{"id":45884,"date":"2023-04-22T01:47:37","date_gmt":"2023-04-22T06:47:37","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-to-use-ultrasonic-sensor\/"},"modified":"2025-01-21T07:24:24","modified_gmt":"2025-01-21T12:24:24","slug":"how-to-use-ultrasonic-sensor","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/vi\/how-to-use-ultrasonic-sensor\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m hi\u1ec7u qu\u1ea3"},"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 \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3. Ch\u00fang ho\u1ea1t \u0111\u1ed9ng b\u1eb1ng c\u00e1ch ph\u00e1t ra m\u1ed9t xung si\u00eau \u00e2m ng\u1eafn v\u00e0 sau \u0111\u00f3 \u0111o th\u1eddi gian s\u00f3ng \u00e2m ph\u1ea3n x\u1ea1 tr\u1edf l\u1ea1i c\u1ea3m bi\u1ebfn.  Vi\u1ec7c hi\u1ec3u r\u00f5 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng v\u00e0 c\u00e1ch s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m m\u1edf ra nhi\u1ec1u \u1ee9ng d\u1ee5ng trong cu\u1ed9c s\u1ed1ng, t\u1eeb \u0111o m\u1ee9c ch\u1ea5t l\u1ecfng \u0111\u1ebfn h\u1ed7 tr\u1ee3 \u0111\u1ed7 xe t\u1ef1 \u0111\u1ed9ng. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd h\u01b0\u1edbng d\u1eabn chi ti\u1ebft c\u00e1ch s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m.<\/p>\n<h3>Nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u1ea3m bi\u1ebfn si\u00eau \u00e2m<\/h3>\n<p>C\u1ea3m bi\u1ebfn si\u00eau \u00e2m th\u01b0\u1eddng g\u1ed3m m\u1ed9t b\u1ed9 ph\u00e1t v\u00e0 m\u1ed9t b\u1ed9 thu s\u00f3ng \u00e2m. B\u1ed9 ph\u00e1t t\u1ea1o ra m\u1ed9t xung si\u00eau \u00e2m \u1edf t\u1ea7n s\u1ed1 cao (th\u01b0\u1eddng n\u1eb1m ngo\u00e0i ng\u01b0\u1ee1ng nghe c\u1ee7a con ng\u01b0\u1eddi). S\u00f3ng \u00e2m n\u00e0y truy\u1ec1n trong kh\u00f4ng kh\u00ed v\u00e0 khi g\u1eb7p v\u1eadt c\u1ea3n s\u1ebd ph\u1ea3n x\u1ea1 l\u1ea1i. B\u1ed9 thu c\u1ee7a c\u1ea3m bi\u1ebfn s\u1ebd nh\u1eadn \u0111\u01b0\u1ee3c s\u00f3ng ph\u1ea3n x\u1ea1 n\u00e0y. B\u1eb1ng c\u00e1ch \u0111o th\u1eddi gian t\u1eeb l\u00fac ph\u00e1t xung \u0111\u1ebfn l\u00fac nh\u1eadn \u0111\u01b0\u1ee3c t\u00edn hi\u1ec7u ph\u1ea3n h\u1ed3i, k\u1ebft h\u1ee3p v\u1edbi t\u1ed1c \u0111\u1ed9 \u00e2m thanh trong kh\u00f4ng kh\u00ed, ta c\u00f3 th\u1ec3 t\u00ednh to\u00e1n kho\u1ea3ng c\u00e1ch \u0111\u1ebfn v\u1eadt c\u1ea3n.<\/p>\n<h3>C\u00e1c lo\u1ea1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m ph\u1ed5 bi\u1ebfn<\/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, ph\u1ea1m vi \u0111o, k\u00edch th\u01b0\u1edbc v\u00e0 \u1ee9ng d\u1ee5ng. 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 \u0111o (cm)<\/th>\n<th>\u01afu \u0111i\u1ec3m<\/th>\n<th>Nh\u01b0\u1ee3c \u0111i\u1ec3m<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>HC-SR04<\/td>\n<td>40<\/td>\n<td>2-400<\/td>\n<td>Gi\u00e1 r\u1ebb, d\u1ec5 s\u1eed d\u1ee5ng<\/td>\n<td>\u0110\u1ed9 ch\u00ednh x\u00e1c h\u1ea1n ch\u1ebf<\/td>\n<\/tr>\n<tr>\n<td>JSN-SR04T<\/td>\n<td>40<\/td>\n<td>2-450<\/td>\n<td>Ch\u1ed1ng n\u01b0\u1edbc<\/td>\n<td>Ph\u1ea1m vi \u0111o h\u1eb9p h\u01a1n m\u1ed9t s\u1ed1 lo\u1ea1i kh\u00e1c<\/td>\n<\/tr>\n<tr>\n<td>US-100<\/td>\n<td>40<\/td>\n<td>2-450<\/td>\n<td>\u0110\u1ed9 ch\u00ednh x\u00e1c cao h\u01a1n HC-SR04<\/td>\n<td>Gi\u00e1 th\u00e0nh cao h\u01a1n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>K\u1ebft n\u1ed1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m v\u1edbi vi \u0111i\u1ec1u khi\u1ec3n<\/h3>\n<p>Vi\u1ec7c k\u1ebft n\u1ed1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m v\u1edbi vi \u0111i\u1ec1u khi\u1ec3n kh\u00e1 \u0111\u01a1n gi\u1ea3n. V\u00ed d\u1ee5, v\u1edbi c\u1ea3m bi\u1ebfn HC-SR04 v\u00e0 Arduino, ta c\u1ea7n 4 ch\u00e2n k\u1ebft n\u1ed1i: VCC, GND, Trigger v\u00e0 Echo.  Ch\u00e2n Trigger d\u00f9ng \u0111\u1ec3 k\u00edch ho\u1ea1t c\u1ea3m bi\u1ebfn ph\u00e1t xung si\u00eau \u00e2m, c\u00f2n ch\u00e2n Echo d\u00f9ng \u0111\u1ec3 nh\u1eadn t\u00edn hi\u1ec7u ph\u1ea3n h\u1ed3i.<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Ch\u00e2n c\u1ea3m bi\u1ebfn<\/th>\n<th>Ch\u00e2n Arduino<\/th>\n<th>Ch\u1ee9c n\u0103ng<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>VCC<\/td>\n<td>5V<\/td>\n<td>Ngu\u1ed3n<\/td>\n<\/tr>\n<tr>\n<td>GND<\/td>\n<td>GND<\/td>\n<td>\u0110\u1ea5t<\/td>\n<\/tr>\n<tr>\n<td>Trig<\/td>\n<td>K\u1ef9 thu\u1eadt s\u1ed1 (v\u00ed d\u1ee5: 7)<\/td>\n<td>K\u00edch ho\u1ea1t<\/td>\n<\/tr>\n<tr>\n<td>Echo<\/td>\n<td>K\u1ef9 thu\u1eadt s\u1ed1 (v\u00ed d\u1ee5: 8)<\/td>\n<td>Nh\u1eadn t\u00edn hi\u1ec7u<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>L\u1eadp tr\u00ecnh \u0111i\u1ec1u khi\u1ec3n c\u1ea3m bi\u1ebfn si\u00eau \u00e2m<\/h3>\n<p>Sau khi k\u1ebft n\u1ed1i ph\u1ea7n c\u1ee9ng, ta c\u1ea7n l\u1eadp tr\u00ecnh cho vi \u0111i\u1ec1u khi\u1ec3n \u0111\u1ec3 \u0111i\u1ec1u khi\u1ec3n c\u1ea3m bi\u1ebfn v\u00e0 x\u1eed l\u00fd d\u1eef li\u1ec7u. V\u00ed d\u1ee5 v\u1edbi Arduino, ta c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng th\u01b0 vi\u1ec7n <code>NewPing<\/code> \u0111\u1ec3 \u0111\u01a1n gi\u1ea3n h\u00f3a vi\u1ec7c l\u1eadp tr\u00ecnh.  Code m\u1eabu s\u1ebd bao g\u1ed3m vi\u1ec7c g\u1eedi xung k\u00edch ho\u1ea1t, \u0111o th\u1eddi gian ph\u1ea3n h\u1ed3i v\u00e0 t\u00ednh to\u00e1n kho\u1ea3ng c\u00e1ch.<\/p>\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 th\u1ef1c t\u1ebf, bao g\u1ed3m:<\/p>\n<ul>\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>Robot tr\u00e1nh v\u1eadt c\u1ea3n<\/li>\n<li>\u0110o l\u01b0u l\u01b0\u1ee3ng<\/li>\n<li>C\u1ea3m bi\u1ebfn ti\u1ec7m c\u1eadn<\/li>\n<\/ul>\n<h3>Kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1 th\u01b0\u1eddng g\u1eb7p<\/h3>\n<p>M\u1ed9t s\u1ed1 v\u1ea5n \u0111\u1ec1 th\u01b0\u1eddng g\u1eb7p khi s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m bao g\u1ed3m nhi\u1ec5u t\u1eeb c\u00e1c ngu\u1ed3n \u00e2m thanh kh\u00e1c, b\u1ec1 m\u1eb7t v\u1eadt c\u1ea3n qu\u00e1 nh\u1eb5n ho\u1eb7c qu\u00e1 g\u1ed3 gh\u1ec1, v\u00e0 g\u00f3c \u0111o kh\u00f4ng ph\u00f9 h\u1ee3p. C\u1ea7n l\u01b0u \u00fd c\u00e1c y\u1ebfu t\u1ed1 n\u00e0y \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 ch\u00ednh x\u00e1c c\u1ee7a ph\u00e9p \u0111o.<\/p>\n<p>Vi\u1ec7c s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m mang l\u1ea1i nhi\u1ec1u l\u1ee3i \u00edch trong vi\u1ec7c \u0111o kho\u1ea3ng c\u00e1ch v\u00e0 ph\u00e1t hi\u1ec7n v\u1eadt c\u1ea3n.  T\u1eeb vi\u1ec7c n\u1eafm v\u1eefng nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng, c\u00e1ch k\u1ebft n\u1ed1i v\u00e0 l\u1eadp tr\u00ecnh, ng\u01b0\u1eddi d\u00f9ng c\u00f3 th\u1ec3 \u1ee9ng d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m v\u00e0o nhi\u1ec1u d\u1ef1 \u00e1n v\u00e0 h\u1ec7 th\u1ed1ng kh\u00e1c nhau, t\u1eeb \u0111\u01a1n gi\u1ea3n \u0111\u1ebfn ph\u1ee9c t\u1ea1p. Hy v\u1ecdng b\u00e0i vi\u1ebft n\u00e0y \u0111\u00e3 cung c\u1ea5p cho b\u1ea1n nh\u1eefng ki\u1ebfn th\u1ee9c c\u1ea7n thi\u1ebft \u0111\u1ec3 b\u1eaft \u0111\u1ea7u s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m m\u1ed9t c\u00e1ch hi\u1ec7u qu\u1ea3.<\/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 \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3. Ch\u00fang ho\u1ea1t \u0111\u1ed9ng b\u1eb1ng c\u00e1ch ph\u00e1t ra m\u1ed9t xung si\u00eau \u00e2m ng\u1eafn v\u00e0 sau \u0111\u00f3 \u0111o th\u1eddi gian s\u00f3ng \u00e2m ph\u1ea3n x\u1ea1 tr\u1edf l\u1ea1i c\u1ea3m bi\u1ebfn. Vi\u1ec7c hi\u1ec3u r\u00f5 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng<\/p>\n","protected":false},"author":1,"featured_media":26464,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6406],"tags":[],"class_list":["post-45884","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\/45884","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=45884"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/45884\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media\/26464"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media?parent=45884"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/categories?post=45884"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/tags?post=45884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}