Quasi-monolithic silicon load cell for loads up to 1000 kg with insensitivity to non-homogeneous load distributions

In this paper, a micromachined silicon load cell (force sensor) is presente d for measuring loads up to 1000 kg. The sensitive surface of 1 cm(2) conta ins a matrix of capacitive sensing elements to make the load cell insensiti ve to non-homogeneous load distributions. The load cell has been realized a nd tested. Measurements on a packaged device show an accuracy of 0.2% of fu ll scale limited by the measurement electronics. An accuracy of 0.03% or be tter is expected to be feasible. The design can be easily adapted for highe r loads by increasing the chip area or using multiple chips in a single pac kage. (C) 2000 Elsevier Science S.A. All rights reserved.