Some unions are discussing their own strategies for contending with a robot-clogged future. “It’s something our union and many unions are still studying,” said Ian Lewis, research director for Unite Here Local 2, a union that represents hotel, food service, restaurant and laundry workers in San Francisco and San Mateo, Calif. “We’re absolutely concerned and trying to grapple with it.”

Whatever their effect on employment, new robots are on the way. Mr. Sekar, an inventor with a doctorate in electronics and computer engineering, said he came up with the idea of building a kitchen robot while working as director of engineering for a semiconductor company. Although he loved cooking at home, he said he craved a way of reducing the work involved.

“I was spending 90 percent of my time doing something sadly repetitive, like chopping ingredients or stirring,” Mr. Sekar said. He wanted to automate those tasks, much as vacuuming can be delegated to Roomba, iRobot’s robotic vacuum. Soon, he switched his focus to food-service robots for restaurants and offices.

Mr. Sekar said his robot has the potential to save money for small businesses that install it in office kitchens alongside appliances like coffee machines. Walking a couple of minutes within a building to a salad-tossing robot instead of venturing outside for lunch would mean shorter work breaks and increased productivity, he said. He calls Sally “the smallest and most affordable cafeteria an office can have.”

The robot is being tested in the office of the Redwood City, Calif., technology incubator GSVlabs and at Calafia Café and Market A Go-Go, a restaurant in Palo Alto, Calif., with an attached market owned by Charlie Ayers, who is the Chowbotics executive chef.