Advanced Resource Planning

Advanced Resources Planning hits the bottom of what we know as aggregate planning. This approach differs from other approaches in the way that it explicitly recognizes the stochastic nature of manufacturing systems. Therefore it is an ideal high level tuning and planning tool which can be used in various planning environments like MRP, ERP, JIT, Load Oriented Planning, Theory of Constraints, Finite Scheduling, POLCA systems, and perhaps many more. The main purpose is to set aggregate planning parameters right before diving into any other operational planning decision. In this sense, we opt to offer realistic lead time estimations, lot sizes, utilization levels, customer service levels and quoted delivery times. The underlying approach is a waiting line network, which is heavily adapted in order to make it useful for planning purposes. The main feature is that both input parameters and output parameters are considered as stochastic variables. In this way it allows us to model manufacturing environments in a more realistic and intuitive way, including all kinds of uncertainty and variability. As a consequence, the output of the planning effort is also a stochastic variable: it has an average, a variance entire lead time distribution. The latter makes it possible to obtain customer service level or to establish realistic delivery times, which can be met with a high probability. This mathematical approach as such is not suited for people operating a manufacturing system. We translated the theoretical foundations into what is called ‘Capacity and Variability Analysis, (CVA)’. We illustrate the approach with software, named i-CLIPS, and we review some implementations.