American automaker Ford and Chinese search giant Baidu are working hard on developing their own self-driving technology, but the two companies know it's sometimes smarter to buy expertise from elsewhere. Today, Ford and Baidu have announced a joint investment of $150 million in Velodyne — a Silicon Valley firm that makes LIDAR sensors essential for guiding autonomous cars. The investment will be used to make the company's sensors cheaper to produce, hopefully lowering the cost of self-driving tech.

LIDAR essentially works like radar, bouncing a signal off nearby objects to gauge their distance. However, while radar uses radio waves for this, LIDAR uses light waves — allowing for the creation of more detailed 3D maps of the sensor's surroundings. In a press statement, Velodyne said it's expecting an "exponential increase" in the demand for its technology, and that its aim is to make its sensors as cost effective as possible. "This investment will accelerate the cost reduction and scaling of Velodyne’s industry-leading LIDAR sensors, making them widely accessible and enabling mass deployment of fully autonomous vehicles," said the company's CEO and founder David Hall.

And they will certainly be put to use. Earlier this year, Baidu announced it was building a 100-person team in Silicon Valley to develop autonomous vehicles, going head-to-head with rival Google on the US company's home turf. Ford, too, is working on self-driving tech (along with every other major automaker), and this year plans to triple the size of its US test fleet.