IWATA, Japan—Yamaha Motor Co.’s flagship factory here is using state-of-the-art automated guided vehicles (AGVs) that address the challenges of assembling motorcycles in a high-mix, low-volume environment.
The AGVs can be linked together to form an assembly line or they can disconnect from the line and move to the next assembly process on their own. Called the AGV Bypass Method, the innovative production method replaces traditional conveyors.
The flexible assembly plant builds 35 motorcycle and scooter models with 1,525 variations that are shipped to 94 countries around the world. To enable more efficient production, the factory was recently renovated to increase the number of models that can be produced on one assembly line from 15 models in one category to 17 models across three categories.
Every day, approximately 9,000 different types of parts go into assembling various products at the factory, with some 600,000 parts being used every day.
“Because of fluctuating demand, the difficulty posed by efficiently producing various kinds of products in small lots has been a challenge for us for quite some time,” says a Yamaha engineer who worked on the project. “If we were always producing a set volume of the same thing every day, we could use simpler equipment and production setups.
“However, this creates an inefficient situation in which you have one line operating at full capacity day and night, while the adjacent line lies idle. For example, when we’re running several models on a line at the same time, the number of parts to fit and work time required for each process naturally differs.
“So, an AGV carrying a model that doesn’t require the next process on a line will branch off from it and automatically head over to where its next required process is and merge in. We decided to call this the ‘bypass method,’ because it works just like a bypass, allowing you to avoid a frequently packed road in order to get to your destination faster.”
The AGVs move through the factory not only carrying bikes being assembled, but also information about each product, process and operator. The unit sends assembly instructions to the tools and equipment at each destination, and optimizes the height of the lift to suit the height of the operator and the work process. In addition, the machines have the adaptability and versatility to respond to sudden production requests for just one unit.
