Abstract: This paper presents the development of mathematical model and designing a temperature control system for an industrial preheating furnace. In the first part of the paper, the simulation model was developed based on thermodynamics principles, energy-mass balance and semi-empirical relations. The parameters of developed models were defined with respect to available operational and geometrical data from real system. In the second part, an appropriate control system was designed for regulating the preheating furnace temperature. A fuzzy logic controller and a feedback/feedforward controller were employed for operating in coordination with each other to maintain the process outlet temperature around 360 oC. Simulation results show the capability of the designed control system to regulate the furnace outlet temperature at different operating conditions and in the presence of disturbances.
Abstract: Manufacturing is one of the main source of income for a developing country, like Malaysia. Start from the beginning of need in the market, a new concept of product is created. From the initial idea based on a need, this idea is hard to be understood if not presented in any form of drawing or prototype. So, computer-aided design (CAD) has the greatest role in helping to visualise the initial concept of a design with presenting the idea in a graphical view. However, this type of data cannot be used directly for the manufacturing process and normally intervention of human effort is needed to define all the manufacturing features from the component drawing again. This work is laborious if not assisted by computer technology. As a result, this paper aims to design a system and database which has the ability to extract geometrical features from drawings and identify all the manufacturing features which is useful for manufacturing process. This project takes a neutral drawing format, ISO 10303-203, as the input of the system. Then, a mechanism which consists of manufacturing feature extraction and feature recognition will be implemented and lastly, a new form of manufacturing feature-based data, ISO 10303-224 will be acquired for the subsequent manufacturing process.
Abstract: In order to improve the quality of cascade multilevel inverter’s output voltage, this paper introduces an optimization harmonic elimination control technique. The harmonic of cascade multilevel inverter is controlled by the switch angels of inverter units. Through this technique, switch angels eliminate the low and middle frequency harmonic compositions and at the same time make total harmonic distortion rate of cascade multilevel inverter low are found. The correctness and accuracy of optimization harmonic elimination control technique are validated by simulation and experiment model.
Abstract: Friction is an undesired nonlinear phenomenon that reduces position and tracking accuracy in machine tools application. This paper focuses on development of control technique to compensate friction force at motion reversal of a drive system that generates quadrant glitch phenomenon thus improving tracking accuracy. Sliding Mode Control (SMC) is designed to compensate friction. The Generalized Maxwell-Slip (GMS) friction model is applied for numerical analysis. The performance of the controller is analysed based on the reduction in the quadrant glitches magnitude. The performance of the SMC controller is compared with the classical PID controller. Results show that SMC controller yields the smallest quadrant glitch magnitudes.
Abstract: In this paper, a review of the historical development of fault- tolerant control, some proposals for the terminology in the field of supervision, fault detection and tolerance control are presented. The directions in which the subject is going are summarised and some pointers are given as to the likely issues and where new research effort is required. The paper provides a basic literature review covering most areas of fault-tolerant control of single-link flexible manipulator system.
Abstract: This paper presents about the development of an Antilock Braking System (ABS) using quarter vehicle model and control the ABS using different type of controllers. Antilock braking system (ABS) is an important part in vehicle system to produce additional safety for drivers. In general, Antilock braking systems have been developed to reduce tendency for wheel lock and improve vehicle control during sudden braking especially on slippery road surfaces. In this paper, a variable structure controller has been designed to deal with the strong nonlinearity in the design of ABS controller. The controllers such as PID used as the inner loop controller and Fuzzy Logic as outer loop controller to develop as ABS model to control the stopping distance and longitudinal slip of the wheel.
Abstract: This paper proposes a method of developing ladder logic diagram for PLCs via S-method (a structured method of programming routines). From flexible manufacturing industry point of view, engineers can easily understand the operation of the complicated system and have better control on industrial automation system by applying S-method. By practicing this, highly dependent on vendor for operating the system also can be eliminated. This paper describes detailed steps of the method that converts from description of the system to a ladder logic diagram involving a series of systematic steps. A case study on pick and place section, the KUKA system which is implementing the S-method is discussed in paper.
Abstract: As a typical large rotary dual-drive device, three-car dumper is an essential and important equipment of raw materials storage and transport in the power, chemical industry, metallurgy, ports and other industries. It has some characters such as massive structure, heavy bearer, low-frequency running, frequent starting and braking and mechanical center of gravity which often shifts. The low-speed drive system has some working characteristics such as heavy loads, heavy shocks, low speed, poor working conditions, often breaking teeth and so on, so we propose a reverse design method for low-speed overloaded open gears through using design principles of reverse transformation. By using product reverse technology, we make the parameter design of low-speed and overloaded open gear pairs of Delafu dumper localization, so it extends the service life of gear pair and parts replacement period.
Abstract: The natural ventilation in a heating workshop with different horizontal arrangement of heat source was numerically simulated based on computational fluid dynamics (CFD) method. Realizable k- turbulent model was used to calculate the air flow and temperature distribution. Simulation results showed that the horizontal arrangement of the heat source in the workshop influenced heavily the air flow and temperature distribution. When the heat source was placed at the workshop centre, the heat distribution factor was minimal, the average air temperature at operation zone was lowest and the hot air exhausting velocity was highest, the air flow field and temperature distribution was reasonable for the natural ventilation. When the heat source was placed to be close to the air inlet opening, the fresh air would travel a short path and directly rise to exit and the fresh air did not reach to the right part of the workshop, leading to a possible accumulation of pollutant emission there. When the heat source was placed at the right side of the workshop, the benefit would be that the possible pollutant could be taken away by the air flow, however, the ventilation rate decreased.
Abstract: In this paper, AZ31B drawing test was carried out under the mechanical press with crank-slide mechanism. The influence of drawing temperature and drawing clearance on the wall thickness of AZ31B drawn parts was studied through testing. Some conclusions were drawn, which are: with the increase of drawing temperature, minimum wall thickness ( Tmin ) and maximum wall thickness ( Tmax ) of AZ31B drawn parts substantially decreased; with the increase of drawing clearance, Tmin and Tmax of AZ31B drawn parts increased.