{"id":44388,"date":"2023-04-25T14:56:15","date_gmt":"2023-04-25T19:56:15","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/what-is-an-ultrasonic-sensor\/"},"modified":"2025-01-21T07:28:43","modified_gmt":"2025-01-21T12:28:43","slug":"what-is-an-ultrasonic-sensor","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/vi\/what-is-an-ultrasonic-sensor\/","title":{"rendered":"Kh\u00e1m ph\u00e1 C\u1ea3m bi\u1ebfn Si\u00eau \u00c2m: Nguy\u00ean l\u00fd v\u00e0 \u1ee8ng d\u1ee5ng"},"content":{"rendered":"<p>C\u1ea3m bi\u1ebfn si\u00eau \u00e2m l\u00e0 m\u1ed9t thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed s\u1eed d\u1ee5ng s\u00f3ng \u00e2m thanh \u1edf t\u1ea7n s\u1ed1 cao h\u01a1n ph\u1ea1m vi nghe \u0111\u01b0\u1ee3c c\u1ee7a con ng\u01b0\u1eddi (th\u01b0\u1eddng tr\u00ean 20kHz) \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3. Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a n\u00f3 d\u1ef1a tr\u00ean vi\u1ec7c ph\u00e1t ra m\u1ed9t xung si\u00eau \u00e2m v\u00e0 \u0111o th\u1eddi gian s\u00f3ng \u00e2m ph\u1ea3n x\u1ea1 tr\u1edf l\u1ea1i c\u1ea3m bi\u1ebfn.  B\u1eb1ng c\u00e1ch bi\u1ebft t\u1ed1c \u0111\u1ed9 \u00e2m thanh trong m\u00f4i tr\u01b0\u1eddng v\u00e0 th\u1eddi gian n\u00e0y, ta c\u00f3 th\u1ec3 t\u00ednh to\u00e1n ch\u00ednh x\u00e1c kho\u1ea3ng c\u00e1ch \u0111\u1ebfn v\u1eadt th\u1ec3. C\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i trong nhi\u1ec1u l\u0129nh v\u1ef1c, t\u1eeb \u0111o m\u1ee9c ch\u1ea5t l\u1ecfng, \u0111\u1ed7 xe t\u1ef1 \u0111\u1ed9ng \u0111\u1ebfn robot v\u00e0 y t\u1ebf.<\/p>\n<h3>Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng<\/h3>\n<p>C\u1ea3m bi\u1ebfn si\u00eau \u00e2m ho\u1ea1t \u0111\u1ed9ng d\u1ef1a tr\u00ean nguy\u00ean l\u00fd \u0111\u1ecbnh v\u1ecb b\u1eb1ng ti\u1ebfng vang (echolocation), t\u01b0\u01a1ng t\u1ef1 nh\u01b0 c\u00e1ch d\u01a1i v\u00e0 c\u00e1 heo s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u1ecbnh h\u01b0\u1edbng. C\u1ea3m bi\u1ebfn g\u1ed3m m\u1ed9t b\u1ed9 ph\u1eadn ph\u00e1t v\u00e0 m\u1ed9t b\u1ed9 ph\u1eadn thu s\u00f3ng si\u00eau \u00e2m. B\u1ed9 ph\u1eadn ph\u00e1t t\u1ea1o ra m\u1ed9t xung si\u00eau \u00e2m ng\u1eafn, xung n\u00e0y truy\u1ec1n \u0111i trong kh\u00f4ng kh\u00ed cho \u0111\u1ebfn khi g\u1eb7p m\u1ed9t v\u1eadt c\u1ea3n.  Khi g\u1eb7p v\u1eadt c\u1ea3n, s\u00f3ng \u00e2m b\u1ecb ph\u1ea3n x\u1ea1 l\u1ea1i v\u00e0 \u0111\u01b0\u1ee3c b\u1ed9 ph\u1eadn thu c\u1ee7a c\u1ea3m bi\u1ebfn ghi nh\u1eadn.  Th\u1eddi gian gi\u1eefa l\u00fac ph\u00e1t xung v\u00e0 l\u00fac nh\u1eadn \u0111\u01b0\u1ee3c t\u00edn hi\u1ec7u ph\u1ea3n x\u1ea1 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 th\u1eddi gian bay (Time of Flight &#8211; TOF).<\/p>\n<h3>C\u00f4ng th\u1ee9c t\u00ednh kho\u1ea3ng c\u00e1ch<\/h3>\n<p>Kho\u1ea3ng c\u00e1ch \u0111\u1ebfn v\u1eadt th\u1ec3 \u0111\u01b0\u1ee3c t\u00ednh theo c\u00f4ng th\u1ee9c:<\/p>\n<p>Kho\u1ea3ng c\u00e1ch = (T\u1ed1c \u0111\u1ed9 \u00e2m thanh x Th\u1eddi gian bay) \/ 2<\/p>\n<p>H\u1ec7 s\u1ed1 2 xu\u1ea5t hi\u1ec7n do s\u00f3ng \u00e2m \u0111\u00e3 \u0111i c\u1ea3 qu\u00e3ng \u0111\u01b0\u1eddng \u0111\u1ebfn v\u1eadt th\u1ec3 v\u00e0 quay tr\u1edf l\u1ea1i. T\u1ed1c \u0111\u1ed9 \u00e2m thanh trong kh\u00f4ng kh\u00ed ph\u1ee5 thu\u1ed9c v\u00e0o nhi\u1ec7t \u0111\u1ed9 v\u00e0 \u00e1p su\u1ea5t, nh\u01b0ng th\u01b0\u1eddng \u0111\u01b0\u1ee3c l\u1ea5y x\u1ea5p x\u1ec9 l\u00e0 343 m\/s \u1edf \u0111i\u1ec1u ki\u1ec7n ti\u00eau chu\u1ea9n.<\/p>\n<h3>C\u00e1c lo\u1ea1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m<\/h3>\n<p>C\u00f3 nhi\u1ec1u lo\u1ea1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m kh\u00e1c nhau, \u0111\u01b0\u1ee3c ph\u00e2n lo\u1ea1i d\u1ef1a tr\u00ean t\u1ea7n s\u1ed1, k\u00edch th\u01b0\u1edbc, v\u00e0 ph\u1ea1m vi ho\u1ea1t \u0111\u1ed9ng.  M\u1ed9t s\u1ed1 lo\u1ea1i ph\u1ed5 bi\u1ebfn bao g\u1ed3m:<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Lo\u1ea1i c\u1ea3m bi\u1ebfn<\/th>\n<th>T\u1ea7n s\u1ed1 (kHz)<\/th>\n<th>Ph\u1ea1m vi ho\u1ea1t \u0111\u1ed9ng<\/th>\n<th>\u1ee8ng d\u1ee5ng<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>C\u1ea3m bi\u1ebfn t\u1ea7n s\u1ed1 th\u1ea5p<\/td>\n<td>40 &#8211; 60<\/td>\n<td>V\u00e0i m\u00e9t<\/td>\n<td>\u0110o m\u1ee9c ch\u1ea5t l\u1ecfng, ph\u00e1t hi\u1ec7n v\u1eadt c\u1ea3n<\/td>\n<\/tr>\n<tr>\n<td>C\u1ea3m bi\u1ebfn t\u1ea7n s\u1ed1 cao<\/td>\n<td>100 &#8211; 500<\/td>\n<td>V\u00e0i cm \u0111\u1ebfn v\u00e0i m\u00e9t<\/td>\n<td>\u0110o kho\u1ea3ng c\u00e1ch ch\u00ednh x\u00e1c, robot, y t\u1ebf<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>\u01afu \u0111i\u1ec3m v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m<\/h3>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>\u01afu \u0111i\u1ec3m<\/th>\n<th>Nh\u01b0\u1ee3c \u0111i\u1ec3m<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Gi\u00e1 th\u00e0nh r\u1ebb<\/td>\n<td>\u0110\u1ed9 ch\u00ednh x\u00e1c b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi nhi\u1ec7t \u0111\u1ed9, \u00e1p su\u1ea5t v\u00e0 \u0111\u1ed9 \u1ea9m<\/td>\n<\/tr>\n<tr>\n<td>D\u1ec5 s\u1eed d\u1ee5ng<\/td>\n<td>Kh\u00f4ng ho\u1ea1t \u0111\u1ed9ng t\u1ed1t trong m\u00f4i tr\u01b0\u1eddng c\u00f3 nhi\u1ec1u b\u1ee5i ho\u1eb7c v\u1eadt c\u1ea3n nh\u1ecf<\/td>\n<\/tr>\n<tr>\n<td>Ho\u1ea1t \u0111\u1ed9ng \u0111\u01b0\u1ee3c trong nhi\u1ec1u m\u00f4i tr\u01b0\u1eddng kh\u00e1c nhau<\/td>\n<td>G\u00f3c ph\u00e1t hi\u1ec7n h\u1ea1n ch\u1ebf<\/td>\n<\/tr>\n<tr>\n<td>Kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi m\u00e0u s\u1eafc ho\u1eb7c \u0111\u1ed9 trong su\u1ed1t c\u1ee7a v\u1eadt th\u1ec3<\/td>\n<td>Kh\u00f3 ph\u00e1t hi\u1ec7n v\u1eadt th\u1ec3 m\u1ec1m ho\u1eb7c c\u00f3 b\u1ec1 m\u1eb7t h\u1ea5p th\u1ee5 \u00e2m thanh t\u1ed1t<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>\u1ee8ng d\u1ee5ng c\u1ee7a c\u1ea3m bi\u1ebfn si\u00eau \u00e2m<\/h3>\n<p>C\u1ea3m bi\u1ebfn si\u00eau \u00e2m c\u00f3 r\u1ea5t nhi\u1ec1u \u1ee9ng d\u1ee5ng trong cu\u1ed9c s\u1ed1ng h\u00e0ng ng\u00e0y v\u00e0 trong c\u00f4ng nghi\u1ec7p, bao g\u1ed3m:<\/p>\n<ul>\n<li>\u0110o kho\u1ea3ng c\u00e1ch trong robot v\u00e0 xe t\u1ef1 h\u00e0nh<\/li>\n<li>\u0110o m\u1ee9c ch\u1ea5t l\u1ecfng trong b\u1ed3n ch\u1ee9a<\/li>\n<li>H\u1ec7 th\u1ed1ng h\u1ed7 tr\u1ee3 \u0111\u1ed7 xe<\/li>\n<li>Ph\u00e1t hi\u1ec7n v\u1eadt c\u1ea3n<\/li>\n<li>Y t\u1ebf (si\u00eau \u00e2m ch\u1ea9n \u0111o\u00e1n)<\/li>\n<\/ul>\n<p>T\u00f3m l\u1ea1i, c\u1ea3m bi\u1ebfn si\u00eau \u00e2m l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 \u0111o kho\u1ea3ng c\u00e1ch linh ho\u1ea1t, hi\u1ec7u qu\u1ea3 v\u00e0 chi ph\u00ed th\u1ea5p.  V\u1edbi nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng \u0111\u01a1n gi\u1ea3n nh\u01b0ng hi\u1ec7u qu\u1ea3, c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u00e3 v\u00e0 \u0111ang \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i trong nhi\u1ec1u l\u0129nh v\u1ef1c kh\u00e1c nhau, \u0111\u00f3ng g\u00f3p \u0111\u00e1ng k\u1ec3 v\u00e0o s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00f4ng ngh\u1ec7 hi\u1ec7n \u0111\u1ea1i.  Vi\u1ec7c hi\u1ec3u r\u00f5 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng, \u01b0u nh\u01b0\u1ee3c \u0111i\u1ec3m v\u00e0 \u1ee9ng d\u1ee5ng c\u1ee7a c\u1ea3m bi\u1ebfn si\u00eau \u00e2m s\u1ebd gi\u00fap ng\u01b0\u1eddi d\u00f9ng l\u1ef1a ch\u1ecdn v\u00e0 s\u1eed d\u1ee5ng thi\u1ebft b\u1ecb m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3 nh\u1ea5t.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>C\u1ea3m bi\u1ebfn si\u00eau \u00e2m l\u00e0 m\u1ed9t thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed s\u1eed d\u1ee5ng s\u00f3ng \u00e2m thanh \u1edf t\u1ea7n s\u1ed1 cao h\u01a1n ph\u1ea1m vi nghe \u0111\u01b0\u1ee3c c\u1ee7a con ng\u01b0\u1eddi (th\u01b0\u1eddng tr\u00ean 20kHz) \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3. Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a n\u00f3 d\u1ef1a tr\u00ean vi\u1ec7c ph\u00e1t ra m\u1ed9t xung si\u00eau \u00e2m v\u00e0 \u0111o<\/p>\n","protected":false},"author":1,"featured_media":19558,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6406],"tags":[],"class_list":["post-44388","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","prodpage-classic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/44388","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/comments?post=44388"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/44388\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media\/19558"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media?parent=44388"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/categories?post=44388"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/tags?post=44388"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}