The operations pages are intended for the floor supervisor. These pages display information about the past few days of cell operation and allow the supervisor to keep the cell operating smoothly. (Anything older than a couple days should not be analyzed on the shop floor the heat of the moment but instead be addressed in a monthly review.)
We suggest that the operations dashboard is bookmarked by the supervisor and visited directly. There are also tabs for monitoring the operators at the load station, the machine cycle times, and all the material in the system.
The dashboard shows an overview of the current status of the cell. The supervisor should keep the dashboard open since it allows at a quick glance to understand if the cell is running well.
On the left is a bullet chart showing the current jobs with their completed count and remaining machining time. On the right is an overview of the stations, showing the OEE for the past week and information about the pallet at each station (if any).
The bullet chart on the left shows the current progress of the jobs in the
cell controller. Each process of each job receives one row and the x-axis is
machine hours. A black tick mark is placed at the expected machining hours
for the entire job. For example, if the job for part
zzz has a total
quantity of 22 parts and the expected machine cycle time is 77 minutes, the
expected total time for the job is
22 * 77 = 1694 minutes ~ 28.2 hours so a
black tick mark will be placed at 28.2 hours (see the bottom row in the
As parts are completed, a brown bar is filled in with the credited machine
hours for the completed parts. For example, if the job for part
completed 17 parts, then the credited machine hours is 17 times 77 minutes
which is about 21.8 hours so a brown bar will be drawn up to 21.8 hours (see
the bottom row in the screenshot above). A completed part is credited only with
its expected cycle time even if the actual time on the machine is larger. Also,
a completed part is assigned only once the part has been completely machined and unloaded.
Indeed, the bullet chart does not reflect in-process or partially machined material, because
the program might not finish correctly or the part might be become scrap.
The bullet chart is an easy way to watch the progress on the current jobs. If a job is created for each day, the chart can be used to estimate the current day's progress (keeping in mind that in-process material is not visible on the chart).
On the right of the dashboard, there is one circle for each machine and load station in the cell.
The outside of the station is a circular gauge displaying the operating equipment effectiveness (OEE)
for the past week. This is calculated by taking all cycles from the past
7 * 24 = 168 hours, adding up
their expected machine or load time, and dividing by 168 hours to obtain a percentage. This percentage is used
to fill in the gauge on the outside of the station, and can also be viewed in a tooltip by mousing over the station.
In addition, each station shows the pallet currently at the station (if any) and when moused over the tooltip will display additional information about the material on the pallet, including the program currently in execution, expected remaining time, or parts being loaded. More details about the current material on the various pallets is available in the Material tab.
The Load/Unload tab allows the supervisor to monitor the operators at the load station.
First, there is a table which shows cycles from the last three days which are statistical outliers. The outlier detection is based on the median absolute deviation of the median, which is more resiliant to outliers than the standard deviation. There are two reasons that a load/unload cycle will appear here:
- If the actual time at the load station is far away from the median actual time, the cycle will be displayed. Cycles of this type indicate that the load operation took longer than expected.
- If the expected load time from the job is far away from the median actual time, the cycle will be displayed. Cycles of this type indicate that the expected time is unrealistic (as long as enough cycles are available to obtain good stastitics). In this case, the expected load time in the flexibility plan should be adjusted to be equal to the median time. Alternativly, perhaps the steps or procedures at the load station should be changed.
Next, the planned and actual load hours for the past 7 days are shown. The data can be toggled between a bar chart and a table. Anything older than 7 days is available as part of the monthly review on the flexibility analysis page.
Finally, the page contains a chart of all load station cycles from the past 3 days. The chart can be zoomed by clicking and dragging, filtered to specific parts and/or pallets, and toggled to a table. Clicking on any point allows more details about the cycle to be loaded. Again, anything older than 3 days is available as part of the monthly review on the flexibility analysis page.
The Machines tab allows the supervisor to monitor the performance of the machines. It displays identical data as the Load/Unload tab but for machines instead. First, there are outlier cycles from the last three days based on the median absolute deviation of the median. Next, the planned and actual machine hours for the past 7 days, and finally a zoomable and filterable chart of recent machine cycles.
The Schedules tab shows the supervisor an overview of the scheduled and actual parts produced in the past 7 days. The table lists all the jobs downloaded from the past seven days together with the quantities of parts in various stages.
- The Note column allows the user to enter a note for each schedule (does not impact the production in any way, just useful as a comment field).
- The Scheduled column shows the original quantity of parts downloaded into the cell controller as part of the job.
- The Removed column shows the count of planned parts that have been removed from the cell controller by an operator after the job was downloaded.
- The Completed column shows the count of parts that have been logged to be completed.
- The In Process column shows the count of material currently on pallets or inside in-process queues.
- The Remaining To Run column shows the quantity of parts that the cell controller is currently configured to produce.
Note that in an ideal situation these numbers add up properly (scheduled = completed + in-process + remaining), this does not need to be the case. If parts are scrapped, an operator or supervisor edits the schedules in the cell controller, or other unplanned changes are made, the quantity of parts in these columns is updated to reflect the current sitation on the shop floor. Thus, this table can be used to provide an overview of the actual operations as compared to the original planned schedule.
The Material screen displays all virtual whiteboard regions. This includes the regions for all pallets and all configured in-process queues. If quarantined material is enabled (as seen in the screenshot below), material can be moved between the various quarantine queues by clicking and dragging on the vertical dots on the material card. In addition, notes can be added to each piece of material by opening the material card.