Checkpoints
Checkpoints, in the military, are used to track progress of a unit’s movement.
In Lean, checkpoints can be used in a similar fashion. Checkpoints can be linked to specific process steps. When the sequence of work is standardized, the operator should hit those checkpoints with the same time remaining in the takt time each and every cycle.
Simply put, if an operator knows that at Step 3 (her checkpoint), she should have 3:08 left on the countdown clock, and she only has 2:07, she is behind. If it reads 4:11, she is ahead. Both situations indicate a problem of some sort.
Hitting checkpoints with too little time left means a potential line stop. The operator should call for help.
Hitting checkpoints with too much time left normally indicates a missed step. The operator should check her work.
2 Comments
RISA60 · January 12, 2013 at 8:15 am
Would you advocate countdown clocks on each station as having a positive influence on Operator performance? Have not tried those. have an overall target indicator for the line at one point only.
Jeff Hajek · January 12, 2013 at 8:30 am
It is not a direct impact on performance, but rather it enables both short term help and long term improvement. If an operator falls off the pace, he or she can recognize it early and call for help. If they trust that the cavalry will come charging in, they will require less buffer time in the process because they know the responder will help get the work back on track. It also spreads out the demand on the support team. Typically, everyone waits until the end of a process to call for help. With checkpoints, the floater/supervisor can help throughout the cycle, so there are fewer line stops.
As for long-term, it is easier to identify where the problem is when the response is immediate. Root cause analysis and problem solving takes less effort, speeding up the pace of improvement.