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Permanent magnet linear motors (PMLM) are widely used in high precision machineries. With the removal of the transmission elements, the positioning performances of PMLM are easily affected by parameter variations and external disturbances. Various control approaches were proposed, yet it was noticed that majority of these controllers have complex design procedures, and require accurate model parameters of the PMLM, including the nonlinearities of the system. Therefore, in this paper, a Continuous Motion-Nominal Characteristic Trajectory Following (CM-NCTF) controller is proposed as a practical controller for tracking control of an ironless permanent magnet linear motor (IPMLM). The design procedure of CM-NCTF controller is straightforward, and does not require one to go through the hassle of determining the plant model parameters. The proposed controller is made up of two major parts: A Nominal Characteristic Trajectory (NCT) and a proportional-integral (PI) compensator. The NCT is constructed based on the actual response of the system, where the characteristics of the system are measured. The PI compensator works to reduce the motion difference between the NCT and system, thus ensuring the system motion follows the constructed trajectory. The tracking performance under mass variation of the proposed controller is examined experimentally and validated theoretically. Comparative evaluation is also done with a proportional-integral-derivative (PID) controller. Results showed that the designed CM-NCTF controller is indeed robust towards mass changes, while possessing a simple design procedure comparable to PID controller, and does not require the exact plant model parameters.

Makalah ini mengupas amalan-amalan leksikografi yang terkandung dalam karya Frank A. Swettenham, Vocabulary of the English and Malay Languages. Tujuannya ialah untuk meninjau status karya ini sebagai sebuah buku kosa kata Inggeris-Melayu ataupun kamus berdwibahasa. Makalah ini bermula dengan meneliti aspek bunyi (vokal, konsonan dan diftong) yang digunakan untuk melambangkan sebutan bahasa Melayu. Swettenham didapati amat menitikberatkan ketepatan penyebutan sehingga simbol-simbol penanda sebutan digunakan sebagai perlambangan bunyi. Dari segi amalan-amalan leksikografi, entri kata buku ini disusun mengikut abjad. Terdapat pelbagai bentuk kata entri misalnya entri kata dasar, terbitan, majmuk dan sebagainya. Pemerian entri-entri didapati dilakukan dengan menggunakan pendekatan padanan, leksikografi, ensiklopedia dan antonimi. Antaranya, pendekatan padanan terjemahan amat menyerlah dalam menghasilkan karya ini. Justeru, hasil analisis mendapati karya ini lebih berupa sebuah buku padanan kosa kata daripada sebuah kamus dwibahasa.

Electromyography (EMG) is widely used in various fields to investigate the muscular activities. Since EMG signals contain a wealth of information about muscle functions, there are many approaches in analyzing the EMG signals. It is important to know the features that can be extracting from the EMG signal. The ideal feature is important for the achievement in EMG analysis. Hence, the objective of this paper is to evaluate the features extraction of time domain from the EMG signal. The experiment was setup according to surface electromyography for noninvasive assessment of muscle (SENIAM). The recorded data was analyzed in time domain to get the features. Based on the analysis, three features have been considered based on statistical features. The features was then been evaluate by getting the percentage error of each feature. The less percentage error determines the ideal feature. The results shows that the extracted features of the EMG signals in time domain can be implement in signal classification. These findings could be integrated to design a signal classification based on the features extraction.

The objective of this paper is to design a controller which is able to control the output angle for an upper limb of a robotic arm, for precision motion and high speed response. The aim is to optimize the best controller for an upper limb robotic arm system for precision motion, in which improper motion will results in injuries/ fatality and loss of production in manufacturing system. In this research, a robotic arm prototype with a 1 degree-of-freedom (DOF) was designed and fabricated, in which the DC geared motor was implemented. Studies are carried out based on previous research to investigate the suitable type of controller. PID controller and fuzzy logic controller are chosen and compared in terms of their performances such as the steady-state error, settling time, rise time and overshoot. The equipment’s used are Micro-Box 2000/2000C, Cytron DC geared motor, motor driver circuit. Micro-Box module acts as the interface between hardware component and MATLAB R2009a. Open-loop simulations are carried out to obtain the transfer function of the motor and substituted into the system for further simulation analysis. Simulation for the uncompensated system is carried out to observe the close-loop system characteristic without the controller. After that, the close-loop point-to-point (PTP) trajectory control for simulations & experiments are carried out for the compensated systems using PID controller based on the Ziegler-Nichols frequency response method. Analyses are made based on the results obtained and the best type of controller is chosen for achieving precise motion control for the upper limb robotic arm. In this paper, the PID controller shows better performances compared to the Fuzzy Logic controller (FLC) with the steady state error of less than 0.010 and settling time of 0.5s; for the input reference of 150 respectively.

This study is an attempt to describe the terminology of Metroxylon sago among the Melanau community in Mukah, Sarawak (Malaysia). The paper is divided into three main sections: the research method, introduction to the Melanau and their language, and the description of sago terms. The research results reported here are based on data collected in a qualitative research project, featuring face to face interviews in situ. Lexical items related to the sago palm plant and its taxonomy; the harvesting process; processing sago and its products; and, ethno-cultural issues are discussed in this paper. DOI: 10.5901/mjss.2015.v6n6s2p136

A practical control scheme is proposed for a one mass rotary system. It was written to demonstrate the controller performance towards positioning and tracking control. For this system, the Nominal Characteristic Trajectory Following (NCTF) controller is proposed and improved. The objective of NCTF controller is to make the object motion to follow the NCT and ends at it origin. Generally, the NCTF controller consists of a Nominal Characteristic Trajectory (NCT) obtained from open loop response and Proportional Integral (PI) compensator. The CM-NCTF controller is proposed for evaluating the motion performance and compare with the conventional NCTF controller. For positioning control, both NCTF controllers demonstrate almost identical positioning performance. However, for tracking control, CM-NCTF controller demonstrates better tracking performance than the conventional NCTF controller with the smallest motion error presented. Besides, the robustness of the CM-NCTF controller to the variation load is examined.

This paper describes the practical control of non-friction mechanism for precision positioning. Non-friction mechanism is often used for precision positioning. Even though it has a simple structure, still, plant identification is compulsory needed during designing a conventional controller. This makes the controller non- user-friendly and non-practical-used in industry. For overcoming this problem, practical controller based on NCTF (Nominal Characteristic Trajectory Following) controller is proposed. NCTF controller consists of a nominal characteristic trajectory (NCT) and a PI compensator, which is free from exact modeling and parameter identification. The NCT is determined using an open-loop time responses of the mechanism. PI compensator is used to make the mechanism motion to follow the NCT and it is tuned without identification of model parameter. Non-friction mechanism has non-damping characteristic and often has short-working range. A suitable current input to stop the non-damping mechanism within a short working range in open-loop condition and to be able to improve the damping characteristic of the mechanism is necessary. The positioning performances of two different current inputs are examined and discussed. The positioning performance of NCTF control system is evaluated based on simulation and experimental results.

In order to enhance the repair of defects in articular cartilage via cell therapy with autologous chondrocytes, as well as with periosteum-derived progenitor cells (PDPCs), silkworm hemolymph (SH) and a variety of cartilage-specific extracellular matrices (ECMs) including type II collagen, proline, chondroitin 4-sulfate, and chondroitin 6-sulfate were assessed with regard to their efficacy as media supplements. SH, a known anti-apoptotic agent, was found to enhance cell growth, as was shown by the results of a 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay. According to the results of reverse transcriptase polymerase chain reaction (RT-PCR) analyses, the cartilage-specific ECMs were found to stimulate the expression of hyaline cartilage-specific genes, most notably type II collagen and Sox9, in monolayer cultures of PDPCs.

In this paper, the Continuous Motion (CM) NCTF controller is proposed for a point-to-point (PTP) positioning system of a one mass rotary system. For this system, the CM-NCTF controller is designed based on the conventional structure of NCTF controller and improved. The CM-NCTF controller consists of Nominal Characteristic Trajectory (NCT) and Proportional Integral (PI) compensator. It is designed without knowing exact system modeling and parameter evaluation. The NCT is constructed from open loop responses while the PI compensator is designed based on the constructed-NCT itself. The effectiveness of the CM NCTF controller is evaluated and compared with the PID controller for positioning and tracking motion performances experimentally. The robustness of the CM NCTF controller is validated by varying the mass load. Overall, the CM-NCTF controller demonstrates promising positioning and tracking performances, and low sensitivity towards the change of mass load in comparison with the PID controller.

Periosteum-derived progenitor cells (PDPCs) were isolated by characteristic surface markers. Reproducibility of immunophenotypes of the PDPCs was characterized by flow cytometric analysis using fluorescence-activated cell sorter (FACS). SH2(+), SH3(+), SH4(+), CD9(+), CD90(+) and CD105(+) were important eternal characteristic cell surface markers for the PDPCs. The characterized PDPCs maintained their chondrogenic potential in pellet cultures until the 15th passage from primary cell culture.

This paper discusses an experimental setup (mechanical testing) & modeling result of pneumatic muscle actuator. In recent times, the Pneumatic Muscle Actuator (PMA) has achieved popularity in the field of research, robotics and industrial application due to its advantages such as light weight actuator, dynamic, powerful and resistant to dust and clean. Due to its nonlinear dynamics, the muscle actuator is difficult to be controlled. In this paper a pneumatic muscle actuator system is developed for motion control purpose. The dynamic system modeling is discussed. Open loop test and static load experiment have been conducted and validated with the mathematical model. Finally, a brief conclusion of the pneumatic muscle actuator experimental setup and dynamic system modeling is made.

Periosteum-derived progenitor cells (PDPCs) were isolated using a fluorescence-activated cell sorter and their chondrogenic potential in biomaterials was investigated for the treatment of defective articular cartilage as a cell therapy. The chondrogenesis of PDPCs was conducted in a thermoreversible gelation polymer (TGP), which is a block copolymer composed of temperature-responsive polymer blocks such as poly(N-isopropylacrylamide) and of hydrophilic polymer blocks such as polyethylene oxide, and a defined medium that contained transforming growth factor-β3 (TGF-β3). The PDPCs exhibited chondrogenic potential when cultured in TGP. As the PDPCs-TGP is an acceptable biocompatible complex appropriate for injection into humans, this product might be readily applied to minimize invasion in a defected knee.

This paper presents vertical motion control of a one-legged hopping robot using Central Pattern Generator (CPG). The hopping dynamic of the hopping robot is produced by controlling the motor speed to produce force through the crank to the mass, spring, and damper. The classical controllers; PI and PID controller are designed to control the vertical motion of a one legged hopping robot. The parameters for each PI and PID controller are determined by using Ziegler-Nichols method. However, the outputs produced by the controllers do not reach the desired input. Therefore, a CPG model is designed to integrate with these controllers in order to control the hopping robot. The CPG implementation in a mass-spring-damper model is extended to investigate on its dynamic mechanism and vertical motion during hopping. All of integration controller performances are analyzed based on the dynamic response of the hopping robot to reach the desired height. Statistical method is used to analyze the dynamic response. The statistical features that analyzed are mean, mod, error, minimum and maximum boundary of the hopping height produced. As a result, the integration CPG with PI controller is the best controller for the designed one legged hopping robot in term of the mean of the hopping height and error in achieving the desired height.

This paper discusses about the development of output feedback Sliding Mode Control (SMC) and demonstrates that this controller is able to reject disturbance in a nonlinear system. The designed SMC controller works well to ensure system stability and eliminates disturbance in linear and nonlinear dynamics systems. The approach to develop output feedback controller is by implementing High Gain Observer and the output performance from this controller is compared with the output response from the state feedback SMC. Both designed controllers are constructed in simulation by using MATLAB SIMULINK tool. The required gains involve in the designed control laws are tuned heuristically by trial and error approach. The state response results obtained from the simulations are analyzed. Based on the observation and analysis to the results it shows that the output feedback SMC illustrates smooth state response and reduces the effect of disturbance as provided by the state feedback (SMC) without disturbance.

This project develops an algorithm to optimize the dynamic performance of an industrial robot with aid of vision system technology. It consists of three major phases; (1) theoretical, simulation and practical of forward and inverse kinematics for Fanuc LR Mate 200iB robot to determine their D-H parameters, (2) optimization of robot movements, and (3) implementation of practical tasks. The camera is used as a vision sensor to incorporate an intelligent algorithm for the recognition of coordinates of target objects' and to guide the robot to perform certain tasks. The optimization process involves the control of two parameters known as position (Theta) and speed (omega) of the 3 main axes of the robot. Its forward and inverse kinematics problems will be simulated using Robotic tools of Matlab 7.0 and Roboguide V2.3.2. The simulation results will be compared with the real practical movements. This paper will describe the technique, calculation and method on how the first phase was done.