| Popis: |
Currently, most plastic products are manufactured using injection molding machines. The quality of plastic products depends largely on the injection force. In a typical force control system of an injection molding machine, force information from the machine environment is obtained by a force sensor. However, force sensors have a few disadvantages in terms of signal noise, sensor cost, narrow bandwidth, etc. We have proposed the use of a reaction force observer based on the two-inertia resonant model. However, this method has some estimated error because of the influence of nonlinear characteristics of the holding process and the screw back-pressure process. The estimation accuracy of the reaction force observer depends on parameter variations and the non-linear friction phenomenon. This paper proposes a new injection force estimation method based on a proposed high-order reaction force observer, which is not influenced by the nonlinear friction phenomenon significantly. This paper evaluates the effectiveness and the sensorless feedback control of the proposed method through experiments. |
