• Journal of the Korean Society of Safety
• /
• v.15 no.3
• /
• pp.115-123
• /
• 2000

Pneumatic actuators are widely used in a variety of hazardous working environments. Any process that involves pneumatic actuation is also recognized as "eco-friendly". In most cases, applications of pneumatic actuators require only point-to-point control. In recent years, research efforts have been directed toward achieving precise position tracking control. In this study, a tracking position control method is proposed and experimentally evaluated for a linear positioning system. The positioning system is composed of a pneumatic actuator and a 3-port proportional valve. The proposed controller has an inner pressure control loop and an outer position control loop. A PID controller with feedback linearization is used in the pressure control loop to nullify the nonlinearity arising from the compressibility of the air. The position controller is also a PID controller augmented with the friction compensation by a neural network. Experimental results indicate that the proposed controller significantly improves the tracking performance.rformance.

• Journal of Practical Engineering Education
• /
• v.12 no.1
• /
• pp.1-10
• /
• 2020

The pneumatic control circuit is an important basic element that constitutes factory automation in the era of the 4th Industrial Revolution, and the ability to design and fabricate pneumatic control circuit at the university level is one of the most important educational courses. In this study, it introduced collaborative learning by group, and capstone design technique applied to the subject of design and fabricate of pneumatic control circuit. In addition, it intends to contribute to the innovation of practical engineering education by examining the learning achievement of students. It was investigated analytical skill differences by applying cooperative learning to the experimental group and by applying traditional lecture methods to the comparison group. The experimental group that conducted cooperative learning showed higher academic ability than the comparison group that conducted only traditional lectures, and the t-test results of the significant level p<0.05 also confirmed that there were significant differences between the two groups. It was also responded 13 survey questions in four experimental groups and analyzed the results, showing a high satisfaction level of 4.731 on average. Through this study the design and fabrication of the pneumatic control circuit is more effective in improving students' learning achievement when applying the capstone design technique than when operating as a normal subject and expected to use as a basic material for the development of the curriculum of Capstone design in the future.

• 대한공업교육학회지
• /
• v.31 no.1
• /
• pp.211-225
• /
• 2006

Gabion can be used for the purpose of preventing overflow of river and side loss of road. However the manufacturing process of the gabion is manually controlled especially to the joining process at the terminal part of gabion with small diameter wire. In this paper automatic feeding guide system was designed and fabricated to make automation. The fabricated system was tested in the factory level. Pneumatic system was considered as the main idea of the feeding system. 3/2-way and 5/2-way manual control valve, eight double-acting cylinders were used. The system took 46.48 seconds during a cycle. Additional environmental noise and vibration were not detected when the machine operated at the working area. Based on the theoretical simulation and actual test the fabricated system was well controlled. The system was applied to the patent in 2006.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.2
• /
• pp.140-147
• /
• 2008

This paper describes a Neural Network based PD control scheme for motion control of pneumatic servo cylinder. Pneumatic systems have inherent nonlinearities such as compressibility of air and nonlinear frictions present in cylinder. The conventional linear controller is limited in some applications where the affection of nonlinear factor is dominant. A self-excited oscillation method is applied to derive the dynamic design parameters of linear model. Based on the parameters thus identified, a PD feedback compensator is designed first and then a neural network is incorporated. The experiments of a trajectory tracking control using the proposed control scheme are performed and a significant reduction in tracking error is achieved by comparing with those of a PD control.

• 연구논문집
• /
• s.27
• /
• pp.153-166
• /
• 1997

In industry pneumatic control system has become a important means to obtain automation because of its simplicity, fast speed and low cost. However Due to of the compressibility of air and damping friction between moving parts, it is difficult to achieve high speed driving, accurate positioning and stopping without overshoot in one pneumatic control system. This paper describes the dynamic behaviors of pneumatic linear actuator. The results will be very useful in the prediction of actuated dynamics and for the manufacturers to improve the techniques in their redesign and get better performance. Also, the experimental data is very important for the dynamic simulation and theoretical analysis.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.2 s.245
• /
• pp.105-111
• /
• 2006

This paper describes a Neural Network based PID control scheme for pneumatic NC axes. Pneumatic systems have inherent nonlinearities such as compressibility of air and nonlinear frictions present in cylinder. The conventional PID controller is limited in some applications where the affection of nonlinear factor is dominant. A self-excited oscillation method is applied to derive the dynamic design parameters of linear model. The gains of PID controller are determined using a self tuning scheme. The experiments of a trajectory tracking control using the proposed control scheme are performed and a significant reduction in tracking error is achieved by comparing with those of a PID control.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.5
• /
• pp.603-609
• /
• 2004

This paper deals with the issue of Neural Network-based control for a rodless pneumatic cylinder system which is utilized for a pneumatic XY-plotter. In order to identify the system design parameters, the open loop response of a pneumatic rodless cylinder controlled by a pneumatic servovalve is investigated by applying a self-excited oscillation method. Based on the system design parameters, the PD feedback compensator is designed and then Neural Network is incorporated with it. The experiment of a trajectory tracking control using a PD-NN has been performed and proved its excellent performance by comparing with that of a PD feedback compensator.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.1 s.232
• /
• pp.88-95
• /
• 2005

This paper presents a design scheme of model reference adaptive control incorporating a Neural Network for a pneumatic servo system. The parameters of discrete-time model of plant are estimated by using the recursive least square method. Neural Network is utilized in order to compensate the nonlinear nature of plant such as compressibility of air and frictions present in cylinder. The experiment of a trajectory tracking control using the proposed control scheme has been performed and its effectiveness has been proved by comparing with the results of a model reference adaptive control.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.20 no.2
• /
• pp.30-37
• /
• 2012

Pneumatic Active Engine Mount(PAEM) with open-loop control system has been developed to reduce the transmission of the idle-shake vibration induced by engine effectively and economically. A solenoid valve installed between PAEM and vacuum tank is on-off switched by the Pulse Width Modulate(PWM) control signal to decrease the dynamic stiffness of the engine mount. This paper presents the methodology to identify the optimal values of control parameters of a PAEM, i.e, turn-on timing and duty ratio of PWM signal for 6 different idle driving conditions. A scanning algorithm was first applied to the vehicle test to obtain the approximate optimal control parameters minimizing the vibration at front seat rail and at steering wheel. Then the PAEM system identification was fulfilled to find accurate optimal control parameters by using multi-layer neural networks of Levenberg-Marquardt algorithm with vehicle test data.

• Defense and Technology
• /
• no.10 s.152
• /
• pp.64-69
• /
• 1991

유도무기체계를 위한 구동장치는 크게 유도탄 조종용 구동장치와 유도무기 발사대 터렛 구동장치로 나눌수 있다. 유도탄 구동장치는 1회용이지만 높은 출력/무게비가 요구되고, 발사대 구동장치는 대부하라는 점에서 기술적 특성이 구별된다. 유도무기 구동장치로는 유압, 공압, 전기모타 구동장치가 쓰일수 있으나 종래에는 작은 동력이 요구되는 전술용 유도무기의 구동장치를 제외하고는 많은 경우에 출력대 무게 비가 높은 유압구동장치가 사용되어왔다