The Design of Polynomial Eigenstructure Assignment Controller and Its Robust Analysis for Flexible Spacecraft Precise Control System

2011 ◽  
Author(s):  
Feng Wang ◽  
Finn Ankersen ◽  
Antonios Tsourdos ◽  
Brian White ◽  
Adrian Stanley
Keyword(s):  
Control System ◽  
Flexible Spacecraft ◽  
Eigenstructure Assignment ◽  
Robust Analysis ◽  
Precise Control

Maintaining Low Exhaust Emissions With Turbocharged Gas Engines Using a Feedback Air–Fuel Ratio Control System

1987 ◽  
Vol 109 (4) ◽  
pp. 487-490 ◽  
Author(s):  
D. W. Eckard ◽  
J. V. Serve´
Keyword(s):  
Control System ◽  
Temperature Control ◽  
Exhaust Emissions ◽  
Ambient Conditions ◽  
Load Range ◽  
Heating Value ◽  
Gas Engine ◽  
Precise Control ◽  
Natural Gas Engine ◽  
Fuel Ratio

Maintaining low exhaust emissions on a turbocharged, natural gas engine through the speed and load range requires precise control of the air–fuel ratio. Changes in ambient conditions or fuel heating value will cause the air–fuel ratio to change substantially. By combining air–gas pressure with preturbine temperature control, the air–fuel ratio can be maintained regardless of changes in the ambient conditions or the fuel’s heating value. Design conditions and operating results are presented for an air–fuel controller for a turbocharged engine.

Design of Distributed Control System of Liquid Fermentation Based on S7-300 PLC and WinCC

2014 ◽  
Vol 651-653 ◽  
pp. 697-702
Author(s):  
Wei Zhang ◽  
Xuan Li ◽  
Fang Yang ◽  
Jiao Jiao Wang
Keyword(s):  
Control System ◽  
Distributed Control ◽  
Frequency Control ◽  
Distributed Control System ◽  
Precise Control ◽  
Liquid Fermentation ◽  
Computer Based ◽  
Fermentation Parameters ◽  
A Company ◽  
Control Accuracy

In order to improve the automation level for the control system of liquid fermentation of a company in Hubei province, and combine with the requirements of the company, a distributed control system of liquid fermentation is designed. The control system is composed of host computer based on WinCC, and the slave computer is S7-300 PLC of SIEMENS. The fermentation parameters, including rotation speed, temperature, pH, DO, O2, CO2, can be real-time online collected, and realize the frequency control of motor and precise control of temperature. The experiment result shows that the system runs stably and credibly, the parameters can be collected accurately and the temperature control accuracy has been achieved to be ±0.1°C.

Development of Low-Cost Wearable Servo Valve Using Buckled Tube Driven by Servo Motor

2013 ◽  
Vol 393 ◽  
pp. 532-537 ◽  
Author(s):  
Abdul Nasir ◽  
Tetsuya Akagi ◽  
Shujiro Dohta ◽  
Ayumu Ono ◽  
Yusuke Masago
Keyword(s):  
Control System ◽  
Flow Rate ◽  
Position Control ◽  
Low Cost ◽  
Control Valve ◽  
Artificial Muscle ◽  
Pneumatic Actuators ◽  
Servo Valve ◽  
Precise Control ◽  
Care Systems

Recently, power assisted nursing care systems have received much attention and those researches have been done actively. In such a control system, an actuator and a control valve are mounted on the human body. Designing the system, the size and weight of the valve become serious concerns. The purpose of our study is to develop a small-sized, lightweight and low-cost servo valve for precise control using wearable pneumatic actuators. In this study, a low-cost wearable servo valve that can control the output flow rate by changing the twisted angle of the buckled tube in the servo valve is proposed and tested. The position control system of McKibben rubber artificial muscle using tested valve and embedded controller is also proposed and tested. As a result, we confirmed that the tested servo valve can control the flow rate in both supply and exhaust in an analog way. In addition, the estimated cost of the proposed valve can be reduced about 100 times cheaper (10 US Dollar) compared with the typical servo valve.

scholarly journals Flight Control Design for a Tailless Aircraft Using Eigenstructure Assignment

2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Clara Nieto-Wire ◽  
Kenneth Sobel
Keyword(s):  
Control System ◽  
Flight Control ◽  
Eigenstructure Assignment ◽  
Flight Control System ◽  
Nonlinear Simulation ◽  
Thrust Vectoring ◽  
Stability Margins ◽  
Gain Margin ◽  
Command Systems ◽  
Tailless Aircraft

We apply eigenstructure assignment to the design of a flight control system for a wind tunnel model of a tailless aircraft. The aircraft, known as the innovative control effectors (ICEs) aircraft, has unconventional control surfaces plus pitch and yaw thrust vectoring. We linearize the aircraft in straight and level flight at an altitude of 15,000 feet and Mach number 0.4. Then, we separately design flight control systems for the longitudinal and lateral dynamics. We use a control allocation scheme with weights so that the lateral pseudoinputs are yaw and roll moment, and the longitudinal pseudoinput is pitching moment. In contrast to previous eigenstructure assignment designs for the ICE aircraft, we consider the phugoid mode, thrust vectoring, and stability margins. We show how to simultaneously stabilize the phugoid mode, satisfy MIL-F-8785C mode specifications, and satisfy MIL-F-9490D phase and gain margin specifications. We also use a cstar command system that is preferable to earlier pitch-rate command systems. Finally, we present simulation results of the combined longitudinal/lateral flight control system using a full 6DOF nonlinear simulation with approximately 20,000 values for the aerodynamic coefficients. Our simulation includes limiters on actuator deflections, deflection rates, and control system integrators.

Design and Experimental Study of Deposition Temperature Control System in Ultra-High Vacuum

2012 ◽  
Vol 571 ◽  
pp. 564-568
Author(s):  
Zhi Dan Yan ◽  
Li Dong Sun ◽  
Chun Guang Hu ◽  
Xiao Tang Hu ◽  
Peter Zeppenfeld
Keyword(s):  
Control System ◽  
Temperature Control ◽  
Deposition Temperature ◽  
Film Growth ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Temperature Control System ◽  
Growth Morphology ◽  
Precise Control ◽  
Key Factor

Deposition temperature is a key factor influencing the growth morphology of thin-films, aiming at this phenomenon, a precise control system of deposition temperature in ultra-high vacuum is developed in the paper. It can realize accurate temperature control in a range of 150K to 450K during experiment by combination of resistance heating up and liquid helium cooling down strategies, which is benefit to further understand the temperature-depended mechanism of organic molecule thin-film growth. Besides, it is experimentally studied that the growth morphology of p-6p molecules on a mica substrate is closely related to the substrate deposition temperature, indicating that the length of p-6p nano-fibers is proportional to the deposition temperature, while their distribution density is inversely proportional to the temperature.

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