Production capacity planning
Capacity planning is often a juggling act. Finding the ideal balance between customer demands and organizational capacity involves many dynamic factors. Faced with such complexity, many manufacturing enterprises simply resign and use poor-quality resource planning that is based on either unlimited capacities or constrained capacities - essentially ignoring the actual capacity of the firm.
With the right solution using adaptive resource scheduling with limited capacity, you can balance demand and actual resource capacity and avoid underutilization or failure to meet your customers' needs.
The APS system performs collision-free, situation-based planning of custom filling with limited production resources in mind. The APS system guarantees that the execution of orders takes place in real time intervals and that possible deviations are immediately recognized through the continuous comparison of planned and actual values. The APS system contains adaptive planning algorithms (genetic algorithms working on the principle of artificial evolution and Darwinian principles of selection, mutation and crossover) for optimization based on realistic technological procedures.
The result of the planning algorithms is displayed as a Gantt chart for a better overview.
Scheduling algorithms take into account constraints from the customer by orienting the order of scheduled jobs according to the priority, importance of individual customers, or according to the minimization of internal costs. When planning orders, it is also necessary to take into account technological limitations (e.g. adjusting machines for individual types of products) and storage time and related storage costs, where in some cases the savings resulting from optimized machine adjustment are offset by additional storage costs.
What constitutes the optimal sequence of orders depends on many frequently changing factors, but two important aspects are needed when planning any production:
- A view from the customer's side, in which the emphasis on delivery dates and quality comes first. The priority of individual customers is determined by the production planner.
- A cost-oriented view to minimize production costs.
APS uses simulation to calculate and display different situations with regard to variants, quantities and deadlines. Fully automatic production planning is possible for production processes with few restrictive conditions and clear rules. In the case of more complex planning processes, the decision according to which variant will be produced is up to the management of the company.
Years of experience with the analysis of technological procedures show that the entered values (mainly planned times for individual production operations, times for adjustment, cleaning, etc.) deviate significantly from reality. The reason for this is that the input of values takes place at a certain time before the start of production, based on estimates and time studies, and these values are then not refined during production itself. From this follows an important requirement for the APS adaptive planning function: comparing time values from technological procedures and actual production times and subsequently adjusting technological times according to reality, which enables reliable and accurate production planning.
Recording of current production times is done simply and economically using terminals. Current times related to individual orders and products are recorded here. Statistically calculated average values of these actual times can then be compared with times in technological procedures and it is possible to analyze deviations.
Adaptive production planning must deal with the following complexity of assigned constraints, which are often at odds with the planning objective:
- With regard to the contract:
- Delivery date
- With regard to the production process:
- Minimum or maximum intervals between process steps
- Transport times
- Waiting times (cooling or aging processes)
- With respect to production resources:
- Resource allocation
- Traffic availabilty
- Cleaning and maintenance times
- Availability of quality control resources (metrology, laboratories)
For adaptive planning of a larger number of orders in order to guarantee all delivery dates to customers, APS provides the following:
- Synchronization of the process chain and minimization of unproductive and waiting times
- Collision-free planning of custom filling
Strategies for adaptive production planning and planning algorithms:
- The scheduling algorithm must be able to synchronize a complex process chain and perform collision-free scheduling of a large number of jobs while respecting the availability of production resources.
- Changes in quantity, terms, or exchangeability are entered manually, and the algorithm takes care of the rest.
- The planning result is then displayed, for example, as a Gantt chart.
- The planned data is then compared with the current production data.
There are different strategies for optimization-based job scheduling. A suitable strategy should be selected according to specific conditions:
- APS will receive the earliest possible production start dates based on material availability confirmation from the MRP system.
- Scheduling is done using these dates.
- All production operations are planned so that they take place ahead of time.
- However, it is not always a suitable method.
- This is because if the final product is completed too soon, it can increase its storage costs and it is also possible that the material for production could have been used for a more urgent order.
Therefore, if the delivery date for the customer is set in advance, or if it is only possible to deliver on certain dates, e.g. due to the delivered dates from the carrier, back-planning of orders is recommended.
- In this case, planning is carried out based on the final date of the production order and individual production operations are planned retrospectively.