Ismoyo Haryanto

Structural Damage Detection Using Randomized Trained Neural Networks

A computational method on damage detection problems in structures was developed using neural networks. The problem considered in this work consists of estimating the existence, location and extent of stiffness reduction in structure which is indicated by the changes of the structural static parameters such as deflection and strain. The neural network was trained to recognize the behaviour of static parameter of the undamaged structure as well as of the structure with various possible damage extent and location which were modeled as random states. The proposed techniques were applied to detect damage in a cantilever beam. The structure was analyzed using finite-element-method (FEM) and the damage identification was conducted by a back-propagation neural network using the change of the structural strain and displacement. The results showed that using proposed method the strain is more efficient for identification of damage than the displacement.

Optimization of Maximum Lift to Drag Ratio on Airfoil Design Based on Artificial Neural Network Utilizing Genetic Algorithm

. This paper deals with an alternative design method of airfoil for wind turbine blade for low wind speed based on combination of smart computing and numerical optimization. In this work, a simulation of Artificial Neural Network (ANN) for determining the relation between airfoil geometry and its aerodynamic characteristics was conducted. First, several airfoil geometries were generated through transformation of complex variables (Joukowski transformation), and then lift and drag coefficients of each airfoil were determined using CFD (Computational Fluid Dynamics). In present study, the ANN training was conducted using airfoil geometry and its aerodynamic characteristics as input and output, respectively. Therefore, lift and drag coefficients can be directly determined only by giving the airfoil geometry without having to perform wind tunnel experiment or numerical computation. Moreover, the optimization was conducted to obtain an airfoil geometry which gives maximum lift to drag ratio (CL/CD) for specific Reynolds number. For this purpose Genetic Algorithm (GA) was applied as optimizer. The results were validated using commercial CFD and it can be shown that the result are satisfactory with error approximately of 6%.

Speech control of robotic hand augmented with 3D animation using neural network

In this paper, speech control of robotic hand augmented with 3D animation system has been proposed and presented. Artificial neural network is employed for speech recognition method with tansig and softmax transfer function in hidden layer and output layer. Stream processing method is incorporated for processing the input signal in real time. Thirteen features in frequency domain and time domain that are commonly used in the EMG analysis are utilized in this system. To reduce the influence of noise, voice in noisy environment in the room is recorded as training data set. From the experimental results in offline speech recognition, ANN can recognize the voice command with very high accuracy. In the online real time speech recognition incorporating stream processing, the recognition accuracy decreased about 10%. The proposed speech control of robotic hand augmented with 3D animation is reliable enough with noisy environment.

Intelligent Bearing Diagnostics Using Wavelet Support Vector Machine

This paper deals with implementation of intelligent system for fault diagnostics of rolling element bearing. In this work, the proposed intelligent system was basically created using support vector machine (SVM) due to its excellent performance in classification task. Moreover, SVM was modified by introducing wavelet function as kernel for mapping input data into feature space. Input data were vibration signals acquired from bearings through standard data acquisition process. Statistical features were then calculated from bearing signals, and extraction of salient features was conducted using component analysis. Results of fault diagnostics are shown by observing classification of bearing conditions which gives plausible accuracy in testing of the proposed system.

Performance of a compression ignition engine four strokes four cylinders on dual fuel (diesel–LPG)

The needs of energy in Indonesia show significant increase every year especially are non-renewable energy. Fossil fuel are non-renewable energy resources that usually used in the combustion engine. The limited resource of fossil fuels means reducing fuels consumption has been vital in case of engine development. There are two type of combustion engine that widely used i.e. compress ignition and spark ignition engine. Compress ignition engine usually has better thermal efficiency than spark ignition engine. Compress ignition engine usually used diesel fuel which are fossil fuel as primary fuel. Dual fuel method has been used to improve fuel consumption in diesel engine. Dual fuel has advantages in better thermal efficiency, power, and CO emission. In this research, dual fuel is used in C223 diesel engine with Liquid Petroleum Gas (LPG) as secondary fuels. Dual fuel mode is tested by varying LPG concentration at 35%, 45%, and 75% with various speed at 1500,1800,2100, and 2700 rpm. Engine performance such as fuel consumption, thermal efficiency, and power are being investigated. The results show that brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), and power with dual fuel engine better than single fuel (diesel only). The improvement of BTE are appear with LPG 45% concentration or denoted as G45.The needs of energy in Indonesia show significant increase every year especially are non-renewable energy. Fossil fuel are non-renewable energy resources that usually used in the combustion engine. The limited resource of fossil fuels means reducing fuels consumption has been vital in case of engine development. There are two type of combustion engine that widely used i.e. compress ignition and spark ignition engine. Compress ignition engine usually has better thermal efficiency than spark ignition engine. Compress ignition engine usually used diesel fuel which are fossil fuel as primary fuel. Dual fuel method has been used to improve fuel consumption in diesel engine. Dual fuel has advantages in better thermal efficiency, power, and CO emission. In this research, dual fuel is used in C223 diesel engine with Liquid Petroleum Gas (LPG) as secondary fuels. Dual fuel mode is tested by varying LPG concentration at 35%, 45%, and 75% with various speed at 1500,1800,2100, and 2700 rpm. Engine performance such as...

Development of Unmanned Aerial Vehicle (UAV) ornithopter with wireless radio control

Ornithopter is one of UAV which utilizing bird flying concept as flight mechanism. This research begins with ornithopter design mechanism, mechanical, electrical and control design followed by manufacturing process. Kinematic and experimental analysis is used to obtain data from the ornithopter. Ornithopter design lead to the result of 80 cm wingspan and 333 gr in total weight. From the calculation results, the maximum of 12,9 Hz flapping frequency can be achieved in this mechanism. Based on the experiment, the maximum lift force and thrust are 2.4447 N and 1.8608 respectively. The estimated surface area using CAD software is 0.11 m2 and the calculated wing load is 3.03 kg/m2.

Sliding mode control for therapeutic pool model control system

In this study we consider the robust control of a therapeutic pool model using Sliding Mode Control (SMC). Therapeutic pool is a warm water pool used for stroke therapy. It makes exercises for stroke patients easier than done outside water because of the water buoyant force which reduces human weight. The therapeutic pool which is designed in this study has two inlets and an outlet for drainage. The first inlet is for the hot water flow and the second is for the cold water flow. The two water flows are mixed in the therapeutic pool. The controlled variable is the mixed water temperature in therapeutic pool. Unsteady thermodynamics and mass balance are used to mathematically model the therapeutic pool. The SMC controller is designed to reject disturbances due to heat transfer from the mixed water to surrounding through the contacting surface between water and the free air stream. The usefulness of this technique is illustrated with a simulation. Desired temperature of therapeutic pool is successfully reached and maintained steady. The performance of SMC controller is compared to conventional PID (Proportional Integral Derivative) controller and the neural model of the conventional one.

KETAHANAN BALISTIK LEMBARAN BAJA PADA BERBAGAI SUDUT TEMBAK

Results of study on the performance of 0.4 mm mild steel plate when impacted by 4.5 mm diameter steel ogive-shaped projectile at 45 o , 60 o (oblique impact) and 90 o (normal impact) angles of attack are presented. The projectiles were fired at highest velocity using air riffle gun. The target-holding fixture was located at a distance of 2 m from the gun. Experimental results show that steel plate provides protection at 45 o and 60 o obliquity, but fails to provide protection at angle of attack of 90 o (normal impact)

Vibration Gear Fault Diagnostics Technique Using Wavelet Support Vector Machine

Intelligent diagnostics tool for detecting damaged bevel gears was developed based on wavelet support vector machine (WSVM). In this technique, the existing method of SVM was modified by introducing Haar wavelet function as kernel for mapping input data into feature space. The developed method was experimentally evaluated by vibration data measured from test rig machinery fault simulator (MFS). There were four conditions of gears namely normal, worn, teeth defect and one missing-teeth which has been experimented. Statistical features were then calculated from vibration signals and they were employed as input data for training WSVM. Fault diagnostics of bevel gear was performed by executing classification task in trained WSVM. The accuracy of fault diagnostics were evaluated by testing procedure through vibration data acquired from test rig. The results show that the proposed system gives plausible performance in fault diagnostics based on experimental work.