Standard nozzle for the robot is a rotary (turbo) nozzle, size 0.55 (1,35mm). However, robots that are washing in deep pens has the options to use the double nozzle/shift head valve to reach further in the pen (up to 6 meters). The double nozzle is equipped with a rotary nozzle + a 0-degree nozzle.
The size of the nozzle is carefully calculated to balance the robots weight and keep the robot steady. Do not change nozzle to a bigger/smaller size, it will effect the balance of the robot. A bigger hole in the nozzle will only increase the water flow!
Use a water filter, on the incoming water to the high-pressure washer, for a longer nozzle lifespan.