Abstract
A regular office chair was equipped with force transducers, which allow to monitor and to guide the sitting behavior of a person during an office working day. Only four force transducers are required to estimate characteristic parameters for quantifying the biomechanical effect of a certain sitting posture. Based on these parameters, which rely on a simple biomechnical model, a posture cost function was proposed for classification of the sitting posture. Since for posture guidance the posture control system has to be known, a simple approach for identification of the controller parameters is proposed. A framework for designing effective exercises is presented and allows to assess different exercises for improving the person's sitting behavior. The proposed sensor concept of the chair as well the proposed biomechanical model are evaluated by means of laboratory experiments. © 2011 IFAC.