Autonomous trucking is a hot commodity as investors once dazzled by self-driving cars are now pouring truckloads of money into automated logistics. The big picture: It's still not clear when robotaxis might be ready for large-scale deployment. Meanwhile, the explosion of e-commerce since the pandemic has created an increased demand for shipping. By the numbers: In the first half of 2021, investors pumped a record $5.6 billion into autonomous trucking companies such as TuSimple, Plus and Embark. Valuations for the top four companies in the truck sector soared 544% from Q2 2020 to Q2 2021, compared to only a 12% rise for the four largest robotaxi companies, according to PitchBook research.