According to Fortune.com, TuSimple, which is a China-based startup that is developing driverless commercial trucks, has raised $55 million in a Series C funding round, which was led by Composite Capital, and included contributions from existing investors Sina and ZP Capital.

TuSimple will use the funding for a variety of tasks, including scaling up its testing to two full truck fleets in China and the U.S.

The funds will also be used to hire production engineers in Tucson, Arizona; the location where TuSimple established a test facility back in August. And, some funds will also be put towards the company’s research centers in San Diego, California and Beijing, China.

Founded in 2015 with a focus on “line-haul trucking and transporting cargo between ports, plants, and warehouses,” TuSimple is developing a Level 4 system, which is a designation by the Society of Automotive Engineers (SAE) that means a vehicle can drive itself independently in certain conditions.

Back in July, the Level 4 system was used to complete a 170-mile public road test from San Diego, California to Yuma, Arizona. A few months later in September, testing of the L4 autonomous truck started on public roads in China, and this month, the Level 4 self-driving system was demonstrated in Shanghai.

Testing of the Level 4 truck platform is scheduled to begin in the state of Arizona by the end of 2017.

TuSimple will start truck fleet testing in 2018, starting with two routes; one being a 120-mile highway stretch between Tucson and Phoenix in Arizona and another segment in Shanghai.

The company plans to introduce commercial autonomous trucking services the following year in 2019.