Search

This paper defines the efficiency similarity of different motor driving devices. Based on the efficiency function characteristics which can be approximately considered a concave, non-negative function through the origin, we present a kind of optimal control method for a felt driven by three different motors in paper machine. It gives the minimum total power consumption. The optimal control method is to keep the same torque rate for each motor driving device. This method is independent of the linearity or nonlinearity of the system and has no need for the system’s state equation or transfer function. Since the shapes of efficiency functions in nature are similar, the conclusion can also be applied to the energy optimization of other general devices.

In order to realize precise control of the vertical inverting feeding of paper, the paper proposes the scheme to analyse the accuracy. Based on the geometric constraint relations of the feeding device, the position constraint equation of the device is established, together with the speed-acceleration formula; and the relationship between the paper inverting deviation angle and its drop height is obtained using the general equation of dynamics of the horizontal projectile motion as vertical inverting accuracy analysis of the device. The results of the study show that the precise control of the vertical inverting feeding of paper can be realized through the control of the angle.

In this paper, Genetic Algorithm (GA) method has been applied in the moisture control system for auto tuning (PID) parameters. Proportional – Integral – Derivatives control scheme is used to provide an efficient and quiet easier in control engineering applications. Most of the PID tuning methods are used as manually which is difficult and time consuming. Genetic Algorithm which leads to improve the efficiency of tuning of process. The proposed algorithm is used to tune the PID parameters and its performance has been compared with Fuzzy logic techniques.Compare to the fuzzy logic technique dynamic performance specfications such as rise time, peak time and peak overshoot optimal values produced by GA. The plant model represented by the transfer function is obtained by the system identification tool box.

Proportional – Integral – Derivatives control scheme is used to provide an efficient and quiet easier in control engineering applications. Most of the Conventional PID tuning methods are used in manually which is difficult and time consuming. Soft Computing Technique is used to overcome this problem by using Fuzzy logic technique. In this research focuses dynamic performance specification is such as rise time, settling time and peak over shoot. This paper proposes to compare conventional and non-conventional techniques and the result of this comparison, The non-conventional technique (Fuzzy logic) has optimal dynamic performance. The plant model is represented by the transfer function, is obtained by the system identification tool box.

Paper tension is the most important control parameter in roll material production that directly impacts the printing quality of the web offset. Based on the closed-loop paper tension control theory, by conducting a research into the simulation of paper tension control system with MATLAB/SIMULINK, presented the closed-loop control diagram about the paper tension control system. Under different control parameter, the value of the overshoot, respond speed and residual of the system varies. As a result, the quantitative research on the simulation of the system offers a valid means in improving the control accuracy.

An effective method of trajectory reconstruction is presented in order to identify aerodynamic parameters. A novel smoother URTSS, which can get more optimal ballistic parameters, is introduced because of the biggish error caused by the uncertain initial conditions. Finally the validity of the method is verified by the experimental data. It also proves that URTSS can improves the accuracy of the identification of aerodynamic parameters.

Return voltage diagnostic method is an effective method of non-destructive diagnosis in transformer insulating state. The current study is that through experiments get polarization spectrum to analysis the transformer insulating state, but not yet carried out the influence of various factors to the experimental results. So, based on the Debye model and specific parameters comes from one equivalent model of the actual transformer, this paper using RVM methods to simulation analysis maximum return voltage and dominant time constant under different factors. Simulation results show that the diagnostic methods that combine maximum return voltage value with dominant time constant can preferably reflect the transformer insulation state.

The size and the number of folds severely affect the performance of the diesel fuel filter. Computational fluid dynamics method was applied to diesel filter internal flow simulation, and flow pressure lost was test to verify the simulation result. CFD result shown that, when the filter paper angle less than 3°, the internal flow resistance of fuel filter grown rapidly. The flow resistance decreased slowly when filter paper angle of greater than 6°. If filter paper angle was less than 3 °, effective filter area of filter decreased sharply, and filtration efficiency was lower than limit. The filter paper dust capacity increased rapidly, when filter paper angle was greater than 4.5 °, which prolonged filter life. In order to ensure the flow resistance, filtration efficiency and service life, the angle of the filter paper should be between 3 ° to 4.5 °.

Control of pulp pH value is the key step in the process of washing zinc oxide. Due to the characteristics of large time delay and strong nonlinear, the control of pulp pH value is very difficult. In this paper, aiming at the above problem and according to the features of washing operation of zinc oxide powder, design a control system of a fuzzy controller, secondary fuzzy controller and PI controller.

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.

In this paper, a solution for temperature control in a tunnel heat-treatment furnace, used in metallurgy, is presented. The mathematical model of the heating technological process associated to the furnace is expressed using a system of ordinary differential equations and it results through analytical modeling. Based on the determined mathematical model, a temperature control structure which uses the Internal Model Control strategy is proposed. In order to obtain the restrictive control performances imposed by the heat-treatment procedure, the proposed temperature control structure contains two controllers which are tuned using an iterative method and which are used alternatively for the temperature control. The simulations of the temperature control system are presented in a comparative manner, highlighting the main differences between the solution proposed in this paper and the cases of using a classical integer-order controller and a fractional-order controller.

This paper presents design concept and implementation of a micro actuating mechanism that uses a single drive to operate many degrees of freedom. The challenge of this research is to reduce the complexity of the multi-dof actuator mechanism in order to optimize its size and weight so that it is small and light enough to be implemented on other robots or automatic systems where mobility is needed. For example, on the development of the automatic tuning system of multi-string music instruments like piano or harp, instead of implementing one actuator to tune each string, this paper proposed an actuator mechanism that uses a single motor to tune several strings at a time. In the proposed actuator mechanism, a new tiny magnetic clutch is designed to control the direction of the rotation. The worm gear trains are selected to hold the position of the rotation with self-locking ability, which helps prevent rotation when the clutch is disengaged. The size and weight of the mechanism are optimized to fit properly on the musical stringed instrument. In this paper, the prototype and analysis of performance of the proposed mechanism is presented.

This paper investigates the nonlinear dynamics and stability of the shallow von Mises truss, which is a prototype for buckling analysis of several planar and spatial truss systems and shallow lattice shell structures, including the geodesic dome, and which has a theoretical and practical interest in many engineering fields. These structural systems are liable to limit point instability and may fail at load levels well below the theoretical limit point load due to complex nonlinear phenomena that reduce the safety and the dynamic integrity of the structure; this often occurs as a consequence of the erosion of the basins of attraction of the safe pre-buckling solutions. So, it is vital to increase the safety of the structure in a dynamic environment. In this paper a method for controlling the global nonlinear dynamics of mechanical systems is applied to the shallow von Mises truss. The method consists of the (optimal) elimination of homoclinic intersection by properly adding superharmonic terms to a given harmonic excitation. By means of the solution of an appropriate optimization problem, it is possible to select the amplitudes and the phases of the added superharmonics in such a way that the manifolds distance is as large as possible. This methodology is here applied to increase the integrity of the basins of attraction of the system and consequently its practical safety.

Bearing fault signal presents obvious nonlinear and non-stationary characteristics, and local mean decomposition (LMD) method can adaptively process nonlinear and non-stationary signal. Quadratic phase coupling is one of the commonest nonlinear phenomena, and three-order cumulant diagonal slice spectrum is suitable for the extraction of the frequency components involved in quadratic phase coupling. In order to effectively detect the fault features of rolling bearing, a fault feature detection method of rolling bearing based on LMD and diagonal slice spectrum was proposed in the paper. Diagonal slice spectrum was applied in the extraction of the frequency components involved in quadratic phase coupling from the simulation signal, and it successfully extracted the quadratic phase coupling frequency components of the , and . The method was finally used in the detection of the bearing inner race fault features, and the results demonstrated that compared with diagonal slice spectrum of the PF component signals, the diagonal slice spectrum of the PF component envelope signals can identify fault characteristics much clearer and brighter. Meanwhile, the effective extraction of the inner race fault features verified the effectiveness and practicability of the method proposed in this paper.

This paper presents a solution for the real power control, generated by a synchronous generator belonging to a small hydroelectric power plant. The proposed control system is based on the simple feedback structure which contains also, a frequency correction loop. The mathematical models of all the elements from the control structure are detailed. Also, starting from these models, the real power controller (of Proportional – Integral – Derivative type) tuning procedure is presented. In the end of the paper, the simulations results of the control system are presented highlighting the obtained control performances. The proposed solution is a general one and it can be adapted with relative minor changes to any hydroelectric power plant.

The low efficiency restricts the development of pulse continuously variable transmission (P-CVT) mainly, so it is an urgent task to reveal the physical essence of P-CVT, find out the main factor of energy loss, optimize the structure and improve the efficiency. In this paper for this problem, the energy model is established, proposing the calculation method of the energy loss in kinematic pair, the energy loss caused by the resistance of lubrication and the energy loss caused by the damping of the materials of transmission machine. And on this basis, the energy loss will be analyzed specifically by taking the Y2 P-CVT for example, pointing out the corresponding measures which can improve the efficiency. Finally, the physical essence of P-CVT is revealed. Therefore, this paper can provide theory for the efficiency analysis and optimal design of P-CVT.

The dynamic characteristics of planetary transmissions have a direct influence over the possibilities of industrial robots regarding the imposed trajectory. Also, the conditions specific to the achievement of the transient regime have a significant influence over the positioning accuracy of the robots. In this paper, a comparative approach is proposed, applied to four types of planetary transmissions, concerning the gyration torque distribution and computation. Based on the computation equations presented in this paper, some optimization strategies concerning the response times of the overall kinematic chains are proposed.

The paper deals with mode separation process in experimental modal analysis. The main role in this process plays a technique known as Enhanced Frequency Response Function (EFRF), which allows separate the different modes of a structure. The results of the separation are responses of isolated systems with one degree of freedom by means of which complex poles can be estimated with greater accuracy. The paper describes the basic principle of EFRF technique and also presents its application in experimental modal analysis.

This paper presents a co-simulation method to design of speed controller for turbojet fuel pump. Expected fuel pump is used for small turbine engine concept with reducer driven by free turbine. The amount of injected fuel into the combustion chamber is based on the speed of the fuel pump which is controlled by the engine control unit. The final flow of fuel into the combustion chamber is restricted by fuel bypass which constricts the return fuel according to pressure in the nozzles. This back fuel bypass has nonlinear and fixed characteristic determined by its structure. The only way how to control the amount of incoming fuel to the engine is the pump speed control. Effect of the bypass represents a variable component in the fuel pump load and from the view of the speed controller it is a disturbance variable. This paper describes the co-simulation model based on the use of MATLAB/Simulink and MSC Adams environment. This simulation uses interconnection of Simulink controller design and simplified model of the fuel pump dynamics in Adams (without hydraulic modelling).

The paper presents methods used to determine the parameters necessary to build a mathematical model of an underwater inspection robot with a crawler drive. The parameters present in the dynamics equation will be determined by means of advanced mechatronic design tools, including: CAD/CAE software and MES modules. The robot dynamics are described by means of type II Lagrange equations for a non-holonomic system. The details of the kinetic and dynamic equation derivation are highly complex and exceed the scope of this paper. In this paper, the authors concentrate on the methods of determining such dynamic equation parameters as: hydrodynamic resistance factor, precise robot volume and weight, frontal cross-sectional surface and mass moments of inertia.

The paper deals with constructive and functional elements of an adjustable coupling with friction disks and adjustable driving planar mechanisms. The paper shows few conceptual and functional principles, introduce a new function for couplings and a new class of centrifugal couplings. It also presents structural elements of an innovative constructive solution of a centrifugal clutch with friction disks and adjustable centrifugal driving.

The counter-rotating wind turbine is a relatively new concept of wind converter that contains two rotors placed on the same side or on both sides of the nacelle with the aim of increasing the wind energy conversion efficiency. As the rotors are rotating at a lower speed than the generator requires, the wind turbine usually contains a speed increaser to harmonize their running regimes. Similar counter-rotating systems are approached for hydro applications but they are still in the research phase.The paper proposes a novel concept of a 2 DOF speed increaser to be used in counter-rotating systems (wind or hydro). The structural and kinematic features of the 1 DOF and 2 DOF transmission running cases are presented in the paper. The differential transmission is further analyzed and the transmission functions and efficiency are established. Finally, conclusions regarding the use of 2 DOF transmissions in the renewable energy systems are formulated.

This paper investigates the possibility to individually balance the specific shaking forces and shaking moment of the slider-crank mechanism. The most common mean of balancing the slider crank mechanism is to use a counter mass. This solution is applied for almost every slider-crank mechanism used in commercial mechanical devices. However the nature of the mechanism does not allow a perfect balancing in such a way. The different nature of motions that govern the piston displacement and crank rotation imply that a counter mass can only statically balance the mechanism. An ideal dynamic balancing cannot be achieved this way. Therefore in this paper the excitations that act on the mechanism are split by the nature of motion that generates them and balanced accordingly. Two motions are defined, respectively the motion of the piston and the motion of the crank. The inertia force associated with the crank motion is balanced by building a dynamically equivalent system around the axis of the crankshaft while the excitation associated with the motion of the piston is balanced with a progressive spring with two rates.

The paper deals with quadrocopter stability in vertical axis. At first, dynamic model of quadrocopter is introduced. In the paper are derived relations for control error in steady state for PD and PID controller. Based on dynamic model the PID controller is designed by optimizing method. Using designed controller the quadrocopter stability in vertical axis was simulated in software Matlab. In the conclusion the results of the simulation are shown.

The most important in the study of the robots is the kinematic and dynamic analyze. Many researchers studied the kinematics or dynamics without simulation and assisted analyze that it is very heavy to understand the behavior and to show some characteristics. The paper shows one assisted method by using the virtual proper LabVIEW instrumentation (VI). For the forward kinematics (FK) and for direct dynamics (DD) was used one recurrent matrix method which was developed with quaternion algebra, that will be possible to use in many different other types of robots, only by initial settings of the type of joints, the movement axis, the home position, the dimension of each robot’s body, the application point in the working space of the manufacturing cells and the internal coordinates in each joint. For the inverse kinematics (IK) we used the Iterative Pseudo Inverse Jacobian Matrix Method (IPIJMM) coupled with the proper Sigmoid Bipolar Hyperbolic Tangent Neural Network with Time Delay and Recurrent Links (SBHTNN-TDRL). The paper describe all steps in one case study to obtain the space curve in different Euller planes by using one arm type robot and the proposedVI-s. The presented method and the LabVIEWVI-s are generally and they can be used in all other robots types and for all other conventional and unconventional space curves.

Planetary speed reducers are used as the actuating module of the revolute joints for the industrial robots as a result of their specific advantages given by high transmission ratios, efficiencies and reliability. However, planetary speed reducers are currently used with variable high speed electric motors, which leads to increased peripheral speeds for the gears and planet carrier, leading in turn to increased noise during operation. Therefore it becomes necessary to manufacture the gears and planet carrier in an upper precision class, leading to significantly increased costs for the entire planetary transmission. Throughout this paper, novel solutions for planetary speed reducers are proposed, characterized by reduced peripheral speeds of the moving elements. For all the structural variants proposed, the summation method (Svamp’s rule) was applied in order to establish mathematical expressions for the transmission ratios. Subsequently, expressions for the peripheral speeds, corresponding to each moving element were derived, and expressed as a function of the number of revolutions of the input shaft. The method described in this paper was applied for each structural variant proposed, the results obtained being compared and analysed, leading to the optimal variant, characterized by a reduced level of noise and vibrations. Based on the mathematical expressions previously derived, a series of graphical representations of peripheral speeds as a function of the number of revolutions for the input shafts were elaborated for each structural variant proposed. At the same time, some recommendations useful for both designers and manufacturers of planetary speed reducers were made, based on the obtained results.

The main purpose of this work is the presentation reverse task of mechanical systems including active elements. This reserve task is known as synthesis of mechanical system. In result of conducted synthesis was received structures and parameters of a discrete model meeting the defined requirements concerning the dynamic features of the system, in particular, the frequency spectrum. The presented approach i.e. a non-classical synthetic method applied in designing mechanical or mechatronical systems, one (as early as at the design and construction stage) may verify future systems. The aim of this paper is also analysis of obtained system to check relationship between basic system and active subsystem reduction vibrations. This active subsystem was consisted from electric elements. In this paper was used a non-classical method of polar graphs and their relationship with algebra of structural numbers. The use of such a method enables the analysis and synthesis of mechanical systems irrespective of the type and number of the elements of such a system. Active elements give better results (in compare with passive elements) in case of reduction of low frequency vibrations. Presented approach simplifies the process of selecting the dynamical parameters of systems in view of their dynamical characteristics. Thanks to the approach, introduced in this paper, can be conducted as early as during the designing of future functions of the system as well as during the construction of the system. Using method and obtained results can be value for designers of mechanical systems with elements reducing vibrations.

In the paper, we experimentally analyze a pneumatic actuator and possibilities of piston positioning. Paper shows mathematical model of pneumatic actuator. Actuator is experimentally tested and therefor experimental stand is assembled for the purposes of positioning of actuator piston. The changing parameters during the experiment are weight of load and pneumatic pressure. The results show how these parameters can have influence on precise positioning of pneumatic actuator. For experiment there is purposely used open loop control system. The aim of the study is not to show control method for positioning but to show influence of mentioned parameters.

The specific objectives of rehabilitation medicine are maintaining and recovering human body functions, as well as preventing dysfunctionalities by means of kinetic and orthotic techniques and a variety of equipment for support and adaptation. The latter are medical systems facilitating the exercise of muscles at constant or variable speeds according to professional recommendations. The paper presents and discusses the control of rehabilitation equipment designed for the passive mobilisation exercises of joints. The novelty of such equipment resides in its actuation by pneumatic muscles, as well as in its control by means of an SPC 200 controller and WinPISA software. The paper presents a number of examples of rehabilitation programmes and the corresponding motion graphs of the rehabilitation equipment sliding block.

The aim of this paper is finite element presentation for vibration response of the intelligent structure (consisting peizoeectric members) and modification of the response. The active element consists of a piezoelectric ceramic actuator stack, a force transducer and mechanical interfaces. An integral plus double-integral force controller is designed to suppress vibration of the truss. In this paper, in order to find the best piezoelectric operator’s location in spatial truss and optimizing the performance of the member by changing the property of the members, an algorithm is presented to achieve desired natural frequency. Therefore, finite element method of spatial truss is extracted. The results are admitted by ANSYS software. At the end, an example to show the application of the relations is given.

This paper presents the dynamic characteristics and the proposed positioning performance of the system to them investigated experimentally. In this research, we developed the positioning system and we evaluated positioning accuracy. The developed system uses a servo motor for motion actuation. In this paper, we focused on studying the dependency of the positioning error – elementary errors – the position of the conducting element for the mechanism of the transformation of the rotation translation movement, representatively the mechanism screw – screwdriver and on emphasizing the practical consequences in the field of design, regulation and exploitation of the correct identification of all the initial errors in the structure of the mechanism, their character and the selection for an ultimate calculus of these which are of a real practical importance.

In the paper, the problem of designing of mechatronic discrete systems for vibration control has been investigated and generalized. As the design method, the synthesis has been used. Main focus of the paper is given to formalization of the mechatronic structures that contains elements with negative values on different stages of the synthesis process. The study is done based on different distributions methods of dynamical characteristics, dimensionless transformation and retransformation algorithm, simultaneously with verification of possible configurations of connections of piezostack actuators with external electric networks. As the result, various classifications of mechatronic discrete systems and general design constrains have been presented and discussed.

In fluid power systems, flow control may be done either with variable displacement pump or using variable orifice. In this paper is considered the second method for flow control. In a hydraulic system, working pressure is frequently variable and therefore the use of the method does not provide constant flow rates in all operating conditions. In order to keep a constant flow, if this is important in a certain case, the flow control must be accomplished using a pressure compensated flow control valve. In this paper are analyzed possible structural diagrams, mathematical model, block diagram and functional diagram for this kind of equipment. The influence of the spring compression is analyzed also. The diagrams proposed in the paper will be used for the study of a hydraulic system designated for applications with strict flow control. It will represent an important research instrument for such cases.

This paper presents a new mechanical design of mobile robot which can travel in the condition of continuous varying environment, such as colon of human body. Especially, the human colon environment contains an intense diameter change. The suggested mechanical design is capable to adapt in wide diameter changing system by generating two basic motions, rotational and linear motion, with a single actuator. Prototypes is fabricated, and tested result is presented in this paper. Also, experimental result is compared with the mathematical model of the mechanism to verify the feasibility of the proposed mechanism.

The paper proposes a model in order to estimate the location of the center of oscillation and mass of railway bogies or vehicles in order to place in the correct position all the equipments inside the coach. The location of this point is very important for the comfort coefficients regarding passenger coaches, as the position of the coach floor must be horizontal at every moment in order to avoid some disturbed motion as the rotation around the horizontal lateral axes. The proposal for the system of axys, the calculus algorithm and the estimation of the correct position of the Diesel engine inside the coach represent the basis of the paper.

In the paper the control problem of the six-legged walking robot is studied. In order to find the relationship between commonly used by insects gaits (trajectory of the foot point) and stable trajectory of mechanical systems, at first we analyse various previous papers and the gaits of the real insects. For control the motion of the tip of the robot leg a nonlinear mechanical oscillator describing stick-slip induced vibrations further referred as central pattern generator (CPG) has been proposed. The advantages of the proposed model has been presented and compared with other previous applied mechanical oscillators. The possibility of control of the tip of the robot leg via changing parameters characterized oscillator working as a CPG has been discussed. Time series of the joints and configurations of the robot leg during walking are presented. The obtained numerical solutions indicate some analogies between the characteristics of the simulated walking robot and animals found in nature. Moreover, some aspects of an energy efficiency analysis (in order to reduce the energy costs) are discussed for the analysed system and the whole hexapod robot. In particular, we discuss the interplay of the proposed gait patterns and the system energy cost.

This paper discusses the implementation of an adaptive fuzzy autopilot for a scale ship model using a Fuzzy Model Reference Learning Controller (FMRLC). Initially, a fuzzy singleton model of the scale ship model is obtained from experimental input and output data gathered from the turning circle manoeuvre. After that, the paper describes how to design a Fuzzy Model Reference Learning Controller (FMRLC) for controlling the directional heading of the scale ship model. At the end, results of the implementation of the adaptive ship autopilot are showed.

This paper presents a danger analysis for a new octahedron-shaped variable-geometry-truss robot structure under collision with a human head. To lower the danger of collision, design modifications featuring a decoupling of the robot’s moved mass with variable passive compliance and damping will be introduced and a possible implementation in the robots drives is shown. The paper closes in presenting the impact force reduction potential of the resulting hydropneumatic actuator.

This paper proposed semi active controller scheme for magnetorheological (MR) damper of a heavy vehicle suspension known as Tire Force Control (TFC). A reported algorithm in the literature to reduce tire force is Groundhook (GRD). Thus, the objective of this paper is to investigate the effectiveness of the proposed TFC algorithm compared to GRD. These algorithms are applied to a quarter heavy vehicle models, where the objective of the proposed controller is to reduce unsprung force (tire force). The simulation model was developed and simulated using MATLAB Simulink software. The use of semi active MR damper using TFC is analytically studied. Ride test was conducted at three different speeds and three bump heights, and the simulation results of TFC and GRD are compared and analysed. The results showed that the proposed controller is able to reduced tire force significantly compared to GRD control strategy.

Based on the characteristics of the back electromotive force (back-EMF), the rotor position information would be detected. Hence, the main theme of this paper is to design a practical approach to detect the zero cross point (ZCP) of back-EMF through virtual neutral voltage for sensorless brushless direct current (BLDC) motor drives. In contrast to conventional methods, the real neutral voltage of motor is not needed. In order to compensate the phase delay of the back-EMF due to low-pass filter (LPF) under different speeds, a voltage-controlled phase shifter, consisted of hysteresis comparator and voltage-controlled resistor (VCR), is proposed in this paper. The detail circuit model is introduced and some experimental results obtained from a sensorless prototype are shown to confirm the practicality of proposed senosorless drive method.

This paper addresses a two-degree-of-freedom control system design for positioning de-vices such as table drive systems based on the predictive functional control (PFC). The aim of the paper is to improve the tracking performance of the previously developed disturbance observer-based predictive functional control (DOB-PFC) system. To this end, we derive a transfer function representation of the PFC controller. On the basis of the representation, we apply the zero phase error tracking controller (ZPETC) as a feedforward preview controller. Experiments using a real table drive system are conducted to compare the proposed control system with DOB-PFC. The experimental results show that the tracking error is greatly reduced compared to DOB-PFC.

Three Phase Inverters being used today are based on Field Orientation Control (FOC) and Sine Wave PWM (SPWM) techniques because 120 degree or 180 degree conduction methods produce high value of THD (Total Harmonic Distortion) in the power system. The Indirect Field Orientation Control (IFOC) method is difficult to implement in real systems due to speed sensor accuracy issue. This paper discusses the problem with IFOC and a PWM based 180 degree conduction mode for the three phase inverter. The modified control method improves THD and this paper also compares the results obtained using modified control method with the conventional 180 degree conduction mode.

This paper proposed semi active controller scheme for magnetorheological (MR) damper of a heavy vehicle suspension known as Ground Semi Active Damping Force Estimator (gSADE), where it was modified from Semi Active Damping Force Estimator (SADE) algorithm. A reported algorithm known as Groundhook (GRD) was developed where its aim to minimize tire road forces and hence reduce road damage. Thus, the objective of this paper is to investigate the effectiveness of the proposed gSADE algorithm compared to GRD and SADE. These algorithms are applied to a quarter heavy vehicle models and the simulation model was developed and simulated using MATLAB Simulink software. Ride test was conducted at three different speeds and three bump heights, and the simulation results of gSADE, SADE and GRD are compared and analysed. The results showed that the proposed controller is able to reduced tire force significantly compared to GRD control strategy.

This paper produces experimental results comparing operational loss of a power transformer under rated and nonlinear load. A 2kVA three phase three legged dry type power transformer is primarily designed for rated loss; however it is operated with a nonlinear load. Three phase rectifier with variable capacitors is the selected current harmonic source and the distortion at current waveform is controlled by the capacitance values. Initially the operation losses under rated load is measured and then followed with measurement with nonlinear load. At the end of this paper, both type of operation losses is compared and differentiated.

The inverted pendulum system is a challenging control problem in the control theory, which continually moves away from a stable state. The paper presents the design of a Proportional-Integral-Derivative (PID) controller for a single-input multi-output (SIMO) inverted pendulum system and using the Bees Algorithm (BA) to obtain optimal gains for PID controllers. The Bees Algorithm optimizes the gains so that the controller can move the cart to a desired position with the minimum amount of the change in the pendulum’s angle from the vertically upright position during the movement. The tuning aim is to minimize the control responses of the cart’s position and the pendulum’s angle in time domain. MATLAB/Simulink simulation has been performed to demonstrate that the effects on the system performance of PID controllers with optimal gains. The obtained results show that the tuning method by using the Bees Algorithm produced PID controllers successfully within the controller design criteria. Following a description of the inverted pendulum system and the Bees Algorithm, the paper gives the obtained simulation results for the system demonstrating the efficiency of the design.

Recently renewable energy sources have gained much attention as a clean energy. But the main problem occurs with the varying nature with the day and season. Aim of this paper is to conserve the energy, of the natural resources. For solar energy resource, the output induced in the photovoltaic (PV) modules depends on solar radiation and temperature of the solar cells. To maximize the efficiency of the system it is necessary to track the path of sun in order to keep the panel perpendicular to the sun. This paper proposes the design and construction of a microcontroller-based solar panel tracking system. The fuzzy controller aims at maximizing the efficiency of PV panel by focusing the sunlight to incident perpendicularly to the panel. The system consists of a PV panel which can be operated with the help of DC motor, four LED sensors placed in different positions and a fuzzy controller which takes the input from sensors and gives output speed to motor. A prototype is fabricated to test the results and compared with the simulation results. The results show the improved performance by using a tracking system

The paper states a problem of providing quality of geometrical characteristics of machined surfaces, which makes it necessary to forecast the occurrence and amount of oscillations appearing in the course of mechanical treatment. Objectives and tasks of the research are formulated. Sources of oscillation onset are defined: these are coordinate connections and nonlinear dependence of cutting force on the cutting velocity. A mathematical model of forecasting steady-state self-oscillations is investigated. The equation of the cutter tip motion is a system of two second-order nonlinear differential equations. The paper shows an algorithm describing a harmonic linearization method which allows for a significant reduction of the calculation time. In order to do that it is necessary to determine the amplitude of oscillations, frequency and a steady component of the first harmonic. Software which allows obtaining data on surface waviness parameters is described. The paper studies an example of the use of the developed model in semi-finished lathe machining of the shaft made from steel 40H which is a part of the BelAZ wheel electric actuator unit. Recommendations on eliminating self-oscillations in the process of shaft cutting and defect correction of the surface waviness are given.

This paper presents a new approach for designing the Power System Stabilizer. As in power system network, low frequency oscillation always occurs for a long period of time that will decrease the power transfer capability. Power System Stabilizer known as PSS is being installed as one of the control devices in a generating unit. The conventional PSS (CPSS) is the most commonly used in power system, which uses lead-lag compensation. The lack in CPSS has drawn an interest of designing the new approach of PSS to outperform the conventional one. Thus, Bees Algorithm (BA) which is known as one of the numerous intelligent optimization methods is proposed in this paper. It is appears to aid the system stability by optimizing the PSS parameters tuning. The PSS with the BA approach is labelled as BA-PSS and being tested on single machine infinite bus system (SMIB) in Matlab/Simulink environment. BA-PSS performance is compared with CPSS as to validate the ability of the proposed method to achieve great performance in power system stability enhancement. Different type of mechanical input is being injected into the system and the result shows that BA-PSS is capable to optimize the parameters tuning of PSS. BA-PSS also improved the unstable or poorly stable modes as the system achieve the stability with lower overshoot and less time settling. The superior response of BA-PSS controller proved the ability of BA approach in which is capable to solve the lack in CPSS with better performance in enhancing the system stability.

Many power tracing techniques have been developed but are limited to the application of transmission service pricing in a deregulated environment. To expand the knowledge of power tracing theory and its application, this paper adopts the power tracing theory into voltage stability improvement. This paper proposes a modified novel line stability factor index with load tracing capability known as LQP_LT for the purpose of finding the appropriate locations in a power system network for any preventive and corrective actions. Unlike the commonly applied real power tracing, this method presents the reactive power tracing utilizing the proportional sharing method (PSM) with all the line reactive losses being taken into consideration in the network study with the system size remain the same. IEEE 5 bus system is used to demonstrate the LQP_LT concept and all the results obtained are compared with modified Fast Voltage Stability Index with load tracing ability (FVSI_LT). The results obtained found to be efficient in determining the reactive power contributed by a certain load bus in a transmission line which ultimately responsible to cause a stressed line and overall voltage instability in a system.

With the increasing complexity of the space mission, the ability of fast reconstruction of manipulator is more and more important. To solve the problem of space manipulator’s fast reconstruction, this paper designs a novel manipulator that contains mechatronics modular joints and a connecting mechanism. Compared to the traditional manipulator, the manipulator in this paper have the advantage of great convenience of assembling and replacement of the modular joint. In this paper, we analyze the relationship between tolerance ability and structural parameters and computed the tolerance ability after optimization of the connecting mechanism; Using the perturbation method, we conducted the simulation of analysis error. Results show that relationship between the end position error and the error of the modular joints is approximate linear, which providing a theory instruction for the design of manipulator.