Issues Using ServoEasing Library for Real-Time Servo Control

Projects Programming
1

Hi all,

I'm fairly new to coding (have done projects here and there for uni but not much outside that), and I am attempting to create a module that can control at max 32 servos through two PCA9685's and an Arduino UNO R4 Minima. My current plan is to use four potentiometers to dictate the speed, position, and upper/lower limits of the servos, as well as a rotary encoder to select which servo is being controlled.

Alas, it seems I can't get past the very first hurdle, which is updating the servo's position in real time. I can only seem to get the servo to "follow" the potentiometer, as the only update function that moves the servo is the "updateAndWaitForAllServosToStop()" function.

Attached below is my code.

#include <Arduino.h>

#define USE_PCA9685_SERVO_EXPANDER 
#define USE_SERVO_LIB

#include <Servo.h>
#include "ServoEasing.hpp"
#include <Wire.h>

// Defining servo channels on PCA
#define SERVO1_PIN 0

ServoEasing Servo1(PCA9685_DEFAULT_ADDRESS);

int potpin = 0;
int potpin2 = 1;
int val;
int val2;
uint8_t servonum = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  delay(200);
  Servo1.InitializeAndCheckI2CConnection(&Serial);
  Servo1.attach(SERVO1_PIN, 45);
}

void loop() {
  // put your main code here, to run repeatedly:
  val = analogRead(potpin);
  val = map(val, 0, 1023, 0, 90);

  //val2 = analogRead(potpin2);
  //val2 = map(val2, 0, 1023, 10, 90);

  Serial.print("Position: ");
  Serial.println(val);

  //Serial.print("   Speed: ");
  //Serial.print(val2);

  Servo1.setSpeed(270);
  Servo1.easeTo(val);
  updateAndWaitForAllServosToStop();
}

/*
void func() {
  val = analogRead(potpin);
  val = map(val, 0, 1023, 0, 90);
  Serial.println(val);
  Servo1.setSpeed(10);
  Servo1.startEaseTo(val);
  delay(5);
} 
*/

Any assistance would be greatly appreciated, especially anyone who has experience with using this library. I have tried using other servo libraries but have struggled to find any that allow the kind of smooth movement and control that this library provides. If anyone has recommendations for other libraries they are most welcome too.

2

It may simply be a case of the ServoEasing library not supporting the R4. It's not listed in the supported architectures. What happens if you try your sketch on an R3?

3

That's a good point! I'll grab an R3 and report back with the results.

4

Tried out the code on an older Mega and the "update()" function worked perfectly. Looks like I'll be going out and buying a new R3.

Cheers!

EDIT: Further testing has revealed that the "update()" function operates the same as the other one. It is working on the Mega at least, but still has the following issue. This time around though, the code doesn't progress until the servo has reached it's position, meaning the potentiometer value is not read until the servo has stopped moving. Very strange. If anyone has a workaround for this that would be appreciated.