LOS ANGELES, California — Embark, a San Francisco start-up, completed a coast-to-coast test drive of its autonomous semi-truck. It was announced on Tuesday. It drove from Los Angeles to Jacksonville, Florida, in the test drive, covering around 2,400 miles without relying on a human driver on the freeway.

The truck was not hauling cargo. The company is hauling refrigerators on another route from El Paso to LA.

Embark has already integrated its self-driving systems into 5 trucks, according to co-founder and CEO Alex Rodrigues. It doesn’t manufacture its own vehicles, but instead created a self-driving system that can be integrated into Peterbilt, and possibly other vehicles. Embark plans to acquire 40 more semi-trucks within the year for further testing and long-haul deliveries.

Embark uses machine learning software and data from the sensors onboard its trucks to map its surroundings in real-time and avoid obstacles. Others “pre-map” their routes and use data from the sensors onboard to improve their maps.

The “sensor suite” in an Embark truck includes five cameras, three long-range radars and at least two lidars (light detection and ranging sensors).

During the test drive, professional safety drivers were inside, ready to take over the wheel if needed. In the long-term, the start-up aims to produce autonomous trucks that can drive themselves on freeways but would require a human to get on and off the exits, and to navigate around cities or small towns.

This concept would make it possible for truckers to keep their jobs but cover long routes and make more deliveries in less time, Rodrigues said.