Now showing 1 - 10 of 12
  • Publication
    Application of decaying boundary layer and switching function method thorough error feedback for sliding mode control on spacecraft's attitude
    ( 2017-07-18) ;
    Rossiter J.
    Effective operation of small spacecraft implies processors with low cost, energy efficiency and low computational burdens while retaining accurate output tracking. This paper presents the extension of work in [1] on eliminating the chattering for Sliding Mode Control (SMC) using a decaying boundary layer design which is able to achieve these small spacecraft operation needs. The extension is applied on a spacecraft's attitude control, while orbiting the earth with angular velocity, ω0. In SMC, chattering is a main drawback as it can cause wear and tear to moving mechanical parts. Earlier work on a decaying boundary layer design was capable of reducing the chattering phenomena for a limited time only and hence this paper proposes a novel decaying boundary layer and switching function to improve the earlier version. The proposed technique is shown to reduce chattering permanently and also retain control output accuracy.
  • Publication
    A Device-to-Device (D2D) Communication between Mobile Robots using Wireless Communication Protocol in Dynamic Environments
    ( 2024-03-11)
    Sarhan M.A.H.
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    Hashim M.S.M.
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    ; ; ; ;
    Othman S.M.
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    Kanafiah S.N.A.M.
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    Mobile robots must have the ability to guarantee safety for operation in a dynamic environment and close to other moving objects. There are many research had been conducted to make the robot safer by utilizing sensors and big data technology to make the mobile robot able to navigate autonomously and intelligently. One of the key elements in autonomous robots is communication between robots. In this paper, device-to-device (D2D) technology has been used to develop communication between robots. To establish the algorithm for D2D communications, radio frequency (RF) used as communication protocols that can perform D2D communication in real-time applications. The performance of D2D communication was then be assessed in terms of distance and latency. RF transceiver module has been mounted on the robot with Arduino to allow communication between mobile robot to other mobile robots in order to transfer data from robot's sensors to the other mobile robots. By utilizing the gathered information and data, the robot can assess its surroundings and predict the movement of other robots to avoid collisions between robots. The results show that the RF transceiver module is capable to send and receive data between two robots with latency up to 4.865s. It is envisaged that the proposed module can be very useful for developing D2D communication between robots to operate in dynamic environments.
  • 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.
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  • Publication
    Design and Simulation of a Customize Three-axis Gimbal Structure using Finite Element Analysis Method
    ( 2023-03-01)
    Kamaruzzaman M.A.
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    This paper presents a Finite Element Analysis (FEA) on a customized three-axis gimbal design application. Examples of applications of the gimbals such as drones, camera stabilizers, and spacecraft. The SolidWorks software checked the gimbal’s FEA characteristics with no existing load or normal conditions. Using the FEA method, a static simulation analysis where the material of this assembly design uses Polylactic Acid (PLA), used mainly by 3D printer machines. The force is given to the gimbal structure and obtains the results of the maximum value of stress in MPa, displacement in mm, and strain. Thus, based on the results obtained from SolidWorks, the structure will not fail. The maximum stress value between parts is 2.31 MPa for the support part and 3.09 MPa for the assembly model when the yield stress value of the PLA material properties is at 70 MPa. The new design structure for the gimbal hardware focuses on academic purposes based on PLA material and is easy to build using a 3D printer. In the summary, the customized three-axis gimbal design using SolidWorks will not fracture when the design is in normal condition which has a total force of 6.87 N, which is equal to 0.70 kg at 3.09 MPa where the weight of the base, O-ring, and servo motors at the U-shape part. In addition, the design can hold up to 230.87 N, which is equal to 23.54 kg at 69.90 MPa of the stress value before it will fail at 70 MPa.
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  • Publication
    Robot Face and Its Integration to the Mobile Robot for Wireless Signal Collection in the Fingerprinting-Based Indoor Positioning System
    The wireless data collection for instance the Received Signal Strength (RSS) of the Wireless Fidelity (Wi-Fi) remained unfavourable in the Indoor Positioning System utilizing the signal fingerprinting approach. This is because the enormous sampling time and routines works making it tedious human labour. To alleviate this issue, we propose to use a robot for wireless data collection. The robot, named 'ICSiBOT' is a service robot with multiple purpose such as assisting human in daily lives, guest or hospitality robot and man others. This paper mainly describes the ICSiBOT robot face with speech recognition technology and the integration of the robot face to the motion controller. The experimental was conducted to see the correlation between the synthesized instructions from the speech in terms of distance need to be travelled i.e., the location for wireless signal collection and translate them into actual distance travelled. The results showed that the robot is able to travel to the specific distance as instructed to the robot face.
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  • Publication
    Design and Simulation of a Customize Three-axis Gimbal Structure using Finite Element Analysis Method
    ( 2023-03-01)
    Kamaruzzaman M.A.
    ;
    ;
    This paper presents a Finite Element Analysis (FEA) on a customized three-axis gimbal design application. Examples of applications of the gimbals such as drones, camera stabilizers, and spacecraft. The SolidWorks software checked the gimbal’s FEA characteristics with no existing load or normal conditions. Using the FEA method, a static simulation analysis where the material of this assembly design uses Polylactic Acid (PLA), used mainly by 3D printer machines. The force is given to the gimbal structure and obtains the results of the maximum value of stress in MPa, displacement in mm, and strain. Thus, based on the results obtained from SolidWorks, the structure will not fail. The maximum stress value between parts is 2.31 MPa for the support part and 3.09 MPa for the assembly model when the yield stress value of the PLA material properties is at 70 MPa. The new design structure for the gimbal hardware focuses on academic purposes based on PLA material and is easy to build using a 3D printer. In the summary, the customized three-axis gimbal design using SolidWorks will not fracture when the design is in normal condition which has a total force of 6.87 N, which is equal to 0.70 kg at 3.09 MPa where the weight of the base, O-ring, and servo motors at the U-shape part. In addition, the design can hold up to 230.87 N, which is equal to 23.54 kg at 69.90 MPa of the stress value before it will fail at 70 MPa.
      1
  • Publication
    Algorithm development for Vehicle-To-Vehicle (V2V) communication
    This paper presents the development of an algorithm for Vehicle-to-Vehicle (V2V) communication, a crucial technology in Intelligent Transportation Systems (ITS) that holds significant potential for enhancing road safety and traffic efficiency. One of the most common types of vehicle collisions occurs at intersections, particularly those without traffic lights. This study focuses on creating a V2V algorithm designed to prevent collisions in such scenarios. The findings were presented through visual simulations that depict various scenarios involving vehicles approaching an intersection. The algorithm follows a two-step process: Firstly, it utilizes Dedicated Short-Range Communication Systems (DSRCS) to accurately estimate the distance between vehicles. Leveraging this distance information, the algorithm dynamically adjusts the speed of each vehicle. The algorithm's performance is assessed using Convolutional Neural Networks (CNN), which enables a comprehensive evaluation of its reliability and efficiency in V2V communication. The algorithm demonstrates notable enhancements in the reliability and efficiency of V2V communication. This paper serves as a validation of the feasibility of developing more advanced V2V communication algorithm and potentially making significant contributions to the advancement of ITS.
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  • 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.
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  • 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.
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  • 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.
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