The Toyota Production System, or TPS, is a widely-used and successful production system in manufacturing that focuses on reducing and eliminating waste, while producing quality products for consumers. The TPS model was developed by the Toyota Motor Corporation for their vehicle production system, but the principles and activities it encompasses can be applied to nearly any industry.
When discussing the TPS and its many features, it can be helpful to think of the system like a house. The “house” of the Toyota Production system is built upon a strong and stable foundation, has two main pillars, with the overarching goal of TPS as the tip of the house.
The pillars of the house are also considered the basis of Lean manufacturing. Turning concepts into practice
The pillars of TPS
The first main pillar is the idea of just-in-time manufacturing. This emphasizes three main practices: continuous flow, Takt time, and a pull system. The idea of JIT manufacturing is to implement a production method that emphasizes the minimization of waste and workers being able to operate efficiently. Instead of producing items as you have the materials, certain steps of the production phase shouldn’t start until an order trigger it.
A pull system, usually a Kanban method, is designed to signal when an action is supposed to happen. Implementing a Kanban system works to keep the factory from overproduction. Certain processes and steps in the manufacturing process will only begin when a worker receives a specific signal. By doing so, unnecessary inventory will not be created, and bottlenecks will be reduced.
Takt time, another strategy used in just-in-time manufacturing, ensures the rate of manufacturing between stations is even. The equation used to calculate Takt time is T = Ta ÷ D. The T represents Takt time, Ta represents the total available production time, and D represents the rate of customer demand. By finding the Takt time, you will know how much time it should take to produce each product in order to meet customer demand.
The second pillar is Jidoka, often referred to as autonomation, meaning automation with human touch or human intelligence. This process essentially refers to the use of machines or equipment to alert workers of a problem with a process before more resources are wasted. TPS focuses largely on building a culture that emphasizes stopping to fix problems as they arise in order to get quality from the start.
A main principle of this is the idea that in the case of abnormalities, machines should stop, and workers should be notified of what went wrong. An example of this is a workplace using Andon lights. Andon lights are most often light posts with a green, yellow, and red that will change color when a problem arises in a manufacturing process. The visual signal will alert employees to an interruption and the issue can be addressed immediately. This uses both the machine detecting errors to alert the worker something needs to be fixed, a perfect example of automation with a human touch.
The pillars of the Toyota Production System are built upon a stable foundation of standardized work and continuous improvement. The goal of using the strategies of Toyota and Lean manufacturing, like Kanban, Takt time, and Andon lights, is to create high quality products at the lowest cost to the manufacturer with the shortest lead time. Eliminating wastes and ensuring the product will meet customers’ expectations are the name of the Lean manufacturing game.