A mobile apparatus , comprising: a self-propelled mobile carriage including a frame ; a pedestal pivotally mounted to said frame for pivoting about first and second substantially orthogonal pivot axes ; a boom having a proximal portion pivotally mounted to said pedestal , said boom defining a boom lumen; a cutting apparatus ; a connection apparatus rotatably connecting said cutting apparatus to a distal portion of said boom for rotation of said cutting apparatus about an actuator axis , characterised in that said connection apparatus being connected to said boom with a feed manifold positioned within said boom lumen, said connection apparatus including: (i) a rotary actuator having a housing defining a chamber , a shaft having first and second ends and extending axially through said chamber for rotation relative to said housing about said actuator axis ; and (ii) a pressurized fluid circuit for delivery of pressurized fluid through said rotator actuator to said cutting apparatus , said circuit having the feed manifold at said first end of said shaft , a delivery manifold at said second end of said shaft , and first and second channels fluidically coupling said feed manifold to said delivery manifold axially through said shaft , wherein said feed and delivery manifolds are rotatable with said shaft relative to said housing . a self-propelled mobile carriage including a frame ; a pedestal pivotally mounted to said frame for pivoting about first and second substantially orthogonal pivot axes ; a boom having a proximal portion pivotally mounted to said pedestal , said boom defining a boom lumen; a cutting apparatus ; a connection apparatus rotatably connecting said cutting apparatus to a distal portion of said boom for rotation of said cutting apparatus about an actuator axis , characterised in that said connection apparatus being connected to said boom with a feed manifold positioned within said boom lumen, said connection apparatus including: (i) a rotary actuator having a housing defining a chamber , a shaft having first and second ends and extending axially through said chamber for rotation relative to said housing about said actuator axis ; and (ii) a pressurized fluid circuit for delivery of pressurized fluid through said rotator actuator to said cutting apparatus , said circuit having the feed manifold at said first end of said shaft , a delivery manifold at said second end of said shaft , and first and second channels fluidically coupling said feed manifold to said delivery manifold axially through said shaft , wherein said feed and delivery manifolds are rotatable with said shaft relative to said housing . (i) a rotary actuator having a housing defining a chamber , a shaft having first and second ends and extending axially through said chamber for rotation relative to said housing about said actuator axis ; and (ii) a pressurized fluid circuit for delivery of pressurized fluid through said rotator actuator to said cutting apparatus , said circuit having the feed manifold at said first end of said shaft , a delivery manifold at said second end of said shaft , and first and second channels fluidically coupling said feed manifold to said delivery manifold axially through said shaft , wherein said feed and delivery manifolds are rotatable with said shaft relative to said housing . <EOS>