Cava used Raspberry Pi sensors to redesign menu boards, seating and grilling

A 2017 Fast Company piece by Ben Paynter says Cava, a Mediterranean fast-casual chain, had grown to 24 restaurants with 18 more planned that year. Chief data scientist Josh Patchus ran a system of Raspberry Pi sensors in select restaurants to monitor everything from customer wait times to food-safety practices.

Motion sensors showed lines bunched near the menu board and while guests chose ingredients at the serving station. Rather than cut choices, Patchus redesigned the menu boards so people knew what to expect when they reached the station; the article says lines moved 10 percent faster and held 12 percent more people. Seating sensors showed urban guests left right after eating while suburban guests lingered, so he suggested 30 percent more seating at suburban sites, and the article says the redesigned stores gained 20 percent more revenue per square foot.

In back-of-house, walk-in refrigerators reported how long they had been open and any temperature or humidity spikes. Data showed the burners heated unevenly, so the prep team cooked items such as the lamb meatballs from the center of the grill outward. Fast Company reports food-quality complaints dropped 28 percent after that.

Long lines put customers off, and sensors showed where they actually formed.

Customers in the suburbs and the city use the same restaurant very differently.

Unseen kitchen faults, such as a fridge left open, are visible only to a sensor.

A Raspberry Pi system is cheap enough to install in a handful of test restaurants.

Cheap sensing in a few pilot sites can turn a vague 'experience' goal into specific changes with measurable returns.

The article reports the figures above and says Patchus used them to boost Cava's 'ROI of experience'. All numbers are as reported by the magazine from the company's data lead, and no independent measurement is given.