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:

District at or better than state science scores
Coon Rapids Herald, MN - 5 hours ago
The Minnesota Department of Education Tuesday released results from Minnesota’s inaugural online Science MCA-II testing. During the spring of 2008, ...
Area schools vary on science proficiency Litchfield Independent Review
Editorial: More work needed on science learning Minneapolis Star Tribune
Results mixed on MCA science test Farmington Independent
Crookston Daily Times - Winona Post
all 45 news articles


Western Governors University Expands Its Online Degrees in Science ...
MarketWatch - 11 hours ago
The need for highly-qualified science teachers is greater than ever. There are thousands of teacher job openings every year, and school districts struggle ...


Mayor says city still hopeful on Leonardo science center
Salt Lake Tribune, United States - 2 hours ago
... to spend the next several months hashing out a deal that may yet bring a science and culture center to the city's cement fortress at Library Square. ...
The Leonardo: It's time to decide Salt Lake Tribune
all 3 news articles


The Money Times

Oil, Gas Seismic Work Not Affecting Gulf Sperm Whales, Study Shows
Science Daily (press release) - 7 hours ago
... say researchers from Texas A&M University who led the project and released their 323-page report today at the Houston Museum of Natural Science. ...
Study: Seismic has little effect on Gulf whales The Associated Press
Sperm whales live year-round in Gulf, new study finds Houston Chronicle
Study: Oil exploration doesn't harm whales United Press International
PhysOrg.com - KHOU
all 94 news articles


The Associated Press

UPI NewsTrack Health and Science News
United Press International - 6 hours ago
COLUMBUS, Ohio, Aug. 21 (UPI) -- US scientists monitoring Greenland's glaciers say they expect two of the largest glaciers to disintegrate within the next ...
At top of Greenland, new worrisome cracks in ice The Associated Press
Don’t read this if you want The Times
Continued breakup of Greenland's largest glaciers Hindu
io9 - The Tech Herald
all 143 news articles


The Swedish-American Life Science Summit in Stockholm, August 20-22
MarketWatch - 10 hours ago
Against the uncertainties of the life science business and the unpredictable economic climate, the need for collaborative problem solving is greater than ...


New York Times

Search This Blog using Google
ScienceBlogs - 16 hours ago
Not many scientists were convinced the FBI had a solid science case against accused anthrax attacker Dr. Bruce Ivins. So the FBI held a telephone conference ...
Did FBI Scientists Identify a Single, Unique Flask? Lew Rockwell
Anthrax suspect's lawyer speaks up for FBI CNN
Local scientist helped solve anthrax puzzle WTOP
Science News - Durham Herald Sun
all 554 news articles


Texas Instruments Foundation inducts 10 teachers into its STEM Academy
MarketWatch - 7 hours ago
"The future competitiveness of our region's workforce depends on the development of critical science, technology, engineering and math skills," said TI ...


FBI Unveils Science Of Anthrax Investigation
Science Daily (press release) - 7 hours ago
Most people did not know that the work in Ray Goehner’s materials characterization department at Sandia National Laboratories was contributing important ...


Dallas Morning News

Middle school teachers learn Infinity Project's science, math secrets
Dallas Morning News, TX - 20 hours ago
"In designing these modules, we said we have to include the science and the math but make it hands-on as well," said Rosemary Aguilar, ...

Science - Google News

home | site map | Xray Photography
© 2006