Optimizing vacuum grippers of robots for glass sheets handling and developing robots for glass cleaning, it is necessary to solve a number of problems calling for a similar approach to a solution. This paper analyzes deformation behaviour of vacuum gripping elements of vacuum grippers. The extent of deformation safety of an individual suction cup is monitored depending on the vacuum level and loading character. A computer model was suggested and filtered out allowing contact area changes to be observed depending on a friction model and vacuum level.