Implementation of a simple electronic/software Andon system to be used in a production company (factory) to communicate and visualize problems occurring at workstations or production lines.
Note: [This repository has been superseded by a new version of the Andon application, which can be found at https://github.com/vitplanocka/eAndon-MVC # eAndon. Please refer to the new repository for the latest updates and features.]
The program can be configured to display a range of different problems (technical issues, quality issues, material supply issues, …) and can be also configured to display various configurations of workstations and display screens. The program runs on Windows OS and can be used in a situation where there are computer terminals near the production workstations on the shopfloor that can be used to trigger alarms when problems occur at the workstations.
Andon is a popular tool used in Lean Manufacturing. It was originally pioneered by Toyota as a method to visualize problems, help create employee's awareness about targets and non-standard conditions, and promote leadership behavior. It is linked with the Jidōka methodology in the Toyota Production system that encourages operators to recognize a deviation from the standard and stop work and call supervisors or support staff who can help solve the deviation. Most Japanese factories display a variation on the sign「止める・呼ぶ・待つ」- Stop-Call-Wait that reminds operators that this is the expected behavior.
Originally, the operator would pull the Andon Cord, which was a rope located above the line, but Andon can take many forms. It can be activated by an operator pulling a cord or pushing a button, or it can be automatically activated by equipment when a problem is detected.
Whether used because of part shortage, equipment malfunction, or a safety concern, the point of Andon in Lean manufacturing is to stop work so that the team can gather together, perform a real-time root cause analysis, and quickly apply a solution. Once the problem is resolved and work continues, the occurrence is logged as part of a continuous improvement system.
Electronic/software Andon
Most modern production facilities implement some kind of computer terminals on the shop floor to record the production data, allow the operators to access the working instructions, etc. Such terminals can also be used effectively to run an Andon software so that it is not necessary to use physical systems (e.g. an Andon Cord or specialized industrial solutions consisting of custom electronics with buttons and visual displays). The advantage of the electronic/software system is the cost (in case terminals and display screens already exist on the shop floor, they can be used to run also the software Andon) and flexibility - new types of alarms or new workstations can be added quickly without additional costs.
Diagram of the eAndon
The illustration below shows a typical setup where there are several networked terminals (each running a separate Andon terminal application), each terminal handles one or more workstations. There is one or more dashboards (TV display in a production hall, laptop computer used by factory staff, …) that display the total shop floor overview.
- Features of the system
- Allows operator to trigger a number of different alarms (the software allows from 1 – 10 alarm types)
- Alarms are displayed on one or more dashboard which can be placed in communal areas (e.g. TV placed on the shopfloor visible to all) or dedicated team areas (e.g. maintenance team’s workshop)
- Alarms are displayed in a way to give to Production management a quick overview about the status of the production process
- Priority (bottleneck) lines are highlighted on the dashboards, allowing prioritization of the actions
- With every alarm, the duration of the alarm is displayed and logged, creating a psychological nudge to solve the abnormal situation as soon as possible
- Clicking the workstation number opens a window showing the history of alarms and their durations
- Info text field displayed on both the dashboard and the terminal programs allows to communicate to operators and support personnel current production targets and results or other important information
- The number of terminals and dashboards used by the software is not limited. The number of workstations displayed in software is limited only by the space available on the dashboard screens (up to ~60 workstations can be displayed)
- The assignment of the workstations to the terminals is defined in a text file. In case that the arrangement of the workstations or terminals changes (e.g. a new workstation is added or a workstation is assigned to a different terminal), this can be easily changed in a text file and is immediately reflected by the terminal programs
- Labels and text in the software is included in a text file, can be easily translated to a local language and is immediately reflected in the terminal and dashboard programs
- Limitations of the system
- All alarms must be entered into the program manually by operators or supervisors, the software does not currently support automatic communication with machines on the workstations
- Software only works in Windows OS
The binaries provided in the release section come with a preconfigured setup that includes:
- Andon_dashboard.exe - dashboard showing the overview of the status of the workstations
- Terminal01.exe ~ 04.exe - four input programs to be run at four networked terminals, each allowing to start an alert for one or more workstations linked to the terminal
In order to customize the setup for the specific use case, edit the following configuration files:
- Assets/settings.txt - in this main configuration file, specify the following variables
- Number of alarm types to display in columns in grid view - this controls how many columns of alarm will be displayed (default is 5, maximum is 10). Based on the number of alarm types, there should be corresponding icons Icon1.png ~ Icon10.png available in the /Assets folder
- Image file for company logo - filename for logo in the /Assets folder - put the logo you want to use in the /Assets folder
- Alarm sound file - filename for the sound played when an alarm is triggered
- Instructions - text displayed in the input programs describing their usage
- Alarm label # - text displayed above the icon for the alarm type #
- Assets/Workstations_terminals.txt - this configuration file specifies the arrangement of terminals and workstations
- on the first line, the total number of workstations is entered
- second line describes the format of the subsequent lines
- from the third line, a description of each workstation is given: sequential number starting from 0, workstation number, workstation name and terminal that controls the workstation (should always be called terminal01 ~ 04)
- priority_workstations.txt - this file specifies which workstations should be highlighted in the Andon_dashboard screen. Workstation numbers to be highlighted are entered on separate lines
In case you need to set up different arrangement then 1 dashboard and 4 terminal applications, rebuild the program from the source, adding or removing the terminal programs as needed. Each terminal is a separate project, the code of each is the same.
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Start with applications Andon_dashboard.exe, Terminal01.exe ~ 04.exe, file priority_workstations.txt and sub-folders /Assets, /Data and /Logs in one folder to which the terminals have read/write access and the computer displaying Andon_dashboard has at least read access.
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On each terminal, run the appropriate Terminal0#.exe file. On the computer(s) displaying the visualization, run the Andon_dashboard.exe file.
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When alarm occurs on some workstation, on the relevant terminal click the green field in Terminal0#.exe corresponding to the workstation and type of alarm. The green field will turn yellow or red (based on settings) and the field will start to show a counter with amount of minutes since the alarm was triggered.
The same information will be displayed immediately on the Andon_dashboard visualization.
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When the alarm at the workstation is resolved, click again the field in Terminal0#.exe so that the status of the alarm returns to green.
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Logs of the triggered alarms are saved in the /Logs folder in the alarmlog_terminal0#.txt files.
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History of the alarms can be displayed in a separate window by clicking the workstation number.
- Both the dashboard and the terminal programs have an information text box that can be used to display current information for operators (e.g. the target and result from previous day and plan for the current production day). The text displayed in this text box is read out from the text file InfoTextForOperators.rtf where it can be manually or automatically adjusted as needed.
This project is licensed under the MIT license
Vit Planocka
Email: [email protected]
Location: Prague, Czechia
GitHub: https://github.com/vitplanocka
LinkedIn: https://www.linkedin.com/in/vitplanocka/