Posted on June 20, 2016

Whether in a sawmill or a planer mill an optimizer simulator can be an efficient tool when it’s being used properly. However, it’s important to understand the principles of a simulator before it can become useful.

Successful simulations can be achieved by answering the following questions:

• What does a simulator actually do?
• What is the goal of a simulation?
• What are the steps of performing a simulation?
• Will optimizer parameter changes impact the quality of the sorted products?

What does a simulator actually do?

Wikipedia sums it up pretty well by saying that “a simulation is the imitation of the operation of a real-world system over time”. So basically the simulator is a version of the optimizer (system) that can be used to reproduce tallied results (imitation) from a specific sample of logs or boards. Since the optimizer and simulator are virtually the same, a successful baseline can be established (i.e. if we record 1,000 optimized pieces from production and simulate these same pieces with the same parameters, the results should be identical). With this baseline it is then possible to modify the simulator parameters to achieve the desired results.

What is the goal of a simulation?

The goal of a simulation lays the groundwork for the process and must be defined before starting the simulation. The goal must be based on measurable and recorded performance statistics of the optimizer reporting (i.e. grade distribution, trim loss, product inventory, etc.).

The following are two examples of simulation goals:

Example 1. Increase the percentage of No.2 grade products produced by 1%.

Example 2. Reduce the trim loss by 0.5%.

What are the steps of performing a simulation?

Before the steps are outlined it is important to mention that the user conducting the simulations must have sufficient training with the optimizer user interface. Autolog recommends that simulations and optimizer parameter changes should ONLY be conducted by qualified staff.

For remote or onsite training please contact Autolog’s service department for scheduling (Phone #: 1-450-434-8389).

1. Set a goal for the simulation.
2. Make sure the initial simulator parameters are identical to the production parameters in the optimizer.
3. Select a simulation run as the location to save optimizer board data. Rename the selected simulation run to keep things organized (i.e. Trim Loss Analysis 2016/05/30).
4. Save pieces to the selected simulation run. Use the recording feature of the optimizer to automatically save pieces and use the filter function to select the desired products (i.e. you could filter for a specific product/grade/dimension or just take a random sample of production).
5. Simulate the saved pieces using the same parameters as the optimizer to create the baseline. With the Autolog optimizer a test report can be created as the pieces are being saved to the simulation run and can be used as the baseline.
6. Modify simulation parameters and re-simulate. Continue until desired results are achieved. Make sure to keep track of all the parameter modification.
7. Backup the current optimizer parameters.
8. Adjust the optimizer parameters based on the analysis in the simulation.
9. Monitor production to make sure the changes have not had adverse effects on the production outcomes. If the results in production are not satisfactory, roll back to the original set of optimizer parameters and begin a new simulation analysis to try and meet the stated goal.

Will optimizer parameter changes impact the quality of the sorted products?

YES. If you loosen the optimizer parameters, then the overall quality of sorted products will be reduced (i.e. to reduce trim loss, then more defects will have to be accepted in the sorted products). To increase the quality of the sorted products, then the optimizer parameters will have to be tightened (i.e. to increase sorted products, quality optimizer parameters will have to be tightened and trim loss will go up).

The next step is to put this guidance into practice. The more time spent using the simulator and the user interface, the more comfortable it will become.

The team at Autolog is always available for assistance.

Billy – Process Expert