Warehouse operators are investing heavily in technology as they manage labor challenges and high e-commerce volumes.

This year alone, Amazon opened a 3.8 million square-foot robotic fulfillment center, Maersk tested a new warehouse automation to pick and sort items and DHL Supply Chain announced plans to deploy an additional 5,000 Locus Robots in its global warehouse network.

The common theme? Warehouse operators are using automation to improve productivity, speed and efficiency.

Here are 10 stories over the past year that highlight warehouse technology investments.