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This paper presents the review of design variables optimization and control strategies of a Linear Switched Reluctance Actuator (LSRA). The introduction of various type of linear electromagnetic actuators (LEA) are compared and the advantages of LSRA over other LEA are discussed together with the type of actuator configurations and topologies. The SRA provides an overall efficiency similar to induction actuator of the similar rating, subsequently the friction and windage losses are comparable but force density is better. LSRA has the advantage of low cost, simple construction and high reliability compare to the actuator with permanent magnet. However, LSRA also has some obvious defects which will influence the performance of the actuator such as ripples and acoustic noise which are caused by the highly nonlinear characteristics of the actuator. By researching the design variables of the actuator, the influences of those design variables are introduced and the detail comparisons are analyzed in this paper. In addition, this paper also reviews on the control strategies in order to overcome the weaknesses of LSRA. Keyword:Actuator INTRODUCTIONLinear electromagnetic actuators (LEA) is a mechanism that generate linear motion due to the interactions of the magnetic fields and electromagnetic thrust. The major advantage of electromagnetic actuators over the conventional actuators is that it is almost maintenance free which is due to the absence of mechanical part such as gears The typical design of LEA can be characterized as three topologies: (i) Planar Single Sided; (ii) Planar Double Sided; (iii) Tubular. By comparison, the tubular topology of LEA has greater force density compare to planer topology actuator due to lesser flux leakage and tubular topology actuator minimized the stray magnetic field in the direction of travel along the stator and mover part [5]. Hence, the thrust force and

Two types of rotary motion electrostatic actuators were designed and analyzed using Finite Element Method (FEM) analysis. This paper discussed the comparisons and detailed thrust force analysis of the two actuators. Both designs have similar specifications; i.e the number of rotor’s teeth to stator’s teeth ratio, radius and thickness of rotor, and gap between stator and rotor. Two structures were designed & evaluated; (a) Side-Driven Electrostatic Actuator and (b) Bottom-Driven Electrostatic Actuator. The paper focuses on comparing & analyzing the generated electrostatic thrust force for both designs when the electrostatic actuator’s parameters are varied. Ansys Maxwell 3D software is used to design and analyze the generated thrust force of the two rotary motion electrostatic actuators. The FEM analyses have been carried out by (i) varying the actuator size; (ii), varying the actuator thickness and (iii) varying the actuator teeth ratio. The FEM analysis shows that the Bottom-Drive Electrostatic Actuator exhibit greater thrust force, 4931.80μN compared to the Side-Drive Electrostatic Actuator, 240.96μN; when the actuator’s radius is 700μm, thickness is 50μm, gap between the stator and rotor is 2μm and the teeth ratio is 16:12.

This paper addresses a rotary motion type of electromagnetic actuator that compares two types of electromagnetic actuators; i.e the Permanent Magnet Switching Flux (PMSF) and the Switching Reluctance (SR) actuator. The Permanent Magnet Switching Flux (PMSF) actuator is the combination of permanent magnets (PM) and the Switching Reluctance (SR) actuator. The force optimizations are accomplished by manipulating the actuator parameters; i.e. (i) the poles ratio of the stator and rotor; (ii) the actuator’s size; (iii) the number of winding turns; and (iv) the air gap thickness between the stator and rotor through Finite Element Analysis Method (FEM) using the ANSYS Maxwell 3D software. The materials implemented in the actuator’s parameters optimizations are readily available materials, especially in Malaysia. The excitation current used in FEM analysis for both actuators was between 0A and 2A with interval of 0.25A. Based on the FEM analyses, the best result was achieved by the Permanent Magnet Switching Flux (PMSF) actuator. The PMSF actuator produced the largest magnetostatic thrust force (4.36kN) once the size is scaled up to 100% with the input current, 2A respectively. The maximum thrust force generated by the Switching Reluctance (SR) actuator was 168.85μN, which is significantly lower in compared to the results of the PMSF actuator.

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This paper presents the development of fish length measurement system to obtain the fish length effectively without any contact to the fish. The device which are small and portable, consists of a USB camera that will be connected to a computer for image capturing. A range sensor is combined with the USB camera to detect and fix the image capturing distance. A microcontroller will be the control circuit for the range sensor and LED indication light will be used to allocate the device at the right distance from the fish that it measures. Image processing software, Halcon will be used to analyze and calibrate the fish image for length measurement. Mathematical equations or algorithms are introduced in the image processing software to obtain the actual fish length from the image. The actual fish length from the calculation will be illustrated in the image processing software itself. The experimental results confirms the effectiveness of the proposed system.