Blog

You are currently viewing python code for Robot Arm Controller Using arduino
Python Code For Robot Arm Controller Using Arduino

python code for Robot Arm Controller Using arduino

Spread the love

 Introduction :

In  this article we are going to implement straightforward Arduino robot controller using python code. so let’s get started :

Python Code For Robot Arm Controller Using Arduino
Python Code For Robot Arm Controller Using Arduino

Pre- requirement :

  • Wireless Xbox 360 dongle
  • Xbox 360 controller
  • Raspberry Pi
  • Arduino
  • Robot arm kit

Pin connection board (Python Code For Robot Arm Controller Using Arduino)

Step 1 :

First make the pin connection of servo motor to arduino uno

Step 2:

Then connect Arduino to the Raspberry Pi through USB along with the wireless Xbox 360 dongle.

Step 3: Installation 

You need to confirm to see all installation file are loaded successfully or not. i.e. Installed servo motor arduino library 

Next is to setup arduino-python3 environment. and install pyserial 2.6 using this:

So let’s install pyserial using this:

pip install pyserial

(Note: If you are face any library installation problem then please see our previous post )

Arduino code for Robot Arm Controller Using Arduino project :

#!/usr/bin/env python
from __future__ import print_function
import xbox
from Arduino import Arduino
import time

# Define Arduino variables
servo1 = 9
servo2 = 6
servo3 = 5
servo4 = 3
servo5 = 11

board = Arduino()
board.Servos.attach(servo1)
board.Servos.attach(servo2)
board.Servos.attach(servo3)
board.Servos.attach(servo4)
board.Servos.attach(servo5)

angle1 = 90
angle2 = 90
angle3 = 90
angle4 = 90
angle5 = 0

# Format floating point number to string format -x.xxx
def fmtFloat(n):
    return '{:6.3f}'.format(n)

# Print one or more values without a line feed
def show(*args):
    for arg in args:
        print(arg, end="")

# Print true or false value based on a boolean, without linefeed
def showIf(boolean, ifTrue, ifFalse=" "):
    if boolean:
        show(ifTrue)
    else:
        show(ifFalse)

# Move servo with respect to the left analog stick X values limited to the min-max angle set 
def leftXmove(servonum,minAngle,maxAngle):
    angle = angle1
    if int(joy.leftX()) > 0:
        angle = angle - 2 
        if angle <= minAngle:
            angle = minAngle
        return angle
    elif int(joy.leftX()) < 0:
        angle = angle + 2
        if angle >= maxAngle:
            angle = maxAngle
        return angle
    else:
        return angle
    
# Move servo with respect to the left analog stick X values limited to the min-max angle set 
def leftYmove(servonum,minAngle,maxAngle):
    angle = angle2
    if int(joy.leftY()) > 0:
        angle = angle - 2
        if angle <= minAngle:
            angle = minAngle
        return angle
    elif int(joy.leftY()) < 0:
        angle = angle + 2
        if angle >- maxAngle:
            angle = maxAngle
        return angle
    else:
        return angle

# Move servo with respect to the right analog stick Y values limited to the min-max angle set     
def rightYmove(servonum,minAngle,maxAngle):
    angle = angle3
    if int(joy.rightY()) > 0:
        angle = angle - 2
        if angle <= minAngle:
            angle = minAngle
        return angle
    elif int(joy.rightY()) < 0:
        angle = angle + 2
        if angle >= maxAngle:
            angle = maxAngle
        return angle
    else:
        return angle

	
# Move servo with respect to the right analog stick X values limited to the min-max angle set     
def rightXmove(servonum,minAngle,maxAngle):
    angle = angle4
    if int(joy.rightX()) > 0:
        angle = angle - 2
        if angle <= minAngle:
            angle = minAngle
        return angle
    elif int(joy.rightX()) < 0:
        angle = angle + 2
        if angle >= maxAngle:
            angle = maxAngle
        return angle
    else:
        return angle

# Move servo when right trigger is used
def rightTrigmove(servonum,minAngle,maxAngle):
    angle5 = minAngle
    if int(joy.rightTrigger()) > 0:
        angle5 = maxAngle
        board.Servos.write(servonum,angle5)
    else:
        board.Servos.write(servonum,minAngle)

# Instantiate the controller
joy = xbox.Joystick()

# Show various axis and button states until Back button is pressed
print("Xbox controller sample: Press Back button to exit")
while not joy.Back():
    # Show connection status
    show("Connected:")
    showIf(joy.connected(), "Y", "N")    
    # Left analog stick
    show("  Left X/Y:", fmtFloat(joy.leftX()), "/", fmtFloat(joy.leftY()))      
    # Right analog stick
    show("  Right X/Y:", fmtFloat(joy.rightX()), "/", fmtFloat(joy.rightY()))  
    # Right trigger
    show("  RightTrg:", fmtFloat(joy.rightTrigger()))
    # Poll controller leftX values and move servo1 accordingly
    angle1 = leftXmove(servo1,0,180)
    board.Servos.write(servo1,angle1)
    # Poll controller leftY values and move servo2 accordingly
    angle2 = leftYmove(servo2,0,120)
    board.Servos.write(servo2,angle2)
    # Poll controller rightY values and move servo3 accordingly
    angle3 = rightYmove(servo3,0,180)
    board.Servos.write(servo3,angle3)
    # Poll controller rightX values and move servo4 accordingly
    angle4 = rightXmove(servo4,0,180)
    board.Servos.write(servo4,angle4)
    # Move claw conencted to servo5 depending on right trigger value
    rightTrigmove(servo5,0,90)
    # A/B/X/Y buttons
    show("  Buttons:")
    showIf(joy.A(), "A")
    showIf(joy.B(), "B")
    showIf(joy.X(), "X")
    showIf(joy.Y(), "Y") 
    # Dpad U/D/L/R
    show("  Dpad:")
    showIf(joy.dpadUp(),    "U")
    showIf(joy.dpadDown(),  "D")
    showIf(joy.dpadLeft(),  "L")
    showIf(joy.dpadRight(), "R")  
    # Move cursor back to start of line
    show(chr(13))
# Close out when done
joy.close()

Arduino prototype code :

#include <SoftwareSerial.h>
#include <Wire.h>
#include <Servo.h>
#include <EEPROM.h>

void Version(){
  Serial.println(F("V0.6"));
}


SoftwareSerial *sserial = NULL;
Servo servos[8];
int servo_pins[] = {0, 0, 0, 0, 0, 0, 0, 0};
boolean connected = false;

int Str2int (String Str_value)
{
  char buffer[10]; //max length is three units
  Str_value.toCharArray(buffer, 10);
  int int_value = atoi(buffer);
  return int_value;
}

void split(String results[], int len, String input, char spChar) {
  String temp = input;
  for (int i=0; i<len; i++) {
    int idx = temp.indexOf(spChar);
    results[i] = temp.substring(0,idx);
    temp = temp.substring(idx+1);
  }
}

uint8_t readCapacitivePin(String data) {
  int pinToMeasure = Str2int(data);
  // readCapacitivePin
  //  Input: Arduino pin number
  //  Output: A number, from 0 to 17 expressing
  //  how much capacitance is on the pin
  //  When you touch the pin, or whatever you have
  //  attached to it, the number will get higher
  //  http://playground.arduino.cc/Code/CapacitiveSensor
  //
  // Variables used to translate from Arduino to AVR pin naming
  volatile uint8_t* port;
  volatile uint8_t* ddr;
  volatile uint8_t* pin;
  // Here we translate the input pin number from
  //  Arduino pin number to the AVR PORT, PIN, DDR,
  //  and which bit of those registers we care about.
  byte bitmask;
  port = portOutputRegister(digitalPinToPort(pinToMeasure));
  ddr = portModeRegister(digitalPinToPort(pinToMeasure));
  bitmask = digitalPinToBitMask(pinToMeasure);
  pin = portInputRegister(digitalPinToPort(pinToMeasure));
  // Discharge the pin first by setting it low and output
  *port &= ~(bitmask);
  *ddr  |= bitmask;
  delay(1);
  // Make the pin an input with the internal pull-up on
  *ddr &= ~(bitmask);
  *port |= bitmask;

  // Now see how long the pin to get pulled up. This manual unrolling of the loop
  // decreases the number of hardware cycles between each read of the pin,
  // thus increasing sensitivity.
  uint8_t cycles = 17;
       if (*pin & bitmask) { cycles =  0;}
  else if (*pin & bitmask) { cycles =  1;}
  else if (*pin & bitmask) { cycles =  2;}
  else if (*pin & bitmask) { cycles =  3;}
  else if (*pin & bitmask) { cycles =  4;}
  else if (*pin & bitmask) { cycles =  5;}
  else if (*pin & bitmask) { cycles =  6;}
  else if (*pin & bitmask) { cycles =  7;}
  else if (*pin & bitmask) { cycles =  8;}
  else if (*pin & bitmask) { cycles =  9;}
  else if (*pin & bitmask) { cycles = 10;}
  else if (*pin & bitmask) { cycles = 11;}
  else if (*pin & bitmask) { cycles = 12;}
  else if (*pin & bitmask) { cycles = 13;}
  else if (*pin & bitmask) { cycles = 14;}
  else if (*pin & bitmask) { cycles = 15;}
  else if (*pin & bitmask) { cycles = 16;}

  // Discharge the pin again by setting it low and output
  //  It's important to leave the pins low if you want to
  //  be able to touch more than 1 sensor at a time - if
  //  the sensor is left pulled high, when you touch
  //  two sensors, your body will transfer the charge between
  //  sensors.
  *port &= ~(bitmask);
  *ddr  |= bitmask;

  //return cycles;
  Serial.println(cycles);
}

void Tone(String data){
  int idx = data.indexOf('%');
  int len = Str2int(data.substring(0,idx));
  String data2 = data.substring(idx+1);
  int idx2 = data2.indexOf('%');
  int pin = Str2int(data2.substring(0,idx2));
  String data3 = data2.substring(idx2+1);
  String melody[len*2];
  split(melody,len*2,data3,'%');

  for (int thisNote = 0; thisNote < len; thisNote++) {
    int noteDuration = 1000/Str2int(melody[thisNote+len]);
    int note = Str2int(melody[thisNote]);
    tone(pin, note, noteDuration);
    int pause = noteDuration * 1.30;
    delay(pause);
    noTone(pin);
  }
}

void ToneNo(String data){
  int pin = Str2int(data);
  noTone(pin);
}

void DigitalHandler(int mode, String data){
      int pin = Str2int(data);
    if(mode<=0){ //read
        Serial.println(digitalRead(pin));
    }else{
        if(pin <0){
            digitalWrite(-pin,LOW);
        }else{
            digitalWrite(pin,HIGH);
        }
        //Serial.println('0');
    }
}

void AnalogHandler(int mode, String data){
     if(mode<=0){ //read
        int pin = Str2int(data);
        Serial.println(analogRead(pin));
    }else{
        String sdata[2];
        split(sdata,2,data,'%');
        int pin = Str2int(sdata[0]);
        int pv = Str2int(sdata[1]);
        analogWrite(pin,pv);
    }
}

void ConfigurePinHandler(String data){
    int pin = Str2int(data);
    if(pin <=0){
        pinMode(-pin,INPUT);
    }else{
        pinMode(pin,OUTPUT);
    }
}

void shiftOutHandler(String data) {
    String sdata[4];
    split(sdata, 4, data, '%');
    int dataPin = sdata[0].toInt();
    int clockPin = sdata[1].toInt();
    String bitOrderName = sdata[2];
    byte value = (byte)(sdata[3].toInt());
    if (bitOrderName == "MSBFIRST") {
       shiftOut(dataPin, clockPin, MSBFIRST, value);
    } else {
       shiftOut(dataPin, clockPin, LSBFIRST, value);
    }
}

void shiftInHandler(String data) {
    String sdata[3];
    split(sdata, 3, data, '%');
    int dataPin = sdata[0].toInt();
    int clockPin = sdata[1].toInt();
    String bitOrderName = sdata[2];
    int incoming;
    if (bitOrderName == "MSBFIRST") {
       incoming = (int)shiftIn(dataPin, clockPin, MSBFIRST);
    } else {
       incoming = (int)shiftIn(dataPin, clockPin, LSBFIRST);
    }
    Serial.println(incoming);
}

void SS_set(String data){
  delete sserial;
  String sdata[3];
  split(sdata,3,data,'%');
  int rx_ = Str2int(sdata[0]);
  int tx_ = Str2int(sdata[1]);
  int baud_ = Str2int(sdata[2]);
  sserial = new SoftwareSerial(rx_, tx_);
  sserial->begin(baud_);
  Serial.println("ss OK");
}

void SS_write(String data) {
 int len = data.length()+1;
 char buffer[len];
 data.toCharArray(buffer,len);
 Serial.println("ss OK");
 sserial->write(buffer);
}
void SS_read(String data) {
 char c = sserial->read();
 Serial.println(c);
}

void pulseInHandler(String data){
    int pin = Str2int(data);
    long duration;
    if(pin <=0){
          pinMode(-pin, INPUT);
          duration = pulseIn(-pin, LOW);
    }else{
          pinMode(pin, INPUT);
          duration = pulseIn(pin, HIGH);
    }
    Serial.println(duration);
}

void pulseInSHandler(String data){
    int pin = Str2int(data);
    long duration;
    if(pin <=0){
          pinMode(-pin, OUTPUT);
          digitalWrite(-pin, HIGH);
          delayMicroseconds(2);
          digitalWrite(-pin, LOW);
          delayMicroseconds(5);
          digitalWrite(-pin, HIGH);
          pinMode(-pin, INPUT);
          duration = pulseIn(-pin, LOW);
    }else{
          pinMode(pin, OUTPUT);
          digitalWrite(pin, LOW);
          delayMicroseconds(2);
          digitalWrite(pin, HIGH);
          delayMicroseconds(5);
          digitalWrite(pin, LOW);
          pinMode(pin, INPUT);
          duration = pulseIn(pin, HIGH);
    }
    Serial.println(duration);
}

void SV_add(String data) {
    String sdata[3];
    split(sdata,3,data,'%');
    int pin = Str2int(sdata[0]);
    int min = Str2int(sdata[1]);
    int max = Str2int(sdata[2]);
    int pos = -1;
    for (int i = 0; i<8;i++) {
        if (servo_pins[i] == pin) { //reset in place
            servos[pos].detach();
            servos[pos].attach(pin, min, max);
            servo_pins[pos] = pin;
            Serial.println(pos);
            return;
            }
        }
    for (int i = 0; i<8;i++) {
        if (servo_pins[i] == 0) {pos = i;break;} // find spot in servo array
        }
    if (pos == -1) {;} //no array position available!
    else {
        servos[pos].attach(pin, min, max);
        servo_pins[pos] = pin;
        Serial.println(pos);
        }
}

void SV_remove(String data) {
    int pos = Str2int(data);
    servos[pos].detach();
    servo_pins[pos] = 0;
}

void SV_read(String data) {
    int pos = Str2int(data);
    int angle;
    angle = servos[pos].read();
    Serial.println(angle);
}

void SV_write(String data) {
    String sdata[2];
    split(sdata,2,data,'%');
    int pos = Str2int(sdata[0]);
    int angle = Str2int(sdata[1]);
    servos[pos].write(angle);
}

void SV_write_ms(String data) {
    String sdata[2];
    split(sdata,2,data,'%');
    int pos = Str2int(sdata[0]);
    int uS = Str2int(sdata[1]);
    servos[pos].writeMicroseconds(uS);
}

void sizeEEPROM() {
    Serial.println(E2END + 1);
}

void EEPROMHandler(int mode, String data) {
    String sdata[2];
    split(sdata, 2, data, '%');
    if (mode == 0) {
        EEPROM.write(Str2int(sdata[0]), Str2int(sdata[1]));
    } else {
        Serial.println(EEPROM.read(Str2int(sdata[0])));
    }
}

void SerialParser(void) {
  char readChar[64];
  Serial.readBytesUntil(33,readChar,64);
  String read_ = String(readChar);
  //Serial.println(readChar);
  int idx1 = read_.indexOf('%');
  int idx2 = read_.indexOf('$');
  // separate command from associated data
  String cmd = read_.substring(1,idx1);
  String data = read_.substring(idx1+1,idx2);

  // determine command sent
  if (cmd == "dw") {
      DigitalHandler(1, data);
  }
  else if (cmd == "dr") {
      DigitalHandler(0, data);
  }
  else if (cmd == "aw") {
      AnalogHandler(1, data);
  }
  else if (cmd == "ar") {
      AnalogHandler(0, data);
  }
  else if (cmd == "pm") {
      ConfigurePinHandler(data);
  }
  else if (cmd == "ps") {
      pulseInSHandler(data);
  }
  else if (cmd == "pi") {
      pulseInHandler(data);
  }
  else if (cmd == "ss") {
      SS_set(data);
  }
  else if (cmd == "sw") {
      SS_write(data);
  }
  else if (cmd == "sr") {
      SS_read(data);
  }
  else if (cmd == "sva") {
      SV_add(data);
  }
  else if (cmd == "svr") {
      SV_read(data);
  }
 else if (cmd == "svw") {
      SV_write(data);
  }
 else if (cmd == "svwm") {
      SV_write_ms(data);
  }
  else if (cmd == "svd") {
      SV_remove(data);
  }
  else if (cmd == "version") {
      Version();
  }
  else if (cmd == "to") {
      Tone(data);
  }
  else if (cmd == "nto") {
      ToneNo(data);
  }
  else if (cmd == "cap") {
      readCapacitivePin(data);
  }
  else if (cmd == "so") {
      shiftOutHandler(data);
  }
  else if (cmd == "si") {
      shiftInHandler(data);
  }
  else if (cmd == "eewr") {
      EEPROMHandler(0, data);
  }
  else if (cmd == "eer") {
      EEPROMHandler(1, data);
  }
  else if (cmd == "sz") {
      sizeEEPROM();
  }
}

void setup()  {
  Serial.begin(115200);
    while (!Serial) {
      ; // wait for serial port to connect. Needed for Leonardo only
    }
  Serial.println("connected");
}

void loop() {
  SerialParser();
}

Python Code For Robot Arm Controller Using Arduino :

#!/usr/bin/env python
"""
 Blinks an LED on digital pin 13
 in 1 second intervals
"""

from Arduino import Arduino
import time

board = Arduino() # plugged in via USB, serial com at rate 115200
board.pinMode(13, "OUTPUT")

while True:
    board.digitalWrite(13, "LOW")
    time.sleep(1)
    board.digitalWrite(13, "HIGH")
    time.sleep(1)

Hey guys finally all coding work done so you need to customize it and then impress to your …………….!!!

Resource : Arduino official site

BEST OF LUCK!!

Tags: , , , ,

sachin Pagar

I am Mr. Sachin pagar Embedded software engineer, the founder of Sach Educational Support(Pythonslearning), a Passionate Educational Blogger and Author, who love to share the informative content on educational resources.

Leave a Reply