The process of having a machine or machines accomplish tasks hither to performed wholly or partly by humans. As used here, a machine refers to any inanimate electromechanical device such as a robot or computer. As a technology, automation can be applied to almost any human endeavor, from manufacturing to clerical and administrative tasks. An example of automation is the heating andair-conditioning system in the modern household. After initial programming by the occupant, these systems keep the house at a constant desired temperature regardless of the conditions outside.
. Z3 `% {' S& L- \1 K% H( c- Z8 g7 I- u z1 {3 E/ \. H
The fundamental constituents of any automated process are (1) a powersource, (2) a feedback control mechanism, and (3) a programmable command (see illustration) structure. Programmability does not necessarily imply an electronic computer. For example, the Jacquard loom, developed at the beginning of the nineteenth century, used metal plates with holes to control the weaving process. Nonetheless, the advent of World War II and the advances madein electronic computation and feedback have certainly contributed to the growth of automation. While feedback is usually associated with more advanced forms of automation, so-called open-loop automated tasksare possible. Here, the automated process proceeds without any directand continuous assessment of the effect of the automated activity. For example, an automated car wash typically completes its task with nocontinuous or final assessment of the cleanliness of the automobile.
7 c: F1 B i8 T2 `
! F! H' j- ?& y3 ZElements of an automated system.
( T" z5 f) H$ L1 ^1 N" m1 v4 x
Because of the growing ubiquity of automation, any categorization of automated tasks and processes is incomplete. Nonetheless, such a categorization can be attempted by recognizing two distinct groups, automated manufacturing and automated information processing and control. Automated manufacturing includes automated machine tools, assembly lines, robotic assembly machines,automated storage-retrieval systems, integrated computer-aided designand computer-aided manufacturing (CAD/CAM), automatic inspection andtesting, and automated agricultural equipment (used, for example, incrop harvesting). Automated information processing and control includes automatic order processing, word processing and text editing, automatic data processing, automatic flight control, automatic automobile cruise control, automatic airline reservation systems, automatic mail sorting machines, automated planet exploration (for example, the rover vehicle,
Sojourner, on the
Mars Pathfinder mission), automated electric utility distribution systems, and automated bank teller machines.
: t, v; e! N% g, M& b1 q
! b Z; ~4 h4 p6 _; @ hA major issue in the design of systems involving both human and automated machines concerns allocating functions between the two. This allocation can be static or dynamic. Static allocation is fixed; that is, the separation of responsibilities between human and machine do not changewith time. Dynamic allocation implies that the functions allocated tohuman and machine are subject to change. Historically, static allocation began with reference to lists of activities which summarized the relative advantages of humans and machines with respect to avariety of activities. For example, at present humans appear to surpass machines in the ability to reason inductively, that is, to proceed from the particular to the general. Machines, however, surpass humans in the ability to handle complex operations and to do many different things atonce, that is, to engage in parallel processing. Dynamic function allocation can be envisioned as operating through a formulation which continuously determines which agent (human or machine) is free to attend to a particular task or function. In addition, constraints such as the workload implied by the human attending to the task as opposed to the machine can be considered.
$ r. _6 \: U3 L( I F7 z3 W+ p* w# K- T4 Q! g J3 h4 \
It has long been the goal in the area of automation to create systems which could react to unforeseen events with reasoning and problem-solving abilities akin to those of an experienced human, that is, to exhibit artificial intelligence. Indeed,the study of artificial intelligence is devoted to developing computer programs that can mimic the product of intelligent human problem solving, perception, andthought. For example, such a system could be envisioned to perform much like a human copilot in airline operations, communicating with the pilot via voice input and spoken output, assuming cockpit duties when and where assigned, and relieving the pilot of many duties. Indeed, such an automated system has been studied and named a pilot's associate. Machines exhibiting artificial intelligence obviously render the sharp demarcation between functions better performed by humans than by machines somewhat moot. While the early promise of artificial intelligence has not been fully realized in practice, certain applications in more restrictive domain shave been highly successful. These include the use of expert systems,which mimic the activity of human experts in limited domains, such as diagnosis of infectious diseases or providing guidance for oil exploration and drilling. Expert systems generally operate by (1)replacing human activity entirely, (2) providing advice or decision support, or (3) training a novice human in a particular field.
, g/ { _) E! g
* q4 v- j2 E) s
[
本帖最后由 MichaelHsu170 于 2008-3-3 23:14 编辑 ]
