Visual inspection

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Visual inspection is a common method of quality control, data acquisition, and data analysis. Visual Inspection, used in maintenance of facilities, mean inspection of equipment and structures using either or all of raw human senses such as vision, hearing, touch and smell and/or any non-specialized inspection equipment. Inspections requiring Ultrasonic, X-Ray equipment, Infrared, etc. are not typically regarded as visual inspection as these Inspection methodologies require specialized equipment, training and certification.

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Quality control

A study of the visual inspection of small integrated circuits found that the modal duration of eye fixations of trained inspectors was about 200 ms. The most accurate inspectors made the fewest eye fixations and were the fastest. When the same chip was judged more than once by an individual inspector the consistency of judgment was very high whereas the consistency between inspectors was somewhat less. Variation by a factor of six in inspection speed led to variation of less than a factor of two in inspection accuracy. Visual inspection had a false positive rate of 2% and a false negative rate of 23%. [1]

Humorous terminology

To do an eyeball search is to look for something specific in a mass of code or data with one's own eyes, as opposed to using some sort of pattern matching software like grep or any other automated search tool. Also known as vgrep or ogrep, i.e., "visual/optical grep". [2] See also vdiff.

"Eyeballing" is the most common and readily available method of initial data assessment. [3] This method is effective for identifying patterns or anomalies in complex data but can be time-intensive and error-prone. [4] Although low-cost and adaptable, its efficiency and ROI often fall short compared to automated tools, which offer greater scalability and consistency. [5] However, switching from manual visual inspection to automated methods depends on the task's complexity, scale, and the balance between upfront costs and long-term efficiency. [6]

Experts in pattern recognition maintain that the "eyeball" technique is still the most effective procedure for searching arbitrary, possibly unknown structures in data. [7]

In the military, applying this sort of search to real-world terrain is often referred to as "using the Mark I Eyeball" device (pronounced as Mark One Eyeball), the U.S. military adopting it in 1950s. [8] The term is an allusion on military nomenclature, "Mark I" being the first version of a military vehicle or weapon.

See also

Related Research Articles

Computer vision tasks include methods for acquiring, processing, analyzing, and understanding digital images, and extraction of high-dimensional data from the real world in order to produce numerical or symbolic information, e.g. in the form of decisions. "Understanding" in this context signifies the transformation of visual images into descriptions of the world that make sense to thought processes and can elicit appropriate action. This image understanding can be seen as the disentangling of symbolic information from image data using models constructed with the aid of geometry, physics, statistics, and learning theory.

<span class="mw-page-title-main">Machine vision</span> Technology and methods used to provide imaging-based automatic inspection and analysis

Machine vision is the technology and methods used to provide imaging-based automatic inspection and analysis for such applications as automatic inspection, process control, and robot guidance, usually in industry. Machine vision refers to many technologies, software and hardware products, integrated systems, actions, methods and expertise. Machine vision as a systems engineering discipline can be considered distinct from computer vision, a form of computer science. It attempts to integrate existing technologies in new ways and apply them to solve real world problems. The term is the prevalent one for these functions in industrial automation environments but is also used for these functions in other environment vehicle guidance.

<span class="mw-page-title-main">Nondestructive testing</span> Evaluating the properties of a material, component, or system without causing damage

Nondestructive testing (NDT) is any of a wide group of analysis techniques used in science and technology industry to evaluate the properties of a material, component or system without causing damage. The terms nondestructive examination (NDE), nondestructive inspection (NDI), and nondestructive evaluation (NDE) are also commonly used to describe this technology. Because NDT does not permanently alter the article being inspected, it is a highly valuable technique that can save both money and time in product evaluation, troubleshooting, and research. The six most frequently used NDT methods are eddy-current, magnetic-particle, liquid penetrant, radiographic, ultrasonic, and visual testing. NDT is commonly used in forensic engineering, mechanical engineering, petroleum engineering, electrical engineering, civil engineering, systems engineering, aeronautical engineering, medicine, and art. Innovations in the field of nondestructive testing have had a profound impact on medical imaging, including on echocardiography, medical ultrasonography, and digital radiography.

<span class="mw-page-title-main">Iris recognition</span> Method of biometric identification

Iris recognition is an automated method of biometric identification that uses mathematical pattern-recognition techniques on video images of one or both of the irises of an individual's eyes, whose complex patterns are unique, stable, and can be seen from some distance. The discriminating powers of all biometric technologies depend on the amount of entropy they are able to encode and use in matching. Iris recognition is exceptional in this regard, enabling the avoidance of "collisions" even in cross-comparisons across massive populations. Its major limitation is that image acquisition from distances greater than a meter or two, or without cooperation, can be very difficult. However, the technology is in development and iris recognition can be accomplished from even up to 10 meters away or in a live camera feed.

A visual comparison is to compare two or more things by eye. This might be done by placing them side by side; by overlaying them; by alternating an image or by presenting each image to a separate eye.

<span class="mw-page-title-main">Bates method</span> Ineffective alternative eyesight improvement therapy

The Bates method is an ineffective and potentially dangerous alternative therapy aimed at improving eyesight. Eye-care physician William Horatio Bates (1860–1931) held the erroneous belief that the extraocular muscles caused changes in focus and that "mental strain" caused abnormal action of these muscles; hence he believed that relieving such "strain" would cure defective vision. In 1952, optometry professor Elwin Marg wrote of Bates, "Most of his claims and almost all of his theories have been considered false by practically all visual scientists."

<span class="mw-page-title-main">Inspection</span> Organized examination or formal evaluation exercise

An inspection is, most generally, an organized examination or formal evaluation exercise. In engineering activities inspection involves the measurements, tests, and gauges applied to certain characteristics in regard to an object or activity. The results are usually compared to specified requirements and standards for determining whether the item or activity is in line with these targets, often with a Standard Inspection Procedure in place to ensure consistent checking. Inspections are usually non-destructive.

<span class="mw-page-title-main">Eye examination</span> Series of tests assessing vision and pertaining to the eyes

An eye examination, commonly known as an eye test, is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations of the eyes. Eye examinations are primarily performed by an optometrist, ophthalmologist, or an orthoptist. Health care professionals often recommend that all people should have periodic and thorough eye examinations as part of routine primary care, especially since many eye diseases are asymptomatic. Typically, a healthy individual who otherwise has no concerns with their eyes receives an eye exam once in their 20s and twice in their 30s.

<span class="mw-page-title-main">Eye tracking</span> Measuring the point of gaze or motion of an eye relative to the head

Eye tracking is the process of measuring either the point of gaze or the motion of an eye relative to the head. An eye tracker is a device for measuring eye positions and eye movement. Eye trackers are used in research on the visual system, in psychology, in psycholinguistics, marketing, as an input device for human-computer interaction, and in product design. In addition, eye trackers are increasingly being used for assistive and rehabilitative applications such as controlling wheelchairs, robotic arms, and prostheses. Recently, eye tracking has been examined as a tool for the early detection of autism spectrum disorder. There are several methods for measuring eye movement, with the most popular variant using video images to extract eye position. Other methods use search coils or are based on the electrooculogram.

Enterprise content management (ECM) extends the concept of content management by adding a timeline for each content item and, possibly, enforcing processes for its creation, approval, and distribution. Systems using ECM generally provide a secure repository for managed items, analog or digital. They also include one methods for importing content to manage new items, and several presentation methods to make items available for use. Although ECM content may be protected by digital rights management (DRM), it is not required. ECM is distinguished from general content management by its cognizance of the processes and procedures of the enterprise for which it is created.

<span class="mw-page-title-main">Eye movement</span> Movement of the eyes

Eye movement includes the voluntary or involuntary movement of the eyes. Eye movements are used by a number of organisms to fixate, inspect and track visual objects of interests. A special type of eye movement, rapid eye movement, occurs during REM sleep.

<span class="mw-page-title-main">Boresight (firearm)</span>

Boresighting is a method of visually pre-aligning a firearm barrel's bore axis with the target, in order to more easily zero the gunsight. The process is usually performed on a rifle, and can be accomplished either with the naked eye, or with a specialized device called a boresighter.

<span class="mw-page-title-main">Visual field test</span> Eye examination that can detect dysfunction in central and peripheral vision

A visual field test is an eye examination that can detect dysfunction in central and peripheral vision which may be caused by various medical conditions such as glaucoma, stroke, pituitary disease, brain tumours or other neurological deficits. Visual field testing can be performed clinically by keeping the subject's gaze fixed while presenting objects at various places within their visual field. Simple manual equipment can be used such as in the tangent screen test or the Amsler grid. When dedicated machinery is used it is called a perimeter.

<span class="mw-page-title-main">Eye movement in music reading</span> Role of the eyes in reading music

Eye movement in music reading is the scanning of a musical score by a musician's eyes. This usually occurs as the music is read during performance, although musicians sometimes scan music silently to study it. The phenomenon has been studied by researchers from a range of backgrounds, including cognitive psychology and music education. These studies have typically reflected a curiosity among performing musicians about a central process in their craft, and a hope that investigating eye movement might help in the development of more effective methods of training musicians' sight reading skills.

Eye movement in reading involves the visual processing of written text. This was described by the French ophthalmologist Louis Émile Javal in the late 19th century. He reported that eyes do not move continuously along a line of text, but make short, rapid movements (saccades) intermingled with short stops (fixations). Javal's observations were characterised by a reliance on naked-eye observation of eye movement in the absence of technology. From the late 19th to the mid-20th century, investigators used early tracking technologies to assist their observation, in a research climate that emphasised the measurement of human behaviour and skill for educational ends. Most basic knowledge about eye movement was obtained during this period. Since the mid-20th century, there have been three major changes: the development of non-invasive eye-movement tracking equipment; the introduction of computer technology to enhance the power of this equipment to pick up, record, and process the huge volume of data that eye movement generates; and the emergence of cognitive psychology as a theoretical and methodological framework within which reading processes are examined. Sereno & Rayner (2003) believed that the best current approach to discover immediate signs of word recognition is through recordings of eye movement and event-related potential.

Weld quality assurance is the use of technological methods and actions to test or assure the quality of welds, and secondarily to confirm the presence, location and coverage of welds. In manufacturing, welds are used to join two or more metal surfaces. Because these connections may encounter loads and fatigue during product lifetime, there is a chance they may fail if not created to proper specification.

Underwater searches are procedures to find a known or suspected target object or objects in a specified search area under water. They may be carried out underwater by divers, manned submersibles, remotely operated underwater vehicles, or autonomous underwater vehicles, or from the surface by other agents, including surface vessels, aircraft and cadaver dogs.

<span class="mw-page-title-main">Sensor-based sorting</span>

Sensor-based sorting, is an umbrella term for all applications in which particles are detected using a sensor technique and rejected by an amplified mechanical, hydraulic or pneumatic process.

<span class="mw-page-title-main">Humphrey visual field analyser</span> Tool used by eye care professionals

Humphrey field analyser (HFA) is a tool for measuring the human visual field that is commonly used by optometrists, orthoptists and ophthalmologists, particularly for detecting monocular visual field.

References

  1. J. W. Schoonahd; J. D. Gould; L. A. Miller (July 1973), "Studies of Visual Inspection", Ergonomics, 16 (4), Taylor & Francis: 365–379, doi:10.1080/00140137308924528, PMID   28086275
  2. Jargon File , version 4.4.6, 25 Oct 2003
  3. Srinika Jayaratne, Rona L. Levy (1979) "Empirical Clinical Practice", ISBN   0-231-04188-8, p. 110
  4. Hrymak, Victor; Vries, Jam (2019). "The development and trial of systematic visual search: a visual inspection method designed to improve current workplace risk assessment practice". Policy and Practice in Health and Safety. 18 (1). Taylor & Francis: 9–24. doi:10.1080/14773996.2019.1708615.
  5. "Visual Inspection System Cost Breakdown & Calculating ROI". Averroes. Jun 18, 2018. Retrieved Nov 26, 2024.
  6. Behrisch, Michael; Krueger, Robert (2018). Visual Pattern-Driven Exploration of Big Data (Report). Germany: IEEE. pp. 1–11. doi:10.1109/BDVA.2018.8534028.
  7. Hans-Jürgen Zimmermann (2001) "Fuzzy Set Theory--and Its Applications", ISBN   0-7923-7435-5, p. 278
  8. "Contemporary Geodesy" (Proceedings of a Conference Held at the Harvard College Observatory - Smithsonian Astrophysical Observatory, Cambridge, MA, December 1–2, 1958). P. 68 says: "Now the first type of optical tracking, the most elementary, is that using merely the naked eye — as I heard a Navy man say the other day, 'Mark I eyeball' ".