| Extensive research has been done to solve the problem of machining unique geometries with micron and sub-micron precision surfaces. Fast tool servos are the devices that are capable of producing these unique geometry parts. These fast acting tool holders, capable of machining axis-asymmetric parts, have been used in machining bearing surfaces in internal combustion engines. Machining piston profiles, engine cylinder bores, and cam shafts have been researched significantly in recent past. However, machining piston pin holes, or wrist pins, have minimal devices available for machining this unique geometry.;This thesis aims at solving this problem and proposes a mechanical and controller design of a fast tool servo for machining non-cylinder bores. The tool houses a boring bar that varies the depth of cut dynamically to machine these pin holes. The designed fast tool servo, driven by a piezoelectric actuator, has a first natural frequency of 460 Hz with an operating range of 60 mum. A robust plug-in repetitive controller is designed and implemented for a piston pin hole profile, generating the cutting tool motion. Experimental results demonstrated 45 micron peak-to-peak displacement and 0.57 micron root mean square error for tracking a 200 Hz ellipse profile. |
