Robotics, welding using

C. Smith, Robotic Friction Stir Welding Using a Standard Industrial Robot, Proceedings of the Second International Symposium on Friction Stir Welding, June 2000 (Gothenberg, Sweden), TWI... 

Standard articulated robots consist of six axes. They are available on the market in a large variety of types and variants. Characterized by a cyhndrical working area occupying a relatively small volume, articulated robots easily allow failures to be repaired directly. Articulated robots are used primarily for spot welding, material handling, and painting as well as machining. 

Automation is a term introduced in the automotive industry in the mid-1940s. This pertains to the use of controlled mechanisms to replace human operators. Robots represent an important form of automation. The first robots were used about 1961 to unload die cast parts. Robots are computer-controlled devices that perform tasks that might otherwise be done by humans. They are particularly useful in hazardous environments, and for repetitive tasks that require more energy or concentration than a person can be expected to provide over large periods of time. Robots are widely used in the automotive industry for spray painting, welding, and a variety of assembly operations. Robots have been termed steel collar workers as opposed to blue collar workers. 

Robotic sealing in the body shop, like seam sealing and door assembly, is performed to seal out dust and moisture while protecting weld locations from corrosion due to the galvanization being burned off. The bead dispensed is nominally a 0.160-0.200 in. diameter, at velocities that approach 20 in./second. The robotic systems used in this system are similar to Fig. 1. 

Tiny machines such as Zettl s oscillator may be useful on their own but also in forming the components of more sophisticated instruments such as nanobots. Robotic automation is commonly employed in industrial factories to do jobs that require repetition or extreme precision, such as spot welding. Nanobots would have the added benefit of being able to function in otherwise inaccessibly small locations. Tasks for nanobots include scanning a load-bearing surface and looking for signs of structural failure that would be impossible for a human inspector to see. 

The human body, for instance, has sensors (eyes, ears, touch receptors in the skin, and so forth), a controller (the brain), and actuators (muscles) to react and respond to commands. These are the same basic concepts as the adaptive systems discussed in this chapter. Robots today, such as the welding machines used in industry or the toy dogs sold as pets, are extremely Umited in mobility and adaptability compared to humans. Yet smart materials, along with a design based on the sensory, nervous, and muscular systems of the body, could one day create an agile and adaptable robot. 

The third type of FSSW machine is a C-frame unit. The purpose of the C-frame is to contain the welding forces internal to the unit. This means that the robot or operator does not have to generate any of the forces required for the process. Thus, smaller robots can be used for C-frame FSSW than for FSW. The robot arm only manipulates the C-frame unit through space to the part that is to be welded. Robots that are used for RS W can also be used for FSSW. Typical C-frame FSSW units are shown in Fig. 11.7. 

FSW Robot System for Automobile Body Members, Proceedings of the Third International Symposium on Friction Stir Welding, Sept 2001 (Kobe, Japan), TWI M. Skiimer and R. Edwards, Improvement to the FSW Process Using the Self-Reacting Technology, Mater. Sci. Forum, Vol 426 32, 2003, p 2849-2854... 

The welds are inspected using focalised ultrasonic transducers, which employ the echographic technique, mounted on the robot A coupling fluid is installed between the transmitter and the weld to be checked using a small vessel containing this fluid This vessel is in contact with the wall of the zone to be inspected through a seal A visual inspection of the weld is also carried out by a CCTV camera... 

Stationary systems based on CO2 lasers and robot-controlled systems using solid-state lasers have been introduced into the industrial marketplace. Remote laser welding is the latest in a series of successful industrial laser solutions that have revolutionized sheet metal processing over the past 30 years. 

An end effector is the attachment at the end of a robot s arm that is used for a specific task such as holding a tool, painting, or welding. 

An end effector might also be a tool such as a welding gun. Welding is one of the most common uses of robots in industry. The automotive industry makes extensive use of robots in welding operations. Another very common use of robots is painting automobiles. In this case, the end effector is the paint-spraying apparatus. 

LEW is a versatile process and can be used to weld a variety of materials including carbon steels, stainless steel, titanium, aluminium, nickel alloys and plastics. Lasers are often used in high-volume production applications as they have high welding speeds and a level of automation which allows them to be used in numerically controlled machines and robots. They are also used to weld dissimilar metal combinations. 

Single chain robot manipulates are found in many different environments today. In industry, individual manipulators are used for welding, painting and some assembly operations. Their use in metal forging and machining continues as well. Robot manipulators also play an important part in current space exploration efforts and in future plans for space station operation. In many of these applications, the tip of the manipulator comes in contact with various objects in its environment, instantaneously creating a closed-chain configuraticMi. 

Garcia, P., M. J. Mines, K. S. Bower, J. Hill, J. Menon, E. Tremhlay, and B. Smith. 2009. Robotic laser tissue welding of sclera using chitosan films. Lasers in Surgery and Medicine 41 (l) 60-67. 

Moser L, Mitschang P and Schlarb A K (2008) Induction welding of thermoplastic polymer composites using robotic techniques, SAMPE J 44 43-49. 

Kurfess, T. R., ed. 2005. Robotics and Automation Handbook. Boca Raton, FL CRC Press. This title begins with a history of robotics and moves quickly into how to design, construct, enable, and control various types of robots. Examples are offered of the use of robots in specific industries, such as welding, surgery, assembly, etc. 

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