Abstract: Literature review shows that, most of the linear controllers proposed for control of a Two-Wheeled Inverted Pendulum (TWIP) mobile robot are based on dynamic models that are linearized around a single operating point. Thus, this paper presents the controller design for a TWIP mobile robot based on its multiple operating point linearized model. The nonlinear dynamical equations of motion of the TWIP mobile robot were firstly obtained. The nonlinear equations were then linearized around different operating points resulting in a number of linear models with each represented a local region of the original nonlinear system. Based on the multiple operating points linearized models a state feedback control scheme was proposed using pole placement technique for balancing and tracking control of the TWIP mobile robot. The performance of the proposed controller investigated in terms of reference command tracking, parameter variation and external disturbance rejection via simulations. The simulation result shows the effectiveness of the proposed control scheme.

Abstract: Modeling and simulation of engineering production systems is one of the major concerns of productivity engineers for the establishment of productivity standards in virtually all functional areas of an organization. There are several activities in a metal fabrication system, such as aluminium rolling mills, but the maintenance function is a major area, if optimised, can ensure its profitability. The maintenance functions have several parameters to monitor and measure and there is the need for an integrated approach to optimize the basket of parameters measured. This paper is a study of the maintenance fabrication system with a view at identifying suitable approaches in integrated and systematic maintenance productivity measurement and creating models for optimising total productivity. Discussing several approaches of maintenance productivity measurement it shows how understanding the impact of plant failure and repair/service distributions assists in enhancing maintenance productivity using discrete event system simulation.

Abstract: In the industry today, continuous attempts to realize optimal efficiency and increased productivity have spawned much progress in the use of intelligent automated devices and machines to perform various operations and tasks. The thrust of this work is to present the development of a three-degree-of-freedom revolute robot manipulator amenable to pick-and-place operations in the industry. Appropriate kinematic equations of the manipulator are obtained, and then used to develop algorithms for locating predetermined positions of a small object in a customized workspace. An Arduino-based controller circuit is built to implement the algorithms, and servomotors are used to carry out independent joint control of the manipulator. The positions of the object are identified with the aid of light-dependent resistors (LDR). Besides, in order to aid easy fabrication of links and overall system assembly, a 3D model of the manipulator is designed. The results of the work, showing effective and satisfactory operation of the manipulator, are presented.

Abstract: The objective of this study is to investigate the application of various techniques of adaptive control in industrial processes with the temperature maintained between 2°C to 8°C for the thermoelectric refrigerator (TER) system for vaccine chamber. The system is nonlinear and exhibits varying model parameters, hence the object of the study is to investigate control strategies that are not based on detailed advance plant knowledge but allow adaptation of the controller changing the system dynamics. The mathematical model has been identified for the TER system using input-output real-time system. The black box modelling approach is appropriately chosen since this is needed for the implementation of adaptive control. The TER system has been identified using Recursive Least Squares (RLS) method. A second order model is use to represent the system. The validation procedures show that the derived model is indeed a good enough representation of the TER system. Adaptive self-tuning control approaches of pole assignment with several variations have been considered.

Abstract: Web tension/speed control is a very important issue to web handling machines. In this paper, an adaptive sliding mode (ASM) control strategy is proposed for winding process control. It aims to force system state to move to and maintain on the defined sliding surface without fluctuation. An embedded neural fuzzy approximator is developed to improve the transient response and enhance web tension control; an A-function is suggested to improve control operation stability; and the controller’s convergence is improved by a hybrid training algorithm. The effectiveness of the developed ASM control is verified by experimental tests. Test results show that the developed ASM can provide stable control operations and outperforms the classical SM control; it can effectively suppress tension and speed fluctuations and adaptively accommodate for system uncertainty.

Abstract: This paper presents the boilingcharacteristics of the refrigerant mixture of R744/R1270 flowing through the horizontal smooth tube of 4mmID and 5mm OD. Experimental results on the heat transfer coefficient, inner wall temperature, exergyand Nusselt number of refrigerant mixture of R744/R1270 are presented. The refrigerant mixture R744/R1270 in combinations of 25/75, 50/50 and 75/25 is studied at different mass flux conditions. It is found that the mixture combination of R744/R1270as75/25 at all mass flux except at a mass flux of 60 kg/ m2 s gives maximum heat transfer.

Abstract: This study discusses the performance and exhaust emissions of a vehicle fueled with low content alcohol (methanol) blends and pure gasoline. In this study, experiments have been done to measure the performance and emissions of a 4-stroke S.I. Engine, one by using the commercial imported gasoline, another by using the gasoline-methanol blends. The engine is run at different loads and methanol blending percentages . It is found that increasing the blending percentage reduces the emitted concentration of carbon oxides and HC . However it is found that break power and break thermal efficiency are increased with increasing methanol blending percentage due to higher cylinder temperatures. The results showed that use of 10% volume of methanol blending with the gasoline appears to be a good option for replacing any oxygenate additives in the gasoline, where the CO, CO2, and HC are minimum and the fuel consumption of the blend is lower than of the commercial gasoline.