Lights-out manufacturing: what happens when a factory never sleeps?

At the foot of Mount Fuji, in the village of Oshino, FANUC builds robots, servo motors and machine controls. The company's own profile says the campus has achieved "long hours of continuous unmanned machining". A 2003 report in Business 2.0 went further: robots building about 50 robots per 24-hour shift, and running unsupervised for up to 30 days.

In July 2024 Xiaomi's founder, Lei Jun, opened a phone plant in Beijing's Changping district. It cost 2.4 billion yuan, about US$330 million, and its 11 lines are built to make 10 million flagship phones a year. Lei Jun said all of the main processes are automated, though New Atlas reported a small team still working in the control room.

The older case is Philips in Drachten, in the Netherlands. In 2012 the New York Times counted 128 robot arms assembling shavers there, three shifts a day, every day of the year. The plant had several dozen people per shift, about a tenth of its sister plant in Zhuhai, China.

01What does lights-out manufacturing mean on a real shop floor?

Very few plants are dark from end to end. The common version is partial: a cell runs unattended through the night or over a weekend, and people do the setups, changeovers and checks by day. Some engineers call this lights-sparse. For an Indian plant it is the version worth planning for now.

03What has to be true before you switch off the lights?

A machine left alone at night needs four things a person would otherwise do.

• Material arrives by itself. A bar feeder, a pallet changer or a cobot loading blanks keeps the machine fed. One that runs dry at midnight makes nothing until morning.
• The machine checks its own work. Probing inside the machine, or a camera, catches a part drifting out of size. Without it, the morning shift opens a bin of scrap.
• Trouble reaches someone. Sensors on vibration, temperature and tool wear send an alert to an engineer's phone, and the machine stops itself safely.
• The job is steady. Long runs of a part the plant knows well. A new part, a short batch or a fussy material belongs on the day shift.

The same sensors make maintenance predictable. McKinsey's 2017 study of manufacturing analytics put the typical cut in machine downtime from predictive maintenance at 30 to 50%. That describes programmes that already work well, so expect less from a first pilot.

05What happens to the jobs when the lights go off?

A dark line needs fewer people for each part it makes, as Drachten's staffing shows. A vendor who says automation never costs a job is not counting.

For most Indian plants, though, the first unattended night replaces nobody, because that shift never existed. The case changes for a plant already running three manned shifts. Automating the third replaces people, and an owner should tell the workforce so plainly.

For most Indian plants, though, the first unattended night replaces nobody, because that shift never existed.

The work that remains moves up: setting machines, programming, maintenance and quality checks. MeitY's draft robotics strategy plans for retraining workers "displaced due to the rise of automation". The other half of the lesson, keeping people where judgement matters, is in what Toyota, Tesla and BMW teach about automation.