Joystick - Freeze Arduino Program (App: Android)

Solved
,
1

Hey
I am currently working on a project in Arduino for school, with Blynk. I use the app for Android.

This is my first project in Arduino / Blynk. The code is not yet optimal, but it works. Or at least partly.
I control 2 servo motors via inverse kinematics. I’m using an Arduino Mega + Ethernet Shield.

I use a joystick (V15 -> x and V16 -> y). If I move the joystick once, the program freezes.

I’ve already tried using sliders (only as a test), but that also has the same result. The joystick is set to 1 second. Merge / split also provide the same result. I’ve been searching for a while, hope you can tell me where it goes wrong.

I don’t use the timer to write data back to the app. I use a delay. So that data is certainly not exchanged more than 10 times per second. (see delay for ExportData).

Thanks in advance!

// Bibliotheken
#include <SPI.h> // Communicatie tussen Arduino en SD-kaart 
#include <Ethernet.h> // Ethernetbibliotheek
#include <BlynkSimpleEthernet.h> // Blynkethernetbibliotheek
#include <Servo.h>  // Servobibliotheek 

// Constanten
const float d12 = 42;
const float d13 = 80;
const float d24 = 80;
const float d35 = 100;
const float d45 = 100;
const float d56 = 20;
const float y1 = 0;
const float y2 = 0;

const float a456 = 2.094395;

const int L_laag = 600;         // Servo_L onderlimiet
const int L_hoog = 2000;      // Servo_L bovenlimiet
const int R_laag = 900;         // Servo_R onderliemiet
const int R_hoog = 2400;      //Servo_R bovenlimiet

// Variabelen
float x = 0;
float y = 100;
float d46;
float a465;
float d26x;
float d26y;
float alfa2;
float d26;
float a426;
float theta2 = 2123.78;              // Initiële stand Servo_R
float a264;
float alfa5;
float x5;
float y5;
float d15x;
float d15y;
float alfa1;
float d15;
float a315;
float theta1 = 901.99;       // Initiële stand Servo_L

const float pi = M_PI;          // Opslaan van Pi in een handig formaat
float theta1_old = 901.99;    // Vergelijkingsvariabele voor theta 1
float theta2_old = 2123.78;    // Vergelijkingsvariabele voor theta 2
float x_old = 0;                        // Vergelijkingsvariabele voor X
float y_old = 100;                   // Vergelijkingsvariabele voor Y

// Servomotoren
Servo Servo_L;                       // Servomotor Links
Servo Servo_R;                      // Servomotor Rechts

// Connecties
#define SERVO_L_PIN   40           // SERVO_L_PIN koppelen aan pin 40
#define SERVO_R_PIN   41           // SERVO_R_PIN koppelen aan pin 41

// Noodzakelijke connecties Blynk:
#define BLYNK_DEBUG
#define BLYNK_PRINT Serial
char auth[] = "ZlwrQh0809oBgdHZRqg57tKeMJ7n1ZnV";
#define W5100_CS  10
#define SDCARD_CS 4
WidgetTerminal terminal(V12);

BLYNK_WRITE(V15){                            // Import coördinaten via Blynk na push in app
  x = param.asFloat();                            // Input nieuwe X via Blynk                                                                          
  terminal.print("Nieuwe X: ");   
  terminal.println(x);
}

BLYNK_WRITE(V16){                            // Import coördinaten via Blynk na push in app
  y = param.asFloat();                            // Input nieuwe Y via Blynk                                                                         
  terminal.print("Nieuwe Y: ");
  terminal.println(y);
}


// Limieten
float servoLimit (float micros_in, float micros_min, float micros_max) {   // Wordt uitgevoerd in subprogramma: Output
  if (micros_in > micros_max) micros_in = micros_max;   // Indien waarde lager dan onderlimiet: gebruik onderlimiet
  if (micros_in < micros_min) micros_in = micros_min;     // Indien waarde hoger dan bovenlimiet: gebruik bovenlimiet
  return micros_in;            // Teruggeven van de correcte waarde
}


// Setup (éénmalige uitvoering van code)
void setup()
{
  Serial.println("Uitvoeren Setup");
  // Servomotoren koppelen aan de correcte uitgangen
  Servo_L.attach(SERVO_L_PIN);            // Servo_L koppelen met SERVO_L_PIN
  Servo_R.attach(SERVO_R_PIN);           // Servo_R koppelen met SERVO_R_PIN

  // Seriële monitor activeren
  Serial.begin(9600);                                // Baudrate van seriële monitor vastleggen
  while (!Serial);                                        // Wachten tot de seriële poort geconecteerd is

  //Servomotoren in startpositie plaatsen
  Servo_L.write(theta1);                           // Servo_L plaatsen in positie theta 1
  Servo_R.write(theta2);                           // Servo_R plaatsin in positie theta 2

  // Uitschakelen SD-kaart
  pinMode(4, OUTPUT);
  digitalWrite(4, HIGH);
  
  // Authenticatie Blynck uitvoeren
  Blynk.begin(auth);

}


/*  ******************************************************************************
    HOOFDPROGRAMMA
*/

void loop()
{
  Blynk.run();               // Uitvoeren Blynk
  InverseKinematica();       // Uitvoeren subprogramma: Inverse kinematica
  Output();                  // Uitvoeren subprogramma: Controle + aansturen
  delay(200);                // Vertraging
  ExportData();              // Uitvoeren subprogramma: ExportData (naar Blynk)
}



/*  ******************************************************************************
    SUBPROGRAMMA'S
*/


// SUB: Inverse kinematica
void InverseKinematica() 
{
  d46    = sqrt( sq(d45) + sq(d56) - 2 * d45 * d56 * cos(a456) );
  a465   = acos( (sq(d45) - sq(d46) - sq(d56)) / (-2 * d46 * d56) );

  d26x   = x - (d12 / 2);
  d26y   = y - y2;

  alfa2  = atan2(d26y, d26x);

  d26    = sqrt( sq(d26x) + sq(d26y) );

  a426   = acos( (sq(d24) + sq(d26) - sq(d46)) / (2 * d24 * d26) );

  theta2 = alfa2 - a426;

  a426   = acos( (sq(d24) + sq(d26) - sq(d46)) / (2 * d24 * d26) );

  theta2 = R_hoog - 10 * ( ((alfa2 - a426) * 4068) / 71);

  a264   = acos( (sq(d46) + sq(d26) - sq(d24)) / (2 * d46 * d26) );

  alfa5  = alfa2 + pi + a264 - a465;

  x5     = d56 * cos(alfa5) + x;
  y5     = d56 * sin(alfa5) + y;

  d15x   = (-d12 / 2) - x5;
  d15y   = y5 - y1;

  alfa1  = atan2(d15y, d15x);

  d15    = sqrt( sq(d15x) + sq(d15y) );

  a315   = acos( (sq(d13) + sq(d15) - sq(d35)) / (2 * d13 * d15) );

  theta1 = 10 * ( ((alfa1 - a315) * 4068) / 71) + L_laag;
}


// SUB: Output
void Output() 
{
  //  Controle van de limieten
  theta1 = servoLimit(theta1, L_laag, L_hoog);                     // Controle op limeiten Theta 1
  theta2 = servoLimit(theta2, R_laag, R_hoog);                    // Controle op limeiten Theta 2
  Servo_L.write(theta1);                                                        // Aansturen motor Links (theta 1)
  Servo_R.write(theta2);                                                        // Aansturen motor Rechts (theta 2)

  // Uitschrijven gegevens naar seriële poort
  if (theta1 != theta1_old) {                        // Indien theta 1 wijzigt, dan..
    Serial.print("Theta 1 naar: ");
    Serial.println(theta1);
    theta1_old = theta1;                             // Verangen oude theta 1 door nieuwe theta 1
  }

  // Aansturen servo rechts + uitschrijven hoek
  if (theta2 != theta2_old) {                            // Indien theta 2 wijzigt, dan..
    Serial.print("Theta 2 naar: ");
    Serial.println(theta2);
    theta2_old = theta2;                       // Vervangen oude theta 2 door nieuwe theta 2
  }
}


// SUB: ExportData
void ExportData()
{
  terminal.println(F("Export Data."));
  Blynk.virtualWrite(V0, theta1);          // Sturen theta1 naar virutele pin 0
  terminal.println(theta1);
  Blynk.virtualWrite(V1, theta2);         // Sturen theta2 naar virtuele pin 1
  terminal.println(theta2);
  Blynk.virtualWrite(V2, x);                 // Sturen x naar virtuele pin
  terminal.println(x);
  Blynk.virtualWrite(V3, y);                 // Sturen y naar virtuele pin 3
  terminal.println(y);
}
2

Have a read of this document:

Then look at the structure of your code and ask yourself why you are calling all of these functions that do lengthy calculations and output data to Blynk every time the void loop executes.

The sensible thing (in my mind at least) would be to call these only when the joystick widget moves - in other words in the BLYNK_WRITE(V15) and BLYNK_WRITE(V16) callback functions.

Pete.

1 Like
3

Hi Pete

I have read this information before. If I understand correctly, the timer only avoids uploading the data to the app.

The calculations are not a problem, are they? These are separate from Blynk? Or should I implement that everything can only be bought out after changing the position of the joystick?

In the meantime I have replaced the delay in my main loop with a timer function. In other words I run “DataExport” with a timer every second.

Incidentally, I have tried the following, but this doesn’t seem to work either.

void loop()
{
  Blynk.run();                     // Uitvoeren Blynk
  if (x != x_old || y != y_old){
    timer.run();                   // Uitvoeren van de timer, iedere seconde
    InverseKinematica();           // Uitvoeren subprogramma: Inverse kinematica
    Output();                      // Uitvoeren subprogramma: Controle + aansturen
  }

}

Stupid idea? Or poorly executed?

Extra info:
x = virtual pin, Blynk data from Joystick
y = virtual pin, Blynk data from Joystick
x and y are the coordinators of the position the robot is currently in.

(Edit: clean code + extra info)

4

I wasn’t suggesting that you implement a timer. Timers are great solutions when you want to do something like read a sensor every 10 seconds or check if the state of a switch has clandestine every few hundred milliseconds, but neither of these are the case here.

The reason I linked to the document is because it explains how the void loop should be running hundreds if not thousands of timer per second and that the Blynk library is expecting Blynk.run to be processed on this sort of frequency.

As I said before, you have a simple solution which is to use the BLYNK_WRITE callbacks to trigger your calculations and Blynk.virtualWrites.

You’re working with a single core processor with a slow clock speed and limited memory. Your code needs to be tight, especially if you are doing lots of floating point maths (which you are).
However, I’d guess that the point of your course is to learn the basics of good programming.
No self respecting programmer would write code that performs unnecessary complex calculations hundreds of times per second when they have a perfectly useable way of triggering these calculations on an ‘as and when needed’ basis - even if the processor is more than capable of handling this (which yours isn’t).

Pete.

5

Hey

I rebuilt my code. I started with the sample program from Blynk.

In the next step I added the ‘inverse kinematics’. Until now no problems. Here I noticed when using the joystick, that after establishing the first connection, the values ​​are forwarded faster than indicated in the app (1 second is indicated in the app). If I notice that too much data is arriving by consulting the debug monitor. And I stop moving the joystick in time, there is no problem. From here I can move without problems, exchanging the data 1x per second.

Then I only added the essence of the servo motors (initialization [start x and y coordinate] + libraries). Here, Blynk started to lose the connection even without anything being done. After moving the joystick, the connection is terminated 98% of the time.

Are there any possible solutions?

Another possible problem is the firewall that can cause problems internally here. Later today I can test the program without the intervention of a firewall. But I think the problem is with the servo lib.?

New Code:

#define BLYNK_PRINT Serial

// Bibliotheken
#include <SPI.h>                                  // Communicatie tussen Arduino en SD-kaart 
#include <Ethernet.h>                             // Ethernetbibliotheek
#include <BlynkSimpleEthernet.h>                  // Blynkethernetbibliotheek
//#include <Servo.h>                              // Servobibliotheek 

char auth[] = "m2SXhYGSk3IvBFNZ_d0Lg2gevlCYViiZ";

#define W5100_CS  10
#define SDCARD_CS 4

// Constanten
const float d12 = 42;
const float d13 = 80;
const float d24 = 80;
const float d35 = 100;
const float d45 = 100;
const float d56 = 20;
const float y1 = 0;
const float y2 = 0;

const float a456 = 2.094395;

const int L_laag = 600;                       // Servo_L onderlimiet
const int L_hoog = 2000;                      // Servo_L bovenlimiet
const int R_laag = 900;                       // Servo_R onderliemiet
const int R_hoog = 2400;                      // Servo_R bovenlimiet

// Variabelen
float x = 0;
float y = 100;
float d46;
float a465;
float d26x;
float d26y;
float alfa2;
float d26;
float a426;
float theta2 = 2123.78;                         // Initiële stand Servo_R
float a264;
float alfa5;
float x5;
float y5;
float d15x;
float d15y;
float alfa1;
float d15;
float a315;
float theta1 = 901.99; 

const float pi = M_PI;                           // Opslaan van Pi in een handig formaat
float theta1_old = 901.99;                    // Vergelijkingsvariabele voor theta 1
float theta2_old = 2123.78;                  // Vergelijkingsvariabele voor theta 2
float x_old = 0;                                     // Vergelijkingsvariabele voor X
float y_old = 100;                                 // Vergelijkingsvariabele voor Y

// Servomotoren
//Servo Servo_L;                                   // Servomotor Links
//Servo Servo_R;                                  // Servomotor Rechts

// Connecties
//#define SERVO_L_PIN   40              // SERVO_L_PIN koppelen aan pin 40
//#define SERVO_R_PIN   41             // SERVO_R_PIN koppelen aan pin 41

// Limieten
float servoLimit (float micros_in, float micros_min, float micros_max) {  // Wordt uitgevoerd in subprogramma: Output
  if (micros_in > micros_max) micros_in = micros_max;      // Indien waarde lager dan onderlimiet: gebruik onderlimiet
  if (micros_in < micros_min) micros_in = micros_min;     // Indien waarde hoger dan bovenlimiet: gebruik bovenlimiet
  return micros_in;                                   // Teruggeven van de correcte waarde
}


BLYNK_WRITE(V1) {
  x = param.asInt();

}

BLYNK_WRITE(V2) {
  y = param.asInt();
}

void setup()
{
  // Debug console
  Serial.begin(9600);

  pinMode(SDCARD_CS, OUTPUT);
  digitalWrite(SDCARD_CS, HIGH); // Deselect the SD card
  WidgetTerminal terminal(V12);
  Blynk.begin(auth);

  // Servomotoren koppelen aan de correcte uitgangen
//  Servo_L.attach(SERVO_L_PIN);                              // Servo_L koppelen met SERVO_L_PIN
//  Servo_R.attach(SERVO_R_PIN);                            // Servo_R koppelen met SERVO_R_PIN
  
  //Servomotoren in startpositie plaatsen
// Servo_L.write(theta1);                                       // Servo_L plaatsen in positie theta 1
//  Servo_R.write(theta2);                                   // Servo_R plaatsin in positie theta 2 
}



/*  ******************************************************************************
    HOOFDPROGRAMMA
*/

void loop()
{
  Blynk.run();
  if (x != x_old or y != y_old){
    InverseKinematica();           // Uitvoeren subprogramma: Inverse kinematica
    Output();                      // Uitoveren subprogramma: Output
    ExportData();                  // Uitvoeren subprogramma: ExportData
  }
}


/*  ******************************************************************************
    SUBPROGRAMMA'S
*/

// SUB: Inverse kinematica
void InverseKinematica() 
{
  d46    = sqrt( sq(d45) + sq(d56) - 2 * d45 * d56 * cos(a456) );
  a465   = acos( (sq(d45) - sq(d46) - sq(d56)) / (-2 * d46 * d56) );

  d26x   = x - (d12 / 2);
  d26y   = y - y2;

  alfa2  = atan2(d26y, d26x);

  d26    = sqrt( sq(d26x) + sq(d26y) );

  a426   = acos( (sq(d24) + sq(d26) - sq(d46)) / (2 * d24 * d26) );

  theta2 = alfa2 - a426;

  a426   = acos( (sq(d24) + sq(d26) - sq(d46)) / (2 * d24 * d26) );

  theta2 = R_hoog - 10 * ( ((alfa2 - a426) * 4068) / 71);

  a264   = acos( (sq(d46) + sq(d26) - sq(d24)) / (2 * d46 * d26) );

  alfa5  = alfa2 + pi + a264 - a465;

  x5     = d56 * cos(alfa5) + x;
  y5     = d56 * sin(alfa5) + y;

  d15x   = (-d12 / 2) - x5;
  d15y   = y5 - y1;

  alfa1  = atan2(d15y, d15x);

  d15    = sqrt( sq(d15x) + sq(d15y) );

  a315   = acos( (sq(d13) + sq(d15) - sq(d35)) / (2 * d13 * d15) );

  theta1 = 10 * ( ((alfa1 - a315) * 4068) / 71) + L_laag;

  // Uitschrijven gegevens naar seriële poort
  if (theta1 != theta1_old) {                                                   // Indien theta 1 wijzigt, dan..
    Serial.print("Theta 1 naar: ");
    Serial.println(theta1);
    theta1_old = theta1;                                                        // Verangen oude theta 1 door nieuwe theta 1
  }

  // Aansturen servo rechts + uitschrijven hoek
  if (theta2 != theta2_old) {                                                   // Indien theta 2 wijzigt, dan..
    Serial.print("Theta 2 naar: ");
    Serial.println(theta2);
    theta2_old = theta2;                                                        // Vervangen oude theta 2 door nieuwe theta 2
  }
  x_old = x; 
  y_old = y;
  Serial.println("Berekening klaar");
}

// SUB: Output
void Output() 
{
  //  Controle van de limieten
  theta1 = servoLimit(theta1, L_laag, L_hoog);                                  // Controle op limeiten Theta 1
  theta2 = servoLimit(theta2, R_laag, R_hoog);                                  // Controle op limeiten Theta 2
//  Servo_L.write(theta1);                                                        // Aansturen motor Links (theta 1)
//  Servo_R.write(theta2);                                                        // Aansturen motor Rechts (theta 2)

  // Uitschrijven gegevens naar seriële poort
  if (theta1 != theta1_old) {                                                   // Indien theta 1 wijzigt, dan..
    Serial.print("Theta 1 naar: ");
    Serial.println(theta1);
    theta1_old = theta1;                                                        // Verangen oude theta 1 door nieuwe theta 1
  }

  // Aansturen servo rechts + uitschrijven hoek
  if (theta2 != theta2_old) {                                                   // Indien theta 2 wijzigt, dan..
    Serial.print("Theta 2 naar: ");
    Serial.println(theta2);
    theta2_old = theta2;                                                        // Vervangen oude theta 2 door nieuwe theta 2
  }
}

// SUB: ExportData
void ExportData()
{
  Blynk.virtualWrite(V10, theta1);      // Sturen theta1 naar virutele pin 0
  Blynk.virtualWrite(V11, theta2);        // Sturen theta2 naar virtuele pin 1
  Blynk.virtualWrite(V12, x);                                                    // Sturen x naar virtuele pin
  Blynk.virtualWrite(V13, y);                                                    // Sturen y naar virtuele pin 3
}

As you can see in the code, everything servo related is disabled by comment. If I do this, the program works. With the exception of the buffer that is sent out after the net start-up (see above, *). If I use the full program, I lose the connection.

Program in which servo is switched off:
Blynk-Servo-Uit

Servo-enabled program:
Blynk

Thanks in advance!

6

Hey!

I found the problem.
This thread may be closed! (I think I closed it myself :wink:)

The past three days I have been looking for the possible problem. As mentioned before I disabled the servos in the above program.

Then I purely physically separated the wiring (EMC). The problem now seems to be resolved.
The signals in the wiring caused the necessary interference, causing the connection to be lost. Presumably the Ethernet board is interfering. (I think).

Have a good weekend! :wave: