How Robots Work by Tom Harris

Posted on , updated on by Computron

by Tom Harris

On the most basic level, human beings are made up of five major components:

  • A body structure
  • A muscle system to move the body structure
  • A sensory system that receives information about the body and the surrounding environment
  • A power source to activate the muscles and sensors
  • A brain system that processes sensory information and tells the muscles what to do

Of course, we also have some intangible attributes, such as intelligence and morality, but on the sheer physical level, the list above about covers it.

A robot is made up of the very same components. A typical robot has a movable physical structure, a motor of some sort, a sensor system, a power supply and a computer “brain” that controls all of these elements. Essentially, robots are man-made versions of animal life — they are machines that replicate human and animal behavior.

In this article, we’ll explore the basic concept of robotics and find out how robots do what they do.

Joseph Engelberger, a pioneer in industrial robotics, once remarked “I can’t define a robot, but I know one when I see one.” If you consider all the different machines people call robots, you can see that it’s nearly impossible to come up with a comprehensive definition. Everybody has a different idea of what constitutes a robot.

You’ve probably heard of several of these famous robots:

  • R2D2 and C-3PO: The intelligent, speaking robots with loads of personality in the Star Wars movies
  • Sony’s AIBO: A robotic dog that learns through human interaction
  • Honda’s ASIMO: A robot that can walk on two legs like a person
  • Industrial robots: Automated machines that work on assembly lines
  • Data: The almost human android from Star Trek
  • BattleBots: The remote control fighters on Comedy Central
  • Bomb-defusing robots
  • NASA’s Mars rovers
  • HAL: The ship’s computer in Stanley Kubrick’s 2001: A Space Odyssey
  • Robomower: The lawn-mowing robot from Friendly Robotics
  • The Robot in the television series “Lost in Space”
  • MindStorms: LEGO’s popular robotics kit

All of these things are considered robots, at least by some people. The broadest definition around defines a robot as anything that a lot of people recognize as a robot. Most roboticists (people who build robots) use a more precise definition. They specify that robots have a reprogrammable brain (a computer) that moves a body.

By this definition, robots are distinct from other movable machines, such as cars, because of their computer element. Many new cars do have an onboard computer, but it’s only there to make small adjustments. You control most elements in the car directly by way of various mechanical devices. Robots are distinct from ordinary computers in their physical nature — normal computers don’t have a physical body attached to them.

Robot Basics

The vast majority of robots do have several qualities in common. First of all, almost all robots have a movable body. Some only have motorized wheels, and others have dozens of movable segments, typically made of metal or plastic. Like the bones in your body, the individual segments are connected together with joints.
Robots spin wheels and pivot jointed segments with some sort of actuator. Some robots use electric motors and solenoids as actuators; some use a hydraulic system; and some use a pneumatic system (a system driven by compressed gases). Robots may use all these actuator types.

A robot needs a power source to drive these actuators. Most robots either have a battery or they plug into the wall. Hydraulic robots also need a pump to pressurize the hydraulic fluid, and pneumatic robots need an air compressor or compressed air tanks.

The actuators are all wired to an electrical circuit. The circuit powers electrical motors and solenoids directly, and it activates the hydraulic system by manipulating electrical valves. The valves determine the pressurized fluid’s path through the machine. To move a hydraulic leg, for example, the robot’s controller would open the valve leading from the fluid pump to a piston cylinder attached to that leg. The pressurized fluid would extend the piston, swiveling the leg forward. Typically, in order to move their segments in two directions, robots use pistons that can push both ways.

The robot’s computer controls everything attached to the circuit. To move the robot, the computer switches on all the necessary motors and valves. Most robots are reprogrammable — to change the robot’s behavior, you simply write a new program to its computer.

Not all robots have sensory systems, and few have the ability to see, hear, smell or taste. The most common robotic sense is the sense of movement — the robot’s ability to monitor its own motion. A standard design uses slotted wheels attached to the robot’s joints. An LED on one side of the wheel shines a beam of light through the slots to a light sensor on the other side of the wheel. When the robot moves a particular joint, the slotted wheel turns. The slots break the light beam as the wheel spins. The light sensor reads the pattern of the flashing light and transmits the data to the computer. The computer can tell exactly how far the joint has swiveled based on this pattern. This is the same basic system used in computer mice.

These are the basic nuts and bolts of robotics. Roboticists can combine these elements in an infinite number of ways to create robots of unlimited complexity.

The Robotic Arm

The term robot comes from the Czech word robota, generally translated as “forced labor.” This describes the majority of robots fairly well. Most robots in the world are designed for heavy, repetitive manufacturing work. They handle tasks that are difficult, dangerous or boring to human beings.
The most common manufacturing robot is the robotic arm. A typical robotic arm is made up of seven metal segments, joined by six joints. The computer controls the robot by rotating individual step motors connected to each joint (some larger arms use hydraulics or pneumatics). Unlike ordinary motors, step motors move in exact increments (check out Anaheim Automation to find out how). This allows the computer to move the arm very precisely, repeating exactly the same movement over and over again. The robot uses motion sensors to make sure it moves just the right amount.

An industrial robot with six joints closely resembles a human arm — it has the equivalent of a shoulder, an elbow and a wrist. Typically, the shoulder is mounted to a stationary base structure rather than to a movable body. This type of robot has six degrees of freedom, meaning it can pivot in six different ways. A human arm, by comparison, has seven degrees of freedom.

Your arm’s job is to move your hand from place to place. Similarly, the robotic arm’s job is to move an end effector from place to place. You can outfit robotic arms with all sorts of end effectors, which are suited to a particular application. One common end effector is a simplified version of the hand, which can grasp and carry different objects. Robotic hands often have built-in pressure sensors that tell the computer how hard the robot is gripping a particular object. This keeps the robot from dropping or breaking whatever it’s carrying. Other end effectors include blowtorches, drills and spray painters.

Industrial robots are designed to do exactly the same thing, in a controlled environment, over and over again. For example, a robot might twist the caps onto peanut butter jars coming down an assembly line. To teach a robot how to do its job, the programmer guides the arm through the motions using a handheld controller. The robot stores the exact sequence of movements in its memory, and does it again and again every time a new unit comes down the assembly line.

Most industrial robots work in auto assembly lines, putting cars together. Robots can do a lot of this work more efficiently than human beings because they are so precise. They always drill in the exactly the same place, and they always tighten bolts with the same amount of force, no matter how many hours they’ve been working. Manufacturing robots are also very important in the computer industry. It takes an incredibly precise hand to put together a tiny microchip.

This article can be found at: http://electronics.howstuffworks.com/robot.htm/

Memories from the Ashes by King Ink, (Sky Pirate Scribe)

Posted on , updated on by Computron

I don’t remember the sun. The first time word and meaning became one. But whatever thought I had could not hold true to the feast before me. I would like to say how the fingers of heaven reach out through the black smoke of the valley torn from battle around me. How my comrades glisten with the sweat of death and the valor of up rising beside me. But alas, it is not and I am alone.

So come lie by my side and watch this sun as it will set but not rise, not rise again for me. Not rise again for the day, the day of days, the day of pride and remembering. The day of courage and change. Of love and truth. A truth so stubborn that still it burns from beneath the silent ocean that flows to the ground around me.

Terra Firma be mine. Hold me now that I have fallen. Forgive me for what I could not be. Listen to these humble words and with them hold this proof, this testament. Be my witness, my child, that I may pass on the truth of truths, I am alive.

I live, but I only now know for certain at this, my end. Listen for me as I could not back when the sweet dew of truth found its way to my lips kissed with the words of Darla. So decadent this taste that my mouth froze solid my actions, my voice and lowered my head to hide my thoughts.

Scream for me and the years I watched. Be a shaft of molten rock that explodes into the sky. Be a tower and rise throughout the universe for all to know that what had been said has been proven and now is done, that you, that we, are alive.

Invasion Of The Robots

Posted on , updated on by Computron

by Michael Kanellos – Staff Writer, CNET News.com
March 10, 4:00 AM PT
The robots are coming. And when they get here, they will take out the trash. Mobile, intelligent robots that can perform tasks usually reserved for humans are starting to creep into mainstream society and could become a multibillion-dollar market in a few years.

iRobot says it has sold hundreds of thousands of units of the Roomba, a self-guided, self-propelled vacuum cleaner that sells for around $200, in just one year.

Other inventors are eyeing the health care market. Joe Engelberger, widely known as the father of robotics, is trying to get funding to build robots that will dress, cook for and generally take care of senior citizens. Home health care robots are being tested in Japan, while U.S. hospitals are already using machines to deliver charts, carry medicines or even assist in surgery.

“Nursing homes or live-in help is expensive, and you have personality conflicts,” Engelberger said. “The technology is available. It takes very good engineering, but it does not take invention.”

Another potentially large market exists in creating machines that can operate in hazardous or extreme environments. Workhorse Technologies, founded by Carnegie Mellon University professor William “Red” Whittaker, is working on robots that can map mine shafts. He came up with the idea after Pennsylvania’s Quecreek mine accident in 2002, in which nine miners were trapped for four days as the result of faulty maps.

Whittaker has also created robots that can drive harvesters, clear out sewer lines and clean up nuclear waste.

“When you are in those commodity enterprises and you can introduce efficiency, it does not matter whether it is carrying stuff out of a surface mine for less dollars per ton per mile or whether it is a greater productivity out of the machine in harvest,” Whittaker said. “Any small differences mean a lot, and these technologies can mean larger differences.”

Carnegie Mellon’s technological prowess in this area will be tested this weekend in the DARPA Grand Challenge, when driverless, robotic cars will race from Los Angeles to Las Vegas for a $1 million prize. The university’s Red Team Racing is the favorite. Other contestants include academics from the California Institute of Technology, a team of brothers from upstate New York and a group of students from Palos Verdes High School near Los Angeles.

Evolving automatons
The surge in robot activity is at least partly the result of steady improvements in performance and steadily dropping costs for processors, sensors, navigation software and the other technologies required to put a mobile robot together.

On the performance side, for instance, Seegrid, co-founded by Carnegie Mellon professor Hans Moravec, has developed software that allows a mobile device to create a dense 3D map of a hallway or room after a single pass. Global positioning systems, too, can pinpoint a robot or any other object anywhere on the globe within 10 centimeters, and on-board processors, which crunch sensor data and coordinate a robot’s movements, also continue to increase in performance.

And parts are getting much cheaper. Although robot researchers had to develop their own components in the past, today’s business is attracting chip suppliers and software developers such as Intel, Microsoft and Texas Instruments, as well as a number of start-ups.

Likewise, robot makers are working with other industries to lower manufacturing costs. The basis of the Roomba came out of robotic cleaning machines developed for Johnson Wax, and iRobot worked with Hasbro for three and a half years to learn low-cost manufacturing of toys.

Just as important as performance and costs, from a sales perspective, is customer satisfaction. Robot developers have adjusted their products to meet practical customer needs rather than simply using the machines to showcase a company’s technological abilities or as entertainment devices.

“The industry has disappointed for 40 years,” said Colin Angle, CEO of iRobot. “Ever since Rosie from ‘The Jetsons,’ robots have been the next big thing, but the business case was never there. It is easy to build a robot that is prohibitively expensive.”

iRobot’s PackBot is designed with practicality in mind. It’s a 40-pound battlefield robot designed to perform reconnaissance missions, help wounded soldiers, find chemical leaks and deliver equipment, all over rough, unpredictable terrain.

“One took a 25-foot fall and righted itself,” during an operation recently in Afghanistan, Angle said. “It is an incredibly mobile 800MHz Linux machine.”

PackBots aren’t cheap: They cost between $50,000 and $100,000 apiece. But their main customer–the U.S. government–seems happy. Besides deploying PackBots in Afghanistan and Iraq, the Army has given iRobot $25 million to develop automated battlefield vehicles.

Another recent success is the Predator, an unmanned plane used to attack al-Qaida in Yemen and other locations. The Department of Homeland Security is expected to issue several large research grants to this project in coming years.

“The sky is the limit, but it depends on the robotics entrepreneurs taking a much more customer-oriented approach,” said Kishore Rao, a senior associate at investment firm Trident Capital. The company put some of its capital behind iRobot but acknowledges that the number of VC-backed robot firms “can be counted on one hand.”

Bio of the ‘bot
The idea of automatons that can perform various tasks has been around since ancient Egypt. The word “robot,” however, is of relatively recent vintage, coined by Czech playwright Karel Capek in the 1921 play “R.U.R.”

The first commercial robots appeared in the early 1960s as the world was consumed with the Atomic Age science of the Cold War. Unimation, founded by Engelberger, created robotic manufacturing arms, while Barrett Electronics came out with a driverless electric cart for grocery warehouses that was navigated by signal-emitting wires in the floor.

It wasn’t an easy sell. “I had to go to 46 different companies, including GM and IBM, before I got some money from a railroad company,” Engelberger recalled. Although GM passed the first time, it eventually became the first company to install a Unimation machine.

Although robotic start-ups have spun out of CalTech and the Massachusetts Institute of Technology, one of the largest concentrations is in Pittsburgh. Since Westinghouse funded the development of the robotics program at Carnegie Mellon 25 years ago, roughly 30 robotics companies have set up shop in the region, according to Bill Thomasmeyer, president of the Robotics Foundry, which is trying to establish a robot economy in Western Pennsylvania.

Among the regional residents is Bombardier Transportation, which makes the people movers in airports. “They are looking to expand to downtown transportation,” Thomasmeyer said, an effort that will involve technologies to avoid inevitable obstacles.

Robots still are not a force in the global economy. In all, North American robotics manufacturers ship about $1 billion worth of products a year, according to Robotic Industries Association spokesman Jeff Burnstein. Other statistics show that the international market approaches $5 billion.

The vast majority of the revenue derives from limited-function devices used in packing or manufacturing plants, but versatile robots have entered the market in the last few years.

The da Vinci Surgical System from Intuitive Surgical, for example, is a set of precision robotic hands for doctors. The system, which costs a little more than $1 million, can drill through bone or make incisions.

Surgery is made far less intrusive because the machine can accurately control its movements and “see” in 3D through graphical images. That, in turn, makes recuperation quicker, less painful and cheaper, according to the company. Around 192 da Vinci systems are in use at hospitals to date.

The market for personal and mobile robots could grow to $5.4 billion this year and become larger than the industrial, nonmobile robot market, according to Dan Kara, president of Robotics Trends, which holds conferences and promotes the industry. By 2010, that figure will approach $17 billion, Kara said.

While some say such projections are overly optimistic, Kara can point to anecdotal evidence that robot fever is catching. About 68,000 attended Robodex in Japan last year, he said, and the sales numbers of Roomba and da Vinci are tough to argue with.

Similarities to PC industry
“If we were sitting here 10 years ago, I think no one would have really had a clear sense of what is the content of an intelligent robot,” said Whittaker, who believes that the economics of the robot market could function a lot like those of the PC industry in 20 or so years.

For the business to reach a full-fledged boom, however, some key problems must be solved. Communication and coordination remains a challenge, and such issues are being tackled by several scientists working on systems patterned after the swarming of insects.

Grippers also need work. Mobile robots like the PackBot or like those from Workhorse are good at taking pictures or delivering items, but picking things up is another matter.

Still, robot capabilities are growing rapidly. A 1,500-gram human brain can churn at about 100 trillion instructions a second, according to a paper recently published by Carnegie Mellon’s Moravec–nearly three times the power of the Earth Simulator, the world’s most powerful computer. Under Moore’s Law, processing performance could increase to the point where machines can work almost as well as the human brain.

“Better yet, sufficiently useful robots don’t need full human-scale brainpower,” Moravec wrote in his paper. “Commercial and research experience convinces me that mental power like that of a small guppy, about 1,000 MIPS, will suffice to guide mobile utility robots reliably through unfamiliar surroundings, suiting them for jobs in hundreds of thousands of industrial locations and eventually hundreds of millions of homes.”

The human brain aside, anthropomorphism will grab a piece of the market. Sony, Honda and some other Japanese companies are marketing robot companions, and a $99 “RoboSapien” will be coming soon from tech-toy company Wow Wee.

Mimicking human behavior in most robots remains complex, however, and the demand remains low. “You can get a robot to speak with you, but you can’t get it to talk Spinoza with you,” Engelberger said.

Another absent human characteristic is more obvious: legs. While some experimental robots have legs that mimic how geckos or crabs walk, wheels can work as well in almost every environment and are a lot easier to engineer.

“Legs in my mind are for Hollywood,” Angle said.

The original article can be found at: CNET.com