No. 5 (2022)

Article

• Application of a PID controller algorithm tostabilize the altitude of the quadrotor-type UAV

  LÊ HỮU TOÀN, LÊ HOÀNG ANH, TRẦN ĐỨC THUẬN (Author)

  Abstract | PDF (Vietnamese) | Views: 14 Downloads: 6

  This paper proposes a PID controller for a Quadrotor-type UAV in a stable and 
  vertical plane. The PID controller is used in the system to stabilize the altitude and rotation 
  angle for the UAV. The model is built in the Matlab simulink environment. Simulation 
  results show that the controller is highly adaptive to help the UAV expand its operational 
  capabilities.

• Applications of IoT in improving electronic vocational training equipment

  Hồ Minh Thanh, Nguyễn Chí Ngôn (Author)

  Abstract | PDF (Vietnamese) | Views: 6 Downloads: 7

  The objective of this study is to apply the IoT (Internet of Thing) platform in improving electronic vocational training equipment, demonstrated at Long An College. Traditional basic electronic training kits would be integrated with online result monitoring via IoT devices that connect to the experimental circuits. A web application developed for lecturers to monitor the practical results across different practice kits. Practice kits are distributed and communicate with the application through a cloud server. Experimental results prove that the designed IoT device has correctly collected the results of both DC (Direct current) and AC (Alternating current) signals, the web application has effectively monitored the results of the two sample practical circuits including full-wave rectifier and transistor bias circuits. This system is completely upgradeable for the remaining lessons, ready to be applied to organize the practice or serve distance training.

• Calculation and design of electrical system for ALECOP CNC turning

  Nguyen Thuan Hai Dang, Le Trung Hau, Huynh Chi Linh, Ta Van Ranh, Nguyen Huyen Kong Hau (Author)

  Abstract | PDF (Vietnamese) | Views: 8 Downloads: 10

  CNC machining technology is an inevitable trend of all manufacturing processing industries in the world. In Vietnam, following the trend, manufacturing processing factories have switched to precision machining on CNC machines. However, to reduce costs, most factories import used CNC machines. After a long time of use, these machines are damaged and almost no longer have the control software support from the manufacturer, and it is necessary to have solutions to avoid waste. The idea of designing and installing electrical systems, using MACH3 software to control CNC machines is proposed in this paper. It helps to take advantage of damaged CNC machines without the control system, save investment costs for new machines, and reduce the burden of industrial waste treatment in developing countries.

• Research on the influence of road surface roughness on the vibration of Hyundai County bus

  ĐỖ MINH HUY, NGUYỄN THANH TÙNG, TẠ TUẤN HƯNG (Author)

  Abstract | PDF (Vietnamese) | Views: 10 Downloads: 9

  This paper presents the results of research on the influence of road surface roughness 
  on the vibration of Hyundai County bus. The authors used the method of separating the 
  structure of a multi-body system to build the Hyundai County bus vibration model and 
  used the Newton - Euler equation to establish a system of differential equations describing 
  the dynamics. Mathlab - Simulink software was used to survey the vibration of Hyundai 
  County bus with random road surface agitation according to ISO 8608:2016 [1]. The 
  research results show that, when a full-loaded Hyundai County bus moves at a speed 
  of 30 to 80 km/h on a random Class B road surface according to ISO 8608:2016, the 
  evaluation parameters of automobile vibration such as the smooth movement (longitudinal 
  acceleration, horizontal acceleration, vertical acceleration) and dynamic safety (maximum 
  load factor acting on the wheels, minimum load factor acting on the wheels) all meet the 
  requirements of TCVN 6964 - ISO 2631 [2] and VDI - 2057 standard of Germany [3].

• Monitoring and controlling wastewater pumping stations in Bac Lieu City

  Trần Quốc Khánh, Nguyễn Văn Khanh, Trần Quốc Duy, Nguyễn Chí Ngôn (Author)

  Abstract | PDF (Vietnamese) | Views: 4 Downloads: 6

  Since 2006, Bac Lieu city has operated 3 wastewater pumping stations to cope with local flooding. At present, some features of them have been damaged, degraded, and can only be operated manually. The objective of this study is to integrate functions of water level monitoring, control and monitor the pump status into existing pumping stations based on IoTs (Internet of Things). At each station, a device will be designed to collect and update the water level in real time to a cloud server. Particularly for the main station, an additional function of controlling and monitoring the pump is also developed. User commands and pump status are also synchronized to the server. A web application is designed so that the operator can interact with the system most efficiently. All devices have been successfully designed, installed, and operated. Although there are still some disadvantages, the system has operated stably and continuously for a long time, helping to improve the efficiency of pumping stations.

• Research, design, and manufacture of robots supporting patients for medical examination and treatment in hospitals

  DƯƠNG TẤN ĐẠT, NGUYỄN PHƯỚC DĨ, ĐỖ VĂN CHÌA, NGUYỄN THUẬN NGUYÊN (Author)

  Abstract | PDF (Vietnamese) | Views: 19 Downloads: 10

  This paper presents a communication robot design used in hospitals with the task of communicating, receiving and guiding patients for medical examination and treatment. In addition, the robot is also capable of moving through voice and updating patient data information through the application of QR code scanning technology on health insurance cards. The robot has the ability to save patient data on the system via the web. In this study, the authors used the Neutral Network algorithm, the Gradient Descent algorithm, the ADAM algorithm along with processing functions to train and build the robot. The robot is researched with two communication capabilities: direct interaction on the touch screen and through voice. Information about the way, capturing the sequence number, entering personal information is also displayed through the robot's communication interface.

• Building a program to calculate the traction force of a car using a 4-speed mechanical gearbox

  PHẠM ĐỨC HUY, NGUYỄN THANH TÙNG, PHẠM NGỌC ANH (Author)

  Abstract | PDF (Vietnamese) | Views: 7 Downloads: 9

  The paper presents the results of building a program to calculate the traction force of 
  a car using a gasoline engine and a 4-speed mechanical gearbox. The authors used the 
  App designer of Matlab software to build a program to calculate the traction force of a car. 
  The research results show that the program can accurately calculate and simulate graphs 
  such as graphs of the external characteristics of internal combustion engines, graphs of the 
  power balance of internal combustion engines, graphs of the traction force balance of a 
  car, graphs of the dynamic factors, acceleration graphs, and reverse acceleration graphs. 
  This program also allows re-entering the input data and redrawing the graphs directly 
  on the screen, making it easy to survey and adjust the gear ratios of the gearbox to help 
  calculate the traction force of the car to ensure the most optimal.

• Investigating the effects of wind farms on the transmission grid of South-West Area

  Trần Nam Hưng, Nguyễn Phúc Khải (Author)

  Abstract | PDF (Vietnamese) | Views: 7 Downloads: 9

  In recent years, with the encouragement of the Government, renewable energy sources have been developing robustly and widely in the Southern area. Renewable energy sources have supplied clean energy, but at the same time caused many difficulties in operation such as overload and overvoltage on the grids. This paper investigates the effects of voltage and power loss caused by wind farms in the 220kV transmission grids in the South West Area in the period of 2022 – 2025. The authors build the existing grid of the South West Area with three scenarios of wind energy and continue to develop the transmission grid until 2025 based on the planning of the Energy Institute. All grids have been simulated by the ETAP software. The results show that the existing and planned grids have adapted to the limited constraints of voltage. However, the ratio of integrated wind farms is higher, and the power loss is more elevated.

• Design and fabrication of a solar-powered fruit dryer

  Nguyễn Như Tương An, Nguyễn Minh Khang, Trần Thị Thùy Linh, Phạm Thế Thịnh, Đỗ Vinh Quang (Author)

  Abstract | PDF (Vietnamese) | Views: 5 Downloads: 8

  The paper presents a method for design, fabrication and temperature control of a forced convection air dryer powered by solar energy. Solidworks software is implemented to design the 3D model of the dryer which consists of two parts: solar collector and drying chamber. Finally, the dryer is fabricated and temperature in the drying chamber is monitored and controlled using some popular industrial devices and the PID algorithm. Experimental results with fresh jackfruit show that the model operates stably; temperature in the drying chamber is higher than outdoor temperature at the same time and it follows the set temperature closely. The dried product is free from mold, attains relatively low humidity, and is experienced a shorter drying time compared to the sun-drying method. Thus, the solar-powered fruit dryer with features such as drying temperature monitoring and setting basically meets the requirement of drying some agricultural products whose suitable drying temperature is different.

• Investigation of the influence of camber angle on the tire wear

  LƯ THÁI XƯƠNG, CHÂU TRUNG TÍN, NGUYỄN THÁI VÂN (Author)

  Abstract | PDF (Vietnamese) | Views: 4 Downloads: 6

  Tires are an indispensable component of vehicles that directly affect the safety, 
  smoothness, and stability of steering movements. It is the contact between the road 
  surface and the tire that creates the ability to control the vehicle for the driver. For 
  optimal tire performance, it is necessary to have the correct wheel alignment angles, 
  and the camber angle that has a significant influence on the contact surface of the 
  tire and the road surface. In this study, the influence of camber angle on the contact 
  area and wear of tires is presented. The study is simulated using Ansys software with 
  variable load cases and camber angles. The survey helps to assess the wear position of 
  the tire when the camber angle changes.

• A preliminary numerical study on behavior of suction caisson foundation for offshore wind turbine based on finite element analysis program

  Nguyễn Tấn Hưng, Lê Huỳnh Nhật Đăng, Đỗ Hưng Thời, Dương Chung Nguyện (Author)

  Abstract | PDF (Vietnamese) | Views: 4 Downloads: 6

  Suction caisson foundation for offshore wind turbine is increasingly used and providing remarkable benefits such as low cost, high capacity and simplicity of installation. This paper presented a preliminary numerical study on behavior of suction caisson foundation by using finite element analysis program Plaxis 2D. The suction caisson foundations with different geometries were modelled and analyzed. They were considered in the embedded soil having different properties as friction angle and cohesion. Results showed that geometry of suction caisson foundation affected significantly its behavior. Suction caisson whose larger ratio of skirt length to bucket diameter provided higher tensile and bearing capacity. The numerical results in this study showed that the soil properties did not affect remarkably the behavior of suction caisson. When the soil friction angle increased, the tensile and bearing capacity of suction caisson lightly increased. Nevertheless, the soil cohesion seemed not to affect the behavior of suction caisson. The suction caisson geometry, soil parameters and load values were assumed based on literature and the behavior of the suction caisson was evaluated only in vertical direction.

• Experimental studies on the equipment of peeling carrots

  NGUYỄN VĂN NGHĨA, NGUYỄN THANH TÙNG (Author)

  Abstract | PDF (Vietnamese) | Views: 6 Downloads: 9

  This paper presents the results of research, design and manufacture of carrot peelers for the production line and processing of carrot products. The authors applied the experimental planning method, processed experimental data, solved the regression equation to find the optimal working parameters of the carrot peelers such as the rotational speed of the axis Rulo n (v/p), elastic force of knife spring Fd (N), elastic force of spring Rulo Fr (N) and optimal parameters such as peeling rate a (%), specific electricity cost Ar (Wh/kg). As a result, a carrot peeler with a capacity of 200 kg/h was produced.

• A method of interacting with the AWS cloud service from RStudio

  Nguyễn Văn Tâm (Author)

  Abstract | PDF (Vietnamese) | Views: 6 Downloads: 9

  Machine learning and deep learning are the current research areas of great interest to many scientists. However, we must admit that the reality is that there will never be enough CPU or RAM resources for our analysis. The use of cloud computing is a very reasonable choice in the present time. However, manipulating the cloud and running your models is not really easy for novices, so it will be convenient if you can launch and interact with the cloud service right on Rstudio. With this in mind, a method of interacting with the cloud from Rstudio is recommended. In this article, I focus on taking a hands-on approach creating a unique way to practice deep learning of artificial neural networks in the AWS cloud. The results of this study open up an approach to deep learning programming with AWS, providing an additional choice for those looking to enter the field.

• Research on the active rear axle of Teslaelectric cars

  CAO HÙNG PHI, NGUYỄN VĂN THANH (Author)

  Abstract | PDF (Vietnamese) | Views: 6 Downloads: 8

  The paper used the method of separating the structure of a multi-body system to build 
  a dynamic model of the active axle of the Tesla electric car; used the Newton-Euler method 
  to establish the system of equations for the active axle dynamics of the Tesla electric car. 
  The author has applied Mathlab-Simulink software to simulate the active axle dynamics 
  of the Tesla electric car. Research results show that, when the Tesla electric car is moving 
  on a straight road and the resistance forces acting on the left and right wheels are equal, 
  the torques on the left and right semi-axes have the same value, and are about ½ of the 
  torque of the main transmission M4T
  ≈M3P
  ≈1/2.M2max
  ≈120 Nm; The angular velocities of 
  the left and right semi-axes have the value Ψ3P
   ≈ Ψ4T
   ≈ 26,5 rad/s.

• Research on the influence of some parameters on the synchronic process on mechanical gearboxes

  NGUYỄN NGỌC TÂM, NGUYỄN THÁI VÂN, NGUYỄN HOÀNG HIỆP, NGUYỄN QUANG MINH (Author)

  Abstract | PDF (Vietnamese) | Views: 6 Downloads: 11

  Today, cars are more and more widely used in real life. One of the indispensable parts of the car that directly affects the quality of use is the gearbox. Gearbox life and quality of use depend a lot on the gear shifting process, so reasons such as vehicles that are difficult to shift gears, inappropriate transmission ratios that make drivers unable to control the speed, easily lead to vehicle damage, property damage and affect traffic safety. Therefore, it is necessary to study the factors affecting the gear shifting process in order to find a solution to improve the control method of the mechanical gearbox in the precise gear shifting process for efficient automobile exploitation. Determining the factors affecting the time of synchronicity during gear shifting greatly affects the smoothness, the phenomenon of shock during gearing, the speed of shifting is faster and increases the efficiency of use. In this study, the calculation results are presented to determine the parameters affecting the synchronic process and build a simulation model of the influence of angular velocity; coefficient of surface friction; cone angle of the friction surface using Autodesk Inventor software. The obtained simulation results show that when increasing the inclination angle of the cones, increasing the coefficient of friction and reducing the difference in angular velocity, the synchronic time increases.

• A solution for remote control via Internet and power saving support for old generation air conditioners

  Nguyễn Hoàng Thám, Lưu Trọng Hiếu, Nguyễn Chí Ngôn (Author)

  Abstract | PDF (Vietnamese) | Views: 9 Downloads: 5

  This paper introduces a solution to equip old generation air conditioners with a single control circuit. The controller uses IoT technology to be able to monitor and remotely control the device via the internet. In addition, the control circuit is also equipped with the important function of automatically moving the operational point of the air conditioner to the upper edge of the thermal comfort zone according to ASHRAE standards to save electricity, regardless of where the user sets the temperature. The mechanism of moving the operational point of the air conditioner is made possible by resetting the air conditioner temperature by infrared waves and controlling the nebulizer to compensate for the humidity of the air in the room. Experimental results under many scenarios show that the proposed solution is completely feasible.

• Simulation and verification of temperature distribution for fillet weld by GMAW process for mechanical chassis structures of the stair-climbing electric wheelchairs

  TRẦN KHA MINH, LÊ HỒNG KỲ (Author)

  Abstract | PDF (Vietnamese) | Views: 8 Downloads: 4

  Currently, the majority of wheelchairs used by people with disabilities often have simple structures and functions, mainly using human power to operate, or do not have the function of climbing stairs. The load-bearing frame is the part that helps support the entire wheelchair. It also plays the role of linking machines and equipment together into a unified subject so that the wheelchair can operate flexibly. To design the chassis system, steel plates are often used to weld together. However, this work is usually done entirely by hand, which does not guarantee the high requirements of designing and manufacturing the stair climbing electric wheelchairs. In practice, measuring and controlling the temperature of the welding process when welding the chassis of the stair-climbing electric wheelchairs is quite difficult or will require the use of modern and very expensive equipment. In this study, the thermal model of the gas-shielded metal arc welding process (GMAW) of the fillet weld is set up and simulated on ANSYS software. The simulation process based on the calculated heat source gives the temperature distribution in the fillet weld with different modes. Five temperature sensors are mounted on the workpiece to record the temperature during the welding process. Comparison of measured and simulated temperature results shows that they have a good fit for all welding modes. This proves that the construction of the research model, the value of the heat source and the establishment of the initial and boundary conditions in the simulation are relatively close to the actual conditions in the experimental welding process. From there, the welding deformation simulation results will be applied to the optimal chassis design, limiting possible thermal distortions.