The Wisconsin Expeditious Legged Locomotion Laboratory at the University of Wisconsin-Madison (UW WELL Lab) studies the fundamental theory and methodologies in promoting mobility of legged robots that are robots moving in our environment using robotic legs: common examples include bipedal humanoid robots and quadrupedal animal-like robots. Our goal is to design advanced mechanical and algorithmic intelligence on legged robots with rigorous mathematical principles that are built from control theory, numerical optimization, and machine learning. The lab is open in January of 2023 when Dr. Xiaobin Xiong joined the department of Mechanical Engineering.