that the PLC can be control the motion system and processes machine rotary dryer to drying the waste liquid in short time. Such as 20 minutes to 5 liters of liquid waste volume and 30 minutes to 15 liters and made the waste liquid be friendly environment.

Abstract: Microcontroller Arduino Mega and ATmega is a computer chip that needed and developed to control system or process. Microcontroller Arduino Mega and ATmega can be used to temperature control systems [1][2][3], the room lighting control, security control, the hazard warning [4], scheduling, monitoring water flow and dams actuator door and etc. Most studies on the microcontroller is focused on the functional capability of a microcontroller to read or measure the object. In addition to aspects of good function, microcontroller must have a high sensitivity in order to avoid delay or in-accuracies in the sensor reading measured object such as temperature. Microcontrollers has some advantages and disadvantages of the process accuracy depends on the processor and the ability microcontroller. In this paper focuses on the measurement errors that occur on microcontroller Arduino Mega and ATmega 8535 with a temperature sensor LM 35 and hygrometer digitizes dt05 for the application process cooling and heating sea water controls. The volume of sea water is measured is 3 to 35 litters with a temperature set point 28°C of lower temperatures above 25°C and 31°C. The results show that the maximum error obtained by using microcontroller Arduino Mega is 1,32°C or 13,2 mV and ATmega 8535 is 0,2°C or 2 mV. Also the microcontroller Arduino Mega is more suitable for control temperature measurement in the process of heating and cooling sea water.

Abstract: This paper focuses on the simulation of Beyond Visual Range (BVR) Air Combat using calculation of Probability of Kill (PK) and Supremacy to analyze the effectivity of the tactics and strategies. The developed simulation program is expected to be used as a means of developing tactics, weapons systems evaluation and to support other air combat system applications. The simulation system can be utilized so that strategy for using weapons and better tactics for maneuver can be determined and formulated in the face of an aerial battle. The simulation illustrates how an aerial battle in a 2D plane took place. The battle occurs between two sides and can also cover case of many against many air battle. Fighters maneuver will be generated based on logic and defined tactic by providing input in the form of initial conditions. Formulation / functions, parameters and variables influencing the fighter effectiveness will be taken into account. These elements are modelled using a dynamic and open scenario approach. The simulation used a method called 'Missile Launch Envelope Model' for computing PK of missile along its way to the target. Simulation results for one versus one and many versus many cases show that the developed system can produce good and relatively realistic prediction of the outcome. Further modification of simulation program include fly out modeling to the missile.

Abstract: Photometric stereo works on recovering the shape and reflectance properties of an object using multiple images taken in variable lighting conditions. In this study, a system has been implemented to construct a height field from 12 images of an object. The algorithm which is able to calibrate the lighting direction, find the normals and color albedo at each pixel have been optimized to compute the surface which best fit the normals. This algorithm was also implemented to the welding product to reconstruct the shape of welding bead.

Abstract: This paper presents an object-oriented modelling approach to production scheduling for FMS. The purpose of this study is to prepare a simulation tool to try a method of production scheduling that allocates jobs to the machines and cutting tools in an FMS. This model is developed by using Pharo as the language software for object-oriented programming through UML system design. This model consists of three types of classes. The first type is the Equipment-class, which related to the physical equipment in the FMS, for example machining-centers, cutting tools, pallet stocker, stacker crane. The second type is the Product-class that related to the information how to process the product. This class has sub-class such as process plan, machining operation and required cutting tools. The third class is the Production Planning and Controlling (PPC) class, which related to create the schedule to equipment. The PPC-class has sub-classes such as the daily order or job, job sequence, job allocation on machine and scheduling methods. A numerical example is provided in this paper to show that the object-oriented model for FMS and production scheduling is verified. The FMS consist of four identical machining centers and eight jobs. Each job has a process plan that requires some specific cutting tool types. The method for production scheduling in this model is Shortest Processing Time (SPT). The production scheduling performance is measured in this model.

Abstract: Algal biofuel is considered as an advanced generation bioenergy fuel which addresses the concerns of the preceding generations of biofuels on crop land competition and water consumption. Microalgae are considered as the only biomass feedstock capable of displacing fossil-fuel based on very high-oil yield per land area and other benefits. The production of biofuels in the Philippines is mandated by its Biofuel Act of 2006 which aims to introduce low-carbon fuels to mitigate greenhouse gas emissions and reduce the dependence on oil imports. The Philippines’ biodiesel production uses solely coconut as biomass feedstock to produce coconut methyl ester (CME). With the mandate to increase the biodiesel blend to 5% by 2015, this adds pressure to the production of CME while battling for the fluctuating price of coconut. Due to the archipelagic geography and tropical climate of the country, abundance of thriving endemic species of microalgae can be found in the country. Hence, algal biofuel presents a viable option to alternatively produce biodiesel in the Philippines. Thus, policies in sustainable production of algal biofuel based on its environmental impact and natural resource consumption must initially be developed and drafted. A life-cycle assessment (LCA) approach was recommended to evaluate the sustainability of algal biofuel production in the country leading to policy development. Prior finalizing the impact assessment of an LCA study, prioritization of impact factors must initially be established and evaluated based on the programs and goals of the government and other stakeholders. LCA studies on algal biofuels were previously conducted overseas. However, the impact assessment of such studies is not applicable for the Philippines. Furthermore, there has been limited LCA study on algal biofuel production in the Philippines. Hence, this study proposes to establish a multi-criteria decision structure of the life-cycle impact factors of algal biofuels specifically for the Philippines and quantifying its priority levels using Analytic Hierarchy Process (AHP). AHP is a multi-criteria decision analysis which quantifies the prioritization weights of the considered impact factors via pairwise comparison method. Survey shall be conducted to various government agencies, the industry, and other research institutions to establish an initial impact assessment of algal biofuels in the country. The initial results revealed priority are given to global warming potential, eco-toxicity, and photochemical ozone depletion, respectively. The results of this work shall aid the policy and decision makers of the country to develop and draft environmental policies and strategic plans for the proliferation of algal biofuels in the Philippines.

Abstract: This paper presents overviews about reliability and maintainability of equipment especially for job-shop manufacturing systems. The job shop industry has the characteristics of a more dynamic production than flow shop industries, where products with a variety of great but small amounts. Its dynamic condition certainly contributes directly to the failure rate and reliability growth of equipment. Therefore, proper maintenance should be done as the reliability improvement. Stages of reliability improvement are reliability modeling, reliability analysis and maintenance optimization. This stage is based on reliability growth of equipment that is indicated the deterioration process of failure components, it can be build from maintenance data history or condition data monitoring.. Cost is often considered in points of a maintenance schedule. This cost was affected by minimizing the negative effects of maintenance and maximizing the benefit of production. The attention at reliability and maintenance optimization is a well researches area until now. This paper presents a brief review of existing reliability and maintenance research. Several reliable methods in this area are discussed and maintenance on job-shop industry as future prospects is investigated. It is shown in this paper that some aspect in the area of maintenance on job-shop industry steel needs to be deeply developed.