Перевод текстов "Robotics" и "Programmable Controllers" с английского на русский язык, страница 2

MIT designed a type of rubber "skin" for a robotic hand which contains a layer of fine wires that can sense the items being handled more precisely than earlier devices. The computer system connected to the hand constructs and displays the image of the object being touched.

robots are emerging in nonindustrial areas of our lives, such as domestic use, medical applications, and earth, sea, and space exploration.

Japan is the world's leader in the manufacture and use of industrial robots. About 65 percent of the robots are in Japan; the United -States is the next largest user. Statistics show that in 1986 there were over 100,000 industrial robots in the world. Projections indicate that at the current growth rate there will be over 200,000 robots in 1990. The cost of an industrial robot is anywhere from $25,000 to $125,000. Major suppliers of robots include: Hitachi, Kawasaki, and Mitsubishi in Japan; Cincinnati Mila-cron, GMF Robotics, and DeVilbiss in the U.S.;

Volkswagen in West Germany; and Renault in France.

Programmable Controllers

Two important aspects of running an industrial plant are monitoring and controlling the activities of the machinery. These jobs are being taken over by the programmable controller. A programmable controller is a computer-regulated unit that consists of a microprocessor, an input and output module, and a power supply (Figure 7).

A programmable controller is used: (a) to control on/off functions of switches and relays; and (b) to control processes (process control).

The microprocessor of the programmable controller is programmed with a keyboard that can be attached to it when needed. The keyboard is nnt actnallv nart nf the rTintrnllF-r nnrc;

FIGURE 7

The Babcock & Wilcox Company's Loose Parts Monitoring System III, a programmable controller, uses sophisticated computer analysis techniques to evaluate metal-to-metal impacts of loose parts caught in the high velocity flows of nuclear steam systems. It provides real-time estimates of the location and damage potential of loose parts. (Courtesy of The Babcock & Wilcox Co.)

the programming is complete, the keyboard can be removed, and the programmable controller is still functional.

The advantage of the programmable controller is that its microprocessor can be programmed to reflect any desired cause and effect relationship, e.g., throwing Switch 1 starts Motor 2. The programmable controller can also be reprogrammed should any changes be necHere is a simple description of how the programmable controller is used to regulate on/off functions of two motors. Suppose two separate switches control two separate motors: S1 (Switch 1) controls M1 (Motor 1); and S2 (Switch 2) controls M2 (Motor 2). Rather than directly connecting S1 to M1, they are connected via the programmable controller; the same is true for S2 and M2. When the programmable controller receives the signal that S1 is switched on, it processes that signal and outputs it to start M1.

Why not directly connect the input to the output? What if you wanted Switch 1 to control Motor 2? It is much easier to reprogram the programmable controller than it is to rewire the circuit. Imagine if there were ten or twenty or even one hundred inputs and outputs. It is much easier to direct a programmable controller than to redesign the physical system.

Process control is the monitoring and controlling of various processes in a system's operation. For example, a programmable controller can play an important part in regulating furnace temperature for melting glass. Basically, a "set point" is programmed into the programmable controller, such as a specific temperature for the glass-melting furnace. The furnace continually sends temperature data signals back to the programmable controller. The programmable controller compares these signals to its preprogrammed set point. If the signals do not match—perhaps the temperature has risen—the programmable controller sends a signal to a control element that adjusts the furnace temperature accordingly. One programmable controller can control many process-control systems, a more complex task than controlling on/off operations.