18-04-2012, 11:09 AM
Robotics
robots.doc (Size: 44.5 KB / Downloads: 60)
Robotics is the engineering science and technology of robots, and their design, manufacture, application, and structural disposition. The word robot was introduced to the public by Czech writer Karel Čapek in his play R.U.R. (Rossum's Universal Robots), published in 1920. The term "robotics" was coined by Isaac Asimov in his 1941 science fiction short-story "Liar!"
History
• In 1837, the story of the Golem of Prague, a humanoid artificial intelligence activated by inscribing Hebrew letters on its forehead, based on Jewish folklore, was created by Jewish German writer Berthold Auerbach for his novel Spinoza.
• In 1921, Czech writer Karel Čapek introduced the word "robot" in his play R.U.R. (Rossum's Universal Robots). The word "robot" comes from the word "robota", meaning, in Czech, "forced labour, drudgery".
• In 1927, the Maschinenmensch (“machine-human”), a gynoid humanoid robot, also called "Parody", "Futura", "Robotrix", or the "Maria impersonator" (played by German actress Brigitte Helm), the first and perhaps the most memorable depiction of a robot ever to appear on film, was depicted in Fritz Lang's film Metropolis.
Fully autonomous robots only appeared in the second half of the 20th century. The first digitally operated and programmable robot, the Unimate, was installed in 1961 to lift hot pieces of metal from a die casting machine and stack them. Today, commercial and industrial robots are in widespread use performing jobs more cheaply or more accurately and reliably than humans. They are also employed in jobs which are too dirty, dangerous, or dull to be suitable for humans. Robots are widely used in manufacturing, assembly, and packing; transport; earth and space exploration; surgery; weaponry; laboratory research; safety; and mass production of consumer and industrial goods.
1495 Designs for a humanoid robot Mechanical knight Leonardo da Vinci
1738 Mechanical duck that was able to eat, flap its wings, and excrete Digesting Duck Jacques de Vaucanson
1898 Nikola Tesla demonstrates first radio-controlled vessel. Teleautomaton Nikola Tesla
1921 First fictional automatons called "robots" appear in the play R.U.R. Rossum's Universal Robots Karel Čapek
1930s Humanoid robot exhibited at the 1939 and 1940 World's Fairs Elektro Westinghouse Electric Corporation
1948 Simple robots exhibiting biological behaviors Elsie and Elmer William Grey Walter
1956 First commercial robot, from the Unimation company founded by George Devol and Joseph Engelberger, based on Devol's patents Unimate George Devol
1961 First installed industrial robot. Unimate George Devol
1963 First palletizing robot[9] Palletizer Fuji Yusoki Kogyo
1973 First industrial robot with six electromechanically driven axes[10] Famulus KUKA Robot Group
1975 Programmable universal manipulation arm, a Unimation product PUMA Victor Scheinman
Structure
The structure of a robot is usually mostly mechanical and can be called a kinematic chain (its functionality being similar to the skeleton of the human body). The chain is formed of links (its bones), actuators (its muscles), and joints which can allow one or more degrees of freedom. Most contemporary robots use open serial chains in which each link connects the one before to the one after it. These robots are called serial robots and often resemble the human arm. Some robots, such as the Stewart platform, use a closed parallel kinematical chain. Other structures, such as those that mimic the mechanical structure of humans, various animals, and insects, are comparatively rare. However, the development and use of such structures in robots is an active area of research (e.g. biomechanics). Robots used as manipulators have an end effector mounted on the last link. This end effector can be anything from a welding device to a mechanical hand used to manipulate the environment.
Power source
At present; mostly (lead-acid) batteries are used, but potential power sources could be:
• pneumatic (compressed gases)
• hydraulics (compressed liquids)
• flywheel energy storage
• organic garbage (through anaerobic digestion)
• faces (human, animal); may be interesting in a military context as feces of small combat groups may be reused for the energy requirements of the robot assistant (see DEKA's project Slingshot stirling engine on how the system would operate)
• still untested energy sources (e.g. Nuclear Fusion reactors, ...)
• radioactive source (such as with the proposed Ford car of the '50s); to those proposed in movies such as Red Planet
Actuation
A robot leg powered by Air MusclesActuators are like the "muscles" of a robot, the parts which convert stored energy into movement. By far the most popular actuators are electric motors that spin a wheel or gear, and linear actuators that control industrial robots in factors. But there are some recent advances in alternative types of actuators, powered by electricity, chemicals, or compressed air:
Electric motors: The vast majority of robots use electric motors, often brushed and brushless DC motors in portable robots or AC motors in industrial robots and CNC machines.
Linear Actuators: Various types of linear actuators move in and out instead of by spinning, particularly when very large forces are needed such as with industrial robotics. They are typically powered by compressed air (pneumatic actuator) or an oil (hydraulic actuator).
Series Elastic Actuators: A spring can be designed as part of the motor actuator, to allow improved force control. It has been used in various robots, particularly walking humanoid robots
Air muscles: (Also known as Pneumatic Artificial Muscles) are special tubes that contract (typically up to 40%) when air is forced inside it. They have been used for some robot applications