SEGMENTED AND SHIELDED STRUCTURES FOR REDUCTION OF THERMAL EXPANSION-INDUCED TILT ERRORS

摘要

The results of the thermal study of the HPM structure demonstrate the feasibility of a segmented design for modular serial assemblies, such as instrumentation structures including microscopes and high-precision reconfigurable industrial equipment such as large coordinate measuring machines or assembly robots. The design significantly reduces the thermal sensitivity of a tubular structure, while maintaining structural integrity and offering the flexibility of disassembly, reconfiguration, and reassembly using kinematic couplings. Insulation and shielding is shown to significantly reduce steady state thermal errors. Experimental results validate use of sequential thermal and structural finite element simulations for design optimization of segmented structures based on steady-state drift approximations. Measurement and modeling of the performance of the structure designs under fluctuating heat inputs will be performed next, after which a new structure will be built and tested in operation as a high-precision microscope.