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This paper presents the identification of the ThermoElectric Cooler (TEC) plant using a hybrid method of Multi-Verse Optimizer with Sine Cosine Algorithm (hMVOSCA) based on continuous-time Hammerstein model. These modifications are mainly for escaping from local minima and for making the balance between exploration and exploitation. In the Hammerstein model identification a continuous-time linear system is used and the hMVOSCA based method is used to tune the coefficients of both the Hammerstein model subsystems (linear and nonlinear) such that the error between the estimated output and the actual output is reduced. The efficiency of the proposed method is evaluated based on the convergence curve, parameter estimation error, bode plot, function plot, and Wilcoxon’s rank test. The experimental findings show that the hMVOSCA can produce a Hammerstein system that generates an estimated output like the actual TEC output. Moreover, the identified outputs also show that the hMVOSCA outperforms other popular metaheuristic algorithms.

Knee joint is an important part of human body. People with poor knee condition generally have limited physical movement, rendering to mental stress and agony. Knee pain can be categorized into three groups, known as acute injury, chronic injury and medical condition. Current technology to support the knee diagnosis and treatment procedures are limited to the use of manual goniometer, x-ray and magnetic resonance imaging (MRI). Alternative devices with continuous measurement capability for knee monitoring are minimum at this time, mainly due to the difficulties to cover the wide angle of the knee flexion. X-ray and MRI technologies are useful to have some insight on the knee problem, but they are not applicable for continuous monitoring. Aside from being expensive for general use of MRI, x-ray on the other hand can cause short-term side effects due to radiation exposure. The aim of this paper is to demonstrate the use of optical sensor integrated with mechanical gear system as a knee monitoring device. A plastic compartment, made by using 3D printer is used to place the sensor and the gear system. The design of the overall device allows direct attachment on a knee brace for easy placement on the knee. Based on current study, the proposed sensor has a range of motion between 0 deg. to 160 deg., 0.08 deg. resolution as well as support continuous monitoring of the knee. The sensor performance has been demonstrated for gait motion, ascending and descending stairs, sit-to-stand movement and maximum knee flexion applications.

This paper presents the identification of the Thermoelectric Cooler (TEC) plant using a novel metaheuristic called hybrid Multi-Verse Optimizer with Sine Cosine Algorithm (hMVOSCA) based continuous-time Hammerstein model. In the identification, a continuous-time linear system is used, which is more suitable for representing any real plant. The hMVOSCA algorithm is used to reduce the gap between estimated and actual output by identifying the coefficients of both the linear and the nonlinear Hammerstein model subsystems. Efficiency of the hMVOSCA algorithm also evaluated based on the convergence curve, bode plot of the linear subsystem, function plot of the nonlinear subsystem, and statistical performance value. The results demonstrate that the proposed hMVOSCA algorithm can produce the Hammerstein model that generates an estimated output like the actual TEC output. Moreover, the identified outputs also show that the hMVOSCA algorithm outperforms the conventional metaheuristic algorithms such as MVO and SCA by balancing exploration and exploitation and low searching capability.

This paper presents the identification of the ThermoElectric Cooler (TEC) plant using a hybrid method of Multi-Verse Optimizer with Sine Cosine Algorithm (hMVOSCA) based on continuous-time Hammerstein model. These modifications are mainly for escaping from local minima and for making the balance between exploration and exploitation. In the Hammerstein model identification a continuoustime linear system is used and the hMVOSCA based method is used to tune the coefficients of both the Hammerstein model subsystems (linear and nonlinear) such that the error between the estimated output and the actual output is reduced. The efficiency of the proposed method is evaluated based on the convergence curve, parameter estimation error, bode plot, function plot, and Wilcoxon’s rank test. The experimental findings show that the hMVOSCA can produce a Hammerstein system that generates an estimated output like the actual TEC output. Moreover, the identified outputs also show that the hMVOSCA outperforms other popular metaheuristic algorithms.

Visibility is a measure of the distance at which an object or light can be clearly recognized. Visibility for a medium depends on the visible light transmission (VLT). This paper describes the development of VLT measurement system to measure the visibility of air. In recent years, there are many types of devices that can measure VLT. But the existing method and technique have their own disadvantages such as gigantic set up, costly, only can be used in small area and fail to function at night. Therefore, this research will focus on how to measure the visibility by using an open path optical method. The experimental setup for VLT measurement in this research consists of a laser pointer as a light source and spectrometer as a detector. The amount of light that passes through a few series of known-VLT thin films is measured and the percentage values of the measured thin film are set as a measurement base. This new proposed technique is believed to cater the problem mentioned above as the experimental setup is simple, small in size and can measure visibility in any light condition.

Development of various health monitoring devices for health monitoring applications such as spine monitoring, respiration rate, heart rate, as well as upper and lower limb motion detections are at increasing rate. The use of optical fiber-based devices provides significant contribution in this area due to their advantages such as immunity to electromagnetic interference, lightweight and possibly small sensor setup. However, the application of intensity-based optical fiber sensor for human joint motion detections resulted in limited detection angle, where most sensor are not able to detect more than 90 deg. angle. To improve this limitation, we propose an optical sensor approach with mechanical-assisted components assembly that translates angular movement to linear movement. The light detection on the photodiode array at different pixels is analyzed to represent the angle movement of the knee. Based on our study, the proposed device can be applied to detect angle between 0−160° with an accuracy of 0.08°. The obtained results make it possible to apply this technique as knee monitoring device.

Knee monitoring is one of the common injuries suffered by people who are active in extreme sports. Traditional ways to identify these problems are based on background study of the patient, physical examination, and sometimes with the use of x-rays and MRIs. The use of x-rays and MRIs for repetitive use is not preferably suggested by physicians due to the high cost and other associated side-effect related to exposure to radiation. Due to these factors, an alternative device based on optical fibre sensor is proposed in this study. The proposed knee monitoring sensor is based on the use on step index type plastic optical fibre and linear array photodiode sensor. Based on the mathematical estimation and initial sensor measurement, this sensor is able to perform full range of motion between 0 to 155 degrees. The accuracy and resolution of this sensor is 1.0 degree and 0.5 degree, respectively. The aim of this study is to determine the current performance of the device before further improvement could be proposed.

Health monitoring devices are highly demanded in order to determine patients’ health condition, to monitor the health recovery progress, and to help the physiotherapist during rehabilitation period of a patient. This paper is focused on knee joint assessment devices and technology implementation. Knee joint angle measurement devices includes many devices such as accelerometer, electro-goniometer, torsiometer, acoustic, visual sensory, and optic fibre. There are several limitations to these technologies which require improvements. Many of the existing techniques and technologies are becoming conventional and there is a need to identify and to explore better methods to enhance the limitations of existing devices. The need of technologies with higher accuracy, reliability, and lower cost have always been a crucial factor. In this paper, a study of conventional and latest technologies are reviewed, and suggested to further explore the implementation of optical fibre based technology for the above-mentioned application. Optical fibre device has faster response, better accuracy, lighter in weight, lower cost, and is not effected by external physical variable such as electromagnetic waves as compared to conventional sensors.

Human joint angle measurement involves various applications, for example monitoring of spine movement in sagittal and frontal planes, upper limb motion such as shoulder, neck and elbow, as well as lower limb motion such as hip, knee, and ankle. As the range of motions of different human joints are not similar, the output estimation of the designed sensor for these applications need to be carried out prior to sensor development. In this paper, the conceptual design of low-cost plastic optical fibre based on single step index fibre is illustrated, the mathematical modelling is explained, and the sensor’s hardware assemble is designed using CATIA software, before the estimated sensor output is presented. These results will be used as a reference values for actual optical fibre sensor design in the near future.

This paper presents the theoretical investigation and experimental validation of an extrinsic optical fiber bending sensor based on intensity modulation with automatic compensation. The proposed optical fiber bending sensor can measure continuous bending movement in flexion, extension, and lateral directions, simultaneously. The theoretical study is significant in choosing the most suitable parameter values for the sensor so that its sensitivity and working range are applicable for spine monitoring application. The fabricated bending sensor also shows a minimum signal fluctuation due to temperature effect.

An extrinsic optical fibre bending sensor based on intensity modulation technique aimed for physiological application is presented. This sensing technique is capable of measuring the bending angle continuously in flexion, extension and lateral movements. The sensor working range is between −22° and 22° with 0.4° accuracy and 0.1° resolution. From the theoretical estimation, the bending sensor automatically compensates for variation in the source intensity and various losses in the input and output fibres. The experimental results obtained in this investigation verified the theoretical finding. Among the advantages of the this optical bending sensor are being noninvasive, suitable for continuous measurement and immune from electromagnetic effects.

Electrical resistance tomography (ERT) reconstructs internal resistance images of the field from electrical measurements on the surface. The objective of this paper is to obtain the tomogram of the liquid-gas regime of ERT system by using multiple excitation sources. A linear back projection algorithm was implemented as a basic algorithm. Then, it was modified to suit the implementation of multiple excitation sources. A liquid-gas regime in the steel pipe was used as a tested medium. The analysis and performance of the image reconstructed which applies multiple excitation sources were compared with the single excitation technique. As a common strategy applied a single excitation source and produce problem especially at the center of the pipe, this paper mainly focuses on image reconstruction of multiple excitation sources. As a conclusion, 50% of the excitation source cannot produce the image as expected. Tomograms that produced by using the single excitation source were much better than the images obtained by using 50% of the excitation source.

PurposeThe purpose of this paper is to provide a comparative review of intensity‐modulated fiber optic sensors with non‐optical sensors for health monitoring applications, from the current research activities in the area.Design/methodology/approachA range of published research work in sensor design for four different health monitoring applications, including, lumbar spine bending, upper and lower limb motion tracking, respiration and heart rate monitoring, are presented and discussed in terms of their respective advantages and limitations.FindingsThis paper provides information on the various types of sensors applied into the health monitoring area. The sensing techniques of the fiber optic sensor for the stated applications are focused and compared in details to highlight their contributions.Originality/valueA comparative review of published work is illustrated in an informative table content, to allow a clear idea of the current sensing approaches for health monitoring applications.

This paper presents the investigation of an extrinsic optical fibre bending sensor for dynamic spine bending measurement in 2D planes. The sensor consists of one input fibre and three output fibres, confined in two modified holders. The spine bending causes the tilting angle between these two fibres to change, thus modulating the light intensity propagating in each output fibre. The output ratio between the output fibres is applied to represent the bending angle as well as to provide signal referencing for the optical fibre sensor. The study shows that the fabricated sensor is capable of measuring the spine movement in flexion, extension and lateral directions continuously.

This paper presents the implementation of an extrinsic optical fibre sensor based on intensity modulation technique aimed for continuous bending assessment of human spine movement. The sensor under investigation is non-invasive and capable of providing a continuous measurement of the bending angle in both flexion and extension directions of the human spine. The bending assessment is determined based on the measurement of the tilt angle loss between an input fibre and dual output fibres. Additionally, a reference fibre is also integrated into the sensor configuration by means of the divided beam system to compensate for any output variation resulting from temperature changes.

peer-reviewed The light attenuation measurement of a plastic optical fibre sensor based on a referenced intensity modulation technique with respect to different input voltage level and room temperature has been investigated. The results show that light attenuation at the sensor output and reference output are dependent on the source (LED) drive current and temperature, but the output ratio is small and tolerable for this application. This is significant for bending monitoring applications using optical fibre sensor based on intensity modulation, providing a more reliable technique based on power and temperature compensation. PUBLISHED peer-reviewed

This paper presents the investigation of sensing range limit for intensity modulated optical fibre bending sensor using single input and dual input fibres. Plastic optical fibre is used to measure the bending angle by measuring the changes of light intensity using tilt angle loss measurement approach. To define the bending range of the sensor configurations under investigation, the fibre was bended at several bending angle for a 30 second period purposely to reduce the effect of light source fluctuation and drift in measurement. It was found that, with the use of dual input source fibres, the bending angle range can be extended at almost twice angle range than the single input fibre but with a lower output resolution.

This paper presents the development of bending sensor using plastic optical fibre. The bending angle is measured with respect to the changes in light intensity at the receiving fibre. To study the relationship between the sensor's output intensity power and the bending angle, three mediums with different refractive index were used at the gap in between of the emitting and receiving fibres. It was found that, a higher refractive index medium could be used to improve the resolution of the sensor but with a reduced sensor working range.

This paper presents the implementation of motor speed control using Proportional Integral Derrivative (PID) controller using Programmable Logic Controller (PLC). Proportional Integral Derrivative (PID) controller is the technique used to actively control the speed of the motor. An AC motor is used in the research together with the PLC, encoder and Proface touch screen. The model of the PLC that has been used in this project is OMRON CJIG-CPU42P where this PLC has a build in loop control that can be made the ladder diagram quite simple using function block in CX-process tools. A complete experimental analysis of the technique in terms of system response is presented. Comparative assessment of the impact of Proportional, Integral and Derivative in the controller on the system performance is presented and discussed.

This paper presents theoretical investigations into the dynamic characterisation of a two dimensional gantry crane system incorporating payload. A dynamic model of the system is developed using Euler-Langrange formulation. Simulation exercises are performed in Matlab with two different control strategies, PD and PD-Fuzzy controllers. To study the effects of payload weight on the response of the gantry crane system, the sway angle movement of the rope and its respective power spectral density are evaluated with different payload weight being placed at the end of the rope. Simulation results are presented in time and frequency domains. The robustness of the classical and fuzzy controllers in minimizing the sway angle is examined in terms of time response specifications and the results are then discussed in details.

This paper presents theoretical investigations into the dynamic characterisation of a two dimensional gantry crane system. A dynamic model of the system is developed using Euler-Langrange formulation. Simulation exercises are performed in Matlab with three different control strategies; LQR, DFS and PD controllers and then the results are compared with uncontrolled system. To study the effects of payload weight on the response of the gantry crane system, the results are evaluated with different payload weight in the algorithm. Results achieved from simulation work are shown in time and frequency domains. Performance of the feedback controllers in minimizing the sway angle is examined in terms of time response specifications and magnitude of sway. Finally, a comparative assessment of different payload weight to the system performance is assessed and discussed.

This paper presents investigations into the development of hybrid control schemes for sway suppression and rotational angle tracking of a rotary crane system. A lab-scaled rotary crane is considered and the dynamic model of the system is derived using the Euler-lagrange formulation. To study the effectiveness of the controllers, initially a classical controller which is collocated proportional-derivative (PD) controller is developed for control of rotary motion. This is then extended to incorporate a non-collocated fuzzy logic controller for control of sway angle of the pendulum. Implementation results of the response of the rotary crane system with the controllers are presented in time and frequency domains. The performances of the control schemes are assessed in terms of level of sway reduction, rotational angle tracking capability and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

This paper presents the implementation of PID controller using Programmable Logic Controller (PLC) in heating tank of mini automation plant. PID controller is implemented by using ladder diagram in PLC OMRON CJIM-CPU12. A temperature control unit CJ1W-TC001 is also used where the temperature control unit is a special I/O unit that receives inputs directly from thermocouple, to perform PID control. Desired temperature or set point (SP) is set by the user using the Human Machine Interface (HMI) and the controller within the PLC will try to maintain the current temperature base on the set point temperature set by the user. Temperature control is very difficult to be implemented by using ordinary control techniques; hence the purpose of this research is to implement PID controller design using programmable logic controller (PLC) in order to control the time to heat up a particular solution to a desired temperature efficiently without scarifying the stability of the system. A complete analysis using different kind of PID parameters is presented in terms of system response. Performance of the controller is examined in terms of settling time, rise time and percent overshoot. Finally, a comparative assessment of the PID controller on the system performance is presented and discussed.

The increased complexity of the dynamics of robots manipulator considering joint elasticity makes conventional model-based control strategies complex and difficult to synthesize. This paper presents investigations into the development of composite Fuzzy Logic Control for trajectory tracking and vibration control of a flexible joint manipulator. To study the effectiveness of the controllers, a PD-type Fuzzy Logic Controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate a non-collocated Fuzzy Logic Controller for vibration reduction of the flexible joint system. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the composite Fuzzy Logic control schemes are examined in terms of input tracking capability, level of vibration reduction and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

This paper presents investigations into the development of hybrid control schemes for sway suppression and rotational angle tracking of a rotary crane system. A lab-scaled rotary crane is considered and the dynamic model of the system is derived using the Euler-lagrange formulation. To study the effectiveness of the controllers, initially a collocated proportional-derivative (PD) controller is developed for control of rotary motion. This is then extended to incorporate a non-collocated PID controller for control of sway angle of the pendulum. Implementation results of the response of the rotary crane system with the controllers are presented in time and frequency domains. The performances of the control schemes are assessed in terms of level of sway reduction, rotational angle tracking capability and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

The increased complexity of the dynamics of robots manipulator considering joint elasticity makes conventional model-based control strategies complex and difficult to synthesize. This paper presents investigations into the development of PD type Fuzzy Logic Control (FLC) with non-collocated Proportional Integral Derivative (PID) for trajectory tracking and vibration control of a flexible joint manipulator. To study the effectiveness of the controllers, a PD type Fuzzy Logic Controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate a non-collocated PID Controller for vibration reduction of the flexible joint system. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the non-collocated PID control schemes are examined in terms of input tracking capability, level of vibration reduction and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

This paper presents investigations of sway feedback control approaches for a rotary crane system with disturbance effect in the dynamic system. Linear Quadratic Regulator (LQR) controller and Proportional-Derivative (PD)-type Fuzzy Logic controller are the techniques used in this investigation to actively control the sway of rotary crane system. A lab-scale rotary crane system is considered and the dynamic model of the system is derived using the Euler-Lagrange formulation. A complete analysis of simulation results for each technique is presented in time domain and frequency domain respectively. Performances of the controller are examined in terms of sway suppression and disturbances cancellation. Finally, a comparative assessment of the impact of each controller on the system performance is presented and discussed.

This paper presents investigations into the implementation of input shaping techniques in hybrid control schemes of a rotary crane system. A lab-scaled rotary crane is considered and the dynamic model of the system is derived using Euler-Lagrange formulation. To study the effectiveness of the controllers, initially a collocated proportional-derivative (PD) control is developed for horizontal angle position control of rotary crane. This is then extended to incorporate input shaping techniques for anti-swaying control of the system. The positive and modified Specified Negative Amplitude (SNA) input shaping with different derivative orders respectively were designed based on the properties of the system. Implementation results of the response of the rotary crane with the controllers are presented in time and frequency domains. The performances of input shaping in hybrid control schemes are examined in terms of level of input tracking capability, swing angle reduction, and time response specifications. Finally a comparative assessment of the control techniques is discussed and presented.

Conventional model-based control strategies are very complex and difficult to synthesize due to high complexity of the dynamics of robots manipulator considering joint elasticity. This paper presents investigations into the development of composite control schemes for trajectory tracking and vibration control of a flexible joint manipulator respectively. To study the effectiveness of the controllers, initially a collocated PD Controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate a non-collocated Fuzzy Logic Controller and filtering technique for vibration reduction of the flexible joint system. The Butterworth low-pass filter is designed based on the properties of the system. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the composite control schemes are examined in terms of input tracking capability, level of vibration reduction and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

This paper presents investigations into the implementation of input shaping schemes for anti-sway control of a gantry crane system. A lab-scale gantry crane is considered in the experimental work. An unshaped bang-bang input voltage is used to determine the characteristic parameters of the system for design and evaluation of the input shaping schemes. The input shaping schemes with different derivatives were designed based on the properties of the system. Implementation results of the response of the gantry crane with the input shaping schemes are presented in time and frequency domains. The performances of the input shaping are examined in terms of level of swing angle reduction, and time response specifications. Finally a comparative assessment of the input shaping schemes with different derivatives is discussed and presented.

This paper presents investigations into the development of collocated PD control for input tracking and vibration suppression of a flexible joint manipulator. To study the effectiveness of the controllers, a collocated PD controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate input shaper control schemes for vibration reduction of the flexible joint system. The positive zero-vibration-derivative-derivative (ZVDD) and new modified specified negative amplitude zero-vibration-derivative-derivative (SNA ZVDD) input shapers are then designed based on the properties of the system for vibration control. The new SNA ZVDD is proposed to improve the robustness capability while increasing the speed of the system response. The responses of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the collocated PD with input shaping control schemes are examined in terms of input tracking capability, level of vibration reduction, time response specifications and robustness to parameters uncertainty. A comparative assessment of the positive ZVDD and modified SNA ZVDD shapers to the hybrid system performance is presented and discussed.

This paper presents investigations into the development of robust input shaping control schemes for anti-swaying control of a rotary crane system. A nonlinear rotary crane system is considered and the dynamic model of the system is derived using the Euler-Lagrange formulation. An unshaped square-pulse torque input is used to determine the characteristic parameters of the system for design and evaluation of the input shaping control techniques. The positive and modified specified negative amplitude (SNA) input shapers with the derivative effects respectively are designed based on the properties of the system. Simulation results of the response of the rotary crane system to the shaped inputs are presented in time and frequency domains. Performances of the control schemes are examined in terms of sway angle reduction and time response specifications. Moreover, the robustness of the feed-forward control schemes is discussed. Finally, a comparative assessment of the proposed control techniques is presented and discussed.

This paper presents investigations into the development of input shaping with Proportional-Derivative (PD)-type Fuzzy Logic Control for trajectory tracking and vibration control of a flexible joint manipulator. To study the effectiveness of the controllers, a PD-type Fuzzy Logic Controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate input shaper control schemes for vibration reduction of the flexible joint system. The positive zero-vibration-derivative-derivative (ZVDD) and new modified specified negative amplitude zero-vibration-derivative-derivative (SNA-ZVDD) input shapers are then designed based on the properties of the system for vibration control. The new SNA-ZVDD is proposed to improve the robustness capability while increasing the speed of the system response. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the PD-type Fuzzy Logic with input shaping control schemes are examined in terms of input tracking capability, level of vibration reduction, robustness and time response specifications. A comparative assessment of the positive ZVDD and modified SNA-ZVDD shapers to the hybrid system performance is presented and discussed.

This paper presents investigations into the development of input shaping with optimal state feedback for trajectory tracking and vibration control of a flexible joint manipulator. A single-link flexible joint manipulator is considered and the dynamic model of the system is derived using the Euler-Lagrange formulation. To study the effectiveness of the controllers, a linear-quadratic regulator (LQR) controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate input shaper control schemes for vibration reduction of the flexible joint system. The positive zero-vibration-derivative-derivative (ZVDD) and new modified specified negative amplitude zero-vibration-derivative-derivative (SNA-ZVDD) input shapers are then designed based on the properties of the system for vibration control. The new SNA-ZVDD is proposed to improve the robustness capability while increasing the speed of the system response. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the LQR with input shaping control schemes are examined in terms of input tracking capability, level of vibration reduction, robustness and time response specifications. A comparative assessment of the positive ZVDD and modified SNA-ZVDD shapers to the hybrid system performance is presented and discussed.

This paper presents investigations into the development of PD-type Fuzzy Logic Control with different polarities input shaping for anti-sway control of a gantry crane system. A nonlinear overhead gantry crane system is considered and the dynamic model of the system is derived using the Euler-Lagrange formulation. To study the effectiveness of the controllers, initially a PD-type Fuzzy Logic Control is developed for cart position control of gantry crane. This is then extended to incorporate input shaper control schemes for anti-sway control of the system. The positive and modified specified negative amplitude (SNA) input shapers with the derivative effects respectively are designed based on the properties of the system. Simulation results of the response of the system with the controllers are presented in time and frequency domains. The performances of the control schemes are examined in terms of level of input tracking capability, swing angle reduction, time response specifications and robustness to parameters uncertainty in comparison to the PD-type Fuzzy Logic control. Finally, a comparative assessment of the amplitude polarities of the input shapers to the system performance is presented and discussed.

This paper presents the performance of an optimal controller applied to the active suspension system of two-axle and bogie-based railway vehicle systems. The curving performances of both vehicles on varying curve radius and creep coefficients are compared. Computer simulation results have shown that the presence of bogies in a railway vehicle with active suspension system improves the lateral acceleration of the vehicle body (i.e. better comfort) but this requires much greater control effort than the two-axle vehicle. Also, in general, the designed controller is able to provide satisfactory performance for various sizes of curve radii and creep coefficients.

This project presents investigations into the development of hybrid input-shaping and PID control schemes for active sway control of a gantry crane system. The application of positive input shaping involves a technique that can reduce the sway by creating a common signal that cancels its own vibration and used as a feed-forward control which is for controlling the sway angle of the pendulum, while the proportional integral derivative (PID) controller is used as a feedback control which is for controlling the crane position. The PID controller was tuned using Ziegler-Nichols method to get the best performance of the system. The hybrid input-shaping and PID control schemes guarantee a fast input tracking capability, precise payload positioning and very minimal sway motion. The modeling of gantry crane is used to simulate the system using MATLAB/SIMULINK software. The results of the response with the controllers are presented in time domains and frequency domains. The performances of control schemes are examined in terms of level of input tracking capability, sway angle reduction and time response specification.

peer-reviewed This paper presents a study on the application of plastic optical fibre for spine bending monitoring based on an intensity modulation. The bending angle is measured as the angle between the emitting and receiving fibres is changed. The measured light attenuation is compared with a theoretical evaluation and the differences between these values are discussed. It was found that the light attenuation for the light intensity agreed well (margin of error < 15%) with the theoretical value for the range between 180o (representing no bend) and 200o and it was significantly increased for the bending angle beyond that value due to the effect of fibre gap increment which resulted in a less reliable experimental estimation. PUBLISHED peer-reviewed

The increased complexity of the dynamics of robots manipulator considering joint elasticity makes conventional model-based control strategies complex and difficult to synthesize. This paper presents investigations into the development of composite collocated proportional-derivative (PD) and Fuzzy Logic Control for trajectory tracking and vibration control of a flexible joint manipulator respectively. To study the effectiveness of the controllers, a collocated PD Controller is developed for tip angular position control of a flexible joint manipulator. This is then extended to incorporate a non-collocated Fuzzy Logic Controller for vibration reduction of the flexible joint system. Simulation results of the response of the flexible joint manipulator with the controllers are presented in time and frequency domains. The performances of the composite control schemes are examined in terms of input tracking capability, level of vibration reduction and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

This paper presents the development of an extrinsic optical fibre sensor for continuous measurement of the human spine bending movement based on intensity modulation technique. Using the investigated sensor configuration, the bending angle was measurable in both flexion and extension direction with a maximum range of motion of 18° and -10°, respectively. From the output drift assessment of the sensor, bending accuracy of up to 0.5° was achievable, thus making it suitable for clinical environment application. A divided-beam referencing technique was also implemented in the sensor configuration to compensate for the input power fluctuation and temperature variation.

peer-reviewed This paper presents the implementation of power fluctuation compensation for an intensity-based optical fibre bending sensor aimed at monitoring human spine bending in a clinical environment. To compensate for the light intensity changes from the sensor light source, a reference signal was provided via the light reflection from an aluminum foil surface fixed at a certain distance from the source fibre end tips. From the results, it was found that the investigated sensor compensation technique was capable of achieving a 2° resolution for a bending angle working range between 0° and 20°. The study also suggested that the output voltage ratio has a 0.55% diversion due to input voltage variation between 2.9 V and 3.4 V and a 0.25% output drift for a 2 h measurement. With the achieved sensor properties, human spine monitoring in a clinical environment can potentially be implemented using this approach with power fluctuation compensation. PUBLISHED peer-reviewed