Checkweigher modeling using dynamical subsystems

The accuracy and throughput rate of checkweigher, i.e., the performance of a dynamic weighing system, has improved considerably over the last ten years but the models adopted in the past have become less relevant as they are unable to describe and identify in detail the causes of weighing signal disturbances and therefore do not reflect the true characteristics of the modern checkweigher. As consequence, any further improvements in the performance become restricted or even halted. It is important in this alternative approach to break the dynamic system carefully into logical subsystems that can simplify the analysis, reflect the new technology and predict characteristics that would help the design and development of the mechanical, electrical, optical and computer subsystems. One such earlier model (Masubuchi et al., 1981) has been used as a basis to apply this subsystem technique. The results of the simulation work, compared to the actual weighing signal, indicate definite improvements over the original model but show up simultaneously the differences and limitations of the new model. These limitations suggest that the geometry of mechanical subsystem must be defined and understood comprehensively. Future work should be able to detail the geometry and therefore determine the desired model and hence bring enormous benefits to the designer who can then construct a subsystem with the optimal or desired performance