Description

Paper Plane Production Line - Discrete Event Simulation Problem

P3I, an international paper plane production company, operates two facilities, one in the UK Midland and the other in Germany. The company employs a semi-automated production line equipped with six robots. The production process consists of six key steps:

Receipt & Inventory: four different paper types (i.e. raw materials) (RM1 - RM4) are received from suppliers and checked for quality. After inspection, they are stored in pallet racks.

Pre-assembly of raw materials: the stored raw materials are picked from racks and pre-processed using machines (PM1 - PM4) to prepare them for assembly.

Assembly kit preparation: human resources create assembly kits (AK1 - AK3) based on design specifications using the pre-processed raw materials.

Paper plane folding: robots fold paper planes (PP1 - PP6) using the assembly kits. Each robot follows specific folding instructions.

Quality Control & Testing: the quality of the paper planes is tested and any defects are identified. Some planes may fail the quality check.
Dispatch: the finished paper planes are prepared for dispatch.

P3I produces six different paper planes, namely PP1, PP2, PP3, PP4, PP5, and PP6. The production operates five days a week from 8:00 a.m. to 17:00, with a one-hour break. Four different types of raw materials (RM1 - RM4) are delivered to the shop floor. The arrival time for each raw material type can be found in Table 1.

Table 1: Description of raw material types and arrival times for each raw material type.

After raw materials arrive, they are inspected within 10 to 15 minutes and stored at pallet racks within 10 to 30 minutes and most likely 15 minutes. Raw materials are then picked from the rack stores and moved to pre-assembly machines (PM1 - PM4) to perform some processing on them before the assembly. The task of material picking takes between 5 to 10 minutes for all the raw material types. The cycle time of each pre-assembly machine for each raw material type can be seen in Table 2.

Table 2: Cycle times of each pre-assembly machine for each raw material type.

At this stage, the assembly kits (AK1 - AK3) for three different paper plane types are prepared by human resources at three assembly benches. Each assembly kit is prepared based on the assembly design, which specifies the raw material composition as summarised in Table 3. The numbers in parentheses indicate the quantity of items required from each raw material for each assembly kit. Additionally, the part of the paper plane that will be constrcucted from each raw material is specified. The assembly kit preparation process typically takes between 1 to 2 hours, with an average duration of 1.5 hours.

Table 3: Composition of Assembly Kits (AKs).

Table 4: Probabilities and cycle times of paper plane folding process.

The robots require maintenance after every 10 folding cycles, taking between 20 to 40 minutes, with most likely to be 30 minutes. Additionally, there is a 10% breakdown rate for each robot.

For each breakdown, the delay will increase by 50% in addition to the maintenance delay for any repair or replacement. Quality control is performed after paper plane folding, with certain probabilities for paper planes failing the quality check, as shown in Table 5. The quality check process adds an average delay of 45 minutes.

Table 5: Probability of paper planes to fail the quality check.

In terms of human resources, the shop floor has five technicians for arrivals checking, storage and pre-assembly. There are also six technicians responsible for assembling the kits, two special technicians for robot maintenance and one quality check officer to perform the quality check procedure after each paper folding. Finally, seven forklifts handle the movement of materials.

Other assumptions:
Buffers/queues can have maximum capacity. However, a buffer/queue with more than 10 entities indicates a bottleneck in the system
The work shift operated from Monday to Friday, 8:00 am - 17:00, with a one-hour break
Please make your assumptions for any remaining parameters/variables
Please note that the ultimate goal of the simulation is to maximise the throughput in the paper plane production process.

Assignment requirements
You are required to create the simulation model in AnyLogic software using the DES technique and run the simulation for 1 year. You also need to write a report based on both the simulation models and compare the results. The report should be between 2000-2500 words with the following structure:

1. Introduction - Provide an overview of the problem, state the aim and objectives, and introduce the conceptual model

2. Model development - Present a detailed discussion of how the model was built in AnyLogic, describe the assumptions made in the simulation, explain the attributes and input data sources used in the model, and define performance/productivity measures

3. Simulation results - Analyse and compare the results obtained from the simulation experiments conducted in AnyLogic. Make use of graphs and charts to present the different outcomes and also comment on the results.

4. Experimentation - Perform optimisation and parameter variation experiments using AnyLogic's built-in tool to find the optimal solutions for maximising the shop floor throughput. Also, simulate, test, and analyse the top three solutions that improve factory

5. Discussion, conclusions & overall presentation - Summarise the findings and insights from the simulation and optimization experiments. Draw conclusions and discuss their implications for the paper plane production process. Ensure that the report is well-structured, coherent, and presents the information in a clear and organised manner, adhering to the word count requirement.