The Toyota Production System (TPS) is a manufacturing model that has changed the way production works around the world. TPS originated in Japan at the Toyota Motor Company in the first half of the twentieth century. TPS has become widely known in the West at Lean Manufacturing or just Lean. The Toyota Production System aims to streamline processes and reduce waste in order to increase efficiency and improve productivity. It also focuses on respecting people in the workplace and ultimately pleasing the customer.
To achieve these goals, TPS practitioners focus on the value of the work they do or the products they make. They do this by examining the value stream—the process that creates products from start to finish—to identify areas for improvement. Often, these opportunities for improvement involve what are referred to as the 7 wastes of Lean. These wastes are sometimes called muda, a Japanese word for waste. Other improvement possibilities involve mura (unevenness) and muri (overburden), which can strain people and processes.
The Toyota Production System also involves changing the culture of the workplace so everyone looks for small ways to continually improve processes. This continuous improvement is called kaizen. Many other methods and tools are used in TPS as well including 5S, gemba, kanban, just-in-time, poka yoke, and heijunka. Each of these concepts contributes to making the workplace function effectively.
A series of innovations at Toyota led to the development of TPS as a whole system:
- Starting out in the early 1900s at his textile company, Toyota founder, Sakichi Toyoda, sowed the seeds of automation and the groundwork of TPS when he created textile looms that stopped whenever a thread broke. This method of creating machinery that alerts people to problems automatically frees people up to do other work or oversee more machines. It is a simple way to increase efficiency.
- In the 1930s, Toyota adopted a just-in-time (JIT) production strategy to keep inventory amounts and costs down and to speed up and continually improve the production process. This method of production prevented creating too much of something.
- Toyota looked to line workers and employees on the work floor for suggestions, which led to the creation of the kaizen way. In this work environment, everyone looked for ways to improve tasks.
- Taiichi Ohno, often called the father of the TPS, studied supermarkets in the United States, which helped him realize that production should not be based on sales goals, but on actual sales. This led to the kanban system, which uses visual cues such as cards to tell people when to start producing something (usually when an order is placed by a customer). These cards prevent overproduction.
- Ohno put these methods together into a unified production system, which helped Toyota keep costs down and become an efficient, competitive auto manufacturer.