| |
| |
|
Science Information |
|
|
|
Controls - The Building Blocks of Automation
As man learns to make machines that no longer rely on animal or human power, he finds that he has to develop some means to manage and control them. Powerful machines let loosed by themselves will create havoc and destruction. Control systems have been developed for machines or processes so as to reduce the chances of failure and to provide the required results. Basically, there are open loop control systems and close loop control systems. Open loop systems are those where the controller action is not related to the final result. This means that there is no feedback to the controller to adjust the control action. A simple example is when you fill up a tank using a garden hose. As long as the tap is opened, the water will flow. The height of the water in the tank will not make the tap close. However, when you see the tank becoming full and decide to close the tap, you are adding the element of feedback to the loop. It then becomes a closed loop. But it is a human controlled closed loop. Closed loop systems use feedback from the final result to adjust the control action accordingly. But how would you like to stand in one position, watch the process going on and operate valves, or switches according to the conditions you want? This is very tiring, isn't it? Moreover, human beings are prone to fatigue, boredom, and misjudgment. Manual control works very well only if the speed of the response is very slow, and the result is not very critical or important. Human controlled systems can become very unreliable. Machines are made to replace humans in most control systems today. The basic feature of any control system consists of 4 elements. These are the measuring element, the controlling element, the set value, and the correcting element. The measuring element provides a means of detection/measurement of the conditions required. This is the "eyes" or "ears" (or other senses) of the system. The controlling element is the place where all the decisions on what actions to take are being made. It can be considered the "brains" of the system. It must make decisions based on certain guidelines or values required. The set values are inputted into the system by humans. The correcting element is where the correction to the process is done. It can be considered like the "hands" or "feet" of the system. It must take certain physical actions to bring the processes back to the set value. Well folks, be in control! BREAK FREE from computer dependence! Why use computers when you can read magazines. Avoid eye strain and fatigue. Many years of working experience in Marine, Facilities, Construction has given the author material for writing e-books and articles related to engineering, and management. Subscribe to facworld ezine More information at Marine Engineer and M & E Engineer
MORE RESOURCES:
Science - Google News |
 |
|
|
RELATED ARTICLES
Earthquakes, Tsunamis, Mudslides: Extreme Events - What Do They Mean? In lieu of recent, tumultuous occurrences, people are more compelled than ever to discover the mystery of these modern-day, earth-changing events.One day, Earth(1) is experiencing the fourth largest earthquake in a century - a 9. Many Sci Fi writers have discussed Earthquake predictions Cal Tech along with the Universities in Japan are on the leading edge of this new technology and it is quickly becoming a reality. Soon we will know months in advance of an expected quake and the precise time maybe known hours or minutes before it actually comes. Hurricane and Typhoons Show Drop in Ozone Levels A recent study, which was conducted by the Florida State University, showed that ozone levels drop as the Hurricanes get bigger. The NASA funded study looked at readings in the upper atmosphere of 12 storms. The Valuable Individual How can we, as individuals, participate in waste management? Because some of us are so overwhelmed with Earth's problems, we feel that our contributions have no real consequence in the end. For others, social barriers can be an issue. UAV Acoustic Apparatus for Insect Swarming Stimulus, part two UAV Acoustic Apparatus for Insect Swarming Stimulus, part two; Using Locust swarms to attack our enemies using directional sound to guide them.These plagues and swarms seem to occur randomly, although we do know the migrations are due to over population in an area. Magnetic Propulsion for GI Joe? Thought of the day. I talked to an old guy who gave me this idea, he wanted to create a magnet propelled anti-gravity and directional control craft. Tunneling Concepts for Advanced Warfare I propose research be done to make unmanned tunneling machines to help in warfare. Today more than ever we see the problems with urban warfare. Stem Cells (The Truth) The much publicized stem cell research debate focusing on moral arguments is off target with the goal of real progress in the direction of human physiological benefits potential. No matter what side of this issue you come down on, practical considerations ultimately trump this emotionally clouded subject. Submarine Propulsion and Internet web sources Let us discuss the patent for the Submarine, which is now in the public domain, not that any foreign governments ever cared since they have been building them for years. Since my Grandfather built the first Ring Gyro at Stanford Research years back, I think it wise to discuss these things in a modern context. Aluminum Oxide to Disrupt Laser Weapons In a defensive move to eliminate communication of an enemy, an offensive system using a chemical laser would be a good idea. In manufacturing we have lasers, which coat materials so they can be combined or heat-treated in the application process. June 2005: Weather Forecasts for Vacationers If Johannes Kepler, the renowned 17th century astronomer and discoverer of the planetary laws of motion, could speak from the heavenlies, he might have a few words of wisdom to share with the National Weather Service. Although Kepler's name is not normally associated with meteorology, he was quite the weather forecaster in his day. Travertine Information Travertine is a compacted form of limestone that forms in rivers and hot springs. Water, especially river water, has a lot of minerals in it. Methods of Improving Boiler Efficiency With the rising cost of fuel prices, industries that use steam boilers for heating or power generation are hard pressed to operate at peak efficiencies.While steam consumption, leakages, and other heat transmission losses can contribute to the overall energy bill, this article focuses on the heart of the steam generator - the boiler. Trash Talk Your Way to a Better World North Americans account for less than 10% of the world's population, yet we produce 50% of the world's garbage and consume more than 33% of it's resources. If everyone consumed like the average North American, we would require three Earths!Authors Dave and Lillian Brummet offer an upbeat, proactive look at waste and resource management with their inspiring new book Trash Talk. Shooting Down a UAV in Flight Shooting Down an Enemy UAV so it cannot give away military movement intelligence.We know that with any new innovation in warfare or any new theme that comes along or borrowed technology from another industry to help in the ongoing struggle and conflict of man is short lived. Philosophical Discussion of Distribution Systems To properly understand marketing one needs to understand the natural march of distribution from a colony of ants to Wal-Mart's Distribution System. Efficient systems must be designed or worked out by nature over thousands if not millions of years of evolution. Where Do Insects Go When It Rains? Have you ever wondered where insects go when it rains? We have all seen a poor unfortunate spider washed down the plughole so we know how vulnerable they are to rushing water. Surely then, isn't rain one of their worst enemies?Sorry, but this is one of these "it depends" things. 747 Onboard Laser Might Cause Mistake and Identity Remember when the Russians shot down a Korean Airlines 747 accidentally, which was 4 degrees off it's course and flew over Russian Airspace. Migs shot it down with two missiles, one hitting the tail and one hitting the left wing, everyone on board died. What is Dowsing? Dowsing is definitely an intuitive art and one of the oldest forms of divination in the world. Perhaps the oldest and most familiar image we have a dowser is what is called a field or map dowser. Electromagnetic Energy in Space Tesla was always looking for a way to harvest electromagnetic energy and deliver it to the world wireless, after reading a biography about Tesla, I had come up with this concept.Why not put a satellite that counter rotates the Earth and is located at the poles.
|
| home | site map |
| © 2007 |
