{"id":579,"date":"2014-08-25T16:00:08","date_gmt":"2014-08-25T15:00:08","guid":{"rendered":"http:\/\/ofalcao.pt\/blog\/?p=579"},"modified":"2014-08-25T16:00:08","modified_gmt":"2014-08-25T15:00:08","slug":"ad4m4st0r-medindo-luminosidade","status":"publish","type":"post","link":"https:\/\/ofalcao.pt\/blog\/2014\/ad4m4st0r-medindo-luminosidade","title":{"rendered":"AD4M4ST0R &#8211; medindo luminosidade"},"content":{"rendered":"<div class=\"seriesmeta\">This post is part 6 of 9 of \u00a0<a href=\"https:\/\/ofalcao.pt\/blog\/series\/ad4m4st0r-um-rover-lego\" class=\"series-122\" title=\"AD4M4ST0R - um rover LEGO\">AD4M4ST0R - um rover LEGO<\/a><\/div><p>A ideia \u00e9 utilizar um sensor de cor para medir a luminosidade de modo a acender os LEDs de ilumina\u00e7\u00e3o apenas o necess\u00e1rio para garantir uma imagem razo\u00e1vel.<\/p>\n<p>O sensor utilizado \u00e9 um <a href=\"http:\/\/education.lego.com\/da-dk\/lego-education-product-database\/mindstorms-ev3\/45506-color-sensor\">EV3 Color Sensor (45506)<\/a>. Na wiki do projecto ev3dev h\u00e1 2 artigos com a informa\u00e7\u00e3o suficiente:<\/p>\n<ul>\n<li><a href=\"https:\/\/github.com\/ev3dev\/ev3dev\/wiki\/Using-Sensors\">Using Sensors<\/a><\/li>\n<li><a href=\"https:\/\/github.com\/ev3dev\/ev3dev\/wiki\/LEGO-EV3-Color-Sensor-(45506)\">LEGO EV3 Color Sensor (45506)<\/a><\/li>\n<\/ul>\n<p>Ap\u00f3s a liga\u00e7\u00e3o o sensor \u00e9 imediatamente reconhecido:<\/p>\n<pre>root@ev3dev:~# dmesg\n(...)\nev3-uart-host in2:ev3-uart-host: Started.\nRegistered LEGOEV3 line discipline. (29)\nmsensor sensor0: Mindstorms sensor registered.<\/pre>\n<p>Sendo o \u00fanico sensor ligado aparece referenciado como &#8216;sensor0&#8217; debaixo da classe &#8216;msensor&#8217;:<\/p>\n<pre>root@ev3dev:~# ls \/sys\/class\/msensor\/ -la\nlrwxrwxrwx\u00a0 1 root root 0 Aug 24 00:46 sensor0 -&gt; ..\/..\/devices\/platform\/serial8250.0\/tty\/ttyS0\/ttyS0:ev3-uart-sensor\/msensor\/sensor0<\/pre>\n<p>Temos a seguinte informa\u00e7\u00e3o dispon\u00edvel:<\/p>\n<pre>root@ev3dev:~# ls \/sys\/class\/msensor\/sensor0\nbin_data\u00a0\u00a0 \u00a0 device\u00a0 mode\u00a0\u00a0 \u00a0num_values\u00a0 power\u00a0\u00a0\u00a0\u00a0\u00a0 type_id\u00a0\u00a0 \u00a0units\u00a0\u00a0 \u00a0value1\u00a0\u00a0 \u00a0value3\u00a0\u00a0 \u00a0value5\u00a0\u00a0 \u00a0value7\nbin_data_format\u00a0 dp\u00a0\u00a0 \u00a0 modes\u00a0\u00a0 \u00a0port_name\u00a0\u00a0 subsystem\u00a0 uevent\u00a0\u00a0 \u00a0value0\u00a0\u00a0 \u00a0value2\u00a0\u00a0 \u00a0value4\u00a0\u00a0 \u00a0value6<\/pre>\n<p>O sensor \u00e9 inicializado no modo &#8216;COL-REFLECT&#8217; mas podemos mudar para um dos seguintes modos dispon\u00edveis:<\/p>\n<pre>root@ev3dev:~# cat \/sys\/class\/msensor\/sensor0\/mode\nCOL-REFLECT\n\nroot@ev3dev:~# cat \/sys\/class\/msensor\/sensor0\/modes\nCOL-REFLECT COL-AMBIENT COL-COLOR REF-RAW RGB-RAW COL-CAL<\/pre>\n<p>Pretendo operar no modo &#8216;COL-AMBIENT&#8217;:<\/p>\n<pre>root@ev3dev:~# echo COL-AMBIENT &gt; \/sys\/class\/msensor\/sensor0\/mode<\/pre>\n<p>Neste modo o sensor gera apenas um valor:<\/p>\n<pre>root@ev3dev:~# cat \/sys\/class\/msensor\/sensor0\/num_values\n1<\/pre>\n<p>que ser\u00e1 portanto &#8216;value0&#8217;:<\/p>\n<pre>root@ev3dev:~# cat \/sys\/class\/msensor\/sensor0\/value0\n3\n\n<\/pre>\n<p>Infelizmente a gama de valores lida pelo sensor deixa muito a desejar: no mesmo local na minha sala observei de &#8216;1&#8217; (de noite com luz fraca) a &#8217;17&#8217; (numa tarde t\u00edpica de Agosto sendo a sala virada a Sul embora n\u00e3o haja incid\u00eancia directa no sensor). E com uma lanterna a apontar directamente ao sensor obtenho &#8217;68&#8217;.<\/p>\n<p>Tirei algumas fotos com v\u00e1rios valores de leitura e v\u00e1rios duty cycles aplicados a 3 pares de LEDs Power Functions para tentar elaborar uma regra (o rover e a minifig sempre no mesmo local com cerca de 15 cm entre a webcam e a minifig, a ilumina\u00e7\u00e3o dos LEDs nunca alterou o valor medido pelo sensor e todas as fotos foram apenas reduzidas dos 640&#215;480 originais para 160&#215;120)<\/p>\n<table>\n<tbody>\n<tr>\n<th>Brightness<\/th>\n<th style=\"text-align: center;\" colspan=\"7\">Duty Cycle<\/th>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">(%)<\/td>\n<td style=\"text-align: center;\">0%<\/td>\n<td style=\"text-align: center;\">25%<\/td>\n<td style=\"text-align: center;\">33%<\/td>\n<td style=\"text-align: center;\">50%<\/td>\n<td style=\"text-align: center;\">66%<\/td>\n<td style=\"text-align: center;\">75%<\/td>\n<td style=\"text-align: center;\">100%<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">1<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright01-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-580\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright01-duty000.jpg?resize=80%2C60\" alt=\"bright01-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright01-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-581\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright01-duty100.jpg?resize=80%2C60\" alt=\"bright01-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">3<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-582\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty000.jpg?resize=80%2C60\" alt=\"bright03-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty025.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-583\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty025.jpg?resize=80%2C60\" alt=\"bright03-duty025\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty033.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-584\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty033.jpg?resize=80%2C60\" alt=\"bright03-duty033\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty050.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-585\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty050.jpg?resize=80%2C60\" alt=\"bright03-duty050\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-586\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty066.jpg?resize=80%2C60\" alt=\"bright03-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty075.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-587\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty075.jpg?resize=80%2C60\" alt=\"bright03-duty075\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-588\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright03-duty100.jpg?resize=80%2C60\" alt=\"bright03-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">4<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-591\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty000.jpg?resize=80%2C60\" alt=\"bright04-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty025.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-592\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty025.jpg?resize=80%2C60\" alt=\"bright04-duty025\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty033.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-593\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty033.jpg?resize=80%2C60\" alt=\"bright04-duty033\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty050.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-594\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty050.jpg?resize=80%2C60\" alt=\"bright04-duty050\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-595\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty066.jpg?resize=80%2C60\" alt=\"bright04-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty075.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-596\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty075.jpg?resize=80%2C60\" alt=\"bright04-duty075\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-597\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright04-duty100.jpg?resize=80%2C60\" alt=\"bright04-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">5<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-599\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty000.jpg?resize=80%2C60\" alt=\"bright05-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty025.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-600\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty025.jpg?resize=80%2C60\" alt=\"bright05-duty025\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty033.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-601\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty033.jpg?resize=80%2C60\" alt=\"bright05-duty033\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty050.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-602\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty050.jpg?resize=80%2C60\" alt=\"bright05-duty050\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-603\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty066.jpg?resize=80%2C60\" alt=\"bright05-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty075.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-604\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty075.jpg?resize=80%2C60\" alt=\"bright05-duty075\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-605\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright05-duty100.jpg?resize=80%2C60\" alt=\"bright05-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">6<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-612\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty000.jpg?resize=80%2C60\" alt=\"bright06-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty025.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-613\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty025.jpg?resize=80%2C60\" alt=\"bright06-duty025\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty033.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-614\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty033.jpg?resize=80%2C60\" alt=\"bright06-duty033\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty050.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-615\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty050.jpg?resize=80%2C60\" alt=\"bright06-duty050\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-616\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty066.jpg?resize=80%2C60\" alt=\"bright06-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty075.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-617\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty075.jpg?resize=80%2C60\" alt=\"bright06-duty075\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-618\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright06-duty100.jpg?resize=80%2C60\" alt=\"bright06-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">13<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-627\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty000.jpg?resize=80%2C60\" alt=\"bright13-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty033.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-628\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty033.jpg?resize=80%2C60\" alt=\"bright13-duty033\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-629\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty066.jpg?resize=80%2C60\" alt=\"bright13-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-630\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright13-duty100.jpg?resize=80%2C60\" alt=\"bright13-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">17<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty000.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-622\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty000.jpg?resize=80%2C60\" alt=\"bright17-duty000\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty066.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-623\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty066.jpg?resize=80%2C60\" alt=\"bright17-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty0661.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-624\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty0661.jpg?resize=80%2C60\" alt=\"bright17-duty066\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<td style=\"text-align: center;\">&#8211;<\/td>\n<td><a href=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty100.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-625\" src=\"https:\/\/i0.wp.com\/151.236.52.166\/blog\/wp-content\/uploads\/2014\/08\/bright17-duty100.jpg?resize=80%2C60\" alt=\"bright17-duty100\" width=\"80\" height=\"60\" \/><\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>&nbsp;<\/p>\n<p>Com esta informa\u00e7\u00e3o optei pela seguinte fun\u00e7\u00e3o &#8216;fuzzy logic&#8217;:<\/p>\n<ul>\n<li>Brightness\u00a0&lt;6\u00a0 =&gt; Duty Cycle = 100%<\/li>\n<li>Brightness\u00a0\u2208[6, 7]\u00a0=&gt; Duty Cycle = 75%<\/li>\n<li>Brightness \u2208[8, 9]\u00a0=&gt; Duty Cycle = 66%<\/li>\n<li>Brightness \u2208[10,11] =&gt; Duty Cycle = 50%<\/li>\n<li>Brightness \u2208[12,13]\u00a0=&gt; Duty Cycle = 33%<\/li>\n<li>Brightness &gt;13 =&gt; Duty Cycle = 0%<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<div class=\"seriesmeta\">This post is part 6  of 9 of \u00a0<a href=\"https:\/\/ofalcao.pt\/blog\/series\/ad4m4st0r-um-rover-lego\" class=\"series-122\" title=\"AD4M4ST0R - um rover LEGO\">AD4M4ST0R - um rover LEGO<\/a><\/div><p>A ideia \u00e9 utilizar um sensor de cor para medir a luminosidade de modo a acender os LEDs de ilumina\u00e7\u00e3o apenas o necess\u00e1rio para garantir uma imagem razo\u00e1vel. O sensor utilizado \u00e9 um EV3 Color Sensor (45506). Na wiki do projecto ev3dev h\u00e1 2 artigos com a informa\u00e7\u00e3o suficiente: Using Sensors LEGO EV3 Color Sensor &hellip; <a href=\"https:\/\/ofalcao.pt\/blog\/2014\/ad4m4st0r-medindo-luminosidade\" class=\"more-link\">Continuar a ler<span class=\"screen-reader-text\"> &#8220;AD4M4ST0R &#8211; medindo luminosidade&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","enabled":false},"version":2}},"categories":[13,18,19,20],"tags":[41,46],"series":[122],"class_list":["post-579","post","type-post","status-publish","format-standard","hentry","category-ev3dev","category-lego","category-lego-mindstorms","category-linux","tag-brightness","tag-color-sensor","series-ad4m4st0r-um-rover-lego"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2Mhyv-9l","_links":{"self":[{"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/posts\/579","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/comments?post=579"}],"version-history":[{"count":0,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/posts\/579\/revisions"}],"wp:attachment":[{"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/media?parent=579"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/categories?post=579"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/tags?post=579"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/ofalcao.pt\/blog\/wp-json\/wp\/v2\/series?post=579"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}