using arduino tone function on two pin at the same time - c++

Question

I'm trying to make an smart car with Arduino Mega, and I need to turn both of the back wheels on for an specific time sometimes. I've been told that I can set a "digital HIGH" time using tone, But as I need them to work in a same time, Is there a way to set tone for two pins in one line or something to do instead?
Thanks for your help.
#include <Servo.h>
/////////////////////
Servo servo;
/////////////////////
int trig = 12;
int echo = 13;
long duration;
int distance;
int dist_right;
int dist_left;
int ang = 90;
unsigned int value = 255;
unsigned long tone_time = 3000;
float forward_time;
/////////////////////
int ena = 35;
int in1 = 7;
int in2 = 6;
int in3 = 5;
int in4 = 4;
int enb = 47;
/////////////////////
void setup()
{
Serial.begin(9600);
servo.attach(22);
pinMode(trig, OUTPUT);
pinMode(in1, OUTPUT);
pinMode(in2, OUTPUT);
pinMode(in3, OUTPUT);
pinMode(in4, OUTPUT);
pinMode(ena, OUTPUT);
pinMode(enb, OUTPUT);
pinMode(echo, INPUT);
digitalWrite(ena, HIGH);
digitalWrite(enb, HIGH);
}
void loop() {
servo.write(90);
distance = dist();
if(distance<=15)
{
for(ang;ang>=0;ang-=2)
{
servo.write(ang);
delay(30);
}
dist_right = dist();
Serial.println(dist_right);
for(ang;ang<=180;ang+=2)
{
servo.write(ang);
delay(30);
}
dist_left = dist();
Serial.println(dist_left);
for(ang;ang>=90;ang-=2)
{
servo.write(ang);
delay(30);
}
if(dist_right>=dist_left)
{
tone(in3, value, tone_time);
}
else if(dist_right<dist_left)
{
tone(in1, value, tone_time);
}
servo.write(90);
ang=90;
}
else{
forward_time=distance/25;
tone((in1,in3), value, forward_time);
}
}
int dist(){
digitalWrite(trig, LOW);
delayMicroseconds(2);
digitalWrite(trig, HIGH);
delayMicroseconds(10);
digitalWrite(trig, LOW);
duration = pulseIn(echo, HIGH);
distance= duration*0.034/2;
return distance;
}

Answer 1

I'm 99.99% sure, that your motors will not feel the time differencce if you turn them one by one. Try simplest case and you will see.
// Define your wheel control pins (use same as in your mega)
const int motor1Pin = 5;
const int motor1Pin = 6;
// somewhere in setup method
outputMode(motor1Pin, OUTPUT);
outputMode(motor2Pin, OUTPUT);
// Create function to turn motors and remember the time
unsigned long turnMotorsOn(int seconds) {
// turn motors ant return time when they should be stopped
return millis() + seconds * 1000;
}
// In you code check if it is time to turn off
if (millis() > timeWhenTurnMotorsOff) {
// turn them off
}