His career at Sandia includes research in high-energy density physics, and material dynamics under extreme pressure and temperature. At Sandia Knudson led a team in developing a new, novel flyer plate capability using a magnetic loading technique. He applied this technique to several important scientific and programmatic problems, most notably the high-pressure response of hydrogen and its isotopes, the melting of beryllium and carbon on the Hugoniot, the high-pressure response of water at planetary relevant conditions, and defining the Hugoniot and release response of quartz for use as a high-precision standard in the multi-Mbar pressure regime. Using a shockramp technique, which greatly expands the region of phase space accessible through dynamic compression experiments, Knudson and his team experimentally observed a liquid-liquid, metal-to-insulator transition in hydrogen at low temperature and high density. He currently oversees the Z Fundamental Science Program.