Now showing 1 - 8 of 8
  • Publication
    Analysis of WiFi Spatio-Temporal Data for Organic Fingerprinting-based Indoor Positioning System
    The mobile robot navigation is the next huge topic after positioning utilizing fingerprinting-based Wireless Positioning System (WPS). Many of recent works does not discuss this topic yet since many open problems in positioning topic are not yet solved, for instance the issues on multi-devices heterogeneity, instability of WiFi signals, granularity problems in grid-based indoor environment and many others. However, we anticipate that both positioning and navigation works must run in parallel so that the succession are guaranteed. This paper describes the analysis of spatio-temporal data of the signal obtained from the WiFi Access Point. Initial results suggest that the difference between transmitter heights have an effect on the spatio-temporal data while the handover of maximum signal strengths is inherent when three WiFi APs are used.
      1
  • Publication
    Does the Height Matter? A Case for Wi-Fi based Wireless Positioning System
    Wireless Positioning System (WPS) is an emerging field rises with the aim to minimize the development and algorithm cost as well as applicable in many applications. The methods are rather straightforward compared to the use of conventional on-board sensing elements that often require fusion of several sensors as well as complex algorithms. Wireless Fidelity (Wi-Fi) is the choice of elements in WPS due to wide availability as well as use of existing infrastructure. One interesting factor to consider in obtaining higher positioning accuracy is to assess the Wi-Fi height level. Many previous studies proposed optimization of the Wi-Fi antenna heights, but our direction is towards experimental works to observe if the antenna heights does matter or is it a totally insignificant parameter. Three different analyses were conducted on the data, which are statistical, two-layer average and quotient calculations. The results are validated for our experiments heights from 0.5 to 2.0 meter.
      1  44
  • Publication
    Effect of loading protocol on the mechanical properties of 316L stainless steel
    Two types of loading protocol, i.e., monotonic loading and cyclic loading, were compared to investigate the effect on the mechanical properties of 316L stainless steel. The specimen used is a dog-bone specimen in accordance with ASTM E8 and ASTM E606 standard. For cyclic loading, the multiple-step method is used to obtain the hysteresis loop of the material. A total of 13 strain amplitude conditions had been carried out, ranging from 0.05%-0.65%. The stress-strain curve shows that the cyclic stress-strain curve is higher than the monotonic stress-strain curve due to the cyclic hardening behaviour in the 316L stainless steel. The cyclic hardening behaviour increases the ultimate tensile stress of the material. However, when the material gains its strength through cyclic hardening, the ductility in the material will decrease.
      1  29
  • Publication
    Analysis of WiFi Spatio-Temporal Data for Organic Fingerprinting-based Indoor Positioning System
    The mobile robot navigation is the next huge topic after positioning utilizing fingerprinting-based Wireless Positioning System (WPS). Many of recent works does not discuss this topic yet since many open problems in positioning topic are not yet solved, for instance the issues on multi-devices heterogeneity, instability of WiFi signals, granularity problems in grid-based indoor environment and many others. However, we anticipate that both positioning and navigation works must run in parallel so that the succession are guaranteed. This paper describes the analysis of spatio-temporal data of the signal obtained from the WiFi Access Point. Initial results suggest that the difference between transmitter heights have an effect on the spatio-temporal data while the handover of maximum signal strengths is inherent when three WiFi APs are used.
      2
  • Publication
    Position Tracking Performance with Fine Tune Ziegler-Nichols PID Controller for Electro-Hydraulic Actuator in Aerospace Vehicle Model
    Electro-Hydraulic Actuator (EHA) system is a third order non-linear system which is highly suffer from system uncertainties such as Coulomb friction, viscous friction and pump leakage coefficient which makes this system more complicated for the designing of the controller. The Proportional-Integral-Derivative (PID) controller has proposed in this paper to control EHA system and main problem in its application is to tune the parameter to its optimum value. Two different methods are used to tune the PID controller which are trial and error and Ziegler-Nichols method. MATLAB Simulink is used to simulate the system. In order to determine the performance of EHA system for the position tracking. 3 different of external disturbance such as 0N, 5000N and 10000N has been injected into the system. Simulation results show that the Ziegler-Nichols fine tuning method provides the better tracking performance when compared to the trial and error method for every specific disturbance setting. The Ziegler Nichols method provides better disturbance rejection as the performances indexes such as percentage overshoot, settling time and steady state error are not affected by the varying of disturbance.
      2  50
  • Publication
    Numerical evaluation of aluminium 6026-T9 fracture toughness
    Fracture is the separation of an object into two or more pieces caused by crack growth under the action of applied stress. There are many different methods for fracture evaluation has been made but still lacks information on properties of Aluminium 6026-T9. Aluminium 6026 is non-toxic since it does not contain Tin (Sn) and features a great corrosion resistance. This study focuses on the mechanical properties and fracture toughness of Aluminium 6026-T9. The material is cut and shaped into dog-bone specimens by referring the ASTM E8 and was eventually undergoing a tensile test to evaluate the mechanical properties. A linear elastic analysis of three different crack characteristics which are single edge crack, double edge crack and center crack were performed in Mode I analysis to evaluate its fracture toughness. The stress intensity factor (SIF) value near the crack tip obtained from the simulation process were then compared with analytical value and had been discussed. The percentage of error found that the numerical and analytical values are closed to each other.
      1  34
  • Publication
    Integrating Vision System to a Pick and Place Cartesian Robot
    Vision aided pick and place cartesian robot is a combination of machine vision system and robotic system. They communicate with each other simultaneously to perform object sorting. In this project, machine vision algorithm for object sorting to solve the problem in failure sorting due to imperfection of images edges and different types of colours is proposed. The image is acquired by a camera and followed by image calibration. Pre-processing of image is performed through these methods, which are HSI colour space transformation, Gaussian filter for image filtering, Otsu's method for image binarization, and Canny edge detection. LabVIEW edge-based geometric matching is selected for template matching. After the vision application analysed the image, electrical signal will send to robotic arm for object sorting if the acquired image is matched with template image. The proposed machine vision algorithm has yielded an accurate template matching score from 800 to 1000 under different disturbances and conditions. This machine vision algorithm provides more customizable parameters for each methods yet improves the accuracy of template matching.
      2  42
  • Publication
    IoT Based Smart Betta Fish Monitoring system with fish fatality prediction.
    This study enlightens the importance of rearing water quality to Betta fish health. A water quality monitoring system was developed based on water quality parameters namely water pH, temperature (°C) and TDS level (ppm). Fuzzy Logic Algorithm was applied to predict the possibility of the fish to get infected by the disease using combination of the water quality parameters value. Graphical User Interface (GUI) was developed to test the efficiency of the fish disease prediction system using fuzzy logic algorithm before the fuzzy rule been embedded to the IOT system. Arduino Uno Wi-Fi R2.0 and Blynk Apps used for enabling the system to update the aquarium water quality to owner in real-time. Hydroponic technology implemented in this project for recirculate rearing water inside the fish tank. Theoretically, the aquaponic system will help regulate the water tank parameters in optimum range and Betta Splendens should be free from all diseases.
      5  38