Keyestudio 4DOF Manual page 139

void loop()
{
// turn right
for(pos1;pos1>0;pos1--)
{
myservo1.write(pos1);
delay(5); // delay 5ms（used to adjust the servo speed）
}
delay(1000);
// open the claw
for(pos4;pos4<100;pos4++)
{
myservo4.write(pos4);
}
delay(1000);
// right servo rotates to 100 degrees
for(pos2;pos2>50;pos2--)
{
myservo2.write(pos2);
delay(5);
}
// left servo rotates to 5 degrees
for(pos3;pos3>50;pos3--)
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