Agfianto Eko Putra

Quadrotor flight stability system with Routh stability and Lyapunov analysis

UAV (Unmanned Aerial Vehicle) can fly autonomously or be controlled remotely by a pilot. Quadrotor as one type of UAV has been widely implemented in various needs. Its system design has a lot of control techniques involved. The design starts with the physical modeling. Quadrotor physical modeling is modeling based on the laws of physics as a theory and mathematical modeling of physical interpretation. The problem arises when actual plants are not fit with mathematical models that are used as the control design before. Such discrepancy arises because of external interference, plant parameters, and dynamics models that are nonlinear. If control systems are not designed to deal with non-linear interference, it is difficult to us to maintain quadrotor flight. Therefore, we need control methods that can be applied to linear and nonlinear systems. Routh Stability can be used to generate PID (Proportional Integral and Derivative) constants as a linear control method by using a Ziegler-Nichols. Lyapunov as a meth...

A Survey of Pedestrian Detection in Video

Pedestrian detection is one of the important topics in computer vision with key applications in various fields of human life such as intelligent vehicles, surveillance and advanced robotics. In recent years, research related to pedestrian detection commonplace. This paper aims to review the papers related to pedestrian detection in order to provide an overview of the recent research. Main contribution of this paper is to provide a general overview of pedestrian detection process that is viewed from different sides of the discussion. We divide the discussion into three stages: input, process and output. This paper does not make a selection or technique best method and optimal because the best technique depends on the needs, concerns and existing environment. However, this paper is useful for future researchers who want to know the current researches related to pedestrian detection.

The use of video processing for quadrotor flight stability control monitoring

The quadrotor is one kind of Unmanned Aerial Vehicles (UAV). Quadrotor has the ability to hover with minimal translational velocity approaching a stationary state. This capability is supported by the four rotors. These rotors are used to lift the Quadrotor to fly. These rotors are placed on all four sides of the tip of Quadrotor. In order to fly with good stability, we can use an IMU sensor (Inertial Measurement Unit). Imu sensor consists of some DOF (degrees of freedom) sensors, such as 3-axis accelerometer sensor, 3-axis gyroscope sensor, 3-axis magnetometer sensor, and so on in accordance with the needs of flight. To test the stability of Quadrotor can be done by utilizing the video and image processing methods. This processing act as the ’eyes’ of Quadrotor. Sobel method as one of the image processing algorithms can be used to read the edges of the object. This method can measure the level of stability fly. But before reading the results of the edge must first be converted to black and white format. O...

PID self tuning control based on Mamdani fuzzy logic control for quadrotor stabilization

Quadrotor as one type of UAV have the ability to perform Vertical Take Off and Landing (VTOL). It allows the Quadrotor to be stationary hovering in the air. PID (Proportional Integral Derivative) control system is one of the control methods that are commonly used. It is usually used to optimize the Quadrotor stabilization at least based on the three Eulerian angles (roll, pitch, and yaw) as input parameters for the control system. The three constants of PID can be obtained in various methods. The simplest method is tuning manually. This method has several weaknesses. For example if the three constants are not exact, the resulting response will deviate from the desired result. By combining the methods of PID with fuzzy logic systems where human expertise is implemented into the machine language is expected to further optimize the control system.

Optimizing control based on ant colony logic for Quadrotor stabilization

Quadrotor as one type of UAV (Unmanned Aerial Vehicle) have the ability to perform Vertical Take Off and Landing (VTOL). It allows the Quadrotor to be stationary hovering in the air. PID (Proportional Integral Derivative) control system is one of the control methods that are commonly used. It is usually used to optimize the Quadrotor stabilization at least based on the three Eulerian angles (roll, pitch, and yaw) as input parameters for the control system. The three constants of PID can be obtained in various ways or methods. However, to produce a robust control, we need a method that can optimize the PID components. Ant Colony Optimization (ACO) is one of PID controller optimization method which adapted by ant colony ability to find the shortest way from their nest to food. Some ACO parameters are number of ants, parameters, and pheromone constant for pheromone. Pheromones are the values given by the ants when they use the road.

Efficient K-Nearest Neighbor Searches for Multiple-Face Recognition in the Classroom based on Three Levels DWT-PCA

The main weakness of the k-Nearest Neighbor algorithm in face recognition is calculating the distance and sort all training data on each prediction which can be slow if there are a large number of training instances. This problem can be solved by utilizing the priority k-d tree search to speed up the process of k-NN classification. This paper proposes a method for student attendance systems in the classroom using facial recognition techniques by combining three levels of Discrete Wavelet Transforms (DWT) and Principal Component Analysis (PCA) to extract facial features followed by applying the priority of k-d tree search to speed up the process of facial classification using k-Nearest Neighbor. The proposed algorithm is tested on two datasets that are Honda/UCSD video dataset and our dataset (AtmafaceDB dataset). This research looks for the best value of k to get the right facial recognition using k-fold cross-validation. 10-fold cross-validation at level 3 DWT-PCA shows that face recognition using k-Nearest Neighbor on our dataset is 95.56% with k = 5, whereas in the Honda / UCSD dataset it is only 82% with k = 3. The proposed method gives computational recognition time on our dataset 40 milliseconds.

EEG-based microsleep detector using microcontroller

Drowsiness has symptoms which are itchy eyes, slow eye blink movement, smaller pupils, yawning and even trembling body. But the driver ignores it when the body send one of those signals often. The impacts which can occur to the driver, such as make incorrect decision while driving, could happen and lead to the most car accident reason. Therefore, the system which can provide an alarm when the driver feels drowsiness, fatigue or even microsleep is required. The way to detect microsleep when it occurs is to use the Electroencephalograph (EEG) brainwave. The system uses the one channel EEG Sensor device developed by Neurosky Mindwave which can provide eight brainwave signal such as Delta, Theta, Low Alpha, High Alpha, Low Beta, High Beta, Low Gamma, and Mid Gamma. On the other hand, attention and relaxation value can be generated as well. This prototype system tested by the car driver achieved its purpose of detecting microsleep event and alerting the driver by the alarm.

Pemodelan Generator Uap Berbasis Jaringan Saraf Tiruan dengan Algoritme Pelatihan BPGD-ALAM

Steam generator is unit plant which has nonlinear and complex system with multiple-input-multiple-output (MIMO) configuration which is hard to be modeled. Whereas, steam generator model is very useful to create simulation such as operator training simulator (OTS). The purpose of this research is to obtain model of steam generator which has 8 output parameters and 9 input parameters based neural network (NN) with BPGD-ALAM training algorithm. Data had been taken from steam generator of PT. Chevron Pacific Indonesia, Duri and it is divided into three types, i.e training data, validation data and testing data. Training data was used to obtain model for each ouput through training process. Verification model is also done for each epoch using validation data to monitor training process whether overfitting occurs or not. Eight NN model of each output which is obtained from training and verification, is tested using testing data for getting its performance. From the reseach results, architecture of neural network models are obtained with various configuration for each output with RMSE value under 9.71 %. It shows that model which has been obtained, close with steam generator real system.

Real-time operating system implementation on OBC/OBDH for UGMSat-1 sequence

On-Board Computer or On-Board Data Handling (OBC/OBDH) has an important role as a manager for data housekeeping and communication handling between OBC/OBDH to its TTC (Telemetry and Telecommand) and EPS (Electronic Power System) subsystems in the satellite system. In order to operate according to the satellite sequence, the RTOS (Real-Time Operating System) is implemented on the UGMSat-1. The CooCox CoOS is used as an RTOS, which is has three tasks which are Condition-Check, Housekeeping, and Communication Task. The highest priority among the tasks on the system is Communication Task. The experiment proves that three tasks can run well with the time cycle of 2.034, 30.047, and 1.017 seconds for Condition-Check, Housekeeping, and Communication task respectively. The result of overall experiments shows that the OBC/OBDH can manage data packets and sent them to Ground Station.

Satellite tracking control system for UGM ground station based on TLE calculation

UGM ground station requires a satellite tracking control system that can follow the movements of the satellite. The system proposed in this study is relying on the calculation of Two Line Elements (TLE), the reason is that the data TLE has a subtle error. The compass sensor is used to ensure accuracy; the results were evaluated using a protractor, and about 99%. Moreover, this system is also tested to receive images from NOAA satellites using the RTL-SDR and Yagi antennas. In general, this system can follow the motion of the satellite well.