Lights-outmanufacturing is a manufacturing methodology, not a specific process. Factories that employ "lights-out manufacturing" are fully automated and require no human presence on-site. These factories are considered to be able to run "with the lights off." Many factories are capable of lights-out production, but few run exclusively lights-out. Typically, in Computer Numerical Control machining, workers are necessary to set up tombstones that hold parts to be manufactured and remove completed parts. As the technology necessary for total automation becomes increasingly available, many factories are beginning to use lights-out production between shifts to meet increasing production demand or to save money on labor. Going forward this concept of automation will become more popular and can support human beings. An automatic factory is a place where raw materials enter, and finished products leave with little or no human intervention. One of the earliest descriptions of the automatic factory in fiction was the 1955 short story "Autofac," by Philip K. Dick.
CNC machines do not require continuous operator attention, and some models can run unattended. A few machine shops run CNC unattended on nights and weekends. Although the machines are run without being under constant supervision, it is a common practice to always have a person in the vicinity of the machine.
Existing "lights-out factories"
, a Japanese robotics company, has been operating as a lights-out factory since 2001. Robots are building other robots at a rate of about 50 per 24-hour shift and can run unsupervised for as long as 30 days at a time. "Not only is it lights-out," says Fanuc vice president Gary Zywiol, "we turn off the air conditioning and heat too." In the Netherlands, Philips uses lights-out manufacturing to produce electric razors, with 128 robots made by Adept Technology. There are only nine human quality assurance workers who oversee the end of the manufacturing process. In the manufacturing of integrated circuits using 300 mm wafers, the entire manufacturing process is completely automated, with workers only making sure that the process runs without problems and repairing any faulty machinery.
Motivations for lights-out factories
Lights-out manufacturing may increase productivity and lower upkeep costs. Companies incorporating lights-out methodologies into floor plans only need to consider robotic workers, which minimize space and climate-control requirements. Human laborers can be dispatched to a separate location for tasks such as quality assurance. Optimizing manufacturing space for a fully autonomous robotic workforce allows for an increase in productivity. James Cook, an application engineer at Stäubli, colleague of David Arceneaux and the business development and marketing manager at Stäubli Robotics, says robots can help lower building costs by requiring smaller work cells. He states that "manufacturers can fit a larger number of compact cells in the same space to increase production without adding heating, lighting, or cooling to the cost of the building." Floor space is also important for energy conservation, as a smaller space reduces energy consumption by reducing heating costs. Without human workers, climate-control systems are unnecessary, and smaller layouts require less electricity.
Opposite approach
Since the mid-2010s, Toyota has been moving in the opposite direction, replacing robots with human workers because the human is considered to be essential for flexibility and process improvement. Robots are incrementally reintroduced where appropriate.
