This boss was so hard!! But after an hour, I made a full guide on how to defeat the Robot, so hopefully this guide helps for you.

#1:You will need the Mega Rocket Cannon (I have never defeated this boss without it.)

#2:Have a lot of weapons (Upgraded ones are always good, you will also want sheild charger or telsa barrier.)

#3:Use up all your weapon ammo (You should die in lava, because on the way to this boss, I know you would be smashing ammo and nanotech crates for health and ammo, and when you die,the crates refill! But the damage you done to the boss dosen't stay the same.)

#4:Go to those turrets and shoot him as good as you can until he shoots those things at you,when he does,jump out.(I think that the things don't do anything to the turret when you're out.)

#5:Go to turret to turret, repeat #4 until you destroy him.

Hope you defeat this boss! :)