arduino 的研究筆記

2016年4月15日星期五

馬達轉速量測V2.0

跑出來的結果如下:

PWM : 1250 spin : 1050
PWM : 1300 spin : 1194
PWM : 1350 spin : 1304
PWM : 1400 spin : 1387
PWM : 1450 spin : 1451
PWM : 1500 spin : 1503
PWM : 1550 spin : 1544
PWM : 1600 spin : 1579
PWM : 1650 spin : 1607
PWM : 1700 spin : 1634
PWM : 1750 spin : 1654
PWM : 1800 spin : 1682
PWM : 1850 spin : 1764
PWM : 1900 spin : 1763
PWM : 1950 spin : 1764

arduino 的code 如下:

我四根馬達接在 pin 6,7,8,9....

然後光電開關接在 A3 (analog pin 3....別懷疑...它也可以當digital pin 使用)

自己選一個馬達測試或是你也可以一次測四個...這樣比較快...但是 arduino 的code要改一下

=================================================================
#include <PinChangeInt.h>
#include <Servo.h>

int Pin = A3;
int val;
#define SERVO_NUM 4
Servo MOTOR[SERVO_NUM];
#define FL_MOTOR_OUT_PIN 6
#define FR_MOTOR_OUT_PIN 7
#define BL_MOTOR_OUT_PIN 8
#define BR_MOTOR_OUT_PIN 9

unsigned int total_cnt=0;
unsigned int older_cnt=0;
void setup()
{
Serial.begin(9600); //for debugging...

pinMode(Pin, INPUT);
PCintPort::attachInterrupt(Pin, calc,RISING);
total_cnt =0;
older_cnt =0;

MOTOR[0].attach(FL_MOTOR_OUT_PIN);
MOTOR[1].attach(FR_MOTOR_OUT_PIN);
MOTOR[2].attach(BL_MOTOR_OUT_PIN);
MOTOR[3].attach(BR_MOTOR_OUT_PIN);

MOTOR[0].writeMicroseconds(1000);
MOTOR[1].writeMicroseconds(1000);
MOTOR[2].writeMicroseconds(1000);
MOTOR[3].writeMicroseconds(1000);
}

void loop()
{
int i,j,k,rpm;

k=3;

// val = digitalRead(Pin);

//Serial.println(val); // debug value
for(i=1100;i<2000;i+=50)
{
for(j=0;j<4;j++)
{
MOTOR[k].writeMicroseconds(i);
delay(500);
// Serial.println(end_time);
if((total_cnt > older_cnt) & (j==3))
{
rpm = total_cnt - older_cnt;
older_cnt = total_cnt;
Serial.print("PWM : ");
Serial.print(i);
Serial.print(" spin : ");
Serial.println(rpm);
}else
older_cnt = total_cnt;
}

}
MOTOR[k].writeMicroseconds(1000);
while(1)
{}
}

void calc()
{

total_cnt++ ;

}

2016年4月13日星期三

grbl on raspberry

影片連結 https://youtu.be/xCgPsL3ycJQ

(Thanks to bobt on the Shapeoko forum for providing the basis for these steps)

Assuming you have the Raspberry Pi running in the GUI, open a command window (LXTerminal) and perform the following commands. Bob suggests a 8GB card, but this works on a 4GB fine – I started with about 40% SD card space in-use using the df command and ended up at about 60% use after I got it running. He is running the older 256MB, I am running the newer 512MB pi:

NOTE: All these steps in sequence may take close to two hours to complete due to the slow processor on the Pi.

sudo apt-get update (required for AlaMode)
sudo apt-get install xrdp
sudo apt-get install arduino (required for AlaMode) [For normal Pi, this step is optional, but good to have. NOTE: I got an error that not all items could be downloaded. I tried to repeat command by adding a --fix-missing, i.e. sudo apt-get install --fix-missing arduino but it didn't help. UPDATE: The latest download as of May 2013 doesn't have this problem]
sudo apt-get install libudev-dev
sudo apt-get install qtcreator [This step takes quite awhile to complete. Note: I got an error downloading as in a previous step. If you get an error, repeat command but add a --fix-missing, i.e. sudo apt-get install --fix-missing qtcreator, in this case the --fix-missing worked.]
sudo apt-get install git
mkdir github
cd github
git clone https://github.com/zapmaker/GrblHoming
curl http://www.shapeoko.com/wiki/images/6/6a/Coaster.txt > Coaster.nc
cd GrblHoming
qmake GcodeSenderGUIthreads.pro
make

Make sure that you have your Grbl/Arduino plugged into the pi prior to running the last command:

./GrblController

Pick /dev/tty/USB0 as your port and click Open. The status window should report the Grbl version.

If you wish, you can connect to your Raspberry Pi via RDP from a Windows PC (or Mac):

Determine the pi’s IP, open a terminal window and type ifconfig
In the Windows PC, open Remote Desktop Connection and enter the IP that is associated with eth0 (or the wifi interface, if using that).
You should see a login screen that originates from the pi. Enter pi as the user and raspberry as the password.
This is not like VNC, which means you have separate sessions for each RDP connection in. If you are not running headless, you first need to close any GrblControllers that are running, such as on the monitor connected to the pi, then in the RDP window, open LXTerminal, go to the GrblHoming folder and type ./GrblController as noted above

To update your code with the latest version, open a terminal window to the existing GrblHoming folder and perform these commands:

git pull
qmake GcodeSenderGUIthreads.pro
(optionally perform a make clean)
make

then run as usual.

How to tell if you need to make clean? Usually sub-minor build number increments (i.e. 3.3.2->3.3.3) do not require make clean. But minor revs probably will. If in doubt, make clean. Compiler errors definitely mean do a make clean.

Possible Hookup Configuration

I’m using a Belkin F5U234 hub which is rated by elinux to support powering the Raspberry Pi and also provide USB hub capability. This is evident in the picture below where the hub is connected to the pi in two places. Check out this site:

http://elinux.org/RPi_VerifiedPeripherals

51 THOUGHTS ON “1. RUNNING GRBL CONTROLLER ON RASPBERRY PI”

ref : http://zapmaker.org/raspberry-pi/running-grbl-controller-on-raspberry-pi/

2016年4月12日星期二

光電轉速計和arduino 的結合

之前在掏寶買的光電轉速計....剛好最近有量馬達的需求...就把他裝起來...

掏寶連結如下: https://world.taobao.com/item/20059648052.htm?fromSite=main&spm=a312a.7700846.0.0.OPM0NM&_u=d2bnm38caed7

架設起來的照片如下:

那個綠色的電路板就是光電轉速計.....

他其實就是三個訊號....VCC,GND,SIG

SIG會輸出類似方波的訊號.....當碼盤來到有洞的地方....會輸出 0.....來到沒有洞的地方... 會輸

出1....利用這個特性...我們就可以測試轉速.....

目前我是用arduino 來接收訊號....程式碼如下:

利用中斷的作法...當 sig 產生一個正緣的訊號...就把 total_cnt ++;

然後每隔一秒printf 出來total_cnt......

量測出來的結果如下

Back Rear motor:

PWM -> rpm

1200 -> 1790

1250 -> 2266

1300 -> 2550

1350 -> 2800

1400 -> 2970

1500 -> 3228

1550 -> 3305

1600 -> 3388

1650 -> 3442

1700 -> 3480

1800 -> 3560

1900 -> 3760

Front Rear motor :

PWM -> rpm

1200 -> 1720

1250 -> 2099

1300 -> 2400

1350 -> 2623

1400 -> 2823

1450 -> 3000

1500 -> 3080

1550 -> 3169

1600 -> 3255

1650 -> 3308

1700 -> 3350

1750 -> 3400

1800 -> 3442

1850 -> 3574

1900 -> 3636

=====================================================================

#include <PinChangeInt.h>

int Pin = 2;

int val;

unsigned int total_cnt=0;

unsigned int older_cnt=0;

void setup()

{

Serial.begin(9600); //for debugging...

pinMode(Pin, INPUT);

PCintPort::attachInterrupt(Pin, calc,RISING);

total_cnt =0;

older_cnt =0;

}

void loop()

{

// val = digitalRead(Pin);

//Serial.println(val); // debug value

delay(1000);

// Serial.println(end_time);

if(total_cnt > older_cnt)

{

Serial.println(total_cnt - older_cnt);

}

older_cnt = total_cnt;

}

void calc()

{

total_cnt++ ;

}

2016年3月24日星期四

arduino pwm frequency table

he 8-bit PWM value that you set when you call the analogWrite function:

analogWrite(myPWMpin, value); Outputs a square wave

// For Arduino Uno, Nano, Micro Magician, Mini Driver, Lilly Pad and any other board using ATmega 8, 168 or 328**
 
//---------------------------------------------- Set PWM frequency for D5 & D6 -------------------------------
 
//TCCR0B = TCCR0B & B11111000 | B00000001;    // set timer 0 divisor to     1 for PWM frequency of 62500.00 Hz
//TCCR0B = TCCR0B & B11111000 | B00000010;    // set timer 0 divisor to     8 for PWM frequency of  7812.50 Hz
  TCCR0B = TCCR0B & B11111000 | B00000011;    // set timer 0 divisor to    64 for PWM frequency of   976.56 Hz (The DEFAULT)
//TCCR0B = TCCR0B & B11111000 | B00000100;    // set timer 0 divisor to   256 for PWM frequency of   244.14 Hz
//TCCR0B = TCCR0B & B11111000 | B00000101;    // set timer 0 divisor to  1024 for PWM frequency of    61.04 Hz
 
 
//---------------------------------------------- Set PWM frequency for D9 & D10 ------------------------------
 
//TCCR1B = TCCR1B & B11111000 | B00000001;    // set timer 1 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR1B = TCCR1B & B11111000 | B00000010;    // set timer 1 divisor to     8 for PWM frequency of  3921.16 Hz
  TCCR1B = TCCR1B & B11111000 | B00000011;    // set timer 1 divisor to    64 for PWM frequency of   490.20 Hz (The DEFAULT)
//TCCR1B = TCCR1B & B11111000 | B00000100;    // set timer 1 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR1B = TCCR1B & B11111000 | B00000101;    // set timer 1 divisor to  1024 for PWM frequency of    30.64 Hz
 
//---------------------------------------------- Set PWM frequency for D3 & D11 ------------------------------
 
//TCCR2B = TCCR2B & B11111000 | B00000001;    // set timer 2 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR2B = TCCR2B & B11111000 | B00000010;    // set timer 2 divisor to     8 for PWM frequency of  3921.16 Hz
//TCCR2B = TCCR2B & B11111000 | B00000011;    // set timer 2 divisor to    32 for PWM frequency of   980.39 Hz
  TCCR2B = TCCR2B & B11111000 | B00000100;    // set timer 2 divisor to    64 for PWM frequency of   490.20 Hz (The DEFAULT)
//TCCR2B = TCCR2B & B11111000 | B00000101;    // set timer 2 divisor to   128 for PWM frequency of   245.10 Hz
//TCCR2B = TCCR2B & B11111000 | B00000110;    // set timer 2 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR2B = TCCR2B & B11111000 | B00000111;    // set timer 2 divisor to  1024 for PWM frequency of    30.64 Hz
 
 
 
//For Arduino Mega1280, Mega2560, MegaADK, Spider or any other board using ATmega1280 or ATmega2560**
 
//---------------------------------------------- Set PWM frequency for D4 & D13 ------------------------------
 
//TCCR0B = TCCR0B & B11111000 | B00000001;    // set timer 0 divisor to     1 for PWM frequency of 62500.00 Hz
//TCCR0B = TCCR0B & B11111000 | B00000010;    // set timer 0 divisor to     8 for PWM frequency of  7812.50 Hz
  TCCR0B = TCCR0B & B11111000 | B00000011;    <// set timer 0 divisor to    64 for PWM frequency of   976.56 Hz (Default)
//TCCR0B = TCCR0B & B11111000 | B00000100;    // set timer 0 divisor to   256 for PWM frequency of   244.14 Hz
//TCCR0B = TCCR0B & B11111000 | B00000101;    // set timer 0 divisor to  1024 for PWM frequency of    61.04 Hz
 
 
//---------------------------------------------- Set PWM frequency for D11 & D12 -----------------------------
 
//TCCR1B = TCCR1B & B11111000 | B00000001;    // set timer 1 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR1B = TCCR1B & B11111000 | B00000010;    // set timer 1 divisor to     8 for PWM frequency of  3921.16 Hz
  TCCR1B = TCCR1B & B11111000 | B00000011;    // set timer 1 divisor to    64 for PWM frequency of   490.20 Hz
//TCCR1B = TCCR1B & B11111000 | B00000100;    // set timer 1 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR1B = TCCR1B & B11111000 | B00000101;    // set timer 1 divisor to  1024 for PWM frequency of    30.64 Hz
 
//---------------------------------------------- Set PWM frequency for D9 & D10 ------------------------------
 
//TCCR2B = TCCR2B & B11111000 | B00000001;    // set timer 2 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR2B = TCCR2B & B11111000 | B00000010;    // set timer 2 divisor to     8 for PWM frequency of  3921.16 Hz
//TCCR2B = TCCR2B & B11111000 | B00000011;    // set timer 2 divisor to    32 for PWM frequency of   980.39 Hz
  TCCR2B = TCCR2B & B11111000 | B00000100;    // set timer 2 divisor to    64 for PWM frequency of   490.20 Hz
//TCCR2B = TCCR2B & B11111000 | B00000101;    // set timer 2 divisor to   128 for PWM frequency of   245.10 Hz
//TCCR2B = TCCR2B & B11111000 | B00000110;    // set timer 2 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR2B = TCCR2B & B11111000 | B00000111;    // set timer 2 divisor to  1024 for PWM frequency of    30.64 Hz
 
 
//---------------------------------------------- Set PWM frequency for D2, D3 & D5 ---------------------------
 
//TCCR3B = TCCR3B & B11111000 | B00000001;    // set timer 3 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR3B = TCCR3B & B11111000 | B00000010;    // set timer 3 divisor to     8 for PWM frequency of  3921.16 Hz
  TCCR3B = TCCR3B & B11111000 | B00000011;    // set timer 3 divisor to    64 for PWM frequency of   490.20 Hz
//TCCR3B = TCCR3B & B11111000 | B00000100;    // set timer 3 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR3B = TCCR3B & B11111000 | B00000101;    // set timer 3 divisor to  1024 for PWM frequency of    30.64 Hz
 
 
//---------------------------------------------- Set PWM frequency for D6, D7 & D8 ---------------------------
 
//TCCR4B = TCCR4B & B11111000 | B00000001;    // set timer 4 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR4B = TCCR4B & B11111000 | B00000010;    // set timer 4 divisor to     8 for PWM frequency of  3921.16 Hz
  TCCR4B = TCCR4B & B11111000 | B00000011;    // set timer 4 divisor to    64 for PWM frequency of   490.20 Hz
//TCCR4B = TCCR4B & B11111000 | B00000100;    // set timer 4 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR4B = TCCR4B & B11111000 | B00000101;    // set timer 4 divisor to  1024 for PWM frequency of    30.64 Hz
 
 
//---------------------------------------------- Set PWM frequency for D44, D45 & D46 ------------------------
 
//TCCR5B = TCCR5B & B11111000 | B00000001;    // set timer 5 divisor to     1 for PWM frequency of 31372.55 Hz
//TCCR5B = TCCR5B & B11111000 | B00000010;    // set timer 5 divisor to     8 for PWM frequency of  3921.16 Hz
  TCCR5B = TCCR5B & B11111000 | B00000011;    // set timer 5 divisor to    64 for PWM frequency of   490.20 Hz
//TCCR5B = TCCR5B & B11111000 | B00000100;    // set timer 5 divisor to   256 for PWM frequency of   122.55 Hz
//TCCR5B = TCCR5B & B11111000 | B00000101;    // set timer 5 divisor to  1024 for PWM frequency of    30.64 Hz

Reference : https://arduino-info.wikispaces.com/Arduino-PWM-Frequency

2016年3月18日星期五

SG-90 馬達和 57BYGH82

一般伺服馬達有三條線，電源（紅色）、接地（黑或棕色）、訊號線（白、黃、橘、藍，甚至是黑色）。透過訊號線傳送PWM脈波來控制軸柄的停止位置旋轉角度，這個訊號脈波必須每秒重複50次（也就是50Hz），而脈衝持續時間長短便代表了馬達該將軸柄轉到什麼位置，範圍從1.0ms到2.0ms（millisecond，毫秒，千分之一秒），若想置中則是1.5ms；也可將1.0ms當做角度0度，那麼1.5ms會是90度，2.0ms則是轉到底180度。注意，也有可能反過來。

不過每個廠牌型號的伺服馬達可允許旋轉的角度各不相同，也就是說可接受的訊號脈衝範圍也不相同，必須查閱產品資料規格書，若超出範圍可能會損害伺服馬達。底下是Tower Pro SG90的規格：

重量：9g
尺寸：23*12.2*29mm
工作電壓：4.8V
轉矩：1.8kg-cm，當工作電壓為4.8V時
運轉速度：0.1秒 ∕ 60度，當工作電壓為4.8V時
脈衝寬度範圍：500~2400µs
死頻帶寬度（dead band width）：10µs

從中我們可知，可允許的脈衝範圍是500~2400µs，也就是0.5~2.4ms，比剛剛說的一般範圍還要寬，也就代表這個伺服馬達能旋轉的角度更大。另外有項值得一提的數據是死頻帶寬度，意思是說，因為訊號可能不穩上下起伏，當這一次脈衝寬度與上一次相差不超過死頻帶寬度時，伺服馬達便不會動作。

硬體線路很簡單，因為只有一個伺服馬達，我直接由Arduino的5V腳位供電。若想使用超過兩個，則應以另外的電源供電，而且要記得共同接地。

電路圖如下，除了電源5V與接地外，訊號線接往Arduino的數位腳位9。

照片如下，Tower Pro SG90的三條線顏色分別是黃、紅、棕，對應訊號、電源、接地。

接下來是軟體的部份，先讓伺服馬達來回旋轉吧。

#include <Servo.h>

Servo myservo; // 建立Servo物件，控制伺服馬達

void setup()
{
  myservo.attach(9, 500, 2400); // 修正脈衝寬度範圍
}

void loop()
{
for(int i = 500; i <= 2400; i+=100){
    myservo.writeMicroseconds(i); // 直接以脈衝寬度控制

    delay(300);
}
for(int i = 2400; i >= 500; i-=100){
    myservo.writeMicroseconds(i);

    delay(300);
}
}