GURU v2.0: An interactive Graphical User interface to fit rheometer curves in Han's model for rubber vulcanization

A GUI software (GURU) for experimental data fitting of rheometer curves in Natural Rubber (NR) vulcanized with sulphur at different curing temperatures is presented. Experimental data are automatically loaded in GURU from an Excel spreadsheet coming from the output of the experimental machine (moving die rheometer). To fit the experimental data, the general reaction scheme proposed by Han and co-workers for NR vulcanized with sulphur is considered. From the simplified kinetic scheme adopted, a closed form solution can be found for the crosslink density, with the only limitation that the induction period is excluded from computations. Three kinetic constants must be determined in such a way to minimize the absolute error between normalized experimental data and numerical prediction. Usually, this result is achieved by means of standard least-squares data fitting. On the contrary, GURU works interactively by means of a Graphical User Interface (GUI) to minimize the error and allows an interactive calibration of the kinetic constants by means of sliders. A simple mouse click on the sliders allows the assignment of a value for each kinetic constant and a visual comparison between numerical and experimental curves. Users will thus find optimal values of the constants by means of a classic trial and error strategy. An experimental case of technical relevance is shown as benchmark

Ground tyre rubber and post-consumer polyethylene reactive injection moulded composite

Post consumer tyres continue to present the community with challenges for their safe and sustainable disposal. They also present an opportunity to divert a significant waste stream in to a valuable resource. This thesis looks into one possible method to recycle post consumer tyres and high density polyethylene won from curb side collection of milk packaging. The study investigates the use of a bromomethyl phenol resin as the basis of a compatibilization chemistry enabling a bond to be formed between the ground tyre rubber particle and the polyethylene matrix. It builds upon the seminal work of Coran & Patel in developing thermoplastic vulcanites and the more recent work of Liu and colleagues. Unlike previous investigators, this work employed a single process to both compound the composite component materials and to form the end product. This single process was carried out using an injection moulding machine that was modified by the addition of a number of automated hoppers that delivered the composite component materials and compatibilization chemistry to the moulder’s screw. Through this system of reactive injection moulding it was demonstrated that both the composite material and product could be formed in a single process. Investigation of the mechanical properties of ground tyre rubber and polyethylene composites using tensile testing techniques was undertaken. The results of tensile testing indicated that the particle matrix bond was formed only when dicumyl peroxide was included in the compatibilization chemistry. This was established from the observation of dense arrays of fibrils joining the rubber particles to the HDPE matrix in samples that had been tested to ultimate failure. The particle matrix bond was not formed when dicumyl peroxide was not present. An investigation was undertaken using X-ray photo spectrometry to examine the bonding chemistry. This revealed the presence of the carbon oxygen carbon sequence at the particle surface when dicumyl peroxide was a component of the compatibilization chemistry. The presence of this sequence of atoms is a necessary, but not sufficient, condition for the Chroman Ring structure to be present in the bond. The presence of this structure would give rise to a more tenacious bonding between particle and matrix than would normally be achieved through either carbon carbon or carbon sulphur cross linking mechanisms. The identification of the Chroman Ring structure in ground tyre rubber and polyolefin composites has not previously been reported in the literature. The contribution made by the particle matrix bond to the overall performance of the composite was investigated using non linear explicit finite element analysis. Two models for the composite were developed, a simplified single particle model which was used to verify the interaction between particle and matrix and also to provide a development environment for a model of the particle matrix bond. Subsequently, a more complex multi particle model was developed which was of higher fidelity to the formed composites. Through the use of these models it has been deduced that the bond achieved between particle and matrix had a strength of approximately 1MPa and that, for the properties of the particle and the matrix materials, the bond was likely to fail significantly before the composite attained peak loading conditions. The use of these models also revealed the probability that the matrix material may have been significantly modified through cross linking during the forming process and that this may have accounted for some of the perceived improvement in the materials’ performance

A Review of Resonant Converter Control Techniques and The Performances

paper first discusses each control technique and then gives experimental results and/or performance to highlights their merits. The resonant converter used as a case study is not specified to just single topology instead it used few topologies such as series-parallel resonant converter (SPRC), LCC resonant converter and parallel resonant converter (PRC). On the other hand, the control techniques presented in this paper are self-sustained phase shift modulation (SSPSM) control, self-oscillating power factor control, magnetic control and the H-∞ robust control technique

OBSERVER-BASED-CONTROLLER FOR INVERTED PENDULUM MODEL

This paper presents a state space control technique for inverted pendulum system. The system is a common classical control problem that has been widely used to test multiple control algorithms because of its nonlinear and unstable behavior. Full state feedback based on pole placement and optimal control is applied to the inverted pendulum system to achieve desired design specification which are 4 seconds settling time and 5% overshoot. The simulation and optimization of the full state feedback controller based on pole placement and optimal control techniques as well as the performance comparison between these techniques is described comprehensively. The comparison is made to choose the most suitable technique for the system that have the best trade-off between settling time and overshoot. Besides that, the observer design is analyzed to see the effect of pole location and noise present in the system

A Review of Resonant Converter Control Techniques and The Performances

paper first discusses each control technique and then gives experimental results and/or performance to highlights their merits. The resonant converter used as a case study is not specified to just single topology instead it used few topologies such as series-parallel resonant converter (SPRC), LCC resonant converter and parallel resonant converter (PRC). On the other hand, the control techniques presented in this paper are self-sustained phase shift modulation (SSPSM) control, self-oscillating power factor control, magnetic control and the H-∞ robust control technique

State-Feedback Controller Based on Pole Placement Technique for Inverted Pendulum System

This paper presents a state space control technique for inverted pendulum system using simulation and real experiment via MATLAB/SIMULINK software. The inverted pendulum is difficult system to control in the field of control engineering. It is also one of the most important classical control system problems because of its nonlinear characteristics and unstable system. It has three main problems that always appear in control application which are nonlinear system, unstable and non-minimumbehavior phase system. This project will apply state feedback controller based on pole placement technique which is capable in stabilizing the practical based inverted pendulum at vertical position. Desired design specifications which are 4 seconds settling time and 5 % overshoot is needed to apply in full state feedback controller based on pole placement technique. First of all, the mathematical model of an inverted pendulum system is derived to obtain the state space representation of the system. Then, the design phase of the State-Feedback Controller can be conducted after linearization technique is performed to the nonlinear equation with the aid of mathematical aided software such as Mathcad. After that, the design is simulated using MATLAB/Simulink software. The controller design of the inverted pendulum system is verified using simulation and experiment test. Finally the controller design is compared with PID controller for benchmarking purpose

Real-Time Optimal Control Technique of A Rotary Inverted Pendulum System

This paper presents a real time control technique to stabilize inverted pendulum in the vertical upright position. Stabilize the inverted pendulum is a classical control problem that could be related to some problems in industrial applications. Two common problems that always been encountered by inverted pendulum system is unstable behavior and nonlinear. This lead to numerous studies on the control algorithm to balance the inverted pendulum system in the vertical upright position. Generally, inverted pendulum is mounted on DC motor and is equipped with sensor to measure angular displacement. Inverted pendulum has the same analogy with human that try to balance a broomstick using fingertip. Balancing the Inverted Pendulum requires a good control system. Therefore an optimal control technique is proposed to achieve desired design requirement which are less than 5% overshoot and less than 5 seconds settling time. The controller is optimized to achieve the best performance result. Finally the performance of the controller is compared with PID controller as a benchmark

State-Feedback Controller Based on Pole Placement Technique for Inverted Pendulum System

This paper presents a state space control technique for inverted pendulum system using simulation and real experiment via MATLAB/SIMULINK software. The inverted pendulum is difficult system to control in the field of control engineering. It is also one of the most important classical control system problems because of its nonlinear characteristics and unstable system. It has three main problems that always appear in control application which are nonlinear system, unstable and non-minimumbehavior phase system. This project will apply state feedback controller based on pole placement technique which is capable in stabilizing the practical based inverted pendulum at vertical position. Desired design specifications which are 4 seconds settling time and 5 % overshoot is needed to apply in full state feedback controller based on pole placement technique. First of all, the mathematical model of an inverted pendulum system is derived to obtain the state space representation of the system. Then, the design phase of the State-Feedback Controller can be conducted after linearization technique is performed to the nonlinear equation with the aid of mathematical aided software such as Mathcad. After that, the design is simulated using MATLAB/Simulink software. The controller design of the inverted pendulum system is verified using simulation and experiment test. Finally the controller design is compared with PID controller for benchmarking purpose

A SIMULATION STUDY OF STATE-FEEDBACK CONTROL METHOD FOR ELECTRO HYDRAULIC SERVO MODEL

Electro hydraulic servo system is used by many industries due to its ability to impart large forces. It also has advantage in term of fast response and robustness. The electro hydraulic system suffered from errors of the transient response which are steady state error, settling time and the ripples. It is crucial to design a controller for the system to ensure the reliability of the system. Aiming at the characteristic of the system, steady state feedback control method is designed to compensate the error. The analysis of the system is done based on the transient response specifically on the actuator part. MATLAB Simulink is used as the simulation software to evaluate the force performance of state feedback controller method. The steady state error, settling time and ripple are observed and recorded for each controller. Three methods is applied, which are full feedback, state feedback with feed forward and integral control are compared with proportional, integral and derivatives (PID) controller. The result of each controller shows the differences performance. Based on the simulation results, the feedforward technique is found to be the best control technique for the electro hydraulic servo system due to the requirement performance such as percent overshoot, settling time, rise time and zero steady state error. This good result will directly benefit industries that use electro hydraulic system as their actuator for production machines