Karakuri Kaizen: The Step Before Industry 4.0
1. Karakuri Kaizen: Introduction and Definition
Increasing the automation level of the production flows with low cost automated equipment is and will remain an challenge to ensure: (1) capacity increase, (2) processes with reliable and avoiding defects equipment, (3 ) short set-up times, (4) the use of standard times for processes and manual operations, (5) the reduction of the operators cycle by reducing the activities for the basic and especially auxiliary functions, etc.
This low-cost automation is within the scope of Karakuri Kaizen. Karakuri Kaizen is a concept inspired by Karakuri Puppet. Karakuri Puppet are traditional Japanese mechanized puppets or automata, originally made from the 17th century to 19th century. According to the Kōjien dictionary, the definition of Karakuri is as follows:”Karakuri [means of manipulating] (from the conjunctive form of the verb karakuru) 1. a device made to move through the manipulation of strings. By extension, a device or contrivance. 2. a plot. 3. Synonym of Karakuri ningyō – a doll which achieves movement through the use of a wind-up clockwork mechanism.”
Coming back to Karakuri Kaizen, these are improvement projects that focus on the development of mechanical devices that use gravity to improve the production system (so they are no electrical, pneumatic or hydraulic devices; they are not connected to computers or elements of the Industry 4.0 paradigm).
2. Positioning Karakuri Kaizen within the Logic of Improvements
Increasing the automation level is in the area of improvements, sometimes more radical/ systemic, more expensive (Kaikaku, including projects for implementing Industry 4.0), sometimes more radical and less expensive (using Methods Design Concept – MDC) or sometimes in the area of systematic improvements and less expensive – Karakuri Kaizen.
Increasing the automation level through Karakuri Kaizen is the next step after systematic improvements or KAIZEN projects (small incremental improvements) projects, which are often focused on ECRS (stands for Eliminate, Combine, Rearrange and Simplify and is an industrial engineering process analysis method – also used by MDC).
Therefore, Karakuri Kaizen development and implementation is usually the before phase of Industry 4.0. As already known, Industry 4.0 aims to increase the automation level of production flows with automation equipment that have quite high costs and involves all types of complex transformations, not just mechanical ones as in the case of Karakuri Kaizen.
From the perspective of the Manufacturing Cost Policy Deployment (MCPD) transformation paradigm, as with any Kaizen or Kaikaku project for Manufacturing Cost Improvement (MCI), all Karakuri Kaizen must be effective and feasible and contribute to the achievement of manufacturing target profit. However, beyond the profitability thinking, companies often develop Karakuri Kaizen projects to support eco-industrial strategies.
3. Karakuri Kaizen Development
Running Karakuri Kaizen projects that are both effective and efficient is an engineering and economic challenge for many professional teams from different companies. I will describe how to think about Karakuri Kaizen projects based on my personal experiences from different projects coordinated by me, projects that were part of the transformation of companies with the help of MCPD.
Therefore, like any kaizen project for MCI, Karakuri Kaizen projects are derived from the Critical to Annual Manufacturing Profitability Tree (CAMPT) and aims at designing and manufacturing new innovative devices or technical/ mechanical solutions necessary to meet the demand volumes of certain products, to reduce workmanship, to eliminate breakdowns and defects. Therefore, after establishing the connection of each Karakuri Kaizen with KPIs related to Cost of Losses and Waste (CLW), one proceeds to understanding of the theme, more precisely, establishing the equipment/ line/ process of the karakuri kaizen project, understanding the reason for choosing Karakuri (charts, trends, etc) and establishing the type of device – getting into the process, in process or after the process. After understanding the topic of developing innovative technical solutions integrated into a Karakuri Device, it is necessary to establish the Karakuri Kaizen team. This team is from any area of the factory (the team is multifunctional; such as: industrial engineering, tools design, maintenance, automation, etc.). First, the team must understand the basic objective of the future technical solution, the future parameters of the Karakuri Device, understand the phenomenon needed to be addressed (examine current and past data for the process of opportunity analysis of Karakuri Device development) and the time required for Karakuri Device completion and then it is decided exactly what data are needed to be collected and analysed for Karakuri Device development.
After the team is already formed and it fully understands the objective of the Karakuri Kaizen project, an activity plan for each team member is established, more precisely a detailed activity plan on team members (who will do what, what will he do, when will he do it?), the plan will also include the schedule of team meetings, estimation of time on intercorrelated activities, drawing the activity diagram and at the same time, the team sets the detailed targets for the future Karakuri Device, converging targets to the annual and multiannual CLW targets, an activity that requires great attention and designing Karakuri Device.
Therefore, targets are set for:
- business needs and productivity needed (Cycle Time/Takt Time for Karakuri Device; effectiveness of Karakuri Device or OEE as % – reliability; the required setup time – flexibility; target for workers vs. automation level);
- defining the basic and auxiliary functions of the Karakuri Device; based on understanding the necessary principles and parameters (as detailed as possible and handwritten): drawings of mechanisms/parts/distances/weights/boxes; description of the principles and operating parameters of weight transfer and transfer times; description of the steps for the future process of Karakuri Device; list of parts that should be involved in Karakuri Device processes; describe the kinematic chain (process) of which the mechanism of the future Karakuri Device will be a part, this will help to determine as accurately as possible the conditions under which the phenomenon needed to be improved;
- Karakuri Device drawing and list of component materials – characteristics and tolerances for assemblies, subassemblies and parts; for the quality level of the materials;
- space available at the shop floor level – the capacity and functioning of neighboring processes and activities should not be affected;
- technological process tolerances of Karakuri Device (Capability Cmk);
- scrap rate target as % (quality; if applicable);
- investment cost and running cost (consumables costs): life-cycle cost analysis (LCCA);
- estimating the maintenance costs of the future Karakuri Device (maintainability); Spare Part/ Service Availability;
- amortization period of Karakuri Device;
- time to manufacturing or the completion time for Karakuri Device which must be synchronized with the target production capacity of the entire system where the Karakuri Device is integrated; Dry Run Tests; Infrastructure compatible;
- safety rules in operation – safety (operability; if applicable); Ergonomics and Hygiene, etc.
After setting the targets, drawing and material lists, make or buy analysis is done for Karakuri Device. Then, after implementing the Karakuri Device, checking the results and benefits is done (Karakuri Device Capacity; Karakuri Device Capability and if any changes regarding Karakuri Device are required). Then a plan for observing and collecting data for the future Karakuri Device is developed. Each target of the designed parameters of the Karakuri Device will be checked in time. The profitability of Karakuri Device is verified after 6-12-24 months. The last step is standardization and extension of improvement, more precisely: SOP implementation, extension of the improvement to other processes/similar mechanisms; visually mark the improvement of Karakuri Device at shop floor level and of course congratulating the team.
4. Expected Results
Therefore, the basic expected outcome of Karakuri Device is the increase of the level of innovative automation of the production flows with automation equipment that have low costs, benefiting from the accumulated experience at the shop floor level to make the work easier, faster and better quality. Always in the MCPD paradigm each Karakuri Kaizen project or CLW means must be convergent to CLW targets further on convergent to annual and multiannual manufacturing target profit. If possible, where possible, using Karakuri Kaizen seeks to delay the application of the elements of Industry 4.0, which are often more expensive and more complex.