Thana Radpukdee

Robust Adaptive PID Controller for a Class of Uncertain Nonlinear Systems: An Application for Speed Tracking Control of an SI Engine

The sliding mode control (SMC) technique with a first-order low-pass filter (LPF) is incorporated with a new adaptive PID controller. It is proposed for tracking control of an uncertain nonlinear system. In the proposed control scheme, the adaptation law is able to update the PID controller online during the control process within a short period. The chattering phenomenon of the SMC can be alleviated by incorporation of a first-order LPF, while the robustness of the control system is similar to that of the sliding mode. In the closed-loop control analysis, the convergence condition in the reaching phase and the existence condition of the sliding mode were analyzed. The stability of the closed-loop control is guaranteed in the sense of Lyapunov’s direct method. The simulations and experimental applications of a speed tracking control of a spark ignition (SI) engine via electronic throttle valve control architecture are provided to verify the effectiveness and the feasibility of the proposed control scheme.

Motorcycle On-Road Driving Parameters Influencing Fuel Consumption and Emissions on Congested Signalized Urban Corridor

This study aims to find the on-road driving parameters influencing fuel consumption and emissions of motorcycle driving on a congested signalized urban corridor. A motorcycle onboard measurement system was developed to measure instantaneously and continuously record on-road driving data, including speed-time profile, emissions, and fuel consumption, by the second. The test motorcycles were driven by 30 sample motorcyclists on a signalized urban corridor in Khon Kaen City, Thailand, to collect their on-road driving behavior during the morning peak period. Cluster analysis was applied to analyze collected driving data and to categorize the drivers by level of fuel consumption and on-road driver behavior. The on-road driving parameter influencing fuel consumption and emissions was then determined. Results revealed that proportion of idle time significantly influenced fuel consumption and emissions of motorcycle driving on a congested signalized urban corridor, though aggressive driving behavior, hard acceleration and deceleration, did not have the same kind of influence.

Development of on Board Motorcycle System to Measure on Road Driving Pattern

This study developed an onboard system to measure on road driving pattern for a motorcycle. The main components of the developed system consist of a magnetic wheel speed sensor for measuring speed of the motorcycle and a data logger. The developed data logger consists of a microcontroller, memory storage and data display panel for processing and recording the on road speed-time data. The developed system was validated to measure and correctly record speed per time interval. The developed onboard system will be applied by installing on driven motorcycles for recording a speed-time data that will be used to develop the motorcycle driving cycle.

Many-Objective Optimisation of Trusses Through Meta-Heuristics

A truss is one of the most used engineering structures in daily life due to several advantages. A process for truss optimisation is usually set to minimise its mass while structural safety constraints are imposed. This design problem always leads to structures with less reliability since the solution is generally on the borderline of structural failure. Such a phenomenon can be alleviated by adding effects of all possible load cases with safety factors to design constraints. Alternatively, the design problem should be many-objective optimisation assigned to optimise mass and reliability indicators for all load cases. This paper is the first attempt to study such a design process. A number of many-objective meta-heuristics are employed to solve the test problems for many-objective truss optimization where their performances are compared.

Development of On-Road Exhaust Emission and Fuel Consumption Models for Motorcycles and Application through Traffic Microsimulation

This study developed on-road exhaust emission and fuel consumption models for application in traffic microsimulations to estimate motorcycle emissions and fuel consumption in an Asian developing city. The motorcycle onboard measurement system was developed to instantaneously measure and continuously record on-road driving data, including the speed-time profile, exhaust emissions, and fuel consumption per second. The test motorcycle was driven on roads around Khon Kaen City, Thailand, to collect on-road driving data during the morning peak hours for a total of 112 hours. The collected on-road driving data were applied to develop on-road exhaust emission and fuel consumption models using regression analysis. The models were developed with high correlations among the amount of exhaust emissions and fuel consumption and the instantaneous speed and acceleration rate. The developed models were applied with a traffic microsimulation to evaluate the exclusive zone for motorcycles stopping at a signalized intersection. The evaluation results reveal that it could improve the level of intersection service by decreasing travel times, delays, and queue lengths at intersections, as well as by reducing the fuel consumption and emissions of vehicles travelling through intersections compared with these values under the existing conditions.

Climate control system of a poultry house using sliding mode control

This work focuses on the application of Sliding Mode Controller with uncertainty learning and control gain estimation techniques to provide the desired climatic conditions in the poultry house. The nonlinear dynamics mathematical model was derived from physical governing equations of the industrial scale system and was validated under the hot and humid climate conditions of Thailand, along with fluctuation of temperature and humidity of the ambient air. The control law was developed by employing Multi-Sliding Modes control scheme. The uncertainty learning and compensation technique were applied to eliminate the unknown nonlinear characteristic and disturbances of the system. The simulation result indicated that the proposed controller was able to improve the control performance of the plant comparing to traditional on/off control, and robust adaptive PI control law provided in previous work. The saturation of control input did not occur while the system response showed fluctuation-free.

Engine Map and Optimal Operation Path Construction for an Engine-CVT Powertrain System

Rising fuel costs increase the importance of CVT powertrains in the automotive industry. Their benefit is that they allow an engine to operate at any condition which motivates development of fuel economy mode control strategies. In this work, an engine map is multiplied by the efficiency of a hydrostatic continuously variable transmission (HCVT). Therefore, the map is pictured in a 3D Cartesian space which is functioned into 3 parameters of indicated engine torque, engine speed, and transmission ratio. Operation of the engine powertrain system can be set to support any required power and speed of the vehicle at the highest efficiency point. The study examines a 900 cc. gasoline engine connected to the HCVT. To generate the operating range of the engine, the engine speed and hydraulic pressure were controlled by an electronic throttle and pump swash plate variation, respectively. The operating range is 3.353 - 10.442 kW. This power corresponds to a vehicle ground speed of 43.065 61.488 km/hr through a gear ratio of 0.5-1.5. Consequently, the system efficiency map was created and then used to construct the best operating path according to the required driving cycle. The points on the path were selected by the concept of the highest overall efficiency in the 3D map. As a result, the optimal operation path was found by connecting each point which is directed to the best solution for vehicle operation.