{"id":45212,"date":"2023-04-22T03:01:16","date_gmt":"2023-04-22T08:01:16","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-to-make-an-ultrasonic-sensor\/"},"modified":"2025-01-21T07:17:49","modified_gmt":"2025-01-21T12:17:49","slug":"how-to-make-an-ultrasonic-sensor","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/vi\/how-to-make-an-ultrasonic-sensor\/","title":{"rendered":"T\u1ef1 ch\u1ebf t\u1ea1o c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u01a1n gi\u1ea3n"},"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 \u1edf t\u1ea7n s\u1ed1 cao h\u01a1n ng\u01b0\u1ee1ng nghe c\u1ee7a con ng\u01b0\u1eddi \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3.  Vi\u1ec7c t\u1ef1 ch\u1ebf t\u1ea1o m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u00f2i h\u1ecfi ki\u1ebfn th\u1ee9c v\u1ec1 \u0111i\u1ec7n t\u1eed v\u00e0 m\u1ed9t ch\u00fat kh\u00e9o l\u00e9o, nh\u01b0ng ho\u00e0n to\u00e0n c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n \u0111\u01b0\u1ee3c n\u1ebfu b\u1ea1n c\u00f3 \u0111\u1ee7 s\u1ef1 ki\u00ean nh\u1eabn v\u00e0 c\u00e1c linh ki\u1ec7n c\u1ea7n thi\u1ebft. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd h\u01b0\u1edbng d\u1eabn chi ti\u1ebft c\u00e1ch l\u00e0m m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u01a1n gi\u1ea3n.<\/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 ph\u1ea3n x\u1ea1 s\u00f3ng \u00e2m.  M\u1ed9t b\u1ed9 ph\u1eadn ph\u00e1t ra s\u00f3ng si\u00eau \u00e2m, v\u00e0 b\u1ed9 ph\u1eadn thu s\u1ebd l\u1eafng nghe ti\u1ebfng v\u1ecdng d\u1ed9i l\u1ea1i t\u1eeb v\u1eadt th\u1ec3. Th\u1eddi gian t\u1eeb l\u00fac ph\u00e1t s\u00f3ng \u0111\u1ebfn l\u00fac nh\u1eadn \u0111\u01b0\u1ee3c ti\u1ebfng v\u1ecdng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u00ednh to\u00e1n kho\u1ea3ng c\u00e1ch \u0111\u1ebfn v\u1eadt th\u1ec3, d\u1ef1a tr\u00ean t\u1ed1c \u0111\u1ed9 \u00e2m thanh trong m\u00f4i tr\u01b0\u1eddng.<\/p>\n<h3>Linh ki\u1ec7n c\u1ea7n thi\u1ebft<\/h3>\n<p>\u0110\u1ec3 l\u00e0m m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m, b\u1ea1n s\u1ebd c\u1ea7n nh\u1eefng linh ki\u1ec7n sau:<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Linh ki\u1ec7n<\/th>\n<th>M\u00f4 t\u1ea3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>B\u1ed9 ph\u00e1t si\u00eau \u00e2m (40kHz)<\/td>\n<td>Th\u01b0\u1eddng l\u00e0 lo\u1ea1i c\u1ea3m bi\u1ebfn si\u00eau \u00e2m HC-SR04.<\/td>\n<\/tr>\n<tr>\n<td>B\u1ed9 thu si\u00eau \u00e2m (40kHz)<\/td>\n<td>Th\u01b0\u1eddng \u0111i k\u00e8m v\u1edbi b\u1ed9 ph\u00e1t trong c\u00f9ng m\u1ed9t module.<\/td>\n<\/tr>\n<tr>\n<td>Vi \u0111i\u1ec1u khi\u1ec3n (Arduino Uno\/Nano)<\/td>\n<td>\u0110\u1ec3 \u0111i\u1ec1u khi\u1ec3n v\u00e0 x\u1eed l\u00fd t\u00edn hi\u1ec7u.<\/td>\n<\/tr>\n<tr>\n<td>\u0110i\u1ec7n tr\u1edf<\/td>\n<td>\u0110\u1ec3 h\u1ea1n ch\u1ebf d\u00f2ng \u0111i\u1ec7n.<\/td>\n<\/tr>\n<tr>\n<td>T\u1ee5 \u0111i\u1ec7n<\/td>\n<td>\u0110\u1ec3 l\u1ecdc nhi\u1ec5u.<\/td>\n<\/tr>\n<tr>\n<td>D\u00e2y n\u1ed1i<\/td>\n<td>\u0110\u1ec3 k\u1ebft n\u1ed1i c\u00e1c linh ki\u1ec7n.<\/td>\n<\/tr>\n<tr>\n<td>Breadboard (t\u00f9y ch\u1ecdn)<\/td>\n<td>\u0110\u1ec3 l\u1eafp r\u00e1p m\u1ea1ch d\u1ec5 d\u00e0ng.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>S\u01a1 \u0111\u1ed3 m\u1ea1ch<\/h3>\n<p>K\u1ebft n\u1ed1i c\u00e1c linh ki\u1ec7n theo s\u01a1 \u0111\u1ed3 sau:<\/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<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>VCC<\/td>\n<td>5V<\/td>\n<\/tr>\n<tr>\n<td>GND<\/td>\n<td>GND<\/td>\n<\/tr>\n<tr>\n<td>Trig<\/td>\n<td>Ch\u00e2n s\u1ed1 7 (c\u00f3 th\u1ec3 thay \u0111\u1ed5i)<\/td>\n<\/tr>\n<tr>\n<td>Echo<\/td>\n<td>Ch\u00e2n s\u1ed1 8 (c\u00f3 th\u1ec3 thay \u0111\u1ed5i)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>L\u01b0u \u00fd s\u1eed d\u1ee5ng \u0111i\u1ec7n tr\u1edf ph\u00f9 h\u1ee3p cho ch\u00e2n Trig v\u00e0 Echo n\u1ebfu c\u1ea7n.<\/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 c\u1ea3m bi\u1ebfn v\u00e0 x\u1eed l\u00fd t\u00edn hi\u1ec7u.  \u0110o\u1ea1n code m\u1eabu (s\u1eed d\u1ee5ng Arduino IDE) s\u1ebd nh\u01b0 sau:<\/p>\n<pre><code class=\"language-c++\">const int trigPin = 7;\nconst int echoPin = 8;\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 * 0.034 \/ 2;\n  Serial.print(\"Khoang cach: \");\n  Serial.print(distance);\n  Serial.println(\" cm\");\n  delay(100);\n}<\/code><\/pre>\n<p>\u0110o\u1ea1n code n\u00e0y s\u1ebd g\u1eedi m\u1ed9t xung si\u00eau \u00e2m t\u1eeb ch\u00e2n Trig v\u00e0 \u0111o th\u1eddi gian  t\u00edn hi\u1ec7u HIGH tr\u00ean ch\u00e2n Echo. T\u1eeb \u0111\u00f3, t\u00ednh to\u00e1n kho\u1ea3ng c\u00e1ch \u0111\u1ebfn v\u1eadt th\u1ec3 v\u00e0 hi\u1ec3n th\u1ecb tr\u00ean Serial Monitor.<\/p>\n<h3>Ki\u1ec3m tra v\u00e0 hi\u1ec7u ch\u1ec9nh<\/h3>\n<p>Sau khi ho\u00e0n t\u1ea5t vi\u1ec7c l\u1eafp r\u00e1p v\u00e0 l\u1eadp tr\u00ecnh, b\u1ea1n c\u1ea7n ki\u1ec3m tra ho\u1ea1t \u0111\u1ed9ng c\u1ee7a c\u1ea3m bi\u1ebfn.  \u0110\u1eb7t m\u1ed9t v\u1eadt th\u1ec3 tr\u01b0\u1edbc c\u1ea3m bi\u1ebfn v\u00e0 quan s\u00e1t gi\u00e1 tr\u1ecb kho\u1ea3ng c\u00e1ch hi\u1ec3n th\u1ecb tr\u00ean Serial Monitor.  N\u1ebfu c\u1ea7n, hi\u1ec7u ch\u1ec9nh l\u1ea1i code ho\u1eb7c m\u1ea1ch \u0111i\u1ec7n \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 ch\u00ednh x\u00e1c.<\/p>\n<p>Vi\u1ec7c t\u1ef1 ch\u1ebf t\u1ea1o c\u1ea3m bi\u1ebfn si\u00eau \u00e2m kh\u00f4ng ch\u1ec9 gi\u00fap b\u1ea1n ti\u1ebft ki\u1ec7m chi ph\u00ed m\u00e0 c\u00f2n mang l\u1ea1i s\u1ef1 hi\u1ec3u bi\u1ebft s\u00e2u s\u1eafc v\u1ec1 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a thi\u1ebft b\u1ecb n\u00e0y.  Hy v\u1ecdng b\u00e0i vi\u1ebft n\u00e0y \u0111\u00e3 cung c\u1ea5p cho b\u1ea1n nh\u1eefng th\u00f4ng tin c\u1ea7n thi\u1ebft \u0111\u1ec3 b\u1eaft \u0111\u1ea7u.  Tuy nhi\u00ean, c\u1ea7n l\u01b0u \u00fd r\u1eb1ng vi\u1ec7c t\u1ef1 ch\u1ebf t\u1ea1o c\u00f3 th\u1ec3 g\u1eb7p m\u1ed9t s\u1ed1 kh\u00f3 kh\u0103n v\u1ec1 \u0111\u1ed9 ch\u00ednh x\u00e1c v\u00e0 \u1ed5n \u0111\u1ecbnh.  N\u1ebfu y\u00eau c\u1ea7u \u0111\u1ed9 ch\u00ednh x\u00e1c cao, n\u00ean s\u1eed d\u1ee5ng c\u00e1c c\u1ea3m bi\u1ebfn si\u00eau \u00e2m ch\u1ea5t l\u01b0\u1ee3ng cao c\u00f3 s\u1eb5n tr\u00ean th\u1ecb tr\u01b0\u1eddng.<\/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 \u1edf t\u1ea7n s\u1ed1 cao h\u01a1n ng\u01b0\u1ee1ng nghe c\u1ee7a con ng\u01b0\u1eddi \u0111\u1ec3 \u0111o kho\u1ea3ng c\u00e1ch \u0111\u1ebfn m\u1ed9t v\u1eadt th\u1ec3. Vi\u1ec7c t\u1ef1 ch\u1ebf t\u1ea1o m\u1ed9t c\u1ea3m bi\u1ebfn si\u00eau \u00e2m \u0111\u00f2i h\u1ecfi ki\u1ebfn th\u1ee9c v\u1ec1 \u0111i\u1ec7n t\u1eed v\u00e0 m\u1ed9t ch\u00fat kh\u00e9o l\u00e9o, nh\u01b0ng ho\u00e0n<\/p>\n","protected":false},"author":1,"featured_media":26465,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6406],"tags":[],"class_list":["post-45212","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\/45212","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=45212"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/45212\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media\/26465"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media?parent=45212"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/categories?post=45212"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/tags?post=45212"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}