Low creep and hysteresis load cell based on a force-to-fluid pressure transformation

In this paper, a low-cost load cell (force sensor) is presented in which th e force to be measured is transformed into a fluid pressure. The design con sists of a boss, attached to a membrane, and a bucket-like structure which encloses a fluid volume. This geometry causes a force to be transformed int o a pressure. We show that this transformation only depends on the geometri cal parameters of the load cell and that it is independent of the Young's m odulus of the membrane resulting in very low creep and hysteresis. Experime ntal results with loads up to 1000 kg show very good repeatability and are in close agreement with both analytical and numerical calculations. (C) 199 9 Elsevier Science S.A. All rights reserved.