Unmanned Aerial Vehicles (UAV) or drones are expected to fly automatically, especially in performing basic maneuvers. the necessary maneuver is to fly straight and level, where no rotation occurs on the roll, pitch, a...
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ISBN:
(数字)9781728123691
ISBN:
(纸本)9781728123707
Unmanned Aerial Vehicles (UAV) or drones are expected to fly automatically, especially in performing basic maneuvers. the necessary maneuver is to fly straight and level, where no rotation occurs on the roll, pitch, and yaw axes that work on the plane. Also, to free from rotational motion, the aircraft needs to maintain its horizontal speed to prevent the vehicle from losing lift and free-fall. this research uses a Linear Quadratic Regulator (LQR) control method to obtain full-state feedback K gain from the control system. the gain of the full-state feedback is used to controlthe output, which is converted into Pulse Width Modulation to controlthe rotational speed of the brushless motor, and the angle of servo. the result of this research is that system response obtained is optimum withthe desired specification.
Harmonics and switching frequency cause a major problem in power system. A novel harmonic elimination technique and low switching frequency in a three-phase pulse width modulation (PWM) inverter are proposed in this p...
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Harmonics and switching frequency cause a major problem in power system. A novel harmonic elimination technique and low switching frequency in a three-phase pulse width modulation (PWM) inverter are proposed in this paper. this inverter is associated with a LC filter. the technique determines the commutation angles based by solving a set of nonlinear system equations. this commutation angles are determined off-line (Pre-Calculed) and stored in the microcontroller memory in order to speed up the online control of the processes. the pre-calculated switching is modelled to cancel the greater part of low-order harmonics and to keep a single-pole dc voltage across the polarized capacitors. LC filter is designed to cancel the high-order harmonics. this approach allows substantial reduction of the harmonic ratio in the AC main output voltage without increasing the switching-frequency per period. Consequently, the duties of the semiconductor power switches are alleviated. To show the validity of the new harmonic elimination and low switching-frequency, DSP based experimental results are presented. these results are very satisfactory and prove the effectiveness of the new approach.
Recent educational advancements spotlight the integration of Item Response theory (IRT) into computer adaptive testing (CAT) for computer-based testing (CBT). this paper demonstrates the necessity of generating divers...
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ISBN:
(数字)9798331540425
ISBN:
(纸本)9798331540432
Recent educational advancements spotlight the integration of Item Response theory (IRT) into computer adaptive testing (CAT) for computer-based testing (CBT). this paper demonstrates the necessity of generating diverse questions withcontrolled difficulty levels to avoid floor and ceiling effects, emphasizing the automation of question creation and pre-assessment of difficulties. Our study contrasts questions based on selecting fitting versus non-fitting examples, discovering that non-fitting example questions pose greater difficulty. Building on this insight, we propose a method to double the CAT item pool by automatically generating non-fitting example questions from human-crafted fitting example questions. this approach not only enriches the diversity of the item pool but also demonstrates its effectiveness in enhancing the robustness of CAT systems.
One of the major driving forces behind technology development is the establishment of equality among everyone. It is intended that the strategic use of technology complements competencies or diminished capacities, imp...
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ISBN:
(纸本)9781479952007
One of the major driving forces behind technology development is the establishment of equality among everyone. It is intended that the strategic use of technology complements competencies or diminished capacities, improving self confidence and autonomy. Blind and partially sighted people often deal withthis inequality in the performance of tasks or daily activities. the presented work reviews some of the proposed technologies to assist visually impaired people in common activities, specifically navigation and going shopping.
the accuracy of autonomous motion is the main challenge for mobile medical robots, especially running in narrow space conditions to transport the casualties in the hospital. this article mainly centers on the human-ro...
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ISBN:
(数字)9781728164793
ISBN:
(纸本)9781728164809
the accuracy of autonomous motion is the main challenge for mobile medical robots, especially running in narrow space conditions to transport the casualties in the hospital. this article mainly centers on the human-robot transmission of the mobile medical robot for narrow space autonomous motion. In order to enable mobile medical robots to autonomously and smoothly transport hospital casualties through narrow aisles, in this paper, we present a robot skill transfer technology, namely a human-robot skill transfer framework of mobile medical robots for autonomous motion with teaching by demonstration, which is that a smooth optimal path is planned through the human motion, and then the Kinect sensor is used to detect human bone movement to learn its motion trajectory so as to achieve trajectory tracking control. Meanwhile, using the Remote Center of Motion (RCM) constraint to minimize the error between the actual trajectory of the medical robot and the tracking reference path to controlthe motion trajectory accurately, human-computer interactive mobile medical robots can smoothly pass through narrow channels. through research and analysis, it is demonstrated that the mobile medical robot proposed in this paper has great feasibility, which is of great reference value in the field of medical rescue.
the dam related disaster caused thousands of people's lives and billions of property damages in the world and in Malaysia. the loss of life and property damages is mostly happened due to dam failure and the lack o...
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this paper explains modeling and control of temperature dynamics on induction furnace. Induction furnace is used for melting metal to process raw material scrap into steel ferrit rate 0.22 wt% carbons. the dynamics re...
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ISBN:
(纸本)9781467367141
this paper explains modeling and control of temperature dynamics on induction furnace. Induction furnace is used for melting metal to process raw material scrap into steel ferrit rate 0.22 wt% carbons. the dynamics response of the induction furnace temperature affects the resulting product. therefore, the controller of temperature dynamics is required to produce the desired process response. the induction furnace systems consist of electrical and thermal system dynamics. the dynamics of the electrical system represents the induction furnace system in the form of an electric circuit i.e. fed current inverter with a parallel resonant circuit. Meanwhile, the thermal system dynamics represents the thermal energy transfer process, which is developed withthe principle of energy balance, including heat generated energy and heat loss. Induction furnace system dynamics is modelled in an order 2 system, with a time constant coil 1000 times faster than time constant temperature. thus, by ignoring the time constant coil, induction furnace system dynamic model can be transformed into a first order nonlinear system. then, linear system can be obtained by making a replacement variable. Induction furnace temperature control has been implemented by adjusting the PWM to controlthe input power to the induction furnace. PI controller is designed in three cases, namely linear model with linear PI controller, saturated linear model with linear PI controller, and saturated linear model with anti-windup PI controller. Each case is simulated by Simulink. To get the appropriate specifications, the temperature should be controlled at 912 Celsius degree. the best results can be achieved with maximum overshoot is 7% and the rise time is 2.9 seconds.
Navigating mobile robots from remote servers offers numerous benefits in industrial settings, such as centralized decision-making and powerful hardware availability. However, the QoS of outsourced controllers is heavi...
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ISBN:
(数字)9798350361230
ISBN:
(纸本)9798350361247
Navigating mobile robots from remote servers offers numerous benefits in industrial settings, such as centralized decision-making and powerful hardware availability. However, the QoS of outsourced controllers is heavily influenced by the communication infrastructure state. Allowing robot applications to gain insights and controlthese states has the potential to significantly enhance mission performance. Programmable 5G O-RAN standardized near real-time network controllers allow application domain entities to access network-specific metrics and control parameters. We propose a solution where multiple robots are connected via 5G O-RAN to a common robot application framework capable of forwarding network performance metrics and managing network resource usage. this new component allows mobile robot applications to optimize their behavior based on network conditions. the system is evaluated in a simulated environment, where necessary navigation computations can be performed either on the mobile robot's local hardware or on more powerful remote hardware. Results demonstrate enhanced mission performance in the case of network-aware navigation and further improvements when the agent's QoS is prioritized.
Simultaneous localization and mapping (SLAM) is one of the core techniques for robots to move autonomously in unknown environments. Rat-SLAM, inspired by the navigation mechanism of the animal brain, provided nice per...
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ISBN:
(数字)9798331506056
ISBN:
(纸本)9798331506063
Simultaneous localization and mapping (SLAM) is one of the core techniques for robots to move autonomously in unknown environments. Rat-SLAM, inspired by the navigation mechanism of the animal brain, provided nice performance in many environments. However, the experience map constructed by RatSLAM excluded semantic information, which is considered to play an important role in human environmental cognition and spatial navigation. In this paper, we propose a method to construct semantic experience map, combining the state-of-the-art deep neural network and RatSLAM. In our method, YOLOv5 is utilized to extract semantic information from the environmental images. the information of static objects, such as road signs, is selected to be incorporated into the experience map, being more closely to the brain navigation. To avoid the same object being repeatedly marked, we propose a semantic dynamic island mechanism, which only marks the center of the island in the experience map. the proposed method is verified on KITTI datasets, showing that it can successfully realize the construction of semantic experience map. the semantic experience maps are more intuitive and understandable by human, facilitating human-robot interaction, i. e. helping robots to fulfil more complex tasks for human.
In the recent years, mobile cloud computing became a vivid topic. On the one hand, the resources of cell phones are rapidly growing, which allow them to solve more and more computationally demanding tasks. On the othe...
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In the recent years, mobile cloud computing became a vivid topic. On the one hand, the resources of cell phones are rapidly growing, which allow them to solve more and more computationally demanding tasks. On the other hand, cell phones are indeed portable: basically, we can assume that all human beings will be equipped by one. thus, a scenario aiming to organize these devices into a local supercomputer to further improve computational performance is completely realistic. this paper aims to introduce a framework, which is able to control and schedule distributed processing by cell phones and tablets to solve complex tasks, when an Internet connection is not available. the communication protocol is based on Extensible Messaging and Presence Protocol (XMPP) to take advantage of its platform independence. We investigate whether XMPP is suitable for such mobile applications, and show how our general framework can form a basis to solve specific tasks by a distributed cell phone network. We introduce some measures based on the available resources of the individual devices which let the scheduler to assign the subtasks accordingly. For demonstration, we consider medical image analysis problems, where retinal/dermatoscopy images acquired by mobile phones are processed by a local mobile network.
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