{"id":47884,"date":"2023-04-21T23:51:05","date_gmt":"2023-04-22T04:51:05","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-to-make-homemade-ultrasonic-sensor\/"},"modified":"2025-01-21T07:19:48","modified_gmt":"2025-01-21T12:19:48","slug":"how-to-make-homemade-ultrasonic-sensor","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/vi\/how-to-make-homemade-ultrasonic-sensor\/","title":{"rendered":"T\u1ef1 ch\u1ebf c\u1ea3m bi\u1ebfn si\u00eau \u00e2m: H\u01b0\u1edbng d\u1eabn chi ti\u1ebft"},"content":{"rendered":"<p>Vi\u1ec7c t\u1ef1 ch\u1ebf c\u1ea3m bi\u1ebfn si\u00eau \u00e2m c\u00f3 th\u1ec3 l\u00e0 m\u1ed9t d\u1ef1 \u00e1n th\u00fa v\u1ecb v\u00e0 mang t\u00ednh gi\u00e1o d\u1ee5c, tuy nhi\u00ean \u0111\u00f2i h\u1ecfi s\u1ef1 t\u1ec9 m\u1ec9 v\u00e0 ki\u1ebfn th\u1ee9c nh\u1ea5t \u0111\u1ecbnh v\u1ec1 \u0111i\u1ec7n t\u1eed. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd h\u01b0\u1edbng d\u1eabn b\u1ea1n c\u00e1ch l\u00e0m m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u01a1n gi\u1ea3n t\u1ea1i nh\u00e0.<\/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 ho\u1ea1t \u0111\u1ed9ng d\u1ef1a tr\u00ean nguy\u00ean l\u00fd s\u00f3ng \u00e2m. N\u00f3 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.  Bi\u1ebft \u0111\u01b0\u1ee3c 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>Linh ki\u1ec7n c\u1ea7n chu\u1ea9n b\u1ecb<\/h3>\n<p>\u0110\u1ec3 l\u00e0m c\u1ea3m bi\u1ebfn si\u00eau \u00e2m, b\u1ea1n c\u1ea7n chu\u1ea9n b\u1ecb nh\u1eefng linh ki\u1ec7n sau:<\/p>\n<ul>\n<li>B\u1ed9 ph\u00e1t si\u00eau \u00e2m (40kHz)<\/li>\n<li>B\u1ed9 thu si\u00eau \u00e2m (40kHz)<\/li>\n<li>Vi \u0111i\u1ec1u khi\u1ec3n (v\u00ed d\u1ee5: Arduino Uno)<\/li>\n<li>\u0110i\u1ec7n tr\u1edf<\/li>\n<li>T\u1ee5 \u0111i\u1ec7n<\/li>\n<li>D\u00e2y n\u1ed1i<\/li>\n<li>Breadboard (t\u00f9y ch\u1ecdn)<\/li>\n<\/ul>\n<h3>S\u01a1 \u0111\u1ed3 m\u1ea1ch \u0111i\u1ec7n<\/h3>\n<p>S\u01a1 \u0111\u1ed3 m\u1ea1ch \u0111i\u1ec7n kh\u00e1 \u0111\u01a1n gi\u1ea3n. B\u1ed9 ph\u00e1t si\u00eau \u00e2m \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i v\u1edbi m\u1ed9t ch\u00e2n digital c\u1ee7a vi \u0111i\u1ec1u khi\u1ec3n. B\u1ed9 thu si\u00eau \u00e2m \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i v\u1edbi m\u1ed9t ch\u00e2n digital kh\u00e1c.  \u0110i\u1ec7n tr\u1edf v\u00e0 t\u1ee5 \u0111i\u1ec7n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 b\u1ea3o v\u1ec7 vi \u0111i\u1ec1u khi\u1ec3n v\u00e0 \u1ed5n \u0111\u1ecbnh t\u00edn hi\u1ec7u.<\/p>\n<h3>L\u1eadp tr\u00ecnh vi \u0111i\u1ec1u khi\u1ec3n<\/h3>\n<p>B\u1ea1n c\u1ea7n l\u1eadp tr\u00ecnh vi \u0111i\u1ec1u khi\u1ec3n \u0111\u1ec3 \u0111i\u1ec1u khi\u1ec3n b\u1ed9 ph\u00e1t v\u00e0 b\u1ed9 thu si\u00eau \u00e2m.  \u0110o\u1ea1n code s\u1ebd k\u00edch ho\u1ea1t b\u1ed9 ph\u00e1t \u0111\u1ec3 g\u1eedi m\u1ed9t xung si\u00eau \u00e2m ng\u1eafn. Sau \u0111\u00f3, vi \u0111i\u1ec1u khi\u1ec3n s\u1ebd l\u1eafng nghe t\u00edn hi\u1ec7u ph\u1ea3n x\u1ea1 t\u1eeb b\u1ed9 thu. Th\u1eddi gian gi\u1eefa vi\u1ec7c ph\u00e1t xung v\u00e0 nh\u1eadn t\u00edn hi\u1ec7u ph\u1ea3n x\u1ea1 s\u1ebd \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u00ednh to\u00e1n kho\u1ea3ng c\u00e1ch.<\/p>\n<pre><code class=\"language-c++\">\/\/ V\u00ed d\u1ee5 code Arduino (\u0111\u01a1n gi\u1ea3n h\u00f3a)\nconst int trigPin = 9;\nconst int echoPin = 10;\nlong duration;\nint distance;\n\nvoid setup() {\n  pinMode(trigPin, OUTPUT);\n  pinMode(echoPin, INPUT);\n  Serial.begin(9600);\n}\n\nvoid loop() {\n  digitalWrite(trigPin, LOW);\n  delayMicroseconds(2);\n  digitalWrite(trigPin, HIGH);\n  delayMicroseconds(10);\n  digitalWrite(trigPin, LOW);\n  duration = pulseIn(echoPin, HIGH);\n  distance = duration * 0.34 \/ 2;\n  Serial.print(\"Kho\u1ea3ng c\u00e1ch: \");\n  Serial.print(distance);\n  Serial.println(\" cm\");\n  delay(100);\n}\n<\/code><\/pre>\n<h3>Ki\u1ec3m tra v\u00e0 hi\u1ec7u ch\u1ec9nh<\/h3>\n<p>Sau khi l\u1eafp r\u00e1p v\u00e0 l\u1eadp tr\u00ecnh, b\u1ea1n c\u1ea7n ki\u1ec3m tra c\u1ea3m bi\u1ebfn b\u1eb1ng c\u00e1ch \u0111\u1eb7t m\u1ed9t v\u1eadt c\u1ea3n \u1edf ph\u00eda tr\u01b0\u1edbc v\u00e0 quan s\u00e1t k\u1ebft qu\u1ea3 \u0111o \u0111\u01b0\u1ee3c.  B\u1ea1n c\u00f3 th\u1ec3 hi\u1ec7u ch\u1ec9nh \u0111\u1ed9 ch\u00ednh x\u00e1c b\u1eb1ng c\u00e1ch thay \u0111\u1ed5i c\u00e1c gi\u00e1 tr\u1ecb trong code.<\/p>\n<h3>\u01afu \u0111i\u1ec3m v\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a c\u1ea3m bi\u1ebfn t\u1ef1 ch\u1ebf<\/h3>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>\u0110\u1eb7c \u0111i\u1ec3m<\/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>Chi ph\u00ed<\/td>\n<td>Th\u1ea5p<\/td>\n<td>\u0110\u1ed9 ch\u00ednh x\u00e1c c\u00f3 th\u1ec3 th\u1ea5p h\u01a1n c\u1ea3m bi\u1ebfn th\u01b0\u01a1ng m\u1ea1i<\/td>\n<\/tr>\n<tr>\n<td>\u0110\u1ed9 ph\u1ee9c t\u1ea1p<\/td>\n<td>\u0110\u01a1n gi\u1ea3n<\/td>\n<td>C\u1ea7n ki\u1ebfn th\u1ee9c v\u1ec1 \u0111i\u1ec7n t\u1eed v\u00e0 l\u1eadp tr\u00ecnh<\/td>\n<\/tr>\n<tr>\n<td>Kh\u1ea3 n\u0103ng t\u00f9y ch\u1ec9nh<\/td>\n<td>Cao<\/td>\n<td>M\u1ea5t th\u1eddi gian ch\u1ebf t\u1ea1o<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Vi\u1ec7c t\u1ef1 l\u00e0m c\u1ea3m bi\u1ebfn si\u00eau \u00e2m c\u00f3 th\u1ec3 g\u1eb7p m\u1ed9t s\u1ed1 kh\u00f3 kh\u0103n, \u0111\u1eb7c bi\u1ec7t l\u00e0 trong vi\u1ec7c l\u1ef1a ch\u1ecdn linh ki\u1ec7n ph\u00f9 h\u1ee3p v\u00e0 hi\u1ec7u ch\u1ec9nh \u0111\u1ed9 ch\u00ednh x\u00e1c. Tuy nhi\u00ean, \u0111\u00e2y l\u00e0 m\u1ed9t d\u1ef1 \u00e1n th\u00fa v\u1ecb gi\u00fap b\u1ea1n hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u1ea3m bi\u1ebfn si\u00eau \u00e2m v\u00e0 r\u00e8n luy\u1ec7n k\u1ef9 n\u0103ng \u0111i\u1ec7n t\u1eed. N\u1ebfu c\u1ea7n \u0111\u1ed9 ch\u00ednh x\u00e1c cao v\u00e0 \u1ed5n \u0111\u1ecbnh, b\u1ea1n n\u00ean c\u00e2n nh\u1eafc s\u1eed d\u1ee5ng c\u1ea3m bi\u1ebfn si\u00eau \u00e2m th\u01b0\u01a1ng m\u1ea1i.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Vi\u1ec7c t\u1ef1 ch\u1ebf c\u1ea3m bi\u1ebfn si\u00eau \u00e2m c\u00f3 th\u1ec3 l\u00e0 m\u1ed9t d\u1ef1 \u00e1n th\u00fa v\u1ecb v\u00e0 mang t\u00ednh gi\u00e1o d\u1ee5c, tuy nhi\u00ean \u0111\u00f2i h\u1ecfi s\u1ef1 t\u1ec9 m\u1ec9 v\u00e0 ki\u1ebfn th\u1ee9c nh\u1ea5t \u0111\u1ecbnh v\u1ec1 \u0111i\u1ec7n t\u1eed. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd h\u01b0\u1edbng d\u1eabn b\u1ea1n c\u00e1ch l\u00e0m m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u01a1n gi\u1ea3n t\u1ea1i nh\u00e0. Nguy\u00ean l\u00fd<\/p>\n","protected":false},"author":1,"featured_media":26466,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6406],"tags":[],"class_list":["post-47884","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\/47884","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=47884"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/47884\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media\/26466"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media?parent=47884"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/categories?post=47884"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/tags?post=47884"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}