Fast food restaurants are using robot chefs because they can't find enough workers

American restaurants are employing robots to make up for a shortage of fast-food workers.

Businesses around the world are increasingly turning to droids to reduce running costs – and fast-food joints are at the forefront of the robot revolution.

Earlier this year, we saw Flippy the burger-flipping robot take up residence in a Californian burger restaurant.

And now US burger chain Wendy's has begun installing self-cleaning ovens in some stores, according to the Wall Street Journal.

Meaty restaurant chain Arby's also uses smart ovens, which can cook roast beef and then switch to a "holding" mode.

This means employees can cook food for the next day the night before, rather than arrive at 7am to starting roasting.

It's an unsurprising response to a severe shortage of fast-food workers across the pond.

"I've never seen the labor market this tight," said Scotty Murphy, COO for Dunkin' Donuts, speaking to the WSJ.

"We spend a lot of time training people and a month later they walk out the door."

The US hospitality industry had 844,000 unfilled positions in April this year – a record high.

The industry accounts for roughly one out of every eight jobs available in America.

Dunkin' Donuts has already automated some processes – like producing expiration labels for food, and measuring the quality of coffee.

"I don't have to be constantly worried about other smaller tasks that were tedious," said Alexandra Guajardo, the morning shift leader at a Dunkin' Donuts store in California:

"I can focus on other things that need my attention in the restaurant."

According to a 2013 study by the University of Oxford, food service jobs ranked among the top 20% most automatable – from 700 occupations surveyed.

And research by the Organization of Economic Co-operation and Development said food preparation faced the highest probability of automation among 88 industries.

"In this market, employees will leave if they have one bad day," Patrick Sugrue, chief exec of Saladworks, told the WSJ.

"If that happens, having this technology in place makes it easier to deal with.

"Having wait times go up due to short staffing is a quick way to kill a brand."

Earlier this year, Flippy the burger-flipping robot started working at CaliBurger in Pasadena, California.

The food prep bot can flip burger patties, and then remove them from the grill when they're ready.

Flippy doesn't look much like a fast-food worker though – he's actually just a giant mechanical arm with joints.

The bot is powered by an AI brain that uses computer vision to identify and monitor burgers.

It can tell the difference between an uncooked patty, a cooked burger, and even a cheese burger.

Flippy also knows what a bun looks like, and can identify the top and bottom buns – as well as the inside and outside of the bun.

Better still, Flippy knows the switch between spatulas when moving between raw meat and cooked meat.

And he can even clean the utensils while cooking, and wipe the surface of the grill with a scraper.

This story originally appeared in The Sun.