> For the complete documentation index, see [llms.txt](https://virtualfactory.gitbook.io/vlft/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://virtualfactory.gitbook.io/vlft/use-cases/jsimio/manufacturing-system/jsim.md).

# Performance evaluation in Jsim

## Assembly Process

## Case Description

| Stage | Technology       | Input                  | Output        | Duration      |
| ----- | ---------------- | ---------------------- | ------------- | ------------- |
| 1     | Adhesive joining | Component1, Component2 | WIP1          | Normal(10, 2) |
| 2     | Spot welding     | WIP1, Component3       | WIP2          | Normal(5, 1)  |
| 3     | Hemming          | WIP2, Component4       | Final product | Normal(2, 1)  |

The assembly process is a combination of three stages: Adhesive joining, Spot welding and hemming. And the Final product is a result of joining the four components: Component 1, Component 2, Component 3 and Component 4 where WIP1 and WIP2 are the intermediary outputs during the process. The table below defines the input, output and processing time of each stage.

​But while modelling the system in JMT, we have eliminated the intermediary outputs WIP 1 and WIP 2. Instead we have assumed Final product to travel throughout the assembly process

## Formal Model

![](/files/-MNzWSqvmVxumWKVmq3r)

![process classify](/files/-MNzWSqwi_ZOJgd_nBge)

## Performance Evaluation

### Modelling of the system

![](/files/-MNzWSqx0vK-MwvsoM5E)

Open **JSIM graph** from the various tools in the home panel of JMT software

![](/files/-MNzWSqyr6dYtchFlmhZ)

1. Select the **source and sink** icons in the toolbar and then place it in the workspace

![](/files/-MNzWSqz2wucoluaPAhF)

Insert machines into the workspace by clicking the **queue** icon in the toolbar

![](/files/-MNzWSr-RPd34EIeDVMI)

Insert Fork and joins into the system by clicking on the above highlighted icons. All the 4 components gets divided at **Fork 1** and they are routed accordingly

#### Customer Classes

![](/files/-MNzWSr09aoYxq_mqNWc)

1. Click on **Add class** button
2. All the components are selected as **open** type
3. Select **fork** as the reference station for the components
4. Select **source** as the reference station for the final product

![](/files/-MNzWSr1G2J1JiLRfQVg)

1. Click on **Edit** button and select **Exponential** in order to record the interarrival time of final product
2. Enter the desired generation rate which is **1 part/second**

#### Fork 1

![](/files/-MNzWSr2PnB7AQkTVoph)

1. Select **Infinite** capacity option under the queue section of Fork 1

![](/files/-MNzWSr3sKWAtW7W7Vq_)

1. Select **Branch probabilities** as the fork strategy for Component 1
2. Enter the probability as 1 for **Join 1** and 0 for other two joins

![](/files/-MNzWSr43IKHIqVlft6a)

1. Select **Branch probabilities** as the fork strategy for Component 2
2. Enter the probability as 1 for **Join 1** and 0 for other two joins.

![](/files/-MNzWSr59K_iBVo1E5eM)

1. Select **Branch probabilities** as the fork strategy for Component 3
2. Enter the probability as 1 for **Join 2** and 0 for other two joins

![](/files/-MNzWSr6MUjkNh30QEVD)

1. Select **Branch probabilities** as the fork strategy for Component 4
2. Enter the probability as 1 for **Join 3** and 0 for other two joins

![](/files/-MNzWSr7qlDZlK9KWsRS)

1. Select **Multi Branch Class Switch** as the fork strategy Final product. Here the final product is modelled throughout the process eliminating the intermediary outputs WIP 1 and WIP 2

#### Join 1

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-join_1_strategies.png)

1. Select **Standard join** as the join strategy for all the components
2. Select **Quorum** as the join strategy for the Final product. Follow the same for all the joins

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-join_1_routing.png)

1. Select **Disabled** option as the routing strategy for the components 3 and 4
2. Select **Probabilities** as routing strategy for the Final product
3. Enter the probability as 1 for **Adhesive joining**

#### Adhesive joining

![](/files/-MNzWSr880DfrGFQmwOJ)

1. Select **Infinite** capacity option under the queue section of Adhesive joining

![](/files/-MNzWSr9ENU03A_8SFAX)

![](/files/-MNzWSrAhpBc1oHQAapI)

1. Select **Disabled** as the strategy for all the components under Service time distributions table
2. Select **Load independent** as the strategy for Final product and click Edit
3. Choose **Normal** distribution
4. Enter 10 as the mean and 2 as the standard deviation value

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-Adhesive_joining_routing.png)

1. Select **Random** option as the routing strategy for the components
2. Select **Probabilities** as routing strategy for the Final product
3. Enter the probability as 1 for **Join 2**

#### Join 2

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-join_2_routing.png)

1. Select **Disabled** option as the routing strategy for the components 1,2 and 4
2. Select **Probabilities** as routing strategy for the Final product
3. Enter the probability as 1 for **Spot welding**

#### Spot welding

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-ss_spot_welding_.png)

1. Select **Disabled** as the strategy for the components
2. Select **Load Independent** as the strategy for Final product. Enter normal(5,1) as the service time

![](/files/-MNzWSrBKhe3utoQ7WMM)

1. Select **Probabilities** as routing strategy for the Final product and **Random** for the components
2. Enter the probability as 1 for **Join 3**

#### Join 3

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-join_3_routing.png)

1. Select **Disabled** option as the routing strategy for the components 1,2 and 3
2. Select **Probabilities** as routing strategy for the Final product
3. Enter the probability as 1 for **Hemming**

#### Hemming

![](https://github.com/frabera/virtualfactorytoolkit/tree/885e2604d12ee12a144917bf450f99a3e27ebfe1/.gitbook/assets/apjs-ss_hemming_.png)

1. Select **Disabled** as the strategy for the components
2. Select **Load Independent** as the strategy for Final product. Select normal distribution and enter 2 as mean and 1 as standard deviation

![](/files/-MNzWSrCUVldR-88fgBw)

1. Select **Probabilities** as routing strategy for the Final product and **Random** for the components
2. Enter the probability as 1 for **Sink**

#### Performance Indices

![](/files/-MNzWSrDlHHtjTqM8JqR)

1. Click on **Select an index** drop down box and choose Throughput per sink and Utilization as indices
2. Select **Final product** as the class and **Sink** as the station
3. Select all the three stations in order to find the utilization

### Simulation results

![](/files/-MNzWSrEZuUBTk0284R4)

Utilization of :

Adhesive joining = 1

Spot welding = 1

Hemming = 1

![](/files/-MNzWSrFyPCnwa0lcWPF)

Throughput of the system = 0.4851