指南针
| Language | English |
|---|
目的本教程将教大家如何用Microduino-10DOF模块测到的磁场强度数据在Processing中显示一个指南针。 设备
原理图直接使用Microduino-10DOF上的HMC5883L磁场强度传感器 程序调试步骤一：按着原理图搭建硬件环境，像这样： 下载这个HMC5883L的库函数：https://github.com/manifestinteractive/arduino/tree/master/Libraries/HMC5883L 步骤二：解释一下代码： 本例需要两端的代码，Processing端和Microduino端 Microduino: 在setup()中主要是初始化HMC5883L 在loop()中计算出周围磁感应的角度 //Output()用来输出计算出的角度到串口 // Output the data down the serial port.
void Output(int RoundDegreeInt)
{
//Serial.println();
Serial.println(RoundDegreeInt);
delay(150);
}
Processing: //得到第一个串口的数据. myPort = new Serial(this, Serial.list()[0], 9600); //在draw()函数中，第一步得到串口传来的数据 while (myPort.available() > 0) {
myString = myPort.readStringUntil(lf);
if (myString != null) {
//print(myString); // Prints String
angle=float(myString); // Converts and prints float
println(angle);
}
}
translate(160, 50);
//绘制指南针的背景 // draw the compass background ellipseMode(CENTER); fill(50); stroke(10); strokeWeight(2); ellipse(150,150,300,300);
// draw the lines and dots
translate(150,150); // translate the lines and dots to the middle of the compass
float CompassX = -angle;
rotate(radians(CompassX));
noStroke();
fill(51, 255, 51);
int radius = 120;
for( int degC = 5; degC < 360; degC += 10) //Compass dots
{
float angleC = radians(degC);
float xC = 0 + (cos(angleC)* radius);
float yC = 0 + (sin(angleC)* radius);
ellipse(xC,yC, 3, 3);
}
for( int degL = 10; degL < 370; degL += 10) //Compass lines
{
float angleL = radians(degL);
float x = 0 + (cos(angleL)* 145);
float y = 0 + (sin(angleL)* 145);
if( degL==90 || degL==180 || degL==270 || degL==360) {
stroke(51, 255, 51);
strokeWeight(4);
}
else {
stroke(234,144,7);
strokeWeight(2);
}
line(0,0, x,y);
}
fill(102, 102, 102);
noStroke();
ellipseMode(CENTER);
ellipse(0,0, 228,228); //draw a filled circle to hide the lines in the middle
//绘制指南针的方向表示，东西南北 b = loadFont("Arial-BoldMT-48.vlw");
textAlign(CENTER);
// Draw the letters
fill(250);
textFont(b, 32);
text("N", 1, -90);
rotate(radians(90));
text("E", 0, -90);
rotate(radians(90));
text("S", 0, -90);
rotate(radians(90));
text("W", 0, -90);
rotate(radians(90));
textFont(b,40);
textAlign(CENTER);
//text((angle), 20, 20);
println(angle);
//draw the needle rotate(radians(-CompassX)); //make it stationary stroke(234,144,7); strokeWeight(3); triangle(-10, 0, 10, 0, 0, -85); fill(234,144,7); triangle(-10, 0, 10, 0, 0, 60); 步骤三：下载代码并编译通过。 步骤四：运行后，用一块磁铁改变一下磁场，看看指针是否变化。 结果屏幕上会显示一个简单的指南针，指针会随着磁场走，像这样： 视频 |
