Lean principles / Jidoka and andon
Jidoka and andon: stop at the problem, call for help right away
Jidoka is the second pillar of the Toyota Production System: the process stops when something goes wrong, instead of producing defective parts. Andon is the signal that tells everyone where the problem is. Poka-yoke prevents the error before it happens. Here you'll find the physical tools we use to put it into practice.
Why stopping pays off
A hidden problem turns into scrap, rework or a complaint. A problem flagged right away is solved where it starts, with the person who saw it. That's why in TPS anyone can stop the line and ask for help.
Three things are needed: a simple way to call, a status everyone can read from a distance, and mechanical devices that make the most common errors impossible.
How to spot it on the shop floor
Signal 1
The operator waits for material or the shift supervisor with no way to call them.
Signal 2
Problems surface at the end of the shift, in the report, not when they happen.
Signal 3
Recurring errors tackled with "more attention" instead of a device.
01
The call: one button, no cables
Wireless buttons at the workstation to call for material or assistance.
The problem
The operator leaves the workstation to look for the forklift driver or the material.
The solution
LoRa wireless call network for LeanRobot systems, no wiring needed; with PUDU robots, the call brings the material to the workstation.
PUDU Pager kit
10 wireless buttons, gateway, 2 LoRa modules
Call and signaling network with no wired infrastructure, for large sites or changing layouts.
Pudu T300L
Moves the cart
Slides under dedicated racks and carts and drops them off at their destination.
See also: PUDU call and connectivity · Autonomous logistics
02
Status at a glance
Green, yellow, red: the status of every line or area can be read in passing.
The problem
Delays and stoppages discovered in the next day's report.
The solution
Traffic light for Cardplan® boards, red/green magnetic flip symbols and pocket boards to track open issues.
Traffic light system for Cardplan
Red, yellow, green
Corner markers that slip onto the board pockets.
Double-sided magnetic symbols
Red/green
Change the status by flipping them, no writing needed.
Magnetic Windows – Frame
Issue log
Open center for filling in the sheet at the workstation.
See also: Kanban and heijunka boards · Heijunka and visual planning
03
Poka-yoke: making the mistake impossible
Mechanical devices that force the right action.
The problem
Containers picked from the wrong side, carts stopped in the wrong spot, codes mixed up.
The solution
Anti-return stops and singulators on the lanes, Park Stations that fix the cart position, color-coded card holders to tell codes apart.
See also: Karakuri · Supermarket and FIFO
Tools to get started
Which AMR for which load
Jidoka in the TPS house
From problem to standard
Have an industrial project to develop?
Choose where to start. Or call us: +39 0434 572757.
Robot demo at your site
We bring the robot to your shop floor and you see it working on your own routes.
On-site visit
We come to see your shop floor, flows and spaces, and propose the right solution.