Mazda unveils new flexible production system for EVs

HOFU, Japan — Mazda unveiled a host of new manufacturing technologies that will slash costs, cut lead times for new vehicles and enable flexible production of electrified cars, as the low-volume Japanese player gears up for battle in an increasingly cutthroat auto industry.

The production upgrades at the Hofu H2 assembly plant here in western Japan will underpin upcoming production of fresh offerings on a newly developed large-vehicle platform as well as a range of EVs that use batteries and motors instead of combustion engines.

The new manufacturing techniques also preview some of the flexible production methods Mazda will introduce at the new U.S. assembly plant in Alabama that it will jointly operate with Toyota Motor. Toyota began producing the Corolla Cross compact crossover at the Huntsville factory last month; Mazda is expected to also build a crossover there.

"We are now in a time when vehicle structure is changing quite rapidly," said Takeshi Mukai, Mazda's senior managing executive officer for global production, purchasing and logistics. "We want to find a good way to run flexibly. … We have taken flexible production to the next level."

Mazda's manufacturing push underscores the urgency of change confronting the small-size manufacturer, long known for its devotion to internal combustion. As competitors rush into EVs, Mazda is counting on its lean manufacturing prowess to engineer a path to efficiently manufacturing electrified and internal combustion vehicles on the same line.

In Japan, Mazda overhauled its Hofu H2 plant in August to shorten the production line, slim down the number of production processes and make room for a new battery subassembly line for electrified vehicles. The upgrades were completed Sept. 1 and unveiled publicly Oct. 6.

The new techniques enable an 80 percent reduction in the time Mazda needs to retool a line for a new-vehicle launch. And they cut the cost of that investment by 90 percent.

Key to the breakthrough is a new conveyor technology called the Traverse Dolly Line.

Instead of using fixed conveyors rooted in pits or hangers that dangle from lines along the ceilings, the new technique uses flat palette platforms that skate along dolly rollers.

The platforms are big enough to support the whole vehicle and have floors flush with their surroundings. Workers can easily walk about the cars and work on them from any angle without having to dodge hangers or step over conveyors. The palettes also can be crammed together closer in the line, meaning that work processes can be combined and the line length trimmed.

When the platform comes to the end of a line and needs to do a U-turn, the palette simply slides to the side along the dolly. There is no need for costly robots to transfer the car, and the system allows Mazda to extend a line by just adding sections of rollers when demand increases.

Where it used to take Mazda six weeks to extend a line, it can now be done in only seven days.

The new dolly system improves overall final assembly productivity by 25 percent, Mazda said.

"The key word here is rootless. It's not non-fixed facility," said Hironori Okano, general manager of the Hofu plant. "In the future, we will be able to do many things flexibly."

Before, only about 15 percent of the factory's main line had such "rootless" processes. Now, after the introduction of traverse dolly technology, about 60 percent of the line is non-fixed.

Another advantage is that it allows flexibility for making EVs on the same line as those with internal combustion engines. Before, a fixed line would lift engines, suspensions or transmissions into a vehicle's bodies at set spacings. Now, those component systems are delivered to the line by fleets of automatic guided vehicles, or AGVs.

The AGVs zoom up under the vehicle body and align themselves perfectly for whatever kind of vehicle they are trying to build — with one AGV handling the front, another AGV the back.

This allows Mazda to flexibly accommodate any combination of long or short vehicles on the same line, with any number of powertrain variants, including all-electric, all-wheel-drive, hybrid and even a newly developed longitudinally mounted transmission for rear-wheel drive vehicles.

Mazda wants EVs to account for a quarter of the Japanese carmaker's global sales by 2030. And by that time, the rest of Mazda's production portfolio will also employ some other form of drivetrain electrification, from mild hybrid to plug-in hybrid technology.