Arduino for sub sea newton gripper

is it possible to control the sub sea newton gripper using a raspberry pi or an arduino. QGC and the pixhawk is not an option

Yes, look at the documentation here, in the Technical details tab.

You can use it as a servo (so any arduino sketch ot raspberry script to control servos should work).
It takes a 3.3 V PWM signal for control, 1500 us is neutral.

For Arduino you can test with the “sweep” example, which will cycle it opening/closing.
Raspberry should habe something similar too.