EXTENDABLE LEG ASSEMBLY FOR POSITION MEASUREMENT APPARATUS

摘要

An extendable leg assembly (8; 30) for a measuring machine, such as a co-ordinate measuring machine, is described. The extendable leg assembly (8; 30) has a first end and a second end and comprises metrology apparatus for measuring the separation between the first end and the second end. The metrology apparatus comprises one or more elongate metrology members (44, 46; 76,78) having a low coefficient of thermal expansion. The extendable leg assembly (8;30) may be attached to one or more platforms (4, 6; 36, 38) by a pivot joint. In a preferred embodiment, the load bearing structure (50, 56) is mechanically isolated from the metrology structure (76,78, 80) of the leg assembly (8; 30).