Balance Ball game with two vibration motor

BalanceBallWithTwoVib.ino

/*
  Balancing Ball - Arduino part
  More info: https://itp.jasongao.me/physical-computing/week-8-synchronous-serial

  Arranged from LSM6DS3 example by Riccardo Rizzo
*/
#include <Arduino_LSM6DS3.h>

const int leftVibPin = 2;
const int rightVibPin = 3;

int vibration[2] = {0, 0};

void setup() {
  Serial.begin(9600);
  while (!Serial);

  if (!IMU.begin()) {
    Serial.println("Failed to initialize IMU!");

    while (1);
  }
}

void loop() {
  int index = 0;
  while (Serial.available() > 0) {
    int inByte = Serial.read();
    if (inByte == '\n') break;
    vibration[index] = inByte;
    index++;
  }

  analogWrite(leftVibPin, vibration[0]);
  analogWrite(rightVibPin, vibration[1]);

  float x, y, z;

  if (IMU.accelerationAvailable()) {
    IMU.readAcceleration(x, y, z);

    Serial.print(x);
    Serial.print(',');
    Serial.print(y);
    Serial.print(',');
    Serial.println(z);
  }
}