Depaiwa, Nattawoot

Preferred name

Depaiwa, Nattawoot

Alternative Name

Depaiwa, N.

Main Affiliation

School of Engineering

nattawoot.de@kmitl.ac.th

Now showing 1 - 8 of 8

Some of the metrics are blocked by your
consent settings
Adaptive PID for controlling a quadrotor in a virtual outdoor scenario: Simulation study
(2013-11-25)
Moonumca, Pisan
;
Yamamoto, Yoshio
;
Depaiwa, Nattawoot
The main purpose of this paper is to develop a robust control methodology for unmanned aerial vehicles such as a quadrotor. A conventional proportional-integral-derivative (PID) controller is augmented with adaptive K<inf>P</inf> or non-adaptive K<inf>P</inf> in a throttle input and the both cases are compared and analyzed. Adaptive K<inf>P</inf> is suitable for a system which is subjected to parameter uncertainty, such as variation in payload or wind speed, as the algorithm is able to adjust the K<inf>P</inf> gain of the PID controller so that they maintain robustness and performance. The performance results of the two controllers when applied to a quadrotor are demonstrated using numerical simulation. © 2013 IEEE.
Some of the metrics are blocked by your
consent settings
The force tracking control of electro-hydraulic system based on particle swarm optimization
(2016-01-01)
Moonumca, Pisan
;
Depaiwa, Nattawoot
This paper presents the optimal gains of backstepping controller by using the particle swam optimization technique. The mathematical model is developed by Newton’s second law, compressible fluid flow and flow rates of valve. The control law is formulated by employing a Control Lyapunov Function. The core feature of this paper is the combination of the backstepping and particle swam optimization for optimal performance of controller. The controller gains are determined in automatic selection gains by minimizing the integral of time multiplied by absolute error function on step input. The fitness value can be guaranteed to the convergence of controller gains. The implementations are separated into two cases which are the real and estimated state feedbacks. The experiment has illustrated to find optimal controller gains. The results are also compared with the tracking response of real and estimated state measures in step and square signal. The results show a better tracking performance by using the strong particle swarm optimization (PSO) algorithm.
Some of the metrics are blocked by your
consent settings
Tool path planning technique for robot plasma spray coating on duct component
(2010-12-01)
Aroonchote, Nattapon
;
Naksuk, Nirut
;
Depaiwa, Nattawoot
;
Yamaura, Hiroshi
The internal plasma spray coating process for multisection shapes tubular, which has been applied by multi-axis robot station, is difficult to generate collision-free tool path manually. Robotic software is very helpful to create a tool path. At this point, a plasma flame should be perpendicular to the coating surface and there should be adequate spraying distance, from 3D CAD model. However, the constraints of both shape and size of spray gun and the tubular cause the collision to occur in certain positions on the motion path. The collision between the tubular with robotic parts or any part of the system is strictly prohibited. Therefore, this thesis studies on collision protection system to detect spraying point on the tool path which is the cause of collision. Furthermore, the researchers find tool path adaptation algorithm in order to automatically modify the spraying point to flee from collision. Moreover, the application also retains a spraying condition to keep the coating surface good as well.
Some of the metrics are blocked by your
consent settings
Tuning PID controller using genetic algorithms for electro-hydraulic system with tracking force control
(2014-01-01)
Moonumca, Pisan
;
Depaiwa, Nattawoot
;
Yamamoto, Yoshio
The aim of this paper is design a controller for force control of an Electro-Hydraulic System and selection of a PID gains are using genetic algorithm. The mathematical model is considered as the Newton second law and compressible fluid flow theory. This paper compares two kinds of tuning methods for PID controller. One is the controller design by the genetic algorithm, second is the controller design by the Ziegler and Nichols method. Each PID gains are tested with step input function, square signal, half-sine signal and half-saw signal. And results show performance index with rise time, settling time and Maximum %OS. It was found that the proposed PID gains tuning by the genetic algorithm is better than the Ziegler & Nichols' method. © (2014) Trans Tech Publications, Switzerland.
Some of the metrics are blocked by your
consent settings
Thermal enhancement in a solar air heater channel using rectangular winglet vortex generators
(2010-01-01)
Depaiwa, Nattawoot
;
Chompookham, Teerapat
;
Promvonge, Pongjet
The forced convection heat transfer and friction loss behaviors for turbulent airflow through a constant heat flux channel solar air heater with rectangular winglet vortex generator (WVG) are experimentally investigated in this work. The rectangular winglet pairs are considered with two different arrangements by pointing upstream (PU) and pointing downstream (PD) of the flow. Ten pairs of the WVGs with various attack angles (a) of 60°, 45° and 30° are mounted on the test duct entrance wall to create longitudinal vortex flows over the tested channel. Measurements are carried out for the rectangular channel air heater of aspect ratio, AR = 10 and height, H = 30 mm with the WVG height, b/H = 0.4 and a transverse pitch ratio, P/H = 1. The flow rate is in terms of Reynolds numbers based on the inlet hydraulic diameter of the channel ranging from 5000 to 23,000. The experimental results show that the solar air heater channel with rectangular WVG provides significantly higher heat transfer rate and friction loss than the smooth wall channel. The use of larger attack angle value leads to higher heat transfer rate and friction loss than that of lower one. The PD-WVGs performs higher heat transfer rate and friction loss than the PU one for similar operating conditions. In comparison, the largest attack angle (α= 60°) of the PDWVGs yields the highest increase in Nusselt number and friction factor while the lowest attack angle (α = 30°) of the PU-WVGs shows the best thermal performance.
Some of the metrics are blocked by your
consent settings
Thermal performance in a tubular heat exchanger with deltawinglets
(2018-08-14)
Tongyote, Pattarapan
;
Promvonge, Pongjet
;
Depaiwa, Nattawoot
;
Jedsadaratanachai, Withada
The paper presents an experimental heat transfer enhancement study in a tubular heat exchanger fitted with delta-winglets. The experimental work was conducted by varying the airflow rate in the test tube having a constant wall heat-flux for turbulent regime, Reynolds number (Re) from 5200 to 23,000. Effects of three pitch ratios (PR=P/D=1.5, 2.0 and 3.0) and two attack angles, α = 45° and 60°, of the winglets at a single blockage ratio (BR=b/D = 0.15) on thermal characteristics are examined. The experimental results show that the winglet-inserted tube yields, respectively, the heat transfer, friction factor and thermal performance in the form of TEF around 1.99-4.08, 4.9-14.3 times higher than the plain tube and 0.85-1.85, depending on the operating condition.
Some of the metrics are blocked by your
consent settings
Flow stress determination of steel tube for hydroformability evaluation
(2013-01-28)
Boonpuek, P.
;
Jirathearanat, S.
;
Depaiwa, N.
This study aims to determine flow stress of a steel tube by using hydraulic bulge test. A new proposed analytical model for analyzing bulge shapes of hydroformed tubes is postulated. Bulge test apparatus designed using FEA simulation of hydroforming and STKM 11A steel tubes are used in the hydraulic bulge test. Bulge heights and internal pressures are measured during bulge testing. Tube thicknesses at vertex of a bulge shape are measured by a dial caliper gauge. Bulge curvatures and contact points are measured by taking digital photos of bulge shapes combined with measurement methods in CAD software. Effective stress - strain relationships are obtained from the newly developed analytical model using those measured values. Flow stress curves obtained from the effective stress - strain relationships are compared with those by other researchers and tensile test. Finite element analysis methods are used to conduct simulation of tube hydroforming using the flow stress curves. Predicted internal pressures versus bulge heights and tube thicknesses are compared with experimental results. Verification of the developed analytical model is presented. The flow stress at neck point of formed tube is determined. © (2013) Trans Tech Publications, Switzerland.
Some of the metrics are blocked by your
consent settings
Flow stress determination of steel tube for hydroformability evaluation
(2013-08-01)
Boonpuek, P.
;
Jirathearanat, S.
;
Depaiwa, N.
This study aims to determine flow stress of a steel tube by using hydraulic bulge test. A new proposed analytical model for analyzing bulge shapes of hydroformed tubes is postulated. Bulge test apparatus designed using FEA simulation of hydroforming and STKM 11A steel tubes are used in the hydraulic bulge test. Bulge heights and internal pressures are measured during bulge testing. Tube thicknesses at vertex of a bulge shape are measured by a dial caliper gauge. Bulge curvatures and contact points are measured by taking digital photos of bulge shapes combined with measurement methods in CAD software. Effective stress-strain relationships are obtained from the newly developed analytical model using those measured values. Flow stress curves obtained from the effective stress-strain relationships are compared with those by other researchers and tensile test. Finite element analysis methods are used to conduct simulation of tube hydroforming using the flow stress curves. Predicted internal pressures versus bulge heights and tube thicknesses are compared with experimental results. Verification of the developed analytical model is presented. The flow stress at neck point of the formed tube is determined. © 2013 American Scientific Publishers All rights reserved.

Depaiwa, Nattawoot

Filters

Settings

Sort By

Results per page