Plinko Token Drop

ctamney · August 14, 2023, 8:57pm

Hello, I work at a rehab center and am working to set up a system that releases a little token into a plinko board. Currently I am using a stepper motor to move a contraption back and forth and then 2 mini servos motors that open and release the token. Upon pushing a button, the stepper moves a random number of steps and then the 2 servos open 90 degrees. I am trying to figure out how to either set up limit switches or one homing switch for the stepper motor. I am using a 5V 28BYJ-48 with a ULN2003 and Arduino uno. I attached my code, in the set up I added a second button because I have been playing around with different things.

#include <Servo.h>
#include <Stepper.h>                           // include stepper library
int revolution = 2038;              // the number of steps in one revolution of your motor (28BYJ-48)
Stepper stepper(revolution, 8, 10, 9, 11); 
int buttonPin=3;
int buttonPin1=5;

Servo servo1;
Servo servo2;

int buttonState = 0;      
int buttonState1 = 0;

void setup() {
  Serial.begin(9600);  
    servo1.attach(4);
  servo2.attach(7);
    pinMode(8, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, OUTPUT);
servo1.write(0);
servo2.write(180);
delay(2000);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(buttonPin1,INPUT_PULLUP);
 
}

void loop() {
  delay(100);
  buttonState = digitalRead(buttonPin); 
  buttonState1 = digitalRead(buttonPin1); 

  uint8_t i;
  
if((buttonState==LOW)){
    stepper.setSpeed(10);       
  stepper.step(random(-5000, 5000));    
  delay(1000); 
    Serial.println("i entered");
   servo1.write(90);
  servo2.write(90);
  delay(1000);
servo1.write(0);
servo2.write(180);
delay(1000); 
}               

else{
}
}

ruilviana · August 14, 2023, 9:44pm

You are using pin 7 to control a servo2.
But pin 7 is not PWM, so it doesn't control the servo.
Sorry. my mistake.

anon56112670 · August 14, 2023, 9:46pm

Say that back to yourself, but slowly.

xfpd · August 14, 2023, 11:00pm

Treat it like a pushbutton.

.
.
    stepper.step(random(-5000, 5000));
    if((buttonState1==LOW)){ // limit switch is button1
      // something
    }
.
.

ctamney · August 15, 2023, 2:05pm

this seems to not do anything. but maybe my code is wrong.

#include <Servo.h>
#include <Stepper.h>                           // include stepper library
int revolution = 2038;              // the number of steps in one revolution of your motor (28BYJ-48)
Stepper stepper(revolution, 8, 10, 9, 11); 
int buttonPin=3;
int buttonPin1=5;

Servo servo1;
Servo servo2;

int buttonState = 0;      
int buttonState1 = 0;

void setup() {
  Serial.begin(9600);  
    servo1.attach(4);
  servo2.attach(7);
    pinMode(8, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, OUTPUT);
servo1.write(0);
servo2.write(180);
delay(2000);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(buttonPin1,INPUT_PULLUP);

}

void loop() {
  delay(100);
  buttonState = digitalRead(buttonPin); 
  buttonState1 = digitalRead(buttonPin1); 

  uint8_t i;
  
if((buttonState==LOW)){
    stepper.setSpeed(10);       
  stepper.step(random(-5000, 5000));    
if((buttonState1==LOW)){
  stepper.setSpeed(10);
  stepper.step(random(-50,-2038));
  }
  delay(1000); 
    Serial.println("i entered");
   servo1.write(90);
  servo2.write(90);
  delay(1000);
servo1.write(0);
servo2.write(180);
delay(1000); 
}               

else{
}
}

xfpd · August 15, 2023, 3:52pm

When you start the steppermotor using the step() command, the steppermotor continues to receive step pulses until your random steps is reached. I think you should try this:

Get a random number and direction, as you did random (-5000, 5000) but as a variable
Step your motor ONE step
Check the if limit switch, then stop
Check if steps is equal to random number, then stop
Go to 2.

ctamney · August 15, 2023, 4:58pm

That makes sense. I am still very new to Arduino. Could you help me better understand what the code for that would look like?
I tried this but know it is likely wrong, as it made no changes.

#include <Servo.h>
#include <Stepper.h>                           // include stepper library
int revolution = 2038;              // the number of steps in one revolution of your motor (28BYJ-48)
Stepper stepper(revolution, 8, 10, 9, 11); 
int buttonPin=3;
int buttonPin1=5;
int stepCount = 0;

Servo servo1;
Servo servo2;

int buttonState = 0;      
int buttonState1 = 0;

void setup() {
  Serial.begin(9600);  
    servo1.attach(4);
  servo2.attach(7);
    pinMode(8, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, OUTPUT);
servo1.write(0);
servo2.write(180);
delay(2000);
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(buttonPin1,INPUT_PULLUP);

 
}

void loop() {
  delay(100);
  buttonState = digitalRead(buttonPin); 
  buttonState1 = digitalRead(buttonPin1); 

  uint8_t i;
  

  
if((buttonState==LOW)){
    stepper.setSpeed(10);       
  stepper.step(random(-5000, 5000));
  stepCount++;     
if((buttonState1==LOW)){
  stepper.setSpeed(10);
  stepper.step(random(-50,-2038));
  }
  delay(1000); 
    Serial.println("i entered");
   servo1.write(90);
  servo2.write(90);
  delay(1000);
servo1.write(0);
servo2.write(180);
delay(1000); 
}

xfpd · August 15, 2023, 5:37pm

Okay... see if this makes sense, and if not, we will try again... BUT FIRST, in reading my writing, I think the order should be changed to:

Get a random number
Check the limit switch
Check if steps taken is equal to random number
Step motor one step
go to 2.

Step 1. You have this...

Try this:

int randomSteps;
.
.
randomSteps = random(-5000, 5000);
stepper.step(randomSteps);

Step 2: You have an empty "else" - maybe that was to be the limit switch test. Try putting that in a function... and call the function

void loop() {
  .
  .
  checkLimitSwitch();
 .
 .
}

void checkLimitSwitch() {
  if (buttonState1 == LOW) { // limit switch (red)
    stepper.setSpeed(0);
    stepper.step(0); // this only stops the steppermotor, but not the sketch, it continues to step
    // while(1); // this is not a good way to stop the stepper, but might help until resolved
    // goHome(); // this could be the function you want if the limit switch is reached
  }
}

Step 3: In step 4 you will step the steppermotor one step, but you need to stop the motor from stepping if it has reached "randomSteps"

if (stepsTaken == randomSteps)
    // goHome(); // this could be the function you want if randomSteps is reached

Step 4:

 else // this 'else' is from failing 'if (stepsTaken == randomSteps)
    stepper.step(1); // steppermotor takes one step

Setp 5: "Wrap" steps 1 through 4 in void loop() where you have the buttons being read

Extras:
z. Move "i entered" into its own function, to be called when stepsTaken equals randomSteps

void ientered() {
  delay(1000);
  Serial.println("i entered");
  servo1.write(90);
  servo2.write(90);
  delay(1000);
  servo1.write(0);
  servo2.write(180);
  delay(1000);
}

a. Make a "goHome" function to send your steppermotor back to the beginning

void goHome() {
  Serial.print("Step to: 0 "); // serial monitor debug information
  stepper.step(randomSteps * -1); // anything "times" minus-one is in the opposite direction
  Serial.println("(Home)"); // serial monitor debug information
}

This is not the only way to make this happen... use your imagination... experience only comes with experiencing... so crash-it-til-you-smash-it.

[edit]
You also have a typo at the top:

// int revolution = 2038; // the number of steps in one revolution of your motor (28BYJ-48)
int revolution = 2048; // the number of steps in one revolution of your motor (28BYJ-48)

[edit]
I have been tinkering with your code...

ctamney · August 23, 2023, 4:37pm

Thank you! I missed this somehow.

xfpd · August 23, 2023, 5:36pm

Try your code, revised, in this simulation

system · February 19, 2024, 5:36pm

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Plinko Token Drop

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