Simultaneous servo control - arduino

Question

Stumbling my way thru a problem where I'm trying to move two or more servos at the same time while iterating through multiple arrays. Think of a drum machine, where I may want to hit a snare, bass and high hat all the same time on some beats. Not on others.
byte bass[] = {1,0,1,0};
byte snare[] = {1,1,0,0};
byte hihat[] = {1,1,0,0};
for (int i = 0; i < sizeof(snare); i++)
{
if (i == 1)
{
snare.write(45);
delay(250);
snare.write(0);
dleay(250);
}
else if
{
snare.write(0);
delay(500);
}
}
And so on for each array, each instrument.
As you may see, this won't work because of the delay() and that the two or more loops wouldn't trigger at the same time as the procedural nature.
I understand I could pull this off with some wizardry using millis() instead of using delay().
Tho I'm curious if using a servo driver board would be easier to accomplish what I'm out to do or is millis() the only avenue for me?
Update
After tinkering with millis() for a while, I found myself overcomplicating the task and found a 'close enough' for the task I had in mind by going a simplier route.
#include <Servo.h>
Servo s1;
Servo s2;
Servo s3;
Servo s4;
byte bass[] = {45,0,0,0,45,0,0,0,0,0,0,0,0,0,0,0,45,0,45,0,0,0,0,0,0,0,0,0,45,0,0,0};
byte snare[] = {0,0,0,0,0,0,0,0,45,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,45,0,0,0,0,0,0,0};
byte hihat[] = {45,0,0,0,45,0,0,0,45,0,0,0,45,0,0,0,45,0,0,0,45,0,0,0,45,0,0,0,45,0,0,0};
byte cymb[] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,45,0,0,0,0,0,0,0,0,0,0,0,0,0,45,0,0,0};
void setup() {
Serial.begin(9600);
s1.attach(6);
s2.attach(5);
s3.attach(4);
s4.attach(3);
s1.write(0);
s2.write(0);
s3.write(0);
s4.write(0);
}
void loop()
{
drummer();
}
void drummer()
{
for (int i = 0; i < sizeof(bass); i++)
{
s1.write(bass[i]);
s2.write(snare[i]);
s3.write(hihat[i]);
s4.write(cymb[i]);
delay(250);
}
}

Answer 1

Tho I'm curious if using a servo driver board would be easier to
accomplish what I'm out to do or is millis() the only avenue for me?
Millis() will work. I don't own a servo driver board so I can't say about it but I don't think that would help in running servos simultaneously.
Here is the code using millis(). I just wrote it based on your given example.
byte bass[] = {1,0,1,0};
byte snare[] = {1,1,0,0};
byte hihat[] = {1,1,0,0};
usigned long currentMillis = 0;
unsigned long previousMillis = 0;
const long interval = 250;
const long longInterval = 500;
for (int i = 0; i < sizeof(snare); i++)
{
if (i == 1)
{
snare.write(45);
currentMillis = millis();
if (currentMillis - previousMillis >= interval){
snare.write(0);
}
}
else if
{
if (currentMillis - previousMillis >= longInterval){
snare.write(0);
}
}
}