You make it more difficult to help you since you refuse to supply a schematic. How can you build a project without a schematic?
You cannot power the servos with the Uno 5V regulator. That regulator can't supply enough current for a servo and will get hot and shut down. Use a proper external power supply for the servos. Look at the servo data sheets to see what the stall current is and make sure that the servo power supply can handle the combined stall currents.
How much current does the laser draw? It may need an external supply as well.
The newData flag tells the program when a new data packet has arrived so the the new packet can be parsed and acted upon. It is set (to true) when the new packet is read and cleared (to false) when the packet has been taken care of. The flag is declared globally (see scope). Examine the receive code to see where it is declared and used.