//center
if(joyh >= 410 || joyh <=450)
{
servodireccao.write(115);
}
This should be:
//center
if(joyh >= 410 && joyh <=450)
{
servodireccao.write(115);
}
The former will be true for ALL values of joyh, the latter will only be true when joyh is between 410 and 450.