{"id":2530,"date":"2019-08-13T09:05:38","date_gmt":"2019-08-13T09:05:38","guid":{"rendered":"http:\/\/teachcomputerscience.com\/?p=511"},"modified":"2024-07-24T10:36:01","modified_gmt":"2024-07-24T10:36:01","slug":"sensors","status":"publish","type":"post","link":"https:\/\/teachcomputerscience.com\/sensors\/","title":{"rendered":"Sensors"},"content":{"rendered":"<div class=\"gb-container gb-container-9b351a66 upsell-block\"><div class=\"gb-inside-container\">\n<div class=\"gb-grid-wrapper gb-grid-wrapper-0a346dc9\">\n<div class=\"gb-grid-column gb-grid-column-0bfa7b23\"><div class=\"gb-container gb-container-0bfa7b23\"><div class=\"gb-inside-container\">\n\n<h2 class=\"gb-headline gb-headline-f9b33c3b gb-headline-text\">GCSE Computer Hardware Resources (14-16 years)<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>An editable PowerPoint lesson presentation<\/li><li>Editable revision handouts<\/li><li>A glossary which covers the key terminologies of the module<\/li><li>Topic mindmaps for visualising the key concepts<\/li><li>Printable flashcards to help students engage active recall and confidence-based repetition<\/li><li>A quiz with accompanying answer key to test knowledge and understanding of the module<\/li><\/ul>\n\n\n<div class=\"gb-button-wrapper gb-button-wrapper-b4228078\">\n\n<a class=\"gb-button gb-button-df369f5c gb-button-text\" href=\"https:\/\/teachcomputerscience.com\/gcse\/computer-hardware\/\">View GCSE Computer Hardware Resources<\/a>\n\n<\/div>\n<\/div><\/div><\/div>\n\n<div class=\"gb-grid-column gb-grid-column-a8ed3fda\"><div class=\"gb-container gb-container-a8ed3fda\"><div class=\"gb-inside-container\">\n\n<h2 class=\"gb-headline gb-headline-3c47ffae gb-headline-text\">A-Level Output Devices Resources (16-18 years)<\/h2>\n\n\n\n<ul class=\"wp-block-list\"><li>An editable PowerPoint lesson presentation<\/li><li>Editable revision handouts<\/li><li>A glossary which covers the key terminologies of the module<\/li><li>Topic mindmaps for visualising the key concepts<\/li><li>Printable flashcards to help students engage active recall and confidence-based repetition<\/li><li>A quiz with accompanying answer key to test knowledge and understanding of the module<\/li><\/ul>\n\n\n<div class=\"gb-button-wrapper gb-button-wrapper-0cb0d4d5\">\n\n<a class=\"gb-button gb-button-5dcffeaf gb-button-text\" href=\"https:\/\/teachcomputerscience.com\/a-level\/contemporary-processors\/output-devices\/\">View A-Level Output Devices Resources<\/a>\n\n<\/div>\n<\/div><\/div><\/div>\n<\/div>\n<\/div><\/div>\n\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Sensors<\/strong>&nbsp;are advanced devices that are used to sense and react to signals, either electrical or optical.&nbsp; A&nbsp;sensor&nbsp;translates the physical characteristic of the input into a signal which can be calculated electrically.&nbsp; For example, the mercury in a glass thermometer expands and compresses the liquid in order to represent the calculated temperature, which can be viewed on the graduated glass tube.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u00a0<\/strong>A sensor is a device that senses and reacts to some type of input from the physical environment.\u00a0 Types of input are as follows: heat, light, moisture, motion, pressure, or any other environmental phenomenon.\u00a0 The result is typically a signal that is either translated to a human-readable display at the sensor location or sent electronically over a network for reading or further processing.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Properties of a Good Sensor<\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li>It is sensitive to the measured property.<\/li><li>It is sensitive to any other property likely to be encountered in its application.<\/li><li>It does not influence the measured property.<\/li><\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A sensor\u2019s sensitivity specifies how much the sensor\u2019s output varies in relation to the extent that the input quantity being measured varies.&nbsp; For example, if the mercury in the thermometer moves 1 cm when the temperature varies by 1 C, the sensitivity can be represented as 1cm\/C.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Examples of Sensors<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The input is the temperature in a mercury-based glass thermometer.\u00a0 The liquid contained expands and compresses in response, making the level higher or lower on the marked gauge, which is human-readable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An oxygen sensor in a car&#8217;s emission <a class=\"wpil_internal_link\" style=\"display: inline !important; width: auto !important;\" data-wpil-post-to-id=\"2547\" href=\"http:\/\/teachcomputerscience.com\/control-systems\/\" target=\"_blank\" rel=\"noopener noreferrer\">control system<\/a> senses the gasoline\/oxygen ratio, usually through a chemical reaction that produces a voltage.\u00a0 A computer in the engine reads the voltage and, if the mixture is not ideal, readjusts the balance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Motion sensors in various systems, including home security lights, automatic doors, and bathroom fixtures, typically transmit some type of energy like&nbsp;microwaves,&nbsp;ultrasonic waves,&nbsp;or light beams, and sense when the flow of energy is hampered by something entering its path.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A\u00a0photosensor\u00a0senses the presence of visible light,\u00a0infrared transmission\u00a0(IR), and\/or ultraviolet (UV) energy.<\/p>\n\n\n\n<div class=\"wp-block-image\"><figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2019\/08\/044-internet.png\" alt=\"Sensors\u00a0are advanced devices that are used to sense and react to signals, either electrical or optical.\" class=\"wp-image-5784\" width=\"249\" height=\"249\" title=\"\" srcset=\"https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2019\/08\/044-internet.png 512w, https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2019\/08\/044-internet-150x150.png 150w, https:\/\/teachcomputerscience.com\/wp-content\/uploads\/2019\/08\/044-internet-300x300.png 300w\" sizes=\"auto, (max-width: 249px) 100vw, 249px\" \/><\/figure><\/div>\n\n\n\n<h3 class=\"wp-block-heading\">Sensor Selection Criteria<\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li>Accuracy \u2013 measurements are expected to be accurate<\/li><li>Calibration \u2013 readings changes with time, so it should be regularly calibrated accordingly<\/li><li>Cost \u2013 should be within budget<\/li><li>Environmental condition \u2013 should comply with temperature or humidity limits<\/li><li>Range \u2013 should include clearly defined limits of measurement<\/li><li>Repeatability \u2013 variable readings should be repeatable under the same environment<\/li><li>Resolution &#8211; should be able to reliably sense the smallest increment<\/li><\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Sensor Classification<\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li>Primary input quantity<\/li><li>Transduction principles \u2013 fundamental criteria followed for an efficient approach<\/li><li>Material and Technology \u2013 usually chosen by a development engineering group<\/li><li>Property\n<ul>\n<li>Temperature \u2013 Thermistors, IC (Integrated Circuits)<\/li>\n<li>Pressure \u2013 Fiber optic, LVDT (Linear Variable Differential Transformer)<\/li>\n<li>Flow \u2013 Electromagnetic, Thermal mass<\/li>\n<li>Level Sensors \u2013 Differential pressure, Thermal displacement<\/li>\n<li>Proximity and displacement \u2013 Photoelectric sensors, Ultrasonic<\/li>\n<li>Biosensors \u2013 Resonant mirrors, Surface plasmon resonance<\/li>\n<li>Image \u2013 Charge coupled devices,&nbsp;CMOS (Complementary Metal Oxide Semiconductor)<\/li>\n<li>Gas and chemical \u2013 Semiconductors, Conductance<\/li>\n<li>Acceleration \u2013 Gyroscopes, Accelerometers<\/li>\n<li>Others \u2013 Moisture sensors,&nbsp;Speed sensors<\/li>\n<\/ul>\n<\/li><li>Application\n<ul>\n<li>Industrial process control, measurement, and automation<\/li>\n<li>Non-industrial use \u2013 Aircraft, Automobiles<\/li>\n<\/ul>\n<\/li><li>Power or Energy Supply Requirement\n<ul>\n<li>Active Sensor \u2013 requires power supply like LiDAR (Light Detection and Ranging), Photoconductive cells<\/li>\n<li>Passive Sensor \u2013 does not require a power supply: examples include Radiometers, Film photography sensors<\/li>\n<\/ul>\n<\/li><\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Sensor Group Classification<\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li>Accelerometers \u2013 based on Micro Electro Mechanical sensor technology. They are utilised for patient monitoring purposes (like pacemakers) as well as for vehicle dynamic systems.<\/li><li>Biosensors \u2013 based on electrochemical technology. They are utilised for food testing, medical care devices, water testing, and biological warfare agent detection.<\/li><li>Image Sensors \u2013 based on CMOS&nbsp;technology. They are utilised in consumer electronics,&nbsp;biometrics, traffic and security surveillance, and PC imaging.<\/li><li>Motion Detectors \u2013 based on Infra-Red, Ultrasonic, and Microwave \/ Radar Technology. They are utilised in video games and simulations, light activation, and security detection.<\/li><\/ul>\n\n\n\n<h3 class=\"gb-headline gb-headline-14bb4302 gb-headline-text\"><strong>Further Readings:<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\"><li><a href=\"https:\/\/en.wikipedia.org\/wiki\/Sensor\" target=\"_blank\" rel=\"noopener\">Sensor<\/a><\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Sensors&nbsp;are advanced devices that are used to sense and react to signals, either electrical or optical.&nbsp; A&nbsp;sensor&nbsp;translates the physical characteristic of the input into a signal which can be calculated electrically.&nbsp; For example, the mercury in a glass thermometer expands and compresses the liquid in order to represent the calculated temperature, which can be viewed &#8230; <\/p>\n<p class=\"read-more-container\"><a title=\"Sensors\" class=\"read-more button\" href=\"https:\/\/teachcomputerscience.com\/sensors\/\" aria-label=\"Read more about Sensors\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_monsterinsights_skip_tracking":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[26],"tags":[204,47],"class_list":["post-2530","post","type-post","status-publish","format-standard","hentry","category-hardware-software","tag-article","tag-hide-old-upsell","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-50"],"acf":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2530","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/comments?post=2530"}],"version-history":[{"count":2,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2530\/revisions"}],"predecessor-version":[{"id":605577,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/posts\/2530\/revisions\/605577"}],"wp:attachment":[{"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/media?parent=2530"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/categories?post=2530"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/teachcomputerscience.com\/wp-json\/wp\/v2\/tags?post=2530"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}