Analysis of Uncertainties in a Structure of Parts

A structure bui l t from parts w i l l not f i t perfectly. The amount of uncertainty in the relat ive positions of the parts can be predicted from the dimensions of the mated parts and their tolerances. The tolerances and sizes of the parts' features are analysed for each possible contact in turn to find constraints on the part positions. The combined effect of these constraints is then found allowing decisions to be made on whether the parts f i t sa t is fac tor i ly . Applications include tolerance checking during design and o f f l ine programming of robot assembly.