• McDonald's, Subway, and Panera Bread recently unveiled new takeout and drive-thru tech.

• They join a slew of chains adding tech to help with labor shortages and digital orders.

• Here are 13 chains adding voice bots, robotic fry cooks, and mobile-order express lanes.

McDonald's and Subway recently unveiled new contactless technology for takeout and drive-thru orders.

The nation's two largest fast food chains in terms of locations are joining a fray of restaurant companies betting big on innovation that involves faster service and fewer humans amid an ongoing labor shortage.

Chipotle, Domino's, and Checkers & Rally's are using AI-powered voice bots to take orders, while fast-casual chains like Sweetgreen are adding drive-thru lanes designated for faster pickup of digital orders.

Fast-tracking automation comes as the labor outlook continues to look grim for the industry. On Friday, new Labor Department data shows that the restaurant industry is still short 400,000 workers compared to pre-pandemic levels.

Here's a look at the 13 chains and restaurant companies adding tech to augment labor and speed up service for digital customers.

Chipotle opened its first Chipotlane in 2018. The new format store has a drive-thru lane dedicated to mobile pickup orders. It was designed to increase the speed of pickup orders for consumers and delivery drivers. Soon chains across the US began to copy Chipotle.

The Chipotlane restaurant became a money-maker, demonstrating "higher volumes and greater returns" than a traditional store, Chipotle said in September when it opened its 500th restaurant with a mobile drive-thru lane. Next year, the chain said 80% of its planned 255 to 285 new restaurants will have Chipotlanes.

In mid-November, the fast-casual chain Sweetgreen opened its first restaurant with a drive-thru pick-up lane. The salad chain is calling the new design feature a Sweetlane.

In June, Chick-fil-A said it began testing a drive-thru express experience for customers. Restaurants with express lanes allow mobile app customers to bypass the traditional drive-thru line to pick up their meals.